Merge github.com:grpc/grpc into grpc_millis

552 files changed, 14612 insertions, 18318 deletions

diff --git a/src/core/ext/census/README.md b/src/core/ext/census/README.md
index fb615a2194..a9826fe889 100644
--- a/src/core/ext/census/README.md
+++ b/src/core/ext/census/README.md
@@ -1,32 +1,17 @@
 <!---
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
 -->
 
 # Census - a resource measurement and tracing system
diff --git a/src/core/ext/census/aggregation.h b/src/core/ext/census/aggregation.h
index 45f789c772..1ba7953ecc 100644
--- a/src/core/ext/census/aggregation.h
+++ b/src/core/ext/census/aggregation.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/census/base_resources.c b/src/core/ext/census/base_resources.c
index f9aa4bb994..2114bf04cd 100644
--- a/src/core/ext/census/base_resources.c
+++ b/src/core/ext/census/base_resources.c
@@ -1,32 +1,17 @@
 /*
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/census/base_resources.h b/src/core/ext/census/base_resources.h
index e5a7696db4..78a4d1fae5 100644
--- a/src/core/ext/census/base_resources.h
+++ b/src/core/ext/census/base_resources.h
@@ -1,32 +1,17 @@
 /*
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/census/census_init.c b/src/core/ext/census/census_init.c
index 690b09e789..d7f719ff8c 100644
--- a/src/core/ext/census/census_init.c
+++ b/src/core/ext/census/census_init.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/census/census_interface.h b/src/core/ext/census/census_interface.h
index 57e75f56ee..a42b68ad65 100644
--- a/src/core/ext/census/census_interface.h
+++ b/src/core/ext/census/census_interface.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/census/census_log.c b/src/core/ext/census/census_log.c
index 9a7331adc2..100047f12b 100644
--- a/src/core/ext/census/census_log.c
+++ b/src/core/ext/census/census_log.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/census/census_log.h b/src/core/ext/census/census_log.h
index 1b185a53b9..6b68b6bd37 100644
--- a/src/core/ext/census/census_log.h
+++ b/src/core/ext/census/census_log.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/census/census_rpc_stats.c b/src/core/ext/census/census_rpc_stats.c
index 09ee12d54b..0aca1f109e 100644
--- a/src/core/ext/census/census_rpc_stats.c
+++ b/src/core/ext/census/census_rpc_stats.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/census/census_rpc_stats.h b/src/core/ext/census/census_rpc_stats.h
index 7e4d8d1640..8004ade37d 100644
--- a/src/core/ext/census/census_rpc_stats.h
+++ b/src/core/ext/census/census_rpc_stats.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/census/census_tracing.c b/src/core/ext/census/census_tracing.c
index f893dc9864..199b260dd1 100644
--- a/src/core/ext/census/census_tracing.c
+++ b/src/core/ext/census/census_tracing.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/census/census_tracing.h b/src/core/ext/census/census_tracing.h
index 42a0d7403e..ccb767fcd0 100644
--- a/src/core/ext/census/census_tracing.h
+++ b/src/core/ext/census/census_tracing.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/census/context.c b/src/core/ext/census/context.c
index 4195cb1c9b..1019b287d7 100644
--- a/src/core/ext/census/context.c
+++ b/src/core/ext/census/context.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/census/gen/census.pb.c b/src/core/ext/census/gen/census.pb.c
index 647f0635b7..88efa73661 100644
--- a/src/core/ext/census/gen/census.pb.c
+++ b/src/core/ext/census/gen/census.pb.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 /* Automatically generated nanopb constant definitions */
diff --git a/src/core/ext/census/gen/census.pb.h b/src/core/ext/census/gen/census.pb.h
index c8546eac2e..5f28335664 100644
--- a/src/core/ext/census/gen/census.pb.h
+++ b/src/core/ext/census/gen/census.pb.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 /* Automatically generated nanopb header */
diff --git a/src/core/ext/census/gen/trace_context.pb.c b/src/core/ext/census/gen/trace_context.pb.c
index f4126d4d80..b5c3d52a71 100644
--- a/src/core/ext/census/gen/trace_context.pb.c
+++ b/src/core/ext/census/gen/trace_context.pb.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2017, Google Inc.
- * All rights reserved.
+ * Copyright 2017 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 /* Automatically generated nanopb constant definitions */
diff --git a/src/core/ext/census/gen/trace_context.pb.h b/src/core/ext/census/gen/trace_context.pb.h
index 6fafc04c81..181925dc9a 100644
--- a/src/core/ext/census/gen/trace_context.pb.h
+++ b/src/core/ext/census/gen/trace_context.pb.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2017, Google Inc.
- * All rights reserved.
+ * Copyright 2017 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 /* Automatically generated nanopb header */
diff --git a/src/core/ext/census/grpc_context.c b/src/core/ext/census/grpc_context.c
index 98285ab2d5..0bfba63a5e 100644
--- a/src/core/ext/census/grpc_context.c
+++ b/src/core/ext/census/grpc_context.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/census/grpc_filter.c b/src/core/ext/census/grpc_filter.c
index bcf59a4efe..13fe2e6b1c 100644
--- a/src/core/ext/census/grpc_filter.c
+++ b/src/core/ext/census/grpc_filter.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -156,7 +141,7 @@ static grpc_error *server_init_call_elem(grpc_exec_ctx *exec_ctx,
   memset(d, 0, sizeof(*d));
   d->start_ts = args->start_time;
   /* TODO(hongyu): call census_tracing_start_op here. */
-  grpc_closure_init(&d->finish_recv, server_on_done_recv, elem,
+  GRPC_CLOSURE_INIT(&d->finish_recv, server_on_done_recv, elem,
                     grpc_schedule_on_exec_ctx);
   return GRPC_ERROR_NONE;
 }
diff --git a/src/core/ext/census/grpc_filter.h b/src/core/ext/census/grpc_filter.h
index a39bd82224..baa7bb931a 100644
--- a/src/core/ext/census/grpc_filter.h
+++ b/src/core/ext/census/grpc_filter.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/census/grpc_plugin.c b/src/core/ext/census/grpc_plugin.c
index 7d0c9f14ae..c0efe5afb8 100644
--- a/src/core/ext/census/grpc_plugin.c
+++ b/src/core/ext/census/grpc_plugin.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/census/hash_table.c b/src/core/ext/census/hash_table.c
index ee6fdfc6e8..545b0857c7 100644
--- a/src/core/ext/census/hash_table.c
+++ b/src/core/ext/census/hash_table.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/census/hash_table.h b/src/core/ext/census/hash_table.h
index 30ea4264a2..75770641c5 100644
--- a/src/core/ext/census/hash_table.h
+++ b/src/core/ext/census/hash_table.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/census/initialize.c b/src/core/ext/census/initialize.c
index 55cbbe8e95..165a1221d4 100644
--- a/src/core/ext/census/initialize.c
+++ b/src/core/ext/census/initialize.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/census/intrusive_hash_map.c b/src/core/ext/census/intrusive_hash_map.c
new file mode 100644
index 0000000000..7930486963
--- /dev/null
+++ b/src/core/ext/census/intrusive_hash_map.c
@@ -0,0 +1,305 @@
+/*
+ *
+ * Copyright 2017 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+#include "src/core/ext/census/intrusive_hash_map.h"
+#include <string.h>
+
+extern bool hm_index_compare(const hm_index *A, const hm_index *B);
+
+/* Simple hashing function that takes lower 32 bits. */
+static __inline uint32_t chunked_vector_hasher(uint64_t key) {
+  return (uint32_t)key;
+}
+
+/* Vector chunks are 1MiB divided by pointer size. */
+static const size_t VECTOR_CHUNK_SIZE = (1 << 20) / sizeof(void *);
+
+/* Helper functions which return buckets from the chunked vector. */
+static __inline void **get_mutable_bucket(const chunked_vector *buckets,
+                                          uint32_t index) {
+  if (index < VECTOR_CHUNK_SIZE) {
+    return &buckets->first_[index];
+  }
+  size_t rest_index = (index - VECTOR_CHUNK_SIZE) / VECTOR_CHUNK_SIZE;
+  return &buckets->rest_[rest_index][index % VECTOR_CHUNK_SIZE];
+}
+
+static __inline void *get_bucket(const chunked_vector *buckets,
+                                 uint32_t index) {
+  if (index < VECTOR_CHUNK_SIZE) {
+    return buckets->first_[index];
+  }
+  size_t rest_index = (index - VECTOR_CHUNK_SIZE) / VECTOR_CHUNK_SIZE;
+  return buckets->rest_[rest_index][index % VECTOR_CHUNK_SIZE];
+}
+
+/* Helper function. */
+static __inline size_t RestSize(const chunked_vector *vec) {
+  return (vec->size_ <= VECTOR_CHUNK_SIZE)
+             ? 0
+             : (vec->size_ - VECTOR_CHUNK_SIZE - 1) / VECTOR_CHUNK_SIZE + 1;
+}
+
+/* Initialize chunked vector to size of 0. */
+static void chunked_vector_init(chunked_vector *vec) {
+  vec->size_ = 0;
+  vec->first_ = NULL;
+  vec->rest_ = NULL;
+}
+
+/* Clear chunked vector and free all memory that has been allocated then
+   initialize chunked vector. */
+static void chunked_vector_clear(chunked_vector *vec) {
+  if (vec->first_ != NULL) {
+    gpr_free(vec->first_);
+  }
+  if (vec->rest_ != NULL) {
+    size_t rest_size = RestSize(vec);
+    for (size_t i = 0; i < rest_size; ++i) {
+      if (vec->rest_[i] != NULL) {
+        gpr_free(vec->rest_[i]);
+      }
+    }
+    gpr_free(vec->rest_);
+  }
+  chunked_vector_init(vec);
+}
+
+/* Clear chunked vector and then resize it to n entries. Allow the first 1MB to
+   be read w/o an extra cache miss. The rest of the elements are stored in an
+   array of arrays to avoid large mallocs. */
+static void chunked_vector_reset(chunked_vector *vec, size_t n) {
+  chunked_vector_clear(vec);
+  vec->size_ = n;
+  if (n <= VECTOR_CHUNK_SIZE) {
+    vec->first_ = (void **)gpr_malloc(sizeof(void *) * n);
+    memset(vec->first_, 0, sizeof(void *) * n);
+  } else {
+    vec->first_ = (void **)gpr_malloc(sizeof(void *) * VECTOR_CHUNK_SIZE);
+    memset(vec->first_, 0, sizeof(void *) * VECTOR_CHUNK_SIZE);
+    size_t rest_size = RestSize(vec);
+    vec->rest_ = (void ***)gpr_malloc(sizeof(void **) * rest_size);
+    memset(vec->rest_, 0, sizeof(void **) * rest_size);
+    int i = 0;
+    n -= VECTOR_CHUNK_SIZE;
+    while (n > 0) {
+      size_t this_size = GPR_MIN(n, VECTOR_CHUNK_SIZE);
+      vec->rest_[i] = (void **)gpr_malloc(sizeof(void *) * this_size);
+      memset(vec->rest_[i], 0, sizeof(void *) * this_size);
+      n -= this_size;
+      ++i;
+    }
+  }
+}
+
+void intrusive_hash_map_init(intrusive_hash_map *hash_map,
+                             uint32_t initial_log2_table_size) {
+  hash_map->log2_num_buckets = initial_log2_table_size;
+  hash_map->num_items = 0;
+  uint32_t num_buckets = (uint32_t)1 << hash_map->log2_num_buckets;
+  hash_map->extend_threshold = num_buckets >> 1;
+  chunked_vector_init(&hash_map->buckets);
+  chunked_vector_reset(&hash_map->buckets, num_buckets);
+  hash_map->hash_mask = num_buckets - 1;
+}
+
+bool intrusive_hash_map_empty(const intrusive_hash_map *hash_map) {
+  return hash_map->num_items == 0;
+}
+
+size_t intrusive_hash_map_size(const intrusive_hash_map *hash_map) {
+  return hash_map->num_items;
+}
+
+void intrusive_hash_map_end(const intrusive_hash_map *hash_map, hm_index *idx) {
+  idx->bucket_index = (uint32_t)hash_map->buckets.size_;
+  GPR_ASSERT(idx->bucket_index <= UINT32_MAX);
+  idx->item = NULL;
+}
+
+void intrusive_hash_map_next(const intrusive_hash_map *hash_map,
+                             hm_index *idx) {
+  idx->item = idx->item->hash_link;
+  while (idx->item == NULL) {
+    idx->bucket_index++;
+    if (idx->bucket_index >= hash_map->buckets.size_) {
+      /* Reached end of table. */
+      idx->item = NULL;
+      return;
+    }
+    idx->item = (hm_item *)get_bucket(&hash_map->buckets, idx->bucket_index);
+  }
+}
+
+void intrusive_hash_map_begin(const intrusive_hash_map *hash_map,
+                              hm_index *idx) {
+  for (uint32_t i = 0; i < hash_map->buckets.size_; ++i) {
+    if (get_bucket(&hash_map->buckets, i) != NULL) {
+      idx->bucket_index = i;
+      idx->item = (hm_item *)get_bucket(&hash_map->buckets, i);
+      return;
+    }
+  }
+  intrusive_hash_map_end(hash_map, idx);
+}
+
+hm_item *intrusive_hash_map_find(const intrusive_hash_map *hash_map,
+                                 uint64_t key) {
+  uint32_t index = chunked_vector_hasher(key) & hash_map->hash_mask;
+
+  hm_item *p = (hm_item *)get_bucket(&hash_map->buckets, index);
+  while (p != NULL) {
+    if (key == p->key) {
+      return p;
+    }
+    p = p->hash_link;
+  }
+  return NULL;
+}
+
+hm_item *intrusive_hash_map_erase(intrusive_hash_map *hash_map, uint64_t key) {
+  uint32_t index = chunked_vector_hasher(key) & hash_map->hash_mask;
+
+  hm_item **slot = (hm_item **)get_mutable_bucket(&hash_map->buckets, index);
+  hm_item *p = *slot;
+  if (p == NULL) {
+    return NULL;
+  }
+
+  if (key == p->key) {
+    *slot = p->hash_link;
+    p->hash_link = NULL;
+    hash_map->num_items--;
+    return p;
+  }
+
+  hm_item *prev = p;
+  p = p->hash_link;
+
+  while (p) {
+    if (key == p->key) {
+      prev->hash_link = p->hash_link;
+      p->hash_link = NULL;
+      hash_map->num_items--;
+      return p;
+    }
+    prev = p;
+    p = p->hash_link;
+  }
+  return NULL;
+}
+
+/* Insert an hm_item* into the underlying chunked vector. hash_mask is
+ * array_size-1. Returns true if it is a new hm_item and false if the hm_item
+ * already existed.
+ */
+static __inline bool intrusive_hash_map_internal_insert(chunked_vector *buckets,
+                                                        uint32_t hash_mask,
+                                                        hm_item *item) {
+  const uint64_t key = item->key;
+  uint32_t index = chunked_vector_hasher(key) & hash_mask;
+  hm_item **slot = (hm_item **)get_mutable_bucket(buckets, index);
+  hm_item *p = *slot;
+  item->hash_link = p;
+
+  /* Check to see if key already exists. */
+  while (p) {
+    if (p->key == key) {
+      return false;
+    }
+    p = p->hash_link;
+  }
+
+  /* Otherwise add new entry. */
+  *slot = item;
+  return true;
+}
+
+/* Extend the allocated number of elements in the hash map by a factor of 2. */
+void intrusive_hash_map_extend(intrusive_hash_map *hash_map) {
+  uint32_t new_log2_num_buckets = 1 + hash_map->log2_num_buckets;
+  uint32_t new_num_buckets = (uint32_t)1 << new_log2_num_buckets;
+  GPR_ASSERT(new_num_buckets <= UINT32_MAX && new_num_buckets > 0);
+  chunked_vector new_buckets;
+  chunked_vector_init(&new_buckets);
+  chunked_vector_reset(&new_buckets, new_num_buckets);
+  uint32_t new_hash_mask = new_num_buckets - 1;
+
+  hm_index cur_idx;
+  hm_index end_idx;
+  intrusive_hash_map_end(hash_map, &end_idx);
+  intrusive_hash_map_begin(hash_map, &cur_idx);
+  while (!hm_index_compare(&cur_idx, &end_idx)) {
+    hm_item *new_item = cur_idx.item;
+    intrusive_hash_map_next(hash_map, &cur_idx);
+    intrusive_hash_map_internal_insert(&new_buckets, new_hash_mask, new_item);
+  }
+
+  /* Set values for new chunked_vector. extend_threshold is set to half of
+   * new_num_buckets. */
+  hash_map->log2_num_buckets = new_log2_num_buckets;
+  chunked_vector_clear(&hash_map->buckets);
+  hash_map->buckets = new_buckets;
+  hash_map->hash_mask = new_hash_mask;
+  hash_map->extend_threshold = new_num_buckets >> 1;
+}
+
+/* Insert a hm_item. The hm_item must remain live until it is removed from the
+   table. This object does not take the ownership of hm_item. The caller must
+   remove this hm_item from the table and delete it before this table is
+   deleted. If hm_item exists already num_items is not changed. */
+bool intrusive_hash_map_insert(intrusive_hash_map *hash_map, hm_item *item) {
+  if (hash_map->num_items >= hash_map->extend_threshold) {
+    intrusive_hash_map_extend(hash_map);
+  }
+  if (intrusive_hash_map_internal_insert(&hash_map->buckets,
+                                         hash_map->hash_mask, item)) {
+    hash_map->num_items++;
+    return true;
+  }
+  return false;
+}
+
+void intrusive_hash_map_clear(intrusive_hash_map *hash_map,
+                              void (*free_object)(void *)) {
+  hm_index cur;
+  hm_index end;
+  intrusive_hash_map_end(hash_map, &end);
+  intrusive_hash_map_begin(hash_map, &cur);
+
+  while (!hm_index_compare(&cur, &end)) {
+    hm_index next = cur;
+    intrusive_hash_map_next(hash_map, &next);
+    if (cur.item != NULL) {
+      hm_item *item = intrusive_hash_map_erase(hash_map, cur.item->key);
+      (*free_object)((void *)item);
+      gpr_free(item);
+    }
+    cur = next;
+  }
+}
+
+void intrusive_hash_map_free(intrusive_hash_map *hash_map,
+                             void (*free_object)(void *)) {
+  intrusive_hash_map_clear(hash_map, (*free_object));
+  hash_map->num_items = 0;
+  hash_map->extend_threshold = 0;
+  hash_map->log2_num_buckets = 0;
+  hash_map->hash_mask = 0;
+  chunked_vector_clear(&hash_map->buckets);
+}
diff --git a/src/core/ext/census/intrusive_hash_map.h b/src/core/ext/census/intrusive_hash_map.h
new file mode 100644
index 0000000000..f50de4fab4
--- /dev/null
+++ b/src/core/ext/census/intrusive_hash_map.h
@@ -0,0 +1,152 @@
+/*
+ *
+ * Copyright 2017 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+#ifndef GRPC_CORE_EXT_CENSUS_INTRUSIVE_HASH_MAP_H
+#define GRPC_CORE_EXT_CENSUS_INTRUSIVE_HASH_MAP_H
+
+#include "src/core/ext/census/intrusive_hash_map_internal.h"
+
+/* intrusive_hash_map is a fast chained hash table. This hash map is faster than
+ * a dense hash map when the application calls insert and erase more often than
+ * find. When the workload is dominated by find() a dense hash map may be
+ * faster.
+ *
+ * intrusive_hash_map uses an intrusive header placed within a user defined
+ * struct. The header field IHM_key MUST be set to a valid value before
+ * insertion into the hash map or undefined behavior may occur. The header field
+ * IHM_hash_link MUST to be set to NULL initially.
+ *
+ * EXAMPLE USAGE:
+ *
+ *  typedef struct string_item {
+ *    INTRUSIVE_HASH_MAP_HEADER;
+ *    // User data.
+ *    char *str_buf;
+ *    uint16_t len;
+ *  } string_item;
+ *
+ *  static string_item *make_string_item(uint64_t key, const char *buf,
+ *                                       uint16_t len) {
+ *    string_item *item = (string_item *)gpr_malloc(sizeof(string_item));
+ *    item->IHM_key = key;
+ *    item->IHM_hash_link = NULL;
+ *    item->len = len;
+ *    item->str_buf = (char *)malloc(len);
+ *    memcpy(item->str_buf, buf, len);
+ *    return item;
+ *  }
+ *
+ *  intrusive_hash_map hash_map;
+ *  intrusive_hash_map_init(&hash_map, 4);
+ *  string_item *new_item1 = make_string_item(10, "test1", 5);
+ *  bool ok = intrusive_hash_map_insert(&hash_map, (hm_item *)new_item1);
+ *
+ *  string_item *item1 =
+ *    (string_item *)intrusive_hash_map_find(&hash_map, 10);
+ */
+
+/* Hash map item. Stores key and a pointer to the actual object. A user defined
+ * version of this can be passed in provided the first 2 entries (key and
+ * hash_link) are the same. These entries must be first in the user defined
+ * struct. Pointer to struct will need to be cast as (hm_item *) when passed to
+ * hash map. This allows it to be intrusive. */
+typedef struct hm_item {
+  uint64_t key;
+  struct hm_item *hash_link;
+  /* Optional user defined data after this. */
+} hm_item;
+
+/* Macro provided for ease of use.  This must be first in the user defined
+ * struct (i.e. uint64_t key and hm_item * must be the first two elements in
+ * that order). */
+#define INTRUSIVE_HASH_MAP_HEADER \
+  uint64_t IHM_key;               \
+  struct hm_item *IHM_hash_link
+
+/* Index struct which acts as a pseudo-iterator within the hash map. */
+typedef struct hm_index {
+  uint32_t bucket_index;  // hash map bucket index.
+  hm_item *item;          // Pointer to hm_item within the hash map.
+} hm_index;
+
+/* Returns true if two hm_indices point to the same object within the hash map
+ * and false otherwise. */
+__inline bool hm_index_compare(const hm_index *A, const hm_index *B) {
+  return (A->item == B->item && A->bucket_index == B->bucket_index);
+}
+
+/*
+ * Helper functions for iterating over the hash map.
+ */
+
+/* On return idx will contain an invalid index which is always equal to
+ * hash_map->buckets.size_ */
+void intrusive_hash_map_end(const intrusive_hash_map *hash_map, hm_index *idx);
+
+/* Iterates index to the next valid entry in the hash map and stores the
+ * index within idx. If end of table is reached, idx will contain the same
+ * values as if intrusive_hash_map_end() was called. */
+void intrusive_hash_map_next(const intrusive_hash_map *hash_map, hm_index *idx);
+
+/* On return, idx will contain the index of the first non-null entry in the hash
+ * map. If the hash map is empty, idx will contain the same values as if
+ * intrusive_hash_map_end() was called. */
+void intrusive_hash_map_begin(const intrusive_hash_map *hash_map,
+                              hm_index *idx);
+
+/* Initialize intrusive hash map data structure. This must be called before
+ * the hash map can be used. The initial size of an intrusive hash map will be
+ * 2^initial_log2_map_size (valid range is [0, 31]). */
+void intrusive_hash_map_init(intrusive_hash_map *hash_map,
+                             uint32_t initial_log2_map_size);
+
+/* Returns true if the hash map is empty and false otherwise. */
+bool intrusive_hash_map_empty(const intrusive_hash_map *hash_map);
+
+/* Returns the number of elements currently in the hash map. */
+size_t intrusive_hash_map_size(const intrusive_hash_map *hash_map);
+
+/* Find a hm_item within the hash map by key. Returns NULL if item was not
+ * found. */
+hm_item *intrusive_hash_map_find(const intrusive_hash_map *hash_map,
+                                 uint64_t key);
+
+/* Erase the hm_item that corresponds with key. If the hm_item is found, return
+ * the pointer to the hm_item. Else returns NULL. */
+hm_item *intrusive_hash_map_erase(intrusive_hash_map *hash_map, uint64_t key);
+
+/* Attempts to insert a new hm_item into the hash map.  If an element with the
+ * same key already exists, it will not insert the new item and return false.
+ * Otherwise, it will insert the new item and return true. */
+bool intrusive_hash_map_insert(intrusive_hash_map *hash_map, hm_item *item);
+
+/* Clears entire contents of the hash map, but leaves internal data structure
+ * untouched. Second argument takes a function pointer to a function that will
+ * free the object designated by the user and pointed to by hash_map->value. */
+void intrusive_hash_map_clear(intrusive_hash_map *hash_map,
+                              void (*free_object)(void *));
+
+/* Erase all contents of hash map and free the memory. Hash map is invalid
+ * after calling this function and cannot be used until it has been
+ * reinitialized (intrusive_hash_map_init()). This function takes a function
+ * pointer to a function that will free the object designated by the user and
+ * pointed to by hash_map->value. */
+void intrusive_hash_map_free(intrusive_hash_map *hash_map,
+                             void (*free_object)(void *));
+
+#endif /* GRPC_CORE_EXT_CENSUS_INTRUSIVE_HASH_MAP_H */
diff --git a/src/core/ext/census/intrusive_hash_map_internal.h b/src/core/ext/census/intrusive_hash_map_internal.h
new file mode 100644
index 0000000000..e9c81fc85c
--- /dev/null
+++ b/src/core/ext/census/intrusive_hash_map_internal.h
@@ -0,0 +1,48 @@
+/*
+ *
+ * Copyright 2017 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+#ifndef GRPC_CORE_EXT_CENSUS_INTRUSIVE_HASH_MAP_INTERNAL_H
+#define GRPC_CORE_EXT_CENSUS_INTRUSIVE_HASH_MAP_INTERNAL_H
+
+#include <grpc/support/alloc.h>
+#include <grpc/support/log.h>
+#include <grpc/support/useful.h>
+#include <stdbool.h>
+
+/* The chunked vector is a data structure that allocates buckets for use in the
+ * hash map. ChunkedVector is logically equivalent to T*[N] (cast void* as
+ * T*). It's internally implemented as an array of 1MB arrays to avoid
+ * allocating large consecutive memory chunks. This is an internal data
+ * structure that should never be accessed directly. */
+typedef struct chunked_vector {
+  size_t size_;
+  void **first_;
+  void ***rest_;
+} chunked_vector;
+
+/* Core intrusive hash map data structure. All internal elements are managed by
+ * functions and should not be altered manually. */
+typedef struct intrusive_hash_map {
+  uint32_t num_items;
+  uint32_t extend_threshold;
+  uint32_t log2_num_buckets;
+  uint32_t hash_mask;
+  chunked_vector buckets;
+} intrusive_hash_map;
+
+#endif /* GRPC_CORE_EXT_CENSUS_INTRUSIVE_HASH_MAP_INTERNAL_H */
diff --git a/src/core/ext/census/mlog.c b/src/core/ext/census/mlog.c
index 698b7096ab..937ceb101b 100644
--- a/src/core/ext/census/mlog.c
+++ b/src/core/ext/census/mlog.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/census/mlog.h b/src/core/ext/census/mlog.h
index 18805ad994..6f3125944f 100644
--- a/src/core/ext/census/mlog.h
+++ b/src/core/ext/census/mlog.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/census/operation.c b/src/core/ext/census/operation.c
index 5c58704372..be88ac74e6 100644
--- a/src/core/ext/census/operation.c
+++ b/src/core/ext/census/operation.c
@@ -1,32 +1,17 @@
 /*
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/census/placeholders.c b/src/core/ext/census/placeholders.c
index 9f99c5bdcf..bed9837ee3 100644
--- a/src/core/ext/census/placeholders.c
+++ b/src/core/ext/census/placeholders.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/census/resource.c b/src/core/ext/census/resource.c
index 26ea1a8672..1a676f0e1e 100644
--- a/src/core/ext/census/resource.c
+++ b/src/core/ext/census/resource.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/census/resource.h b/src/core/ext/census/resource.h
index 591bff07da..b8bda2c72e 100644
--- a/src/core/ext/census/resource.h
+++ b/src/core/ext/census/resource.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/census/rpc_metric_id.h b/src/core/ext/census/rpc_metric_id.h
index 888ec500a7..ea493d7288 100644
--- a/src/core/ext/census/rpc_metric_id.h
+++ b/src/core/ext/census/rpc_metric_id.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/census/trace_context.c b/src/core/ext/census/trace_context.c
index 47d0de19da..af92ae6d9e 100644
--- a/src/core/ext/census/trace_context.c
+++ b/src/core/ext/census/trace_context.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/census/trace_context.h b/src/core/ext/census/trace_context.h
index f391a1b7c1..a7233e6a2b 100644
--- a/src/core/ext/census/trace_context.h
+++ b/src/core/ext/census/trace_context.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/census/trace_label.h b/src/core/ext/census/trace_label.h
index 701f6f5a63..97ce399eb5 100644
--- a/src/core/ext/census/trace_label.h
+++ b/src/core/ext/census/trace_label.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/census/trace_propagation.h b/src/core/ext/census/trace_propagation.h
index 0c27bfa111..eecfcb7d01 100644
--- a/src/core/ext/census/trace_propagation.h
+++ b/src/core/ext/census/trace_propagation.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/census/trace_status.h b/src/core/ext/census/trace_status.h
index 0734ec6d3d..dd83d3f729 100644
--- a/src/core/ext/census/trace_status.h
+++ b/src/core/ext/census/trace_status.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/census/trace_string.h b/src/core/ext/census/trace_string.h
index cd63cfb92f..e4da3f590d 100644
--- a/src/core/ext/census/trace_string.h
+++ b/src/core/ext/census/trace_string.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/census/tracing.c b/src/core/ext/census/tracing.c
index 8b74628f4f..543a73c5ad 100644
--- a/src/core/ext/census/tracing.c
+++ b/src/core/ext/census/tracing.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/census/tracing.h b/src/core/ext/census/tracing.h
index 3a7c6f45e4..038c9e2790 100644
--- a/src/core/ext/census/tracing.h
+++ b/src/core/ext/census/tracing.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/census/window_stats.c b/src/core/ext/census/window_stats.c
index 5f7bd9952e..0058e4bf9c 100644
--- a/src/core/ext/census/window_stats.c
+++ b/src/core/ext/census/window_stats.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/census/window_stats.h b/src/core/ext/census/window_stats.h
index 25658c9ce0..ebe3732008 100644
--- a/src/core/ext/census/window_stats.h
+++ b/src/core/ext/census/window_stats.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/filters/client_channel/OWNERS b/src/core/ext/filters/client_channel/OWNERS
new file mode 100644
index 0000000000..773bc73179
--- /dev/null
+++ b/src/core/ext/filters/client_channel/OWNERS
@@ -0,0 +1,4 @@
+set noparent
+@markdroth
+@dgquintas
+@ctiller
diff --git a/src/core/ext/filters/client_channel/channel_connectivity.c b/src/core/ext/filters/client_channel/channel_connectivity.c
index 4ccbd5c13d..c3dca14305 100644
--- a/src/core/ext/filters/client_channel/channel_connectivity.c
+++ b/src/core/ext/filters/client_channel/channel_connectivity.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -67,9 +52,8 @@ grpc_connectivity_state grpc_channel_check_connectivity_state(
 
 typedef enum {
   WAITING,
-  CALLING_BACK,
+  READY_TO_CALL_BACK,
   CALLING_BACK_AND_FINISHED,
-  CALLED_BACK
 } callback_phase;
 
 typedef struct {
@@ -77,11 +61,13 @@ typedef struct {
   callback_phase phase;
   grpc_closure on_complete;
   grpc_closure on_timeout;
+  grpc_closure watcher_timer_init;
   grpc_timer alarm;
   grpc_connectivity_state state;
   grpc_completion_queue *cq;
   grpc_cq_completion completion_storage;
   grpc_channel *channel;
+  grpc_error *error;
   void *tag;
 } state_watcher;
 
@@ -105,11 +91,8 @@ static void finished_completion(grpc_exec_ctx *exec_ctx, void *pw,
   gpr_mu_lock(&w->mu);
   switch (w->phase) {
     case WAITING:
-    case CALLED_BACK:
+    case READY_TO_CALL_BACK:
       GPR_UNREACHABLE_CODE(return );
-    case CALLING_BACK:
-      w->phase = CALLED_BACK;
-      break;
     case CALLING_BACK_AND_FINISHED:
       delete = 1;
       break;
@@ -123,10 +106,15 @@ static void finished_completion(grpc_exec_ctx *exec_ctx, void *pw,
 
 static void partly_done(grpc_exec_ctx *exec_ctx, state_watcher *w,
                         bool due_to_completion, grpc_error *error) {
-  int delete = 0;
-
   if (due_to_completion) {
     grpc_timer_cancel(exec_ctx, &w->alarm);
+  } else {
+    grpc_channel_element *client_channel_elem = grpc_channel_stack_last_element(
+        grpc_channel_get_channel_stack(w->channel));
+    grpc_client_channel_watch_connectivity_state(
+        exec_ctx, client_channel_elem,
+        grpc_polling_entity_create_from_pollset(grpc_cq_pollset(w->cq)), NULL,
+        &w->on_complete, NULL);
   }
 
   gpr_mu_lock(&w->mu);
@@ -147,25 +135,27 @@ static void partly_done(grpc_exec_ctx *exec_ctx, state_watcher *w,
   }
   switch (w->phase) {
     case WAITING:
-      w->phase = CALLING_BACK;
-      grpc_cq_end_op(exec_ctx, w->cq, w->tag, GRPC_ERROR_REF(error),
-                     finished_completion, w, &w->completion_storage);
+      GRPC_ERROR_REF(error);
+      w->error = error;
+      w->phase = READY_TO_CALL_BACK;
       break;
-    case CALLING_BACK:
+    case READY_TO_CALL_BACK:
+      if (error != GRPC_ERROR_NONE) {
+        GPR_ASSERT(!due_to_completion);
+        GRPC_ERROR_UNREF(w->error);
+        GRPC_ERROR_REF(error);
+        w->error = error;
+      }
       w->phase = CALLING_BACK_AND_FINISHED;
+      grpc_cq_end_op(exec_ctx, w->cq, w->tag, w->error, finished_completion, w,
+                     &w->completion_storage);
       break;
     case CALLING_BACK_AND_FINISHED:
       GPR_UNREACHABLE_CODE(return );
-    case CALLED_BACK:
-      delete = 1;
       break;
   }
   gpr_mu_unlock(&w->mu);
 
-  if (delete) {
-    delete_state_watcher(exec_ctx, w);
-  }
-
   GRPC_ERROR_UNREF(error);
 }
 
@@ -179,6 +169,28 @@ static void timeout_complete(grpc_exec_ctx *exec_ctx, void *pw,
   partly_done(exec_ctx, pw, false, GRPC_ERROR_REF(error));
 }
 
+int grpc_channel_num_external_connectivity_watchers(grpc_channel *channel) {
+  grpc_channel_element *client_channel_elem =
+      grpc_channel_stack_last_element(grpc_channel_get_channel_stack(channel));
+  return grpc_client_channel_num_external_connectivity_watchers(
+      client_channel_elem);
+}
+
+typedef struct watcher_timer_init_arg {
+  state_watcher *w;
+  gpr_timespec deadline;
+} watcher_timer_init_arg;
+
+static void watcher_timer_init(grpc_exec_ctx *exec_ctx, void *arg,
+                               grpc_error *error_ignored) {
+  watcher_timer_init_arg *wa = (watcher_timer_init_arg *)arg;
+
+  grpc_timer_init(exec_ctx, &wa->w->alarm,
+                  gpr_convert_clock_type(wa->deadline, GPR_CLOCK_MONOTONIC),
+                  &wa->w->on_timeout, gpr_now(GPR_CLOCK_MONOTONIC));
+  gpr_free(wa);
+}
+
 void grpc_channel_watch_connectivity_state(
     grpc_channel *channel, grpc_connectivity_state last_observed_state,
     gpr_timespec deadline, grpc_completion_queue *cq, void *tag) {
@@ -199,24 +211,29 @@ void grpc_channel_watch_connectivity_state(
   grpc_cq_begin_op(cq, tag);
 
   gpr_mu_init(&w->mu);
-  grpc_closure_init(&w->on_complete, watch_complete, w,
+  GRPC_CLOSURE_INIT(&w->on_complete, watch_complete, w,
                     grpc_schedule_on_exec_ctx);
-  grpc_closure_init(&w->on_timeout, timeout_complete, w,
+  GRPC_CLOSURE_INIT(&w->on_timeout, timeout_complete, w,
                     grpc_schedule_on_exec_ctx);
   w->phase = WAITING;
   w->state = last_observed_state;
   w->cq = cq;
   w->tag = tag;
   w->channel = channel;
+  w->error = NULL;
 
-  grpc_timer_init(&exec_ctx, &w->alarm,
-                  grpc_timespec_to_millis(&exec_ctx, deadline), &w->on_timeout);
+  watcher_timer_init_arg *wa = gpr_malloc(sizeof(watcher_timer_init_arg));
+  wa->w = w;
+  wa->deadline = deadline;
+  GRPC_CLOSURE_INIT(&w->watcher_timer_init, watcher_timer_init, wa,
+                    grpc_schedule_on_exec_ctx);
 
   if (client_channel_elem->filter == &grpc_client_channel_filter) {
     GRPC_CHANNEL_INTERNAL_REF(channel, "watch_channel_connectivity");
-    grpc_client_channel_watch_connectivity_state(&exec_ctx, client_channel_elem,
-                                                 grpc_cq_pollset(cq), &w->state,
-                                                 &w->on_complete);
+    grpc_client_channel_watch_connectivity_state(
+        &exec_ctx, client_channel_elem,
+        grpc_polling_entity_create_from_pollset(grpc_cq_pollset(cq)), &w->state,
+        &w->on_complete, &w->watcher_timer_init);
   } else {
     abort();
   }
diff --git a/src/core/ext/filters/client_channel/client_channel.c b/src/core/ext/filters/client_channel/client_channel.c
index 24843d52e9..58e31d7b45 100644
--- a/src/core/ext/filters/client_channel/client_channel.c
+++ b/src/core/ext/filters/client_channel/client_channel.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -67,6 +52,9 @@
 
 /* Client channel implementation */
 
+grpc_tracer_flag grpc_client_channel_trace =
+    GRPC_TRACER_INITIALIZER(false, "client_channel");
+
 /*************************************************************************
  * METHOD-CONFIG TABLE
  */
@@ -167,6 +155,8 @@ static void *method_parameters_create_from_json(const grpc_json *json) {
   return value;
 }
 
+struct external_connectivity_watcher;
+
 /*************************************************************************
  * CHANNEL-WIDE FUNCTIONS
  */
@@ -191,8 +181,8 @@ typedef struct client_channel_channel_data {
   grpc_slice_hash_table *method_params_table;
   /** incoming resolver result - set by resolver.next() */
   grpc_channel_args *resolver_result;
-  /** a list of closures that are all waiting for config to come in */
-  grpc_closure_list waiting_for_config_closures;
+  /** a list of closures that are all waiting for resolver result to come in */
+  grpc_closure_list waiting_for_resolver_result_closures;
   /** resolver callback */
   grpc_closure on_resolver_result_changed;
   /** connectivity state being tracked */
@@ -204,6 +194,11 @@ typedef struct client_channel_channel_data {
   /** interested parties (owned) */
   grpc_pollset_set *interested_parties;
 
+  /* external_connectivity_watcher_list head is guarded by its own mutex, since
+   * counts need to be grabbed immediately without polling on a cq */
+  gpr_mu external_connectivity_watcher_list_mu;
+  struct external_connectivity_watcher *external_connectivity_watcher_list_head;
+
   /* the following properties are guarded by a mutex since API's require them
      to be instantaneously available */
   gpr_mu info_mu;
@@ -249,6 +244,10 @@ static void set_channel_connectivity_state_locked(grpc_exec_ctx *exec_ctx,
                                          GRPC_ERROR_REF(error));
     }
   }
+  if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+    gpr_log(GPR_DEBUG, "chand=%p: setting connectivity state to %s", chand,
+            grpc_connectivity_state_name(state));
+  }
   grpc_connectivity_state_set(exec_ctx, &chand->state_tracker, state, error,
                               reason);
 }
@@ -259,6 +258,10 @@ static void on_lb_policy_state_changed_locked(grpc_exec_ctx *exec_ctx,
   grpc_connectivity_state publish_state = w->state;
   /* check if the notification is for the latest policy */
   if (w->lb_policy == w->chand->lb_policy) {
+    if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+      gpr_log(GPR_DEBUG, "chand=%p: lb_policy=%p state changed to %s", w->chand,
+              w->lb_policy, grpc_connectivity_state_name(w->state));
+    }
     if (publish_state == GRPC_CHANNEL_SHUTDOWN && w->chand->resolver != NULL) {
       publish_state = GRPC_CHANNEL_TRANSIENT_FAILURE;
       grpc_resolver_channel_saw_error_locked(exec_ctx, w->chand->resolver);
@@ -271,7 +274,6 @@ static void on_lb_policy_state_changed_locked(grpc_exec_ctx *exec_ctx,
       watch_lb_policy_locked(exec_ctx, w->chand, w->lb_policy, w->state);
     }
   }
-
   GRPC_CHANNEL_STACK_UNREF(exec_ctx, w->chand->owning_stack, "watch_lb_policy");
   gpr_free(w);
 }
@@ -281,16 +283,27 @@ static void watch_lb_policy_locked(grpc_exec_ctx *exec_ctx, channel_data *chand,
                                    grpc_connectivity_state current_state) {
   lb_policy_connectivity_watcher *w = gpr_malloc(sizeof(*w));
   GRPC_CHANNEL_STACK_REF(chand->owning_stack, "watch_lb_policy");
-
   w->chand = chand;
-  grpc_closure_init(&w->on_changed, on_lb_policy_state_changed_locked, w,
-                    grpc_combiner_scheduler(chand->combiner, false));
+  GRPC_CLOSURE_INIT(&w->on_changed, on_lb_policy_state_changed_locked, w,
+                    grpc_combiner_scheduler(chand->combiner));
   w->state = current_state;
   w->lb_policy = lb_policy;
   grpc_lb_policy_notify_on_state_change_locked(exec_ctx, lb_policy, &w->state,
                                                &w->on_changed);
 }
 
+static void start_resolving_locked(grpc_exec_ctx *exec_ctx,
+                                   channel_data *chand) {
+  if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+    gpr_log(GPR_DEBUG, "chand=%p: starting name resolution", chand);
+  }
+  GPR_ASSERT(!chand->started_resolving);
+  chand->started_resolving = true;
+  GRPC_CHANNEL_STACK_REF(chand->owning_stack, "resolver");
+  grpc_resolver_next_locked(exec_ctx, chand->resolver, &chand->resolver_result,
+                            &chand->on_resolver_result_changed);
+}
+
 typedef struct {
   char *server_name;
   grpc_server_retry_throttle_data *retry_throttle_data;
@@ -350,48 +363,21 @@ static void parse_retry_throttle_params(const grpc_json *field, void *arg) {
   }
 }
 
-// Wrap a closure associated with \a lb_policy. The associated callback (\a
-// wrapped_on_pick_closure_cb) is responsible for unref'ing \a lb_policy after
-// scheduling \a wrapped_closure.
-typedef struct wrapped_on_pick_closure_arg {
-  /* the closure instance using this struct as argument */
-  grpc_closure wrapper_closure;
-
-  /* the original closure. Usually a on_complete/notify cb for pick() and ping()
-   * calls against the internal RR instance, respectively. */
-  grpc_closure *wrapped_closure;
-
-  /* The policy instance related to the closure */
-  grpc_lb_policy *lb_policy;
-} wrapped_on_pick_closure_arg;
-
-// Invoke \a arg->wrapped_closure, unref \a arg->lb_policy and free \a arg.
-static void wrapped_on_pick_closure_cb(grpc_exec_ctx *exec_ctx, void *arg,
-                                       grpc_error *error) {
-  wrapped_on_pick_closure_arg *wc_arg = arg;
-  GPR_ASSERT(wc_arg != NULL);
-  GPR_ASSERT(wc_arg->wrapped_closure != NULL);
-  GPR_ASSERT(wc_arg->lb_policy != NULL);
-  grpc_closure_run(exec_ctx, wc_arg->wrapped_closure, GRPC_ERROR_REF(error));
-  GRPC_LB_POLICY_UNREF(exec_ctx, wc_arg->lb_policy, "pick_subchannel_wrapping");
-  gpr_free(wc_arg);
-}
-
 static void on_resolver_result_changed_locked(grpc_exec_ctx *exec_ctx,
                                               void *arg, grpc_error *error) {
   channel_data *chand = arg;
+  if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+    gpr_log(GPR_DEBUG, "chand=%p: got resolver result: error=%s", chand,
+            grpc_error_string(error));
+  }
+  // Extract the following fields from the resolver result, if non-NULL.
+  bool lb_policy_updated = false;
   char *lb_policy_name = NULL;
-  grpc_lb_policy *lb_policy = NULL;
-  grpc_lb_policy *old_lb_policy;
-  grpc_slice_hash_table *method_params_table = NULL;
-  grpc_connectivity_state state = GRPC_CHANNEL_TRANSIENT_FAILURE;
-  bool exit_idle = false;
-  grpc_error *state_error =
-      GRPC_ERROR_CREATE_FROM_STATIC_STRING("No load balancing policy");
+  bool lb_policy_name_changed = false;
+  grpc_lb_policy *new_lb_policy = NULL;
   char *service_config_json = NULL;
-  service_config_parsing_state parsing_state;
-  memset(&parsing_state, 0, sizeof(parsing_state));
-
+  grpc_server_retry_throttle_data *retry_throttle_data = NULL;
+  grpc_slice_hash_table *method_params_table = NULL;
   if (chand->resolver_result != NULL) {
     // Find LB policy name.
     const grpc_arg *channel_arg =
@@ -426,18 +412,29 @@ static void on_resolver_result_changed_locked(grpc_exec_ctx *exec_ctx,
     // Use pick_first if nothing was specified and we didn't select grpclb
     // above.
     if (lb_policy_name == NULL) lb_policy_name = "pick_first";
-    // Instantiate LB policy.
     grpc_lb_policy_args lb_policy_args;
     lb_policy_args.args = chand->resolver_result;
     lb_policy_args.client_channel_factory = chand->client_channel_factory;
     lb_policy_args.combiner = chand->combiner;
-    lb_policy =
-        grpc_lb_policy_create(exec_ctx, lb_policy_name, &lb_policy_args);
-    if (lb_policy != NULL) {
-      GRPC_LB_POLICY_REF(lb_policy, "config_change");
-      GRPC_ERROR_UNREF(state_error);
-      state = grpc_lb_policy_check_connectivity_locked(exec_ctx, lb_policy,
-                                                       &state_error);
+    // Check to see if we're already using the right LB policy.
+    // Note: It's safe to use chand->info_lb_policy_name here without
+    // taking a lock on chand->info_mu, because this function is the
+    // only thing that modifies its value, and it can only be invoked
+    // once at any given time.
+    lb_policy_name_changed =
+        chand->info_lb_policy_name == NULL ||
+        strcmp(chand->info_lb_policy_name, lb_policy_name) != 0;
+    if (chand->lb_policy != NULL && !lb_policy_name_changed) {
+      // Continue using the same LB policy.  Update with new addresses.
+      lb_policy_updated = true;
+      grpc_lb_policy_update_locked(exec_ctx, chand->lb_policy, &lb_policy_args);
+    } else {
+      // Instantiate new LB policy.
+      new_lb_policy =
+          grpc_lb_policy_create(exec_ctx, lb_policy_name, &lb_policy_args);
+      if (new_lb_policy == NULL) {
+        gpr_log(GPR_ERROR, "could not create LB policy \"%s\"", lb_policy_name);
+      }
     }
     // Find service config.
     channel_arg =
@@ -455,12 +452,14 @@ static void on_resolver_result_changed_locked(grpc_exec_ctx *exec_ctx,
         grpc_uri *uri =
             grpc_uri_parse(exec_ctx, channel_arg->value.string, true);
         GPR_ASSERT(uri->path[0] != '\0');
+        service_config_parsing_state parsing_state;
+        memset(&parsing_state, 0, sizeof(parsing_state));
         parsing_state.server_name =
             uri->path[0] == '/' ? uri->path + 1 : uri->path;
         grpc_service_config_parse_global_params(
             service_config, parse_retry_throttle_params, &parsing_state);
-        parsing_state.server_name = NULL;
         grpc_uri_destroy(uri);
+        retry_throttle_data = parsing_state.retry_throttle_data;
         method_params_table = grpc_service_config_create_method_config_table(
             exec_ctx, service_config, method_parameters_create_from_json,
             method_parameters_free);
@@ -474,88 +473,115 @@ static void on_resolver_result_changed_locked(grpc_exec_ctx *exec_ctx,
     grpc_channel_args_destroy(exec_ctx, chand->resolver_result);
     chand->resolver_result = NULL;
   }
-
-  if (lb_policy != NULL) {
-    grpc_pollset_set_add_pollset_set(exec_ctx, lb_policy->interested_parties,
-                                     chand->interested_parties);
-  }
-
+  if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+    gpr_log(GPR_DEBUG,
+            "chand=%p: resolver result: lb_policy_name=\"%s\"%s, "
+            "service_config=\"%s\"",
+            chand, lb_policy_name, lb_policy_name_changed ? " (changed)" : "",
+            service_config_json);
+  }
+  // Now swap out fields in chand.  Note that the new values may still
+  // be NULL if (e.g.) the resolver failed to return results or the
+  // results did not contain the necessary data.
+  //
+  // First, swap out the data used by cc_get_channel_info().
   gpr_mu_lock(&chand->info_mu);
   if (lb_policy_name != NULL) {
     gpr_free(chand->info_lb_policy_name);
     chand->info_lb_policy_name = lb_policy_name;
   }
-  old_lb_policy = chand->lb_policy;
-  chand->lb_policy = lb_policy;
   if (service_config_json != NULL) {
     gpr_free(chand->info_service_config_json);
     chand->info_service_config_json = service_config_json;
   }
   gpr_mu_unlock(&chand->info_mu);
-
+  // Swap out the retry throttle data.
   if (chand->retry_throttle_data != NULL) {
     grpc_server_retry_throttle_data_unref(chand->retry_throttle_data);
   }
-  chand->retry_throttle_data = parsing_state.retry_throttle_data;
+  chand->retry_throttle_data = retry_throttle_data;
+  // Swap out the method params table.
   if (chand->method_params_table != NULL) {
     grpc_slice_hash_table_unref(exec_ctx, chand->method_params_table);
   }
   chand->method_params_table = method_params_table;
-  if (lb_policy != NULL) {
-    grpc_closure_list_sched(exec_ctx, &chand->waiting_for_config_closures);
-  } else if (chand->resolver == NULL /* disconnected */) {
-    grpc_closure_list_fail_all(&chand->waiting_for_config_closures,
-                               GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
-                                   "Channel disconnected", &error, 1));
-    grpc_closure_list_sched(exec_ctx, &chand->waiting_for_config_closures);
-  }
-  if (lb_policy != NULL && chand->exit_idle_when_lb_policy_arrives) {
-    GRPC_LB_POLICY_REF(lb_policy, "exit_idle");
-    exit_idle = true;
-    chand->exit_idle_when_lb_policy_arrives = false;
+  // If we have a new LB policy or are shutting down (in which case
+  // new_lb_policy will be NULL), swap out the LB policy, unreffing the
+  // old one and removing its fds from chand->interested_parties.
+  // Note that we do NOT do this if either (a) we updated the existing
+  // LB policy above or (b) we failed to create the new LB policy (in
+  // which case we want to continue using the most recent one we had).
+  if (new_lb_policy != NULL || error != GRPC_ERROR_NONE ||
+      chand->resolver == NULL) {
+    if (chand->lb_policy != NULL) {
+      if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+        gpr_log(GPR_DEBUG, "chand=%p: unreffing lb_policy=%p", chand,
+                chand->lb_policy);
+      }
+      grpc_pollset_set_del_pollset_set(exec_ctx,
+                                       chand->lb_policy->interested_parties,
+                                       chand->interested_parties);
+      GRPC_LB_POLICY_UNREF(exec_ctx, chand->lb_policy, "channel");
+    }
+    chand->lb_policy = new_lb_policy;
   }
-
-  if (error == GRPC_ERROR_NONE && chand->resolver) {
-    set_channel_connectivity_state_locked(
-        exec_ctx, chand, state, GRPC_ERROR_REF(state_error), "new_lb+resolver");
-    if (lb_policy != NULL) {
-      watch_lb_policy_locked(exec_ctx, chand, lb_policy, state);
+  // Now that we've swapped out the relevant fields of chand, check for
+  // error or shutdown.
+  if (error != GRPC_ERROR_NONE || chand->resolver == NULL) {
+    if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+      gpr_log(GPR_DEBUG, "chand=%p: shutting down", chand);
     }
-    GRPC_CHANNEL_STACK_REF(chand->owning_stack, "resolver");
-    grpc_resolver_next_locked(exec_ctx, chand->resolver,
-                              &chand->resolver_result,
-                              &chand->on_resolver_result_changed);
-  } else {
     if (chand->resolver != NULL) {
+      if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+        gpr_log(GPR_DEBUG, "chand=%p: shutting down resolver", chand);
+      }
       grpc_resolver_shutdown_locked(exec_ctx, chand->resolver);
       GRPC_RESOLVER_UNREF(exec_ctx, chand->resolver, "channel");
       chand->resolver = NULL;
     }
-    grpc_error *refs[] = {error, state_error};
     set_channel_connectivity_state_locked(
         exec_ctx, chand, GRPC_CHANNEL_SHUTDOWN,
         GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
-            "Got config after disconnection", refs, GPR_ARRAY_SIZE(refs)),
+            "Got resolver result after disconnection", &error, 1),
         "resolver_gone");
+    GRPC_CHANNEL_STACK_UNREF(exec_ctx, chand->owning_stack, "resolver");
+    grpc_closure_list_fail_all(&chand->waiting_for_resolver_result_closures,
+                               GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
+                                   "Channel disconnected", &error, 1));
+    GRPC_CLOSURE_LIST_SCHED(exec_ctx,
+                            &chand->waiting_for_resolver_result_closures);
+  } else {  // Not shutting down.
+    grpc_connectivity_state state = GRPC_CHANNEL_TRANSIENT_FAILURE;
+    grpc_error *state_error =
+        GRPC_ERROR_CREATE_FROM_STATIC_STRING("No load balancing policy");
+    if (new_lb_policy != NULL) {
+      if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+        gpr_log(GPR_DEBUG, "chand=%p: initializing new LB policy", chand);
+      }
+      GRPC_ERROR_UNREF(state_error);
+      state = grpc_lb_policy_check_connectivity_locked(exec_ctx, new_lb_policy,
+                                                       &state_error);
+      grpc_pollset_set_add_pollset_set(exec_ctx,
+                                       new_lb_policy->interested_parties,
+                                       chand->interested_parties);
+      GRPC_CLOSURE_LIST_SCHED(exec_ctx,
+                              &chand->waiting_for_resolver_result_closures);
+      if (chand->exit_idle_when_lb_policy_arrives) {
+        grpc_lb_policy_exit_idle_locked(exec_ctx, new_lb_policy);
+        chand->exit_idle_when_lb_policy_arrives = false;
+      }
+      watch_lb_policy_locked(exec_ctx, chand, new_lb_policy, state);
+    }
+    if (!lb_policy_updated) {
+      set_channel_connectivity_state_locked(exec_ctx, chand, state,
+                                            GRPC_ERROR_REF(state_error),
+                                            "new_lb+resolver");
+    }
+    grpc_resolver_next_locked(exec_ctx, chand->resolver,
+                              &chand->resolver_result,
+                              &chand->on_resolver_result_changed);
+    GRPC_ERROR_UNREF(state_error);
   }
-
-  if (exit_idle) {
-    grpc_lb_policy_exit_idle_locked(exec_ctx, lb_policy);
-    GRPC_LB_POLICY_UNREF(exec_ctx, lb_policy, "exit_idle");
-  }
-
-  if (old_lb_policy != NULL) {
-    grpc_pollset_set_del_pollset_set(
-        exec_ctx, old_lb_policy->interested_parties, chand->interested_parties);
-    GRPC_LB_POLICY_UNREF(exec_ctx, old_lb_policy, "channel");
-  }
-
-  if (lb_policy != NULL) {
-    GRPC_LB_POLICY_UNREF(exec_ctx, lb_policy, "config_change");
-  }
-
-  GRPC_CHANNEL_STACK_UNREF(exec_ctx, chand->owning_stack, "resolver");
-  GRPC_ERROR_UNREF(state_error);
 }
 
 static void start_transport_op_locked(grpc_exec_ctx *exec_ctx, void *arg,
@@ -574,7 +600,7 @@ static void start_transport_op_locked(grpc_exec_ctx *exec_ctx, void *arg,
 
   if (op->send_ping != NULL) {
     if (chand->lb_policy == NULL) {
-      grpc_closure_sched(
+      GRPC_CLOSURE_SCHED(
           exec_ctx, op->send_ping,
           GRPC_ERROR_CREATE_FROM_STATIC_STRING("Ping with no load balancing"));
     } else {
@@ -593,9 +619,10 @@ static void start_transport_op_locked(grpc_exec_ctx *exec_ctx, void *arg,
       GRPC_RESOLVER_UNREF(exec_ctx, chand->resolver, "channel");
       chand->resolver = NULL;
       if (!chand->started_resolving) {
-        grpc_closure_list_fail_all(&chand->waiting_for_config_closures,
+        grpc_closure_list_fail_all(&chand->waiting_for_resolver_result_closures,
                                    GRPC_ERROR_REF(op->disconnect_with_error));
-        grpc_closure_list_sched(exec_ctx, &chand->waiting_for_config_closures);
+        GRPC_CLOSURE_LIST_SCHED(exec_ctx,
+                                &chand->waiting_for_resolver_result_closures);
       }
       if (chand->lb_policy != NULL) {
         grpc_pollset_set_del_pollset_set(exec_ctx,
@@ -609,7 +636,7 @@ static void start_transport_op_locked(grpc_exec_ctx *exec_ctx, void *arg,
   }
   GRPC_CHANNEL_STACK_UNREF(exec_ctx, chand->owning_stack, "start_transport_op");
 
-  grpc_closure_sched(exec_ctx, op->on_consumed, GRPC_ERROR_NONE);
+  GRPC_CLOSURE_SCHED(exec_ctx, op->on_consumed, GRPC_ERROR_NONE);
 }
 
 static void cc_start_transport_op(grpc_exec_ctx *exec_ctx,
@@ -625,10 +652,10 @@ static void cc_start_transport_op(grpc_exec_ctx *exec_ctx,
 
   op->handler_private.extra_arg = elem;
   GRPC_CHANNEL_STACK_REF(chand->owning_stack, "start_transport_op");
-  grpc_closure_sched(
+  GRPC_CLOSURE_SCHED(
       exec_ctx,
-      grpc_closure_init(&op->handler_private.closure, start_transport_op_locked,
-                        op, grpc_combiner_scheduler(chand->combiner, false)),
+      GRPC_CLOSURE_INIT(&op->handler_private.closure, start_transport_op_locked,
+                        op, grpc_combiner_scheduler(chand->combiner)),
       GRPC_ERROR_NONE);
 }
 
@@ -659,12 +686,18 @@ static grpc_error *cc_init_channel_elem(grpc_exec_ctx *exec_ctx,
   GPR_ASSERT(args->is_last);
   GPR_ASSERT(elem->filter == &grpc_client_channel_filter);
   // Initialize data members.
-  chand->combiner = grpc_combiner_create(NULL);
+  chand->combiner = grpc_combiner_create();
   gpr_mu_init(&chand->info_mu);
+  gpr_mu_init(&chand->external_connectivity_watcher_list_mu);
+
+  gpr_mu_lock(&chand->external_connectivity_watcher_list_mu);
+  chand->external_connectivity_watcher_list_head = NULL;
+  gpr_mu_unlock(&chand->external_connectivity_watcher_list_mu);
+
   chand->owning_stack = args->channel_stack;
-  grpc_closure_init(&chand->on_resolver_result_changed,
+  GRPC_CLOSURE_INIT(&chand->on_resolver_result_changed,
                     on_resolver_result_changed_locked, chand,
-                    grpc_combiner_scheduler(chand->combiner, false));
+                    grpc_combiner_scheduler(chand->combiner));
   chand->interested_parties = grpc_pollset_set_create();
   grpc_connectivity_state_init(&chand->state_tracker, GRPC_CHANNEL_IDLE,
                                "client_channel");
@@ -722,10 +755,9 @@ static void cc_destroy_channel_elem(grpc_exec_ctx *exec_ctx,
                                     grpc_channel_element *elem) {
   channel_data *chand = elem->channel_data;
   if (chand->resolver != NULL) {
-    grpc_closure_sched(
-        exec_ctx,
-        grpc_closure_create(shutdown_resolver_locked, chand->resolver,
-                            grpc_combiner_scheduler(chand->combiner, false)),
+    GRPC_CLOSURE_SCHED(
+        exec_ctx, GRPC_CLOSURE_CREATE(shutdown_resolver_locked, chand->resolver,
+                                      grpc_combiner_scheduler(chand->combiner)),
         GRPC_ERROR_NONE);
   }
   if (chand->client_channel_factory != NULL) {
@@ -749,16 +781,22 @@ static void cc_destroy_channel_elem(grpc_exec_ctx *exec_ctx,
   grpc_pollset_set_destroy(exec_ctx, chand->interested_parties);
   GRPC_COMBINER_UNREF(exec_ctx, chand->combiner, "client_channel");
   gpr_mu_destroy(&chand->info_mu);
+  gpr_mu_destroy(&chand->external_connectivity_watcher_list_mu);
 }
 
 /*************************************************************************
  * PER-CALL FUNCTIONS
  */
 
-#define GET_CALL(call_data) \
-  ((grpc_subchannel_call *)(gpr_atm_acq_load(&(call_data)->subchannel_call)))
-
-#define CANCELLED_CALL ((grpc_subchannel_call *)1)
+// Max number of batches that can be pending on a call at any given
+// time.  This includes:
+//   recv_initial_metadata
+//   send_initial_metadata
+//   recv_message
+//   send_message
+//   recv_trailing_metadata
+//   send_trailing_metadata
+#define MAX_WAITING_BATCHES 6
 
 /** Call data.  Holds a pointer to grpc_subchannel_call and the
     associated machinery to create such a pointer.
@@ -780,23 +818,22 @@ typedef struct client_channel_call_data {
   grpc_server_retry_throttle_data *retry_throttle_data;
   method_parameters *method_params;
 
-  grpc_error *cancel_error;
-
-  /** either 0 for no call, 1 for cancelled, or a pointer to a
-      grpc_subchannel_call */
-  gpr_atm subchannel_call;
+  /** either 0 for no call, a pointer to a grpc_subchannel_call (if the lowest
+      bit is 0), or a pointer to an error (if the lowest bit is 1) */
+  gpr_atm subchannel_call_or_error;
   gpr_arena *arena;
 
-  bool pick_pending;
+  grpc_lb_policy *lb_policy;  // Holds ref while LB pick is pending.
+  grpc_closure lb_pick_closure;
+
   grpc_connected_subchannel *connected_subchannel;
   grpc_call_context_element subchannel_call_context[GRPC_CONTEXT_COUNT];
   grpc_polling_entity *pollent;
 
-  grpc_transport_stream_op_batch **waiting_ops;
-  size_t waiting_ops_count;
-  size_t waiting_ops_capacity;
+  grpc_transport_stream_op_batch *waiting_for_pick_batches[MAX_WAITING_BATCHES];
+  size_t waiting_for_pick_batches_count;
 
-  grpc_closure next_step;
+  grpc_transport_stream_op_batch_payload *initial_metadata_payload;
 
   grpc_call_stack *owning_call;
 
@@ -806,65 +843,103 @@ typedef struct client_channel_call_data {
   grpc_closure *original_on_complete;
 } call_data;
 
+typedef struct {
+  grpc_subchannel_call *subchannel_call;
+  grpc_error *error;
+} call_or_error;
+
+static call_or_error get_call_or_error(call_data *p) {
+  gpr_atm c = gpr_atm_acq_load(&p->subchannel_call_or_error);
+  if (c == 0)
+    return (call_or_error){NULL, NULL};
+  else if (c & 1)
+    return (call_or_error){NULL, (grpc_error *)((c) & ~(gpr_atm)1)};
+  else
+    return (call_or_error){(grpc_subchannel_call *)c, NULL};
+}
+
+static bool set_call_or_error(call_data *p, call_or_error coe) {
+  // this should always be under a lock
+  call_or_error existing = get_call_or_error(p);
+  if (existing.error != GRPC_ERROR_NONE) {
+    GRPC_ERROR_UNREF(coe.error);
+    return false;
+  }
+  GPR_ASSERT(existing.subchannel_call == NULL);
+  if (coe.error != GRPC_ERROR_NONE) {
+    GPR_ASSERT(coe.subchannel_call == NULL);
+    gpr_atm_rel_store(&p->subchannel_call_or_error, 1 | (gpr_atm)coe.error);
+  } else {
+    GPR_ASSERT(coe.subchannel_call != NULL);
+    gpr_atm_rel_store(&p->subchannel_call_or_error,
+                      (gpr_atm)coe.subchannel_call);
+  }
+  return true;
+}
+
 grpc_subchannel_call *grpc_client_channel_get_subchannel_call(
     grpc_call_element *call_elem) {
-  grpc_subchannel_call *scc = GET_CALL((call_data *)call_elem->call_data);
-  return scc == CANCELLED_CALL ? NULL : scc;
+  return get_call_or_error(call_elem->call_data).subchannel_call;
 }
 
-static void add_waiting_locked(call_data *calld,
-                               grpc_transport_stream_op_batch *op) {
-  GPR_TIMER_BEGIN("add_waiting_locked", 0);
-  if (calld->waiting_ops_count == calld->waiting_ops_capacity) {
-    calld->waiting_ops_capacity = GPR_MAX(3, 2 * calld->waiting_ops_capacity);
-    calld->waiting_ops =
-        gpr_realloc(calld->waiting_ops,
-                    calld->waiting_ops_capacity * sizeof(*calld->waiting_ops));
-  }
-  calld->waiting_ops[calld->waiting_ops_count++] = op;
-  GPR_TIMER_END("add_waiting_locked", 0);
+static void waiting_for_pick_batches_add_locked(
+    call_data *calld, grpc_transport_stream_op_batch *batch) {
+  GPR_ASSERT(calld->waiting_for_pick_batches_count < MAX_WAITING_BATCHES);
+  calld->waiting_for_pick_batches[calld->waiting_for_pick_batches_count++] =
+      batch;
 }
 
-static void fail_locked(grpc_exec_ctx *exec_ctx, call_data *calld,
-                        grpc_error *error) {
-  size_t i;
-  for (i = 0; i < calld->waiting_ops_count; i++) {
+static void waiting_for_pick_batches_fail_locked(grpc_exec_ctx *exec_ctx,
+                                                 grpc_call_element *elem,
+                                                 grpc_error *error) {
+  call_data *calld = elem->call_data;
+  if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+    gpr_log(GPR_DEBUG,
+            "chand=%p calld=%p: failing %" PRIdPTR " pending batches: %s",
+            elem->channel_data, calld, calld->waiting_for_pick_batches_count,
+            grpc_error_string(error));
+  }
+  for (size_t i = 0; i < calld->waiting_for_pick_batches_count; ++i) {
     grpc_transport_stream_op_batch_finish_with_failure(
-        exec_ctx, calld->waiting_ops[i], GRPC_ERROR_REF(error));
+        exec_ctx, calld->waiting_for_pick_batches[i], GRPC_ERROR_REF(error));
   }
-  calld->waiting_ops_count = 0;
+  calld->waiting_for_pick_batches_count = 0;
   GRPC_ERROR_UNREF(error);
 }
 
-static void retry_waiting_locked(grpc_exec_ctx *exec_ctx, call_data *calld) {
-  if (calld->waiting_ops_count == 0) {
+static void waiting_for_pick_batches_resume_locked(grpc_exec_ctx *exec_ctx,
+                                                   grpc_call_element *elem) {
+  call_data *calld = elem->call_data;
+  if (calld->waiting_for_pick_batches_count == 0) return;
+  call_or_error coe = get_call_or_error(calld);
+  if (coe.error != GRPC_ERROR_NONE) {
+    waiting_for_pick_batches_fail_locked(exec_ctx, elem,
+                                         GRPC_ERROR_REF(coe.error));
     return;
   }
-
-  grpc_subchannel_call *call = GET_CALL(calld);
-  grpc_transport_stream_op_batch **ops = calld->waiting_ops;
-  size_t nops = calld->waiting_ops_count;
-  if (call == CANCELLED_CALL) {
-    fail_locked(exec_ctx, calld, GRPC_ERROR_CANCELLED);
-    return;
+  if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+    gpr_log(GPR_DEBUG, "chand=%p calld=%p: sending %" PRIdPTR
+                       " pending batches to subchannel_call=%p",
+            elem->channel_data, calld, calld->waiting_for_pick_batches_count,
+            coe.subchannel_call);
   }
-  calld->waiting_ops = NULL;
-  calld->waiting_ops_count = 0;
-  calld->waiting_ops_capacity = 0;
-  for (size_t i = 0; i < nops; i++) {
-    grpc_subchannel_call_process_op(exec_ctx, call, ops[i]);
+  for (size_t i = 0; i < calld->waiting_for_pick_batches_count; ++i) {
+    grpc_subchannel_call_process_op(exec_ctx, coe.subchannel_call,
+                                    calld->waiting_for_pick_batches[i]);
   }
-  gpr_free(ops);
+  calld->waiting_for_pick_batches_count = 0;
 }
 
-// Sets calld->method_params and calld->retry_throttle_data.
-// If the method params specify a timeout, populates
-// *per_method_deadline and returns true.
-static bool set_call_method_params_from_service_config_locked(
-    grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
-    gpr_timespec *per_method_deadline) {
+// Applies service config to the call.  Must be invoked once we know
+// that the resolver has returned results to the channel.
+static void apply_service_config_to_call_locked(grpc_exec_ctx *exec_ctx,
+                                                grpc_call_element *elem) {
   channel_data *chand = elem->channel_data;
   call_data *calld = elem->call_data;
+  if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+    gpr_log(GPR_DEBUG, "chand=%p calld=%p: applying service config to call",
+            chand, calld);
+  }
   if (chand->retry_throttle_data != NULL) {
     calld->retry_throttle_data =
         grpc_server_retry_throttle_data_ref(chand->retry_throttle_data);
@@ -874,175 +949,283 @@ static bool set_call_method_params_from_service_config_locked(
         exec_ctx, chand->method_params_table, calld->path);
     if (calld->method_params != NULL) {
       method_parameters_ref(calld->method_params);
-      if (gpr_time_cmp(calld->method_params->timeout,
+      // If the deadline from the service config is shorter than the one
+      // from the client API, reset the deadline timer.
+      if (chand->deadline_checking_enabled &&
+          gpr_time_cmp(calld->method_params->timeout,
                        gpr_time_0(GPR_TIMESPAN)) != 0) {
-        *per_method_deadline =
+        const gpr_timespec per_method_deadline =
             gpr_time_add(calld->call_start_time, calld->method_params->timeout);
-        return true;
+        if (gpr_time_cmp(per_method_deadline, calld->deadline) < 0) {
+          calld->deadline = per_method_deadline;
+          grpc_deadline_state_reset(exec_ctx, elem, calld->deadline);
+        }
       }
     }
   }
-  return false;
 }
 
-static void apply_final_configuration_locked(grpc_exec_ctx *exec_ctx,
-                                             grpc_call_element *elem) {
-  /* apply service-config level configuration to the call (now that we're
-   * certain it exists) */
+static void create_subchannel_call_locked(grpc_exec_ctx *exec_ctx,
+                                          grpc_call_element *elem,
+                                          grpc_error *error) {
   call_data *calld = elem->call_data;
-  channel_data *chand = elem->channel_data;
-  gpr_timespec per_method_deadline;
-  if (set_call_method_params_from_service_config_locked(exec_ctx, elem,
-                                                        &per_method_deadline)) {
-    // If the deadline from the service config is shorter than the one
-    // from the client API, reset the deadline timer.
-    if (chand->deadline_checking_enabled &&
-        gpr_time_cmp(per_method_deadline, calld->deadline) < 0) {
-      calld->deadline = per_method_deadline;
-      grpc_deadline_state_reset(exec_ctx, elem, calld->deadline);
-    }
+  grpc_subchannel_call *subchannel_call = NULL;
+  const grpc_connected_subchannel_call_args call_args = {
+      .pollent = calld->pollent,
+      .path = calld->path,
+      .start_time = calld->call_start_time,
+      .deadline = calld->deadline,
+      .arena = calld->arena,
+      .context = calld->subchannel_call_context};
+  grpc_error *new_error = grpc_connected_subchannel_create_call(
+      exec_ctx, calld->connected_subchannel, &call_args, &subchannel_call);
+  if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+    gpr_log(GPR_DEBUG, "chand=%p calld=%p: create subchannel_call=%p: error=%s",
+            elem->channel_data, calld, subchannel_call,
+            grpc_error_string(new_error));
+  }
+  GPR_ASSERT(set_call_or_error(
+      calld, (call_or_error){.subchannel_call = subchannel_call}));
+  if (new_error != GRPC_ERROR_NONE) {
+    new_error = grpc_error_add_child(new_error, error);
+    waiting_for_pick_batches_fail_locked(exec_ctx, elem, new_error);
+  } else {
+    waiting_for_pick_batches_resume_locked(exec_ctx, elem);
   }
+  GRPC_ERROR_UNREF(error);
 }
 
-static void subchannel_ready_locked(grpc_exec_ctx *exec_ctx, void *arg,
+static void subchannel_ready_locked(grpc_exec_ctx *exec_ctx,
+                                    grpc_call_element *elem,
                                     grpc_error *error) {
-  grpc_call_element *elem = arg;
   call_data *calld = elem->call_data;
   channel_data *chand = elem->channel_data;
-  GPR_ASSERT(calld->pick_pending);
-  calld->pick_pending = false;
   grpc_polling_entity_del_from_pollset_set(exec_ctx, calld->pollent,
                                            chand->interested_parties);
+  call_or_error coe = get_call_or_error(calld);
   if (calld->connected_subchannel == NULL) {
-    gpr_atm_no_barrier_store(&calld->subchannel_call, 1);
-    fail_locked(exec_ctx, calld,
-                GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
-                    "Failed to create subchannel", &error, 1));
-  } else if (GET_CALL(calld) == CANCELLED_CALL) {
+    // Failed to create subchannel.
+    grpc_error *failure =
+        error == GRPC_ERROR_NONE
+            ? GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+                  "Call dropped by load balancing policy")
+            : GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
+                  "Failed to create subchannel", &error, 1);
+    if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+      gpr_log(GPR_DEBUG,
+              "chand=%p calld=%p: failed to create subchannel: error=%s", chand,
+              calld, grpc_error_string(failure));
+    }
+    set_call_or_error(calld, (call_or_error){.error = GRPC_ERROR_REF(failure)});
+    waiting_for_pick_batches_fail_locked(exec_ctx, elem, failure);
+  } else if (coe.error != GRPC_ERROR_NONE) {
     /* already cancelled before subchannel became ready */
+    grpc_error *child_errors[] = {error, coe.error};
     grpc_error *cancellation_error =
         GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
-            "Cancelled before creating subchannel", &error, 1);
+            "Cancelled before creating subchannel", child_errors,
+            GPR_ARRAY_SIZE(child_errors));
     /* if due to deadline, attach the deadline exceeded status to the error */
     if (gpr_time_cmp(calld->deadline, gpr_now(GPR_CLOCK_MONOTONIC)) < 0) {
       cancellation_error =
           grpc_error_set_int(cancellation_error, GRPC_ERROR_INT_GRPC_STATUS,
                              GRPC_STATUS_DEADLINE_EXCEEDED);
     }
-    fail_locked(exec_ctx, calld, cancellation_error);
+    if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+      gpr_log(GPR_DEBUG,
+              "chand=%p calld=%p: cancelled before subchannel became ready: %s",
+              chand, calld, grpc_error_string(cancellation_error));
+    }
+    waiting_for_pick_batches_fail_locked(exec_ctx, elem, cancellation_error);
   } else {
     /* Create call on subchannel. */
-    grpc_subchannel_call *subchannel_call = NULL;
-    const grpc_connected_subchannel_call_args call_args = {
-        .pollent = calld->pollent,
-        .path = calld->path,
-        .start_time = calld->call_start_time,
-        .deadline = calld->deadline,
-        .arena = calld->arena,
-        .context = calld->subchannel_call_context};
-    grpc_error *new_error = grpc_connected_subchannel_create_call(
-        exec_ctx, calld->connected_subchannel, &call_args, &subchannel_call);
-    gpr_atm_rel_store(&calld->subchannel_call,
-                      (gpr_atm)(uintptr_t)subchannel_call);
-    if (new_error != GRPC_ERROR_NONE) {
-      new_error = grpc_error_add_child(new_error, error);
-      fail_locked(exec_ctx, calld, new_error);
-    } else {
-      retry_waiting_locked(exec_ctx, calld);
-    }
+    create_subchannel_call_locked(exec_ctx, elem, GRPC_ERROR_REF(error));
   }
   GRPC_CALL_STACK_UNREF(exec_ctx, calld->owning_call, "pick_subchannel");
+  GRPC_ERROR_UNREF(error);
 }
 
 static char *cc_get_peer(grpc_exec_ctx *exec_ctx, grpc_call_element *elem) {
   call_data *calld = elem->call_data;
-  grpc_subchannel_call *subchannel_call = GET_CALL(calld);
-  if (subchannel_call == NULL || subchannel_call == CANCELLED_CALL) {
+  grpc_subchannel_call *subchannel_call =
+      get_call_or_error(calld).subchannel_call;
+  if (subchannel_call == NULL) {
     return NULL;
   } else {
     return grpc_subchannel_call_get_peer(exec_ctx, subchannel_call);
   }
 }
 
+/** Return true if subchannel is available immediately (in which case
+    subchannel_ready_locked() should not be called), or false otherwise (in
+    which case subchannel_ready_locked() should be called when the subchannel
+    is available). */
+static bool pick_subchannel_locked(grpc_exec_ctx *exec_ctx,
+                                   grpc_call_element *elem);
+
 typedef struct {
-  grpc_metadata_batch *initial_metadata;
-  uint32_t initial_metadata_flags;
-  grpc_connected_subchannel **connected_subchannel;
-  grpc_call_context_element *subchannel_call_context;
-  grpc_closure *on_ready;
   grpc_call_element *elem;
+  bool cancelled;
   grpc_closure closure;
-} continue_picking_args;
+} pick_after_resolver_result_args;
 
-/** Return true if subchannel is available immediately (in which case on_ready
-    should not be called), or false otherwise (in which case on_ready should be
-    called when the subchannel is available). */
-static bool pick_subchannel_locked(
-    grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
-    grpc_metadata_batch *initial_metadata, uint32_t initial_metadata_flags,
-    grpc_connected_subchannel **connected_subchannel,
-    grpc_call_context_element *subchannel_call_context, grpc_closure *on_ready);
-
-static void continue_picking_locked(grpc_exec_ctx *exec_ctx, void *arg,
-                                    grpc_error *error) {
-  continue_picking_args *cpa = arg;
-  if (cpa->connected_subchannel == NULL) {
+static void pick_after_resolver_result_done_locked(grpc_exec_ctx *exec_ctx,
+                                                   void *arg,
+                                                   grpc_error *error) {
+  pick_after_resolver_result_args *args = arg;
+  if (args->cancelled) {
     /* cancelled, do nothing */
-  } else if (error != GRPC_ERROR_NONE) {
-    grpc_closure_sched(exec_ctx, cpa->on_ready, GRPC_ERROR_REF(error));
+    if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+      gpr_log(GPR_DEBUG, "call cancelled before resolver result");
+    }
   } else {
-    if (pick_subchannel_locked(exec_ctx, cpa->elem, cpa->initial_metadata,
-                               cpa->initial_metadata_flags,
-                               cpa->connected_subchannel,
-                               cpa->subchannel_call_context, cpa->on_ready)) {
-      grpc_closure_sched(exec_ctx, cpa->on_ready, GRPC_ERROR_NONE);
+    channel_data *chand = args->elem->channel_data;
+    call_data *calld = args->elem->call_data;
+    if (error != GRPC_ERROR_NONE) {
+      if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+        gpr_log(GPR_DEBUG, "chand=%p calld=%p: resolver failed to return data",
+                chand, calld);
+      }
+      subchannel_ready_locked(exec_ctx, args->elem, GRPC_ERROR_REF(error));
+    } else {
+      if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+        gpr_log(GPR_DEBUG, "chand=%p calld=%p: resolver returned, doing pick",
+                chand, calld);
+      }
+      if (pick_subchannel_locked(exec_ctx, args->elem)) {
+        subchannel_ready_locked(exec_ctx, args->elem, GRPC_ERROR_NONE);
+      }
     }
   }
-  gpr_free(cpa);
+  gpr_free(args);
 }
 
-static void cancel_pick_locked(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
-                               grpc_error *error) {
+static void pick_after_resolver_result_start_locked(grpc_exec_ctx *exec_ctx,
+                                                    grpc_call_element *elem) {
   channel_data *chand = elem->channel_data;
   call_data *calld = elem->call_data;
-  if (chand->lb_policy != NULL) {
-    grpc_lb_policy_cancel_pick_locked(exec_ctx, chand->lb_policy,
-                                      &calld->connected_subchannel,
-                                      GRPC_ERROR_REF(error));
-  }
-  for (grpc_closure *closure = chand->waiting_for_config_closures.head;
+  if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+    gpr_log(GPR_DEBUG,
+            "chand=%p calld=%p: deferring pick pending resolver result", chand,
+            calld);
+  }
+  pick_after_resolver_result_args *args =
+      (pick_after_resolver_result_args *)gpr_zalloc(sizeof(*args));
+  args->elem = elem;
+  GRPC_CLOSURE_INIT(&args->closure, pick_after_resolver_result_done_locked,
+                    args, grpc_combiner_scheduler(chand->combiner));
+  grpc_closure_list_append(&chand->waiting_for_resolver_result_closures,
+                           &args->closure, GRPC_ERROR_NONE);
+}
+
+static void pick_after_resolver_result_cancel_locked(grpc_exec_ctx *exec_ctx,
+                                                     grpc_call_element *elem,
+                                                     grpc_error *error) {
+  channel_data *chand = elem->channel_data;
+  call_data *calld = elem->call_data;
+  // If we don't yet have a resolver result, then a closure for
+  // pick_after_resolver_result_done_locked() will have been added to
+  // chand->waiting_for_resolver_result_closures, and it may not be invoked
+  // until after this call has been destroyed.  We mark the operation as
+  // cancelled, so that when pick_after_resolver_result_done_locked()
+  // is called, it will be a no-op.  We also immediately invoke
+  // subchannel_ready_locked() to propagate the error back to the caller.
+  for (grpc_closure *closure = chand->waiting_for_resolver_result_closures.head;
        closure != NULL; closure = closure->next_data.next) {
-    continue_picking_args *cpa = closure->cb_arg;
-    if (cpa->connected_subchannel == &calld->connected_subchannel) {
-      cpa->connected_subchannel = NULL;
-      grpc_closure_sched(exec_ctx, cpa->on_ready,
-                         GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
-                             "Pick cancelled", &error, 1));
+    pick_after_resolver_result_args *args = closure->cb_arg;
+    if (!args->cancelled && args->elem == elem) {
+      if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+        gpr_log(GPR_DEBUG,
+                "chand=%p calld=%p: "
+                "cancelling pick waiting for resolver result",
+                chand, calld);
+      }
+      args->cancelled = true;
+      subchannel_ready_locked(exec_ctx, elem,
+                              GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
+                                  "Pick cancelled", &error, 1));
     }
   }
   GRPC_ERROR_UNREF(error);
 }
 
-static bool pick_subchannel_locked(
-    grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
-    grpc_metadata_batch *initial_metadata, uint32_t initial_metadata_flags,
-    grpc_connected_subchannel **connected_subchannel,
-    grpc_call_context_element *subchannel_call_context,
-    grpc_closure *on_ready) {
-  GPR_TIMER_BEGIN("pick_subchannel", 0);
+// Callback invoked by grpc_lb_policy_pick_locked() for async picks.
+// Unrefs the LB policy after invoking subchannel_ready_locked().
+static void pick_callback_done_locked(grpc_exec_ctx *exec_ctx, void *arg,
+                                      grpc_error *error) {
+  grpc_call_element *elem = arg;
+  channel_data *chand = elem->channel_data;
+  call_data *calld = elem->call_data;
+  if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+    gpr_log(GPR_DEBUG, "chand=%p calld=%p: pick completed asynchronously",
+            chand, calld);
+  }
+  GPR_ASSERT(calld->lb_policy != NULL);
+  GRPC_LB_POLICY_UNREF(exec_ctx, calld->lb_policy, "pick_subchannel");
+  calld->lb_policy = NULL;
+  subchannel_ready_locked(exec_ctx, elem, GRPC_ERROR_REF(error));
+}
 
+// Takes a ref to chand->lb_policy and calls grpc_lb_policy_pick_locked().
+// If the pick was completed synchronously, unrefs the LB policy and
+// returns true.
+static bool pick_callback_start_locked(grpc_exec_ctx *exec_ctx,
+                                       grpc_call_element *elem,
+                                       const grpc_lb_policy_pick_args *inputs) {
   channel_data *chand = elem->channel_data;
   call_data *calld = elem->call_data;
+  if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+    gpr_log(GPR_DEBUG, "chand=%p calld=%p: starting pick on lb_policy=%p",
+            chand, calld, chand->lb_policy);
+  }
+  // Keep a ref to the LB policy in calld while the pick is pending.
+  GRPC_LB_POLICY_REF(chand->lb_policy, "pick_subchannel");
+  calld->lb_policy = chand->lb_policy;
+  GRPC_CLOSURE_INIT(&calld->lb_pick_closure, pick_callback_done_locked, elem,
+                    grpc_combiner_scheduler(chand->combiner));
+  const bool pick_done = grpc_lb_policy_pick_locked(
+      exec_ctx, chand->lb_policy, inputs, &calld->connected_subchannel,
+      calld->subchannel_call_context, NULL, &calld->lb_pick_closure);
+  if (pick_done) {
+    /* synchronous grpc_lb_policy_pick call. Unref the LB policy. */
+    if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+      gpr_log(GPR_DEBUG, "chand=%p calld=%p: pick completed synchronously",
+              chand, calld);
+    }
+    GRPC_LB_POLICY_UNREF(exec_ctx, calld->lb_policy, "pick_subchannel");
+    calld->lb_policy = NULL;
+  }
+  return pick_done;
+}
 
-  GPR_ASSERT(connected_subchannel);
+static void pick_callback_cancel_locked(grpc_exec_ctx *exec_ctx,
+                                        grpc_call_element *elem,
+                                        grpc_error *error) {
+  channel_data *chand = elem->channel_data;
+  call_data *calld = elem->call_data;
+  GPR_ASSERT(calld->lb_policy != NULL);
+  if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+    gpr_log(GPR_DEBUG, "chand=%p calld=%p: cancelling pick from LB policy %p",
+            chand, calld, calld->lb_policy);
+  }
+  grpc_lb_policy_cancel_pick_locked(exec_ctx, calld->lb_policy,
+                                    &calld->connected_subchannel, error);
+}
 
+static bool pick_subchannel_locked(grpc_exec_ctx *exec_ctx,
+                                   grpc_call_element *elem) {
+  GPR_TIMER_BEGIN("pick_subchannel", 0);
+  channel_data *chand = elem->channel_data;
+  call_data *calld = elem->call_data;
+  bool pick_done = false;
   if (chand->lb_policy != NULL) {
-    apply_final_configuration_locked(exec_ctx, elem);
-    grpc_lb_policy *lb_policy = chand->lb_policy;
-    GRPC_LB_POLICY_REF(lb_policy, "pick_subchannel");
+    apply_service_config_to_call_locked(exec_ctx, elem);
     // If the application explicitly set wait_for_ready, use that.
     // Otherwise, if the service config specified a value for this
     // method, use that.
+    uint32_t initial_metadata_flags =
+        calld->initial_metadata_payload->send_initial_metadata
+            .send_initial_metadata_flags;
     const bool wait_for_ready_set_from_api =
         initial_metadata_flags &
         GRPC_INITIAL_METADATA_WAIT_FOR_READY_EXPLICITLY_SET;
@@ -1058,160 +1241,108 @@ static bool pick_subchannel_locked(
       }
     }
     const grpc_lb_policy_pick_args inputs = {
-        initial_metadata, initial_metadata_flags, &calld->lb_token_mdelem};
-
-    // Wrap the user-provided callback in order to hold a strong reference to
-    // the LB policy for the duration of the pick.
-    wrapped_on_pick_closure_arg *w_on_pick_arg =
-        gpr_zalloc(sizeof(*w_on_pick_arg));
-    grpc_closure_init(&w_on_pick_arg->wrapper_closure,
-                      wrapped_on_pick_closure_cb, w_on_pick_arg,
-                      grpc_schedule_on_exec_ctx);
-    w_on_pick_arg->wrapped_closure = on_ready;
-    GRPC_LB_POLICY_REF(lb_policy, "pick_subchannel_wrapping");
-    w_on_pick_arg->lb_policy = lb_policy;
-    const bool pick_done = grpc_lb_policy_pick_locked(
-        exec_ctx, lb_policy, &inputs, connected_subchannel,
-        subchannel_call_context, NULL, &w_on_pick_arg->wrapper_closure);
-    if (pick_done) {
-      /* synchronous grpc_lb_policy_pick call. Unref the LB policy. */
-      GRPC_LB_POLICY_UNREF(exec_ctx, w_on_pick_arg->lb_policy,
-                           "pick_subchannel_wrapping");
-      gpr_free(w_on_pick_arg);
+        calld->initial_metadata_payload->send_initial_metadata
+            .send_initial_metadata,
+        initial_metadata_flags, &calld->lb_token_mdelem};
+    pick_done = pick_callback_start_locked(exec_ctx, elem, &inputs);
+  } else if (chand->resolver != NULL) {
+    if (!chand->started_resolving) {
+      start_resolving_locked(exec_ctx, chand);
     }
-    GRPC_LB_POLICY_UNREF(exec_ctx, lb_policy, "pick_subchannel");
-    GPR_TIMER_END("pick_subchannel", 0);
-    return pick_done;
-  }
-  if (chand->resolver != NULL && !chand->started_resolving) {
-    chand->started_resolving = true;
-    GRPC_CHANNEL_STACK_REF(chand->owning_stack, "resolver");
-    grpc_resolver_next_locked(exec_ctx, chand->resolver,
-                              &chand->resolver_result,
-                              &chand->on_resolver_result_changed);
-  }
-  if (chand->resolver != NULL) {
-    continue_picking_args *cpa = gpr_malloc(sizeof(*cpa));
-    cpa->initial_metadata = initial_metadata;
-    cpa->initial_metadata_flags = initial_metadata_flags;
-    cpa->connected_subchannel = connected_subchannel;
-    cpa->subchannel_call_context = subchannel_call_context;
-    cpa->on_ready = on_ready;
-    cpa->elem = elem;
-    grpc_closure_init(&cpa->closure, continue_picking_locked, cpa,
-                      grpc_combiner_scheduler(chand->combiner, true));
-    grpc_closure_list_append(&chand->waiting_for_config_closures, &cpa->closure,
-                             GRPC_ERROR_NONE);
+    pick_after_resolver_result_start_locked(exec_ctx, elem);
   } else {
-    grpc_closure_sched(exec_ctx, on_ready,
-                       GRPC_ERROR_CREATE_FROM_STATIC_STRING("Disconnected"));
+    subchannel_ready_locked(
+        exec_ctx, elem, GRPC_ERROR_CREATE_FROM_STATIC_STRING("Disconnected"));
   }
-
   GPR_TIMER_END("pick_subchannel", 0);
-  return false;
+  return pick_done;
 }
 
-static void start_transport_stream_op_batch_locked_inner(
-    grpc_exec_ctx *exec_ctx, grpc_transport_stream_op_batch *op,
-    grpc_call_element *elem) {
-  channel_data *chand = elem->channel_data;
+static void start_transport_stream_op_batch_locked(grpc_exec_ctx *exec_ctx,
+                                                   void *arg,
+                                                   grpc_error *error_ignored) {
+  GPR_TIMER_BEGIN("start_transport_stream_op_batch_locked", 0);
+  grpc_transport_stream_op_batch *batch = arg;
+  grpc_call_element *elem = batch->handler_private.extra_arg;
   call_data *calld = elem->call_data;
-  grpc_subchannel_call *call;
-
+  channel_data *chand = elem->channel_data;
   /* need to recheck that another thread hasn't set the call */
-  call = GET_CALL(calld);
-  if (call == CANCELLED_CALL) {
+  call_or_error coe = get_call_or_error(calld);
+  if (coe.error != GRPC_ERROR_NONE) {
+    if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+      gpr_log(GPR_DEBUG, "chand=%p calld=%p: failing batch with error: %s",
+              chand, calld, grpc_error_string(coe.error));
+    }
     grpc_transport_stream_op_batch_finish_with_failure(
-        exec_ctx, op, GRPC_ERROR_REF(calld->cancel_error));
-    /* early out */
-    return;
-  }
-  if (call != NULL) {
-    grpc_subchannel_call_process_op(exec_ctx, call, op);
-    /* early out */
-    return;
-  }
-  /* if this is a cancellation, then we can raise our cancelled flag */
-  if (op->cancel_stream) {
-    if (!gpr_atm_rel_cas(&calld->subchannel_call, 0,
-                         (gpr_atm)(uintptr_t)CANCELLED_CALL)) {
-      /* recurse to retry */
-      start_transport_stream_op_batch_locked_inner(exec_ctx, op, elem);
-      /* early out */
-      return;
+        exec_ctx, batch, GRPC_ERROR_REF(coe.error));
+    goto done;
+  }
+  if (coe.subchannel_call != NULL) {
+    if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+      gpr_log(GPR_DEBUG,
+              "chand=%p calld=%p: sending batch to subchannel_call=%p", chand,
+              calld, coe.subchannel_call);
+    }
+    grpc_subchannel_call_process_op(exec_ctx, coe.subchannel_call, batch);
+    goto done;
+  }
+  // Add to waiting-for-pick list.  If we succeed in getting a
+  // subchannel call below, we'll handle this batch (along with any
+  // other waiting batches) in waiting_for_pick_batches_resume_locked().
+  waiting_for_pick_batches_add_locked(calld, batch);
+  // If this is a cancellation, cancel the pending pick (if any) and
+  // fail any pending batches.
+  if (batch->cancel_stream) {
+    grpc_error *error = batch->payload->cancel_stream.cancel_error;
+    if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+      gpr_log(GPR_DEBUG, "chand=%p calld=%p: recording cancel_error=%s", chand,
+              calld, grpc_error_string(error));
+    }
+    /* Stash a copy of cancel_error in our call data, so that we can use
+       it for subsequent operations.  This ensures that if the call is
+       cancelled before any batches are passed down (e.g., if the deadline
+       is in the past when the call starts), we can return the right
+       error to the caller when the first batch does get passed down. */
+    set_call_or_error(calld, (call_or_error){.error = GRPC_ERROR_REF(error)});
+    if (calld->lb_policy != NULL) {
+      pick_callback_cancel_locked(exec_ctx, elem, GRPC_ERROR_REF(error));
     } else {
-      /* Stash a copy of cancel_error in our call data, so that we can use
-         it for subsequent operations.  This ensures that if the call is
-         cancelled before any ops are passed down (e.g., if the deadline
-         is in the past when the call starts), we can return the right
-         error to the caller when the first op does get passed down. */
-      calld->cancel_error =
-          GRPC_ERROR_REF(op->payload->cancel_stream.cancel_error);
-      if (calld->pick_pending) {
-        cancel_pick_locked(
-            exec_ctx, elem,
-            GRPC_ERROR_REF(op->payload->cancel_stream.cancel_error));
-      } else {
-        fail_locked(exec_ctx, calld,
-                    GRPC_ERROR_REF(op->payload->cancel_stream.cancel_error));
-      }
-      grpc_transport_stream_op_batch_finish_with_failure(
-          exec_ctx, op,
-          GRPC_ERROR_REF(op->payload->cancel_stream.cancel_error));
-      /* early out */
-      return;
+      pick_after_resolver_result_cancel_locked(exec_ctx, elem,
+                                               GRPC_ERROR_REF(error));
     }
+    waiting_for_pick_batches_fail_locked(exec_ctx, elem, GRPC_ERROR_REF(error));
+    goto done;
   }
   /* if we don't have a subchannel, try to get one */
-  if (!calld->pick_pending && calld->connected_subchannel == NULL &&
-      op->send_initial_metadata) {
-    calld->pick_pending = true;
-    grpc_closure_init(&calld->next_step, subchannel_ready_locked, elem,
-                      grpc_combiner_scheduler(chand->combiner, true));
+  if (batch->send_initial_metadata) {
+    GPR_ASSERT(calld->connected_subchannel == NULL);
+    calld->initial_metadata_payload = batch->payload;
     GRPC_CALL_STACK_REF(calld->owning_call, "pick_subchannel");
     /* If a subchannel is not available immediately, the polling entity from
        call_data should be provided to channel_data's interested_parties, so
        that IO of the lb_policy and resolver could be done under it. */
-    if (pick_subchannel_locked(
-            exec_ctx, elem,
-            op->payload->send_initial_metadata.send_initial_metadata,
-            op->payload->send_initial_metadata.send_initial_metadata_flags,
-            &calld->connected_subchannel, calld->subchannel_call_context,
-            &calld->next_step)) {
-      calld->pick_pending = false;
+    if (pick_subchannel_locked(exec_ctx, elem)) {
+      // Pick was returned synchronously.
       GRPC_CALL_STACK_UNREF(exec_ctx, calld->owning_call, "pick_subchannel");
+      if (calld->connected_subchannel == NULL) {
+        grpc_error *error = GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+            "Call dropped by load balancing policy");
+        set_call_or_error(calld,
+                          (call_or_error){.error = GRPC_ERROR_REF(error)});
+        waiting_for_pick_batches_fail_locked(exec_ctx, elem, error);
+      } else {
+        // Create subchannel call.
+        create_subchannel_call_locked(exec_ctx, elem, GRPC_ERROR_NONE);
+      }
     } else {
       grpc_polling_entity_add_to_pollset_set(exec_ctx, calld->pollent,
                                              chand->interested_parties);
     }
   }
-  /* if we've got a subchannel, then let's ask it to create a call */
-  if (!calld->pick_pending && calld->connected_subchannel != NULL) {
-    grpc_subchannel_call *subchannel_call = NULL;
-    const grpc_connected_subchannel_call_args call_args = {
-        .pollent = calld->pollent,
-        .path = calld->path,
-        .start_time = calld->call_start_time,
-        .deadline = calld->deadline,
-        .arena = calld->arena,
-        .context = calld->subchannel_call_context};
-    grpc_error *error = grpc_connected_subchannel_create_call(
-        exec_ctx, calld->connected_subchannel, &call_args, &subchannel_call);
-    gpr_atm_rel_store(&calld->subchannel_call,
-                      (gpr_atm)(uintptr_t)subchannel_call);
-    if (error != GRPC_ERROR_NONE) {
-      fail_locked(exec_ctx, calld, GRPC_ERROR_REF(error));
-      grpc_transport_stream_op_batch_finish_with_failure(exec_ctx, op, error);
-    } else {
-      retry_waiting_locked(exec_ctx, calld);
-      /* recurse to retry */
-      start_transport_stream_op_batch_locked_inner(exec_ctx, op, elem);
-    }
-    /* early out */
-    return;
-  }
-  /* nothing to be done but wait */
-  add_waiting_locked(calld, op);
+done:
+  GRPC_CALL_STACK_UNREF(exec_ctx, calld->owning_call,
+                        "start_transport_stream_op_batch");
+  GPR_TIMER_END("start_transport_stream_op_batch_locked", 0);
 }
 
 static void on_complete(grpc_exec_ctx *exec_ctx, void *arg, grpc_error *error) {
@@ -1230,34 +1361,10 @@ static void on_complete(grpc_exec_ctx *exec_ctx, void *arg, grpc_error *error) {
           calld->retry_throttle_data);
     }
   }
-  grpc_closure_run(exec_ctx, calld->original_on_complete,
+  GRPC_CLOSURE_RUN(exec_ctx, calld->original_on_complete,
                    GRPC_ERROR_REF(error));
 }
 
-static void start_transport_stream_op_batch_locked(grpc_exec_ctx *exec_ctx,
-                                                   void *arg,
-                                                   grpc_error *error_ignored) {
-  GPR_TIMER_BEGIN("start_transport_stream_op_batch_locked", 0);
-
-  grpc_transport_stream_op_batch *op = arg;
-  grpc_call_element *elem = op->handler_private.extra_arg;
-  call_data *calld = elem->call_data;
-
-  if (op->recv_trailing_metadata) {
-    GPR_ASSERT(op->on_complete != NULL);
-    calld->original_on_complete = op->on_complete;
-    grpc_closure_init(&calld->on_complete, on_complete, elem,
-                      grpc_schedule_on_exec_ctx);
-    op->on_complete = &calld->on_complete;
-  }
-
-  start_transport_stream_op_batch_locked_inner(exec_ctx, op, elem);
-
-  GRPC_CALL_STACK_UNREF(exec_ctx, calld->owning_call,
-                        "start_transport_stream_op_batch");
-  GPR_TIMER_END("start_transport_stream_op_batch_locked", 0);
-}
-
 /* The logic here is fairly complicated, due to (a) the fact that we
    need to handle the case where we receive the send op before the
    initial metadata op, and (b) the need for efficiency, especially in
@@ -1268,39 +1375,59 @@ static void start_transport_stream_op_batch_locked(grpc_exec_ctx *exec_ctx,
    If it has, we proceed on the fast path. */
 static void cc_start_transport_stream_op_batch(
     grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
-    grpc_transport_stream_op_batch *op) {
+    grpc_transport_stream_op_batch *batch) {
   call_data *calld = elem->call_data;
   channel_data *chand = elem->channel_data;
-  GRPC_CALL_LOG_OP(GPR_INFO, elem, op);
+  if (GRPC_TRACER_ON(grpc_client_channel_trace) ||
+      GRPC_TRACER_ON(grpc_trace_channel)) {
+    grpc_call_log_op(GPR_INFO, elem, batch);
+  }
   if (chand->deadline_checking_enabled) {
     grpc_deadline_state_client_start_transport_stream_op_batch(exec_ctx, elem,
-                                                               op);
+                                                               batch);
+  }
+  // Intercept on_complete for recv_trailing_metadata so that we can
+  // check retry throttle status.
+  if (batch->recv_trailing_metadata) {
+    GPR_ASSERT(batch->on_complete != NULL);
+    calld->original_on_complete = batch->on_complete;
+    GRPC_CLOSURE_INIT(&calld->on_complete, on_complete, elem,
+                      grpc_schedule_on_exec_ctx);
+    batch->on_complete = &calld->on_complete;
   }
   /* try to (atomically) get the call */
-  grpc_subchannel_call *call = GET_CALL(calld);
+  call_or_error coe = get_call_or_error(calld);
   GPR_TIMER_BEGIN("cc_start_transport_stream_op_batch", 0);
-  if (call == CANCELLED_CALL) {
+  if (coe.error != GRPC_ERROR_NONE) {
+    if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+      gpr_log(GPR_DEBUG, "chand=%p calld=%p: failing batch with error: %s",
+              chand, calld, grpc_error_string(coe.error));
+    }
     grpc_transport_stream_op_batch_finish_with_failure(
-        exec_ctx, op, GRPC_ERROR_REF(calld->cancel_error));
-    GPR_TIMER_END("cc_start_transport_stream_op_batch", 0);
-    /* early out */
-    return;
-  }
-  if (call != NULL) {
-    grpc_subchannel_call_process_op(exec_ctx, call, op);
-    GPR_TIMER_END("cc_start_transport_stream_op_batch", 0);
-    /* early out */
-    return;
+        exec_ctx, batch, GRPC_ERROR_REF(coe.error));
+    goto done;
+  }
+  if (coe.subchannel_call != NULL) {
+    if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+      gpr_log(GPR_DEBUG,
+              "chand=%p calld=%p: sending batch to subchannel_call=%p", chand,
+              calld, coe.subchannel_call);
+    }
+    grpc_subchannel_call_process_op(exec_ctx, coe.subchannel_call, batch);
+    goto done;
   }
   /* we failed; lock and figure out what to do */
+  if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
+    gpr_log(GPR_DEBUG, "chand=%p calld=%p: entering combiner", chand, calld);
+  }
   GRPC_CALL_STACK_REF(calld->owning_call, "start_transport_stream_op_batch");
-  op->handler_private.extra_arg = elem;
-  grpc_closure_sched(
-      exec_ctx,
-      grpc_closure_init(&op->handler_private.closure,
-                        start_transport_stream_op_batch_locked, op,
-                        grpc_combiner_scheduler(chand->combiner, false)),
+  batch->handler_private.extra_arg = elem;
+  GRPC_CLOSURE_SCHED(
+      exec_ctx, GRPC_CLOSURE_INIT(&batch->handler_private.closure,
+                                  start_transport_stream_op_batch_locked, batch,
+                                  grpc_combiner_scheduler(chand->combiner)),
       GRPC_ERROR_NONE);
+done:
   GPR_TIMER_END("cc_start_transport_stream_op_batch", 0);
 }
 
@@ -1336,15 +1463,17 @@ static void cc_destroy_call_elem(grpc_exec_ctx *exec_ctx,
   if (calld->method_params != NULL) {
     method_parameters_unref(calld->method_params);
   }
-  GRPC_ERROR_UNREF(calld->cancel_error);
-  grpc_subchannel_call *call = GET_CALL(calld);
-  if (call != NULL && call != CANCELLED_CALL) {
-    grpc_subchannel_call_set_cleanup_closure(call, then_schedule_closure);
+  call_or_error coe = get_call_or_error(calld);
+  GRPC_ERROR_UNREF(coe.error);
+  if (coe.subchannel_call != NULL) {
+    grpc_subchannel_call_set_cleanup_closure(coe.subchannel_call,
+                                             then_schedule_closure);
     then_schedule_closure = NULL;
-    GRPC_SUBCHANNEL_CALL_UNREF(exec_ctx, call, "client_channel_destroy_call");
+    GRPC_SUBCHANNEL_CALL_UNREF(exec_ctx, coe.subchannel_call,
+                               "client_channel_destroy_call");
   }
-  GPR_ASSERT(!calld->pick_pending);
-  GPR_ASSERT(calld->waiting_ops_count == 0);
+  GPR_ASSERT(calld->lb_policy == NULL);
+  GPR_ASSERT(calld->waiting_for_pick_batches_count == 0);
   if (calld->connected_subchannel != NULL) {
     GRPC_CONNECTED_SUBCHANNEL_UNREF(exec_ctx, calld->connected_subchannel,
                                     "picked");
@@ -1355,8 +1484,7 @@ static void cc_destroy_call_elem(grpc_exec_ctx *exec_ctx,
           calld->subchannel_call_context[i].value);
     }
   }
-  gpr_free(calld->waiting_ops);
-  grpc_closure_sched(exec_ctx, then_schedule_closure, GRPC_ERROR_NONE);
+  GRPC_CLOSURE_SCHED(exec_ctx, then_schedule_closure, GRPC_ERROR_NONE);
 }
 
 static void cc_set_pollset_or_pollset_set(grpc_exec_ctx *exec_ctx,
@@ -1393,11 +1521,7 @@ static void try_to_connect_locked(grpc_exec_ctx *exec_ctx, void *arg,
   } else {
     chand->exit_idle_when_lb_policy_arrives = true;
     if (!chand->started_resolving && chand->resolver != NULL) {
-      GRPC_CHANNEL_STACK_REF(chand->owning_stack, "resolver");
-      chand->started_resolving = true;
-      grpc_resolver_next_locked(exec_ctx, chand->resolver,
-                                &chand->resolver_result,
-                                &chand->on_resolver_result_changed);
+      start_resolving_locked(exec_ctx, chand);
     }
   }
   GRPC_CHANNEL_STACK_UNREF(exec_ctx, chand->owning_stack, "try_to_connect");
@@ -1410,59 +1534,145 @@ grpc_connectivity_state grpc_client_channel_check_connectivity_state(
       grpc_connectivity_state_check(&chand->state_tracker);
   if (out == GRPC_CHANNEL_IDLE && try_to_connect) {
     GRPC_CHANNEL_STACK_REF(chand->owning_stack, "try_to_connect");
-    grpc_closure_sched(
-        exec_ctx,
-        grpc_closure_create(try_to_connect_locked, chand,
-                            grpc_combiner_scheduler(chand->combiner, false)),
+    GRPC_CLOSURE_SCHED(
+        exec_ctx, GRPC_CLOSURE_CREATE(try_to_connect_locked, chand,
+                                      grpc_combiner_scheduler(chand->combiner)),
         GRPC_ERROR_NONE);
   }
   return out;
 }
 
-typedef struct {
+typedef struct external_connectivity_watcher {
   channel_data *chand;
-  grpc_pollset *pollset;
+  grpc_polling_entity pollent;
   grpc_closure *on_complete;
+  grpc_closure *watcher_timer_init;
   grpc_connectivity_state *state;
   grpc_closure my_closure;
+  struct external_connectivity_watcher *next;
 } external_connectivity_watcher;
 
+static external_connectivity_watcher *lookup_external_connectivity_watcher(
+    channel_data *chand, grpc_closure *on_complete) {
+  gpr_mu_lock(&chand->external_connectivity_watcher_list_mu);
+  external_connectivity_watcher *w =
+      chand->external_connectivity_watcher_list_head;
+  while (w != NULL && w->on_complete != on_complete) {
+    w = w->next;
+  }
+  gpr_mu_unlock(&chand->external_connectivity_watcher_list_mu);
+  return w;
+}
+
+static void external_connectivity_watcher_list_append(
+    channel_data *chand, external_connectivity_watcher *w) {
+  GPR_ASSERT(!lookup_external_connectivity_watcher(chand, w->on_complete));
+
+  gpr_mu_lock(&w->chand->external_connectivity_watcher_list_mu);
+  GPR_ASSERT(!w->next);
+  w->next = chand->external_connectivity_watcher_list_head;
+  chand->external_connectivity_watcher_list_head = w;
+  gpr_mu_unlock(&w->chand->external_connectivity_watcher_list_mu);
+}
+
+static void external_connectivity_watcher_list_remove(
+    channel_data *chand, external_connectivity_watcher *too_remove) {
+  GPR_ASSERT(
+      lookup_external_connectivity_watcher(chand, too_remove->on_complete));
+  gpr_mu_lock(&chand->external_connectivity_watcher_list_mu);
+  if (too_remove == chand->external_connectivity_watcher_list_head) {
+    chand->external_connectivity_watcher_list_head = too_remove->next;
+    gpr_mu_unlock(&chand->external_connectivity_watcher_list_mu);
+    return;
+  }
+  external_connectivity_watcher *w =
+      chand->external_connectivity_watcher_list_head;
+  while (w != NULL) {
+    if (w->next == too_remove) {
+      w->next = w->next->next;
+      gpr_mu_unlock(&chand->external_connectivity_watcher_list_mu);
+      return;
+    }
+    w = w->next;
+  }
+  GPR_UNREACHABLE_CODE(return );
+}
+
+int grpc_client_channel_num_external_connectivity_watchers(
+    grpc_channel_element *elem) {
+  channel_data *chand = elem->channel_data;
+  int count = 0;
+
+  gpr_mu_lock(&chand->external_connectivity_watcher_list_mu);
+  external_connectivity_watcher *w =
+      chand->external_connectivity_watcher_list_head;
+  while (w != NULL) {
+    count++;
+    w = w->next;
+  }
+  gpr_mu_unlock(&chand->external_connectivity_watcher_list_mu);
+
+  return count;
+}
+
 static void on_external_watch_complete(grpc_exec_ctx *exec_ctx, void *arg,
                                        grpc_error *error) {
   external_connectivity_watcher *w = arg;
   grpc_closure *follow_up = w->on_complete;
-  grpc_pollset_set_del_pollset(exec_ctx, w->chand->interested_parties,
-                               w->pollset);
+  grpc_polling_entity_del_from_pollset_set(exec_ctx, &w->pollent,
+                                           w->chand->interested_parties);
   GRPC_CHANNEL_STACK_UNREF(exec_ctx, w->chand->owning_stack,
                            "external_connectivity_watcher");
+  external_connectivity_watcher_list_remove(w->chand, w);
   gpr_free(w);
-  grpc_closure_run(exec_ctx, follow_up, GRPC_ERROR_REF(error));
+  GRPC_CLOSURE_RUN(exec_ctx, follow_up, GRPC_ERROR_REF(error));
 }
 
 static void watch_connectivity_state_locked(grpc_exec_ctx *exec_ctx, void *arg,
                                             grpc_error *error_ignored) {
   external_connectivity_watcher *w = arg;
-  grpc_closure_init(&w->my_closure, on_external_watch_complete, w,
-                    grpc_schedule_on_exec_ctx);
-  grpc_connectivity_state_notify_on_state_change(
-      exec_ctx, &w->chand->state_tracker, w->state, &w->my_closure);
+  external_connectivity_watcher *found = NULL;
+  if (w->state != NULL) {
+    external_connectivity_watcher_list_append(w->chand, w);
+    GRPC_CLOSURE_RUN(exec_ctx, w->watcher_timer_init, GRPC_ERROR_NONE);
+    GRPC_CLOSURE_INIT(&w->my_closure, on_external_watch_complete, w,
+                      grpc_schedule_on_exec_ctx);
+    grpc_connectivity_state_notify_on_state_change(
+        exec_ctx, &w->chand->state_tracker, w->state, &w->my_closure);
+  } else {
+    GPR_ASSERT(w->watcher_timer_init == NULL);
+    found = lookup_external_connectivity_watcher(w->chand, w->on_complete);
+    if (found) {
+      GPR_ASSERT(found->on_complete == w->on_complete);
+      grpc_connectivity_state_notify_on_state_change(
+          exec_ctx, &found->chand->state_tracker, NULL, &found->my_closure);
+    }
+    grpc_polling_entity_del_from_pollset_set(exec_ctx, &w->pollent,
+                                             w->chand->interested_parties);
+    GRPC_CHANNEL_STACK_UNREF(exec_ctx, w->chand->owning_stack,
+                             "external_connectivity_watcher");
+    gpr_free(w);
+  }
 }
 
 void grpc_client_channel_watch_connectivity_state(
-    grpc_exec_ctx *exec_ctx, grpc_channel_element *elem, grpc_pollset *pollset,
-    grpc_connectivity_state *state, grpc_closure *closure) {
+    grpc_exec_ctx *exec_ctx, grpc_channel_element *elem,
+    grpc_polling_entity pollent, grpc_connectivity_state *state,
+    grpc_closure *closure, grpc_closure *watcher_timer_init) {
   channel_data *chand = elem->channel_data;
-  external_connectivity_watcher *w = gpr_malloc(sizeof(*w));
+  external_connectivity_watcher *w = gpr_zalloc(sizeof(*w));
   w->chand = chand;
-  w->pollset = pollset;
+  w->pollent = pollent;
   w->on_complete = closure;
   w->state = state;
-  grpc_pollset_set_add_pollset(exec_ctx, chand->interested_parties, pollset);
+  w->watcher_timer_init = watcher_timer_init;
+  grpc_polling_entity_add_to_pollset_set(exec_ctx, &w->pollent,
+                                         chand->interested_parties);
   GRPC_CHANNEL_STACK_REF(w->chand->owning_stack,
                          "external_connectivity_watcher");
-  grpc_closure_sched(
+  GRPC_CLOSURE_SCHED(
       exec_ctx,
-      grpc_closure_init(&w->my_closure, watch_connectivity_state_locked, w,
-                        grpc_combiner_scheduler(chand->combiner, true)),
+      GRPC_CLOSURE_INIT(&w->my_closure, watch_connectivity_state_locked, w,
+                        grpc_combiner_scheduler(chand->combiner)),
       GRPC_ERROR_NONE);
 }
diff --git a/src/core/ext/filters/client_channel/client_channel.h b/src/core/ext/filters/client_channel/client_channel.h
index 8d2490ea55..c99f0092e9 100644
--- a/src/core/ext/filters/client_channel/client_channel.h
+++ b/src/core/ext/filters/client_channel/client_channel.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -38,6 +23,8 @@
 #include "src/core/ext/filters/client_channel/resolver.h"
 #include "src/core/lib/channel/channel_stack.h"
 
+extern grpc_tracer_flag grpc_client_channel_trace;
+
 // Channel arg key for server URI string.
 #define GRPC_ARG_SERVER_URI "grpc.server_uri"
 
@@ -53,9 +40,13 @@ extern const grpc_channel_filter grpc_client_channel_filter;
 grpc_connectivity_state grpc_client_channel_check_connectivity_state(
     grpc_exec_ctx *exec_ctx, grpc_channel_element *elem, int try_to_connect);
 
+int grpc_client_channel_num_external_connectivity_watchers(
+    grpc_channel_element *elem);
+
 void grpc_client_channel_watch_connectivity_state(
-    grpc_exec_ctx *exec_ctx, grpc_channel_element *elem, grpc_pollset *pollset,
-    grpc_connectivity_state *state, grpc_closure *on_complete);
+    grpc_exec_ctx *exec_ctx, grpc_channel_element *elem,
+    grpc_polling_entity pollent, grpc_connectivity_state *state,
+    grpc_closure *on_complete, grpc_closure *watcher_timer_init);
 
 /* Debug helper: pull the subchannel call from a call stack element */
 grpc_subchannel_call *grpc_client_channel_get_subchannel_call(
diff --git a/src/core/ext/filters/client_channel/client_channel_factory.c b/src/core/ext/filters/client_channel/client_channel_factory.c
index 44e83b54b5..7220a8639e 100644
--- a/src/core/ext/filters/client_channel/client_channel_factory.c
+++ b/src/core/ext/filters/client_channel/client_channel_factory.c
@@ -1,37 +1,23 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
 #include "src/core/ext/filters/client_channel/client_channel_factory.h"
+#include "src/core/lib/channel/channel_args.h"
 
 void grpc_client_channel_factory_ref(grpc_client_channel_factory* factory) {
   factory->vtable->ref(factory);
@@ -78,10 +64,6 @@ static const grpc_arg_pointer_vtable factory_arg_vtable = {
 
 grpc_arg grpc_client_channel_factory_create_channel_arg(
     grpc_client_channel_factory* factory) {
-  grpc_arg arg;
-  arg.type = GRPC_ARG_POINTER;
-  arg.key = GRPC_ARG_CLIENT_CHANNEL_FACTORY;
-  arg.value.pointer.p = factory;
-  arg.value.pointer.vtable = &factory_arg_vtable;
-  return arg;
+  return grpc_channel_arg_pointer_create(GRPC_ARG_CLIENT_CHANNEL_FACTORY,
+                                         factory, &factory_arg_vtable);
 }
diff --git a/src/core/ext/filters/client_channel/client_channel_factory.h b/src/core/ext/filters/client_channel/client_channel_factory.h
index 2355588f18..ce6266c769 100644
--- a/src/core/ext/filters/client_channel/client_channel_factory.h
+++ b/src/core/ext/filters/client_channel/client_channel_factory.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/filters/client_channel/client_channel_plugin.c b/src/core/ext/filters/client_channel/client_channel_plugin.c
index 0e3eae6615..c32e83d012 100644
--- a/src/core/ext/filters/client_channel/client_channel_plugin.c
+++ b/src/core/ext/filters/client_channel/client_channel_plugin.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -69,10 +54,8 @@ static bool set_default_host_if_unset(grpc_exec_ctx *exec_ctx,
   char *default_authority = grpc_get_default_authority(
       exec_ctx, grpc_channel_stack_builder_get_target(builder));
   if (default_authority != NULL) {
-    grpc_arg arg;
-    arg.type = GRPC_ARG_STRING;
-    arg.key = GRPC_ARG_DEFAULT_AUTHORITY;
-    arg.value.string = default_authority;
+    grpc_arg arg = grpc_channel_arg_string_create(GRPC_ARG_DEFAULT_AUTHORITY,
+                                                  default_authority);
     grpc_channel_args *new_args = grpc_channel_args_copy_and_add(args, &arg, 1);
     grpc_channel_stack_builder_set_channel_arguments(exec_ctx, builder,
                                                      new_args);
@@ -95,6 +78,10 @@ void grpc_client_channel_init(void) {
       GRPC_CLIENT_CHANNEL, GRPC_CHANNEL_INIT_BUILTIN_PRIORITY, append_filter,
       (void *)&grpc_client_channel_filter);
   grpc_http_connect_register_handshaker_factory();
+  grpc_register_tracer(&grpc_client_channel_trace);
+#ifndef NDEBUG
+  grpc_register_tracer(&grpc_trace_resolver_refcount);
+#endif
 }
 
 void grpc_client_channel_shutdown(void) {
diff --git a/src/core/ext/filters/client_channel/connector.c b/src/core/ext/filters/client_channel/connector.c
index 51c1d7ece7..c258468e58 100644
--- a/src/core/ext/filters/client_channel/connector.c
+++ b/src/core/ext/filters/client_channel/connector.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/filters/client_channel/connector.h b/src/core/ext/filters/client_channel/connector.h
index 23040c3e23..7f3d4a1cc0 100644
--- a/src/core/ext/filters/client_channel/connector.h
+++ b/src/core/ext/filters/client_channel/connector.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/filters/client_channel/http_connect_handshaker.c b/src/core/ext/filters/client_channel/http_connect_handshaker.c
index c09a863d00..0952dc6d4e 100644
--- a/src/core/ext/filters/client_channel/http_connect_handshaker.c
+++ b/src/core/ext/filters/client_channel/http_connect_handshaker.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -133,7 +118,7 @@ static void handshake_failed_locked(grpc_exec_ctx* exec_ctx,
     handshaker->shutdown = true;
   }
   // Invoke callback.
-  grpc_closure_sched(exec_ctx, handshaker->on_handshake_done, error);
+  GRPC_CLOSURE_SCHED(exec_ctx, handshaker->on_handshake_done, error);
 }
 
 // Callback invoked when finished writing HTTP CONNECT request.
@@ -232,7 +217,7 @@ static void on_read_done(grpc_exec_ctx* exec_ctx, void* arg,
     goto done;
   }
   // Success.  Invoke handshake-done callback.
-  grpc_closure_sched(exec_ctx, handshaker->on_handshake_done, error);
+  GRPC_CLOSURE_SCHED(exec_ctx, handshaker->on_handshake_done, error);
 done:
   // Set shutdown to true so that subsequent calls to
   // http_connect_handshaker_shutdown() do nothing.
@@ -281,7 +266,7 @@ static void http_connect_handshaker_do_handshake(
     gpr_mu_lock(&handshaker->mu);
     handshaker->shutdown = true;
     gpr_mu_unlock(&handshaker->mu);
-    grpc_closure_sched(exec_ctx, on_handshake_done, GRPC_ERROR_NONE);
+    GRPC_CLOSURE_SCHED(exec_ctx, on_handshake_done, GRPC_ERROR_NONE);
     return;
   }
   GPR_ASSERT(arg->type == GRPC_ARG_STRING);
@@ -354,9 +339,9 @@ static grpc_handshaker* grpc_http_connect_handshaker_create() {
   gpr_mu_init(&handshaker->mu);
   gpr_ref_init(&handshaker->refcount, 1);
   grpc_slice_buffer_init(&handshaker->write_buffer);
-  grpc_closure_init(&handshaker->request_done_closure, on_write_done,
+  GRPC_CLOSURE_INIT(&handshaker->request_done_closure, on_write_done,
                     handshaker, grpc_schedule_on_exec_ctx);
-  grpc_closure_init(&handshaker->response_read_closure, on_read_done,
+  GRPC_CLOSURE_INIT(&handshaker->response_read_closure, on_read_done,
                     handshaker, grpc_schedule_on_exec_ctx);
   grpc_http_parser_init(&handshaker->http_parser, GRPC_HTTP_RESPONSE,
                         &handshaker->http_response);
diff --git a/src/core/ext/filters/client_channel/http_connect_handshaker.h b/src/core/ext/filters/client_channel/http_connect_handshaker.h
index 6d7c204d71..928a23dc93 100644
--- a/src/core/ext/filters/client_channel/http_connect_handshaker.h
+++ b/src/core/ext/filters/client_channel/http_connect_handshaker.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/filters/client_channel/http_proxy.c b/src/core/ext/filters/client_channel/http_proxy.c
index f8a2d06b8a..cfb5ec6f00 100644
--- a/src/core/ext/filters/client_channel/http_proxy.c
+++ b/src/core/ext/filters/client_channel/http_proxy.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -95,10 +80,9 @@ static bool proxy_mapper_map_name(grpc_exec_ctx* exec_ctx,
     grpc_uri_destroy(uri);
     return false;
   }
-  grpc_arg new_arg;
-  new_arg.key = GRPC_ARG_HTTP_CONNECT_SERVER;
-  new_arg.type = GRPC_ARG_STRING;
-  new_arg.value.string = uri->path[0] == '/' ? uri->path + 1 : uri->path;
+  grpc_arg new_arg = grpc_channel_arg_string_create(
+      GRPC_ARG_HTTP_CONNECT_SERVER,
+      uri->path[0] == '/' ? uri->path + 1 : uri->path);
   *new_args = grpc_channel_args_copy_and_add(args, &new_arg, 1);
   grpc_uri_destroy(uri);
   return true;
diff --git a/src/core/ext/filters/client_channel/http_proxy.h b/src/core/ext/filters/client_channel/http_proxy.h
index f0df74bbda..34694931d0 100644
--- a/src/core/ext/filters/client_channel/http_proxy.h
+++ b/src/core/ext/filters/client_channel/http_proxy.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/filters/client_channel/lb_policy.c b/src/core/ext/filters/client_channel/lb_policy.c
index 112ba40658..10b032214b 100644
--- a/src/core/ext/filters/client_channel/lb_policy.c
+++ b/src/core/ext/filters/client_channel/lb_policy.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -36,6 +21,11 @@
 
 #define WEAK_REF_BITS 16
 
+#ifndef NDEBUG
+grpc_tracer_flag grpc_trace_lb_policy_refcount =
+    GRPC_TRACER_INITIALIZER(false, "lb_policy_refcount");
+#endif
+
 void grpc_lb_policy_init(grpc_lb_policy *policy,
                          const grpc_lb_policy_vtable *vtable,
                          grpc_combiner *combiner) {
@@ -45,7 +35,7 @@ void grpc_lb_policy_init(grpc_lb_policy *policy,
   policy->combiner = GRPC_COMBINER_REF(combiner, "lb_policy");
 }
 
-#ifdef GRPC_LB_POLICY_REFCOUNT_DEBUG
+#ifndef NDEBUG
 #define REF_FUNC_EXTRA_ARGS , const char *file, int line, const char *reason
 #define REF_MUTATE_EXTRA_ARGS REF_FUNC_EXTRA_ARGS, const char *purpose
 #define REF_FUNC_PASS_ARGS(new_reason) , file, line, new_reason
@@ -61,11 +51,12 @@ static gpr_atm ref_mutate(grpc_lb_policy *c, gpr_atm delta,
                           int barrier REF_MUTATE_EXTRA_ARGS) {
   gpr_atm old_val = barrier ? gpr_atm_full_fetch_add(&c->ref_pair, delta)
                             : gpr_atm_no_barrier_fetch_add(&c->ref_pair, delta);
-#ifdef GRPC_LB_POLICY_REFCOUNT_DEBUG
-  gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
-          "LB_POLICY: 0x%" PRIxPTR " %12s 0x%" PRIxPTR " -> 0x%" PRIxPTR
-          " [%s]",
-          (intptr_t)c, purpose, old_val, old_val + delta, reason);
+#ifndef NDEBUG
+  if (GRPC_TRACER_ON(grpc_trace_lb_policy_refcount)) {
+    gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
+            "LB_POLICY: 0x%p %12s 0x%" PRIxPTR " -> 0x%" PRIxPTR " [%s]", c,
+            purpose, old_val, old_val + delta, reason);
+  }
 #endif
   return old_val;
 }
@@ -89,11 +80,10 @@ void grpc_lb_policy_unref(grpc_exec_ctx *exec_ctx,
   gpr_atm mask = ~(gpr_atm)((1 << WEAK_REF_BITS) - 1);
   gpr_atm check = 1 << WEAK_REF_BITS;
   if ((old_val & mask) == check) {
-    grpc_closure_sched(
-        exec_ctx,
-        grpc_closure_create(shutdown_locked, policy,
-                            grpc_combiner_scheduler(policy->combiner, false)),
-        GRPC_ERROR_NONE);
+    GRPC_CLOSURE_SCHED(exec_ctx, GRPC_CLOSURE_CREATE(
+                                     shutdown_locked, policy,
+                                     grpc_combiner_scheduler(policy->combiner)),
+                       GRPC_ERROR_NONE);
   } else {
     grpc_lb_policy_weak_unref(exec_ctx,
                               policy REF_FUNC_PASS_ARGS("strong-unref"));
@@ -166,3 +156,9 @@ grpc_connectivity_state grpc_lb_policy_check_connectivity_locked(
   return policy->vtable->check_connectivity_locked(exec_ctx, policy,
                                                    connectivity_error);
 }
+
+void grpc_lb_policy_update_locked(grpc_exec_ctx *exec_ctx,
+                                  grpc_lb_policy *policy,
+                                  const grpc_lb_policy_args *lb_policy_args) {
+  policy->vtable->update_locked(exec_ctx, policy, lb_policy_args);
+}
diff --git a/src/core/ext/filters/client_channel/lb_policy.h b/src/core/ext/filters/client_channel/lb_policy.h
index 184b2ef720..645d51e138 100644
--- a/src/core/ext/filters/client_channel/lb_policy.h
+++ b/src/core/ext/filters/client_channel/lb_policy.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -42,6 +27,11 @@
     is expected to be extended to contain some parameters) */
 typedef struct grpc_lb_policy grpc_lb_policy;
 typedef struct grpc_lb_policy_vtable grpc_lb_policy_vtable;
+typedef struct grpc_lb_policy_args grpc_lb_policy_args;
+
+#ifndef NDEBUG
+extern grpc_tracer_flag grpc_trace_lb_policy_refcount;
+#endif
 
 struct grpc_lb_policy {
   const grpc_lb_policy_vtable *vtable;
@@ -105,10 +95,12 @@ struct grpc_lb_policy_vtable {
                                         grpc_lb_policy *policy,
                                         grpc_connectivity_state *state,
                                         grpc_closure *closure);
+
+  void (*update_locked)(grpc_exec_ctx *exec_ctx, grpc_lb_policy *policy,
+                        const grpc_lb_policy_args *args);
 };
 
-/*#define GRPC_LB_POLICY_REFCOUNT_DEBUG*/
-#ifdef GRPC_LB_POLICY_REFCOUNT_DEBUG
+#ifndef NDEBUG
 
 /* Strong references: the policy will shutdown when they reach zero */
 #define GRPC_LB_POLICY_REF(p, r) \
@@ -149,7 +141,9 @@ void grpc_lb_policy_init(grpc_lb_policy *policy,
 
 /** Finds an appropriate subchannel for a call, based on \a pick_args.
 
-    \a target will be set to the selected subchannel, or NULL on failure.
+    \a target will be set to the selected subchannel, or NULL on failure
+    or when the LB policy decides to drop the call.
+
     Upon success, \a user_data will be set to whatever opaque information
     may need to be propagated from the LB policy, or NULL if not needed.
     \a context will be populated with context to pass to the subchannel
@@ -205,4 +199,9 @@ grpc_connectivity_state grpc_lb_policy_check_connectivity_locked(
     grpc_exec_ctx *exec_ctx, grpc_lb_policy *policy,
     grpc_error **connectivity_error);
 
+/** Update \a policy with \a lb_policy_args. */
+void grpc_lb_policy_update_locked(grpc_exec_ctx *exec_ctx,
+                                  grpc_lb_policy *policy,
+                                  const grpc_lb_policy_args *lb_policy_args);
+
 #endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_LB_POLICY_H */
diff --git a/src/core/ext/filters/client_channel/lb_policy/grpclb/client_load_reporting_filter.c b/src/core/ext/filters/client_channel/lb_policy/grpclb/client_load_reporting_filter.c
index 67baa46de7..52c6e38c87 100644
--- a/src/core/ext/filters/client_channel/lb_policy/grpclb/client_load_reporting_filter.c
+++ b/src/core/ext/filters/client_channel/lb_policy/grpclb/client_load_reporting_filter.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2017, Google Inc.
- * All rights reserved.
+ * Copyright 2017 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -68,7 +53,7 @@ static void on_complete_for_send(grpc_exec_ctx *exec_ctx, void *arg,
   if (error == GRPC_ERROR_NONE) {
     calld->send_initial_metadata_succeeded = true;
   }
-  grpc_closure_run(exec_ctx, calld->original_on_complete_for_send,
+  GRPC_CLOSURE_RUN(exec_ctx, calld->original_on_complete_for_send,
                    GRPC_ERROR_REF(error));
 }
 
@@ -78,7 +63,7 @@ static void recv_initial_metadata_ready(grpc_exec_ctx *exec_ctx, void *arg,
   if (error == GRPC_ERROR_NONE) {
     calld->recv_initial_metadata_succeeded = true;
   }
-  grpc_closure_run(exec_ctx, calld->original_recv_initial_metadata_ready,
+  GRPC_CLOSURE_RUN(exec_ctx, calld->original_recv_initial_metadata_ready,
                    GRPC_ERROR_REF(error));
 }
 
@@ -119,7 +104,7 @@ static void start_transport_stream_op_batch(
   // Intercept send_initial_metadata.
   if (batch->send_initial_metadata) {
     calld->original_on_complete_for_send = batch->on_complete;
-    grpc_closure_init(&calld->on_complete_for_send, on_complete_for_send, calld,
+    GRPC_CLOSURE_INIT(&calld->on_complete_for_send, on_complete_for_send, calld,
                       grpc_schedule_on_exec_ctx);
     batch->on_complete = &calld->on_complete_for_send;
   }
@@ -127,7 +112,7 @@ static void start_transport_stream_op_batch(
   if (batch->recv_initial_metadata) {
     calld->original_recv_initial_metadata_ready =
         batch->payload->recv_initial_metadata.recv_initial_metadata_ready;
-    grpc_closure_init(&calld->recv_initial_metadata_ready,
+    GRPC_CLOSURE_INIT(&calld->recv_initial_metadata_ready,
                       recv_initial_metadata_ready, calld,
                       grpc_schedule_on_exec_ctx);
     batch->payload->recv_initial_metadata.recv_initial_metadata_ready =
diff --git a/src/core/ext/filters/client_channel/lb_policy/grpclb/client_load_reporting_filter.h b/src/core/ext/filters/client_channel/lb_policy/grpclb/client_load_reporting_filter.h
index 28b313d874..51e30b20b8 100644
--- a/src/core/ext/filters/client_channel/lb_policy/grpclb/client_load_reporting_filter.h
+++ b/src/core/ext/filters/client_channel/lb_policy/grpclb/client_load_reporting_filter.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2017, Google Inc.
- * All rights reserved.
+ * Copyright 2017 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.c b/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.c
index b7c0e929b7..cccc3e871a 100644
--- a/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.c
+++ b/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -115,6 +100,7 @@
 #include "src/core/ext/filters/client_channel/lb_policy_factory.h"
 #include "src/core/ext/filters/client_channel/lb_policy_registry.h"
 #include "src/core/ext/filters/client_channel/parse_address.h"
+#include "src/core/ext/filters/client_channel/resolver/fake/fake_resolver.h"
 #include "src/core/lib/channel/channel_args.h"
 #include "src/core/lib/channel/channel_stack.h"
 #include "src/core/lib/iomgr/combiner.h"
@@ -137,7 +123,7 @@
 #define GRPC_GRPCLB_RECONNECT_MAX_BACKOFF_SECONDS 120
 #define GRPC_GRPCLB_RECONNECT_JITTER 0.2
 
-grpc_tracer_flag grpc_lb_glb_trace = GRPC_TRACER_INITIALIZER(false);
+grpc_tracer_flag grpc_lb_glb_trace = GRPC_TRACER_INITIALIZER(false, "glb");
 
 /* add lb_token of selected subchannel (address) to the call's initial
  * metadata */
@@ -198,7 +184,7 @@ static void wrapped_rr_closure(grpc_exec_ctx *exec_ctx, void *arg,
   wrapped_rr_closure_arg *wc_arg = arg;
 
   GPR_ASSERT(wc_arg->wrapped_closure != NULL);
-  grpc_closure_sched(exec_ctx, wc_arg->wrapped_closure, GRPC_ERROR_REF(error));
+  GRPC_CLOSURE_SCHED(exec_ctx, wc_arg->wrapped_closure, GRPC_ERROR_REF(error));
 
   if (wc_arg->rr_policy != NULL) {
     /* if *target is NULL, no pick has been made by the RR policy (eg, all
@@ -270,7 +256,7 @@ static void add_pending_pick(pending_pick **root,
   pp->wrapped_on_complete_arg.lb_token_mdelem_storage =
       pick_args->lb_token_mdelem_storage;
   pp->wrapped_on_complete_arg.free_when_done = pp;
-  grpc_closure_init(&pp->wrapped_on_complete_arg.wrapper_closure,
+  GRPC_CLOSURE_INIT(&pp->wrapped_on_complete_arg.wrapper_closure,
                     wrapped_rr_closure, &pp->wrapped_on_complete_arg,
                     grpc_schedule_on_exec_ctx);
   *root = pp;
@@ -289,7 +275,7 @@ static void add_pending_ping(pending_ping **root, grpc_closure *notify) {
   pping->wrapped_notify_arg.wrapped_closure = notify;
   pping->wrapped_notify_arg.free_when_done = pping;
   pping->next = *root;
-  grpc_closure_init(&pping->wrapped_notify_arg.wrapper_closure,
+  GRPC_CLOSURE_INIT(&pping->wrapped_notify_arg.wrapper_closure,
                     wrapped_rr_closure, &pping->wrapped_notify_arg,
                     grpc_schedule_on_exec_ctx);
   *root = pping;
@@ -315,6 +301,9 @@ typedef struct glb_lb_policy {
   /** for communicating with the LB server */
   grpc_channel *lb_channel;
 
+  /** response generator to inject address updates into \a lb_channel */
+  grpc_fake_resolver_response_generator *response_generator;
+
   /** the RR policy to use of the backend servers returned by the LB server */
   grpc_lb_policy *rr_policy;
 
@@ -323,10 +312,18 @@ typedef struct glb_lb_policy {
   /** our connectivity state tracker */
   grpc_connectivity_state_tracker state_tracker;
 
+  /** connectivity state of the LB channel */
+  grpc_connectivity_state lb_channel_connectivity;
+
   /** stores the deserialized response from the LB. May be NULL until one such
    * response has arrived. */
   grpc_grpclb_serverlist *serverlist;
 
+  /** Index into serverlist for next pick.
+   * If the server at this index is a drop, we return a drop.
+   * Otherwise, we delegate to the RR policy. */
+  size_t serverlist_index;
+
   /** list of picks that are waiting on RR's policy connectivity */
   pending_pick *pending_picks;
 
@@ -335,10 +332,27 @@ typedef struct glb_lb_policy {
 
   bool shutting_down;
 
+  /** are we currently updating lb_call? */
+  bool updating_lb_call;
+
+  /** are we currently updating lb_channel? */
+  bool updating_lb_channel;
+
+  /** are we already watching the LB channel's connectivity? */
+  bool watching_lb_channel;
+
+  /** is \a lb_call_retry_timer active? */
+  bool retry_timer_active;
+
+  /** called upon changes to the LB channel's connectivity. */
+  grpc_closure lb_channel_on_connectivity_changed;
+
+  /** args from the latest update received while already updating, or NULL */
+  grpc_lb_policy_args *pending_update_args;
+
   /************************************************************/
   /*  client data associated with the LB server communication */
   /************************************************************/
-
   /* Finished sending initial request. */
   grpc_closure lb_on_sent_initial_request;
 
@@ -402,6 +416,9 @@ struct rr_connectivity_data {
 
 static bool is_server_valid(const grpc_grpclb_server *server, size_t idx,
                             bool log) {
+  if (server->drop_for_rate_limiting || server->drop_for_load_balancing) {
+    return false;
+  }
   const grpc_grpclb_ip_address *ip = &server->ip_address;
   if (server->port >> 16 != 0) {
     if (log) {
@@ -411,7 +428,6 @@ static bool is_server_valid(const grpc_grpclb_server *server, size_t idx,
     }
     return false;
   }
-
   if (ip->size != 4 && ip->size != 16) {
     if (log) {
       gpr_log(GPR_ERROR,
@@ -445,11 +461,12 @@ static const grpc_lb_user_data_vtable lb_token_vtable = {
 
 static void parse_server(const grpc_grpclb_server *server,
                          grpc_resolved_address *addr) {
+  memset(addr, 0, sizeof(*addr));
+  if (server->drop_for_rate_limiting || server->drop_for_load_balancing) return;
   const uint16_t netorder_port = htons((uint16_t)server->port);
   /* the addresses are given in binary format (a in(6)_addr struct) in
    * server->ip_address.bytes. */
   const grpc_grpclb_ip_address *ip = &server->ip_address;
-  memset(addr, 0, sizeof(*addr));
   if (ip->size == 4) {
     addr->len = sizeof(struct sockaddr_in);
     struct sockaddr_in *addr4 = (struct sockaddr_in *)&addr->addr;
@@ -525,10 +542,9 @@ static grpc_lb_addresses *process_serverlist_locked(
   return lb_addresses;
 }
 
-/* returns true if the new RR policy should replace the current one, if any */
-static bool update_lb_connectivity_status_locked(
+static void update_lb_connectivity_status_locked(
     grpc_exec_ctx *exec_ctx, glb_lb_policy *glb_policy,
-    grpc_connectivity_state new_rr_state, grpc_error *new_rr_state_error) {
+    grpc_connectivity_state rr_state, grpc_error *rr_state_error) {
   const grpc_connectivity_state curr_glb_state =
       grpc_connectivity_state_check(&glb_policy->state_tracker);
 
@@ -562,40 +578,73 @@ static bool update_lb_connectivity_status_locked(
    *  (*) This function mustn't be called during shutting down. */
   GPR_ASSERT(curr_glb_state != GRPC_CHANNEL_SHUTDOWN);
 
-  switch (new_rr_state) {
+  switch (rr_state) {
     case GRPC_CHANNEL_TRANSIENT_FAILURE:
     case GRPC_CHANNEL_SHUTDOWN:
-      GPR_ASSERT(new_rr_state_error != GRPC_ERROR_NONE);
-      return false; /* don't replace the RR policy */
+      GPR_ASSERT(rr_state_error != GRPC_ERROR_NONE);
+      break;
     case GRPC_CHANNEL_INIT:
     case GRPC_CHANNEL_IDLE:
     case GRPC_CHANNEL_CONNECTING:
     case GRPC_CHANNEL_READY:
-      GPR_ASSERT(new_rr_state_error == GRPC_ERROR_NONE);
+      GPR_ASSERT(rr_state_error == GRPC_ERROR_NONE);
   }
 
   if (GRPC_TRACER_ON(grpc_lb_glb_trace)) {
-    gpr_log(GPR_INFO,
-            "Setting grpclb's state to %s from new RR policy %p state.",
-            grpc_connectivity_state_name(new_rr_state),
-            (void *)glb_policy->rr_policy);
+    gpr_log(
+        GPR_INFO, "Setting grpclb's state to %s from new RR policy %p state.",
+        grpc_connectivity_state_name(rr_state), (void *)glb_policy->rr_policy);
   }
-  grpc_connectivity_state_set(exec_ctx, &glb_policy->state_tracker,
-                              new_rr_state, GRPC_ERROR_REF(new_rr_state_error),
+  grpc_connectivity_state_set(exec_ctx, &glb_policy->state_tracker, rr_state,
+                              GRPC_ERROR_REF(rr_state_error),
                               "update_lb_connectivity_status_locked");
-  return true;
 }
 
-/* perform a pick over \a rr_policy. Given that a pick can return immediately
- * (ignoring its completion callback) we need to perform the cleanups this
- * callback would be otherwise resposible for */
+/* Perform a pick over \a glb_policy->rr_policy. Given that a pick can return
+ * immediately (ignoring its completion callback), we need to perform the
+ * cleanups this callback would otherwise be resposible for.
+ * If \a force_async is true, then we will manually schedule the
+ * completion callback even if the pick is available immediately. */
 static bool pick_from_internal_rr_locked(
-    grpc_exec_ctx *exec_ctx, grpc_lb_policy *rr_policy,
-    const grpc_lb_policy_pick_args *pick_args,
+    grpc_exec_ctx *exec_ctx, glb_lb_policy *glb_policy,
+    const grpc_lb_policy_pick_args *pick_args, bool force_async,
     grpc_connected_subchannel **target, wrapped_rr_closure_arg *wc_arg) {
-  GPR_ASSERT(rr_policy != NULL);
+  // Look at the index into the serverlist to see if we should drop this call.
+  grpc_grpclb_server *server =
+      glb_policy->serverlist->servers[glb_policy->serverlist_index++];
+  if (glb_policy->serverlist_index == glb_policy->serverlist->num_servers) {
+    glb_policy->serverlist_index = 0;  // Wrap-around.
+  }
+  if (server->drop_for_rate_limiting || server->drop_for_load_balancing) {
+    // Not using the RR policy, so unref it.
+    if (GRPC_TRACER_ON(grpc_lb_glb_trace)) {
+      gpr_log(GPR_INFO, "Unreffing RR for drop (0x%" PRIxPTR ")",
+              (intptr_t)wc_arg->rr_policy);
+    }
+    GRPC_LB_POLICY_UNREF(exec_ctx, wc_arg->rr_policy, "glb_pick_sync");
+    // Update client load reporting stats to indicate the number of
+    // dropped calls.  Note that we have to do this here instead of in
+    // the client_load_reporting filter, because we do not create a
+    // subchannel call (and therefore no client_load_reporting filter)
+    // for dropped calls.
+    grpc_grpclb_client_stats_add_call_started(wc_arg->client_stats);
+    grpc_grpclb_client_stats_add_call_finished(
+        server->drop_for_rate_limiting, server->drop_for_load_balancing,
+        false /* failed_to_send */, false /* known_received */,
+        wc_arg->client_stats);
+    grpc_grpclb_client_stats_unref(wc_arg->client_stats);
+    if (force_async) {
+      GPR_ASSERT(wc_arg->wrapped_closure != NULL);
+      GRPC_CLOSURE_SCHED(exec_ctx, wc_arg->wrapped_closure, GRPC_ERROR_NONE);
+      gpr_free(wc_arg->free_when_done);
+      return false;
+    }
+    gpr_free(wc_arg->free_when_done);
+    return true;
+  }
+  // Pick via the RR policy.
   const bool pick_done = grpc_lb_policy_pick_locked(
-      exec_ctx, rr_policy, pick_args, target, wc_arg->context,
+      exec_ctx, wc_arg->rr_policy, pick_args, target, wc_arg->context,
       (void **)&wc_arg->lb_token, &wc_arg->wrapper_closure);
   if (pick_done) {
     /* synchronous grpc_lb_policy_pick call. Unref the RR policy. */
@@ -604,17 +653,20 @@ static bool pick_from_internal_rr_locked(
               (intptr_t)wc_arg->rr_policy);
     }
     GRPC_LB_POLICY_UNREF(exec_ctx, wc_arg->rr_policy, "glb_pick_sync");
-
     /* add the load reporting initial metadata */
     initial_metadata_add_lb_token(exec_ctx, pick_args->initial_metadata,
                                   pick_args->lb_token_mdelem_storage,
                                   GRPC_MDELEM_REF(wc_arg->lb_token));
-
     // Pass on client stats via context. Passes ownership of the reference.
     GPR_ASSERT(wc_arg->client_stats != NULL);
     wc_arg->context[GRPC_GRPCLB_CLIENT_STATS].value = wc_arg->client_stats;
     wc_arg->context[GRPC_GRPCLB_CLIENT_STATS].destroy = destroy_client_stats;
-
+    if (force_async) {
+      GPR_ASSERT(wc_arg->wrapped_closure != NULL);
+      GRPC_CLOSURE_SCHED(exec_ctx, wc_arg->wrapped_closure, GRPC_ERROR_NONE);
+      gpr_free(wc_arg->free_when_done);
+      return false;
+    }
     gpr_free(wc_arg->free_when_done);
   }
   /* else, the pending pick will be registered and taken care of by the
@@ -624,45 +676,38 @@ static bool pick_from_internal_rr_locked(
   return pick_done;
 }
 
-static grpc_lb_policy *create_rr_locked(
-    grpc_exec_ctx *exec_ctx, const grpc_grpclb_serverlist *serverlist,
-    glb_lb_policy *glb_policy) {
-  GPR_ASSERT(serverlist != NULL && serverlist->num_servers > 0);
-
-  grpc_lb_policy_args args;
-  memset(&args, 0, sizeof(args));
-  args.client_channel_factory = glb_policy->cc_factory;
-  args.combiner = glb_policy->base.combiner;
+static grpc_lb_policy_args *lb_policy_args_create(grpc_exec_ctx *exec_ctx,
+                                                  glb_lb_policy *glb_policy) {
+  grpc_lb_policy_args *args = gpr_zalloc(sizeof(*args));
+  args->client_channel_factory = glb_policy->cc_factory;
+  args->combiner = glb_policy->base.combiner;
   grpc_lb_addresses *addresses =
-      process_serverlist_locked(exec_ctx, serverlist);
-
+      process_serverlist_locked(exec_ctx, glb_policy->serverlist);
   // Replace the LB addresses in the channel args that we pass down to
   // the subchannel.
   static const char *keys_to_remove[] = {GRPC_ARG_LB_ADDRESSES};
   const grpc_arg arg = grpc_lb_addresses_create_channel_arg(addresses);
-  args.args = grpc_channel_args_copy_and_add_and_remove(
+  args->args = grpc_channel_args_copy_and_add_and_remove(
       glb_policy->args, keys_to_remove, GPR_ARRAY_SIZE(keys_to_remove), &arg,
       1);
-
-  grpc_lb_policy *rr = grpc_lb_policy_create(exec_ctx, "round_robin", &args);
-  GPR_ASSERT(rr != NULL);
   grpc_lb_addresses_destroy(exec_ctx, addresses);
-  grpc_channel_args_destroy(exec_ctx, args.args);
-  return rr;
+  return args;
+}
+
+static void lb_policy_args_destroy(grpc_exec_ctx *exec_ctx,
+                                   grpc_lb_policy_args *args) {
+  grpc_channel_args_destroy(exec_ctx, args->args);
+  gpr_free(args);
 }
 
 static void glb_rr_connectivity_changed_locked(grpc_exec_ctx *exec_ctx,
                                                void *arg, grpc_error *error);
-/* glb_policy->rr_policy may be NULL (initial handover) */
-static void rr_handover_locked(grpc_exec_ctx *exec_ctx,
-                               glb_lb_policy *glb_policy) {
-  GPR_ASSERT(glb_policy->serverlist != NULL &&
-             glb_policy->serverlist->num_servers > 0);
-
-  if (glb_policy->shutting_down) return;
+static void create_rr_locked(grpc_exec_ctx *exec_ctx, glb_lb_policy *glb_policy,
+                             grpc_lb_policy_args *args) {
+  GPR_ASSERT(glb_policy->rr_policy == NULL);
 
   grpc_lb_policy *new_rr_policy =
-      create_rr_locked(exec_ctx, glb_policy->serverlist, glb_policy);
+      grpc_lb_policy_create(exec_ctx, "round_robin", args);
   if (new_rr_policy == NULL) {
     gpr_log(GPR_ERROR,
             "Failure creating a RoundRobin policy for serverlist update with "
@@ -673,41 +718,16 @@ static void rr_handover_locked(grpc_exec_ctx *exec_ctx,
             (void *)glb_policy->rr_policy);
     return;
   }
-
-  grpc_error *new_rr_state_error = NULL;
-  const grpc_connectivity_state new_rr_state =
-      grpc_lb_policy_check_connectivity_locked(exec_ctx, new_rr_policy,
-                                               &new_rr_state_error);
-  /* Connectivity state is a function of the new RR policy just created */
-  const bool replace_old_rr = update_lb_connectivity_status_locked(
-      exec_ctx, glb_policy, new_rr_state, new_rr_state_error);
-
-  if (!replace_old_rr) {
-    /* dispose of the new RR policy that won't be used after all */
-    GRPC_LB_POLICY_UNREF(exec_ctx, new_rr_policy, "rr_handover_no_replace");
-    if (GRPC_TRACER_ON(grpc_lb_glb_trace)) {
-      gpr_log(GPR_INFO,
-              "Keeping old RR policy (%p) despite new serverlist: new RR "
-              "policy was in %s connectivity state.",
-              (void *)glb_policy->rr_policy,
-              grpc_connectivity_state_name(new_rr_state));
-    }
-    return;
-  }
-
-  if (GRPC_TRACER_ON(grpc_lb_glb_trace)) {
-    gpr_log(GPR_INFO, "Created RR policy (%p) to replace old RR (%p)",
-            (void *)new_rr_policy, (void *)glb_policy->rr_policy);
-  }
-
-  if (glb_policy->rr_policy != NULL) {
-    /* if we are phasing out an existing RR instance, unref it. */
-    GRPC_LB_POLICY_UNREF(exec_ctx, glb_policy->rr_policy, "rr_handover");
-  }
-
-  /* Finally update the RR policy to the newly created one */
   glb_policy->rr_policy = new_rr_policy;
 
+  grpc_error *rr_state_error = NULL;
+  const grpc_connectivity_state rr_state =
+      grpc_lb_policy_check_connectivity_locked(exec_ctx, glb_policy->rr_policy,
+                                               &rr_state_error);
+  /* Connectivity state is a function of the RR policy updated/created */
+  update_lb_connectivity_status_locked(exec_ctx, glb_policy, rr_state,
+                                       rr_state_error);
+
   /* Add the gRPC LB's interested_parties pollset_set to that of the newly
    * created RR policy. This will make the RR policy progress upon activity on
    * gRPC LB, which in turn is tied to the application's call */
@@ -719,14 +739,14 @@ static void rr_handover_locked(grpc_exec_ctx *exec_ctx,
    * It'll be deallocated in glb_rr_connectivity_changed() */
   rr_connectivity_data *rr_connectivity =
       gpr_zalloc(sizeof(rr_connectivity_data));
-  grpc_closure_init(&rr_connectivity->on_change,
+  GRPC_CLOSURE_INIT(&rr_connectivity->on_change,
                     glb_rr_connectivity_changed_locked, rr_connectivity,
-                    grpc_combiner_scheduler(glb_policy->base.combiner, false));
+                    grpc_combiner_scheduler(glb_policy->base.combiner));
   rr_connectivity->glb_policy = glb_policy;
-  rr_connectivity->state = new_rr_state;
+  rr_connectivity->state = rr_state;
 
   /* Subscribe to changes to the connectivity of the new RR */
-  GRPC_LB_POLICY_WEAK_REF(&glb_policy->base, "rr_connectivity_cb");
+  GRPC_LB_POLICY_WEAK_REF(&glb_policy->base, "rr_connectivity_sched");
   grpc_lb_policy_notify_on_state_change_locked(exec_ctx, glb_policy->rr_policy,
                                                &rr_connectivity->state,
                                                &rr_connectivity->on_change);
@@ -744,8 +764,8 @@ static void rr_handover_locked(grpc_exec_ctx *exec_ctx,
       gpr_log(GPR_INFO, "Pending pick about to PICK from 0x%" PRIxPTR "",
               (intptr_t)glb_policy->rr_policy);
     }
-    pick_from_internal_rr_locked(exec_ctx, glb_policy->rr_policy,
-                                 &pp->pick_args, pp->target,
+    pick_from_internal_rr_locked(exec_ctx, glb_policy, &pp->pick_args,
+                                 true /* force_async */, pp->target,
                                  &pp->wrapped_on_complete_arg);
   }
 
@@ -763,6 +783,31 @@ static void rr_handover_locked(grpc_exec_ctx *exec_ctx,
   }
 }
 
+/* glb_policy->rr_policy may be NULL (initial handover) */
+static void rr_handover_locked(grpc_exec_ctx *exec_ctx,
+                               glb_lb_policy *glb_policy) {
+  GPR_ASSERT(glb_policy->serverlist != NULL &&
+             glb_policy->serverlist->num_servers > 0);
+
+  if (glb_policy->shutting_down) return;
+
+  grpc_lb_policy_args *args = lb_policy_args_create(exec_ctx, glb_policy);
+  if (glb_policy->rr_policy != NULL) {
+    if (GRPC_TRACER_ON(grpc_lb_glb_trace)) {
+      gpr_log(GPR_DEBUG, "Updating Round Robin policy (%p)",
+              (void *)glb_policy->rr_policy);
+    }
+    grpc_lb_policy_update_locked(exec_ctx, glb_policy->rr_policy, args);
+  } else {
+    create_rr_locked(exec_ctx, glb_policy, args);
+    if (GRPC_TRACER_ON(grpc_lb_glb_trace)) {
+      gpr_log(GPR_DEBUG, "Created new Round Robin policy (%p)",
+              (void *)glb_policy->rr_policy);
+    }
+  }
+  lb_policy_args_destroy(exec_ctx, args);
+}
+
 static void glb_rr_connectivity_changed_locked(grpc_exec_ctx *exec_ctx,
                                                void *arg, grpc_error *error) {
   rr_connectivity_data *rr_connectivity = arg;
@@ -808,18 +853,24 @@ static grpc_slice_hash_table_entry targets_info_entry_create(
   return entry;
 }
 
-/* Returns the target URI for the LB service whose addresses are in \a
- * addresses.  Using this URI, a bidirectional streaming channel will be created
- * for the reception of load balancing updates.
+static int balancer_name_cmp_fn(void *a, void *b) {
+  const char *a_str = a;
+  const char *b_str = b;
+  return strcmp(a_str, b_str);
+}
+
+/* Returns the channel args for the LB channel, used to create a bidirectional
+ * stream for the reception of load balancing updates.
  *
- * The output argument \a targets_info will be updated to contain a mapping of
- * "LB server address" to "balancer name", as reported by the naming system.
- * This mapping will be propagated via the channel arguments of the
- * aforementioned LB streaming channel, to be used by the security connector for
- * secure naming checks. The user is responsible for freeing \a targets_info. */
-static char *get_lb_uri_target_addresses(grpc_exec_ctx *exec_ctx,
-                                         const grpc_lb_addresses *addresses,
-                                         grpc_slice_hash_table **targets_info) {
+ * Inputs:
+ *   - \a addresses: corresponding to the balancers.
+ *   - \a response_generator: in order to propagate updates from the resolver
+ *   above the grpclb policy.
+ *   - \a args: other args inherited from the grpclb policy. */
+static grpc_channel_args *build_lb_channel_args(
+    grpc_exec_ctx *exec_ctx, const grpc_lb_addresses *addresses,
+    grpc_fake_resolver_response_generator *response_generator,
+    const grpc_channel_args *args) {
   size_t num_grpclb_addrs = 0;
   for (size_t i = 0; i < addresses->num_addresses; ++i) {
     if (addresses->addresses[i].is_balancer) ++num_grpclb_addrs;
@@ -828,53 +879,54 @@ static char *get_lb_uri_target_addresses(grpc_exec_ctx *exec_ctx,
    * It's the resolver's responsibility to make sure this policy is only
    * instantiated and used in that case. Otherwise, something has gone wrong. */
   GPR_ASSERT(num_grpclb_addrs > 0);
-
+  grpc_lb_addresses *lb_addresses =
+      grpc_lb_addresses_create(num_grpclb_addrs, NULL);
   grpc_slice_hash_table_entry *targets_info_entries =
-      gpr_malloc(sizeof(*targets_info_entries) * num_grpclb_addrs);
-
-  /* construct a target ipvX://ip1:port1,ip2:port2,... from the addresses in \a
-   * addresses */
-  /* TODO(dgq): support mixed ip version */
-  char **addr_strs = gpr_malloc(sizeof(char *) * num_grpclb_addrs);
-  size_t addr_index = 0;
+      gpr_zalloc(sizeof(*targets_info_entries) * num_grpclb_addrs);
 
-  for (size_t i = 0; i < addresses->num_addresses; i++) {
+  size_t lb_addresses_idx = 0;
+  for (size_t i = 0; i < addresses->num_addresses; ++i) {
+    if (!addresses->addresses[i].is_balancer) continue;
     if (addresses->addresses[i].user_data != NULL) {
       gpr_log(GPR_ERROR,
               "This LB policy doesn't support user data. It will be ignored");
     }
-    if (addresses->addresses[i].is_balancer) {
-      char *addr_str;
-      GPR_ASSERT(grpc_sockaddr_to_string(
-                     &addr_str, &addresses->addresses[i].address, true) > 0);
-      targets_info_entries[addr_index] = targets_info_entry_create(
-          addr_str, addresses->addresses[i].balancer_name);
-      addr_strs[addr_index++] = addr_str;
-    }
+    char *addr_str;
+    GPR_ASSERT(grpc_sockaddr_to_string(
+                   &addr_str, &addresses->addresses[i].address, true) > 0);
+    targets_info_entries[lb_addresses_idx] = targets_info_entry_create(
+        addr_str, addresses->addresses[i].balancer_name);
+    gpr_free(addr_str);
+
+    grpc_lb_addresses_set_address(
+        lb_addresses, lb_addresses_idx++, addresses->addresses[i].address.addr,
+        addresses->addresses[i].address.len, false /* is balancer */,
+        addresses->addresses[i].balancer_name, NULL /* user data */);
   }
-  GPR_ASSERT(addr_index == num_grpclb_addrs);
-
-  size_t uri_path_len;
-  char *uri_path = gpr_strjoin_sep((const char **)addr_strs, num_grpclb_addrs,
-                                   ",", &uri_path_len);
-  for (size_t i = 0; i < num_grpclb_addrs; i++) gpr_free(addr_strs[i]);
-  gpr_free(addr_strs);
-
-  char *target_uri_str = NULL;
-  /* TODO(dgq): Don't assume all addresses will share the scheme of the first
-   * one */
-  gpr_asprintf(&target_uri_str, "%s:%s",
-               grpc_sockaddr_get_uri_scheme(&addresses->addresses[0].address),
-               uri_path);
-  gpr_free(uri_path);
-
-  *targets_info = grpc_slice_hash_table_create(
-      num_grpclb_addrs, targets_info_entries, destroy_balancer_name);
+  GPR_ASSERT(num_grpclb_addrs == lb_addresses_idx);
+  grpc_slice_hash_table *targets_info =
+      grpc_slice_hash_table_create(num_grpclb_addrs, targets_info_entries,
+                                   destroy_balancer_name, balancer_name_cmp_fn);
   gpr_free(targets_info_entries);
 
-  return target_uri_str;
+  grpc_channel_args *lb_channel_args =
+      grpc_lb_policy_grpclb_build_lb_channel_args(exec_ctx, targets_info,
+                                                  response_generator, args);
+
+  grpc_arg lb_channel_addresses_arg =
+      grpc_lb_addresses_create_channel_arg(lb_addresses);
+
+  grpc_channel_args *result = grpc_channel_args_copy_and_add(
+      lb_channel_args, &lb_channel_addresses_arg, 1);
+  grpc_slice_hash_table_unref(exec_ctx, targets_info);
+  grpc_channel_args_destroy(exec_ctx, lb_channel_args);
+  grpc_lb_addresses_destroy(exec_ctx, lb_addresses);
+  return result;
 }
 
+static void glb_lb_channel_on_connectivity_changed_cb(grpc_exec_ctx *exec_ctx,
+                                                      void *arg,
+                                                      grpc_error *error);
 static grpc_lb_policy *glb_create(grpc_exec_ctx *exec_ctx,
                                   grpc_lb_policy_factory *factory,
                                   grpc_lb_policy_args *args) {
@@ -922,32 +974,37 @@ static grpc_lb_policy *glb_create(grpc_exec_ctx *exec_ctx,
 
   // Make sure that GRPC_ARG_LB_POLICY_NAME is set in channel args,
   // since we use this to trigger the client_load_reporting filter.
-  grpc_arg new_arg;
-  new_arg.key = GRPC_ARG_LB_POLICY_NAME;
-  new_arg.type = GRPC_ARG_STRING;
-  new_arg.value.string = "grpclb";
+  grpc_arg new_arg =
+      grpc_channel_arg_string_create(GRPC_ARG_LB_POLICY_NAME, "grpclb");
   static const char *args_to_remove[] = {GRPC_ARG_LB_POLICY_NAME};
   glb_policy->args = grpc_channel_args_copy_and_add_and_remove(
       args->args, args_to_remove, GPR_ARRAY_SIZE(args_to_remove), &new_arg, 1);
 
-  grpc_slice_hash_table *targets_info = NULL;
   /* Create a client channel over them to communicate with a LB service */
-  char *lb_service_target_addresses =
-      get_lb_uri_target_addresses(exec_ctx, addresses, &targets_info);
-  grpc_channel_args *lb_channel_args =
-      get_lb_channel_args(exec_ctx, targets_info, args->args);
+  glb_policy->response_generator =
+      grpc_fake_resolver_response_generator_create();
+  grpc_channel_args *lb_channel_args = build_lb_channel_args(
+      exec_ctx, addresses, glb_policy->response_generator, args->args);
+  char *uri_str;
+  gpr_asprintf(&uri_str, "fake:///%s", glb_policy->server_name);
   glb_policy->lb_channel = grpc_lb_policy_grpclb_create_lb_channel(
-      exec_ctx, lb_service_target_addresses, args->client_channel_factory,
-      lb_channel_args);
-  grpc_slice_hash_table_unref(exec_ctx, targets_info);
+      exec_ctx, uri_str, args->client_channel_factory, lb_channel_args);
+
+  /* Propagate initial resolution */
+  grpc_fake_resolver_response_generator_set_response(
+      exec_ctx, glb_policy->response_generator, lb_channel_args);
   grpc_channel_args_destroy(exec_ctx, lb_channel_args);
-  gpr_free(lb_service_target_addresses);
+  gpr_free(uri_str);
   if (glb_policy->lb_channel == NULL) {
     gpr_free((void *)glb_policy->server_name);
     grpc_channel_args_destroy(exec_ctx, glb_policy->args);
     gpr_free(glb_policy);
     return NULL;
   }
+
+  GRPC_CLOSURE_INIT(&glb_policy->lb_channel_on_connectivity_changed,
+                    glb_lb_channel_on_connectivity_changed_cb, glb_policy,
+                    grpc_combiner_scheduler(args->combiner));
   grpc_lb_policy_init(&glb_policy->base, &glb_lb_policy_vtable, args->combiner);
   grpc_connectivity_state_init(&glb_policy->state_tracker, GRPC_CHANNEL_IDLE,
                                "grpclb");
@@ -963,12 +1020,15 @@ static void glb_destroy(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol) {
   if (glb_policy->client_stats != NULL) {
     grpc_grpclb_client_stats_unref(glb_policy->client_stats);
   }
-  grpc_channel_destroy(glb_policy->lb_channel);
-  glb_policy->lb_channel = NULL;
   grpc_connectivity_state_destroy(exec_ctx, &glb_policy->state_tracker);
   if (glb_policy->serverlist != NULL) {
     grpc_grpclb_destroy_serverlist(glb_policy->serverlist);
   }
+  grpc_fake_resolver_response_generator_unref(glb_policy->response_generator);
+  if (glb_policy->pending_update_args != NULL) {
+    grpc_channel_args_destroy(exec_ctx, glb_policy->pending_update_args->args);
+    gpr_free(glb_policy->pending_update_args);
+  }
   gpr_free(glb_policy);
 }
 
@@ -976,16 +1036,6 @@ static void glb_shutdown_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol) {
   glb_lb_policy *glb_policy = (glb_lb_policy *)pol;
   glb_policy->shutting_down = true;
 
-  pending_pick *pp = glb_policy->pending_picks;
-  glb_policy->pending_picks = NULL;
-  pending_ping *pping = glb_policy->pending_pings;
-  glb_policy->pending_pings = NULL;
-  if (glb_policy->rr_policy) {
-    GRPC_LB_POLICY_UNREF(exec_ctx, glb_policy->rr_policy, "glb_shutdown");
-  }
-  grpc_connectivity_state_set(
-      exec_ctx, &glb_policy->state_tracker, GRPC_CHANNEL_SHUTDOWN,
-      GRPC_ERROR_CREATE_FROM_STATIC_STRING("Channel Shutdown"), "glb_shutdown");
   /* We need a copy of the lb_call pointer because we can't cancell the call
    * while holding glb_policy->mu: lb_on_server_status_received, invoked due to
    * the cancel, needs to acquire that same lock */
@@ -999,17 +1049,41 @@ static void glb_shutdown_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol) {
     grpc_call_cancel(lb_call, NULL);
     /* lb_on_server_status_received will pick up the cancel and clean up */
   }
+  if (glb_policy->retry_timer_active) {
+    grpc_timer_cancel(exec_ctx, &glb_policy->lb_call_retry_timer);
+    glb_policy->retry_timer_active = false;
+  }
+
+  pending_pick *pp = glb_policy->pending_picks;
+  glb_policy->pending_picks = NULL;
+  pending_ping *pping = glb_policy->pending_pings;
+  glb_policy->pending_pings = NULL;
+  if (glb_policy->rr_policy) {
+    GRPC_LB_POLICY_UNREF(exec_ctx, glb_policy->rr_policy, "glb_shutdown");
+  }
+  // We destroy the LB channel here because
+  // glb_lb_channel_on_connectivity_changed_cb needs a valid glb_policy
+  // instance.  Destroying the lb channel in glb_destroy would likely result in
+  // a callback invocation without a valid glb_policy arg.
+  if (glb_policy->lb_channel != NULL) {
+    grpc_channel_destroy(glb_policy->lb_channel);
+    glb_policy->lb_channel = NULL;
+  }
+  grpc_connectivity_state_set(
+      exec_ctx, &glb_policy->state_tracker, GRPC_CHANNEL_SHUTDOWN,
+      GRPC_ERROR_CREATE_FROM_STATIC_STRING("Channel Shutdown"), "glb_shutdown");
+
   while (pp != NULL) {
     pending_pick *next = pp->next;
     *pp->target = NULL;
-    grpc_closure_sched(exec_ctx, &pp->wrapped_on_complete_arg.wrapper_closure,
+    GRPC_CLOSURE_SCHED(exec_ctx, &pp->wrapped_on_complete_arg.wrapper_closure,
                        GRPC_ERROR_NONE);
     pp = next;
   }
 
   while (pping != NULL) {
     pending_ping *next = pping->next;
-    grpc_closure_sched(exec_ctx, &pping->wrapped_notify_arg.wrapper_closure,
+    GRPC_CLOSURE_SCHED(exec_ctx, &pping->wrapped_notify_arg.wrapper_closure,
                        GRPC_ERROR_NONE);
     pping = next;
   }
@@ -1025,7 +1099,7 @@ static void glb_cancel_pick_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol,
     pending_pick *next = pp->next;
     if (pp->target == target) {
       *target = NULL;
-      grpc_closure_sched(exec_ctx, &pp->wrapped_on_complete_arg.wrapper_closure,
+      GRPC_CLOSURE_SCHED(exec_ctx, &pp->wrapped_on_complete_arg.wrapper_closure,
                          GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
                              "Pick Cancelled", &error, 1));
     } else {
@@ -1049,7 +1123,7 @@ static void glb_cancel_picks_locked(grpc_exec_ctx *exec_ctx,
     pending_pick *next = pp->next;
     if ((pp->pick_args.initial_metadata_flags & initial_metadata_flags_mask) ==
         initial_metadata_flags_eq) {
-      grpc_closure_sched(exec_ctx, &pp->wrapped_on_complete_arg.wrapper_closure,
+      GRPC_CLOSURE_SCHED(exec_ctx, &pp->wrapped_on_complete_arg.wrapper_closure,
                          GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
                              "Pick Cancelled", &error, 1));
     } else {
@@ -1084,7 +1158,7 @@ static int glb_pick_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol,
                            grpc_closure *on_complete) {
   if (pick_args->lb_token_mdelem_storage == NULL) {
     *target = NULL;
-    grpc_closure_sched(exec_ctx, on_complete,
+    GRPC_CLOSURE_SCHED(exec_ctx, on_complete,
                        GRPC_ERROR_CREATE_FROM_STATIC_STRING(
                            "No mdelem storage for the LB token. Load reporting "
                            "won't work without it. Failing"));
@@ -1103,7 +1177,7 @@ static int glb_pick_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol,
 
     wrapped_rr_closure_arg *wc_arg = gpr_zalloc(sizeof(wrapped_rr_closure_arg));
 
-    grpc_closure_init(&wc_arg->wrapper_closure, wrapped_rr_closure, wc_arg,
+    GRPC_CLOSURE_INIT(&wc_arg->wrapper_closure, wrapped_rr_closure, wc_arg,
                       grpc_schedule_on_exec_ctx);
     wc_arg->rr_policy = glb_policy->rr_policy;
     wc_arg->target = target;
@@ -1115,8 +1189,9 @@ static int glb_pick_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol,
     wc_arg->lb_token_mdelem_storage = pick_args->lb_token_mdelem_storage;
     wc_arg->initial_metadata = pick_args->initial_metadata;
     wc_arg->free_when_done = wc_arg;
-    pick_done = pick_from_internal_rr_locked(exec_ctx, glb_policy->rr_policy,
-                                             pick_args, target, wc_arg);
+    pick_done =
+        pick_from_internal_rr_locked(exec_ctx, glb_policy, pick_args,
+                                     false /* force_async */, target, wc_arg);
   } else {
     if (GRPC_TRACER_ON(grpc_lb_glb_trace)) {
       gpr_log(GPR_DEBUG,
@@ -1173,9 +1248,9 @@ static void schedule_next_client_load_report(grpc_exec_ctx *exec_ctx,
   const gpr_timespec now = gpr_now(GPR_CLOCK_MONOTONIC);
   const gpr_timespec next_client_load_report_time =
       gpr_time_add(now, glb_policy->client_stats_report_interval);
-  grpc_closure_init(&glb_policy->client_load_report_closure,
+  GRPC_CLOSURE_INIT(&glb_policy->client_load_report_closure,
                     send_client_load_report_locked, glb_policy,
-                    grpc_combiner_scheduler(glb_policy->base.combiner, false));
+                    grpc_combiner_scheduler(glb_policy->base.combiner));
   grpc_timer_init(exec_ctx, &glb_policy->client_load_report_timer,
                   next_client_load_report_time,
                   &glb_policy->client_load_report_closure, now);
@@ -1201,9 +1276,9 @@ static void do_send_client_load_report_locked(grpc_exec_ctx *exec_ctx,
   memset(&op, 0, sizeof(op));
   op.op = GRPC_OP_SEND_MESSAGE;
   op.data.send_message.send_message = glb_policy->client_load_report_payload;
-  grpc_closure_init(&glb_policy->client_load_report_closure,
+  GRPC_CLOSURE_INIT(&glb_policy->client_load_report_closure,
                     client_load_report_done_locked, glb_policy,
-                    grpc_combiner_scheduler(glb_policy->base.combiner, false));
+                    grpc_combiner_scheduler(glb_policy->base.combiner));
   grpc_call_error call_error = grpc_call_start_batch_and_execute(
       exec_ctx, glb_policy->lb_call, &op, 1,
       &glb_policy->client_load_report_closure);
@@ -1271,6 +1346,7 @@ static void lb_call_init_locked(grpc_exec_ctx *exec_ctx,
                                 glb_lb_policy *glb_policy) {
   GPR_ASSERT(glb_policy->server_name != NULL);
   GPR_ASSERT(glb_policy->server_name[0] != '\0');
+  GPR_ASSERT(glb_policy->lb_call == NULL);
   GPR_ASSERT(!glb_policy->shutting_down);
 
   /* Note the following LB call progresses every time there's activity in \a
@@ -1306,15 +1382,15 @@ static void lb_call_init_locked(grpc_exec_ctx *exec_ctx,
   grpc_slice_unref_internal(exec_ctx, request_payload_slice);
   grpc_grpclb_request_destroy(request);
 
-  grpc_closure_init(&glb_policy->lb_on_sent_initial_request,
+  GRPC_CLOSURE_INIT(&glb_policy->lb_on_sent_initial_request,
                     lb_on_sent_initial_request_locked, glb_policy,
-                    grpc_combiner_scheduler(glb_policy->base.combiner, false));
-  grpc_closure_init(&glb_policy->lb_on_server_status_received,
+                    grpc_combiner_scheduler(glb_policy->base.combiner));
+  GRPC_CLOSURE_INIT(&glb_policy->lb_on_server_status_received,
                     lb_on_server_status_received_locked, glb_policy,
-                    grpc_combiner_scheduler(glb_policy->base.combiner, false));
-  grpc_closure_init(&glb_policy->lb_on_response_received,
+                    grpc_combiner_scheduler(glb_policy->base.combiner));
+  GRPC_CLOSURE_INIT(&glb_policy->lb_on_response_received,
                     lb_on_response_received_locked, glb_policy,
-                    grpc_combiner_scheduler(glb_policy->base.combiner, false));
+                    grpc_combiner_scheduler(glb_policy->base.combiner));
 
   gpr_backoff_init(&glb_policy->lb_call_backoff_state,
                    GRPC_GRPCLB_INITIAL_CONNECT_BACKOFF_SECONDS,
@@ -1356,8 +1432,10 @@ static void query_for_backends_locked(grpc_exec_ctx *exec_ctx,
   lb_call_init_locked(exec_ctx, glb_policy);
 
   if (GRPC_TRACER_ON(grpc_lb_glb_trace)) {
-    gpr_log(GPR_INFO, "Query for backends (grpclb: %p, lb_call: %p)",
-            (void *)glb_policy, (void *)glb_policy->lb_call);
+    gpr_log(GPR_INFO,
+            "Query for backends (grpclb: %p, lb_channel: %p, lb_call: %p)",
+            (void *)glb_policy, (void *)glb_policy->lb_channel,
+            (void *)glb_policy->lb_call);
   }
   GPR_ASSERT(glb_policy->lb_call != NULL);
 
@@ -1517,7 +1595,7 @@ static void lb_on_response_received_locked(grpc_exec_ctx *exec_ctx, void *arg,
              * serverlist instance will be destroyed either upon the next
              * update or in glb_destroy() */
             glb_policy->serverlist = serverlist;
-
+            glb_policy->serverlist_index = 0;
             rr_handover_locked(exec_ctx, glb_policy);
           }
         } else {
@@ -1561,8 +1639,8 @@ static void lb_on_response_received_locked(grpc_exec_ctx *exec_ctx, void *arg,
 static void lb_call_on_retry_timer_locked(grpc_exec_ctx *exec_ctx, void *arg,
                                           grpc_error *error) {
   glb_lb_policy *glb_policy = arg;
-
-  if (!glb_policy->shutting_down) {
+  glb_policy->retry_timer_active = false;
+  if (!glb_policy->shutting_down && error == GRPC_ERROR_NONE) {
     if (GRPC_TRACER_ON(grpc_lb_glb_trace)) {
       gpr_log(GPR_INFO, "Restaring call to LB server (grpclb %p)",
               (void *)glb_policy);
@@ -1570,31 +1648,32 @@ static void lb_call_on_retry_timer_locked(grpc_exec_ctx *exec_ctx, void *arg,
     GPR_ASSERT(glb_policy->lb_call == NULL);
     query_for_backends_locked(exec_ctx, glb_policy);
   }
-  GRPC_LB_POLICY_WEAK_UNREF(exec_ctx, &glb_policy->base,
-                            "grpclb_on_retry_timer");
+  GRPC_LB_POLICY_WEAK_UNREF(exec_ctx, &glb_policy->base, "grpclb_retry_timer");
 }
 
 static void lb_on_server_status_received_locked(grpc_exec_ctx *exec_ctx,
                                                 void *arg, grpc_error *error) {
   glb_lb_policy *glb_policy = arg;
-
   GPR_ASSERT(glb_policy->lb_call != NULL);
-
   if (GRPC_TRACER_ON(grpc_lb_glb_trace)) {
     char *status_details =
         grpc_slice_to_c_string(glb_policy->lb_call_status_details);
-    gpr_log(GPR_DEBUG,
+    gpr_log(GPR_INFO,
             "Status from LB server received. Status = %d, Details = '%s', "
-            "(call: %p)",
+            "(call: %p), error %p",
             glb_policy->lb_call_status, status_details,
-            (void *)glb_policy->lb_call);
+            (void *)glb_policy->lb_call, (void *)error);
     gpr_free(status_details);
   }
-
   /* We need to perform cleanups no matter what. */
   lb_call_destroy_locked(exec_ctx, glb_policy);
-
-  if (!glb_policy->shutting_down) {
+  if (glb_policy->started_picking && glb_policy->updating_lb_call) {
+    if (glb_policy->retry_timer_active) {
+      grpc_timer_cancel(exec_ctx, &glb_policy->lb_call_retry_timer);
+    }
+    if (!glb_policy->shutting_down) start_picking_locked(exec_ctx, glb_policy);
+    glb_policy->updating_lb_call = false;
+  } else if (!glb_policy->shutting_down) {
     /* if we aren't shutting down, restart the LB client call after some time */
     gpr_timespec now = gpr_now(GPR_CLOCK_MONOTONIC);
     gpr_timespec next_try =
@@ -1604,16 +1683,18 @@ static void lb_on_server_status_received_locked(grpc_exec_ctx *exec_ctx,
               (void *)glb_policy);
       gpr_timespec timeout = gpr_time_sub(next_try, now);
       if (gpr_time_cmp(timeout, gpr_time_0(timeout.clock_type)) > 0) {
-        gpr_log(GPR_DEBUG, "... retrying in %" PRId64 ".%09d seconds.",
+        gpr_log(GPR_DEBUG,
+                "... retry_timer_active in %" PRId64 ".%09d seconds.",
                 timeout.tv_sec, timeout.tv_nsec);
       } else {
-        gpr_log(GPR_DEBUG, "... retrying immediately.");
+        gpr_log(GPR_DEBUG, "... retry_timer_active immediately.");
       }
     }
     GRPC_LB_POLICY_WEAK_REF(&glb_policy->base, "grpclb_retry_timer");
-    grpc_closure_init(
-        &glb_policy->lb_on_call_retry, lb_call_on_retry_timer_locked,
-        glb_policy, grpc_combiner_scheduler(glb_policy->base.combiner, false));
+    GRPC_CLOSURE_INIT(&glb_policy->lb_on_call_retry,
+                      lb_call_on_retry_timer_locked, glb_policy,
+                      grpc_combiner_scheduler(glb_policy->base.combiner));
+    glb_policy->retry_timer_active = true;
     grpc_timer_init(exec_ctx, &glb_policy->lb_call_retry_timer, next_try,
                     &glb_policy->lb_on_call_retry, now);
   }
@@ -1621,6 +1702,138 @@ static void lb_on_server_status_received_locked(grpc_exec_ctx *exec_ctx,
                             "lb_on_server_status_received");
 }
 
+static void glb_update_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *policy,
+                              const grpc_lb_policy_args *args) {
+  glb_lb_policy *glb_policy = (glb_lb_policy *)policy;
+
+  if (glb_policy->updating_lb_channel) {
+    if (GRPC_TRACER_ON(grpc_lb_glb_trace)) {
+      gpr_log(GPR_INFO,
+              "Update already in progress for grpclb %p. Deferring update.",
+              (void *)glb_policy);
+    }
+    if (glb_policy->pending_update_args != NULL) {
+      grpc_channel_args_destroy(exec_ctx,
+                                glb_policy->pending_update_args->args);
+      gpr_free(glb_policy->pending_update_args);
+    }
+    glb_policy->pending_update_args =
+        gpr_zalloc(sizeof(*glb_policy->pending_update_args));
+    glb_policy->pending_update_args->client_channel_factory =
+        args->client_channel_factory;
+    glb_policy->pending_update_args->args = grpc_channel_args_copy(args->args);
+    glb_policy->pending_update_args->combiner = args->combiner;
+    return;
+  }
+
+  glb_policy->updating_lb_channel = true;
+  // Propagate update to lb_channel (pick first).
+  const grpc_arg *arg =
+      grpc_channel_args_find(args->args, GRPC_ARG_LB_ADDRESSES);
+  if (arg == NULL || arg->type != GRPC_ARG_POINTER) {
+    if (glb_policy->lb_channel == NULL) {
+      // If we don't have a current channel to the LB, go into TRANSIENT
+      // FAILURE.
+      grpc_connectivity_state_set(
+          exec_ctx, &glb_policy->state_tracker, GRPC_CHANNEL_TRANSIENT_FAILURE,
+          GRPC_ERROR_CREATE_FROM_STATIC_STRING("Missing update in args"),
+          "glb_update_missing");
+    } else {
+      // otherwise, keep using the current LB channel (ignore this update).
+      gpr_log(GPR_ERROR,
+              "No valid LB addresses channel arg for grpclb %p update, "
+              "ignoring.",
+              (void *)glb_policy);
+    }
+  }
+  const grpc_lb_addresses *addresses = arg->value.pointer.p;
+  GPR_ASSERT(glb_policy->lb_channel != NULL);
+  grpc_channel_args *lb_channel_args = build_lb_channel_args(
+      exec_ctx, addresses, glb_policy->response_generator, args->args);
+  /* Propagate updates to the LB channel through the fake resolver */
+  grpc_fake_resolver_response_generator_set_response(
+      exec_ctx, glb_policy->response_generator, lb_channel_args);
+  grpc_channel_args_destroy(exec_ctx, lb_channel_args);
+
+  if (!glb_policy->watching_lb_channel) {
+    // Watch the LB channel connectivity for connection.
+    glb_policy->lb_channel_connectivity = GRPC_CHANNEL_INIT;
+    grpc_channel_element *client_channel_elem = grpc_channel_stack_last_element(
+        grpc_channel_get_channel_stack(glb_policy->lb_channel));
+    GPR_ASSERT(client_channel_elem->filter == &grpc_client_channel_filter);
+    glb_policy->watching_lb_channel = true;
+    GRPC_LB_POLICY_WEAK_REF(&glb_policy->base, "watch_lb_channel_connectivity");
+    grpc_client_channel_watch_connectivity_state(
+        exec_ctx, client_channel_elem,
+        grpc_polling_entity_create_from_pollset_set(
+            glb_policy->base.interested_parties),
+        &glb_policy->lb_channel_connectivity,
+        &glb_policy->lb_channel_on_connectivity_changed, NULL);
+  }
+}
+
+// Invoked as part of the update process. It continues watching the LB channel
+// until it shuts down or becomes READY. It's invoked even if the LB channel
+// stayed READY throughout the update (for example if the update is identical).
+static void glb_lb_channel_on_connectivity_changed_cb(grpc_exec_ctx *exec_ctx,
+                                                      void *arg,
+                                                      grpc_error *error) {
+  glb_lb_policy *glb_policy = arg;
+  if (glb_policy->shutting_down) goto done;
+  // Re-initialize the lb_call. This should also take care of updating the
+  // embedded RR policy. Note that the current RR policy, if any, will stay in
+  // effect until an update from the new lb_call is received.
+  switch (glb_policy->lb_channel_connectivity) {
+    case GRPC_CHANNEL_INIT:
+    case GRPC_CHANNEL_CONNECTING:
+    case GRPC_CHANNEL_TRANSIENT_FAILURE: {
+      /* resub. */
+      grpc_channel_element *client_channel_elem =
+          grpc_channel_stack_last_element(
+              grpc_channel_get_channel_stack(glb_policy->lb_channel));
+      GPR_ASSERT(client_channel_elem->filter == &grpc_client_channel_filter);
+      grpc_client_channel_watch_connectivity_state(
+          exec_ctx, client_channel_elem,
+          grpc_polling_entity_create_from_pollset_set(
+              glb_policy->base.interested_parties),
+          &glb_policy->lb_channel_connectivity,
+          &glb_policy->lb_channel_on_connectivity_changed, NULL);
+      break;
+    }
+    case GRPC_CHANNEL_IDLE:
+      // lb channel inactive (probably shutdown prior to update). Restart lb
+      // call to kick the lb channel into gear.
+      GPR_ASSERT(glb_policy->lb_call == NULL);
+    /* fallthrough */
+    case GRPC_CHANNEL_READY:
+      if (glb_policy->lb_call != NULL) {
+        glb_policy->updating_lb_channel = false;
+        glb_policy->updating_lb_call = true;
+        grpc_call_cancel(glb_policy->lb_call, NULL);
+        // lb_on_server_status_received will pick up the cancel and reinit
+        // lb_call.
+        if (glb_policy->pending_update_args != NULL) {
+          const grpc_lb_policy_args *args = glb_policy->pending_update_args;
+          glb_policy->pending_update_args = NULL;
+          glb_update_locked(exec_ctx, &glb_policy->base, args);
+        }
+      } else if (glb_policy->started_picking && !glb_policy->shutting_down) {
+        if (glb_policy->retry_timer_active) {
+          grpc_timer_cancel(exec_ctx, &glb_policy->lb_call_retry_timer);
+          glb_policy->retry_timer_active = false;
+        }
+        start_picking_locked(exec_ctx, glb_policy);
+      }
+    /* fallthrough */
+    case GRPC_CHANNEL_SHUTDOWN:
+    done:
+      glb_policy->watching_lb_channel = false;
+      GRPC_LB_POLICY_WEAK_UNREF(exec_ctx, &glb_policy->base,
+                                "watch_lb_channel_connectivity_cb_shutdown");
+      break;
+  }
+}
+
 /* Code wiring the policy with the rest of the core */
 static const grpc_lb_policy_vtable glb_lb_policy_vtable = {
     glb_destroy,
@@ -1631,7 +1844,8 @@ static const grpc_lb_policy_vtable glb_lb_policy_vtable = {
     glb_ping_one_locked,
     glb_exit_idle_locked,
     glb_check_connectivity_locked,
-    glb_notify_on_state_change_locked};
+    glb_notify_on_state_change_locked,
+    glb_update_locked};
 
 static void glb_factory_ref(grpc_lb_policy_factory *factory) {}
 
@@ -1665,7 +1879,10 @@ static bool maybe_add_client_load_reporting_filter(
 
 void grpc_lb_policy_grpclb_init() {
   grpc_register_lb_policy(grpc_glb_lb_factory_create());
-  grpc_register_tracer("glb", &grpc_lb_glb_trace);
+  grpc_register_tracer(&grpc_lb_glb_trace);
+#ifndef NDEBUG
+  grpc_register_tracer(&grpc_trace_lb_policy_refcount);
+#endif
   grpc_channel_init_register_stage(GRPC_CLIENT_SUBCHANNEL,
                                    GRPC_CHANNEL_INIT_BUILTIN_PRIORITY,
                                    maybe_add_client_load_reporting_filter,
diff --git a/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.h b/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.h
index b069fae2f8..63ad66c5e9 100644
--- a/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.h
+++ b/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel.c b/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel.c
index d6201f2387..f2967182e2 100644
--- a/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel.c
+++ b/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2017, Google Inc.
- * All rights reserved.
+ * Copyright 2017 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -50,28 +35,37 @@ grpc_channel *grpc_lb_policy_grpclb_create_lb_channel(
   return lb_channel;
 }
 
-grpc_channel_args *get_lb_channel_args(grpc_exec_ctx *exec_ctx,
-                                       grpc_slice_hash_table *targets_info,
-                                       const grpc_channel_args *args) {
-  /* We strip out the channel arg for the LB policy name, since we want
-   * to use the default (pick_first) in this case.
+grpc_channel_args *grpc_lb_policy_grpclb_build_lb_channel_args(
+    grpc_exec_ctx *exec_ctx, grpc_slice_hash_table *targets_info,
+    grpc_fake_resolver_response_generator *response_generator,
+    const grpc_channel_args *args) {
+  const grpc_arg to_add[] = {
+      grpc_fake_resolver_response_generator_arg(response_generator)};
+  /* We remove:
    *
-   * We also strip out the channel arg for the resolved addresses, since
-   * that will be generated by the name resolver used in the LB channel.
-   * Note that the LB channel will use the sockaddr resolver, so this
-   * won't actually generate a query to DNS (or some other name service).
-   * However, the addresses returned by the sockaddr resolver will have
-   * is_balancer=false, whereas our own addresses have is_balancer=true.
-   * We need the LB channel to return addresses with is_balancer=false
-   * so that it does not wind up recursively using the grpclb LB policy,
-   * as per the special case logic in client_channel.c.
+   * - The channel arg for the LB policy name, since we want to use the default
+   *   (pick_first) in this case.
    *
-   * Lastly, we also strip out the channel arg for the server URI,
-   * since that will be different for the LB channel than for the parent
-   * channel (the client channel factory will re-add this arg with
-   * the right value). */
+   * - The channel arg for the resolved addresses, since that will be generated
+   *   by the name resolver used in the LB channel.  Note that the LB channel
+   *   will use the fake resolver, so this won't actually generate a query
+   *   to DNS (or some other name service).  However, the addresses returned by
+   *   the fake resolver will have is_balancer=false, whereas our own
+   *   addresses have is_balancer=true.  We need the LB channel to return
+   *   addresses with is_balancer=false so that it does not wind up recursively
+   *   using the grpclb LB policy, as per the special case logic in
+   *   client_channel.c.
+   *
+   * - The channel arg for the server URI, since that will be different for the
+   *   LB channel than for the parent channel (the client channel factory will
+   *   re-add this arg with the right value).
+   *
+   * - The fake resolver generator, because we are replacing it with the one
+   *   from the grpclb policy, used to propagate updates to the LB channel. */
   static const char *keys_to_remove[] = {
-      GRPC_ARG_LB_POLICY_NAME, GRPC_ARG_LB_ADDRESSES, GRPC_ARG_SERVER_URI};
-  return grpc_channel_args_copy_and_remove(args, keys_to_remove,
-                                           GPR_ARRAY_SIZE(keys_to_remove));
+      GRPC_ARG_LB_POLICY_NAME, GRPC_ARG_LB_ADDRESSES, GRPC_ARG_SERVER_URI,
+      GRPC_ARG_FAKE_RESOLVER_RESPONSE_GENERATOR};
+  return grpc_channel_args_copy_and_add_and_remove(
+      args, keys_to_remove, GPR_ARRAY_SIZE(keys_to_remove), to_add,
+      GPR_ARRAY_SIZE(to_add));
 }
diff --git a/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel.h b/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel.h
index 9730c971d9..6120bf53f7 100644
--- a/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel.h
+++ b/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2017, Google Inc.
- * All rights reserved.
+ * Copyright 2017 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -35,6 +20,7 @@
 #define GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_LB_POLICY_GRPCLB_GRPCLB_CHANNEL_H
 
 #include "src/core/ext/filters/client_channel/lb_policy_factory.h"
+#include "src/core/ext/filters/client_channel/resolver/fake/fake_resolver.h"
 #include "src/core/lib/slice/slice_hash_table.h"
 
 /** Create the channel used for communicating with an LB service.
@@ -49,9 +35,10 @@ grpc_channel *grpc_lb_policy_grpclb_create_lb_channel(
     grpc_client_channel_factory *client_channel_factory,
     grpc_channel_args *args);
 
-grpc_channel_args *get_lb_channel_args(grpc_exec_ctx *exec_ctx,
-                                       grpc_slice_hash_table *targets_info,
-                                       const grpc_channel_args *args);
+grpc_channel_args *grpc_lb_policy_grpclb_build_lb_channel_args(
+    grpc_exec_ctx *exec_ctx, grpc_slice_hash_table *targets_info,
+    grpc_fake_resolver_response_generator *response_generator,
+    const grpc_channel_args *args);
 
 #endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_LB_POLICY_GRPCLB_GRPCLB_CHANNEL_H \
           */
diff --git a/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel_secure.c b/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel_secure.c
index a145cba63c..2681b2a079 100644
--- a/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel_secure.c
+++ b/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel_secure.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2017, Google Inc.
- * All rights reserved.
+ * Copyright 2017 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -76,32 +61,39 @@ grpc_channel *grpc_lb_policy_grpclb_create_lb_channel(
   return lb_channel;
 }
 
-grpc_channel_args *get_lb_channel_args(grpc_exec_ctx *exec_ctx,
-                                       grpc_slice_hash_table *targets_info,
-                                       const grpc_channel_args *args) {
-  const grpc_arg targets_info_arg =
-      grpc_lb_targets_info_create_channel_arg(targets_info);
-  /* We strip out the channel arg for the LB policy name, since we want
-   * to use the default (pick_first) in this case.
+grpc_channel_args *grpc_lb_policy_grpclb_build_lb_channel_args(
+    grpc_exec_ctx *exec_ctx, grpc_slice_hash_table *targets_info,
+    grpc_fake_resolver_response_generator *response_generator,
+    const grpc_channel_args *args) {
+  const grpc_arg to_add[] = {
+      grpc_lb_targets_info_create_channel_arg(targets_info),
+      grpc_fake_resolver_response_generator_arg(response_generator)};
+  /* We remove:
    *
-   * We also strip out the channel arg for the resolved addresses, since
-   * that will be generated by the name resolver used in the LB channel.
-   * Note that the LB channel will use the sockaddr resolver, so this
-   * won't actually generate a query to DNS (or some other name service).
-   * However, the addresses returned by the sockaddr resolver will have
-   * is_balancer=false, whereas our own addresses have is_balancer=true.
-   * We need the LB channel to return addresses with is_balancer=false
-   * so that it does not wind up recursively using the grpclb LB policy,
-   * as per the special case logic in client_channel.c.
+   * - The channel arg for the LB policy name, since we want to use the default
+   *   (pick_first) in this case.
    *
-   * Lastly, we also strip out the channel arg for the server URI,
-   * since that will be different for the LB channel than for the parent
-   * channel (the client channel factory will re-add this arg with
-   * the right value). */
+   * - The channel arg for the resolved addresses, since that will be generated
+   *   by the name resolver used in the LB channel.  Note that the LB channel
+   *   will use the fake resolver, so this won't actually generate a query
+   *   to DNS (or some other name service).  However, the addresses returned by
+   *   the fake resolver will have is_balancer=false, whereas our own
+   *   addresses have is_balancer=true.  We need the LB channel to return
+   *   addresses with is_balancer=false so that it does not wind up recursively
+   *   using the grpclb LB policy, as per the special case logic in
+   *   client_channel.c.
+   *
+   * - The channel arg for the server URI, since that will be different for the
+   *   LB channel than for the parent channel (the client channel factory will
+   *   re-add this arg with the right value).
+   *
+   * - The fake resolver generator, because we are replacing it with the one
+   *   from the grpclb policy, used to propagate updates to the LB channel. */
   static const char *keys_to_remove[] = {
-      GRPC_ARG_LB_POLICY_NAME, GRPC_ARG_LB_ADDRESSES, GRPC_ARG_SERVER_URI};
+      GRPC_ARG_LB_POLICY_NAME, GRPC_ARG_LB_ADDRESSES, GRPC_ARG_SERVER_URI,
+      GRPC_ARG_FAKE_RESOLVER_RESPONSE_GENERATOR};
   /* Add the targets info table to be used for secure naming */
   return grpc_channel_args_copy_and_add_and_remove(
-      args, keys_to_remove, GPR_ARRAY_SIZE(keys_to_remove), &targets_info_arg,
-      1);
+      args, keys_to_remove, GPR_ARRAY_SIZE(keys_to_remove), to_add,
+      GPR_ARRAY_SIZE(to_add));
 }
diff --git a/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_client_stats.c b/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_client_stats.c
index 444c03b9aa..c762443b7c 100644
--- a/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_client_stats.c
+++ b/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_client_stats.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2017, Google Inc.
- * All rights reserved.
+ * Copyright 2017 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_client_stats.h b/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_client_stats.h
index 0af4a919f8..4bb47d5c5c 100644
--- a/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_client_stats.h
+++ b/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_client_stats.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2017, Google Inc.
- * All rights reserved.
+ * Copyright 2017 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/filters/client_channel/lb_policy/grpclb/load_balancer_api.c b/src/core/ext/filters/client_channel/lb_policy/grpclb/load_balancer_api.c
index 81b6932fae..bec7c97a78 100644
--- a/src/core/ext/filters/client_channel/lb_policy/grpclb/load_balancer_api.c
+++ b/src/core/ext/filters/client_channel/lb_policy/grpclb/load_balancer_api.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -37,44 +22,39 @@
 
 #include <grpc/support/alloc.h>
 
+/* invoked once for every Server in ServerList */
+static bool count_serverlist(pb_istream_t *stream, const pb_field_t *field,
+                             void **arg) {
+  grpc_grpclb_serverlist *sl = *arg;
+  grpc_grpclb_server server;
+  if (!pb_decode(stream, grpc_lb_v1_Server_fields, &server)) {
+    gpr_log(GPR_ERROR, "nanopb error: %s", PB_GET_ERROR(stream));
+    return false;
+  }
+  ++sl->num_servers;
+  return true;
+}
+
 typedef struct decode_serverlist_arg {
-  /* The first pass counts the number of servers in the server list. The second
-   * one allocates and decodes. */
-  bool first_pass;
   /* The decoding callback is invoked once per server in serverlist. Remember
    * which index of the serverlist are we currently decoding */
   size_t decoding_idx;
-  /* Populated after the first pass. Number of server in the input serverlist */
-  size_t num_servers;
   /* The decoded serverlist */
-  grpc_grpclb_server **servers;
+  grpc_grpclb_serverlist *serverlist;
 } decode_serverlist_arg;
 
 /* invoked once for every Server in ServerList */
 static bool decode_serverlist(pb_istream_t *stream, const pb_field_t *field,
                               void **arg) {
   decode_serverlist_arg *dec_arg = *arg;
-  if (dec_arg->first_pass) { /* count how many server do we have */
-    grpc_grpclb_server server;
-    if (!pb_decode(stream, grpc_lb_v1_Server_fields, &server)) {
-      gpr_log(GPR_ERROR, "nanopb error: %s", PB_GET_ERROR(stream));
-      return false;
-    }
-    dec_arg->num_servers++;
-  } else { /* second pass. Actually decode. */
-    grpc_grpclb_server *server = gpr_zalloc(sizeof(grpc_grpclb_server));
-    GPR_ASSERT(dec_arg->num_servers > 0);
-    if (dec_arg->decoding_idx == 0) { /* first iteration of second pass */
-      dec_arg->servers =
-          gpr_malloc(sizeof(grpc_grpclb_server *) * dec_arg->num_servers);
-    }
-    if (!pb_decode(stream, grpc_lb_v1_Server_fields, server)) {
-      gpr_log(GPR_ERROR, "nanopb error: %s", PB_GET_ERROR(stream));
-      return false;
-    }
-    dec_arg->servers[dec_arg->decoding_idx++] = server;
+  GPR_ASSERT(dec_arg->serverlist->num_servers >= dec_arg->decoding_idx);
+  grpc_grpclb_server *server = gpr_zalloc(sizeof(grpc_grpclb_server));
+  if (!pb_decode(stream, grpc_lb_v1_Server_fields, server)) {
+    gpr_free(server);
+    gpr_log(GPR_ERROR, "nanopb error: %s", PB_GET_ERROR(stream));
+    return false;
   }
-
+  dec_arg->serverlist->servers[dec_arg->decoding_idx++] = server;
   return true;
 }
 
@@ -165,36 +145,38 @@ grpc_grpclb_initial_response *grpc_grpclb_initial_response_parse(
 
 grpc_grpclb_serverlist *grpc_grpclb_response_parse_serverlist(
     grpc_slice encoded_grpc_grpclb_response) {
-  bool status;
-  decode_serverlist_arg arg;
   pb_istream_t stream =
       pb_istream_from_buffer(GRPC_SLICE_START_PTR(encoded_grpc_grpclb_response),
                              GRPC_SLICE_LENGTH(encoded_grpc_grpclb_response));
   pb_istream_t stream_at_start = stream;
+  grpc_grpclb_serverlist *sl = gpr_zalloc(sizeof(grpc_grpclb_serverlist));
   grpc_grpclb_response res;
   memset(&res, 0, sizeof(grpc_grpclb_response));
-  memset(&arg, 0, sizeof(decode_serverlist_arg));
-
-  res.server_list.servers.funcs.decode = decode_serverlist;
-  res.server_list.servers.arg = &arg;
-  arg.first_pass = true;
-  status = pb_decode(&stream, grpc_lb_v1_LoadBalanceResponse_fields, &res);
+  // First pass: count number of servers.
+  res.server_list.servers.funcs.decode = count_serverlist;
+  res.server_list.servers.arg = sl;
+  bool status = pb_decode(&stream, grpc_lb_v1_LoadBalanceResponse_fields, &res);
   if (!status) {
+    gpr_free(sl);
     gpr_log(GPR_ERROR, "nanopb error: %s", PB_GET_ERROR(&stream));
     return NULL;
   }
-
-  arg.first_pass = false;
-  status =
-      pb_decode(&stream_at_start, grpc_lb_v1_LoadBalanceResponse_fields, &res);
-  if (!status) {
-    gpr_log(GPR_ERROR, "nanopb error: %s", PB_GET_ERROR(&stream));
-    return NULL;
+  // Second pass: populate servers.
+  if (sl->num_servers > 0) {
+    sl->servers = gpr_zalloc(sizeof(grpc_grpclb_server *) * sl->num_servers);
+    decode_serverlist_arg decode_arg;
+    memset(&decode_arg, 0, sizeof(decode_arg));
+    decode_arg.serverlist = sl;
+    res.server_list.servers.funcs.decode = decode_serverlist;
+    res.server_list.servers.arg = &decode_arg;
+    status = pb_decode(&stream_at_start, grpc_lb_v1_LoadBalanceResponse_fields,
+                       &res);
+    if (!status) {
+      grpc_grpclb_destroy_serverlist(sl);
+      gpr_log(GPR_ERROR, "nanopb error: %s", PB_GET_ERROR(&stream));
+      return NULL;
+    }
   }
-
-  grpc_grpclb_serverlist *sl = gpr_zalloc(sizeof(grpc_grpclb_serverlist));
-  sl->num_servers = arg.num_servers;
-  sl->servers = arg.servers;
   if (res.server_list.has_expiration_interval) {
     sl->expiration_interval = res.server_list.expiration_interval;
   }
@@ -228,7 +210,7 @@ grpc_grpclb_serverlist *grpc_grpclb_serverlist_copy(
 
 bool grpc_grpclb_serverlist_equals(const grpc_grpclb_serverlist *lhs,
                                    const grpc_grpclb_serverlist *rhs) {
-  if ((lhs == NULL) || (rhs == NULL)) {
+  if (lhs == NULL || rhs == NULL) {
     return false;
   }
   if (lhs->num_servers != rhs->num_servers) {
diff --git a/src/core/ext/filters/client_channel/lb_policy/grpclb/load_balancer_api.h b/src/core/ext/filters/client_channel/lb_policy/grpclb/load_balancer_api.h
index 06873821bd..ef8d563edc 100644
--- a/src/core/ext/filters/client_channel/lb_policy/grpclb/load_balancer_api.h
+++ b/src/core/ext/filters/client_channel/lb_policy/grpclb/load_balancer_api.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -51,7 +36,7 @@ typedef grpc_lb_v1_LoadBalanceRequest grpc_grpclb_request;
 typedef grpc_lb_v1_InitialLoadBalanceResponse grpc_grpclb_initial_response;
 typedef grpc_lb_v1_Server grpc_grpclb_server;
 typedef grpc_lb_v1_Duration grpc_grpclb_duration;
-typedef struct grpc_grpclb_serverlist {
+typedef struct {
   grpc_grpclb_server **servers;
   size_t num_servers;
   grpc_grpclb_duration expiration_interval;
diff --git a/src/core/ext/filters/client_channel/lb_policy/pick_first/pick_first.c b/src/core/ext/filters/client_channel/lb_policy/pick_first/pick_first.c
index b1c5dfc61c..fd0fb41fb9 100644
--- a/src/core/ext/filters/client_channel/lb_policy/pick_first/pick_first.c
+++ b/src/core/ext/filters/client_channel/lb_policy/pick_first/pick_first.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -37,11 +22,15 @@
 
 #include "src/core/ext/filters/client_channel/lb_policy_registry.h"
 #include "src/core/ext/filters/client_channel/subchannel.h"
+#include "src/core/ext/filters/client_channel/subchannel_index.h"
 #include "src/core/lib/channel/channel_args.h"
 #include "src/core/lib/iomgr/combiner.h"
 #include "src/core/lib/iomgr/sockaddr_utils.h"
 #include "src/core/lib/transport/connectivity_state.h"
 
+grpc_tracer_flag grpc_lb_pick_first_trace =
+    GRPC_TRACER_INITIALIZER(false, "pick_first");
+
 typedef struct pending_pick {
   struct pending_pick *next;
   uint32_t initial_metadata_flags;
@@ -54,7 +43,9 @@ typedef struct {
   grpc_lb_policy base;
   /** all our subchannels */
   grpc_subchannel **subchannels;
+  grpc_subchannel **new_subchannels;
   size_t num_subchannels;
+  size_t num_new_subchannels;
 
   grpc_closure connectivity_changed;
 
@@ -63,10 +54,19 @@ typedef struct {
   /** the selected channel */
   grpc_connected_subchannel *selected;
 
+  /** the subchannel key for \a selected, or NULL if \a selected not set */
+  const grpc_subchannel_key *selected_key;
+
   /** have we started picking? */
-  int started_picking;
+  bool started_picking;
   /** are we shut down? */
-  int shutdown;
+  bool shutdown;
+  /** are we updating the selected subchannel? */
+  bool updating_selected;
+  /** are we updating the subchannel candidates? */
+  bool updating_subchannels;
+  /** args from the latest update received while already updating, or NULL */
+  grpc_lb_policy_args *pending_update_args;
   /** which subchannel are we watching? */
   size_t checking_subchannel;
   /** what is the connectivity of that channel? */
@@ -80,23 +80,31 @@ typedef struct {
 
 static void pf_destroy(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol) {
   pick_first_lb_policy *p = (pick_first_lb_policy *)pol;
-  size_t i;
   GPR_ASSERT(p->pending_picks == NULL);
-  for (i = 0; i < p->num_subchannels; i++) {
-    GRPC_SUBCHANNEL_UNREF(exec_ctx, p->subchannels[i], "pick_first");
+  for (size_t i = 0; i < p->num_subchannels; i++) {
+    GRPC_SUBCHANNEL_UNREF(exec_ctx, p->subchannels[i], "pick_first_destroy");
   }
   if (p->selected != NULL) {
-    GRPC_CONNECTED_SUBCHANNEL_UNREF(exec_ctx, p->selected, "picked_first");
+    GRPC_CONNECTED_SUBCHANNEL_UNREF(exec_ctx, p->selected,
+                                    "picked_first_destroy");
   }
   grpc_connectivity_state_destroy(exec_ctx, &p->state_tracker);
+  if (p->pending_update_args != NULL) {
+    grpc_channel_args_destroy(exec_ctx, p->pending_update_args->args);
+    gpr_free(p->pending_update_args);
+  }
   gpr_free(p->subchannels);
+  gpr_free(p->new_subchannels);
   gpr_free(p);
+  if (GRPC_TRACER_ON(grpc_lb_pick_first_trace)) {
+    gpr_log(GPR_DEBUG, "Pick First %p destroyed.", (void *)p);
+  }
 }
 
 static void pf_shutdown_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol) {
   pick_first_lb_policy *p = (pick_first_lb_policy *)pol;
   pending_pick *pp;
-  p->shutdown = 1;
+  p->shutdown = true;
   pp = p->pending_picks;
   p->pending_picks = NULL;
   grpc_connectivity_state_set(
@@ -106,7 +114,7 @@ static void pf_shutdown_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol) {
   if (p->selected != NULL) {
     grpc_connected_subchannel_notify_on_state_change(
         exec_ctx, p->selected, NULL, NULL, &p->connectivity_changed);
-  } else if (p->num_subchannels > 0) {
+  } else if (p->num_subchannels > 0 && p->started_picking) {
     grpc_subchannel_notify_on_state_change(
         exec_ctx, p->subchannels[p->checking_subchannel], NULL, NULL,
         &p->connectivity_changed);
@@ -114,7 +122,7 @@ static void pf_shutdown_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol) {
   while (pp != NULL) {
     pending_pick *next = pp->next;
     *pp->target = NULL;
-    grpc_closure_sched(exec_ctx, pp->on_complete, GRPC_ERROR_NONE);
+    GRPC_CLOSURE_SCHED(exec_ctx, pp->on_complete, GRPC_ERROR_NONE);
     gpr_free(pp);
     pp = next;
   }
@@ -131,7 +139,7 @@ static void pf_cancel_pick_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol,
     pending_pick *next = pp->next;
     if (pp->target == target) {
       *target = NULL;
-      grpc_closure_sched(exec_ctx, pp->on_complete,
+      GRPC_CLOSURE_SCHED(exec_ctx, pp->on_complete,
                          GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
                              "Pick Cancelled", &error, 1));
       gpr_free(pp);
@@ -156,7 +164,7 @@ static void pf_cancel_picks_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol,
     pending_pick *next = pp->next;
     if ((pp->initial_metadata_flags & initial_metadata_flags_mask) ==
         initial_metadata_flags_eq) {
-      grpc_closure_sched(exec_ctx, pp->on_complete,
+      GRPC_CLOSURE_SCHED(exec_ctx, pp->on_complete,
                          GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
                              "Pick Cancelled", &error, 1));
       gpr_free(pp);
@@ -169,21 +177,25 @@ static void pf_cancel_picks_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol,
   GRPC_ERROR_UNREF(error);
 }
 
-static void start_picking(grpc_exec_ctx *exec_ctx, pick_first_lb_policy *p) {
-  p->started_picking = 1;
-  p->checking_subchannel = 0;
-  p->checking_connectivity = GRPC_CHANNEL_IDLE;
-  GRPC_LB_POLICY_WEAK_REF(&p->base, "pick_first_connectivity");
-  grpc_subchannel_notify_on_state_change(
-      exec_ctx, p->subchannels[p->checking_subchannel],
-      p->base.interested_parties, &p->checking_connectivity,
-      &p->connectivity_changed);
+static void start_picking_locked(grpc_exec_ctx *exec_ctx,
+                                 pick_first_lb_policy *p) {
+  p->started_picking = true;
+  if (p->subchannels != NULL) {
+    GPR_ASSERT(p->num_subchannels > 0);
+    p->checking_subchannel = 0;
+    p->checking_connectivity = GRPC_CHANNEL_IDLE;
+    GRPC_LB_POLICY_WEAK_REF(&p->base, "pick_first_connectivity");
+    grpc_subchannel_notify_on_state_change(
+        exec_ctx, p->subchannels[p->checking_subchannel],
+        p->base.interested_parties, &p->checking_connectivity,
+        &p->connectivity_changed);
+  }
 }
 
 static void pf_exit_idle_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol) {
   pick_first_lb_policy *p = (pick_first_lb_policy *)pol;
   if (!p->started_picking) {
-    start_picking(exec_ctx, p);
+    start_picking_locked(exec_ctx, p);
   }
 }
 
@@ -203,7 +215,7 @@ static int pf_pick_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol,
 
   /* No subchannel selected yet, so try again */
   if (!p->started_picking) {
-    start_picking(exec_ctx, p);
+    start_picking_locked(exec_ctx, p);
   }
   pp = gpr_malloc(sizeof(*pp));
   pp->next = p->pending_picks;
@@ -216,30 +228,314 @@ static int pf_pick_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol,
 
 static void destroy_subchannels_locked(grpc_exec_ctx *exec_ctx,
                                        pick_first_lb_policy *p) {
-  size_t i;
   size_t num_subchannels = p->num_subchannels;
-  grpc_subchannel **subchannels;
+  grpc_subchannel **subchannels = p->subchannels;
 
-  subchannels = p->subchannels;
   p->num_subchannels = 0;
   p->subchannels = NULL;
   GRPC_LB_POLICY_WEAK_UNREF(exec_ctx, &p->base, "destroy_subchannels");
 
-  for (i = 0; i < num_subchannels; i++) {
+  for (size_t i = 0; i < num_subchannels; i++) {
     GRPC_SUBCHANNEL_UNREF(exec_ctx, subchannels[i], "pick_first");
   }
-
   gpr_free(subchannels);
 }
 
+static grpc_connectivity_state pf_check_connectivity_locked(
+    grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol, grpc_error **error) {
+  pick_first_lb_policy *p = (pick_first_lb_policy *)pol;
+  return grpc_connectivity_state_get(&p->state_tracker, error);
+}
+
+static void pf_notify_on_state_change_locked(grpc_exec_ctx *exec_ctx,
+                                             grpc_lb_policy *pol,
+                                             grpc_connectivity_state *current,
+                                             grpc_closure *notify) {
+  pick_first_lb_policy *p = (pick_first_lb_policy *)pol;
+  grpc_connectivity_state_notify_on_state_change(exec_ctx, &p->state_tracker,
+                                                 current, notify);
+}
+
+static void pf_ping_one_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol,
+                               grpc_closure *closure) {
+  pick_first_lb_policy *p = (pick_first_lb_policy *)pol;
+  if (p->selected) {
+    grpc_connected_subchannel_ping(exec_ctx, p->selected, closure);
+  } else {
+    GRPC_CLOSURE_SCHED(exec_ctx, closure,
+                       GRPC_ERROR_CREATE_FROM_STATIC_STRING("Not connected"));
+  }
+}
+
+/* unsubscribe all subchannels */
+static void stop_connectivity_watchers(grpc_exec_ctx *exec_ctx,
+                                       pick_first_lb_policy *p) {
+  if (p->num_subchannels > 0) {
+    GPR_ASSERT(p->selected == NULL);
+    if (GRPC_TRACER_ON(grpc_lb_pick_first_trace)) {
+      gpr_log(GPR_DEBUG, "Pick First %p unsubscribing from subchannel %p",
+              (void *)p, (void *)p->subchannels[p->checking_subchannel]);
+    }
+    grpc_subchannel_notify_on_state_change(
+        exec_ctx, p->subchannels[p->checking_subchannel], NULL, NULL,
+        &p->connectivity_changed);
+    p->updating_subchannels = true;
+  } else if (p->selected != NULL) {
+    if (GRPC_TRACER_ON(grpc_lb_pick_first_trace)) {
+      gpr_log(GPR_DEBUG,
+              "Pick First %p unsubscribing from selected subchannel %p",
+              (void *)p, (void *)p->selected);
+    }
+    grpc_connected_subchannel_notify_on_state_change(
+        exec_ctx, p->selected, NULL, NULL, &p->connectivity_changed);
+    p->updating_selected = true;
+  }
+}
+
+/* true upon success */
+static void pf_update_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *policy,
+                             const grpc_lb_policy_args *args) {
+  pick_first_lb_policy *p = (pick_first_lb_policy *)policy;
+  /* Find the number of backend addresses. We ignore balancer
+   * addresses, since we don't know how to handle them. */
+  const grpc_arg *arg =
+      grpc_channel_args_find(args->args, GRPC_ARG_LB_ADDRESSES);
+  if (arg == NULL || arg->type != GRPC_ARG_POINTER) {
+    if (p->subchannels == NULL) {
+      // If we don't have a current subchannel list, go into TRANSIENT FAILURE.
+      grpc_connectivity_state_set(
+          exec_ctx, &p->state_tracker, GRPC_CHANNEL_TRANSIENT_FAILURE,
+          GRPC_ERROR_CREATE_FROM_STATIC_STRING("Missing update in args"),
+          "pf_update_missing");
+    } else {
+      // otherwise, keep using the current subchannel list (ignore this update).
+      gpr_log(GPR_ERROR,
+              "No valid LB addresses channel arg for Pick First %p update, "
+              "ignoring.",
+              (void *)p);
+    }
+    return;
+  }
+  const grpc_lb_addresses *addresses = arg->value.pointer.p;
+  size_t num_addrs = 0;
+  for (size_t i = 0; i < addresses->num_addresses; i++) {
+    if (!addresses->addresses[i].is_balancer) ++num_addrs;
+  }
+  if (num_addrs == 0) {
+    // Empty update. Unsubscribe from all current subchannels and put the
+    // channel in TRANSIENT_FAILURE.
+    grpc_connectivity_state_set(
+        exec_ctx, &p->state_tracker, GRPC_CHANNEL_TRANSIENT_FAILURE,
+        GRPC_ERROR_CREATE_FROM_STATIC_STRING("Empty update"),
+        "pf_update_empty");
+    stop_connectivity_watchers(exec_ctx, p);
+    return;
+  }
+  if (GRPC_TRACER_ON(grpc_lb_pick_first_trace)) {
+    gpr_log(GPR_INFO, "Pick First %p received update with %lu addresses",
+            (void *)p, (unsigned long)num_addrs);
+  }
+  grpc_subchannel_args *sc_args = gpr_zalloc(sizeof(*sc_args) * num_addrs);
+  /* We remove the following keys in order for subchannel keys belonging to
+   * subchannels point to the same address to match. */
+  static const char *keys_to_remove[] = {GRPC_ARG_SUBCHANNEL_ADDRESS,
+                                         GRPC_ARG_LB_ADDRESSES};
+  size_t sc_args_count = 0;
+
+  /* Create list of subchannel args for new addresses in \a args. */
+  for (size_t i = 0; i < addresses->num_addresses; i++) {
+    if (addresses->addresses[i].is_balancer) continue;
+    if (addresses->addresses[i].user_data != NULL) {
+      gpr_log(GPR_ERROR,
+              "This LB policy doesn't support user data. It will be ignored");
+    }
+    grpc_arg addr_arg =
+        grpc_create_subchannel_address_arg(&addresses->addresses[i].address);
+    grpc_channel_args *new_args = grpc_channel_args_copy_and_add_and_remove(
+        args->args, keys_to_remove, GPR_ARRAY_SIZE(keys_to_remove), &addr_arg,
+        1);
+    gpr_free(addr_arg.value.string);
+    sc_args[sc_args_count++].args = new_args;
+  }
+
+  /* Check if p->selected is amongst them. If so, we are done. */
+  if (p->selected != NULL) {
+    GPR_ASSERT(p->selected_key != NULL);
+    for (size_t i = 0; i < sc_args_count; i++) {
+      grpc_subchannel_key *ith_sc_key = grpc_subchannel_key_create(&sc_args[i]);
+      const bool found_selected =
+          grpc_subchannel_key_compare(p->selected_key, ith_sc_key) == 0;
+      grpc_subchannel_key_destroy(exec_ctx, ith_sc_key);
+      if (found_selected) {
+        // The currently selected subchannel is in the update: we are done.
+        if (GRPC_TRACER_ON(grpc_lb_pick_first_trace)) {
+          gpr_log(GPR_INFO,
+                  "Pick First %p found already selected subchannel %p amongst "
+                  "updates. Update done.",
+                  (void *)p, (void *)p->selected);
+        }
+        for (size_t j = 0; j < sc_args_count; j++) {
+          grpc_channel_args_destroy(exec_ctx,
+                                    (grpc_channel_args *)sc_args[j].args);
+        }
+        gpr_free(sc_args);
+        return;
+      }
+    }
+  }
+  // We only check for already running updates here because if the previous
+  // steps were successful, the update can be considered done without any
+  // interference (ie, no callbacks were scheduled).
+  if (p->updating_selected || p->updating_subchannels) {
+    if (GRPC_TRACER_ON(grpc_lb_pick_first_trace)) {
+      gpr_log(GPR_INFO,
+              "Update already in progress for pick first %p. Deferring update.",
+              (void *)p);
+    }
+    if (p->pending_update_args != NULL) {
+      grpc_channel_args_destroy(exec_ctx, p->pending_update_args->args);
+      gpr_free(p->pending_update_args);
+    }
+    p->pending_update_args = gpr_zalloc(sizeof(*p->pending_update_args));
+    p->pending_update_args->client_channel_factory =
+        args->client_channel_factory;
+    p->pending_update_args->args = grpc_channel_args_copy(args->args);
+    p->pending_update_args->combiner = args->combiner;
+    return;
+  }
+  /* Create the subchannels for the new subchannel args/addresses. */
+  grpc_subchannel **new_subchannels =
+      gpr_zalloc(sizeof(*new_subchannels) * sc_args_count);
+  size_t num_new_subchannels = 0;
+  for (size_t i = 0; i < sc_args_count; i++) {
+    grpc_subchannel *subchannel = grpc_client_channel_factory_create_subchannel(
+        exec_ctx, args->client_channel_factory, &sc_args[i]);
+    if (GRPC_TRACER_ON(grpc_lb_pick_first_trace)) {
+      char *address_uri =
+          grpc_sockaddr_to_uri(&addresses->addresses[i].address);
+      gpr_log(GPR_INFO,
+              "Pick First %p created subchannel %p for address uri %s",
+              (void *)p, (void *)subchannel, address_uri);
+      gpr_free(address_uri);
+    }
+    grpc_channel_args_destroy(exec_ctx, (grpc_channel_args *)sc_args[i].args);
+    if (subchannel != NULL) new_subchannels[num_new_subchannels++] = subchannel;
+  }
+  gpr_free(sc_args);
+  if (num_new_subchannels == 0) {
+    gpr_free(new_subchannels);
+    // Empty update. Unsubscribe from all current subchannels and put the
+    // channel in TRANSIENT_FAILURE.
+    grpc_connectivity_state_set(
+        exec_ctx, &p->state_tracker, GRPC_CHANNEL_TRANSIENT_FAILURE,
+        GRPC_ERROR_CREATE_FROM_STATIC_STRING("No valid addresses in update"),
+        "pf_update_no_valid_addresses");
+    stop_connectivity_watchers(exec_ctx, p);
+    return;
+  }
+
+  /* Destroy the current subchannels. Repurpose pf_shutdown/destroy. */
+  stop_connectivity_watchers(exec_ctx, p);
+
+  /* Save new subchannels. The switch over will happen in
+   * pf_connectivity_changed_locked */
+  if (p->updating_selected || p->updating_subchannels) {
+    p->num_new_subchannels = num_new_subchannels;
+    p->new_subchannels = new_subchannels;
+  } else { /* nothing is updating. Get things moving from here */
+    p->num_subchannels = num_new_subchannels;
+    p->subchannels = new_subchannels;
+    p->new_subchannels = NULL;
+    p->num_new_subchannels = 0;
+    if (p->started_picking) {
+      p->checking_subchannel = 0;
+      p->checking_connectivity = GRPC_CHANNEL_IDLE;
+      grpc_subchannel_notify_on_state_change(
+          exec_ctx, p->subchannels[p->checking_subchannel],
+          p->base.interested_parties, &p->checking_connectivity,
+          &p->connectivity_changed);
+    }
+  }
+}
+
 static void pf_connectivity_changed_locked(grpc_exec_ctx *exec_ctx, void *arg,
                                            grpc_error *error) {
   pick_first_lb_policy *p = arg;
   grpc_subchannel *selected_subchannel;
   pending_pick *pp;
 
+  if (GRPC_TRACER_ON(grpc_lb_pick_first_trace)) {
+    gpr_log(
+        GPR_DEBUG,
+        "Pick First %p connectivity changed. Updating selected: %d; Updating "
+        "subchannels: %d; Checking %lu index (%lu total); State: %d; ",
+        (void *)p, p->updating_selected, p->updating_subchannels,
+        (unsigned long)p->checking_subchannel,
+        (unsigned long)p->num_subchannels, p->checking_connectivity);
+  }
+  bool restart = false;
+  if (p->updating_selected && error != GRPC_ERROR_NONE) {
+    /* Captured the unsubscription for p->selected */
+    GPR_ASSERT(p->selected != NULL);
+    GRPC_CONNECTED_SUBCHANNEL_UNREF(exec_ctx, p->selected,
+                                    "pf_update_connectivity");
+    if (GRPC_TRACER_ON(grpc_lb_pick_first_trace)) {
+      gpr_log(GPR_DEBUG, "Pick First %p unreffing selected subchannel %p",
+              (void *)p, (void *)p->selected);
+    }
+    p->updating_selected = false;
+    if (p->num_new_subchannels == 0) {
+      p->selected = NULL;
+      return;
+    }
+    restart = true;
+  }
+  if (p->updating_subchannels && error != GRPC_ERROR_NONE) {
+    /* Captured the unsubscription for the checking subchannel */
+    GPR_ASSERT(p->selected == NULL);
+    for (size_t i = 0; i < p->num_subchannels; i++) {
+      GRPC_SUBCHANNEL_UNREF(exec_ctx, p->subchannels[i],
+                            "pf_update_connectivity");
+      if (GRPC_TRACER_ON(grpc_lb_pick_first_trace)) {
+        gpr_log(GPR_DEBUG, "Pick First %p unreffing subchannel %p", (void *)p,
+                (void *)p->subchannels[i]);
+      }
+    }
+    gpr_free(p->subchannels);
+    p->subchannels = NULL;
+    p->num_subchannels = 0;
+    p->updating_subchannels = false;
+    if (p->num_new_subchannels == 0) return;
+    restart = true;
+  }
+  if (restart) {
+    p->selected = NULL;
+    p->selected_key = NULL;
+    GPR_ASSERT(p->new_subchannels != NULL);
+    GPR_ASSERT(p->num_new_subchannels > 0);
+    p->num_subchannels = p->num_new_subchannels;
+    p->subchannels = p->new_subchannels;
+    p->num_new_subchannels = 0;
+    p->new_subchannels = NULL;
+    if (p->started_picking) {
+      /* If we were picking, continue to do so over the new subchannels,
+       * starting from the 0th index. */
+      p->checking_subchannel = 0;
+      p->checking_connectivity = GRPC_CHANNEL_IDLE;
+      /* reuses the weak ref from start_picking_locked */
+      grpc_subchannel_notify_on_state_change(
+          exec_ctx, p->subchannels[p->checking_subchannel],
+          p->base.interested_parties, &p->checking_connectivity,
+          &p->connectivity_changed);
+    }
+    if (p->pending_update_args != NULL) {
+      const grpc_lb_policy_args *args = p->pending_update_args;
+      p->pending_update_args = NULL;
+      pf_update_locked(exec_ctx, &p->base, args);
+    }
+    return;
+  }
   GRPC_ERROR_REF(error);
-
   if (p->shutdown) {
     GRPC_LB_POLICY_WEAK_UNREF(exec_ctx, &p->base, "pick_first_connectivity");
     GRPC_ERROR_UNREF(error);
@@ -272,6 +568,13 @@ static void pf_connectivity_changed_locked(grpc_exec_ctx *exec_ctx, void *arg,
         p->selected = GRPC_CONNECTED_SUBCHANNEL_REF(
             grpc_subchannel_get_connected_subchannel(selected_subchannel),
             "picked_first");
+
+        if (GRPC_TRACER_ON(grpc_lb_pick_first_trace)) {
+          gpr_log(GPR_INFO,
+                  "Pick First %p selected subchannel %p (connected %p)",
+                  (void *)p, (void *)selected_subchannel, (void *)p->selected);
+        }
+        p->selected_key = grpc_subchannel_get_key(selected_subchannel);
         /* drop the pick list: we are connected now */
         GRPC_LB_POLICY_WEAK_REF(&p->base, "destroy_subchannels");
         destroy_subchannels_locked(exec_ctx, p);
@@ -279,7 +582,12 @@ static void pf_connectivity_changed_locked(grpc_exec_ctx *exec_ctx, void *arg,
         while ((pp = p->pending_picks)) {
           p->pending_picks = pp->next;
           *pp->target = GRPC_CONNECTED_SUBCHANNEL_REF(p->selected, "picked");
-          grpc_closure_sched(exec_ctx, pp->on_complete, GRPC_ERROR_NONE);
+          if (GRPC_TRACER_ON(grpc_lb_pick_first_trace)) {
+            gpr_log(GPR_INFO,
+                    "Servicing pending pick with selected subchannel %p",
+                    (void *)p->selected);
+          }
+          GRPC_CLOSURE_SCHED(exec_ctx, pp->on_complete, GRPC_ERROR_NONE);
           gpr_free(pp);
         }
         grpc_connected_subchannel_notify_on_state_change(
@@ -290,7 +598,8 @@ static void pf_connectivity_changed_locked(grpc_exec_ctx *exec_ctx, void *arg,
         p->checking_subchannel =
             (p->checking_subchannel + 1) % p->num_subchannels;
         if (p->checking_subchannel == 0) {
-          /* only trigger transient failure when we've tried all alternatives */
+          /* only trigger transient failure when we've tried all alternatives
+           */
           grpc_connectivity_state_set(
               exec_ctx, &p->state_tracker, GRPC_CHANNEL_TRANSIENT_FAILURE,
               GRPC_ERROR_REF(error), "connecting_transient_failure");
@@ -332,7 +641,7 @@ static void pf_connectivity_changed_locked(grpc_exec_ctx *exec_ctx, void *arg,
           while ((pp = p->pending_picks)) {
             p->pending_picks = pp->next;
             *pp->target = NULL;
-            grpc_closure_sched(exec_ctx, pp->on_complete, GRPC_ERROR_NONE);
+            GRPC_CLOSURE_SCHED(exec_ctx, pp->on_complete, GRPC_ERROR_NONE);
             gpr_free(pp);
           }
           GRPC_LB_POLICY_WEAK_UNREF(exec_ctx, &p->base,
@@ -353,32 +662,6 @@ static void pf_connectivity_changed_locked(grpc_exec_ctx *exec_ctx, void *arg,
   GRPC_ERROR_UNREF(error);
 }
 
-static grpc_connectivity_state pf_check_connectivity_locked(
-    grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol, grpc_error **error) {
-  pick_first_lb_policy *p = (pick_first_lb_policy *)pol;
-  return grpc_connectivity_state_get(&p->state_tracker, error);
-}
-
-static void pf_notify_on_state_change_locked(grpc_exec_ctx *exec_ctx,
-                                             grpc_lb_policy *pol,
-                                             grpc_connectivity_state *current,
-                                             grpc_closure *notify) {
-  pick_first_lb_policy *p = (pick_first_lb_policy *)pol;
-  grpc_connectivity_state_notify_on_state_change(exec_ctx, &p->state_tracker,
-                                                 current, notify);
-}
-
-static void pf_ping_one_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol,
-                               grpc_closure *closure) {
-  pick_first_lb_policy *p = (pick_first_lb_policy *)pol;
-  if (p->selected) {
-    grpc_connected_subchannel_ping(exec_ctx, p->selected, closure);
-  } else {
-    grpc_closure_sched(exec_ctx, closure,
-                       GRPC_ERROR_CREATE_FROM_STATIC_STRING("Not connected"));
-  }
-}
-
 static const grpc_lb_policy_vtable pick_first_lb_policy_vtable = {
     pf_destroy,
     pf_shutdown_locked,
@@ -388,7 +671,8 @@ static const grpc_lb_policy_vtable pick_first_lb_policy_vtable = {
     pf_ping_one_locked,
     pf_exit_idle_locked,
     pf_check_connectivity_locked,
-    pf_notify_on_state_change_locked};
+    pf_notify_on_state_change_locked,
+    pf_update_locked};
 
 static void pick_first_factory_ref(grpc_lb_policy_factory *factory) {}
 
@@ -398,62 +682,14 @@ static grpc_lb_policy *create_pick_first(grpc_exec_ctx *exec_ctx,
                                          grpc_lb_policy_factory *factory,
                                          grpc_lb_policy_args *args) {
   GPR_ASSERT(args->client_channel_factory != NULL);
-
-  /* Find the number of backend addresses. We ignore balancer
-   * addresses, since we don't know how to handle them. */
-  const grpc_arg *arg =
-      grpc_channel_args_find(args->args, GRPC_ARG_LB_ADDRESSES);
-  if (arg == NULL || arg->type != GRPC_ARG_POINTER) {
-    return NULL;
-  }
-  grpc_lb_addresses *addresses = arg->value.pointer.p;
-  size_t num_addrs = 0;
-  for (size_t i = 0; i < addresses->num_addresses; i++) {
-    if (!addresses->addresses[i].is_balancer) ++num_addrs;
-  }
-  if (num_addrs == 0) return NULL;
-
   pick_first_lb_policy *p = gpr_zalloc(sizeof(*p));
-
-  p->subchannels = gpr_zalloc(sizeof(grpc_subchannel *) * num_addrs);
-  grpc_subchannel_args sc_args;
-  size_t subchannel_idx = 0;
-  for (size_t i = 0; i < addresses->num_addresses; i++) {
-    /* Skip balancer addresses, since we only know how to handle backends. */
-    if (addresses->addresses[i].is_balancer) continue;
-
-    if (addresses->addresses[i].user_data != NULL) {
-      gpr_log(GPR_ERROR,
-              "This LB policy doesn't support user data. It will be ignored");
-    }
-
-    static const char *keys_to_remove[] = {GRPC_ARG_SUBCHANNEL_ADDRESS};
-    memset(&sc_args, 0, sizeof(grpc_subchannel_args));
-    grpc_arg addr_arg =
-        grpc_create_subchannel_address_arg(&addresses->addresses[i].address);
-    grpc_channel_args *new_args = grpc_channel_args_copy_and_add_and_remove(
-        args->args, keys_to_remove, GPR_ARRAY_SIZE(keys_to_remove), &addr_arg,
-        1);
-    gpr_free(addr_arg.value.string);
-    sc_args.args = new_args;
-    grpc_subchannel *subchannel = grpc_client_channel_factory_create_subchannel(
-        exec_ctx, args->client_channel_factory, &sc_args);
-    grpc_channel_args_destroy(exec_ctx, new_args);
-
-    if (subchannel != NULL) {
-      p->subchannels[subchannel_idx++] = subchannel;
-    }
+  if (GRPC_TRACER_ON(grpc_lb_pick_first_trace)) {
+    gpr_log(GPR_DEBUG, "Pick First %p created.", (void *)p);
   }
-  if (subchannel_idx == 0) {
-    gpr_free(p->subchannels);
-    gpr_free(p);
-    return NULL;
-  }
-  p->num_subchannels = subchannel_idx;
-
+  pf_update_locked(exec_ctx, &p->base, args);
   grpc_lb_policy_init(&p->base, &pick_first_lb_policy_vtable, args->combiner);
-  grpc_closure_init(&p->connectivity_changed, pf_connectivity_changed_locked, p,
-                    grpc_combiner_scheduler(args->combiner, false));
+  GRPC_CLOSURE_INIT(&p->connectivity_changed, pf_connectivity_changed_locked, p,
+                    grpc_combiner_scheduler(args->combiner));
   return &p->base;
 }
 
@@ -472,6 +708,7 @@ static grpc_lb_policy_factory *pick_first_lb_factory_create() {
 
 void grpc_lb_policy_pick_first_init() {
   grpc_register_lb_policy(pick_first_lb_factory_create());
+  grpc_register_tracer(&grpc_lb_pick_first_trace);
 }
 
 void grpc_lb_policy_pick_first_shutdown() {}
diff --git a/src/core/ext/filters/client_channel/lb_policy/round_robin/round_robin.c b/src/core/ext/filters/client_channel/lb_policy/round_robin/round_robin.c
index 6e7f410635..341763a4d7 100644
--- a/src/core/ext/filters/client_channel/lb_policy/round_robin/round_robin.c
+++ b/src/core/ext/filters/client_channel/lb_policy/round_robin/round_robin.c
@@ -1,63 +1,28 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
 /** Round Robin Policy.
  *
- * This policy keeps:
- * - A circular list of ready (connected) subchannels, the *readylist*. An empty
- *   readylist consists solely of its root (dummy) node.
- * - A pointer to the last element picked from the readylist, the *lastpick*.
- *   Initially set to point to the readylist's root.
- *
- * Behavior:
- * - When a subchannel connects, it's *prepended* to the readylist's root node.
- *   Ie, if readylist = A <-> B <-> ROOT <-> C
- *                      ^                    ^
- *                      |____________________|
- *   and subchannel D becomes connected, the addition of D to the readylist
- *   results in  readylist = A <-> B <-> D <-> ROOT <-> C
- *                           ^                          ^
- *                           |__________________________|
- * - When a subchannel disconnects, it's removed from the readylist. If the
- *   subchannel being removed was the most recently picked, the *lastpick*
- *   pointer moves to the removed node's previous element. Note that if the
- *   readylist only had one element, this is still legal, as the lastpick would
- *   point to the dummy root node, for an empty readylist.
- * - Upon picking, *lastpick* is updated to point to the returned (connected)
- *   subchannel. Note that it's possible that the selected subchannel becomes
- *   disconnected in the interim between the selection and the actual usage of
- *   the subchannel by the caller.
- */
+ * Before every pick, the \a get_next_ready_subchannel_index_locked function
+ * returns the p->subchannel_list->subchannels index for next subchannel,
+ * respecting the relative
+ * order of the addresses provided upon creation or updates. Note however that
+ * updates will start picking from the beginning of the updated list. */
 
 #include <string.h>
 
@@ -72,9 +37,8 @@
 #include "src/core/lib/transport/connectivity_state.h"
 #include "src/core/lib/transport/static_metadata.h"
 
-typedef struct round_robin_lb_policy round_robin_lb_policy;
-
-grpc_tracer_flag grpc_lb_round_robin_trace = GRPC_TRACER_INITIALIZER(false);
+grpc_tracer_flag grpc_lb_round_robin_trace =
+    GRPC_TRACER_INITIALIZER(false, "round_robin");
 
 /** List of entities waiting for a pick.
  *
@@ -99,26 +63,41 @@ typedef struct pending_pick {
   grpc_closure *on_complete;
 } pending_pick;
 
-/** List of subchannels in a connectivity READY state */
-typedef struct ready_list {
-  grpc_subchannel *subchannel;
-  /* references namesake entry in subchannel_data */
-  void *user_data;
-  struct ready_list *next;
-  struct ready_list *prev;
-} ready_list;
+typedef struct rr_subchannel_list rr_subchannel_list;
+typedef struct round_robin_lb_policy {
+  /** base policy: must be first */
+  grpc_lb_policy base;
+
+  rr_subchannel_list *subchannel_list;
+
+  /** have we started picking? */
+  bool started_picking;
+  /** are we shutting down? */
+  bool shutdown;
+  /** List of picks that are waiting on connectivity */
+  pending_pick *pending_picks;
+
+  /** our connectivity state tracker */
+  grpc_connectivity_state_tracker state_tracker;
+
+  /** Index into subchannels for last pick. */
+  size_t last_ready_subchannel_index;
+
+  /** Latest version of the subchannel list.
+   * Subchannel connectivity callbacks will only promote updated subchannel
+   * lists if they equal \a latest_pending_subchannel_list. In other words,
+   * racing callbacks that reference outdated subchannel lists won't perform any
+   * update. */
+  rr_subchannel_list *latest_pending_subchannel_list;
+} round_robin_lb_policy;
 
 typedef struct {
-  /** index within policy->subchannels */
-  size_t index;
-  /** backpointer to owning policy */
-  round_robin_lb_policy *policy;
+  /** backpointer to owning subchannel list */
+  rr_subchannel_list *subchannel_list;
   /** subchannel itself */
   grpc_subchannel *subchannel;
   /** notification that connectivity has changed on subchannel */
   grpc_closure connectivity_changed_closure;
-  /** this subchannels current position in subchannel->ready_list */
-  ready_list *ready_list_node;
   /** last observed connectivity. Not updated by
    * \a grpc_subchannel_notify_on_state_change. Used to determine the previous
    * state while processing the new state in \a rr_connectivity_changed */
@@ -126,201 +105,225 @@ typedef struct {
   /** current connectivity state. Updated by \a
    * grpc_subchannel_notify_on_state_change */
   grpc_connectivity_state curr_connectivity_state;
+  /** connectivity state to be updated by the watcher, not guarded by
+   * the combiner.  Will be moved to curr_connectivity_state inside of
+   * the combiner by rr_connectivity_changed_locked(). */
+  grpc_connectivity_state pending_connectivity_state_unsafe;
   /** the subchannel's target user data */
   void *user_data;
   /** vtable to operate over \a user_data */
   const grpc_lb_user_data_vtable *user_data_vtable;
 } subchannel_data;
 
-struct round_robin_lb_policy {
-  /** base policy: must be first */
-  grpc_lb_policy base;
-
-  /** total number of addresses received at creation time */
-  size_t num_addresses;
+struct rr_subchannel_list {
+  /** backpointer to owning policy */
+  round_robin_lb_policy *policy;
 
   /** all our subchannels */
   size_t num_subchannels;
-  subchannel_data **subchannels;
+  subchannel_data *subchannels;
 
-  /** how many subchannels are in TRANSIENT_FAILURE */
+  /** how many subchannels are in state READY */
+  size_t num_ready;
+  /** how many subchannels are in state TRANSIENT_FAILURE */
   size_t num_transient_failures;
-  /** how many subchannels are IDLE */
+  /** how many subchannels are in state SHUTDOWN */
+  size_t num_shutdown;
+  /** how many subchannels are in state IDLE */
   size_t num_idle;
 
-  /** have we started picking? */
-  int started_picking;
-  /** are we shutting down? */
-  int shutdown;
-  /** List of picks that are waiting on connectivity */
-  pending_pick *pending_picks;
+  /** There will be one ref for each entry in subchannels for which there is a
+   * pending connectivity state watcher callback. */
+  gpr_refcount refcount;
 
-  /** our connectivity state tracker */
-  grpc_connectivity_state_tracker state_tracker;
-
-  /** (Dummy) root of the doubly linked list containing READY subchannels */
-  ready_list ready_list;
-  /** Last pick from the ready list. */
-  ready_list *ready_list_last_pick;
+  /** Is this list shutting down? This may be true due to the shutdown of the
+   * policy itself or because a newer update has arrived while this one hadn't
+   * finished processing. */
+  bool shutting_down;
 };
 
-/** Returns the next subchannel from the connected list or NULL if the list is
- * empty.
- *
- * Note that this function does *not* advance p->ready_list_last_pick. Use \a
- * advance_last_picked_locked() for that. */
-static ready_list *peek_next_connected_locked(const round_robin_lb_policy *p) {
-  ready_list *selected;
-  selected = p->ready_list_last_pick->next;
-
-  while (selected != NULL) {
-    if (selected == &p->ready_list) {
-      GPR_ASSERT(selected->subchannel == NULL);
-      /* skip dummy root */
-      selected = selected->next;
-    } else {
-      GPR_ASSERT(selected->subchannel != NULL);
-      return selected;
-    }
+static rr_subchannel_list *rr_subchannel_list_create(round_robin_lb_policy *p,
+                                                     size_t num_subchannels) {
+  rr_subchannel_list *subchannel_list = gpr_zalloc(sizeof(*subchannel_list));
+  subchannel_list->policy = p;
+  subchannel_list->subchannels =
+      gpr_zalloc(sizeof(subchannel_data) * num_subchannels);
+  subchannel_list->num_subchannels = num_subchannels;
+  gpr_ref_init(&subchannel_list->refcount, 1);
+  if (GRPC_TRACER_ON(grpc_lb_round_robin_trace)) {
+    gpr_log(GPR_INFO, "[RR %p] Created subchannel list %p for %lu subchannels",
+            (void *)p, (void *)subchannel_list, (unsigned long)num_subchannels);
   }
-  return NULL;
+  return subchannel_list;
 }
 
-/** Advance the \a ready_list picking head. */
-static void advance_last_picked_locked(round_robin_lb_policy *p) {
-  if (p->ready_list_last_pick->next != NULL) { /* non-empty list */
-    p->ready_list_last_pick = p->ready_list_last_pick->next;
-    if (p->ready_list_last_pick == &p->ready_list) {
-      /* skip dummy root */
-      p->ready_list_last_pick = p->ready_list_last_pick->next;
+static void rr_subchannel_list_destroy(grpc_exec_ctx *exec_ctx,
+                                       rr_subchannel_list *subchannel_list) {
+  GPR_ASSERT(subchannel_list->shutting_down);
+  if (GRPC_TRACER_ON(grpc_lb_round_robin_trace)) {
+    gpr_log(GPR_INFO, "[RR %p] Destroying subchannel_list %p",
+            (void *)subchannel_list->policy, (void *)subchannel_list);
+  }
+  for (size_t i = 0; i < subchannel_list->num_subchannels; i++) {
+    subchannel_data *sd = &subchannel_list->subchannels[i];
+    if (sd->subchannel != NULL) {
+      GRPC_SUBCHANNEL_UNREF(exec_ctx, sd->subchannel,
+                            "rr_subchannel_list_destroy");
+    }
+    sd->subchannel = NULL;
+    if (sd->user_data != NULL) {
+      GPR_ASSERT(sd->user_data_vtable != NULL);
+      sd->user_data_vtable->destroy(exec_ctx, sd->user_data);
+      sd->user_data = NULL;
     }
-  } else { /* should be an empty list */
-    GPR_ASSERT(p->ready_list_last_pick == &p->ready_list);
   }
+  gpr_free(subchannel_list->subchannels);
+  gpr_free(subchannel_list);
+}
 
+static void rr_subchannel_list_ref(rr_subchannel_list *subchannel_list,
+                                   const char *reason) {
+  gpr_ref_non_zero(&subchannel_list->refcount);
   if (GRPC_TRACER_ON(grpc_lb_round_robin_trace)) {
-    gpr_log(GPR_DEBUG,
-            "[READYLIST, RR: %p] ADVANCED LAST PICK. NOW AT NODE %p (SC %p, "
-            "CSC %p)",
-            (void *)p, (void *)p->ready_list_last_pick,
-            (void *)p->ready_list_last_pick->subchannel,
-            (void *)grpc_subchannel_get_connected_subchannel(
-                p->ready_list_last_pick->subchannel));
+    const gpr_atm count = gpr_atm_acq_load(&subchannel_list->refcount.count);
+    gpr_log(GPR_INFO, "[RR %p] subchannel_list %p REF %lu->%lu (%s)",
+            (void *)subchannel_list->policy, (void *)subchannel_list,
+            (unsigned long)(count - 1), (unsigned long)count, reason);
   }
 }
 
-/** Prepends (relative to the root at p->ready_list) the connected subchannel \a
- * csc to the list of ready subchannels. */
-static ready_list *add_connected_sc_locked(round_robin_lb_policy *p,
-                                           subchannel_data *sd) {
-  ready_list *new_elem = gpr_zalloc(sizeof(ready_list));
-  new_elem->subchannel = sd->subchannel;
-  new_elem->user_data = sd->user_data;
-  if (p->ready_list.prev == NULL) {
-    /* first element */
-    new_elem->next = &p->ready_list;
-    new_elem->prev = &p->ready_list;
-    p->ready_list.next = new_elem;
-    p->ready_list.prev = new_elem;
-  } else {
-    new_elem->next = &p->ready_list;
-    new_elem->prev = p->ready_list.prev;
-    p->ready_list.prev->next = new_elem;
-    p->ready_list.prev = new_elem;
-  }
+static void rr_subchannel_list_unref(grpc_exec_ctx *exec_ctx,
+                                     rr_subchannel_list *subchannel_list,
+                                     const char *reason) {
+  const bool done = gpr_unref(&subchannel_list->refcount);
   if (GRPC_TRACER_ON(grpc_lb_round_robin_trace)) {
-    gpr_log(GPR_DEBUG, "[READYLIST] ADDING NODE %p (Conn. SC %p)",
-            (void *)new_elem, (void *)sd->subchannel);
+    const gpr_atm count = gpr_atm_acq_load(&subchannel_list->refcount.count);
+    gpr_log(GPR_INFO, "[RR %p] subchannel_list %p UNREF %lu->%lu (%s)",
+            (void *)subchannel_list->policy, (void *)subchannel_list,
+            (unsigned long)(count + 1), (unsigned long)count, reason);
+  }
+  if (done) {
+    rr_subchannel_list_destroy(exec_ctx, subchannel_list);
   }
-  return new_elem;
 }
 
-/** Removes \a node from the list of connected subchannels */
-static void remove_disconnected_sc_locked(round_robin_lb_policy *p,
-                                          ready_list *node) {
-  if (node == NULL) {
-    return;
+/** Mark \a subchannel_list as discarded. Unsubscribes all its subchannels. The
+ * watcher's callback will ultimately unref \a subchannel_list.  */
+static void rr_subchannel_list_shutdown_and_unref(
+    grpc_exec_ctx *exec_ctx, rr_subchannel_list *subchannel_list,
+    const char *reason) {
+  GPR_ASSERT(!subchannel_list->shutting_down);
+  if (GRPC_TRACER_ON(grpc_lb_round_robin_trace)) {
+    gpr_log(GPR_DEBUG, "[RR %p] Shutting down subchannel_list %p (%s)",
+            (void *)subchannel_list->policy, (void *)subchannel_list, reason);
   }
-  if (node == p->ready_list_last_pick) {
-    p->ready_list_last_pick = p->ready_list_last_pick->prev;
+  GPR_ASSERT(!subchannel_list->shutting_down);
+  subchannel_list->shutting_down = true;
+  for (size_t i = 0; i < subchannel_list->num_subchannels; i++) {
+    subchannel_data *sd = &subchannel_list->subchannels[i];
+    if (sd->subchannel != NULL) {  // if subchannel isn't shutdown, unsubscribe.
+      if (GRPC_TRACER_ON(grpc_lb_round_robin_trace)) {
+        gpr_log(
+            GPR_DEBUG,
+            "[RR %p] Unsubscribing from subchannel %p as part of shutting down "
+            "subchannel_list %p",
+            (void *)subchannel_list->policy, (void *)sd->subchannel,
+            (void *)subchannel_list);
+      }
+      grpc_subchannel_notify_on_state_change(exec_ctx, sd->subchannel, NULL,
+                                             NULL,
+                                             &sd->connectivity_changed_closure);
+    }
   }
+  rr_subchannel_list_unref(exec_ctx, subchannel_list, reason);
+}
 
-  /* removing last item */
-  if (node->next == &p->ready_list && node->prev == &p->ready_list) {
-    GPR_ASSERT(p->ready_list.next == node);
-    GPR_ASSERT(p->ready_list.prev == node);
-    p->ready_list.next = NULL;
-    p->ready_list.prev = NULL;
-  } else {
-    node->prev->next = node->next;
-    node->next->prev = node->prev;
+/** Returns the index into p->subchannel_list->subchannels of the next
+ * subchannel in READY state, or p->subchannel_list->num_subchannels if no
+ * subchannel is READY.
+ *
+ * Note that this function does *not* update p->last_ready_subchannel_index.
+ * The caller must do that if it returns a pick. */
+static size_t get_next_ready_subchannel_index_locked(
+    const round_robin_lb_policy *p) {
+  GPR_ASSERT(p->subchannel_list != NULL);
+  if (GRPC_TRACER_ON(grpc_lb_round_robin_trace)) {
+    gpr_log(GPR_INFO,
+            "[RR %p] getting next ready subchannel (out of %lu), "
+            "last_ready_subchannel_index=%lu",
+            (void *)p, (unsigned long)p->subchannel_list->num_subchannels,
+            (unsigned long)p->last_ready_subchannel_index);
+  }
+  for (size_t i = 0; i < p->subchannel_list->num_subchannels; ++i) {
+    const size_t index = (i + p->last_ready_subchannel_index + 1) %
+                         p->subchannel_list->num_subchannels;
+    if (GRPC_TRACER_ON(grpc_lb_round_robin_trace)) {
+      gpr_log(
+          GPR_DEBUG,
+          "[RR %p] checking subchannel %p, subchannel_list %p, index %lu: "
+          "state=%s",
+          (void *)p, (void *)p->subchannel_list->subchannels[index].subchannel,
+          (void *)p->subchannel_list, (unsigned long)index,
+          grpc_connectivity_state_name(
+              p->subchannel_list->subchannels[index].curr_connectivity_state));
+    }
+    if (p->subchannel_list->subchannels[index].curr_connectivity_state ==
+        GRPC_CHANNEL_READY) {
+      if (GRPC_TRACER_ON(grpc_lb_round_robin_trace)) {
+        gpr_log(GPR_DEBUG,
+                "[RR %p] found next ready subchannel (%p) at index %lu of "
+                "subchannel_list %p",
+                (void *)p,
+                (void *)p->subchannel_list->subchannels[index].subchannel,
+                (unsigned long)index, (void *)p->subchannel_list);
+      }
+      return index;
+    }
   }
-
   if (GRPC_TRACER_ON(grpc_lb_round_robin_trace)) {
-    gpr_log(GPR_DEBUG, "[READYLIST] REMOVED NODE %p (SC %p)", (void *)node,
-            (void *)node->subchannel);
+    gpr_log(GPR_DEBUG, "[RR %p] no subchannels in ready state", (void *)p);
   }
-
-  node->next = NULL;
-  node->prev = NULL;
-  node->subchannel = NULL;
-
-  gpr_free(node);
+  return p->subchannel_list->num_subchannels;
 }
 
-static bool is_ready_list_empty(round_robin_lb_policy *p) {
-  return p->ready_list.prev == NULL;
+// Sets p->last_ready_subchannel_index to last_ready_index.
+static void update_last_ready_subchannel_index_locked(round_robin_lb_policy *p,
+                                                      size_t last_ready_index) {
+  GPR_ASSERT(last_ready_index < p->subchannel_list->num_subchannels);
+  p->last_ready_subchannel_index = last_ready_index;
+  if (GRPC_TRACER_ON(grpc_lb_round_robin_trace)) {
+    gpr_log(
+        GPR_DEBUG,
+        "[RR %p] setting last_ready_subchannel_index=%lu (SC %p, CSC %p)",
+        (void *)p, (unsigned long)last_ready_index,
+        (void *)p->subchannel_list->subchannels[last_ready_index].subchannel,
+        (void *)grpc_subchannel_get_connected_subchannel(
+            p->subchannel_list->subchannels[last_ready_index].subchannel));
+  }
 }
 
 static void rr_destroy(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol) {
   round_robin_lb_policy *p = (round_robin_lb_policy *)pol;
-  ready_list *elem;
-
   if (GRPC_TRACER_ON(grpc_lb_round_robin_trace)) {
-    gpr_log(GPR_DEBUG, "Destroying Round Robin policy at %p", (void *)pol);
-  }
-
-  for (size_t i = 0; i < p->num_subchannels; i++) {
-    subchannel_data *sd = p->subchannels[i];
-    GRPC_SUBCHANNEL_UNREF(exec_ctx, sd->subchannel, "rr_destroy");
-    if (sd->user_data != NULL) {
-      GPR_ASSERT(sd->user_data_vtable != NULL);
-      sd->user_data_vtable->destroy(exec_ctx, sd->user_data);
-    }
-    gpr_free(sd);
+    gpr_log(GPR_DEBUG, "[RR %p] Destroying Round Robin policy at %p",
+            (void *)pol, (void *)pol);
   }
-
   grpc_connectivity_state_destroy(exec_ctx, &p->state_tracker);
-  gpr_free(p->subchannels);
-
-  elem = p->ready_list.next;
-  while (elem != NULL && elem != &p->ready_list) {
-    ready_list *tmp;
-    tmp = elem->next;
-    elem->next = NULL;
-    elem->prev = NULL;
-    elem->subchannel = NULL;
-    gpr_free(elem);
-    elem = tmp;
-  }
-
   gpr_free(p);
 }
 
 static void rr_shutdown_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol) {
   round_robin_lb_policy *p = (round_robin_lb_policy *)pol;
-  pending_pick *pp;
-  size_t i;
-
   if (GRPC_TRACER_ON(grpc_lb_round_robin_trace)) {
-    gpr_log(GPR_DEBUG, "Shutting down Round Robin policy at %p", (void *)pol);
+    gpr_log(GPR_DEBUG, "[RR %p] Shutting down Round Robin policy at %p",
+            (void *)pol, (void *)pol);
   }
-
-  p->shutdown = 1;
+  p->shutdown = true;
+  pending_pick *pp;
   while ((pp = p->pending_picks)) {
     p->pending_picks = pp->next;
     *pp->target = NULL;
-    grpc_closure_sched(
+    GRPC_CLOSURE_SCHED(
         exec_ctx, pp->on_complete,
         GRPC_ERROR_CREATE_FROM_STATIC_STRING("Channel Shutdown"));
     gpr_free(pp);
@@ -328,10 +331,17 @@ static void rr_shutdown_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol) {
   grpc_connectivity_state_set(
       exec_ctx, &p->state_tracker, GRPC_CHANNEL_SHUTDOWN,
       GRPC_ERROR_CREATE_FROM_STATIC_STRING("Channel Shutdown"), "rr_shutdown");
-  for (i = 0; i < p->num_subchannels; i++) {
-    subchannel_data *sd = p->subchannels[i];
-    grpc_subchannel_notify_on_state_change(exec_ctx, sd->subchannel, NULL, NULL,
-                                           &sd->connectivity_changed_closure);
+  const bool latest_is_current =
+      p->subchannel_list == p->latest_pending_subchannel_list;
+  rr_subchannel_list_shutdown_and_unref(exec_ctx, p->subchannel_list,
+                                        "sl_shutdown_rr_shutdown");
+  p->subchannel_list = NULL;
+  if (!latest_is_current && p->latest_pending_subchannel_list != NULL &&
+      !p->latest_pending_subchannel_list->shutting_down) {
+    rr_subchannel_list_shutdown_and_unref(exec_ctx,
+                                          p->latest_pending_subchannel_list,
+                                          "sl_shutdown_pending_rr_shutdown");
+    p->latest_pending_subchannel_list = NULL;
   }
 }
 
@@ -339,14 +349,13 @@ static void rr_cancel_pick_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol,
                                   grpc_connected_subchannel **target,
                                   grpc_error *error) {
   round_robin_lb_policy *p = (round_robin_lb_policy *)pol;
-  pending_pick *pp;
-  pp = p->pending_picks;
+  pending_pick *pp = p->pending_picks;
   p->pending_picks = NULL;
   while (pp != NULL) {
     pending_pick *next = pp->next;
     if (pp->target == target) {
       *target = NULL;
-      grpc_closure_sched(exec_ctx, pp->on_complete,
+      GRPC_CLOSURE_SCHED(exec_ctx, pp->on_complete,
                          GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
                              "Pick cancelled", &error, 1));
       gpr_free(pp);
@@ -364,15 +373,14 @@ static void rr_cancel_picks_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol,
                                    uint32_t initial_metadata_flags_eq,
                                    grpc_error *error) {
   round_robin_lb_policy *p = (round_robin_lb_policy *)pol;
-  pending_pick *pp;
-  pp = p->pending_picks;
+  pending_pick *pp = p->pending_picks;
   p->pending_picks = NULL;
   while (pp != NULL) {
     pending_pick *next = pp->next;
     if ((pp->initial_metadata_flags & initial_metadata_flags_mask) ==
         initial_metadata_flags_eq) {
       *pp->target = NULL;
-      grpc_closure_sched(exec_ctx, pp->on_complete,
+      GRPC_CLOSURE_SCHED(exec_ctx, pp->on_complete,
                          GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
                              "Pick cancelled", &error, 1));
       gpr_free(pp);
@@ -387,21 +395,15 @@ static void rr_cancel_picks_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol,
 
 static void start_picking_locked(grpc_exec_ctx *exec_ctx,
                                  round_robin_lb_policy *p) {
-  size_t i;
-  p->started_picking = 1;
-
-  for (i = 0; i < p->num_subchannels; i++) {
-    subchannel_data *sd = p->subchannels[i];
-    /* use some sentinel value outside of the range of grpc_connectivity_state
-     * to signal an undefined previous state. We won't be referring to this
-     * value again and it'll be overwritten after the first call to
-     * rr_connectivity_changed */
-    sd->prev_connectivity_state = GRPC_CHANNEL_INIT;
-    sd->curr_connectivity_state = GRPC_CHANNEL_IDLE;
-    GRPC_LB_POLICY_WEAK_REF(&p->base, "rr_connectivity");
+  p->started_picking = true;
+  for (size_t i = 0; i < p->subchannel_list->num_subchannels; i++) {
+    subchannel_data *sd = &p->subchannel_list->subchannels[i];
+    GRPC_LB_POLICY_WEAK_REF(&p->base, "start_picking_locked");
+    rr_subchannel_list_ref(sd->subchannel_list, "started_picking");
     grpc_subchannel_notify_on_state_change(
         exec_ctx, sd->subchannel, p->base.interested_parties,
-        &sd->curr_connectivity_state, &sd->connectivity_changed_closure);
+        &sd->pending_connectivity_state_unsafe,
+        &sd->connectivity_changed_closure);
   }
 }
 
@@ -418,65 +420,79 @@ static int rr_pick_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol,
                           grpc_call_context_element *context, void **user_data,
                           grpc_closure *on_complete) {
   round_robin_lb_policy *p = (round_robin_lb_policy *)pol;
-  pending_pick *pp;
-  ready_list *selected;
-
   if (GRPC_TRACER_ON(grpc_lb_round_robin_trace)) {
-    gpr_log(GPR_INFO, "Round Robin %p trying to pick", (void *)pol);
+    gpr_log(GPR_INFO, "[RR %p] Trying to pick", (void *)pol);
   }
-
-  if ((selected = peek_next_connected_locked(p))) {
-    /* readily available, report right away */
-    *target = GRPC_CONNECTED_SUBCHANNEL_REF(
-        grpc_subchannel_get_connected_subchannel(selected->subchannel),
-        "rr_picked");
-
-    if (user_data != NULL) {
-      *user_data = selected->user_data;
-    }
-    if (GRPC_TRACER_ON(grpc_lb_round_robin_trace)) {
-      gpr_log(GPR_DEBUG,
-              "[RR PICK] TARGET <-- CONNECTED SUBCHANNEL %p (NODE %p)",
-              (void *)*target, (void *)selected);
-    }
-    /* only advance the last picked pointer if the selection was used */
-    advance_last_picked_locked(p);
-    return 1;
-  } else {
-    /* no pick currently available. Save for later in list of pending picks */
-    if (!p->started_picking) {
-      start_picking_locked(exec_ctx, p);
+  if (p->subchannel_list != NULL) {
+    const size_t next_ready_index = get_next_ready_subchannel_index_locked(p);
+    if (next_ready_index < p->subchannel_list->num_subchannels) {
+      /* readily available, report right away */
+      subchannel_data *sd = &p->subchannel_list->subchannels[next_ready_index];
+      *target = GRPC_CONNECTED_SUBCHANNEL_REF(
+          grpc_subchannel_get_connected_subchannel(sd->subchannel),
+          "rr_picked");
+      if (user_data != NULL) {
+        *user_data = sd->user_data;
+      }
+      if (GRPC_TRACER_ON(grpc_lb_round_robin_trace)) {
+        gpr_log(
+            GPR_DEBUG,
+            "[RR %p] Picked target <-- Subchannel %p (connected %p) (sl %p, "
+            "index %lu)",
+            (void *)p, (void *)sd->subchannel, (void *)*target,
+            (void *)sd->subchannel_list, (unsigned long)next_ready_index);
+      }
+      /* only advance the last picked pointer if the selection was used */
+      update_last_ready_subchannel_index_locked(p, next_ready_index);
+      return 1;
     }
-    pp = gpr_malloc(sizeof(*pp));
-    pp->next = p->pending_picks;
-    pp->target = target;
-    pp->on_complete = on_complete;
-    pp->initial_metadata_flags = pick_args->initial_metadata_flags;
-    pp->user_data = user_data;
-    p->pending_picks = pp;
-    return 0;
   }
+  /* no pick currently available. Save for later in list of pending picks */
+  if (!p->started_picking) {
+    start_picking_locked(exec_ctx, p);
+  }
+  pending_pick *pp = gpr_malloc(sizeof(*pp));
+  pp->next = p->pending_picks;
+  pp->target = target;
+  pp->on_complete = on_complete;
+  pp->initial_metadata_flags = pick_args->initial_metadata_flags;
+  pp->user_data = user_data;
+  p->pending_picks = pp;
+  return 0;
 }
 
-static void update_state_counters(subchannel_data *sd) {
-  round_robin_lb_policy *p = sd->policy;
-
-  /* update p->num_transient_failures (resp. p->num_idle): if the previous
-   * state was TRANSIENT_FAILURE (resp. IDLE), decrement
-   * p->num_transient_failures (resp. p->num_idle). */
-  if (sd->prev_connectivity_state == GRPC_CHANNEL_TRANSIENT_FAILURE) {
-    GPR_ASSERT(p->num_transient_failures > 0);
-    --p->num_transient_failures;
+static void update_state_counters_locked(subchannel_data *sd) {
+  rr_subchannel_list *subchannel_list = sd->subchannel_list;
+  if (sd->prev_connectivity_state == GRPC_CHANNEL_READY) {
+    GPR_ASSERT(subchannel_list->num_ready > 0);
+    --subchannel_list->num_ready;
+  } else if (sd->prev_connectivity_state == GRPC_CHANNEL_TRANSIENT_FAILURE) {
+    GPR_ASSERT(subchannel_list->num_transient_failures > 0);
+    --subchannel_list->num_transient_failures;
+  } else if (sd->prev_connectivity_state == GRPC_CHANNEL_SHUTDOWN) {
+    GPR_ASSERT(subchannel_list->num_shutdown > 0);
+    --subchannel_list->num_shutdown;
   } else if (sd->prev_connectivity_state == GRPC_CHANNEL_IDLE) {
-    GPR_ASSERT(p->num_idle > 0);
-    --p->num_idle;
+    GPR_ASSERT(subchannel_list->num_idle > 0);
+    --subchannel_list->num_idle;
+  }
+  if (sd->curr_connectivity_state == GRPC_CHANNEL_READY) {
+    ++subchannel_list->num_ready;
+  } else if (sd->curr_connectivity_state == GRPC_CHANNEL_TRANSIENT_FAILURE) {
+    ++subchannel_list->num_transient_failures;
+  } else if (sd->curr_connectivity_state == GRPC_CHANNEL_SHUTDOWN) {
+    ++subchannel_list->num_shutdown;
+  } else if (sd->curr_connectivity_state == GRPC_CHANNEL_IDLE) {
+    ++subchannel_list->num_idle;
   }
 }
 
-/* sd is the subchannel_data associted with the updated subchannel.
- * shutdown_error will only be used upon policy transition to TRANSIENT_FAILURE
- * or SHUTDOWN */
-static grpc_connectivity_state update_lb_connectivity_status(
+/** Sets the policy's connectivity status based on that of the passed-in \a sd
+ * (the subchannel_data associted with the updated subchannel) and the
+ * subchannel list \a sd belongs to (sd->subchannel_list). \a error will only be
+ * used upon policy transition to TRANSIENT_FAILURE or SHUTDOWN. Returns the
+ * connectivity status set. */
+static grpc_connectivity_state update_lb_connectivity_status_locked(
     grpc_exec_ctx *exec_ctx, subchannel_data *sd, grpc_error *error) {
   /* In priority order. The first rule to match terminates the search (ie, if we
    * are on rule n, all previous rules were unfulfilled).
@@ -488,76 +504,167 @@ static grpc_connectivity_state update_lb_connectivity_status(
    *    CHECK: sd->curr_connectivity_state == CONNECTING.
    *
    * 3) RULE: ALL subchannels are SHUTDOWN => policy is SHUTDOWN.
-   *    CHECK: p->num_subchannels = 0.
+   *    CHECK: p->subchannel_list->num_shutdown ==
+   *           p->subchannel_list->num_subchannels.
    *
    * 4) RULE: ALL subchannels are TRANSIENT_FAILURE => policy is
    *    TRANSIENT_FAILURE.
-   *    CHECK: p->num_transient_failures == p->num_subchannels.
+   *    CHECK: p->num_transient_failures == p->subchannel_list->num_subchannels.
    *
    * 5) RULE: ALL subchannels are IDLE => policy is IDLE.
-   *    CHECK: p->num_idle == p->num_subchannels.
+   *    CHECK: p->num_idle == p->subchannel_list->num_subchannels.
    */
-  round_robin_lb_policy *p = sd->policy;
-  if (!is_ready_list_empty(p)) { /* 1) READY */
+  grpc_connectivity_state new_state = sd->curr_connectivity_state;
+  rr_subchannel_list *subchannel_list = sd->subchannel_list;
+  round_robin_lb_policy *p = subchannel_list->policy;
+  if (subchannel_list->num_ready > 0) { /* 1) READY */
     grpc_connectivity_state_set(exec_ctx, &p->state_tracker, GRPC_CHANNEL_READY,
                                 GRPC_ERROR_NONE, "rr_ready");
-    return GRPC_CHANNEL_READY;
+    new_state = GRPC_CHANNEL_READY;
   } else if (sd->curr_connectivity_state ==
              GRPC_CHANNEL_CONNECTING) { /* 2) CONNECTING */
     grpc_connectivity_state_set(exec_ctx, &p->state_tracker,
                                 GRPC_CHANNEL_CONNECTING, GRPC_ERROR_NONE,
                                 "rr_connecting");
-    return GRPC_CHANNEL_CONNECTING;
-  } else if (p->num_subchannels == 0) { /* 3) SHUTDOWN */
+    new_state = GRPC_CHANNEL_CONNECTING;
+  } else if (p->subchannel_list->num_shutdown ==
+             p->subchannel_list->num_subchannels) { /* 3) SHUTDOWN */
     grpc_connectivity_state_set(exec_ctx, &p->state_tracker,
                                 GRPC_CHANNEL_SHUTDOWN, GRPC_ERROR_REF(error),
                                 "rr_shutdown");
-    return GRPC_CHANNEL_SHUTDOWN;
-  } else if (p->num_transient_failures ==
-             p->num_subchannels) { /* 4) TRANSIENT_FAILURE */
+    new_state = GRPC_CHANNEL_SHUTDOWN;
+  } else if (subchannel_list->num_transient_failures ==
+             p->subchannel_list->num_subchannels) { /* 4) TRANSIENT_FAILURE */
     grpc_connectivity_state_set(exec_ctx, &p->state_tracker,
                                 GRPC_CHANNEL_TRANSIENT_FAILURE,
                                 GRPC_ERROR_REF(error), "rr_transient_failure");
-    return GRPC_CHANNEL_TRANSIENT_FAILURE;
-  } else if (p->num_idle == p->num_subchannels) { /* 5) IDLE */
+    new_state = GRPC_CHANNEL_TRANSIENT_FAILURE;
+  } else if (subchannel_list->num_idle ==
+             p->subchannel_list->num_subchannels) { /* 5) IDLE */
     grpc_connectivity_state_set(exec_ctx, &p->state_tracker, GRPC_CHANNEL_IDLE,
                                 GRPC_ERROR_NONE, "rr_idle");
-    return GRPC_CHANNEL_IDLE;
+    new_state = GRPC_CHANNEL_IDLE;
   }
-  /* no change */
-  return sd->curr_connectivity_state;
+  GRPC_ERROR_UNREF(error);
+  return new_state;
 }
 
 static void rr_connectivity_changed_locked(grpc_exec_ctx *exec_ctx, void *arg,
                                            grpc_error *error) {
   subchannel_data *sd = arg;
-  round_robin_lb_policy *p = sd->policy;
-  pending_pick *pp;
-
-  GRPC_ERROR_REF(error);
-
+  round_robin_lb_policy *p = sd->subchannel_list->policy;
+  if (GRPC_TRACER_ON(grpc_lb_round_robin_trace)) {
+    gpr_log(
+        GPR_DEBUG,
+        "[RR %p] connectivity changed for subchannel %p, subchannel_list %p: "
+        "prev_state=%s new_state=%s p->shutdown=%d "
+        "sd->subchannel_list->shutting_down=%d error=%s",
+        (void *)p, (void *)sd->subchannel, (void *)sd->subchannel_list,
+        grpc_connectivity_state_name(sd->prev_connectivity_state),
+        grpc_connectivity_state_name(sd->pending_connectivity_state_unsafe),
+        p->shutdown, sd->subchannel_list->shutting_down,
+        grpc_error_string(error));
+  }
+  // If the policy is shutting down, unref and return.
   if (p->shutdown) {
-    GRPC_LB_POLICY_WEAK_UNREF(exec_ctx, &p->base, "rr_connectivity");
-    GRPC_ERROR_UNREF(error);
+    rr_subchannel_list_unref(exec_ctx, sd->subchannel_list,
+                             "pol_shutdown+started_picking");
+    GRPC_LB_POLICY_WEAK_UNREF(exec_ctx, &p->base, "pol_shutdown");
     return;
   }
-  switch (sd->curr_connectivity_state) {
-    case GRPC_CHANNEL_INIT:
-      GPR_UNREACHABLE_CODE(return );
-    case GRPC_CHANNEL_READY:
-      /* add the newly connected subchannel to the list of connected ones.
-       * Note that it goes to the "end of the line". */
-      sd->ready_list_node = add_connected_sc_locked(p, sd);
+  if (sd->subchannel_list->shutting_down && error == GRPC_ERROR_CANCELLED) {
+    // the subchannel list associated with sd has been discarded. This callback
+    // corresponds to the unsubscription. The unrefs correspond to the picking
+    // ref (start_picking_locked or update_started_picking).
+    rr_subchannel_list_unref(exec_ctx, sd->subchannel_list,
+                             "sl_shutdown+started_picking");
+    GRPC_LB_POLICY_WEAK_UNREF(exec_ctx, &p->base, "sl_shutdown+picking");
+    return;
+  }
+  // Dispose of outdated subchannel lists.
+  if (sd->subchannel_list != p->subchannel_list &&
+      sd->subchannel_list != p->latest_pending_subchannel_list) {
+    // sd belongs to an outdated subchannel_list: get rid of it.
+    rr_subchannel_list_shutdown_and_unref(exec_ctx, sd->subchannel_list,
+                                          "sl_outdated");
+    GRPC_LB_POLICY_WEAK_UNREF(exec_ctx, &p->base, "sl_outdated");
+    return;
+  }
+  // Now that we're inside the combiner, copy the pending connectivity
+  // state (which was set by the connectivity state watcher) to
+  // curr_connectivity_state, which is what we use inside of the combiner.
+  sd->curr_connectivity_state = sd->pending_connectivity_state_unsafe;
+  // Update state counters and determine new overall state.
+  update_state_counters_locked(sd);
+  sd->prev_connectivity_state = sd->curr_connectivity_state;
+  const grpc_connectivity_state new_policy_connectivity_state =
+      update_lb_connectivity_status_locked(exec_ctx, sd, GRPC_ERROR_REF(error));
+  // If the sd's new state is SHUTDOWN, unref the subchannel, and if the new
+  // policy's state is SHUTDOWN, clean up.
+  if (sd->curr_connectivity_state == GRPC_CHANNEL_SHUTDOWN) {
+    GRPC_SUBCHANNEL_UNREF(exec_ctx, sd->subchannel, "rr_subchannel_shutdown");
+    sd->subchannel = NULL;
+    if (sd->user_data != NULL) {
+      GPR_ASSERT(sd->user_data_vtable != NULL);
+      sd->user_data_vtable->destroy(exec_ctx, sd->user_data);
+      sd->user_data = NULL;
+    }
+    if (new_policy_connectivity_state == GRPC_CHANNEL_SHUTDOWN) {
+      // the policy is shutting down. Flush all the pending picks...
+      pending_pick *pp;
+      while ((pp = p->pending_picks)) {
+        p->pending_picks = pp->next;
+        *pp->target = NULL;
+        GRPC_CLOSURE_SCHED(exec_ctx, pp->on_complete, GRPC_ERROR_NONE);
+        gpr_free(pp);
+      }
+    }
+    rr_subchannel_list_unref(exec_ctx, sd->subchannel_list,
+                             "sd_shutdown+started_picking");
+    // unref the "rr_connectivity_update" weak ref from start_picking.
+    GRPC_LB_POLICY_WEAK_UNREF(exec_ctx, &p->base,
+                              "rr_connectivity_sd_shutdown");
+  } else {  // sd not in SHUTDOWN
+    if (sd->curr_connectivity_state == GRPC_CHANNEL_READY) {
+      if (sd->subchannel_list != p->subchannel_list) {
+        // promote sd->subchannel_list to p->subchannel_list.
+        // sd->subchannel_list must be equal to
+        // p->latest_pending_subchannel_list because we have already filtered
+        // for sds belonging to outdated subchannel lists.
+        GPR_ASSERT(sd->subchannel_list == p->latest_pending_subchannel_list);
+        GPR_ASSERT(!sd->subchannel_list->shutting_down);
+        if (GRPC_TRACER_ON(grpc_lb_round_robin_trace)) {
+          const unsigned long num_subchannels =
+              p->subchannel_list != NULL
+                  ? (unsigned long)p->subchannel_list->num_subchannels
+                  : 0;
+          gpr_log(GPR_DEBUG,
+                  "[RR %p] phasing out subchannel list %p (size %lu) in favor "
+                  "of %p (size %lu)",
+                  (void *)p, (void *)p->subchannel_list, num_subchannels,
+                  (void *)sd->subchannel_list, num_subchannels);
+        }
+        if (p->subchannel_list != NULL) {
+          // dispose of the current subchannel_list
+          rr_subchannel_list_shutdown_and_unref(exec_ctx, p->subchannel_list,
+                                                "sl_phase_out_shutdown");
+        }
+        p->subchannel_list = p->latest_pending_subchannel_list;
+        p->latest_pending_subchannel_list = NULL;
+      }
       /* at this point we know there's at least one suitable subchannel. Go
        * ahead and pick one and notify the pending suitors in
        * p->pending_picks. This preemtively replicates rr_pick()'s actions. */
-      ready_list *selected = peek_next_connected_locked(p);
-      GPR_ASSERT(selected != NULL);
+      const size_t next_ready_index = get_next_ready_subchannel_index_locked(p);
+      GPR_ASSERT(next_ready_index < p->subchannel_list->num_subchannels);
+      subchannel_data *selected =
+          &p->subchannel_list->subchannels[next_ready_index];
       if (p->pending_picks != NULL) {
-        /* if the selected subchannel is going to be used for the pending
-         * picks, update the last picked pointer */
-        advance_last_picked_locked(p);
+        // if the selected subchannel is going to be used for the pending
+        // picks, update the last picked pointer
+        update_last_ready_subchannel_index_locked(p, next_ready_index);
       }
+      pending_pick *pp;
       while ((pp = p->pending_picks)) {
         p->pending_picks = pp->next;
         *pp->target = GRPC_CONNECTED_SUBCHANNEL_REF(
@@ -568,72 +675,22 @@ static void rr_connectivity_changed_locked(grpc_exec_ctx *exec_ctx, void *arg,
         }
         if (GRPC_TRACER_ON(grpc_lb_round_robin_trace)) {
           gpr_log(GPR_DEBUG,
-                  "[RR CONN CHANGED] TARGET <-- SUBCHANNEL %p (NODE %p)",
-                  (void *)selected->subchannel, (void *)selected);
+                  "[RR %p] Fulfilling pending pick. Target <-- subchannel %p "
+                  "(subchannel_list %p, index %lu)",
+                  (void *)p, (void *)selected->subchannel,
+                  (void *)p->subchannel_list, (unsigned long)next_ready_index);
         }
-        grpc_closure_sched(exec_ctx, pp->on_complete, GRPC_ERROR_NONE);
+        GRPC_CLOSURE_SCHED(exec_ctx, pp->on_complete, GRPC_ERROR_NONE);
         gpr_free(pp);
       }
-      update_lb_connectivity_status(exec_ctx, sd, error);
-      sd->prev_connectivity_state = sd->curr_connectivity_state;
-      /* renew notification: reuses the "rr_connectivity" weak ref */
-      grpc_subchannel_notify_on_state_change(
-          exec_ctx, sd->subchannel, p->base.interested_parties,
-          &sd->curr_connectivity_state, &sd->connectivity_changed_closure);
-      break;
-    case GRPC_CHANNEL_IDLE:
-      ++p->num_idle;
-    /* fallthrough */
-    case GRPC_CHANNEL_CONNECTING:
-      update_state_counters(sd);
-      update_lb_connectivity_status(exec_ctx, sd, error);
-      sd->prev_connectivity_state = sd->curr_connectivity_state;
-      /* renew notification: reuses the "rr_connectivity" weak ref */
-      grpc_subchannel_notify_on_state_change(
-          exec_ctx, sd->subchannel, p->base.interested_parties,
-          &sd->curr_connectivity_state, &sd->connectivity_changed_closure);
-      break;
-    case GRPC_CHANNEL_TRANSIENT_FAILURE:
-      ++p->num_transient_failures;
-      /* remove from ready list if still present */
-      if (sd->ready_list_node != NULL) {
-        remove_disconnected_sc_locked(p, sd->ready_list_node);
-        sd->ready_list_node = NULL;
-      }
-      update_lb_connectivity_status(exec_ctx, sd, error);
-      sd->prev_connectivity_state = sd->curr_connectivity_state;
-      /* renew notification: reuses the "rr_connectivity" weak ref */
-      grpc_subchannel_notify_on_state_change(
-          exec_ctx, sd->subchannel, p->base.interested_parties,
-          &sd->curr_connectivity_state, &sd->connectivity_changed_closure);
-      break;
-    case GRPC_CHANNEL_SHUTDOWN:
-      update_state_counters(sd);
-      if (sd->ready_list_node != NULL) {
-        remove_disconnected_sc_locked(p, sd->ready_list_node);
-        sd->ready_list_node = NULL;
-      }
-      --p->num_subchannels;
-      GPR_SWAP(subchannel_data *, p->subchannels[sd->index],
-               p->subchannels[p->num_subchannels]);
-      GRPC_SUBCHANNEL_UNREF(exec_ctx, sd->subchannel, "rr_subchannel_shutdown");
-      p->subchannels[sd->index]->index = sd->index;
-      if (update_lb_connectivity_status(exec_ctx, sd, error) ==
-          GRPC_CHANNEL_SHUTDOWN) {
-        /* the policy is shutting down. Flush all the pending picks... */
-        while ((pp = p->pending_picks)) {
-          p->pending_picks = pp->next;
-          *pp->target = NULL;
-          grpc_closure_sched(exec_ctx, pp->on_complete, GRPC_ERROR_NONE);
-          gpr_free(pp);
-        }
-      }
-      gpr_free(sd);
-      /* unref the "rr_connectivity" weak ref from start_picking */
-      GRPC_LB_POLICY_WEAK_UNREF(exec_ctx, &p->base, "rr_connectivity");
-      break;
+    }
+    /* renew notification: reuses the "rr_connectivity_update" weak ref on the
+     * policy as well as the sd->subchannel_list ref. */
+    grpc_subchannel_notify_on_state_change(
+        exec_ctx, sd->subchannel, p->base.interested_parties,
+        &sd->pending_connectivity_state_unsafe,
+        &sd->connectivity_changed_closure);
   }
-  GRPC_ERROR_UNREF(error);
 }
 
 static grpc_connectivity_state rr_check_connectivity_locked(
@@ -654,66 +711,85 @@ static void rr_notify_on_state_change_locked(grpc_exec_ctx *exec_ctx,
 static void rr_ping_one_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol,
                                grpc_closure *closure) {
   round_robin_lb_policy *p = (round_robin_lb_policy *)pol;
-  ready_list *selected;
-  grpc_connected_subchannel *target;
-  if ((selected = peek_next_connected_locked(p))) {
-    target = GRPC_CONNECTED_SUBCHANNEL_REF(
+  const size_t next_ready_index = get_next_ready_subchannel_index_locked(p);
+  if (next_ready_index < p->subchannel_list->num_subchannels) {
+    subchannel_data *selected =
+        &p->subchannel_list->subchannels[next_ready_index];
+    grpc_connected_subchannel *target = GRPC_CONNECTED_SUBCHANNEL_REF(
         grpc_subchannel_get_connected_subchannel(selected->subchannel),
         "rr_picked");
     grpc_connected_subchannel_ping(exec_ctx, target, closure);
     GRPC_CONNECTED_SUBCHANNEL_UNREF(exec_ctx, target, "rr_picked");
   } else {
-    grpc_closure_sched(exec_ctx, closure, GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+    GRPC_CLOSURE_SCHED(exec_ctx, closure, GRPC_ERROR_CREATE_FROM_STATIC_STRING(
                                               "Round Robin not connected"));
   }
 }
 
-static const grpc_lb_policy_vtable round_robin_lb_policy_vtable = {
-    rr_destroy,
-    rr_shutdown_locked,
-    rr_pick_locked,
-    rr_cancel_pick_locked,
-    rr_cancel_picks_locked,
-    rr_ping_one_locked,
-    rr_exit_idle_locked,
-    rr_check_connectivity_locked,
-    rr_notify_on_state_change_locked};
-
-static void round_robin_factory_ref(grpc_lb_policy_factory *factory) {}
-
-static void round_robin_factory_unref(grpc_lb_policy_factory *factory) {}
-
-static grpc_lb_policy *round_robin_create(grpc_exec_ctx *exec_ctx,
-                                          grpc_lb_policy_factory *factory,
-                                          grpc_lb_policy_args *args) {
-  GPR_ASSERT(args->client_channel_factory != NULL);
-
-  /* Find the number of backend addresses. We ignore balancer
-   * addresses, since we don't know how to handle them. */
+static void rr_update_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *policy,
+                             const grpc_lb_policy_args *args) {
+  round_robin_lb_policy *p = (round_robin_lb_policy *)policy;
+  /* Find the number of backend addresses. We ignore balancer addresses, since
+   * we don't know how to handle them. */
   const grpc_arg *arg =
       grpc_channel_args_find(args->args, GRPC_ARG_LB_ADDRESSES);
   if (arg == NULL || arg->type != GRPC_ARG_POINTER) {
-    return NULL;
+    if (p->subchannel_list == NULL) {
+      // If we don't have a current subchannel list, go into TRANSIENT FAILURE.
+      grpc_connectivity_state_set(
+          exec_ctx, &p->state_tracker, GRPC_CHANNEL_TRANSIENT_FAILURE,
+          GRPC_ERROR_CREATE_FROM_STATIC_STRING("Missing update in args"),
+          "rr_update_missing");
+    } else {
+      // otherwise, keep using the current subchannel list (ignore this update).
+      gpr_log(GPR_ERROR,
+              "[RR %p] No valid LB addresses channel arg for update, ignoring.",
+              (void *)p);
+    }
+    return;
   }
   grpc_lb_addresses *addresses = arg->value.pointer.p;
   size_t num_addrs = 0;
   for (size_t i = 0; i < addresses->num_addresses; i++) {
     if (!addresses->addresses[i].is_balancer) ++num_addrs;
   }
-  if (num_addrs == 0) return NULL;
-
-  round_robin_lb_policy *p = gpr_zalloc(sizeof(*p));
-
-  p->num_addresses = num_addrs;
-  p->subchannels = gpr_zalloc(sizeof(*p->subchannels) * num_addrs);
-
+  if (num_addrs == 0) {
+    grpc_connectivity_state_set(
+        exec_ctx, &p->state_tracker, GRPC_CHANNEL_TRANSIENT_FAILURE,
+        GRPC_ERROR_CREATE_FROM_STATIC_STRING("Empty update"),
+        "rr_update_empty");
+    if (p->subchannel_list != NULL) {
+      rr_subchannel_list_shutdown_and_unref(exec_ctx, p->subchannel_list,
+                                            "sl_shutdown_empty_update");
+      p->subchannel_list = NULL;
+    }
+    return;
+  }
+  size_t subchannel_index = 0;
+  rr_subchannel_list *subchannel_list = rr_subchannel_list_create(p, num_addrs);
+  if (p->latest_pending_subchannel_list != NULL && p->started_picking) {
+    if (GRPC_TRACER_ON(grpc_lb_round_robin_trace)) {
+      gpr_log(GPR_DEBUG,
+              "[RR %p] Shutting down latest pending subchannel list %p, about "
+              "to be "
+              "replaced by newer latest %p",
+              (void *)p, (void *)p->latest_pending_subchannel_list,
+              (void *)subchannel_list);
+    }
+    rr_subchannel_list_shutdown_and_unref(
+        exec_ctx, p->latest_pending_subchannel_list, "sl_outdated_dont_smash");
+  }
+  p->latest_pending_subchannel_list = subchannel_list;
   grpc_subchannel_args sc_args;
-  size_t subchannel_idx = 0;
+  /* We need to remove the LB addresses in order to be able to compare the
+   * subchannel keys of subchannels from a different batch of addresses. */
+  static const char *keys_to_remove[] = {GRPC_ARG_SUBCHANNEL_ADDRESS,
+                                         GRPC_ARG_LB_ADDRESSES};
+  /* Create subchannels for addresses in the update. */
   for (size_t i = 0; i < addresses->num_addresses; i++) {
     /* Skip balancer addresses, since we only know how to handle backends. */
     if (addresses->addresses[i].is_balancer) continue;
-
-    static const char *keys_to_remove[] = {GRPC_ARG_SUBCHANNEL_ADDRESS};
+    GPR_ASSERT(i < num_addrs);
     memset(&sc_args, 0, sizeof(grpc_subchannel_args));
     grpc_arg addr_arg =
         grpc_create_subchannel_address_arg(&addresses->addresses[i].address);
@@ -727,50 +803,86 @@ static grpc_lb_policy *round_robin_create(grpc_exec_ctx *exec_ctx,
     if (GRPC_TRACER_ON(grpc_lb_round_robin_trace)) {
       char *address_uri =
           grpc_sockaddr_to_uri(&addresses->addresses[i].address);
-      gpr_log(GPR_DEBUG, "Created subchannel %p for address uri %s",
-              (void *)subchannel, address_uri);
+      gpr_log(
+          GPR_DEBUG,
+          "[RR %p] index %lu: Created subchannel %p for address uri %s into "
+          "subchannel_list %p",
+          (void *)p, (unsigned long)subchannel_index, (void *)subchannel,
+          address_uri, (void *)subchannel_list);
       gpr_free(address_uri);
     }
     grpc_channel_args_destroy(exec_ctx, new_args);
 
-    if (subchannel != NULL) {
-      subchannel_data *sd = gpr_zalloc(sizeof(*sd));
-      p->subchannels[subchannel_idx] = sd;
-      sd->policy = p;
-      sd->index = subchannel_idx;
-      sd->subchannel = subchannel;
-      sd->user_data_vtable = addresses->user_data_vtable;
-      if (sd->user_data_vtable != NULL) {
-        sd->user_data =
-            sd->user_data_vtable->copy(addresses->addresses[i].user_data);
-      }
-      ++subchannel_idx;
-      grpc_closure_init(&sd->connectivity_changed_closure,
-                        rr_connectivity_changed_locked, sd,
-                        grpc_combiner_scheduler(args->combiner, false));
+    subchannel_data *sd = &subchannel_list->subchannels[subchannel_index++];
+    sd->subchannel_list = subchannel_list;
+    sd->subchannel = subchannel;
+    GRPC_CLOSURE_INIT(&sd->connectivity_changed_closure,
+                      rr_connectivity_changed_locked, sd,
+                      grpc_combiner_scheduler(args->combiner));
+    /* use some sentinel value outside of the range of
+     * grpc_connectivity_state to signal an undefined previous state. We
+     * won't be referring to this value again and it'll be overwritten after
+     * the first call to rr_connectivity_changed_locked */
+    sd->prev_connectivity_state = GRPC_CHANNEL_INIT;
+    sd->curr_connectivity_state = GRPC_CHANNEL_IDLE;
+    sd->user_data_vtable = addresses->user_data_vtable;
+    if (sd->user_data_vtable != NULL) {
+      sd->user_data =
+          sd->user_data_vtable->copy(addresses->addresses[i].user_data);
+    }
+    if (p->started_picking) {
+      rr_subchannel_list_ref(sd->subchannel_list, "update_started_picking");
+      GRPC_LB_POLICY_WEAK_REF(&p->base, "rr_connectivity_update");
+      /* 2. Watch every new subchannel. A subchannel list becomes active the
+       * moment one of its subchannels is READY. At that moment, we swap
+       * p->subchannel_list for sd->subchannel_list, provided the subchannel
+       * list is still valid (ie, isn't shutting down) */
+      grpc_subchannel_notify_on_state_change(
+          exec_ctx, sd->subchannel, p->base.interested_parties,
+          &sd->pending_connectivity_state_unsafe,
+          &sd->connectivity_changed_closure);
     }
   }
-  if (subchannel_idx == 0) {
-    /* couldn't create any subchannel. Bail out */
-    gpr_free(p->subchannels);
-    gpr_free(p);
-    return NULL;
+  if (!p->started_picking) {
+    // The policy isn't picking yet. Save the update for later, disposing of
+    // previous version if any.
+    if (p->subchannel_list != NULL) {
+      rr_subchannel_list_shutdown_and_unref(exec_ctx, p->subchannel_list,
+                                            "rr_update_before_started_picking");
+    }
+    p->subchannel_list = subchannel_list;
+    p->latest_pending_subchannel_list = NULL;
   }
-  p->num_subchannels = subchannel_idx;
+}
 
-  /* The (dummy node) root of the ready list */
-  p->ready_list.subchannel = NULL;
-  p->ready_list.prev = NULL;
-  p->ready_list.next = NULL;
-  p->ready_list_last_pick = &p->ready_list;
+static const grpc_lb_policy_vtable round_robin_lb_policy_vtable = {
+    rr_destroy,
+    rr_shutdown_locked,
+    rr_pick_locked,
+    rr_cancel_pick_locked,
+    rr_cancel_picks_locked,
+    rr_ping_one_locked,
+    rr_exit_idle_locked,
+    rr_check_connectivity_locked,
+    rr_notify_on_state_change_locked,
+    rr_update_locked};
+
+static void round_robin_factory_ref(grpc_lb_policy_factory *factory) {}
+
+static void round_robin_factory_unref(grpc_lb_policy_factory *factory) {}
 
+static grpc_lb_policy *round_robin_create(grpc_exec_ctx *exec_ctx,
+                                          grpc_lb_policy_factory *factory,
+                                          grpc_lb_policy_args *args) {
+  GPR_ASSERT(args->client_channel_factory != NULL);
+  round_robin_lb_policy *p = gpr_zalloc(sizeof(*p));
+  rr_update_locked(exec_ctx, &p->base, args);
   grpc_lb_policy_init(&p->base, &round_robin_lb_policy_vtable, args->combiner);
   grpc_connectivity_state_init(&p->state_tracker, GRPC_CHANNEL_IDLE,
                                "round_robin");
-
   if (GRPC_TRACER_ON(grpc_lb_round_robin_trace)) {
-    gpr_log(GPR_DEBUG, "Created RR policy at %p with %lu subchannels",
-            (void *)p, (unsigned long)p->num_subchannels);
+    gpr_log(GPR_DEBUG, "[RR %p] Created with %lu subchannels", (void *)p,
+            (unsigned long)p->subchannel_list->num_subchannels);
   }
   return &p->base;
 }
@@ -790,7 +902,7 @@ static grpc_lb_policy_factory *round_robin_lb_factory_create() {
 
 void grpc_lb_policy_round_robin_init() {
   grpc_register_lb_policy(round_robin_lb_factory_create());
-  grpc_register_tracer("round_robin", &grpc_lb_round_robin_trace);
+  grpc_register_tracer(&grpc_lb_round_robin_trace);
 }
 
 void grpc_lb_policy_round_robin_shutdown() {}
diff --git a/src/core/ext/filters/client_channel/lb_policy_factory.c b/src/core/ext/filters/client_channel/lb_policy_factory.c
index 89b8bf8951..538d8d65ed 100644
--- a/src/core/ext/filters/client_channel/lb_policy_factory.c
+++ b/src/core/ext/filters/client_channel/lb_policy_factory.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -153,12 +138,8 @@ static const grpc_arg_pointer_vtable lb_addresses_arg_vtable = {
 
 grpc_arg grpc_lb_addresses_create_channel_arg(
     const grpc_lb_addresses* addresses) {
-  grpc_arg arg;
-  arg.type = GRPC_ARG_POINTER;
-  arg.key = GRPC_ARG_LB_ADDRESSES;
-  arg.value.pointer.p = (void*)addresses;
-  arg.value.pointer.vtable = &lb_addresses_arg_vtable;
-  return arg;
+  return grpc_channel_arg_pointer_create(
+      GRPC_ARG_LB_ADDRESSES, (void*)addresses, &lb_addresses_arg_vtable);
 }
 
 grpc_lb_addresses* grpc_lb_addresses_find_channel_arg(
diff --git a/src/core/ext/filters/client_channel/lb_policy_factory.h b/src/core/ext/filters/client_channel/lb_policy_factory.h
index 9d6c0fc139..9d9fb143df 100644
--- a/src/core/ext/filters/client_channel/lb_policy_factory.h
+++ b/src/core/ext/filters/client_channel/lb_policy_factory.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -118,11 +103,11 @@ grpc_lb_addresses *grpc_lb_addresses_find_channel_arg(
     const grpc_channel_args *channel_args);
 
 /** Arguments passed to LB policies. */
-typedef struct grpc_lb_policy_args {
+struct grpc_lb_policy_args {
   grpc_client_channel_factory *client_channel_factory;
   grpc_channel_args *args;
   grpc_combiner *combiner;
-} grpc_lb_policy_args;
+};
 
 struct grpc_lb_policy_factory_vtable {
   void (*ref)(grpc_lb_policy_factory *factory);
diff --git a/src/core/ext/filters/client_channel/lb_policy_registry.c b/src/core/ext/filters/client_channel/lb_policy_registry.c
index 1376673bca..f2460f8304 100644
--- a/src/core/ext/filters/client_channel/lb_policy_registry.c
+++ b/src/core/ext/filters/client_channel/lb_policy_registry.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/filters/client_channel/lb_policy_registry.h b/src/core/ext/filters/client_channel/lb_policy_registry.h
index dfdec1347f..f5995687cf 100644
--- a/src/core/ext/filters/client_channel/lb_policy_registry.h
+++ b/src/core/ext/filters/client_channel/lb_policy_registry.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/filters/client_channel/parse_address.c b/src/core/ext/filters/client_channel/parse_address.c
index edc6ce697d..2152b5a1e9 100644
--- a/src/core/ext/filters/client_channel/parse_address.c
+++ b/src/core/ext/filters/client_channel/parse_address.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -57,11 +42,11 @@ bool grpc_parse_unix(const grpc_uri *uri,
   struct sockaddr_un *un = (struct sockaddr_un *)resolved_addr->addr;
   const size_t maxlen = sizeof(un->sun_path);
   const size_t path_len = strnlen(uri->path, maxlen);
-  if (path_len == maxlen) return 0;
+  if (path_len == maxlen) return false;
   un->sun_family = AF_UNIX;
   strcpy(un->sun_path, uri->path);
   resolved_addr->len = sizeof(*un);
-  return 1;
+  return true;
 }
 
 #else /* GRPC_HAVE_UNIX_SOCKET */
@@ -73,74 +58,65 @@ bool grpc_parse_unix(const grpc_uri *uri,
 
 #endif /* GRPC_HAVE_UNIX_SOCKET */
 
-bool grpc_parse_ipv4(const grpc_uri *uri,
-                     grpc_resolved_address *resolved_addr) {
-  if (strcmp("ipv4", uri->scheme) != 0) {
-    gpr_log(GPR_ERROR, "Expected 'ipv4' scheme, got '%s'", uri->scheme);
-    return false;
-  }
-  const char *host_port = uri->path;
+bool grpc_parse_ipv4_hostport(const char *hostport, grpc_resolved_address *addr,
+                              bool log_errors) {
+  bool success = false;
+  // Split host and port.
   char *host;
   char *port;
-  int port_num;
-  bool result = false;
-  struct sockaddr_in *in = (struct sockaddr_in *)resolved_addr->addr;
-
-  if (*host_port == '/') ++host_port;
-  if (!gpr_split_host_port(host_port, &host, &port)) {
-    return false;
-  }
-
-  memset(resolved_addr, 0, sizeof(grpc_resolved_address));
-  resolved_addr->len = sizeof(struct sockaddr_in);
+  if (!gpr_split_host_port(hostport, &host, &port)) return false;
+  // Parse IP address.
+  memset(addr, 0, sizeof(*addr));
+  addr->len = sizeof(struct sockaddr_in);
+  struct sockaddr_in *in = (struct sockaddr_in *)addr->addr;
   in->sin_family = AF_INET;
   if (inet_pton(AF_INET, host, &in->sin_addr) == 0) {
-    gpr_log(GPR_ERROR, "invalid ipv4 address: '%s'", host);
+    if (log_errors) gpr_log(GPR_ERROR, "invalid ipv4 address: '%s'", host);
     goto done;
   }
-
-  if (port != NULL) {
-    if (sscanf(port, "%d", &port_num) != 1 || port_num < 0 ||
-        port_num > 65535) {
-      gpr_log(GPR_ERROR, "invalid ipv4 port: '%s'", port);
-      goto done;
-    }
-    in->sin_port = htons((uint16_t)port_num);
-  } else {
-    gpr_log(GPR_ERROR, "no port given for ipv4 scheme");
+  // Parse port.
+  if (port == NULL) {
+    if (log_errors) gpr_log(GPR_ERROR, "no port given for ipv4 scheme");
     goto done;
   }
-
-  result = true;
+  int port_num;
+  if (sscanf(port, "%d", &port_num) != 1 || port_num < 0 || port_num > 65535) {
+    if (log_errors) gpr_log(GPR_ERROR, "invalid ipv4 port: '%s'", port);
+    goto done;
+  }
+  in->sin_port = htons((uint16_t)port_num);
+  success = true;
 done:
   gpr_free(host);
   gpr_free(port);
-  return result;
+  return success;
 }
 
-bool grpc_parse_ipv6(const grpc_uri *uri,
+bool grpc_parse_ipv4(const grpc_uri *uri,
                      grpc_resolved_address *resolved_addr) {
-  if (strcmp("ipv6", uri->scheme) != 0) {
-    gpr_log(GPR_ERROR, "Expected 'ipv6' scheme, got '%s'", uri->scheme);
+  if (strcmp("ipv4", uri->scheme) != 0) {
+    gpr_log(GPR_ERROR, "Expected 'ipv4' scheme, got '%s'", uri->scheme);
     return false;
   }
   const char *host_port = uri->path;
-  char *host;
-  char *port;
-  int port_num;
-  int result = 0;
-  struct sockaddr_in6 *in6 = (struct sockaddr_in6 *)resolved_addr->addr;
-
   if (*host_port == '/') ++host_port;
-  if (!gpr_split_host_port(host_port, &host, &port)) {
-    return 0;
-  }
+  return grpc_parse_ipv4_hostport(host_port, resolved_addr,
+                                  true /* log_errors */);
+}
 
-  memset(in6, 0, sizeof(*in6));
-  resolved_addr->len = sizeof(*in6);
+bool grpc_parse_ipv6_hostport(const char *hostport, grpc_resolved_address *addr,
+                              bool log_errors) {
+  bool success = false;
+  // Split host and port.
+  char *host;
+  char *port;
+  if (!gpr_split_host_port(hostport, &host, &port)) return false;
+  // Parse IP address.
+  memset(addr, 0, sizeof(*addr));
+  addr->len = sizeof(struct sockaddr_in6);
+  struct sockaddr_in6 *in6 = (struct sockaddr_in6 *)addr->addr;
   in6->sin6_family = AF_INET6;
-
-  /* Handle the RFC6874 syntax for IPv6 zone identifiers. */
+  // Handle the RFC6874 syntax for IPv6 zone identifiers.
   char *host_end = (char *)gpr_memrchr(host, '%', strlen(host));
   if (host_end != NULL) {
     GPR_ASSERT(host_end >= host);
@@ -159,7 +135,7 @@ bool grpc_parse_ipv6(const grpc_uri *uri,
       gpr_log(GPR_ERROR, "invalid ipv6 scope id: '%s'", host_end + 1);
       goto done;
     }
-    // Handle "sin6_scope_id" being type "u_long". See grpc issue ##10027.
+    // Handle "sin6_scope_id" being type "u_long". See grpc issue #10027.
     in6->sin6_scope_id = sin6_scope_id;
   } else {
     if (inet_pton(AF_INET6, host, &in6->sin6_addr) == 0) {
@@ -167,24 +143,34 @@ bool grpc_parse_ipv6(const grpc_uri *uri,
       goto done;
     }
   }
-
-  if (port != NULL) {
-    if (sscanf(port, "%d", &port_num) != 1 || port_num < 0 ||
-        port_num > 65535) {
-      gpr_log(GPR_ERROR, "invalid ipv6 port: '%s'", port);
-      goto done;
-    }
-    in6->sin6_port = htons((uint16_t)port_num);
-  } else {
-    gpr_log(GPR_ERROR, "no port given for ipv6 scheme");
+  // Parse port.
+  if (port == NULL) {
+    if (log_errors) gpr_log(GPR_ERROR, "no port given for ipv6 scheme");
     goto done;
   }
-
-  result = 1;
+  int port_num;
+  if (sscanf(port, "%d", &port_num) != 1 || port_num < 0 || port_num > 65535) {
+    if (log_errors) gpr_log(GPR_ERROR, "invalid ipv6 port: '%s'", port);
+    goto done;
+  }
+  in6->sin6_port = htons((uint16_t)port_num);
+  success = true;
 done:
   gpr_free(host);
   gpr_free(port);
-  return result;
+  return success;
+}
+
+bool grpc_parse_ipv6(const grpc_uri *uri,
+                     grpc_resolved_address *resolved_addr) {
+  if (strcmp("ipv6", uri->scheme) != 0) {
+    gpr_log(GPR_ERROR, "Expected 'ipv6' scheme, got '%s'", uri->scheme);
+    return false;
+  }
+  const char *host_port = uri->path;
+  if (*host_port == '/') ++host_port;
+  return grpc_parse_ipv6_hostport(host_port, resolved_addr,
+                                  true /* log_errors */);
 }
 
 bool grpc_parse_uri(const grpc_uri *uri, grpc_resolved_address *resolved_addr) {
diff --git a/src/core/ext/filters/client_channel/parse_address.h b/src/core/ext/filters/client_channel/parse_address.h
index fa7ea33a00..c90a827da5 100644
--- a/src/core/ext/filters/client_channel/parse_address.h
+++ b/src/core/ext/filters/client_channel/parse_address.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -54,4 +39,10 @@ bool grpc_parse_ipv6(const grpc_uri *uri, grpc_resolved_address *resolved_addr);
 /** Populate \a resolved_addr from \a uri. Returns true upon success. */
 bool grpc_parse_uri(const grpc_uri *uri, grpc_resolved_address *resolved_addr);
 
+/** Parse bare IPv4 or IPv6 "IP:port" strings. */
+bool grpc_parse_ipv4_hostport(const char *hostport, grpc_resolved_address *addr,
+                              bool log_errors);
+bool grpc_parse_ipv6_hostport(const char *hostport, grpc_resolved_address *addr,
+                              bool log_errors);
+
 #endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_PARSE_ADDRESS_H */
diff --git a/src/core/ext/filters/client_channel/proxy_mapper.c b/src/core/ext/filters/client_channel/proxy_mapper.c
index 6dddd3c6da..c6ea5fc680 100644
--- a/src/core/ext/filters/client_channel/proxy_mapper.c
+++ b/src/core/ext/filters/client_channel/proxy_mapper.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2017, Google Inc.
- * All rights reserved.
+ * Copyright 2017 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/filters/client_channel/proxy_mapper.h b/src/core/ext/filters/client_channel/proxy_mapper.h
index d0c47d3090..a13861ccaf 100644
--- a/src/core/ext/filters/client_channel/proxy_mapper.h
+++ b/src/core/ext/filters/client_channel/proxy_mapper.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2017, Google Inc.
- * All rights reserved.
+ * Copyright 2017 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/filters/client_channel/proxy_mapper_registry.c b/src/core/ext/filters/client_channel/proxy_mapper_registry.c
index 7a39289a84..5f43a0596a 100644
--- a/src/core/ext/filters/client_channel/proxy_mapper_registry.c
+++ b/src/core/ext/filters/client_channel/proxy_mapper_registry.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2017, Google Inc.
- * All rights reserved.
+ * Copyright 2017 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/filters/client_channel/proxy_mapper_registry.h b/src/core/ext/filters/client_channel/proxy_mapper_registry.h
index 8b5686d664..99e54d1a78 100644
--- a/src/core/ext/filters/client_channel/proxy_mapper_registry.h
+++ b/src/core/ext/filters/client_channel/proxy_mapper_registry.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2017, Google Inc.
- * All rights reserved.
+ * Copyright 2017 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/filters/client_channel/resolver.c b/src/core/ext/filters/client_channel/resolver.c
index cafa2837f3..8401504fcf 100644
--- a/src/core/ext/filters/client_channel/resolver.c
+++ b/src/core/ext/filters/client_channel/resolver.c
@@ -1,39 +1,29 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
 #include "src/core/ext/filters/client_channel/resolver.h"
 #include "src/core/lib/iomgr/combiner.h"
 
+#ifndef NDEBUG
+grpc_tracer_flag grpc_trace_resolver_refcount =
+    GRPC_TRACER_INITIALIZER(false, "resolver_refcount");
+#endif
+
 void grpc_resolver_init(grpc_resolver *resolver,
                         const grpc_resolver_vtable *vtable,
                         grpc_combiner *combiner) {
@@ -42,25 +32,30 @@ void grpc_resolver_init(grpc_resolver *resolver,
   gpr_ref_init(&resolver->refs, 1);
 }
 
-#ifdef GRPC_RESOLVER_REFCOUNT_DEBUG
-void grpc_resolver_ref(grpc_resolver *resolver, grpc_closure_list *closure_list,
-                       const char *file, int line, const char *reason) {
-  gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG, "RESOLVER:%p   ref %d -> %d %s",
-          resolver, (int)resolver->refs.count, (int)resolver->refs.count + 1,
-          reason);
+#ifndef NDEBUG
+void grpc_resolver_ref(grpc_resolver *resolver, const char *file, int line,
+                       const char *reason) {
+  if (GRPC_TRACER_ON(grpc_trace_resolver_refcount)) {
+    gpr_atm old_refs = gpr_atm_no_barrier_load(&resolver->refs.count);
+    gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
+            "RESOLVER:%p   ref %" PRIdPTR " -> %" PRIdPTR " %s", resolver,
+            old_refs, old_refs + 1, reason);
+  }
 #else
 void grpc_resolver_ref(grpc_resolver *resolver) {
 #endif
   gpr_ref(&resolver->refs);
 }
 
-#ifdef GRPC_RESOLVER_REFCOUNT_DEBUG
-void grpc_resolver_unref(grpc_resolver *resolver,
-                         grpc_closure_list *closure_list, const char *file,
-                         int line, const char *reason) {
-  gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG, "RESOLVER:%p unref %d -> %d %s",
-          resolver, (int)resolver->refs.count, (int)resolver->refs.count - 1,
-          reason);
+#ifndef NDEBUG
+void grpc_resolver_unref(grpc_exec_ctx *exec_ctx, grpc_resolver *resolver,
+                         const char *file, int line, const char *reason) {
+  if (GRPC_TRACER_ON(grpc_trace_resolver_refcount)) {
+    gpr_atm old_refs = gpr_atm_no_barrier_load(&resolver->refs.count);
+    gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
+            "RESOLVER:%p unref %" PRIdPTR " -> %" PRIdPTR " %s", resolver,
+            old_refs, old_refs - 1, reason);
+  }
 #else
 void grpc_resolver_unref(grpc_exec_ctx *exec_ctx, grpc_resolver *resolver) {
 #endif
diff --git a/src/core/ext/filters/client_channel/resolver.h b/src/core/ext/filters/client_channel/resolver.h
index 55f9124b3a..ae9c8f66fe 100644
--- a/src/core/ext/filters/client_channel/resolver.h
+++ b/src/core/ext/filters/client_channel/resolver.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -40,6 +25,10 @@
 typedef struct grpc_resolver grpc_resolver;
 typedef struct grpc_resolver_vtable grpc_resolver_vtable;
 
+#ifndef NDEBUG
+extern grpc_tracer_flag grpc_trace_resolver_refcount;
+#endif
+
 /** \a grpc_resolver provides \a grpc_channel_args objects to its caller */
 struct grpc_resolver {
   const grpc_resolver_vtable *vtable;
@@ -56,17 +45,17 @@ struct grpc_resolver_vtable {
                       grpc_channel_args **result, grpc_closure *on_complete);
 };
 
-#ifdef GRPC_RESOLVER_REFCOUNT_DEBUG
+#ifndef NDEBUG
 #define GRPC_RESOLVER_REF(p, r) grpc_resolver_ref((p), __FILE__, __LINE__, (r))
-#define GRPC_RESOLVER_UNREF(cl, p, r) \
-  grpc_resolver_unref((cl), (p), __FILE__, __LINE__, (r))
+#define GRPC_RESOLVER_UNREF(e, p, r) \
+  grpc_resolver_unref((e), (p), __FILE__, __LINE__, (r))
 void grpc_resolver_ref(grpc_resolver *policy, const char *file, int line,
                        const char *reason);
-void grpc_resolver_unref(grpc_resolver *policy, grpc_closure_list *closure_list,
+void grpc_resolver_unref(grpc_exec_ctx *exec_ctx, grpc_resolver *policy,
                          const char *file, int line, const char *reason);
 #else
 #define GRPC_RESOLVER_REF(p, r) grpc_resolver_ref((p))
-#define GRPC_RESOLVER_UNREF(cl, p, r) grpc_resolver_unref((cl), (p))
+#define GRPC_RESOLVER_UNREF(e, p, r) grpc_resolver_unref((e), (p))
 void grpc_resolver_ref(grpc_resolver *policy);
 void grpc_resolver_unref(grpc_exec_ctx *exec_ctx, grpc_resolver *policy);
 #endif
diff --git a/src/core/ext/filters/client_channel/resolver/dns/c_ares/dns_resolver_ares.c b/src/core/ext/filters/client_channel/resolver/dns/c_ares/dns_resolver_ares.c
index ffaeeed324..04a7852323 100644
--- a/src/core/ext/filters/client_channel/resolver/dns/c_ares/dns_resolver_ares.c
+++ b/src/core/ext/filters/client_channel/resolver/dns/c_ares/dns_resolver_ares.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -61,6 +46,8 @@
 typedef struct {
   /** base class: must be first */
   grpc_resolver base;
+  /** DNS server to use (if not system default) */
+  char *dns_server;
   /** name to resolve (usually the same as target_name) */
   char *name_to_resolve;
   /** default port to use */
@@ -78,6 +65,8 @@ typedef struct {
   grpc_combiner *combiner;
   /** are we currently resolving? */
   bool resolving;
+  /** the pending resolving request */
+  grpc_ares_request *pending_request;
   /** which version of the result have we published? */
   int published_version;
   /** which version of the result is current? */
@@ -95,7 +84,7 @@ typedef struct {
   gpr_backoff backoff_state;
 
   /** currently resolving addresses */
-  grpc_resolved_addresses *addresses;
+  grpc_lb_addresses *lb_addresses;
 } ares_dns_resolver;
 
 static void dns_ares_destroy(grpc_exec_ctx *exec_ctx, grpc_resolver *r);
@@ -122,9 +111,12 @@ static void dns_ares_shutdown_locked(grpc_exec_ctx *exec_ctx,
   if (r->have_retry_timer) {
     grpc_timer_cancel(exec_ctx, &r->retry_timer);
   }
+  if (r->pending_request != NULL) {
+    grpc_cancel_ares_request(exec_ctx, r->pending_request);
+  }
   if (r->next_completion != NULL) {
     *r->target_result = NULL;
-    grpc_closure_sched(
+    GRPC_CLOSURE_SCHED(
         exec_ctx, r->next_completion,
         GRPC_ERROR_CREATE_FROM_STATIC_STRING("Resolver Shutdown"));
     r->next_completion = NULL;
@@ -158,20 +150,14 @@ static void dns_ares_on_resolved_locked(grpc_exec_ctx *exec_ctx, void *arg,
   grpc_channel_args *result = NULL;
   GPR_ASSERT(r->resolving);
   r->resolving = false;
-  if (r->addresses != NULL) {
-    grpc_lb_addresses *addresses = grpc_lb_addresses_create(
-        r->addresses->naddrs, NULL /* user_data_vtable */);
-    for (size_t i = 0; i < r->addresses->naddrs; ++i) {
-      grpc_lb_addresses_set_address(
-          addresses, i, &r->addresses->addrs[i].addr,
-          r->addresses->addrs[i].len, false /* is_balancer */,
-          NULL /* balancer_name */, NULL /* user_data */);
-    }
-    grpc_arg new_arg = grpc_lb_addresses_create_channel_arg(addresses);
+  r->pending_request = NULL;
+  if (r->lb_addresses != NULL) {
+    grpc_arg new_arg = grpc_lb_addresses_create_channel_arg(r->lb_addresses);
     result = grpc_channel_args_copy_and_add(r->channel_args, &new_arg, 1);
-    grpc_resolved_addresses_destroy(r->addresses);
-    grpc_lb_addresses_destroy(exec_ctx, addresses);
+    grpc_lb_addresses_destroy(exec_ctx, r->lb_addresses);
   } else {
+    const char *msg = grpc_error_string(error);
+    gpr_log(GPR_DEBUG, "dns resolution failed: %s", msg);
     gpr_timespec now = gpr_now(GPR_CLOCK_MONOTONIC);
     gpr_timespec next_try = gpr_backoff_step(&r->backoff_state, now);
     gpr_timespec timeout = gpr_time_sub(next_try, now);
@@ -220,10 +206,11 @@ static void dns_ares_start_resolving_locked(grpc_exec_ctx *exec_ctx,
   GRPC_RESOLVER_REF(&r->base, "dns-resolving");
   GPR_ASSERT(!r->resolving);
   r->resolving = true;
-  r->addresses = NULL;
-  grpc_resolve_address(exec_ctx, r->name_to_resolve, r->default_port,
-                       r->interested_parties, &r->dns_ares_on_resolved_locked,
-                       &r->addresses);
+  r->lb_addresses = NULL;
+  r->pending_request = grpc_dns_lookup_ares(
+      exec_ctx, r->dns_server, r->name_to_resolve, r->default_port,
+      r->interested_parties, &r->dns_ares_on_resolved_locked, &r->lb_addresses,
+      true /* check_grpclb */);
 }
 
 static void dns_ares_maybe_finish_next_locked(grpc_exec_ctx *exec_ctx,
@@ -233,7 +220,8 @@ static void dns_ares_maybe_finish_next_locked(grpc_exec_ctx *exec_ctx,
     *r->target_result = r->resolved_result == NULL
                             ? NULL
                             : grpc_channel_args_copy(r->resolved_result);
-    grpc_closure_sched(exec_ctx, r->next_completion, GRPC_ERROR_NONE);
+    gpr_log(GPR_DEBUG, "dns_ares_maybe_finish_next_locked");
+    GRPC_CLOSURE_SCHED(exec_ctx, r->next_completion, GRPC_ERROR_NONE);
     r->next_completion = NULL;
     r->published_version = r->resolved_version;
   }
@@ -246,6 +234,7 @@ static void dns_ares_destroy(grpc_exec_ctx *exec_ctx, grpc_resolver *gr) {
     grpc_channel_args_destroy(exec_ctx, r->resolved_result);
   }
   grpc_pollset_set_destroy(exec_ctx, r->interested_parties);
+  gpr_free(r->dns_server);
   gpr_free(r->name_to_resolve);
   gpr_free(r->default_port);
   grpc_channel_args_destroy(exec_ctx, r->channel_args);
@@ -255,16 +244,15 @@ static void dns_ares_destroy(grpc_exec_ctx *exec_ctx, grpc_resolver *gr) {
 static grpc_resolver *dns_ares_create(grpc_exec_ctx *exec_ctx,
                                       grpc_resolver_args *args,
                                       const char *default_port) {
-  // Get name from args.
+  /* Get name from args. */
   const char *path = args->uri->path;
-  if (0 != strcmp(args->uri->authority, "")) {
-    gpr_log(GPR_ERROR, "authority based dns uri's not supported");
-    return NULL;
-  }
   if (path[0] == '/') ++path;
-  // Create resolver.
+  /* Create resolver. */
   ares_dns_resolver *r = gpr_zalloc(sizeof(ares_dns_resolver));
   grpc_resolver_init(&r->base, &dns_ares_resolver_vtable, args->combiner);
+  if (0 != strcmp(args->uri->authority, "")) {
+    r->dns_server = gpr_strdup(args->uri->authority);
+  }
   r->name_to_resolve = gpr_strdup(path);
   r->default_port = gpr_strdup(default_port);
   r->channel_args = grpc_channel_args_copy(args->args);
@@ -278,12 +266,12 @@ static grpc_resolver *dns_ares_create(grpc_exec_ctx *exec_ctx,
                    GRPC_DNS_RECONNECT_JITTER,
                    GRPC_DNS_MIN_CONNECT_TIMEOUT_SECONDS * 1000,
                    GRPC_DNS_RECONNECT_MAX_BACKOFF_SECONDS * 1000);
-  grpc_closure_init(&r->dns_ares_on_retry_timer_locked,
+  GRPC_CLOSURE_INIT(&r->dns_ares_on_retry_timer_locked,
                     dns_ares_on_retry_timer_locked, r,
-                    grpc_combiner_scheduler(r->base.combiner, false));
-  grpc_closure_init(&r->dns_ares_on_resolved_locked,
+                    grpc_combiner_scheduler(r->base.combiner));
+  GRPC_CLOSURE_INIT(&r->dns_ares_on_resolved_locked,
                     dns_ares_on_resolved_locked, r,
-                    grpc_combiner_scheduler(r->base.combiner, false));
+                    grpc_combiner_scheduler(r->base.combiner));
   return &r->base;
 }
 
diff --git a/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver.h b/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver.h
index aa88940021..386012d2ed 100644
--- a/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver.h
+++ b/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver.h
@@ -1,41 +1,24 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
 #ifndef GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_RESOLVER_DNS_C_ARES_GRPC_ARES_EV_DRIVER_H
 #define GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_RESOLVER_DNS_C_ARES_GRPC_ARES_EV_DRIVER_H
 
-#include <ares.h>
-
 #include "src/core/lib/iomgr/exec_ctx.h"
 #include "src/core/lib/iomgr/pollset_set.h"
 
@@ -62,5 +45,9 @@ grpc_error *grpc_ares_ev_driver_create(grpc_ares_ev_driver **ev_driver,
    of ARES_ECANCELLED. */
 void grpc_ares_ev_driver_destroy(grpc_ares_ev_driver *ev_driver);
 
+/* Shutdown all the grpc_fds used by \a ev_driver */
+void grpc_ares_ev_driver_shutdown(grpc_exec_ctx *exec_ctx,
+                                  grpc_ares_ev_driver *ev_driver);
+
 #endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_RESOLVER_DNS_C_ARES_GRPC_ARES_EV_DRIVER_H \
           */
diff --git a/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver_posix.c b/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver_posix.c
index 1e4f3eb5ab..1ab8295e9e 100644
--- a/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver_posix.c
+++ b/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver_posix.c
@@ -1,39 +1,26 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 #include <grpc/support/port_platform.h>
 #include "src/core/lib/iomgr/port.h"
 #if GRPC_ARES == 1 && defined(GRPC_POSIX_SOCKET)
 
+#include <ares.h>
+
 #include "src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver.h"
 
 #include <grpc/support/alloc.h>
@@ -114,9 +101,12 @@ static void fd_node_destroy(grpc_exec_ctx *exec_ctx, fd_node *fdn) {
   GPR_ASSERT(!fdn->writable_registered);
   gpr_mu_destroy(&fdn->mu);
   grpc_pollset_set_del_fd(exec_ctx, fdn->ev_driver->pollset_set, fdn->grpc_fd);
-  grpc_fd_shutdown(exec_ctx, fdn->grpc_fd,
-                   GRPC_ERROR_CREATE_FROM_STATIC_STRING("fd node destroyed"));
-  grpc_fd_orphan(exec_ctx, fdn->grpc_fd, NULL, NULL, "c-ares query finished");
+  /* c-ares library has closed the fd inside grpc_fd. This fd may be picked up
+     immediately by another thread, and should not be closed by the following
+     grpc_fd_orphan. To prevent this fd from being closed by grpc_fd_orphan,
+     a fd pointer is provided. */
+  int fd;
+  grpc_fd_orphan(exec_ctx, fdn->grpc_fd, NULL, &fd, "c-ares query finished");
   gpr_free(fdn);
 }
 
@@ -155,6 +145,20 @@ void grpc_ares_ev_driver_destroy(grpc_ares_ev_driver *ev_driver) {
   grpc_ares_ev_driver_unref(ev_driver);
 }
 
+void grpc_ares_ev_driver_shutdown(grpc_exec_ctx *exec_ctx,
+                                  grpc_ares_ev_driver *ev_driver) {
+  gpr_mu_lock(&ev_driver->mu);
+  ev_driver->shutting_down = true;
+  fd_node *fn = ev_driver->fds;
+  while (fn != NULL) {
+    grpc_fd_shutdown(
+        exec_ctx, fn->grpc_fd,
+        GRPC_ERROR_CREATE_FROM_STATIC_STRING("grpc_ares_ev_driver_shutdown"));
+    fn = fn->next;
+  }
+  gpr_mu_unlock(&ev_driver->mu);
+}
+
 // Search fd in the fd_node list head. This is an O(n) search, the max possible
 // value of n is ARES_GETSOCK_MAXNUM (16). n is typically 1 - 2 in our tests.
 static fd_node *pop_fd_node(fd_node **head, int fd) {
@@ -255,9 +259,9 @@ static void grpc_ares_notify_on_event_locked(grpc_exec_ctx *exec_ctx,
           fdn->readable_registered = false;
           fdn->writable_registered = false;
           gpr_mu_init(&fdn->mu);
-          grpc_closure_init(&fdn->read_closure, on_readable_cb, fdn,
+          GRPC_CLOSURE_INIT(&fdn->read_closure, on_readable_cb, fdn,
                             grpc_schedule_on_exec_ctx);
-          grpc_closure_init(&fdn->write_closure, on_writable_cb, fdn,
+          GRPC_CLOSURE_INIT(&fdn->write_closure, on_writable_cb, fdn,
                             grpc_schedule_on_exec_ctx);
           grpc_pollset_set_add_fd(exec_ctx, ev_driver->pollset_set,
                                   fdn->grpc_fd);
diff --git a/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.c b/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.c
index 09c46a66e0..9065e33613 100644
--- a/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.c
+++ b/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -48,7 +33,11 @@
 #include <grpc/support/string_util.h>
 #include <grpc/support/time.h>
 #include <grpc/support/useful.h>
+#include <nameser.h>
+
+#include "src/core/ext/filters/client_channel/parse_address.h"
 #include "src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver.h"
+#include "src/core/lib/iomgr/error.h"
 #include "src/core/lib/iomgr/executor.h"
 #include "src/core/lib/iomgr/iomgr_internal.h"
 #include "src/core/lib/iomgr/sockaddr_utils.h"
@@ -57,18 +46,14 @@
 static gpr_once g_basic_init = GPR_ONCE_INIT;
 static gpr_mu g_init_mu;
 
-typedef struct grpc_ares_request {
+struct grpc_ares_request {
+  /** indicates the DNS server to use, if specified */
+  struct ares_addr_port_node dns_server_addr;
   /** following members are set in grpc_resolve_address_ares_impl */
-  /** host to resolve, parsed from the name to resolve */
-  char *host;
-  /** port to fill in sockaddr_in, parsed from the name to resolve */
-  char *port;
-  /** default port to use */
-  char *default_port;
   /** closure to call when the request completes */
   grpc_closure *on_done;
   /** the pointer to receive the resolved addresses */
-  grpc_resolved_addresses **addrs_out;
+  grpc_lb_addresses **lb_addrs_out;
   /** the evernt driver used by this request */
   grpc_ares_ev_driver *ev_driver;
   /** number of ongoing queries */
@@ -80,7 +65,19 @@ typedef struct grpc_ares_request {
   bool success;
   /** the errors explaining the request failure, set in on_done_cb */
   grpc_error *error;
-} grpc_ares_request;
+};
+
+typedef struct grpc_ares_hostbyname_request {
+  /** following members are set in create_hostbyname_request */
+  /** the top-level request instance */
+  grpc_ares_request *parent_request;
+  /** host to resolve, parsed from the name to resolve */
+  char *host;
+  /** port to fill in sockaddr_in, parsed from the name to resolve */
+  uint16_t port;
+  /** is it a grpclb address */
+  bool is_balancer;
+} grpc_ares_hostbyname_request;
 
 static void do_basic_init(void) { gpr_mu_init(&g_init_mu); }
 
@@ -93,6 +90,10 @@ static uint16_t strhtons(const char *port) {
   return htons((unsigned short)atoi(port));
 }
 
+static void grpc_ares_request_ref(grpc_ares_request *r) {
+  gpr_ref(&r->pending_queries);
+}
+
 static void grpc_ares_request_unref(grpc_exec_ctx *exec_ctx,
                                     grpc_ares_request *r) {
   /* If there are no pending queries, invoke on_done callback and destroy the
@@ -106,74 +107,102 @@ static void grpc_ares_request_unref(grpc_exec_ctx *exec_ctx,
          acquire locks in on_done. ares_dns_resolver is using combiner to
          protect resources needed by on_done. */
       grpc_exec_ctx new_exec_ctx = GRPC_EXEC_CTX_INIT;
-      grpc_closure_sched(&new_exec_ctx, r->on_done, r->error);
+      GRPC_CLOSURE_SCHED(&new_exec_ctx, r->on_done, r->error);
       grpc_exec_ctx_finish(&new_exec_ctx);
     } else {
-      grpc_closure_sched(exec_ctx, r->on_done, r->error);
+      GRPC_CLOSURE_SCHED(exec_ctx, r->on_done, r->error);
     }
     gpr_mu_destroy(&r->mu);
     grpc_ares_ev_driver_destroy(r->ev_driver);
-    gpr_free(r->host);
-    gpr_free(r->port);
-    gpr_free(r->default_port);
     gpr_free(r);
   }
 }
 
-static void on_done_cb(void *arg, int status, int timeouts,
-                       struct hostent *hostent) {
-  grpc_ares_request *r = (grpc_ares_request *)arg;
+static grpc_ares_hostbyname_request *create_hostbyname_request(
+    grpc_ares_request *parent_request, char *host, uint16_t port,
+    bool is_balancer) {
+  grpc_ares_hostbyname_request *hr =
+      gpr_zalloc(sizeof(grpc_ares_hostbyname_request));
+  hr->parent_request = parent_request;
+  hr->host = gpr_strdup(host);
+  hr->port = port;
+  hr->is_balancer = is_balancer;
+  grpc_ares_request_ref(parent_request);
+  return hr;
+}
+
+static void destroy_hostbyname_request(grpc_exec_ctx *exec_ctx,
+                                       grpc_ares_hostbyname_request *hr) {
+  grpc_ares_request_unref(exec_ctx, hr->parent_request);
+  gpr_free(hr->host);
+  gpr_free(hr);
+}
+
+static void on_hostbyname_done_cb(void *arg, int status, int timeouts,
+                                  struct hostent *hostent) {
+  grpc_ares_hostbyname_request *hr = (grpc_ares_hostbyname_request *)arg;
+  grpc_ares_request *r = hr->parent_request;
   gpr_mu_lock(&r->mu);
   if (status == ARES_SUCCESS) {
     GRPC_ERROR_UNREF(r->error);
     r->error = GRPC_ERROR_NONE;
     r->success = true;
-    grpc_resolved_addresses **addresses = r->addrs_out;
-    if (*addresses == NULL) {
-      *addresses = gpr_malloc(sizeof(grpc_resolved_addresses));
-      (*addresses)->naddrs = 0;
-      (*addresses)->addrs = NULL;
+    grpc_lb_addresses **lb_addresses = r->lb_addrs_out;
+    if (*lb_addresses == NULL) {
+      *lb_addresses = grpc_lb_addresses_create(0, NULL);
     }
-    size_t prev_naddr = (*addresses)->naddrs;
+    size_t prev_naddr = (*lb_addresses)->num_addresses;
     size_t i;
     for (i = 0; hostent->h_addr_list[i] != NULL; i++) {
     }
-    (*addresses)->naddrs += i;
-    (*addresses)->addrs =
-        gpr_realloc((*addresses)->addrs,
-                    sizeof(grpc_resolved_address) * (*addresses)->naddrs);
-    for (i = prev_naddr; i < (*addresses)->naddrs; i++) {
-      memset(&(*addresses)->addrs[i], 0, sizeof(grpc_resolved_address));
-      if (hostent->h_addrtype == AF_INET6) {
-        (*addresses)->addrs[i].len = sizeof(struct sockaddr_in6);
-        struct sockaddr_in6 *addr =
-            (struct sockaddr_in6 *)&(*addresses)->addrs[i].addr;
-        addr->sin6_family = (sa_family_t)hostent->h_addrtype;
-        addr->sin6_port = strhtons(r->port);
-
-        char output[INET6_ADDRSTRLEN];
-        memcpy(&addr->sin6_addr, hostent->h_addr_list[i - prev_naddr],
-               sizeof(struct in6_addr));
-        ares_inet_ntop(AF_INET6, &addr->sin6_addr, output, INET6_ADDRSTRLEN);
-        gpr_log(GPR_DEBUG,
-                "c-ares resolver gets a AF_INET6 result: \n"
-                "  addr: %s\n  port: %s\n  sin6_scope_id: %d\n",
-                output, r->port, addr->sin6_scope_id);
-      } else {
-        (*addresses)->addrs[i].len = sizeof(struct sockaddr_in);
-        struct sockaddr_in *addr =
-            (struct sockaddr_in *)&(*addresses)->addrs[i].addr;
-        memcpy(&addr->sin_addr, hostent->h_addr_list[i - prev_naddr],
-               sizeof(struct in_addr));
-        addr->sin_family = (sa_family_t)hostent->h_addrtype;
-        addr->sin_port = strhtons(r->port);
-
-        char output[INET_ADDRSTRLEN];
-        ares_inet_ntop(AF_INET, &addr->sin_addr, output, INET_ADDRSTRLEN);
-        gpr_log(GPR_DEBUG,
-                "c-ares resolver gets a AF_INET result: \n"
-                "  addr: %s\n  port: %s\n",
-                output, r->port);
+    (*lb_addresses)->num_addresses += i;
+    (*lb_addresses)->addresses =
+        gpr_realloc((*lb_addresses)->addresses,
+                    sizeof(grpc_lb_address) * (*lb_addresses)->num_addresses);
+    for (i = prev_naddr; i < (*lb_addresses)->num_addresses; i++) {
+      switch (hostent->h_addrtype) {
+        case AF_INET6: {
+          size_t addr_len = sizeof(struct sockaddr_in6);
+          struct sockaddr_in6 addr;
+          memset(&addr, 0, addr_len);
+          memcpy(&addr.sin6_addr, hostent->h_addr_list[i - prev_naddr],
+                 sizeof(struct in6_addr));
+          addr.sin6_family = (sa_family_t)hostent->h_addrtype;
+          addr.sin6_port = hr->port;
+          grpc_lb_addresses_set_address(
+              *lb_addresses, i, &addr, addr_len,
+              hr->is_balancer /* is_balancer */,
+              hr->is_balancer ? strdup(hr->host) : NULL /* balancer_name */,
+              NULL /* user_data */);
+          char output[INET6_ADDRSTRLEN];
+          ares_inet_ntop(AF_INET6, &addr.sin6_addr, output, INET6_ADDRSTRLEN);
+          gpr_log(GPR_DEBUG,
+                  "c-ares resolver gets a AF_INET6 result: \n"
+                  "  addr: %s\n  port: %d\n  sin6_scope_id: %d\n",
+                  output, ntohs(hr->port), addr.sin6_scope_id);
+          break;
+        }
+        case AF_INET: {
+          size_t addr_len = sizeof(struct sockaddr_in);
+          struct sockaddr_in addr;
+          memset(&addr, 0, addr_len);
+          memcpy(&addr.sin_addr, hostent->h_addr_list[i - prev_naddr],
+                 sizeof(struct in_addr));
+          addr.sin_family = (sa_family_t)hostent->h_addrtype;
+          addr.sin_port = hr->port;
+          grpc_lb_addresses_set_address(
+              *lb_addresses, i, &addr, addr_len,
+              hr->is_balancer /* is_balancer */,
+              hr->is_balancer ? strdup(hr->host) : NULL /* balancer_name */,
+              NULL /* user_data */);
+          char output[INET_ADDRSTRLEN];
+          ares_inet_ntop(AF_INET, &addr.sin_addr, output, INET_ADDRSTRLEN);
+          gpr_log(GPR_DEBUG,
+                  "c-ares resolver gets a AF_INET result: \n"
+                  "  addr: %s\n  port: %d\n",
+                  output, ntohs(hr->port));
+          break;
+        }
       }
     }
   } else if (!r->success) {
@@ -189,14 +218,59 @@ static void on_done_cb(void *arg, int status, int timeouts,
     }
   }
   gpr_mu_unlock(&r->mu);
-  grpc_ares_request_unref(NULL, r);
+  destroy_hostbyname_request(NULL, hr);
+}
+
+static void on_srv_query_done_cb(void *arg, int status, int timeouts,
+                                 unsigned char *abuf, int alen) {
+  grpc_ares_request *r = (grpc_ares_request *)arg;
+  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
+  gpr_log(GPR_DEBUG, "on_query_srv_done_cb");
+  if (status == ARES_SUCCESS) {
+    gpr_log(GPR_DEBUG, "on_query_srv_done_cb ARES_SUCCESS");
+    struct ares_srv_reply *reply;
+    const int parse_status = ares_parse_srv_reply(abuf, alen, &reply);
+    if (parse_status == ARES_SUCCESS) {
+      ares_channel *channel = grpc_ares_ev_driver_get_channel(r->ev_driver);
+      for (struct ares_srv_reply *srv_it = reply; srv_it != NULL;
+           srv_it = srv_it->next) {
+        if (grpc_ipv6_loopback_available()) {
+          grpc_ares_hostbyname_request *hr = create_hostbyname_request(
+              r, srv_it->host, htons(srv_it->port), true /* is_balancer */);
+          ares_gethostbyname(*channel, hr->host, AF_INET6,
+                             on_hostbyname_done_cb, hr);
+        }
+        grpc_ares_hostbyname_request *hr = create_hostbyname_request(
+            r, srv_it->host, htons(srv_it->port), true /* is_balancer */);
+        ares_gethostbyname(*channel, hr->host, AF_INET, on_hostbyname_done_cb,
+                           hr);
+        grpc_ares_ev_driver_start(&exec_ctx, r->ev_driver);
+      }
+    }
+    if (reply != NULL) {
+      ares_free_data(reply);
+    }
+  } else if (!r->success) {
+    char *error_msg;
+    gpr_asprintf(&error_msg, "C-ares status is not ARES_SUCCESS: %s",
+                 ares_strerror(status));
+    grpc_error *error = GRPC_ERROR_CREATE_FROM_COPIED_STRING(error_msg);
+    gpr_free(error_msg);
+    if (r->error == GRPC_ERROR_NONE) {
+      r->error = error;
+    } else {
+      r->error = grpc_error_add_child(error, r->error);
+    }
+  }
+  grpc_ares_request_unref(&exec_ctx, r);
+  grpc_exec_ctx_finish(&exec_ctx);
 }
 
-void grpc_resolve_address_ares_impl(grpc_exec_ctx *exec_ctx, const char *name,
-                                    const char *default_port,
-                                    grpc_pollset_set *interested_parties,
-                                    grpc_closure *on_done,
-                                    grpc_resolved_addresses **addrs) {
+static grpc_ares_request *grpc_dns_lookup_ares_impl(
+    grpc_exec_ctx *exec_ctx, const char *dns_server, const char *name,
+    const char *default_port, grpc_pollset_set *interested_parties,
+    grpc_closure *on_done, grpc_lb_addresses **addrs, bool check_grpclb) {
+  grpc_error *error = GRPC_ERROR_NONE;
   /* TODO(zyc): Enable tracing after #9603 is checked in */
   /* if (grpc_dns_trace) {
       gpr_log(GPR_DEBUG, "resolve_address (blocking): name=%s, default_port=%s",
@@ -208,60 +282,111 @@ void grpc_resolve_address_ares_impl(grpc_exec_ctx *exec_ctx, const char *name,
   char *port;
   gpr_split_host_port(name, &host, &port);
   if (host == NULL) {
-    grpc_error *err = grpc_error_set_str(
+    error = grpc_error_set_str(
         GRPC_ERROR_CREATE_FROM_STATIC_STRING("unparseable host:port"),
         GRPC_ERROR_STR_TARGET_ADDRESS, grpc_slice_from_copied_string(name));
-    grpc_closure_sched(exec_ctx, on_done, err);
     goto error_cleanup;
   } else if (port == NULL) {
     if (default_port == NULL) {
-      grpc_error *err = grpc_error_set_str(
+      error = grpc_error_set_str(
           GRPC_ERROR_CREATE_FROM_STATIC_STRING("no port in name"),
           GRPC_ERROR_STR_TARGET_ADDRESS, grpc_slice_from_copied_string(name));
-      grpc_closure_sched(exec_ctx, on_done, err);
       goto error_cleanup;
     }
     port = gpr_strdup(default_port);
   }
 
   grpc_ares_ev_driver *ev_driver;
-  grpc_error *err = grpc_ares_ev_driver_create(&ev_driver, interested_parties);
-  if (err != GRPC_ERROR_NONE) {
-    GRPC_LOG_IF_ERROR("grpc_ares_ev_driver_create() failed", err);
-    goto error_cleanup;
-  }
+  error = grpc_ares_ev_driver_create(&ev_driver, interested_parties);
+  if (error != GRPC_ERROR_NONE) goto error_cleanup;
 
   grpc_ares_request *r = gpr_malloc(sizeof(grpc_ares_request));
   gpr_mu_init(&r->mu);
   r->ev_driver = ev_driver;
   r->on_done = on_done;
-  r->addrs_out = addrs;
-  r->default_port = gpr_strdup(default_port);
-  r->port = port;
-  r->host = host;
+  r->lb_addrs_out = addrs;
   r->success = false;
   r->error = GRPC_ERROR_NONE;
   ares_channel *channel = grpc_ares_ev_driver_get_channel(r->ev_driver);
-  gpr_ref_init(&r->pending_queries, 2);
+
+  // If dns_server is specified, use it.
+  if (dns_server != NULL) {
+    gpr_log(GPR_INFO, "Using DNS server %s", dns_server);
+    grpc_resolved_address addr;
+    if (grpc_parse_ipv4_hostport(dns_server, &addr, false /* log_errors */)) {
+      r->dns_server_addr.family = AF_INET;
+      memcpy(&r->dns_server_addr.addr.addr4, addr.addr, addr.len);
+      r->dns_server_addr.tcp_port = grpc_sockaddr_get_port(&addr);
+      r->dns_server_addr.udp_port = grpc_sockaddr_get_port(&addr);
+    } else if (grpc_parse_ipv6_hostport(dns_server, &addr,
+                                        false /* log_errors */)) {
+      r->dns_server_addr.family = AF_INET6;
+      memcpy(&r->dns_server_addr.addr.addr6, addr.addr, addr.len);
+      r->dns_server_addr.tcp_port = grpc_sockaddr_get_port(&addr);
+      r->dns_server_addr.udp_port = grpc_sockaddr_get_port(&addr);
+    } else {
+      error = grpc_error_set_str(
+          GRPC_ERROR_CREATE_FROM_STATIC_STRING("cannot parse authority"),
+          GRPC_ERROR_STR_TARGET_ADDRESS, grpc_slice_from_copied_string(name));
+      gpr_free(r);
+      goto error_cleanup;
+    }
+    int status = ares_set_servers_ports(*channel, &r->dns_server_addr);
+    if (status != ARES_SUCCESS) {
+      char *error_msg;
+      gpr_asprintf(&error_msg, "C-ares status is not ARES_SUCCESS: %s",
+                   ares_strerror(status));
+      error = GRPC_ERROR_CREATE_FROM_COPIED_STRING(error_msg);
+      gpr_free(error_msg);
+      gpr_free(r);
+      goto error_cleanup;
+    }
+  }
+  // An extra reference is put here to avoid destroying the request in
+  // on_done_cb before calling grpc_ares_ev_driver_start.
+  gpr_ref_init(&r->pending_queries, 1);
   if (grpc_ipv6_loopback_available()) {
-    gpr_ref(&r->pending_queries);
-    ares_gethostbyname(*channel, r->host, AF_INET6, on_done_cb, r);
+    grpc_ares_hostbyname_request *hr = create_hostbyname_request(
+        r, host, strhtons(port), false /* is_balancer */);
+    ares_gethostbyname(*channel, hr->host, AF_INET6, on_hostbyname_done_cb, hr);
+  }
+  grpc_ares_hostbyname_request *hr = create_hostbyname_request(
+      r, host, strhtons(port), false /* is_balancer */);
+  ares_gethostbyname(*channel, hr->host, AF_INET, on_hostbyname_done_cb, hr);
+  if (check_grpclb) {
+    /* Query the SRV record */
+    grpc_ares_request_ref(r);
+    char *service_name;
+    gpr_asprintf(&service_name, "_grpclb._tcp.%s", host);
+    ares_query(*channel, service_name, ns_c_in, ns_t_srv, on_srv_query_done_cb,
+               r);
+    gpr_free(service_name);
   }
-  ares_gethostbyname(*channel, r->host, AF_INET, on_done_cb, r);
   /* TODO(zyc): Handle CNAME records here. */
   grpc_ares_ev_driver_start(exec_ctx, r->ev_driver);
   grpc_ares_request_unref(exec_ctx, r);
-  return;
+  gpr_free(host);
+  gpr_free(port);
+  return r;
 
 error_cleanup:
+  GRPC_CLOSURE_SCHED(exec_ctx, on_done, error);
   gpr_free(host);
   gpr_free(port);
+  return NULL;
 }
 
-void (*grpc_resolve_address_ares)(
-    grpc_exec_ctx *exec_ctx, const char *name, const char *default_port,
-    grpc_pollset_set *interested_parties, grpc_closure *on_done,
-    grpc_resolved_addresses **addrs) = grpc_resolve_address_ares_impl;
+grpc_ares_request *(*grpc_dns_lookup_ares)(
+    grpc_exec_ctx *exec_ctx, const char *dns_server, const char *name,
+    const char *default_port, grpc_pollset_set *interested_parties,
+    grpc_closure *on_done, grpc_lb_addresses **addrs,
+    bool check_grpclb) = grpc_dns_lookup_ares_impl;
+
+void grpc_cancel_ares_request(grpc_exec_ctx *exec_ctx, grpc_ares_request *r) {
+  if (grpc_dns_lookup_ares == grpc_dns_lookup_ares_impl) {
+    grpc_ares_ev_driver_shutdown(exec_ctx, r->ev_driver);
+  }
+}
 
 grpc_error *grpc_ares_init(void) {
   gpr_once_init(&g_basic_init, do_basic_init);
@@ -286,4 +411,66 @@ void grpc_ares_cleanup(void) {
   gpr_mu_unlock(&g_init_mu);
 }
 
+/*
+ * grpc_resolve_address_ares related structs and functions
+ */
+
+typedef struct grpc_resolve_address_ares_request {
+  /** the pointer to receive the resolved addresses */
+  grpc_resolved_addresses **addrs_out;
+  /** currently resolving lb addresses */
+  grpc_lb_addresses *lb_addrs;
+  /** closure to call when the resolve_address_ares request completes */
+  grpc_closure *on_resolve_address_done;
+  /** a closure wrapping on_dns_lookup_done_cb, which should be invoked when the
+      grpc_dns_lookup_ares operation is done. */
+  grpc_closure on_dns_lookup_done;
+} grpc_resolve_address_ares_request;
+
+static void on_dns_lookup_done_cb(grpc_exec_ctx *exec_ctx, void *arg,
+                                  grpc_error *error) {
+  grpc_resolve_address_ares_request *r =
+      (grpc_resolve_address_ares_request *)arg;
+  grpc_resolved_addresses **resolved_addresses = r->addrs_out;
+  if (r->lb_addrs == NULL || r->lb_addrs->num_addresses == 0) {
+    *resolved_addresses = NULL;
+  } else {
+    *resolved_addresses = gpr_zalloc(sizeof(grpc_resolved_addresses));
+    (*resolved_addresses)->naddrs = r->lb_addrs->num_addresses;
+    (*resolved_addresses)->addrs = gpr_zalloc(sizeof(grpc_resolved_address) *
+                                              (*resolved_addresses)->naddrs);
+    for (size_t i = 0; i < (*resolved_addresses)->naddrs; i++) {
+      GPR_ASSERT(!r->lb_addrs->addresses[i].is_balancer);
+      memcpy(&(*resolved_addresses)->addrs[i],
+             &r->lb_addrs->addresses[i].address, sizeof(grpc_resolved_address));
+    }
+  }
+  GRPC_CLOSURE_SCHED(exec_ctx, r->on_resolve_address_done,
+                     GRPC_ERROR_REF(error));
+  grpc_lb_addresses_destroy(exec_ctx, r->lb_addrs);
+  gpr_free(r);
+}
+
+static void grpc_resolve_address_ares_impl(grpc_exec_ctx *exec_ctx,
+                                           const char *name,
+                                           const char *default_port,
+                                           grpc_pollset_set *interested_parties,
+                                           grpc_closure *on_done,
+                                           grpc_resolved_addresses **addrs) {
+  grpc_resolve_address_ares_request *r =
+      gpr_zalloc(sizeof(grpc_resolve_address_ares_request));
+  r->addrs_out = addrs;
+  r->on_resolve_address_done = on_done;
+  GRPC_CLOSURE_INIT(&r->on_dns_lookup_done, on_dns_lookup_done_cb, r,
+                    grpc_schedule_on_exec_ctx);
+  grpc_dns_lookup_ares(exec_ctx, NULL /* dns_server */, name, default_port,
+                       interested_parties, &r->on_dns_lookup_done, &r->lb_addrs,
+                       false /* check_grpclb */);
+}
+
+void (*grpc_resolve_address_ares)(
+    grpc_exec_ctx *exec_ctx, const char *name, const char *default_port,
+    grpc_pollset_set *interested_parties, grpc_closure *on_done,
+    grpc_resolved_addresses **addrs) = grpc_resolve_address_ares_impl;
+
 #endif /* GRPC_ARES == 1 && !defined(GRPC_UV) */
diff --git a/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.h b/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.h
index 3dd40ea268..5d2d6c993b 100644
--- a/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.h
+++ b/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.h
@@ -1,44 +1,32 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
 #ifndef GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_RESOLVER_DNS_C_ARES_GRPC_ARES_WRAPPER_H
 #define GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_RESOLVER_DNS_C_ARES_GRPC_ARES_WRAPPER_H
 
+#include "src/core/ext/filters/client_channel/lb_policy_factory.h"
 #include "src/core/lib/iomgr/exec_ctx.h"
 #include "src/core/lib/iomgr/iomgr.h"
 #include "src/core/lib/iomgr/polling_entity.h"
 #include "src/core/lib/iomgr/resolve_address.h"
 
+typedef struct grpc_ares_request grpc_ares_request;
+
 /* Asynchronously resolve addr. Use \a default_port if a port isn't designated
    in addr, otherwise use the port in addr. grpc_ares_init() must be called at
    least once before this function. \a on_done may be called directly in this
@@ -51,6 +39,22 @@ extern void (*grpc_resolve_address_ares)(grpc_exec_ctx *exec_ctx,
                                          grpc_closure *on_done,
                                          grpc_resolved_addresses **addresses);
 
+/* Asynchronously resolve addr. It will try to resolve grpclb SRV records in
+  addition to the normal address records. For normal address records, it uses
+  \a default_port if a port isn't designated in \a addr, otherwise it uses the
+  port in \a addr. grpc_ares_init() must be called at least once before this
+  function. \a on_done may be called directly in this function without being
+  scheduled with \a exec_ctx, it must not try to acquire locks that are being
+  held by the caller. */
+extern grpc_ares_request *(*grpc_dns_lookup_ares)(
+    grpc_exec_ctx *exec_ctx, const char *dns_server, const char *addr,
+    const char *default_port, grpc_pollset_set *interested_parties,
+    grpc_closure *on_done, grpc_lb_addresses **addresses, bool check_grpclb);
+
+/* Cancel the pending grpc_ares_request \a request */
+void grpc_cancel_ares_request(grpc_exec_ctx *exec_ctx,
+                              grpc_ares_request *request);
+
 /* Initialize gRPC ares wrapper. Must be called at least once before
    grpc_resolve_address_ares(). */
 grpc_error *grpc_ares_init(void);
diff --git a/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper_fallback.c b/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper_fallback.c
new file mode 100644
index 0000000000..b67636a3e4
--- /dev/null
+++ b/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper_fallback.c
@@ -0,0 +1,59 @@
+/*
+ *
+ * Copyright 2016-2017 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+#include <grpc/support/port_platform.h>
+#if GRPC_ARES != 1 || defined(GRPC_UV)
+
+#include "src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.h"
+
+struct grpc_ares_request {
+  char val;
+};
+
+static grpc_ares_request *grpc_dns_lookup_ares_impl(
+    grpc_exec_ctx *exec_ctx, const char *dns_server, const char *name,
+    const char *default_port, grpc_pollset_set *interested_parties,
+    grpc_closure *on_done, grpc_lb_addresses **addrs, bool check_grpclb) {
+  return NULL;
+}
+
+grpc_ares_request *(*grpc_dns_lookup_ares)(
+    grpc_exec_ctx *exec_ctx, const char *dns_server, const char *name,
+    const char *default_port, grpc_pollset_set *interested_parties,
+    grpc_closure *on_done, grpc_lb_addresses **addrs,
+    bool check_grpclb) = grpc_dns_lookup_ares_impl;
+
+void grpc_cancel_ares_request(grpc_exec_ctx *exec_ctx, grpc_ares_request *r) {}
+
+grpc_error *grpc_ares_init(void) { return GRPC_ERROR_NONE; }
+
+void grpc_ares_cleanup(void) {}
+
+static void grpc_resolve_address_ares_impl(grpc_exec_ctx *exec_ctx,
+                                           const char *name,
+                                           const char *default_port,
+                                           grpc_pollset_set *interested_parties,
+                                           grpc_closure *on_done,
+                                           grpc_resolved_addresses **addrs) {}
+
+void (*grpc_resolve_address_ares)(
+    grpc_exec_ctx *exec_ctx, const char *name, const char *default_port,
+    grpc_pollset_set *interested_parties, grpc_closure *on_done,
+    grpc_resolved_addresses **addrs) = grpc_resolve_address_ares_impl;
+
+#endif /* GRPC_ARES != 1 || defined(GRPC_UV) */
diff --git a/src/core/ext/filters/client_channel/resolver/dns/native/dns_resolver.c b/src/core/ext/filters/client_channel/resolver/dns/native/dns_resolver.c
index ebe6a07215..5ea75f0554 100644
--- a/src/core/ext/filters/client_channel/resolver/dns/native/dns_resolver.c
+++ b/src/core/ext/filters/client_channel/resolver/dns/native/dns_resolver.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -114,7 +99,7 @@ static void dns_shutdown_locked(grpc_exec_ctx *exec_ctx,
   }
   if (r->next_completion != NULL) {
     *r->target_result = NULL;
-    grpc_closure_sched(
+    GRPC_CLOSURE_SCHED(
         exec_ctx, r->next_completion,
         GRPC_ERROR_CREATE_FROM_STATIC_STRING("Resolver Shutdown"));
     r->next_completion = NULL;
@@ -147,7 +132,7 @@ static void dns_next_locked(grpc_exec_ctx *exec_ctx, grpc_resolver *resolver,
 
 static void dns_on_retry_timer_locked(grpc_exec_ctx *exec_ctx, void *arg,
                                       grpc_error *error) {
-  dns_resolver *r = arg;
+  dns_resolver *r = (dns_resolver *)arg;
 
   r->have_retry_timer = false;
   if (error == GRPC_ERROR_NONE) {
@@ -161,7 +146,7 @@ static void dns_on_retry_timer_locked(grpc_exec_ctx *exec_ctx, void *arg,
 
 static void dns_on_resolved_locked(grpc_exec_ctx *exec_ctx, void *arg,
                                    grpc_error *error) {
-  dns_resolver *r = arg;
+  dns_resolver *r = (dns_resolver *)arg;
   grpc_channel_args *result = NULL;
   GPR_ASSERT(r->resolving);
   r->resolving = false;
@@ -193,8 +178,8 @@ static void dns_on_resolved_locked(grpc_exec_ctx *exec_ctx, void *arg,
     } else {
       gpr_log(GPR_DEBUG, "retrying immediately");
     }
-    grpc_closure_init(&r->on_retry, dns_on_retry_timer_locked, r,
-                      grpc_combiner_scheduler(r->base.combiner, false));
+    GRPC_CLOSURE_INIT(&r->on_retry, dns_on_retry_timer_locked, r,
+                      grpc_combiner_scheduler(r->base.combiner));
     grpc_timer_init(exec_ctx, &r->retry_timer, next_try, &r->on_retry, now);
   }
   if (r->resolved_result != NULL) {
@@ -215,8 +200,8 @@ static void dns_start_resolving_locked(grpc_exec_ctx *exec_ctx,
   r->addresses = NULL;
   grpc_resolve_address(
       exec_ctx, r->name_to_resolve, r->default_port, r->interested_parties,
-      grpc_closure_create(dns_on_resolved_locked, r,
-                          grpc_combiner_scheduler(r->base.combiner, false)),
+      GRPC_CLOSURE_CREATE(dns_on_resolved_locked, r,
+                          grpc_combiner_scheduler(r->base.combiner)),
       &r->addresses);
 }
 
@@ -227,7 +212,7 @@ static void dns_maybe_finish_next_locked(grpc_exec_ctx *exec_ctx,
     *r->target_result = r->resolved_result == NULL
                             ? NULL
                             : grpc_channel_args_copy(r->resolved_result);
-    grpc_closure_sched(exec_ctx, r->next_completion, GRPC_ERROR_NONE);
+    GRPC_CLOSURE_SCHED(exec_ctx, r->next_completion, GRPC_ERROR_NONE);
     r->next_completion = NULL;
     r->published_version = r->resolved_version;
   }
@@ -256,7 +241,7 @@ static grpc_resolver *dns_create(grpc_exec_ctx *exec_ctx,
   char *path = args->uri->path;
   if (path[0] == '/') ++path;
   // Create resolver.
-  dns_resolver *r = gpr_zalloc(sizeof(dns_resolver));
+  dns_resolver *r = (dns_resolver *)gpr_zalloc(sizeof(dns_resolver));
   grpc_resolver_init(&r->base, &dns_resolver_vtable, args->combiner);
   r->name_to_resolve = gpr_strdup(path);
   r->default_port = gpr_strdup(default_port);
diff --git a/src/core/ext/filters/client_channel/resolver/fake/fake_resolver.c b/src/core/ext/filters/client_channel/resolver/fake/fake_resolver.c
new file mode 100644
index 0000000000..56ed4371a9
--- /dev/null
+++ b/src/core/ext/filters/client_channel/resolver/fake/fake_resolver.c
@@ -0,0 +1,254 @@
+//
+// Copyright 2016 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+// This is similar to the sockaddr resolver, except that it supports a
+// bunch of query args that are useful for dependency injection in tests.
+
+#include <limits.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <grpc/support/alloc.h>
+#include <grpc/support/host_port.h>
+#include <grpc/support/port_platform.h>
+#include <grpc/support/string_util.h>
+
+#include "src/core/ext/filters/client_channel/lb_policy_factory.h"
+#include "src/core/ext/filters/client_channel/parse_address.h"
+#include "src/core/ext/filters/client_channel/resolver_registry.h"
+#include "src/core/lib/channel/channel_args.h"
+#include "src/core/lib/iomgr/combiner.h"
+#include "src/core/lib/iomgr/resolve_address.h"
+#include "src/core/lib/iomgr/unix_sockets_posix.h"
+#include "src/core/lib/slice/slice_internal.h"
+#include "src/core/lib/slice/slice_string_helpers.h"
+#include "src/core/lib/support/string.h"
+
+#include "src/core/ext/filters/client_channel/resolver/fake/fake_resolver.h"
+
+//
+// fake_resolver
+//
+
+typedef struct {
+  // base class -- must be first
+  grpc_resolver base;
+
+  // passed-in parameters
+  grpc_channel_args* channel_args;
+
+  // If not NULL, the next set of resolution results to be returned to
+  // grpc_resolver_next_locked()'s closure.
+  grpc_channel_args* next_results;
+
+  // Results to use for the pretended re-resolution in
+  // fake_resolver_channel_saw_error_locked().
+  grpc_channel_args* results_upon_error;
+
+  // pending next completion, or NULL
+  grpc_closure* next_completion;
+  // target result address for next completion
+  grpc_channel_args** target_result;
+} fake_resolver;
+
+static void fake_resolver_destroy(grpc_exec_ctx* exec_ctx, grpc_resolver* gr) {
+  fake_resolver* r = (fake_resolver*)gr;
+  grpc_channel_args_destroy(exec_ctx, r->next_results);
+  grpc_channel_args_destroy(exec_ctx, r->results_upon_error);
+  grpc_channel_args_destroy(exec_ctx, r->channel_args);
+  gpr_free(r);
+}
+
+static void fake_resolver_shutdown_locked(grpc_exec_ctx* exec_ctx,
+                                          grpc_resolver* resolver) {
+  fake_resolver* r = (fake_resolver*)resolver;
+  if (r->next_completion != NULL) {
+    *r->target_result = NULL;
+    GRPC_CLOSURE_SCHED(
+        exec_ctx, r->next_completion,
+        GRPC_ERROR_CREATE_FROM_STATIC_STRING("Resolver Shutdown"));
+    r->next_completion = NULL;
+  }
+}
+
+static void fake_resolver_maybe_finish_next_locked(grpc_exec_ctx* exec_ctx,
+                                                   fake_resolver* r) {
+  if (r->next_completion != NULL && r->next_results != NULL) {
+    *r->target_result =
+        grpc_channel_args_union(r->next_results, r->channel_args);
+    grpc_channel_args_destroy(exec_ctx, r->next_results);
+    r->next_results = NULL;
+    GRPC_CLOSURE_SCHED(exec_ctx, r->next_completion, GRPC_ERROR_NONE);
+    r->next_completion = NULL;
+  }
+}
+
+static void fake_resolver_channel_saw_error_locked(grpc_exec_ctx* exec_ctx,
+                                                   grpc_resolver* resolver) {
+  fake_resolver* r = (fake_resolver*)resolver;
+  if (r->next_results == NULL && r->results_upon_error != NULL) {
+    // Pretend we re-resolved.
+    r->next_results = grpc_channel_args_copy(r->results_upon_error);
+  }
+  fake_resolver_maybe_finish_next_locked(exec_ctx, r);
+}
+
+static void fake_resolver_next_locked(grpc_exec_ctx* exec_ctx,
+                                      grpc_resolver* resolver,
+                                      grpc_channel_args** target_result,
+                                      grpc_closure* on_complete) {
+  fake_resolver* r = (fake_resolver*)resolver;
+  GPR_ASSERT(!r->next_completion);
+  r->next_completion = on_complete;
+  r->target_result = target_result;
+  fake_resolver_maybe_finish_next_locked(exec_ctx, r);
+}
+
+static const grpc_resolver_vtable fake_resolver_vtable = {
+    fake_resolver_destroy, fake_resolver_shutdown_locked,
+    fake_resolver_channel_saw_error_locked, fake_resolver_next_locked};
+
+struct grpc_fake_resolver_response_generator {
+  fake_resolver* resolver;  // Set by the fake_resolver constructor to itself.
+  grpc_channel_args* next_response;
+  gpr_refcount refcount;
+};
+
+grpc_fake_resolver_response_generator*
+grpc_fake_resolver_response_generator_create() {
+  grpc_fake_resolver_response_generator* generator =
+      (grpc_fake_resolver_response_generator*)gpr_zalloc(sizeof(*generator));
+  gpr_ref_init(&generator->refcount, 1);
+  return generator;
+}
+
+grpc_fake_resolver_response_generator*
+grpc_fake_resolver_response_generator_ref(
+    grpc_fake_resolver_response_generator* generator) {
+  gpr_ref(&generator->refcount);
+  return generator;
+}
+
+void grpc_fake_resolver_response_generator_unref(
+    grpc_fake_resolver_response_generator* generator) {
+  if (gpr_unref(&generator->refcount)) {
+    gpr_free(generator);
+  }
+}
+
+static void set_response_cb(grpc_exec_ctx* exec_ctx, void* arg,
+                            grpc_error* error) {
+  grpc_fake_resolver_response_generator* generator =
+      (grpc_fake_resolver_response_generator*)arg;
+  fake_resolver* r = generator->resolver;
+  if (r->next_results != NULL) {
+    grpc_channel_args_destroy(exec_ctx, r->next_results);
+  }
+  r->next_results = generator->next_response;
+  if (r->results_upon_error != NULL) {
+    grpc_channel_args_destroy(exec_ctx, r->results_upon_error);
+  }
+  r->results_upon_error = grpc_channel_args_copy(generator->next_response);
+  fake_resolver_maybe_finish_next_locked(exec_ctx, r);
+}
+
+void grpc_fake_resolver_response_generator_set_response(
+    grpc_exec_ctx* exec_ctx, grpc_fake_resolver_response_generator* generator,
+    grpc_channel_args* next_response) {
+  GPR_ASSERT(generator->resolver != NULL);
+  generator->next_response = grpc_channel_args_copy(next_response);
+  GRPC_CLOSURE_SCHED(
+      exec_ctx, GRPC_CLOSURE_CREATE(set_response_cb, generator,
+                                    grpc_combiner_scheduler(
+                                        generator->resolver->base.combiner)),
+      GRPC_ERROR_NONE);
+}
+
+static void* response_generator_arg_copy(void* p) {
+  return grpc_fake_resolver_response_generator_ref(
+      (grpc_fake_resolver_response_generator*)p);
+}
+
+static void response_generator_arg_destroy(grpc_exec_ctx* exec_ctx, void* p) {
+  grpc_fake_resolver_response_generator_unref(
+      (grpc_fake_resolver_response_generator*)p);
+}
+
+static int response_generator_cmp(void* a, void* b) { return GPR_ICMP(a, b); }
+
+static const grpc_arg_pointer_vtable response_generator_arg_vtable = {
+    response_generator_arg_copy, response_generator_arg_destroy,
+    response_generator_cmp};
+
+grpc_arg grpc_fake_resolver_response_generator_arg(
+    grpc_fake_resolver_response_generator* generator) {
+  grpc_arg arg;
+  arg.type = GRPC_ARG_POINTER;
+  arg.key = GRPC_ARG_FAKE_RESOLVER_RESPONSE_GENERATOR;
+  arg.value.pointer.p = generator;
+  arg.value.pointer.vtable = &response_generator_arg_vtable;
+  return arg;
+}
+
+grpc_fake_resolver_response_generator*
+grpc_fake_resolver_get_response_generator(const grpc_channel_args* args) {
+  const grpc_arg* arg =
+      grpc_channel_args_find(args, GRPC_ARG_FAKE_RESOLVER_RESPONSE_GENERATOR);
+  if (arg == NULL || arg->type != GRPC_ARG_POINTER) return NULL;
+  return (grpc_fake_resolver_response_generator*)arg->value.pointer.p;
+}
+
+//
+// fake_resolver_factory
+//
+
+static void fake_resolver_factory_ref(grpc_resolver_factory* factory) {}
+
+static void fake_resolver_factory_unref(grpc_resolver_factory* factory) {}
+
+static grpc_resolver* fake_resolver_create(grpc_exec_ctx* exec_ctx,
+                                           grpc_resolver_factory* factory,
+                                           grpc_resolver_args* args) {
+  fake_resolver* r = (fake_resolver*)gpr_zalloc(sizeof(*r));
+  r->channel_args = grpc_channel_args_copy(args->args);
+  grpc_resolver_init(&r->base, &fake_resolver_vtable, args->combiner);
+  grpc_fake_resolver_response_generator* response_generator =
+      grpc_fake_resolver_get_response_generator(args->args);
+  if (response_generator != NULL) response_generator->resolver = r;
+  return &r->base;
+}
+
+static char* fake_resolver_get_default_authority(grpc_resolver_factory* factory,
+                                                 grpc_uri* uri) {
+  const char* path = uri->path;
+  if (path[0] == '/') ++path;
+  return gpr_strdup(path);
+}
+
+static const grpc_resolver_factory_vtable fake_resolver_factory_vtable = {
+    fake_resolver_factory_ref, fake_resolver_factory_unref,
+    fake_resolver_create, fake_resolver_get_default_authority, "fake"};
+
+static grpc_resolver_factory fake_resolver_factory = {
+    &fake_resolver_factory_vtable};
+
+void grpc_resolver_fake_init(void) {
+  grpc_register_resolver_type(&fake_resolver_factory);
+}
+
+void grpc_resolver_fake_shutdown(void) {}
diff --git a/src/core/ext/filters/client_channel/resolver/fake/fake_resolver.h b/src/core/ext/filters/client_channel/resolver/fake/fake_resolver.h
new file mode 100644
index 0000000000..c084ef2a58
--- /dev/null
+++ b/src/core/ext/filters/client_channel/resolver/fake/fake_resolver.h
@@ -0,0 +1,60 @@
+//
+// Copyright 2016 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#ifndef GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_RESOLVER_FAKE_FAKE_RESOLVER_H
+#define GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_RESOLVER_FAKE_FAKE_RESOLVER_H
+
+#include "src/core/ext/filters/client_channel/lb_policy_factory.h"
+#include "src/core/ext/filters/client_channel/uri_parser.h"
+#include "src/core/lib/channel/channel_args.h"
+
+#define GRPC_ARG_FAKE_RESOLVER_RESPONSE_GENERATOR \
+  "grpc.fake_resolver.response_generator"
+
+void grpc_resolver_fake_init();
+
+// Instances of \a grpc_fake_resolver_response_generator are passed to the
+// fake resolver in a channel argument (see \a
+// grpc_fake_resolver_response_generator_arg) in order to inject and trigger
+// custom resolutions. See also \a
+// grpc_fake_resolver_response_generator_set_response.
+typedef struct grpc_fake_resolver_response_generator
+    grpc_fake_resolver_response_generator;
+grpc_fake_resolver_response_generator*
+grpc_fake_resolver_response_generator_create();
+
+// Instruct the fake resolver associated with the \a response_generator instance
+// to trigger a new resolution for \a uri and \a args.
+void grpc_fake_resolver_response_generator_set_response(
+    grpc_exec_ctx* exec_ctx, grpc_fake_resolver_response_generator* generator,
+    grpc_channel_args* next_response);
+
+// Return a \a grpc_arg for a \a grpc_fake_resolver_response_generator instance.
+grpc_arg grpc_fake_resolver_response_generator_arg(
+    grpc_fake_resolver_response_generator* generator);
+// Return the \a grpc_fake_resolver_response_generator instance in \a args or
+// NULL.
+grpc_fake_resolver_response_generator*
+grpc_fake_resolver_get_response_generator(const grpc_channel_args* args);
+
+grpc_fake_resolver_response_generator*
+grpc_fake_resolver_response_generator_ref(
+    grpc_fake_resolver_response_generator* generator);
+void grpc_fake_resolver_response_generator_unref(
+    grpc_fake_resolver_response_generator* generator);
+
+#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_RESOLVER_FAKE_FAKE_RESOLVER_H \
+          */
diff --git a/src/core/ext/filters/client_channel/resolver/sockaddr/sockaddr_resolver.c b/src/core/ext/filters/client_channel/resolver/sockaddr/sockaddr_resolver.c
index 4d7d878c23..7ceb8f40a1 100644
--- a/src/core/ext/filters/client_channel/resolver/sockaddr/sockaddr_resolver.c
+++ b/src/core/ext/filters/client_channel/resolver/sockaddr/sockaddr_resolver.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015-2016, Google Inc.
- * All rights reserved.
+ * Copyright 2015-2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -88,7 +73,9 @@ static void sockaddr_shutdown_locked(grpc_exec_ctx *exec_ctx,
   sockaddr_resolver *r = (sockaddr_resolver *)resolver;
   if (r->next_completion != NULL) {
     *r->target_result = NULL;
-    grpc_closure_sched(exec_ctx, r->next_completion, GRPC_ERROR_NONE);
+    GRPC_CLOSURE_SCHED(
+        exec_ctx, r->next_completion,
+        GRPC_ERROR_CREATE_FROM_STATIC_STRING("Resolver Shutdown"));
     r->next_completion = NULL;
   }
 }
@@ -118,7 +105,7 @@ static void sockaddr_maybe_finish_next_locked(grpc_exec_ctx *exec_ctx,
     grpc_arg arg = grpc_lb_addresses_create_channel_arg(r->addresses);
     *r->target_result =
         grpc_channel_args_copy_and_add(r->channel_args, &arg, 1);
-    grpc_closure_sched(exec_ctx, r->next_completion, GRPC_ERROR_NONE);
+    GRPC_CLOSURE_SCHED(exec_ctx, r->next_completion, GRPC_ERROR_NONE);
     r->next_completion = NULL;
   }
 }
@@ -190,7 +177,8 @@ static grpc_resolver *sockaddr_create(grpc_exec_ctx *exec_ctx,
     return NULL;
   }
   /* Instantiate resolver. */
-  sockaddr_resolver *r = gpr_zalloc(sizeof(sockaddr_resolver));
+  sockaddr_resolver *r =
+      (sockaddr_resolver *)gpr_zalloc(sizeof(sockaddr_resolver));
   r->addresses = addresses;
   r->channel_args = grpc_channel_args_copy(args->args);
   grpc_resolver_init(&r->base, &sockaddr_resolver_vtable, args->combiner);
diff --git a/src/core/ext/filters/client_channel/resolver_factory.c b/src/core/ext/filters/client_channel/resolver_factory.c
index 07f9e4cf03..6f0a7c1e36 100644
--- a/src/core/ext/filters/client_channel/resolver_factory.c
+++ b/src/core/ext/filters/client_channel/resolver_factory.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/filters/client_channel/resolver_factory.h b/src/core/ext/filters/client_channel/resolver_factory.h
index f2fcfc06fe..6bd7929d4e 100644
--- a/src/core/ext/filters/client_channel/resolver_factory.h
+++ b/src/core/ext/filters/client_channel/resolver_factory.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/filters/client_channel/resolver_registry.c b/src/core/ext/filters/client_channel/resolver_registry.c
index fa997bd68f..1a0fb0bc3c 100644
--- a/src/core/ext/filters/client_channel/resolver_registry.c
+++ b/src/core/ext/filters/client_channel/resolver_registry.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/filters/client_channel/resolver_registry.h b/src/core/ext/filters/client_channel/resolver_registry.h
index f2e9f9249c..692490543d 100644
--- a/src/core/ext/filters/client_channel/resolver_registry.h
+++ b/src/core/ext/filters/client_channel/resolver_registry.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/filters/client_channel/retry_throttle.c b/src/core/ext/filters/client_channel/retry_throttle.c
index dd78a17844..3009e21d49 100644
--- a/src/core/ext/filters/client_channel/retry_throttle.c
+++ b/src/core/ext/filters/client_channel/retry_throttle.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2017, Google Inc.
- * All rights reserved.
+ * Copyright 2017 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/filters/client_channel/retry_throttle.h b/src/core/ext/filters/client_channel/retry_throttle.h
index 640865cf90..bf99297e98 100644
--- a/src/core/ext/filters/client_channel/retry_throttle.h
+++ b/src/core/ext/filters/client_channel/retry_throttle.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2017, Google Inc.
- * All rights reserved.
+ * Copyright 2017 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/filters/client_channel/subchannel.c b/src/core/ext/filters/client_channel/subchannel.c
index ddc24f7c71..bdaf567d6a 100644
--- a/src/core/ext/filters/client_channel/subchannel.c
+++ b/src/core/ext/filters/client_channel/subchannel.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -155,25 +140,13 @@ struct grpc_subchannel_call {
 static void subchannel_connected(grpc_exec_ctx *exec_ctx, void *subchannel,
                                  grpc_error *error);
 
-#ifdef GRPC_STREAM_REFCOUNT_DEBUG
+#ifndef NDEBUG
 #define REF_REASON reason
-#define REF_LOG(name, p)                                                  \
-  gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG, "%s: %p   ref %d -> %d %s", \
-          (name), (p), (p)->refs.count, (p)->refs.count + 1, reason)
-#define UNREF_LOG(name, p)                                                \
-  gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG, "%s: %p unref %d -> %d %s", \
-          (name), (p), (p)->refs.count, (p)->refs.count - 1, reason)
 #define REF_MUTATE_EXTRA_ARGS \
   GRPC_SUBCHANNEL_REF_EXTRA_ARGS, const char *purpose
 #define REF_MUTATE_PURPOSE(x) , file, line, reason, x
 #else
 #define REF_REASON ""
-#define REF_LOG(name, p) \
-  do {                   \
-  } while (0)
-#define UNREF_LOG(name, p) \
-  do {                     \
-  } while (0)
 #define REF_MUTATE_EXTRA_ARGS
 #define REF_MUTATE_PURPOSE(x)
 #endif
@@ -215,6 +188,7 @@ static void subchannel_destroy(grpc_exec_ctx *exec_ctx, void *arg,
   grpc_connector_unref(exec_ctx, c->connector);
   grpc_pollset_set_destroy(exec_ctx, c->pollset_set);
   grpc_subchannel_key_destroy(exec_ctx, c->key);
+  gpr_mu_destroy(&c->mu);
   gpr_free(c);
 }
 
@@ -222,10 +196,12 @@ static gpr_atm ref_mutate(grpc_subchannel *c, gpr_atm delta,
                           int barrier REF_MUTATE_EXTRA_ARGS) {
   gpr_atm old_val = barrier ? gpr_atm_full_fetch_add(&c->ref_pair, delta)
                             : gpr_atm_no_barrier_fetch_add(&c->ref_pair, delta);
-#ifdef GRPC_STREAM_REFCOUNT_DEBUG
-  gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
-          "SUBCHANNEL: %p %s 0x%08" PRIxPTR " -> 0x%08" PRIxPTR " [%s]", c,
-          purpose, old_val, old_val + delta, reason);
+#ifndef NDEBUG
+  if (GRPC_TRACER_ON(grpc_trace_stream_refcount)) {
+    gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
+            "SUBCHANNEL: %p %12s 0x%" PRIxPTR " -> 0x%" PRIxPTR " [%s]", c,
+            purpose, old_val, old_val + delta, reason);
+  }
 #endif
   return old_val;
 }
@@ -283,6 +259,7 @@ static void disconnect(grpc_exec_ctx *exec_ctx, grpc_subchannel *c) {
 void grpc_subchannel_unref(grpc_exec_ctx *exec_ctx,
                            grpc_subchannel *c GRPC_SUBCHANNEL_REF_EXTRA_ARGS) {
   gpr_atm old_refs;
+  // add a weak ref and subtract a strong ref (atomically)
   old_refs = ref_mutate(c, (gpr_atm)1 - (gpr_atm)(1 << INTERNAL_REF_BITS),
                         1 REF_MUTATE_PURPOSE("STRONG_UNREF"));
   if ((old_refs & STRONG_REF_MASK) == (1 << INTERNAL_REF_BITS)) {
@@ -297,7 +274,7 @@ void grpc_subchannel_weak_unref(grpc_exec_ctx *exec_ctx,
   gpr_atm old_refs;
   old_refs = ref_mutate(c, -(gpr_atm)1, 1 REF_MUTATE_PURPOSE("WEAK_UNREF"));
   if (old_refs == 1) {
-    grpc_closure_sched(exec_ctx, grpc_closure_create(subchannel_destroy, c,
+    GRPC_CLOSURE_SCHED(exec_ctx, GRPC_CLOSURE_CREATE(subchannel_destroy, c,
                                                      grpc_schedule_on_exec_ctx),
                        GRPC_ERROR_NONE);
   }
@@ -306,7 +283,7 @@ void grpc_subchannel_weak_unref(grpc_exec_ctx *exec_ctx,
 grpc_subchannel *grpc_subchannel_create(grpc_exec_ctx *exec_ctx,
                                         grpc_connector *connector,
                                         const grpc_subchannel_args *args) {
-  grpc_subchannel_key *key = grpc_subchannel_key_create(connector, args);
+  grpc_subchannel_key *key = grpc_subchannel_key_create(args);
   grpc_subchannel *c = grpc_subchannel_index_find(exec_ctx, key);
   if (c) {
     grpc_subchannel_key_destroy(exec_ctx, key);
@@ -347,7 +324,7 @@ grpc_subchannel *grpc_subchannel_create(grpc_exec_ctx *exec_ctx,
   if (new_args != NULL) grpc_channel_args_destroy(exec_ctx, new_args);
   c->root_external_state_watcher.next = c->root_external_state_watcher.prev =
       &c->root_external_state_watcher;
-  grpc_closure_init(&c->connected, subchannel_connected, c,
+  GRPC_CLOSURE_INIT(&c->connected, subchannel_connected, c,
                     grpc_schedule_on_exec_ctx);
   grpc_connectivity_state_init(&c->state_tracker, GRPC_CHANNEL_IDLE,
                                "subchannel");
@@ -435,7 +412,7 @@ static void on_external_state_watcher_done(grpc_exec_ctx *exec_ctx, void *arg,
   gpr_mu_unlock(&w->subchannel->mu);
   GRPC_SUBCHANNEL_WEAK_UNREF(exec_ctx, w->subchannel, "external_state_watcher");
   gpr_free(w);
-  grpc_closure_run(exec_ctx, follow_up, GRPC_ERROR_REF(error));
+  GRPC_CLOSURE_RUN(exec_ctx, follow_up, GRPC_ERROR_REF(error));
 }
 
 static void on_alarm(grpc_exec_ctx *exec_ctx, void *arg, grpc_error *error) {
@@ -501,7 +478,7 @@ static void maybe_start_connecting_locked(grpc_exec_ctx *exec_ctx,
       gpr_log(GPR_INFO, "Retry in %" PRId64 ".%09d seconds",
               time_til_next.tv_sec, time_til_next.tv_nsec);
     }
-    grpc_closure_init(&c->on_alarm, on_alarm, c, grpc_schedule_on_exec_ctx);
+    GRPC_CLOSURE_INIT(&c->on_alarm, on_alarm, c, grpc_schedule_on_exec_ctx);
     grpc_timer_init(exec_ctx, &c->alarm, c->next_attempt, &c->on_alarm, now);
   }
 }
@@ -527,7 +504,7 @@ void grpc_subchannel_notify_on_state_change(
     w->subchannel = c;
     w->pollset_set = interested_parties;
     w->notify = notify;
-    grpc_closure_init(&w->closure, on_external_state_watcher_done, w,
+    GRPC_CLOSURE_INIT(&w->closure, on_external_state_watcher_done, w,
                       grpc_schedule_on_exec_ctx);
     if (interested_parties != NULL) {
       grpc_pollset_set_add_pollset_set(exec_ctx, c->pollset_set,
@@ -648,14 +625,13 @@ static bool publish_transport_locked(grpc_exec_ctx *exec_ctx,
   sw_subchannel = gpr_malloc(sizeof(*sw_subchannel));
   sw_subchannel->subchannel = c;
   sw_subchannel->connectivity_state = GRPC_CHANNEL_READY;
-  grpc_closure_init(&sw_subchannel->closure, subchannel_on_child_state_changed,
+  GRPC_CLOSURE_INIT(&sw_subchannel->closure, subchannel_on_child_state_changed,
                     sw_subchannel, grpc_schedule_on_exec_ctx);
 
   if (c->disconnected) {
     gpr_free(sw_subchannel);
     grpc_channel_stack_destroy(exec_ctx, stk);
     gpr_free(con);
-    GRPC_SUBCHANNEL_WEAK_UNREF(exec_ctx, c, "connecting");
     return false;
   }
 
@@ -769,6 +745,11 @@ grpc_connected_subchannel *grpc_subchannel_get_connected_subchannel(
   return GET_CONNECTED_SUBCHANNEL(c, acq);
 }
 
+const grpc_subchannel_key *grpc_subchannel_get_key(
+    const grpc_subchannel *subchannel) {
+  return subchannel->key;
+}
+
 grpc_error *grpc_connected_subchannel_create_call(
     grpc_exec_ctx *exec_ctx, grpc_connected_subchannel *con,
     const grpc_connected_subchannel_call_args *args,
@@ -828,10 +809,7 @@ const char *grpc_get_subchannel_address_uri_arg(const grpc_channel_args *args) {
 }
 
 grpc_arg grpc_create_subchannel_address_arg(const grpc_resolved_address *addr) {
-  grpc_arg new_arg;
-  new_arg.key = GRPC_ARG_SUBCHANNEL_ADDRESS;
-  new_arg.type = GRPC_ARG_STRING;
-  new_arg.value.string =
-      addr->len > 0 ? grpc_sockaddr_to_uri(addr) : gpr_strdup("");
-  return new_arg;
+  return grpc_channel_arg_string_create(
+      GRPC_ARG_SUBCHANNEL_ADDRESS,
+      addr->len > 0 ? grpc_sockaddr_to_uri(addr) : gpr_strdup(""));
 }
diff --git a/src/core/ext/filters/client_channel/subchannel.h b/src/core/ext/filters/client_channel/subchannel.h
index e433c33e40..6d2abb04df 100644
--- a/src/core/ext/filters/client_channel/subchannel.h
+++ b/src/core/ext/filters/client_channel/subchannel.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -50,8 +35,9 @@ typedef struct grpc_subchannel grpc_subchannel;
 typedef struct grpc_connected_subchannel grpc_connected_subchannel;
 typedef struct grpc_subchannel_call grpc_subchannel_call;
 typedef struct grpc_subchannel_args grpc_subchannel_args;
+typedef struct grpc_subchannel_key grpc_subchannel_key;
 
-#ifdef GRPC_STREAM_REFCOUNT_DEBUG
+#ifndef NDEBUG
 #define GRPC_SUBCHANNEL_REF(p, r) \
   grpc_subchannel_ref((p), __FILE__, __LINE__, (r))
 #define GRPC_SUBCHANNEL_REF_FROM_WEAK_REF(p, r) \
@@ -155,6 +141,10 @@ void grpc_connected_subchannel_ping(grpc_exec_ctx *exec_ctx,
 grpc_connected_subchannel *grpc_subchannel_get_connected_subchannel(
     grpc_subchannel *subchannel);
 
+/** return the subchannel index key for \a subchannel */
+const grpc_subchannel_key *grpc_subchannel_get_key(
+    const grpc_subchannel *subchannel);
+
 /** continue processing a transport op */
 void grpc_subchannel_call_process_op(grpc_exec_ctx *exec_ctx,
                                      grpc_subchannel_call *subchannel_call,
diff --git a/src/core/ext/filters/client_channel/subchannel_index.c b/src/core/ext/filters/client_channel/subchannel_index.c
index f6ef4a845e..a33ab950bf 100644
--- a/src/core/ext/filters/client_channel/subchannel_index.c
+++ b/src/core/ext/filters/client_channel/subchannel_index.c
@@ -1,33 +1,18 @@
 //
 //
-// Copyright 2016, Google Inc.
-// All rights reserved.
+// Copyright 2016 gRPC authors.
 //
-// Redistribution and use in source and binary forms, with or without
-// modification, are permitted provided that the following conditions are
-// met:
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
 //
-//     * Redistributions of source code must retain the above copyright
-// notice, this list of conditions and the following disclaimer.
-//     * Redistributions in binary form must reproduce the above
-// copyright notice, this list of conditions and the following disclaimer
-// in the documentation and/or other materials provided with the
-// distribution.
-//     * Neither the name of Google Inc. nor the names of its
-// contributors may be used to endorse or promote products derived from
-// this software without specific prior written permission.
+//     http://www.apache.org/licenses/LICENSE-2.0
 //
-// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
 //
 //
 
@@ -50,12 +35,13 @@ static gpr_avl g_subchannel_index;
 static gpr_mu g_mu;
 
 struct grpc_subchannel_key {
-  grpc_connector *connector;
   grpc_subchannel_args args;
 };
 
 GPR_TLS_DECL(subchannel_index_exec_ctx);
 
+static bool g_force_creation = false;
+
 static void enter_ctx(grpc_exec_ctx *exec_ctx) {
   GPR_ASSERT(gpr_tls_get(&subchannel_index_exec_ctx) == 0);
   gpr_tls_set(&subchannel_index_exec_ctx, (intptr_t)exec_ctx);
@@ -73,10 +59,9 @@ static grpc_exec_ctx *current_ctx() {
 }
 
 static grpc_subchannel_key *create_key(
-    grpc_connector *connector, const grpc_subchannel_args *args,
+    const grpc_subchannel_args *args,
     grpc_channel_args *(*copy_channel_args)(const grpc_channel_args *args)) {
   grpc_subchannel_key *k = gpr_malloc(sizeof(*k));
-  k->connector = grpc_connector_ref(connector);
   k->args.filter_count = args->filter_count;
   if (k->args.filter_count > 0) {
     k->args.filters =
@@ -91,19 +76,18 @@ static grpc_subchannel_key *create_key(
 }
 
 grpc_subchannel_key *grpc_subchannel_key_create(
-    grpc_connector *connector, const grpc_subchannel_args *args) {
-  return create_key(connector, args, grpc_channel_args_normalize);
+    const grpc_subchannel_args *args) {
+  return create_key(args, grpc_channel_args_normalize);
 }
 
 static grpc_subchannel_key *subchannel_key_copy(grpc_subchannel_key *k) {
-  return create_key(k->connector, &k->args, grpc_channel_args_copy);
+  return create_key(&k->args, grpc_channel_args_copy);
 }
 
-static int subchannel_key_compare(grpc_subchannel_key *a,
-                                  grpc_subchannel_key *b) {
-  int c = GPR_ICMP(a->connector, b->connector);
-  if (c != 0) return c;
-  c = GPR_ICMP(a->args.filter_count, b->args.filter_count);
+int grpc_subchannel_key_compare(const grpc_subchannel_key *a,
+                                const grpc_subchannel_key *b) {
+  if (g_force_creation) return false;
+  int c = GPR_ICMP(a->args.filter_count, b->args.filter_count);
   if (c != 0) return c;
   if (a->args.filter_count > 0) {
     c = memcmp(a->args.filters, b->args.filters,
@@ -115,7 +99,6 @@ static int subchannel_key_compare(grpc_subchannel_key *a,
 
 void grpc_subchannel_key_destroy(grpc_exec_ctx *exec_ctx,
                                  grpc_subchannel_key *k) {
-  grpc_connector_unref(exec_ctx, k->connector);
   gpr_free((grpc_channel_args *)k->args.filters);
   grpc_channel_args_destroy(exec_ctx, (grpc_channel_args *)k->args.args);
   gpr_free(k);
@@ -128,7 +111,7 @@ static void sck_avl_destroy(void *p) {
 static void *sck_avl_copy(void *p) { return subchannel_key_copy(p); }
 
 static long sck_avl_compare(void *a, void *b) {
-  return subchannel_key_compare(a, b);
+  return grpc_subchannel_key_compare(a, b);
 }
 
 static void scv_avl_destroy(void *p) {
@@ -183,8 +166,11 @@ grpc_subchannel *grpc_subchannel_index_register(grpc_exec_ctx *exec_ctx,
   enter_ctx(exec_ctx);
 
   grpc_subchannel *c = NULL;
+  bool need_to_unref_constructed;
 
   while (c == NULL) {
+    need_to_unref_constructed = false;
+
     // Compare and swap loop:
     // - take a reference to the current index
     gpr_mu_lock(&g_mu);
@@ -194,8 +180,11 @@ grpc_subchannel *grpc_subchannel_index_register(grpc_exec_ctx *exec_ctx,
     // - Check to see if a subchannel already exists
     c = gpr_avl_get(index, key);
     if (c != NULL) {
+      c = GRPC_SUBCHANNEL_REF_FROM_WEAK_REF(c, "index_register");
+    }
+    if (c != NULL) {
       // yes -> we're done
-      GRPC_SUBCHANNEL_WEAK_UNREF(exec_ctx, constructed, "index_register");
+      need_to_unref_constructed = true;
     } else {
       // no -> update the avl and compare/swap
       gpr_avl updated =
@@ -219,6 +208,10 @@ grpc_subchannel *grpc_subchannel_index_register(grpc_exec_ctx *exec_ctx,
 
   leave_ctx(exec_ctx);
 
+  if (need_to_unref_constructed) {
+    GRPC_SUBCHANNEL_UNREF(exec_ctx, constructed, "index_register");
+  }
+
   return c;
 }
 
@@ -260,3 +253,7 @@ void grpc_subchannel_index_unregister(grpc_exec_ctx *exec_ctx,
 
   leave_ctx(exec_ctx);
 }
+
+void grpc_subchannel_index_test_only_set_force_creation(bool force_creation) {
+  g_force_creation = force_creation;
+}
diff --git a/src/core/ext/filters/client_channel/subchannel_index.h b/src/core/ext/filters/client_channel/subchannel_index.h
index f673ade378..98d882a453 100644
--- a/src/core/ext/filters/client_channel/subchannel_index.h
+++ b/src/core/ext/filters/client_channel/subchannel_index.h
@@ -1,50 +1,32 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
 #ifndef GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_SUBCHANNEL_INDEX_H
 #define GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_SUBCHANNEL_INDEX_H
 
-#include "src/core/ext/filters/client_channel/connector.h"
 #include "src/core/ext/filters/client_channel/subchannel.h"
 
 /** \file Provides an index of active subchannels so that they can be
     shared amongst channels */
 
-typedef struct grpc_subchannel_key grpc_subchannel_key;
-
 /** Create a key that can be used to uniquely identify a subchannel */
 grpc_subchannel_key *grpc_subchannel_key_create(
-    grpc_connector *con, const grpc_subchannel_args *args);
+    const grpc_subchannel_args *args);
 
 /** Destroy a subchannel key */
 void grpc_subchannel_key_destroy(grpc_exec_ctx *exec_ctx,
@@ -69,9 +51,24 @@ void grpc_subchannel_index_unregister(grpc_exec_ctx *exec_ctx,
                                       grpc_subchannel_key *key,
                                       grpc_subchannel *constructed);
 
+int grpc_subchannel_key_compare(const grpc_subchannel_key *a,
+                                const grpc_subchannel_key *b);
+
 /** Initialize the subchannel index (global) */
 void grpc_subchannel_index_init(void);
 /** Shutdown the subchannel index (global) */
 void grpc_subchannel_index_shutdown(void);
 
+/** \em TEST ONLY.
+ * If \a force_creation is true, all key comparisons will be false, resulting in
+ * new subchannels always being created. Otherwise, the keys will be compared as
+ * usual.
+ *
+ * This function is *not* threadsafe on purpose: it should *only* be used in
+ * test code.
+ *
+ * Tests using this function \em MUST run tests with and without \a
+ * force_creation set. */
+void grpc_subchannel_index_test_only_set_force_creation(bool force_creation);
+
 #endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_SUBCHANNEL_INDEX_H */
diff --git a/src/core/ext/filters/client_channel/uri_parser.c b/src/core/ext/filters/client_channel/uri_parser.c
index b233d835cb..e841928760 100644
--- a/src/core/ext/filters/client_channel/uri_parser.c
+++ b/src/core/ext/filters/client_channel/uri_parser.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/filters/client_channel/uri_parser.h b/src/core/ext/filters/client_channel/uri_parser.h
index b889040b16..05ca2e00e4 100644
--- a/src/core/ext/filters/client_channel/uri_parser.h
+++ b/src/core/ext/filters/client_channel/uri_parser.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/filters/deadline/deadline_filter.c b/src/core/ext/filters/deadline/deadline_filter.c
index 2e03d16bf6..6789903c95 100644
--- a/src/core/ext/filters/deadline/deadline_filter.c
+++ b/src/core/ext/filters/deadline/deadline_filter.c
@@ -1,32 +1,17 @@
 //
-// Copyright 2016, Google Inc.
-// All rights reserved.
+// Copyright 2016 gRPC authors.
 //
-// Redistribution and use in source and binary forms, with or without
-// modification, are permitted provided that the following conditions are
-// met:
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
 //
-//     * Redistributions of source code must retain the above copyright
-// notice, this list of conditions and the following disclaimer.
-//     * Redistributions in binary form must reproduce the above
-// copyright notice, this list of conditions and the following disclaimer
-// in the documentation and/or other materials provided with the
-// distribution.
-//     * Neither the name of Google Inc. nor the names of its
-// contributors may be used to endorse or promote products derived from
-// this software without specific prior written permission.
+//     http://www.apache.org/licenses/LICENSE-2.0
 //
-// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
 //
 
 #include "src/core/ext/filters/deadline/deadline_filter.h"
@@ -52,8 +37,8 @@
 // Timer callback.
 static void timer_callback(grpc_exec_ctx* exec_ctx, void* arg,
                            grpc_error* error) {
-  grpc_call_element* elem = arg;
-  grpc_deadline_state* deadline_state = elem->call_data;
+  grpc_call_element* elem = (grpc_call_element*)arg;
+  grpc_deadline_state* deadline_state = (grpc_deadline_state*)elem->call_data;
   if (error != GRPC_ERROR_CANCELLED) {
     grpc_call_element_signal_error(
         exec_ctx, elem,
@@ -72,7 +57,7 @@ static void start_timer_if_needed(grpc_exec_ctx* exec_ctx,
   if (gpr_time_cmp(deadline, gpr_inf_future(GPR_CLOCK_MONOTONIC)) == 0) {
     return;
   }
-  grpc_deadline_state* deadline_state = elem->call_data;
+  grpc_deadline_state* deadline_state = (grpc_deadline_state*)elem->call_data;
   grpc_deadline_timer_state cur_state;
   grpc_closure* closure = NULL;
 retry:
@@ -89,7 +74,7 @@ retry:
         // If we've already created and destroyed a timer, we always create a
         // new closure: we have no other guarantee that the inlined closure is
         // not in use (it may hold a pending call to timer_callback)
-        closure = grpc_closure_create(timer_callback, elem,
+        closure = GRPC_CLOSURE_CREATE(timer_callback, elem,
                                       grpc_schedule_on_exec_ctx);
       } else {
         goto retry;
@@ -100,7 +85,7 @@ retry:
                           GRPC_DEADLINE_STATE_INITIAL,
                           GRPC_DEADLINE_STATE_PENDING)) {
         closure =
-            grpc_closure_init(&deadline_state->timer_callback, timer_callback,
+            GRPC_CLOSURE_INIT(&deadline_state->timer_callback, timer_callback,
                               elem, grpc_schedule_on_exec_ctx);
       } else {
         goto retry;
@@ -127,10 +112,10 @@ static void cancel_timer_if_needed(grpc_exec_ctx* exec_ctx,
 
 // Callback run when the call is complete.
 static void on_complete(grpc_exec_ctx* exec_ctx, void* arg, grpc_error* error) {
-  grpc_deadline_state* deadline_state = arg;
+  grpc_deadline_state* deadline_state = (grpc_deadline_state*)arg;
   cancel_timer_if_needed(exec_ctx, deadline_state);
   // Invoke the next callback.
-  grpc_closure_run(exec_ctx, deadline_state->next_on_complete,
+  GRPC_CLOSURE_RUN(exec_ctx, deadline_state->next_on_complete,
                    GRPC_ERROR_REF(error));
 }
 
@@ -138,7 +123,7 @@ static void on_complete(grpc_exec_ctx* exec_ctx, void* arg, grpc_error* error) {
 static void inject_on_complete_cb(grpc_deadline_state* deadline_state,
                                   grpc_transport_stream_op_batch* op) {
   deadline_state->next_on_complete = op->on_complete;
-  grpc_closure_init(&deadline_state->on_complete, on_complete, deadline_state,
+  GRPC_CLOSURE_INIT(&deadline_state->on_complete, on_complete, deadline_state,
                     grpc_schedule_on_exec_ctx);
   op->on_complete = &deadline_state->on_complete;
 }
@@ -160,7 +145,7 @@ static void start_timer_after_init(grpc_exec_ctx* exec_ctx, void* arg,
 void grpc_deadline_state_init(grpc_exec_ctx* exec_ctx, grpc_call_element* elem,
                               grpc_call_stack* call_stack,
                               gpr_timespec deadline) {
-  grpc_deadline_state* deadline_state = elem->call_data;
+  grpc_deadline_state* deadline_state = (grpc_deadline_state*)elem->call_data;
   deadline_state->call_stack = call_stack;
   // Deadline will always be infinite on servers, so the timer will only be
   // set on clients with a finite deadline.
@@ -176,21 +161,21 @@ void grpc_deadline_state_init(grpc_exec_ctx* exec_ctx, grpc_call_element* elem,
     struct start_timer_after_init_state* state = gpr_malloc(sizeof(*state));
     state->elem = elem;
     state->deadline = deadline;
-    grpc_closure_init(&state->closure, start_timer_after_init, state,
+    GRPC_CLOSURE_INIT(&state->closure, start_timer_after_init, state,
                       grpc_schedule_on_exec_ctx);
-    grpc_closure_sched(exec_ctx, &state->closure, GRPC_ERROR_NONE);
+    GRPC_CLOSURE_SCHED(exec_ctx, &state->closure, GRPC_ERROR_NONE);
   }
 }
 
 void grpc_deadline_state_destroy(grpc_exec_ctx* exec_ctx,
                                  grpc_call_element* elem) {
-  grpc_deadline_state* deadline_state = elem->call_data;
+  grpc_deadline_state* deadline_state = (grpc_deadline_state*)elem->call_data;
   cancel_timer_if_needed(exec_ctx, deadline_state);
 }
 
 void grpc_deadline_state_reset(grpc_exec_ctx* exec_ctx, grpc_call_element* elem,
                                gpr_timespec new_deadline) {
-  grpc_deadline_state* deadline_state = elem->call_data;
+  grpc_deadline_state* deadline_state = (grpc_deadline_state*)elem->call_data;
   cancel_timer_if_needed(exec_ctx, deadline_state);
   start_timer_if_needed(exec_ctx, elem, new_deadline);
 }
@@ -198,7 +183,7 @@ void grpc_deadline_state_reset(grpc_exec_ctx* exec_ctx, grpc_call_element* elem,
 void grpc_deadline_state_client_start_transport_stream_op_batch(
     grpc_exec_ctx* exec_ctx, grpc_call_element* elem,
     grpc_transport_stream_op_batch* op) {
-  grpc_deadline_state* deadline_state = elem->call_data;
+  grpc_deadline_state* deadline_state = (grpc_deadline_state*)elem->call_data;
   if (op->cancel_stream) {
     cancel_timer_if_needed(exec_ctx, deadline_state);
   } else {
@@ -271,8 +256,8 @@ static void client_start_transport_stream_op_batch(
 // Callback for receiving initial metadata on the server.
 static void recv_initial_metadata_ready(grpc_exec_ctx* exec_ctx, void* arg,
                                         grpc_error* error) {
-  grpc_call_element* elem = arg;
-  server_call_data* calld = elem->call_data;
+  grpc_call_element* elem = (grpc_call_element*)arg;
+  server_call_data* calld = (server_call_data*)elem->call_data;
   // Get deadline from metadata and start the timer if needed.
   start_timer_if_needed(exec_ctx, elem, calld->recv_initial_metadata->deadline);
   // Invoke the next callback.
@@ -284,7 +269,7 @@ static void recv_initial_metadata_ready(grpc_exec_ctx* exec_ctx, void* arg,
 static void server_start_transport_stream_op_batch(
     grpc_exec_ctx* exec_ctx, grpc_call_element* elem,
     grpc_transport_stream_op_batch* op) {
-  server_call_data* calld = elem->call_data;
+  server_call_data* calld = (server_call_data*)elem->call_data;
   if (op->cancel_stream) {
     cancel_timer_if_needed(exec_ctx, &calld->base.deadline_state);
   } else {
@@ -296,7 +281,7 @@ static void server_start_transport_stream_op_batch(
           op->payload->recv_initial_metadata.recv_initial_metadata_ready;
       calld->recv_initial_metadata =
           op->payload->recv_initial_metadata.recv_initial_metadata;
-      grpc_closure_init(&calld->recv_initial_metadata_ready,
+      GRPC_CLOSURE_INIT(&calld->recv_initial_metadata_ready,
                         recv_initial_metadata_ready, elem,
                         grpc_schedule_on_exec_ctx);
       op->payload->recv_initial_metadata.recv_initial_metadata_ready =
@@ -356,8 +341,8 @@ static bool maybe_add_deadline_filter(grpc_exec_ctx* exec_ctx,
                                       void* arg) {
   return grpc_deadline_checking_enabled(
              grpc_channel_stack_builder_get_channel_arguments(builder))
-             ? grpc_channel_stack_builder_prepend_filter(builder, arg, NULL,
-                                                         NULL)
+             ? grpc_channel_stack_builder_prepend_filter(
+                   builder, (const grpc_channel_filter*)arg, NULL, NULL)
              : true;
 }
 
diff --git a/src/core/ext/filters/deadline/deadline_filter.h b/src/core/ext/filters/deadline/deadline_filter.h
index 5050453fa1..420bf7065a 100644
--- a/src/core/ext/filters/deadline/deadline_filter.h
+++ b/src/core/ext/filters/deadline/deadline_filter.h
@@ -1,32 +1,17 @@
 //
-// Copyright 2016, Google Inc.
-// All rights reserved.
+// Copyright 2016 gRPC authors.
 //
-// Redistribution and use in source and binary forms, with or without
-// modification, are permitted provided that the following conditions are
-// met:
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
 //
-//     * Redistributions of source code must retain the above copyright
-// notice, this list of conditions and the following disclaimer.
-//     * Redistributions in binary form must reproduce the above
-// copyright notice, this list of conditions and the following disclaimer
-// in the documentation and/or other materials provided with the
-// distribution.
-//     * Neither the name of Google Inc. nor the names of its
-// contributors may be used to endorse or promote products derived from
-// this software without specific prior written permission.
+//     http://www.apache.org/licenses/LICENSE-2.0
 //
-// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
 //
 
 #ifndef GRPC_CORE_EXT_FILTERS_DEADLINE_DEADLINE_FILTER_H
diff --git a/src/core/ext/filters/http/client/http_client_filter.c b/src/core/ext/filters/http/client/http_client_filter.c
index d8ae080eee..90f0aed7a0 100644
--- a/src/core/ext/filters/http/client/http_client_filter.c
+++ b/src/core/ext/filters/http/client/http_client_filter.c
@@ -1,32 +1,17 @@
 /*
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -173,7 +158,7 @@ static void hc_on_recv_initial_metadata(grpc_exec_ctx *exec_ctx,
   } else {
     GRPC_ERROR_REF(error);
   }
-  grpc_closure_run(exec_ctx, calld->on_done_recv_initial_metadata, error);
+  GRPC_CLOSURE_RUN(exec_ctx, calld->on_done_recv_initial_metadata, error);
 }
 
 static void hc_on_recv_trailing_metadata(grpc_exec_ctx *exec_ctx,
@@ -186,7 +171,7 @@ static void hc_on_recv_trailing_metadata(grpc_exec_ctx *exec_ctx,
   } else {
     GRPC_ERROR_REF(error);
   }
-  grpc_closure_run(exec_ctx, calld->on_done_recv_trailing_metadata, error);
+  GRPC_CLOSURE_RUN(exec_ctx, calld->on_done_recv_trailing_metadata, error);
 }
 
 static void hc_on_complete(grpc_exec_ctx *exec_ctx, void *user_data,
@@ -460,17 +445,17 @@ static grpc_error *init_call_elem(grpc_exec_ctx *exec_ctx,
   calld->payload_bytes = NULL;
   calld->send_message_blocked = false;
   grpc_slice_buffer_init(&calld->slices);
-  grpc_closure_init(&calld->hc_on_recv_initial_metadata,
+  GRPC_CLOSURE_INIT(&calld->hc_on_recv_initial_metadata,
                     hc_on_recv_initial_metadata, elem,
                     grpc_schedule_on_exec_ctx);
-  grpc_closure_init(&calld->hc_on_recv_trailing_metadata,
+  GRPC_CLOSURE_INIT(&calld->hc_on_recv_trailing_metadata,
                     hc_on_recv_trailing_metadata, elem,
                     grpc_schedule_on_exec_ctx);
-  grpc_closure_init(&calld->hc_on_complete, hc_on_complete, elem,
+  GRPC_CLOSURE_INIT(&calld->hc_on_complete, hc_on_complete, elem,
                     grpc_schedule_on_exec_ctx);
-  grpc_closure_init(&calld->got_slice, got_slice, elem,
+  GRPC_CLOSURE_INIT(&calld->got_slice, got_slice, elem,
                     grpc_schedule_on_exec_ctx);
-  grpc_closure_init(&calld->send_done, send_done, elem,
+  GRPC_CLOSURE_INIT(&calld->send_done, send_done, elem,
                     grpc_schedule_on_exec_ctx);
   return GRPC_ERROR_NONE;
 }
diff --git a/src/core/ext/filters/http/client/http_client_filter.h b/src/core/ext/filters/http/client/http_client_filter.h
index 6e1eb3937b..ec8177c436 100644
--- a/src/core/ext/filters/http/client/http_client_filter.h
+++ b/src/core/ext/filters/http/client/http_client_filter.h
@@ -1,32 +1,17 @@
 /*
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/filters/http/http_filters_plugin.c b/src/core/ext/filters/http/http_filters_plugin.c
index 856a7dbd91..a5c1b92054 100644
--- a/src/core/ext/filters/http/http_filters_plugin.c
+++ b/src/core/ext/filters/http/http_filters_plugin.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2017, Google Inc.
- * All rights reserved.
+ * Copyright 2017 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -80,7 +65,7 @@ static bool maybe_add_required_filter(grpc_exec_ctx *exec_ctx,
 }
 
 void grpc_http_filters_init(void) {
-  grpc_register_tracer("compression", &grpc_compression_trace);
+  grpc_register_tracer(&grpc_compression_trace);
   grpc_channel_init_register_stage(GRPC_CLIENT_SUBCHANNEL,
                                    GRPC_CHANNEL_INIT_BUILTIN_PRIORITY,
                                    maybe_add_optional_filter, &compress_filter);
diff --git a/src/core/ext/filters/http/message_compress/message_compress_filter.c b/src/core/ext/filters/http/message_compress/message_compress_filter.c
index 5a54a6ed15..71a8bc5bec 100644
--- a/src/core/ext/filters/http/message_compress/message_compress_filter.c
+++ b/src/core/ext/filters/http/message_compress/message_compress_filter.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -270,6 +255,23 @@ static void continue_send_message(grpc_exec_ctx *exec_ctx,
   }
 }
 
+static void handle_send_message_batch(grpc_exec_ctx *exec_ctx,
+                                      grpc_call_element *elem,
+                                      grpc_transport_stream_op_batch *op,
+                                      bool has_compression_algorithm) {
+  call_data *calld = elem->call_data;
+  if (!skip_compression(elem, op->payload->send_message.send_message->flags,
+                        has_compression_algorithm)) {
+    calld->send_op = op;
+    calld->send_length = op->payload->send_message.send_message->length;
+    calld->send_flags = op->payload->send_message.send_message->flags;
+    continue_send_message(exec_ctx, elem);
+  } else {
+    /* pass control down the stack */
+    grpc_call_next_op(exec_ctx, elem, op);
+  }
+}
+
 static void compress_start_transport_stream_op_batch(
     grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
     grpc_transport_stream_op_batch *op) {
@@ -322,8 +324,9 @@ static void compress_start_transport_stream_op_batch(
         goto retry_send_im;
       }
       if (cur != INITIAL_METADATA_UNSEEN) {
-        grpc_call_next_op(exec_ctx, elem,
-                          (grpc_transport_stream_op_batch *)cur);
+        handle_send_message_batch(exec_ctx, elem,
+                                  (grpc_transport_stream_op_batch *)cur,
+                                  has_compression_algorithm);
       }
     }
   }
@@ -340,17 +343,8 @@ static void compress_start_transport_stream_op_batch(
         break;
       case HAS_COMPRESSION_ALGORITHM:
       case NO_COMPRESSION_ALGORITHM:
-        if (!skip_compression(elem,
-                              op->payload->send_message.send_message->flags,
-                              cur == HAS_COMPRESSION_ALGORITHM)) {
-          calld->send_op = op;
-          calld->send_length = op->payload->send_message.send_message->length;
-          calld->send_flags = op->payload->send_message.send_message->flags;
-          continue_send_message(exec_ctx, elem);
-        } else {
-          /* pass control down the stack */
-          grpc_call_next_op(exec_ctx, elem, op);
-        }
+        handle_send_message_batch(exec_ctx, elem, op,
+                                  cur == HAS_COMPRESSION_ALGORITHM);
         break;
       default:
         if (cur & CANCELLED_BIT) {
@@ -379,9 +373,9 @@ static grpc_error *init_call_elem(grpc_exec_ctx *exec_ctx,
 
   /* initialize members */
   grpc_slice_buffer_init(&calld->slices);
-  grpc_closure_init(&calld->got_slice, got_slice, elem,
+  GRPC_CLOSURE_INIT(&calld->got_slice, got_slice, elem,
                     grpc_schedule_on_exec_ctx);
-  grpc_closure_init(&calld->send_done, send_done, elem,
+  GRPC_CLOSURE_INIT(&calld->send_done, send_done, elem,
                     grpc_schedule_on_exec_ctx);
 
   return GRPC_ERROR_NONE;
diff --git a/src/core/ext/filters/http/message_compress/message_compress_filter.h b/src/core/ext/filters/http/message_compress/message_compress_filter.h
index 135da4da62..c121a391eb 100644
--- a/src/core/ext/filters/http/message_compress/message_compress_filter.h
+++ b/src/core/ext/filters/http/message_compress/message_compress_filter.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/filters/http/server/http_server_filter.c b/src/core/ext/filters/http/server/http_server_filter.c
index 9e495f4d42..b145f12aff 100644
--- a/src/core/ext/filters/http/server/http_server_filter.c
+++ b/src/core/ext/filters/http/server/http_server_filter.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -284,7 +269,7 @@ static void hs_on_recv(grpc_exec_ctx *exec_ctx, void *user_data,
   } else {
     GRPC_ERROR_REF(err);
   }
-  grpc_closure_run(exec_ctx, calld->on_done_recv, err);
+  GRPC_CLOSURE_RUN(exec_ctx, calld->on_done_recv, err);
 }
 
 static void hs_on_complete(grpc_exec_ctx *exec_ctx, void *user_data,
@@ -296,11 +281,11 @@ static void hs_on_complete(grpc_exec_ctx *exec_ctx, void *user_data,
     *calld->pp_recv_message = calld->payload_bin_delivered
                                   ? NULL
                                   : (grpc_byte_stream *)&calld->read_stream;
-    grpc_closure_run(exec_ctx, calld->recv_message_ready, GRPC_ERROR_REF(err));
+    GRPC_CLOSURE_RUN(exec_ctx, calld->recv_message_ready, GRPC_ERROR_REF(err));
     calld->recv_message_ready = NULL;
     calld->payload_bin_delivered = true;
   }
-  grpc_closure_run(exec_ctx, calld->on_complete, GRPC_ERROR_REF(err));
+  GRPC_CLOSURE_RUN(exec_ctx, calld->on_complete, GRPC_ERROR_REF(err));
 }
 
 static void hs_recv_message_ready(grpc_exec_ctx *exec_ctx, void *user_data,
@@ -311,7 +296,7 @@ static void hs_recv_message_ready(grpc_exec_ctx *exec_ctx, void *user_data,
     /* do nothing. This is probably a GET request, and payload will be returned
     in hs_on_complete callback. */
   } else {
-    grpc_closure_run(exec_ctx, calld->recv_message_ready, GRPC_ERROR_REF(err));
+    GRPC_CLOSURE_RUN(exec_ctx, calld->recv_message_ready, GRPC_ERROR_REF(err));
   }
 }
 
@@ -398,11 +383,11 @@ static grpc_error *init_call_elem(grpc_exec_ctx *exec_ctx,
   /* grab pointers to our data from the call element */
   call_data *calld = elem->call_data;
   /* initialize members */
-  grpc_closure_init(&calld->hs_on_recv, hs_on_recv, elem,
+  GRPC_CLOSURE_INIT(&calld->hs_on_recv, hs_on_recv, elem,
                     grpc_schedule_on_exec_ctx);
-  grpc_closure_init(&calld->hs_on_complete, hs_on_complete, elem,
+  GRPC_CLOSURE_INIT(&calld->hs_on_complete, hs_on_complete, elem,
                     grpc_schedule_on_exec_ctx);
-  grpc_closure_init(&calld->hs_recv_message_ready, hs_recv_message_ready, elem,
+  GRPC_CLOSURE_INIT(&calld->hs_recv_message_ready, hs_recv_message_ready, elem,
                     grpc_schedule_on_exec_ctx);
   grpc_slice_buffer_init(&calld->read_slice_buffer);
   return GRPC_ERROR_NONE;
diff --git a/src/core/ext/filters/http/server/http_server_filter.h b/src/core/ext/filters/http/server/http_server_filter.h
index 8a2b2196ae..c0f678a329 100644
--- a/src/core/ext/filters/http/server/http_server_filter.h
+++ b/src/core/ext/filters/http/server/http_server_filter.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/filters/load_reporting/load_reporting.c b/src/core/ext/filters/load_reporting/load_reporting.c
index 4e9d0937ae..9745763c91 100644
--- a/src/core/ext/filters/load_reporting/load_reporting.c
+++ b/src/core/ext/filters/load_reporting/load_reporting.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -65,11 +50,7 @@ static bool maybe_add_load_reporting_filter(grpc_exec_ctx *exec_ctx,
 }
 
 grpc_arg grpc_load_reporting_enable_arg() {
-  grpc_arg arg;
-  arg.type = GRPC_ARG_INTEGER;
-  arg.key = GRPC_ARG_ENABLE_LOAD_REPORTING;
-  arg.value.integer = 1;
-  return arg;
+  return grpc_channel_arg_integer_create(GRPC_ARG_ENABLE_LOAD_REPORTING, 1);
 }
 
 /* Plugin registration */
diff --git a/src/core/ext/filters/load_reporting/load_reporting.h b/src/core/ext/filters/load_reporting/load_reporting.h
index e05a9dcc71..fc04d2826a 100644
--- a/src/core/ext/filters/load_reporting/load_reporting.h
+++ b/src/core/ext/filters/load_reporting/load_reporting.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/filters/load_reporting/load_reporting_filter.c b/src/core/ext/filters/load_reporting/load_reporting_filter.c
index 75a9a56687..08474efb2e 100644
--- a/src/core/ext/filters/load_reporting/load_reporting_filter.c
+++ b/src/core/ext/filters/load_reporting/load_reporting_filter.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -105,7 +90,7 @@ static grpc_error *init_call_elem(grpc_exec_ctx *exec_ctx,
                                   const grpc_call_element_args *args) {
   call_data *calld = elem->call_data;
   calld->id = (intptr_t)args->call_stack;
-  grpc_closure_init(&calld->on_initial_md_ready, on_initial_md_ready, elem,
+  GRPC_CLOSURE_INIT(&calld->on_initial_md_ready, on_initial_md_ready, elem,
                     grpc_schedule_on_exec_ctx);
 
   /* TODO(dgq): do something with the data
diff --git a/src/core/ext/filters/load_reporting/load_reporting_filter.h b/src/core/ext/filters/load_reporting/load_reporting_filter.h
index da884a1479..1a5424e43a 100644
--- a/src/core/ext/filters/load_reporting/load_reporting_filter.h
+++ b/src/core/ext/filters/load_reporting/load_reporting_filter.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/filters/max_age/max_age_filter.c b/src/core/ext/filters/max_age/max_age_filter.c
index a9d91e2f80..7d748b9c32 100644
--- a/src/core/ext/filters/max_age/max_age_filter.c
+++ b/src/core/ext/filters/max_age/max_age_filter.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2017, Google Inc.
- * All rights reserved.
+ * Copyright 2017 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -123,7 +108,7 @@ static void decrease_call_count(grpc_exec_ctx* exec_ctx, channel_data* chand) {
 
 static void start_max_idle_timer_after_init(grpc_exec_ctx* exec_ctx, void* arg,
                                             grpc_error* error) {
-  channel_data* chand = arg;
+  channel_data* chand = (channel_data*)arg;
   /* Decrease call_count. If there are no active calls at this time,
      max_idle_timer will start here. If the number of active calls is not 0,
      max_idle_timer will start after all the active calls end. */
@@ -134,7 +119,7 @@ static void start_max_idle_timer_after_init(grpc_exec_ctx* exec_ctx, void* arg,
 
 static void start_max_age_timer_after_init(grpc_exec_ctx* exec_ctx, void* arg,
                                            grpc_error* error) {
-  channel_data* chand = arg;
+  channel_data* chand = (channel_data*)arg;
   gpr_mu_lock(&chand->max_age_timer_mu);
   chand->max_age_timer_pending = true;
   GRPC_CHANNEL_STACK_REF(chand->channel_stack, "max_age max_age_timer");
@@ -155,7 +140,7 @@ static void start_max_age_timer_after_init(grpc_exec_ctx* exec_ctx, void* arg,
 static void start_max_age_grace_timer_after_goaway_op(grpc_exec_ctx* exec_ctx,
                                                       void* arg,
                                                       grpc_error* error) {
-  channel_data* chand = arg;
+  channel_data* chand = (channel_data*)arg;
   gpr_mu_lock(&chand->max_age_timer_mu);
   chand->max_age_grace_timer_pending = true;
   GRPC_CHANNEL_STACK_REF(chand->channel_stack, "max_age max_age_grace_timer");
@@ -171,7 +156,7 @@ static void start_max_age_grace_timer_after_goaway_op(grpc_exec_ctx* exec_ctx,
 
 static void close_max_idle_channel(grpc_exec_ctx* exec_ctx, void* arg,
                                    grpc_error* error) {
-  channel_data* chand = arg;
+  channel_data* chand = (channel_data*)arg;
   if (error == GRPC_ERROR_NONE) {
     /* Prevent the max idle timer from being set again */
     gpr_atm_no_barrier_fetch_add(&chand->call_count, 1);
@@ -191,7 +176,7 @@ static void close_max_idle_channel(grpc_exec_ctx* exec_ctx, void* arg,
 
 static void close_max_age_channel(grpc_exec_ctx* exec_ctx, void* arg,
                                   grpc_error* error) {
-  channel_data* chand = arg;
+  channel_data* chand = (channel_data*)arg;
   gpr_mu_lock(&chand->max_age_timer_mu);
   chand->max_age_timer_pending = false;
   gpr_mu_unlock(&chand->max_age_timer_mu);
@@ -215,7 +200,7 @@ static void close_max_age_channel(grpc_exec_ctx* exec_ctx, void* arg,
 
 static void force_close_max_age_channel(grpc_exec_ctx* exec_ctx, void* arg,
                                         grpc_error* error) {
-  channel_data* chand = arg;
+  channel_data* chand = (channel_data*)arg;
   gpr_mu_lock(&chand->max_age_timer_mu);
   chand->max_age_grace_timer_pending = false;
   gpr_mu_unlock(&chand->max_age_timer_mu);
@@ -235,7 +220,7 @@ static void force_close_max_age_channel(grpc_exec_ctx* exec_ctx, void* arg,
 
 static void channel_connectivity_changed(grpc_exec_ctx* exec_ctx, void* arg,
                                          grpc_error* error) {
-  channel_data* chand = arg;
+  channel_data* chand = (channel_data*)arg;
   if (chand->connectivity_state != GRPC_CHANNEL_SHUTDOWN) {
     grpc_transport_op* op = grpc_make_transport_op(NULL);
     op->on_connectivity_state_change = &chand->channel_connectivity_changed,
@@ -279,7 +264,7 @@ static int add_random_max_connection_age_jitter(int value) {
 static grpc_error* init_call_elem(grpc_exec_ctx* exec_ctx,
                                   grpc_call_element* elem,
                                   const grpc_call_element_args* args) {
-  channel_data* chand = elem->channel_data;
+  channel_data* chand = (channel_data*)elem->channel_data;
   increase_call_count(exec_ctx, chand);
   return GRPC_ERROR_NONE;
 }
@@ -296,7 +281,7 @@ static void destroy_call_elem(grpc_exec_ctx* exec_ctx, grpc_call_element* elem,
 static grpc_error* init_channel_elem(grpc_exec_ctx* exec_ctx,
                                      grpc_channel_element* elem,
                                      grpc_channel_element_args* args) {
-  channel_data* chand = elem->channel_data;
+  channel_data* chand = (channel_data*)elem->channel_data;
   gpr_mu_init(&chand->max_age_timer_mu);
   chand->max_age_timer_pending = false;
   chand->max_age_grace_timer_pending = false;
@@ -344,23 +329,23 @@ static grpc_error* init_channel_elem(grpc_exec_ctx* exec_ctx,
                            : gpr_time_from_millis(value, GPR_TIMESPAN);
     }
   }
-  grpc_closure_init(&chand->close_max_idle_channel, close_max_idle_channel,
+  GRPC_CLOSURE_INIT(&chand->close_max_idle_channel, close_max_idle_channel,
                     chand, grpc_schedule_on_exec_ctx);
-  grpc_closure_init(&chand->close_max_age_channel, close_max_age_channel, chand,
+  GRPC_CLOSURE_INIT(&chand->close_max_age_channel, close_max_age_channel, chand,
                     grpc_schedule_on_exec_ctx);
-  grpc_closure_init(&chand->force_close_max_age_channel,
+  GRPC_CLOSURE_INIT(&chand->force_close_max_age_channel,
                     force_close_max_age_channel, chand,
                     grpc_schedule_on_exec_ctx);
-  grpc_closure_init(&chand->start_max_idle_timer_after_init,
+  GRPC_CLOSURE_INIT(&chand->start_max_idle_timer_after_init,
                     start_max_idle_timer_after_init, chand,
                     grpc_schedule_on_exec_ctx);
-  grpc_closure_init(&chand->start_max_age_timer_after_init,
+  GRPC_CLOSURE_INIT(&chand->start_max_age_timer_after_init,
                     start_max_age_timer_after_init, chand,
                     grpc_schedule_on_exec_ctx);
-  grpc_closure_init(&chand->start_max_age_grace_timer_after_goaway_op,
+  GRPC_CLOSURE_INIT(&chand->start_max_age_grace_timer_after_goaway_op,
                     start_max_age_grace_timer_after_goaway_op, chand,
                     grpc_schedule_on_exec_ctx);
-  grpc_closure_init(&chand->channel_connectivity_changed,
+  GRPC_CLOSURE_INIT(&chand->channel_connectivity_changed,
                     channel_connectivity_changed, chand,
                     grpc_schedule_on_exec_ctx);
 
@@ -375,7 +360,7 @@ static grpc_error* init_channel_elem(grpc_exec_ctx* exec_ctx,
        initialization is done. */
     GRPC_CHANNEL_STACK_REF(chand->channel_stack,
                            "max_age start_max_age_timer_after_init");
-    grpc_closure_sched(exec_ctx, &chand->start_max_age_timer_after_init,
+    GRPC_CLOSURE_SCHED(exec_ctx, &chand->start_max_age_timer_after_init,
                        GRPC_ERROR_NONE);
   }
 
@@ -386,7 +371,7 @@ static grpc_error* init_channel_elem(grpc_exec_ctx* exec_ctx,
       0) {
     GRPC_CHANNEL_STACK_REF(chand->channel_stack,
                            "max_age start_max_idle_timer_after_init");
-    grpc_closure_sched(exec_ctx, &chand->start_max_idle_timer_after_init,
+    GRPC_CLOSURE_SCHED(exec_ctx, &chand->start_max_idle_timer_after_init,
                        GRPC_ERROR_NONE);
   }
   return GRPC_ERROR_NONE;
diff --git a/src/core/ext/filters/max_age/max_age_filter.h b/src/core/ext/filters/max_age/max_age_filter.h
index ed2015297a..68fb4a4ca5 100644
--- a/src/core/ext/filters/max_age/max_age_filter.h
+++ b/src/core/ext/filters/max_age/max_age_filter.h
@@ -1,32 +1,17 @@
 //
-// Copyright 2017, Google Inc.
-// All rights reserved.
+// Copyright 2017 gRPC authors.
 //
-// Redistribution and use in source and binary forms, with or without
-// modification, are permitted provided that the following conditions are
-// met:
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
 //
-//     * Redistributions of source code must retain the above copyright
-// notice, this list of conditions and the following disclaimer.
-//     * Redistributions in binary form must reproduce the above
-// copyright notice, this list of conditions and the following disclaimer
-// in the documentation and/or other materials provided with the
-// distribution.
-//     * Neither the name of Google Inc. nor the names of its
-// contributors may be used to endorse or promote products derived from
-// this software without specific prior written permission.
+//     http://www.apache.org/licenses/LICENSE-2.0
 //
-// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
 //
 
 #ifndef GRPC_CORE_EXT_FILTERS_MAX_AGE_MAX_AGE_FILTER_H
diff --git a/src/core/ext/filters/message_size/message_size_filter.c b/src/core/ext/filters/message_size/message_size_filter.c
index b615116965..846c7df69a 100644
--- a/src/core/ext/filters/message_size/message_size_filter.c
+++ b/src/core/ext/filters/message_size/message_size_filter.c
@@ -1,32 +1,17 @@
 //
-// Copyright 2016, Google Inc.
-// All rights reserved.
+// Copyright 2016 gRPC authors.
 //
-// Redistribution and use in source and binary forms, with or without
-// modification, are permitted provided that the following conditions are
-// met:
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
 //
-//     * Redistributions of source code must retain the above copyright
-// notice, this list of conditions and the following disclaimer.
-//     * Redistributions in binary form must reproduce the above
-// copyright notice, this list of conditions and the following disclaimer
-// in the documentation and/or other materials provided with the
-// distribution.
-//     * Neither the name of Google Inc. nor the names of its
-// contributors may be used to endorse or promote products derived from
-// this software without specific prior written permission.
+//     http://www.apache.org/licenses/LICENSE-2.0
 //
-// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
 //
 
 #include "src/core/ext/filters/message_size/message_size_filter.h"
@@ -75,7 +60,8 @@ static void* message_size_limits_create_from_json(const grpc_json* json) {
       if (max_response_message_bytes == -1) return NULL;
     }
   }
-  message_size_limits* value = gpr_malloc(sizeof(message_size_limits));
+  message_size_limits* value =
+      (message_size_limits*)gpr_malloc(sizeof(message_size_limits));
   value->max_send_size = max_request_message_bytes;
   value->max_recv_size = max_response_message_bytes;
   return value;
@@ -103,8 +89,8 @@ typedef struct channel_data {
 // receive message size.
 static void recv_message_ready(grpc_exec_ctx* exec_ctx, void* user_data,
                                grpc_error* error) {
-  grpc_call_element* elem = user_data;
-  call_data* calld = elem->call_data;
+  grpc_call_element* elem = (grpc_call_element*)user_data;
+  call_data* calld = (call_data*)elem->call_data;
   if (*calld->recv_message != NULL && calld->limits.max_recv_size >= 0 &&
       (*calld->recv_message)->length > (size_t)calld->limits.max_recv_size) {
     char* message_string;
@@ -125,14 +111,14 @@ static void recv_message_ready(grpc_exec_ctx* exec_ctx, void* user_data,
     GRPC_ERROR_REF(error);
   }
   // Invoke the next callback.
-  grpc_closure_run(exec_ctx, calld->next_recv_message_ready, error);
+  GRPC_CLOSURE_RUN(exec_ctx, calld->next_recv_message_ready, error);
 }
 
 // Start transport stream op.
 static void start_transport_stream_op_batch(
     grpc_exec_ctx* exec_ctx, grpc_call_element* elem,
     grpc_transport_stream_op_batch* op) {
-  call_data* calld = elem->call_data;
+  call_data* calld = (call_data*)elem->call_data;
   // Check max send message size.
   if (op->send_message && calld->limits.max_send_size >= 0 &&
       op->payload->send_message.send_message->length >
@@ -164,10 +150,10 @@ static void start_transport_stream_op_batch(
 static grpc_error* init_call_elem(grpc_exec_ctx* exec_ctx,
                                   grpc_call_element* elem,
                                   const grpc_call_element_args* args) {
-  channel_data* chand = elem->channel_data;
-  call_data* calld = elem->call_data;
+  channel_data* chand = (channel_data*)elem->channel_data;
+  call_data* calld = (call_data*)elem->call_data;
   calld->next_recv_message_ready = NULL;
-  grpc_closure_init(&calld->recv_message_ready, recv_message_ready, elem,
+  GRPC_CLOSURE_INIT(&calld->recv_message_ready, recv_message_ready, elem,
                     grpc_schedule_on_exec_ctx);
   // Get max sizes from channel data, then merge in per-method config values.
   // Note: Per-method config is only available on the client, so we
@@ -175,8 +161,9 @@ static grpc_error* init_call_elem(grpc_exec_ctx* exec_ctx,
   // size to the receive limit.
   calld->limits = chand->limits;
   if (chand->method_limit_table != NULL) {
-    message_size_limits* limits = grpc_method_config_table_get(
-        exec_ctx, chand->method_limit_table, args->path);
+    message_size_limits* limits =
+        (message_size_limits*)grpc_method_config_table_get(
+            exec_ctx, chand->method_limit_table, args->path);
     if (limits != NULL) {
       if (limits->max_send_size >= 0 &&
           (limits->max_send_size < calld->limits.max_send_size ||
@@ -235,7 +222,7 @@ static grpc_error* init_channel_elem(grpc_exec_ctx* exec_ctx,
                                      grpc_channel_element* elem,
                                      grpc_channel_element_args* args) {
   GPR_ASSERT(!args->is_last);
-  channel_data* chand = elem->channel_data;
+  channel_data* chand = (channel_data*)elem->channel_data;
   chand->limits = get_message_size_limits(args->channel_args);
   // Get method config table from channel args.
   const grpc_arg* channel_arg =
@@ -258,7 +245,7 @@ static grpc_error* init_channel_elem(grpc_exec_ctx* exec_ctx,
 // Destructor for channel_data.
 static void destroy_channel_elem(grpc_exec_ctx* exec_ctx,
                                  grpc_channel_element* elem) {
-  channel_data* chand = elem->channel_data;
+  channel_data* chand = (channel_data*)elem->channel_data;
   grpc_slice_hash_table_unref(exec_ctx, chand->method_limit_table);
 }
 
diff --git a/src/core/ext/filters/message_size/message_size_filter.h b/src/core/ext/filters/message_size/message_size_filter.h
index 83980e738c..d3667f7003 100644
--- a/src/core/ext/filters/message_size/message_size_filter.h
+++ b/src/core/ext/filters/message_size/message_size_filter.h
@@ -1,32 +1,17 @@
 //
-// Copyright 2016, Google Inc.
-// All rights reserved.
+// Copyright 2016 gRPC authors.
 //
-// Redistribution and use in source and binary forms, with or without
-// modification, are permitted provided that the following conditions are
-// met:
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
 //
-//     * Redistributions of source code must retain the above copyright
-// notice, this list of conditions and the following disclaimer.
-//     * Redistributions in binary form must reproduce the above
-// copyright notice, this list of conditions and the following disclaimer
-// in the documentation and/or other materials provided with the
-// distribution.
-//     * Neither the name of Google Inc. nor the names of its
-// contributors may be used to endorse or promote products derived from
-// this software without specific prior written permission.
+//     http://www.apache.org/licenses/LICENSE-2.0
 //
-// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
 //
 
 #ifndef GRPC_CORE_EXT_FILTERS_MESSAGE_SIZE_MESSAGE_SIZE_FILTER_H
diff --git a/src/core/ext/filters/workarounds/workaround_cronet_compression_filter.c b/src/core/ext/filters/workarounds/workaround_cronet_compression_filter.c
new file mode 100644
index 0000000000..b4d2cb4b8c
--- /dev/null
+++ b/src/core/ext/filters/workarounds/workaround_cronet_compression_filter.c
@@ -0,0 +1,208 @@
+//
+// Copyright 2017 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#include "src/core/ext/filters/workarounds/workaround_cronet_compression_filter.h"
+
+#include <string.h>
+
+#include <grpc/support/alloc.h>
+
+#include "src/core/ext/filters/workarounds/workaround_utils.h"
+#include "src/core/lib/channel/channel_stack_builder.h"
+#include "src/core/lib/surface/channel_init.h"
+#include "src/core/lib/transport/metadata.h"
+
+typedef struct call_data {
+  // Receive closures are chained: we inject this closure as the
+  // recv_initial_metadata_ready up-call on transport_stream_op, and remember to
+  // call our next_recv_initial_metadata_ready member after handling it.
+  grpc_closure recv_initial_metadata_ready;
+  // Used by recv_initial_metadata_ready.
+  grpc_metadata_batch* recv_initial_metadata;
+  // Original recv_initial_metadata_ready callback, invoked after our own.
+  grpc_closure* next_recv_initial_metadata_ready;
+
+  // Marks whether the workaround is active
+  bool workaround_active;
+} call_data;
+
+// Find the user agent metadata element in the batch
+static bool get_user_agent_mdelem(const grpc_metadata_batch* batch,
+                                  grpc_mdelem* md) {
+  if (batch->idx.named.user_agent != NULL) {
+    *md = batch->idx.named.user_agent->md;
+    return true;
+  }
+  return false;
+}
+
+// Callback invoked when we receive an initial metadata.
+static void recv_initial_metadata_ready(grpc_exec_ctx* exec_ctx,
+                                        void* user_data, grpc_error* error) {
+  grpc_call_element* elem = (grpc_call_element*)user_data;
+  call_data* calld = (call_data*)elem->call_data;
+
+  if (GRPC_ERROR_NONE == error) {
+    grpc_mdelem md;
+    if (get_user_agent_mdelem(calld->recv_initial_metadata, &md)) {
+      grpc_workaround_user_agent_md* user_agent_md = grpc_parse_user_agent(md);
+      if (user_agent_md
+              ->workaround_active[GRPC_WORKAROUND_ID_CRONET_COMPRESSION]) {
+        calld->workaround_active = true;
+      }
+    }
+  }
+
+  // Invoke the next callback.
+  GRPC_CLOSURE_RUN(exec_ctx, calld->next_recv_initial_metadata_ready,
+                   GRPC_ERROR_REF(error));
+}
+
+// Start transport stream op.
+static void start_transport_stream_op_batch(
+    grpc_exec_ctx* exec_ctx, grpc_call_element* elem,
+    grpc_transport_stream_op_batch* op) {
+  call_data* calld = (call_data*)elem->call_data;
+
+  // Inject callback for receiving initial metadata
+  if (op->recv_initial_metadata) {
+    calld->next_recv_initial_metadata_ready =
+        op->payload->recv_initial_metadata.recv_initial_metadata_ready;
+    op->payload->recv_initial_metadata.recv_initial_metadata_ready =
+        &calld->recv_initial_metadata_ready;
+    calld->recv_initial_metadata =
+        op->payload->recv_initial_metadata.recv_initial_metadata;
+  }
+
+  if (op->send_message) {
+    /* Send message happens after client's user-agent (initial metadata) is
+     * received, so workaround_active must be set already */
+    if (calld->workaround_active) {
+      op->payload->send_message.send_message->flags |= GRPC_WRITE_NO_COMPRESS;
+    }
+  }
+
+  // Chain to the next filter.
+  grpc_call_next_op(exec_ctx, elem, op);
+}
+
+// Constructor for call_data.
+static grpc_error* init_call_elem(grpc_exec_ctx* exec_ctx,
+                                  grpc_call_element* elem,
+                                  const grpc_call_element_args* args) {
+  call_data* calld = (call_data*)elem->call_data;
+  calld->next_recv_initial_metadata_ready = NULL;
+  calld->workaround_active = false;
+  GRPC_CLOSURE_INIT(&calld->recv_initial_metadata_ready,
+                    recv_initial_metadata_ready, elem,
+                    grpc_schedule_on_exec_ctx);
+  return GRPC_ERROR_NONE;
+}
+
+// Destructor for call_data.
+static void destroy_call_elem(grpc_exec_ctx* exec_ctx, grpc_call_element* elem,
+                              const grpc_call_final_info* final_info,
+                              grpc_closure* ignored) {}
+
+// Constructor for channel_data.
+static grpc_error* init_channel_elem(grpc_exec_ctx* exec_ctx,
+                                     grpc_channel_element* elem,
+                                     grpc_channel_element_args* args) {
+  return GRPC_ERROR_NONE;
+}
+
+// Destructor for channel_data.
+static void destroy_channel_elem(grpc_exec_ctx* exec_ctx,
+                                 grpc_channel_element* elem) {}
+
+// Parse the user agent
+static bool parse_user_agent(grpc_mdelem md) {
+  const char grpc_objc_specifier[] = "grpc-objc/";
+  const size_t grpc_objc_specifier_len = sizeof(grpc_objc_specifier) - 1;
+  const char cronet_specifier[] = "cronet_http";
+  const size_t cronet_specifier_len = sizeof(cronet_specifier) - 1;
+
+  char* user_agent_str = grpc_slice_to_c_string(GRPC_MDVALUE(md));
+  bool grpc_objc_specifier_seen = false;
+  bool cronet_specifier_seen = false;
+  char *major_version_str = user_agent_str, *minor_version_str;
+  long major_version, minor_version;
+
+  char* head = strtok(user_agent_str, " ");
+  while (head != NULL) {
+    if (!grpc_objc_specifier_seen &&
+        0 == strncmp(head, grpc_objc_specifier, grpc_objc_specifier_len)) {
+      major_version_str = head + grpc_objc_specifier_len;
+      grpc_objc_specifier_seen = true;
+    } else if (grpc_objc_specifier_seen &&
+               0 == strncmp(head, cronet_specifier, cronet_specifier_len)) {
+      cronet_specifier_seen = true;
+      break;
+    }
+
+    head = strtok(NULL, " ");
+  }
+  if (grpc_objc_specifier_seen) {
+    major_version_str = strtok(major_version_str, ".");
+    minor_version_str = strtok(NULL, ".");
+    major_version = atol(major_version_str);
+    minor_version = atol(minor_version_str);
+  }
+
+  gpr_free(user_agent_str);
+  return (grpc_objc_specifier_seen && cronet_specifier_seen &&
+          (major_version < 1 || (major_version == 1 && minor_version <= 3)));
+}
+
+const grpc_channel_filter grpc_workaround_cronet_compression_filter = {
+    start_transport_stream_op_batch,
+    grpc_channel_next_op,
+    sizeof(call_data),
+    init_call_elem,
+    grpc_call_stack_ignore_set_pollset_or_pollset_set,
+    destroy_call_elem,
+    0,
+    init_channel_elem,
+    destroy_channel_elem,
+    grpc_call_next_get_peer,
+    grpc_channel_next_get_info,
+    "workaround_cronet_compression"};
+
+static bool register_workaround_cronet_compression(
+    grpc_exec_ctx* exec_ctx, grpc_channel_stack_builder* builder, void* arg) {
+  const grpc_channel_args* channel_args =
+      grpc_channel_stack_builder_get_channel_arguments(builder);
+  const grpc_arg* a = grpc_channel_args_find(
+      channel_args, GRPC_ARG_WORKAROUND_CRONET_COMPRESSION);
+  if (a == NULL) {
+    return true;
+  }
+  if (grpc_channel_arg_get_bool(a, false) == false) {
+    return true;
+  }
+  return grpc_channel_stack_builder_prepend_filter(
+      builder, &grpc_workaround_cronet_compression_filter, NULL, NULL);
+}
+
+void grpc_workaround_cronet_compression_filter_init(void) {
+  grpc_channel_init_register_stage(
+      GRPC_SERVER_CHANNEL, GRPC_WORKAROUND_PRIORITY_HIGH,
+      register_workaround_cronet_compression, NULL);
+  grpc_register_workaround(GRPC_WORKAROUND_ID_CRONET_COMPRESSION,
+                           parse_user_agent);
+}
+
+void grpc_workaround_cronet_compression_filter_shutdown(void) {}
diff --git a/src/core/ext/filters/workarounds/workaround_cronet_compression_filter.h b/src/core/ext/filters/workarounds/workaround_cronet_compression_filter.h
new file mode 100644
index 0000000000..9dae4f0734
--- /dev/null
+++ b/src/core/ext/filters/workarounds/workaround_cronet_compression_filter.h
@@ -0,0 +1,25 @@
+//
+// Copyright 2017 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#ifndef GRPC_CORE_EXT_FILTERS_WORKAROUNDS_WORKAROUND_CRONET_COMPRESSION_FILTER_H
+#define GRPC_CORE_EXT_FILTERS_WORKAROUNDS_WORKAROUND_CRONET_COMPRESSION_FILTER_H
+
+#include "src/core/lib/channel/channel_stack.h"
+
+extern const grpc_channel_filter grpc_workaround_cronet_compression_filter;
+
+#endif /* GRPC_CORE_EXT_FILTERS_WORKAROUNDS_WORKAROUND_CRONET_COMPRESSION_FILTER_H \
+        */
diff --git a/src/core/ext/filters/workarounds/workaround_utils.c b/src/core/ext/filters/workarounds/workaround_utils.c
new file mode 100644
index 0000000000..e600fbee67
--- /dev/null
+++ b/src/core/ext/filters/workarounds/workaround_utils.c
@@ -0,0 +1,51 @@
+//
+// Copyright 2017 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#include "src/core/ext/filters/workarounds/workaround_utils.h"
+
+#include <grpc/support/alloc.h>
+#include <grpc/support/log.h>
+
+user_agent_parser ua_parser[GRPC_MAX_WORKAROUND_ID];
+
+static void destroy_user_agent_md(void *user_agent_md) {
+  gpr_free(user_agent_md);
+}
+
+grpc_workaround_user_agent_md *grpc_parse_user_agent(grpc_mdelem md) {
+  grpc_workaround_user_agent_md *user_agent_md =
+      (grpc_workaround_user_agent_md *)grpc_mdelem_get_user_data(
+          md, destroy_user_agent_md);
+
+  if (NULL != user_agent_md) {
+    return user_agent_md;
+  }
+  user_agent_md = (grpc_workaround_user_agent_md *)gpr_malloc(
+      sizeof(grpc_workaround_user_agent_md));
+  for (int i = 0; i < GRPC_MAX_WORKAROUND_ID; i++) {
+    if (ua_parser[i]) {
+      user_agent_md->workaround_active[i] = ua_parser[i](md);
+    }
+  }
+  grpc_mdelem_set_user_data(md, destroy_user_agent_md, (void *)user_agent_md);
+
+  return user_agent_md;
+}
+
+void grpc_register_workaround(uint32_t id, user_agent_parser parser) {
+  GPR_ASSERT(id < GRPC_MAX_WORKAROUND_ID);
+  ua_parser[id] = parser;
+}
diff --git a/src/core/ext/filters/workarounds/workaround_utils.h b/src/core/ext/filters/workarounds/workaround_utils.h
new file mode 100644
index 0000000000..2ad7a876d5
--- /dev/null
+++ b/src/core/ext/filters/workarounds/workaround_utils.h
@@ -0,0 +1,37 @@
+//
+// Copyright 2017 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#ifndef GRPC_CORE_EXT_FILTERS_WORKAROUNDS_WORKAROUND_UTILS_H
+#define GRPC_CORE_EXT_FILTERS_WORKAROUNDS_WORKAROUND_UTILS_H
+
+#include <grpc/support/workaround_list.h>
+
+#include "src/core/lib/transport/metadata.h"
+
+#define GRPC_WORKAROUND_PRIORITY_HIGH 10001
+#define GRPC_WORKAROUND_PROIRITY_LOW 9999
+
+typedef struct grpc_workaround_user_agent_md {
+  bool workaround_active[GRPC_MAX_WORKAROUND_ID];
+} grpc_workaround_user_agent_md;
+
+grpc_workaround_user_agent_md *grpc_parse_user_agent(grpc_mdelem md);
+
+typedef bool (*user_agent_parser)(grpc_mdelem);
+
+void grpc_register_workaround(uint32_t id, user_agent_parser parser);
+
+#endif /* GRPC_CORE_EXT_FILTERS_WORKAROUNDS_WORKAROUND_UTILS_H */
diff --git a/src/core/ext/transport/chttp2/alpn/alpn.c b/src/core/ext/transport/chttp2/alpn/alpn.c
index 55710dc5ae..ca2e801ec8 100644
--- a/src/core/ext/transport/chttp2/alpn/alpn.c
+++ b/src/core/ext/transport/chttp2/alpn/alpn.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/transport/chttp2/alpn/alpn.h b/src/core/ext/transport/chttp2/alpn/alpn.h
index 1316770f11..379af4b24c 100644
--- a/src/core/ext/transport/chttp2/alpn/alpn.h
+++ b/src/core/ext/transport/chttp2/alpn/alpn.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/transport/chttp2/client/chttp2_connector.c b/src/core/ext/transport/chttp2/client/chttp2_connector.c
index e645eda7e3..983691bbad 100644
--- a/src/core/ext/transport/chttp2/client/chttp2_connector.c
+++ b/src/core/ext/transport/chttp2/client/chttp2_connector.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -139,7 +124,7 @@ static void on_handshake_done(grpc_exec_ctx *exec_ctx, void *arg,
   }
   grpc_closure *notify = c->notify;
   c->notify = NULL;
-  grpc_closure_sched(exec_ctx, notify, error);
+  GRPC_CLOSURE_SCHED(exec_ctx, notify, error);
   grpc_handshake_manager_destroy(exec_ctx, c->handshake_mgr);
   c->handshake_mgr = NULL;
   gpr_mu_unlock(&c->mu);
@@ -171,7 +156,7 @@ static void connected(grpc_exec_ctx *exec_ctx, void *arg, grpc_error *error) {
     memset(c->result, 0, sizeof(*c->result));
     grpc_closure *notify = c->notify;
     c->notify = NULL;
-    grpc_closure_sched(exec_ctx, notify, error);
+    GRPC_CLOSURE_SCHED(exec_ctx, notify, error);
     if (c->endpoint != NULL) {
       grpc_endpoint_shutdown(exec_ctx, c->endpoint, GRPC_ERROR_REF(error));
     }
@@ -199,7 +184,7 @@ static void chttp2_connector_connect(grpc_exec_ctx *exec_ctx,
   c->result = result;
   GPR_ASSERT(c->endpoint == NULL);
   chttp2_connector_ref(con);  // Ref taken for callback.
-  grpc_closure_init(&c->connected, connected, c, grpc_schedule_on_exec_ctx);
+  GRPC_CLOSURE_INIT(&c->connected, connected, c, grpc_schedule_on_exec_ctx);
   GPR_ASSERT(!c->connecting);
   c->connecting = true;
   grpc_tcp_client_connect(exec_ctx, &c->connected, &c->endpoint,
diff --git a/src/core/ext/transport/chttp2/client/chttp2_connector.h b/src/core/ext/transport/chttp2/client/chttp2_connector.h
index d55f6ed669..e258892cfc 100644
--- a/src/core/ext/transport/chttp2/client/chttp2_connector.h
+++ b/src/core/ext/transport/chttp2/client/chttp2_connector.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/transport/chttp2/client/insecure/channel_create.c b/src/core/ext/transport/chttp2/client/insecure/channel_create.c
index ad674b8eb4..cccb347bf1 100644
--- a/src/core/ext/transport/chttp2/client/insecure/channel_create.c
+++ b/src/core/ext/transport/chttp2/client/insecure/channel_create.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -69,11 +54,9 @@ static grpc_channel *client_channel_factory_create_channel(
     return NULL;
   }
   // Add channel arg containing the server URI.
-  grpc_arg arg;
-  arg.type = GRPC_ARG_STRING;
-  arg.key = GRPC_ARG_SERVER_URI;
-  arg.value.string =
-      grpc_resolver_factory_add_default_prefix_if_needed(exec_ctx, target);
+  grpc_arg arg = grpc_channel_arg_string_create(
+      GRPC_ARG_SERVER_URI,
+      grpc_resolver_factory_add_default_prefix_if_needed(exec_ctx, target));
   const char *to_remove[] = {GRPC_ARG_SERVER_URI};
   grpc_channel_args *new_args =
       grpc_channel_args_copy_and_add_and_remove(args, to_remove, 1, &arg, 1);
diff --git a/src/core/ext/transport/chttp2/client/insecure/channel_create_posix.c b/src/core/ext/transport/chttp2/client/insecure/channel_create_posix.c
index f1069e2c57..0346d50b6c 100644
--- a/src/core/ext/transport/chttp2/client/insecure/channel_create_posix.c
+++ b/src/core/ext/transport/chttp2/client/insecure/channel_create_posix.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -56,10 +41,8 @@ grpc_channel *grpc_insecure_channel_create_from_fd(
   GRPC_API_TRACE("grpc_insecure_channel_create(target=%p, fd=%d, args=%p)", 3,
                  (target, fd, args));
 
-  grpc_arg default_authority_arg;
-  default_authority_arg.type = GRPC_ARG_STRING;
-  default_authority_arg.key = GRPC_ARG_DEFAULT_AUTHORITY;
-  default_authority_arg.value.string = "test.authority";
+  grpc_arg default_authority_arg = grpc_channel_arg_string_create(
+      GRPC_ARG_DEFAULT_AUTHORITY, "test.authority");
   grpc_channel_args *final_args =
       grpc_channel_args_copy_and_add(args, &default_authority_arg, 1);
 
diff --git a/src/core/ext/transport/chttp2/client/secure/secure_channel_create.c b/src/core/ext/transport/chttp2/client/secure/secure_channel_create.c
index 119adfade1..d4580f15f5 100644
--- a/src/core/ext/transport/chttp2/client/secure/secure_channel_create.c
+++ b/src/core/ext/transport/chttp2/client/secure/secure_channel_create.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -178,11 +163,9 @@ static grpc_channel *client_channel_factory_create_channel(
     return NULL;
   }
   // Add channel arg containing the server URI.
-  grpc_arg arg;
-  arg.type = GRPC_ARG_STRING;
-  arg.key = GRPC_ARG_SERVER_URI;
-  arg.value.string =
-      grpc_resolver_factory_add_default_prefix_if_needed(exec_ctx, target);
+  grpc_arg arg = grpc_channel_arg_string_create(
+      GRPC_ARG_SERVER_URI,
+      grpc_resolver_factory_add_default_prefix_if_needed(exec_ctx, target));
   const char *to_remove[] = {GRPC_ARG_SERVER_URI};
   grpc_channel_args *new_args =
       grpc_channel_args_copy_and_add_and_remove(args, to_remove, 1, &arg, 1);
diff --git a/src/core/ext/transport/chttp2/server/chttp2_server.c b/src/core/ext/transport/chttp2/server/chttp2_server.c
index a888dc0264..feb95796b3 100644
--- a/src/core/ext/transport/chttp2/server/chttp2_server.c
+++ b/src/core/ext/transport/chttp2/server/chttp2_server.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -127,6 +112,7 @@ static void on_accept(grpc_exec_ctx *exec_ctx, void *arg, grpc_endpoint *tcp,
   gpr_mu_lock(&state->mu);
   if (state->shutdown) {
     gpr_mu_unlock(&state->mu);
+    grpc_endpoint_shutdown(exec_ctx, tcp, GRPC_ERROR_NONE);
     grpc_endpoint_destroy(exec_ctx, tcp);
     gpr_free(acceptor);
     return;
@@ -223,7 +209,7 @@ grpc_error *grpc_chttp2_server_add_port(grpc_exec_ctx *exec_ctx,
     goto error;
   }
   state = gpr_zalloc(sizeof(*state));
-  grpc_closure_init(&state->tcp_server_shutdown_complete,
+  GRPC_CLOSURE_INIT(&state->tcp_server_shutdown_complete,
                     tcp_server_shutdown_complete, state,
                     grpc_schedule_on_exec_ctx);
   err = grpc_tcp_server_create(exec_ctx, &state->tcp_server_shutdown_complete,
diff --git a/src/core/ext/transport/chttp2/server/chttp2_server.h b/src/core/ext/transport/chttp2/server/chttp2_server.h
index 2581ebaae9..ed968496f9 100644
--- a/src/core/ext/transport/chttp2/server/chttp2_server.h
+++ b/src/core/ext/transport/chttp2/server/chttp2_server.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/transport/chttp2/server/insecure/server_chttp2.c b/src/core/ext/transport/chttp2/server/insecure/server_chttp2.c
index c219a7d85f..d42b2d123e 100644
--- a/src/core/ext/transport/chttp2/server/insecure/server_chttp2.c
+++ b/src/core/ext/transport/chttp2/server/insecure/server_chttp2.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/transport/chttp2/server/insecure/server_chttp2_posix.c b/src/core/ext/transport/chttp2/server/insecure/server_chttp2_posix.c
index 6ab176e8ad..e647067f73 100644
--- a/src/core/ext/transport/chttp2/server/insecure/server_chttp2_posix.c
+++ b/src/core/ext/transport/chttp2/server/insecure/server_chttp2_posix.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/transport/chttp2/server/secure/server_secure_chttp2.c b/src/core/ext/transport/chttp2/server/secure/server_secure_chttp2.c
index 88c813f3be..5ad63aaf1f 100644
--- a/src/core/ext/transport/chttp2/server/secure/server_secure_chttp2.c
+++ b/src/core/ext/transport/chttp2/server/secure/server_secure_chttp2.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/transport/chttp2/transport/bin_decoder.c b/src/core/ext/transport/chttp2/transport/bin_decoder.c
index 21bed18c9a..fe7b7e4a42 100644
--- a/src/core/ext/transport/chttp2/transport/bin_decoder.c
+++ b/src/core/ext/transport/chttp2/transport/bin_decoder.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/transport/chttp2/transport/bin_decoder.h b/src/core/ext/transport/chttp2/transport/bin_decoder.h
index 48ffb2ae3b..047b33d587 100644
--- a/src/core/ext/transport/chttp2/transport/bin_decoder.h
+++ b/src/core/ext/transport/chttp2/transport/bin_decoder.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/transport/chttp2/transport/bin_encoder.c b/src/core/ext/transport/chttp2/transport/bin_encoder.c
index 3b8ab1f17a..42d481b3c0 100644
--- a/src/core/ext/transport/chttp2/transport/bin_encoder.c
+++ b/src/core/ext/transport/chttp2/transport/bin_encoder.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/transport/chttp2/transport/bin_encoder.h b/src/core/ext/transport/chttp2/transport/bin_encoder.h
index 0f899c8e34..a8f36a345a 100644
--- a/src/core/ext/transport/chttp2/transport/bin_encoder.h
+++ b/src/core/ext/transport/chttp2/transport/bin_encoder.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/transport/chttp2/transport/chttp2_plugin.c b/src/core/ext/transport/chttp2/transport/chttp2_plugin.c
index 59b21e3330..78551df9c3 100644
--- a/src/core/ext/transport/chttp2/transport/chttp2_plugin.c
+++ b/src/core/ext/transport/chttp2/transport/chttp2_plugin.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -36,8 +21,11 @@
 #include "src/core/lib/transport/metadata.h"
 
 void grpc_chttp2_plugin_init(void) {
-  grpc_register_tracer("http", &grpc_http_trace);
-  grpc_register_tracer("flowctl", &grpc_flowctl_trace);
+  grpc_register_tracer(&grpc_http_trace);
+  grpc_register_tracer(&grpc_flowctl_trace);
+#ifndef NDEBUG
+  grpc_register_tracer(&grpc_trace_chttp2_refcount);
+#endif
 }
 
 void grpc_chttp2_plugin_shutdown(void) {}
diff --git a/src/core/ext/transport/chttp2/transport/chttp2_transport.c b/src/core/ext/transport/chttp2/transport/chttp2_transport.c
index eaf880708f..ffcd715cf6 100644
--- a/src/core/ext/transport/chttp2/transport/chttp2_transport.c
+++ b/src/core/ext/transport/chttp2/transport/chttp2_transport.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -48,9 +33,10 @@
 #include "src/core/ext/transport/chttp2/transport/internal.h"
 #include "src/core/ext/transport/chttp2/transport/varint.h"
 #include "src/core/lib/channel/channel_args.h"
+#include "src/core/lib/compression/stream_compression.h"
 #include "src/core/lib/http/parser.h"
+#include "src/core/lib/iomgr/executor.h"
 #include "src/core/lib/iomgr/timer.h"
-#include "src/core/lib/iomgr/workqueue.h"
 #include "src/core/lib/profiling/timers.h"
 #include "src/core/lib/slice/slice_internal.h"
 #include "src/core/lib/slice/slice_string_helpers.h"
@@ -68,7 +54,7 @@
 #define DEFAULT_CONNECTION_WINDOW_TARGET (1024 * 1024)
 #define MAX_WINDOW 0x7fffffffu
 #define MAX_WRITE_BUFFER_SIZE (64 * 1024 * 1024)
-#define DEFAULT_MAX_HEADER_LIST_SIZE (16 * 1024)
+#define DEFAULT_MAX_HEADER_LIST_SIZE (8 * 1024)
 
 #define DEFAULT_CLIENT_KEEPALIVE_TIME_MS INT_MAX
 #define DEFAULT_CLIENT_KEEPALIVE_TIMEOUT_MS 20000 /* 20 seconds */
@@ -89,8 +75,13 @@ static bool g_default_keepalive_permit_without_calls =
     DEFAULT_KEEPALIVE_PERMIT_WITHOUT_CALLS;
 
 #define MAX_CLIENT_STREAM_ID 0x7fffffffu
-grpc_tracer_flag grpc_http_trace = GRPC_TRACER_INITIALIZER(false);
-grpc_tracer_flag grpc_flowctl_trace = GRPC_TRACER_INITIALIZER(false);
+grpc_tracer_flag grpc_http_trace = GRPC_TRACER_INITIALIZER(false, "http");
+grpc_tracer_flag grpc_flowctl_trace = GRPC_TRACER_INITIALIZER(false, "flowctl");
+
+#ifndef NDEBUG
+grpc_tracer_flag grpc_trace_chttp2_refcount =
+    GRPC_TRACER_INITIALIZER(false, "chttp2_refcount");
+#endif
 
 static const grpc_transport_vtable vtable;
 
@@ -107,8 +98,9 @@ static void read_action_locked(grpc_exec_ctx *exec_ctx, void *t,
 static void complete_fetch_locked(grpc_exec_ctx *exec_ctx, void *gs,
                                   grpc_error *error);
 /** Set a transport level setting, and push it to our peer */
-static void push_setting(grpc_exec_ctx *exec_ctx, grpc_chttp2_transport *t,
-                         grpc_chttp2_setting_id id, uint32_t value);
+static void queue_setting_update(grpc_exec_ctx *exec_ctx,
+                                 grpc_chttp2_transport *t,
+                                 grpc_chttp2_setting_id id, uint32_t value);
 
 static void close_from_api(grpc_exec_ctx *exec_ctx, grpc_chttp2_transport *t,
                            grpc_chttp2_stream *s, grpc_error *error);
@@ -228,20 +220,26 @@ static void destruct_transport(grpc_exec_ctx *exec_ctx,
   gpr_free(t);
 }
 
-#ifdef GRPC_CHTTP2_REFCOUNTING_DEBUG
+#ifndef NDEBUG
 void grpc_chttp2_unref_transport(grpc_exec_ctx *exec_ctx,
                                  grpc_chttp2_transport *t, const char *reason,
                                  const char *file, int line) {
-  gpr_log(GPR_DEBUG, "chttp2:unref:%p %" PRIdPTR "->%" PRIdPTR " %s [%s:%d]", t,
-          t->refs.count, t->refs.count - 1, reason, file, line);
+  if (GRPC_TRACER_ON(grpc_trace_chttp2_refcount)) {
+    gpr_atm val = gpr_atm_no_barrier_load(&t->refs.count);
+    gpr_log(GPR_DEBUG, "chttp2:unref:%p %" PRIdPTR "->%" PRIdPTR " %s [%s:%d]",
+            t, val, val - 1, reason, file, line);
+  }
   if (!gpr_unref(&t->refs)) return;
   destruct_transport(exec_ctx, t);
 }
 
 void grpc_chttp2_ref_transport(grpc_chttp2_transport *t, const char *reason,
                                const char *file, int line) {
-  gpr_log(GPR_DEBUG, "chttp2:  ref:%p %" PRIdPTR "->%" PRIdPTR " %s [%s:%d]", t,
-          t->refs.count, t->refs.count + 1, reason, file, line);
+  if (GRPC_TRACER_ON(grpc_trace_chttp2_refcount)) {
+    gpr_atm val = gpr_atm_no_barrier_load(&t->refs.count);
+    gpr_log(GPR_DEBUG, "chttp2:  ref:%p %" PRIdPTR "->%" PRIdPTR " %s [%s:%d]",
+            t, val, val + 1, reason, file, line);
+  }
   gpr_ref(&t->refs);
 }
 #else
@@ -267,7 +265,7 @@ static void init_transport(grpc_exec_ctx *exec_ctx, grpc_chttp2_transport *t,
   t->ep = ep;
   /* one ref is for destroy */
   gpr_ref_init(&t->refs, 1);
-  t->combiner = grpc_combiner_create(grpc_endpoint_get_workqueue(ep));
+  t->combiner = grpc_combiner_create();
   t->peer_string = grpc_endpoint_get_peer(ep);
   t->endpoint_reading = 1;
   t->next_stream_id = is_client ? 1 : 2;
@@ -285,32 +283,30 @@ static void init_transport(grpc_exec_ctx *exec_ctx, grpc_chttp2_transport *t,
   grpc_slice_buffer_init(&t->outbuf);
   grpc_chttp2_hpack_compressor_init(&t->hpack_compressor);
 
-  grpc_closure_init(&t->write_action, write_action, t,
-                    grpc_schedule_on_exec_ctx);
-  grpc_closure_init(&t->read_action_locked, read_action_locked, t,
-                    grpc_combiner_scheduler(t->combiner, false));
-  grpc_closure_init(&t->benign_reclaimer_locked, benign_reclaimer_locked, t,
-                    grpc_combiner_scheduler(t->combiner, false));
-  grpc_closure_init(&t->destructive_reclaimer_locked,
+  GRPC_CLOSURE_INIT(&t->read_action_locked, read_action_locked, t,
+                    grpc_combiner_scheduler(t->combiner));
+  GRPC_CLOSURE_INIT(&t->benign_reclaimer_locked, benign_reclaimer_locked, t,
+                    grpc_combiner_scheduler(t->combiner));
+  GRPC_CLOSURE_INIT(&t->destructive_reclaimer_locked,
                     destructive_reclaimer_locked, t,
-                    grpc_combiner_scheduler(t->combiner, false));
-  grpc_closure_init(&t->retry_initiate_ping_locked, retry_initiate_ping_locked,
-                    t, grpc_combiner_scheduler(t->combiner, false));
-  grpc_closure_init(&t->start_bdp_ping_locked, start_bdp_ping_locked, t,
-                    grpc_combiner_scheduler(t->combiner, false));
-  grpc_closure_init(&t->finish_bdp_ping_locked, finish_bdp_ping_locked, t,
-                    grpc_combiner_scheduler(t->combiner, false));
-  grpc_closure_init(&t->init_keepalive_ping_locked, init_keepalive_ping_locked,
-                    t, grpc_combiner_scheduler(t->combiner, false));
-  grpc_closure_init(&t->start_keepalive_ping_locked,
+                    grpc_combiner_scheduler(t->combiner));
+  GRPC_CLOSURE_INIT(&t->retry_initiate_ping_locked, retry_initiate_ping_locked,
+                    t, grpc_combiner_scheduler(t->combiner));
+  GRPC_CLOSURE_INIT(&t->start_bdp_ping_locked, start_bdp_ping_locked, t,
+                    grpc_combiner_scheduler(t->combiner));
+  GRPC_CLOSURE_INIT(&t->finish_bdp_ping_locked, finish_bdp_ping_locked, t,
+                    grpc_combiner_scheduler(t->combiner));
+  GRPC_CLOSURE_INIT(&t->init_keepalive_ping_locked, init_keepalive_ping_locked,
+                    t, grpc_combiner_scheduler(t->combiner));
+  GRPC_CLOSURE_INIT(&t->start_keepalive_ping_locked,
                     start_keepalive_ping_locked, t,
-                    grpc_combiner_scheduler(t->combiner, false));
-  grpc_closure_init(&t->finish_keepalive_ping_locked,
+                    grpc_combiner_scheduler(t->combiner));
+  GRPC_CLOSURE_INIT(&t->finish_keepalive_ping_locked,
                     finish_keepalive_ping_locked, t,
-                    grpc_combiner_scheduler(t->combiner, false));
-  grpc_closure_init(&t->keepalive_watchdog_fired_locked,
+                    grpc_combiner_scheduler(t->combiner));
+  GRPC_CLOSURE_INIT(&t->keepalive_watchdog_fired_locked,
                     keepalive_watchdog_fired_locked, t,
-                    grpc_combiner_scheduler(t->combiner, false));
+                    grpc_combiner_scheduler(t->combiner));
 
   grpc_bdp_estimator_init(&t->bdp_estimator, t->peer_string);
   t->last_pid_update = gpr_now(GPR_CLOCK_MONOTONIC);
@@ -353,20 +349,21 @@ static void init_transport(grpc_exec_ctx *exec_ctx, grpc_chttp2_transport *t,
   if (is_client) {
     grpc_slice_buffer_add(&t->outbuf, grpc_slice_from_copied_string(
                                           GRPC_CHTTP2_CLIENT_CONNECT_STRING));
-    grpc_chttp2_initiate_write(exec_ctx, t, false, "initial_write");
+    grpc_chttp2_initiate_write(exec_ctx, t, "initial_write");
   }
 
   /* configure http2 the way we like it */
   if (is_client) {
-    push_setting(exec_ctx, t, GRPC_CHTTP2_SETTINGS_ENABLE_PUSH, 0);
-    push_setting(exec_ctx, t, GRPC_CHTTP2_SETTINGS_MAX_CONCURRENT_STREAMS, 0);
+    queue_setting_update(exec_ctx, t, GRPC_CHTTP2_SETTINGS_ENABLE_PUSH, 0);
+    queue_setting_update(exec_ctx, t,
+                         GRPC_CHTTP2_SETTINGS_MAX_CONCURRENT_STREAMS, 0);
   }
-  push_setting(exec_ctx, t, GRPC_CHTTP2_SETTINGS_INITIAL_WINDOW_SIZE,
-               DEFAULT_WINDOW);
-  push_setting(exec_ctx, t, GRPC_CHTTP2_SETTINGS_MAX_HEADER_LIST_SIZE,
-               DEFAULT_MAX_HEADER_LIST_SIZE);
-  push_setting(exec_ctx, t,
-               GRPC_CHTTP2_SETTINGS_GRPC_ALLOW_TRUE_BINARY_METADATA, 1);
+  queue_setting_update(exec_ctx, t, GRPC_CHTTP2_SETTINGS_INITIAL_WINDOW_SIZE,
+                       DEFAULT_WINDOW);
+  queue_setting_update(exec_ctx, t, GRPC_CHTTP2_SETTINGS_MAX_HEADER_LIST_SIZE,
+                       DEFAULT_MAX_HEADER_LIST_SIZE);
+  queue_setting_update(exec_ctx, t,
+                       GRPC_CHTTP2_SETTINGS_GRPC_ALLOW_TRUE_BINARY_METADATA, 1);
 
   t->ping_policy = (grpc_chttp2_repeated_ping_policy){
       .max_pings_without_data = DEFAULT_MAX_PINGS_BETWEEN_DATA,
@@ -394,6 +391,8 @@ static void init_transport(grpc_exec_ctx *exec_ctx, grpc_chttp2_transport *t,
   }
   t->keepalive_permit_without_calls = g_default_keepalive_permit_without_calls;
 
+  t->opt_target = GRPC_CHTTP2_OPTIMIZE_FOR_LATENCY;
+
   if (channel_args) {
     for (i = 0; i < channel_args->num_args; i++) {
       if (0 == strcmp(channel_args->args[i].key,
@@ -476,6 +475,23 @@ static void init_transport(grpc_exec_ctx *exec_ctx, grpc_chttp2_transport *t,
         t->keepalive_permit_without_calls =
             (uint32_t)grpc_channel_arg_get_integer(
                 &channel_args->args[i], (grpc_integer_options){0, 0, 1});
+      } else if (0 == strcmp(channel_args->args[i].key,
+                             GRPC_ARG_OPTIMIZATION_TARGET)) {
+        if (channel_args->args[i].type != GRPC_ARG_STRING) {
+          gpr_log(GPR_ERROR, "%s should be a string",
+                  GRPC_ARG_OPTIMIZATION_TARGET);
+        } else if (0 == strcmp(channel_args->args[i].value.string, "blend")) {
+          t->opt_target = GRPC_CHTTP2_OPTIMIZE_FOR_LATENCY;
+        } else if (0 == strcmp(channel_args->args[i].value.string, "latency")) {
+          t->opt_target = GRPC_CHTTP2_OPTIMIZE_FOR_LATENCY;
+        } else if (0 ==
+                   strcmp(channel_args->args[i].value.string, "throughput")) {
+          t->opt_target = GRPC_CHTTP2_OPTIMIZE_FOR_THROUGHPUT;
+        } else {
+          gpr_log(GPR_ERROR, "%s value '%s' unknown, assuming 'blend'",
+                  GRPC_ARG_OPTIMIZATION_TARGET,
+                  channel_args->args[i].value.string);
+        }
       } else {
         static const struct {
           const char *channel_arg_name;
@@ -518,8 +534,8 @@ static void init_transport(grpc_exec_ctx *exec_ctx, grpc_chttp2_transport *t,
               int value = grpc_channel_arg_get_integer(
                   &channel_args->args[i], settings_map[j].integer_options);
               if (value >= 0) {
-                push_setting(exec_ctx, t, settings_map[j].setting_id,
-                             (uint32_t)value);
+                queue_setting_update(exec_ctx, t, settings_map[j].setting_id,
+                                     (uint32_t)value);
               }
             }
             break;
@@ -529,6 +545,11 @@ static void init_transport(grpc_exec_ctx *exec_ctx, grpc_chttp2_transport *t,
     }
   }
 
+  GRPC_CLOSURE_INIT(&t->write_action, write_action, t,
+                    t->opt_target == GRPC_CHTTP2_OPTIMIZE_FOR_THROUGHPUT
+                        ? grpc_executor_scheduler
+                        : grpc_schedule_on_exec_ctx);
+
   t->ping_state.pings_before_data_required =
       t->ping_policy.max_pings_without_data;
   t->ping_state.is_delayed_ping_timer_set = false;
@@ -549,7 +570,7 @@ static void init_transport(grpc_exec_ctx *exec_ctx, grpc_chttp2_transport *t,
     t->keepalive_state = GRPC_CHTTP2_KEEPALIVE_STATE_DISABLED;
   }
 
-  grpc_chttp2_initiate_write(exec_ctx, t, false, "init");
+  grpc_chttp2_initiate_write(exec_ctx, t, "init");
   post_benign_reclaimer(exec_ctx, t);
 }
 
@@ -567,9 +588,9 @@ static void destroy_transport_locked(grpc_exec_ctx *exec_ctx, void *tp,
 
 static void destroy_transport(grpc_exec_ctx *exec_ctx, grpc_transport *gt) {
   grpc_chttp2_transport *t = (grpc_chttp2_transport *)gt;
-  grpc_closure_sched(exec_ctx, grpc_closure_create(
-                                   destroy_transport_locked, t,
-                                   grpc_combiner_scheduler(t->combiner, false)),
+  GRPC_CLOSURE_SCHED(exec_ctx,
+                     GRPC_CLOSURE_CREATE(destroy_transport_locked, t,
+                                         grpc_combiner_scheduler(t->combiner)),
                      GRPC_ERROR_NONE);
 }
 
@@ -620,7 +641,7 @@ static void close_transport_locked(grpc_exec_ctx *exec_ctx,
   GRPC_ERROR_UNREF(error);
 }
 
-#ifdef GRPC_STREAM_REFCOUNT_DEBUG
+#ifndef NDEBUG
 void grpc_chttp2_stream_ref(grpc_chttp2_stream *s, const char *reason) {
   grpc_stream_ref(s->refcount, reason);
 }
@@ -656,13 +677,13 @@ static int init_stream(grpc_exec_ctx *exec_ctx, grpc_transport *gt,
   grpc_chttp2_data_parser_init(&s->data_parser);
   grpc_slice_buffer_init(&s->flow_controlled_buffer);
   s->deadline = gpr_inf_future(GPR_CLOCK_MONOTONIC);
-  grpc_closure_init(&s->complete_fetch_locked, complete_fetch_locked, s,
+  GRPC_CLOSURE_INIT(&s->complete_fetch_locked, complete_fetch_locked, s,
                     grpc_schedule_on_exec_ctx);
   grpc_slice_buffer_init(&s->unprocessed_incoming_frames_buffer);
   grpc_slice_buffer_init(&s->frame_storage);
   s->pending_byte_stream = false;
-  grpc_closure_init(&s->reset_byte_stream, reset_byte_stream, s,
-                    grpc_combiner_scheduler(t->combiner, false));
+  GRPC_CLOSURE_INIT(&s->reset_byte_stream, reset_byte_stream, s,
+                    grpc_combiner_scheduler(t->combiner));
 
   GRPC_CHTTP2_REF_TRANSPORT(t, "stream");
 
@@ -733,7 +754,7 @@ static void destroy_stream_locked(grpc_exec_ctx *exec_ctx, void *sp,
 
   GPR_TIMER_END("destroy_stream", 0);
 
-  grpc_closure_sched(exec_ctx, s->destroy_stream_arg, GRPC_ERROR_NONE);
+  GRPC_CLOSURE_SCHED(exec_ctx, s->destroy_stream_arg, GRPC_ERROR_NONE);
 }
 
 static void destroy_stream(grpc_exec_ctx *exec_ctx, grpc_transport *gt,
@@ -744,9 +765,9 @@ static void destroy_stream(grpc_exec_ctx *exec_ctx, grpc_transport *gt,
   grpc_chttp2_stream *s = (grpc_chttp2_stream *)gs;
 
   s->destroy_stream_arg = then_schedule_closure;
-  grpc_closure_sched(
-      exec_ctx, grpc_closure_init(&s->destroy_stream, destroy_stream_locked, s,
-                                  grpc_combiner_scheduler(t->combiner, false)),
+  GRPC_CLOSURE_SCHED(
+      exec_ctx, GRPC_CLOSURE_INIT(&s->destroy_stream, destroy_stream_locked, s,
+                                  grpc_combiner_scheduler(t->combiner)),
       GRPC_ERROR_NONE);
   GPR_TIMER_END("destroy_stream", 0);
 }
@@ -784,8 +805,6 @@ static const char *write_state_name(grpc_chttp2_write_state st) {
       return "WRITING";
     case GRPC_CHTTP2_WRITE_STATE_WRITING_WITH_MORE:
       return "WRITING+MORE";
-    case GRPC_CHTTP2_WRITE_STATE_WRITING_WITH_MORE_AND_COVERED_BY_POLLER:
-      return "WRITING+MORE+COVERED";
   }
   GPR_UNREACHABLE_CODE(return "UNKNOWN");
 }
@@ -798,7 +817,7 @@ static void set_write_state(grpc_exec_ctx *exec_ctx, grpc_chttp2_transport *t,
                                  write_state_name(st), reason));
   t->write_state = st;
   if (st == GRPC_CHTTP2_WRITE_STATE_IDLE) {
-    grpc_closure_list_sched(exec_ctx, &t->run_after_write);
+    GRPC_CLOSURE_LIST_SCHED(exec_ctx, &t->run_after_write);
     if (t->close_transport_on_writes_finished != NULL) {
       grpc_error *err = t->close_transport_on_writes_finished;
       t->close_transport_on_writes_finished = NULL;
@@ -808,38 +827,25 @@ static void set_write_state(grpc_exec_ctx *exec_ctx, grpc_chttp2_transport *t,
 }
 
 void grpc_chttp2_initiate_write(grpc_exec_ctx *exec_ctx,
-                                grpc_chttp2_transport *t,
-                                bool covered_by_poller, const char *reason) {
+                                grpc_chttp2_transport *t, const char *reason) {
   GPR_TIMER_BEGIN("grpc_chttp2_initiate_write", 0);
 
   switch (t->write_state) {
     case GRPC_CHTTP2_WRITE_STATE_IDLE:
       set_write_state(exec_ctx, t, GRPC_CHTTP2_WRITE_STATE_WRITING, reason);
       GRPC_CHTTP2_REF_TRANSPORT(t, "writing");
-      grpc_closure_sched(
+      GRPC_CLOSURE_SCHED(
           exec_ctx,
-          grpc_closure_init(
-              &t->write_action_begin_locked, write_action_begin_locked, t,
-              grpc_combiner_finally_scheduler(t->combiner, covered_by_poller)),
+          GRPC_CLOSURE_INIT(&t->write_action_begin_locked,
+                            write_action_begin_locked, t,
+                            grpc_combiner_finally_scheduler(t->combiner)),
           GRPC_ERROR_NONE);
       break;
     case GRPC_CHTTP2_WRITE_STATE_WRITING:
-      set_write_state(
-          exec_ctx, t,
-          covered_by_poller
-              ? GRPC_CHTTP2_WRITE_STATE_WRITING_WITH_MORE_AND_COVERED_BY_POLLER
-              : GRPC_CHTTP2_WRITE_STATE_WRITING_WITH_MORE,
-          reason);
+      set_write_state(exec_ctx, t, GRPC_CHTTP2_WRITE_STATE_WRITING_WITH_MORE,
+                      reason);
       break;
     case GRPC_CHTTP2_WRITE_STATE_WRITING_WITH_MORE:
-      if (covered_by_poller) {
-        set_write_state(
-            exec_ctx, t,
-            GRPC_CHTTP2_WRITE_STATE_WRITING_WITH_MORE_AND_COVERED_BY_POLLER,
-            reason);
-      }
-      break;
-    case GRPC_CHTTP2_WRITE_STATE_WRITING_WITH_MORE_AND_COVERED_BY_POLLER:
       break;
   }
   GPR_TIMER_END("grpc_chttp2_initiate_write", 0);
@@ -855,10 +861,10 @@ void grpc_chttp2_become_writable(
     case GRPC_CHTTP2_STREAM_WRITE_PIGGYBACK:
       break;
     case GRPC_CHTTP2_STREAM_WRITE_INITIATE_COVERED:
-      grpc_chttp2_initiate_write(exec_ctx, t, true, reason);
+      grpc_chttp2_initiate_write(exec_ctx, t, reason);
       break;
     case GRPC_CHTTP2_STREAM_WRITE_INITIATE_UNCOVERED:
-      grpc_chttp2_initiate_write(exec_ctx, t, false, reason);
+      grpc_chttp2_initiate_write(exec_ctx, t, reason);
       break;
   }
 }
@@ -878,12 +884,12 @@ static void write_action_begin_locked(grpc_exec_ctx *exec_ctx, void *gt,
     case GRPC_CHTTP2_PARTIAL_WRITE:
       set_write_state(exec_ctx, t, GRPC_CHTTP2_WRITE_STATE_WRITING_WITH_MORE,
                       "begin writing partial");
-      grpc_closure_sched(exec_ctx, &t->write_action, GRPC_ERROR_NONE);
+      GRPC_CLOSURE_SCHED(exec_ctx, &t->write_action, GRPC_ERROR_NONE);
       break;
     case GRPC_CHTTP2_FULL_WRITE:
       set_write_state(exec_ctx, t, GRPC_CHTTP2_WRITE_STATE_WRITING,
                       "begin writing");
-      grpc_closure_sched(exec_ctx, &t->write_action, GRPC_ERROR_NONE);
+      GRPC_CLOSURE_SCHED(exec_ctx, &t->write_action, GRPC_ERROR_NONE);
       break;
   }
   GPR_TIMER_END("write_action_begin_locked", 0);
@@ -894,8 +900,8 @@ static void write_action(grpc_exec_ctx *exec_ctx, void *gt, grpc_error *error) {
   GPR_TIMER_BEGIN("write_action", 0);
   grpc_endpoint_write(
       exec_ctx, t->ep, &t->outbuf,
-      grpc_closure_init(&t->write_action_end_locked, write_action_end_locked, t,
-                        grpc_combiner_scheduler(t->combiner, false)));
+      GRPC_CLOSURE_INIT(&t->write_action_end_locked, write_action_end_locked, t,
+                        grpc_combiner_scheduler(t->combiner)));
   GPR_TIMER_END("write_action", 0);
 }
 
@@ -929,23 +935,11 @@ static void write_action_end_locked(grpc_exec_ctx *exec_ctx, void *tp,
       set_write_state(exec_ctx, t, GRPC_CHTTP2_WRITE_STATE_WRITING,
                       "continue writing [!covered]");
       GRPC_CHTTP2_REF_TRANSPORT(t, "writing");
-      grpc_closure_run(
-          exec_ctx,
-          grpc_closure_init(
-              &t->write_action_begin_locked, write_action_begin_locked, t,
-              grpc_combiner_finally_scheduler(t->combiner, false)),
-          GRPC_ERROR_NONE);
-      break;
-    case GRPC_CHTTP2_WRITE_STATE_WRITING_WITH_MORE_AND_COVERED_BY_POLLER:
-      GPR_TIMER_MARK("state=writing_stale_with_poller", 0);
-      set_write_state(exec_ctx, t, GRPC_CHTTP2_WRITE_STATE_WRITING,
-                      "continue writing [covered]");
-      GRPC_CHTTP2_REF_TRANSPORT(t, "writing");
-      grpc_closure_run(
+      GRPC_CLOSURE_RUN(
           exec_ctx,
-          grpc_closure_init(&t->write_action_begin_locked,
+          GRPC_CLOSURE_INIT(&t->write_action_begin_locked,
                             write_action_begin_locked, t,
-                            grpc_combiner_finally_scheduler(t->combiner, true)),
+                            grpc_combiner_finally_scheduler(t->combiner)),
           GRPC_ERROR_NONE);
       break;
   }
@@ -956,8 +950,11 @@ static void write_action_end_locked(grpc_exec_ctx *exec_ctx, void *tp,
   GPR_TIMER_END("terminate_writing_with_lock", 0);
 }
 
-static void push_setting(grpc_exec_ctx *exec_ctx, grpc_chttp2_transport *t,
-                         grpc_chttp2_setting_id id, uint32_t value) {
+// Dirties an HTTP2 setting to be sent out next time a writing path occurs.
+// If the change needs to occur immediately, manually initiate a write.
+static void queue_setting_update(grpc_exec_ctx *exec_ctx,
+                                 grpc_chttp2_transport *t,
+                                 grpc_chttp2_setting_id id, uint32_t value) {
   const grpc_chttp2_setting_parameters *sp =
       &grpc_chttp2_settings_parameters[id];
   uint32_t use_value = GPR_CLAMP(value, sp->min_value, sp->max_value);
@@ -968,7 +965,6 @@ static void push_setting(grpc_exec_ctx *exec_ctx, grpc_chttp2_transport *t,
   if (use_value != t->settings[GRPC_LOCAL_SETTINGS][id]) {
     t->settings[GRPC_LOCAL_SETTINGS][id] = use_value;
     t->dirtied_local_settings = 1;
-    grpc_chttp2_initiate_write(exec_ctx, t, false, "push_setting");
   }
 }
 
@@ -1071,7 +1067,7 @@ static void null_then_run_closure(grpc_exec_ctx *exec_ctx,
                                   grpc_closure **closure, grpc_error *error) {
   grpc_closure *c = *closure;
   *closure = NULL;
-  grpc_closure_run(exec_ctx, c, error);
+  GRPC_CLOSURE_RUN(exec_ctx, c, error);
 }
 
 void grpc_chttp2_complete_closure_step(grpc_exec_ctx *exec_ctx,
@@ -1113,7 +1109,7 @@ void grpc_chttp2_complete_closure_step(grpc_exec_ctx *exec_ctx,
     }
     if ((t->write_state == GRPC_CHTTP2_WRITE_STATE_IDLE) ||
         !(closure->next_data.scratch & CLOSURE_BARRIER_MAY_COVER_WRITE)) {
-      grpc_closure_run(exec_ctx, closure, closure->error_data.error);
+      GRPC_CLOSURE_RUN(exec_ctx, closure, closure->error_data.error);
     } else {
       grpc_closure_list_append(&t->run_after_write, closure,
                                closure->error_data.error);
@@ -1211,7 +1207,7 @@ static void do_nothing(grpc_exec_ctx *exec_ctx, void *arg, grpc_error *error) {}
 
 static void log_metadata(const grpc_metadata_batch *md_batch, uint32_t id,
                          bool is_client, bool is_initial) {
-  for (grpc_linked_mdelem *md = md_batch->list.head; md != md_batch->list.tail;
+  for (grpc_linked_mdelem *md = md_batch->list.head; md != NULL;
        md = md->next) {
     char *key = grpc_slice_to_c_string(GRPC_MDKEY(md->md));
     char *value = grpc_slice_to_c_string(GRPC_MDVALUE(md->md));
@@ -1249,7 +1245,7 @@ static void perform_stream_op_locked(grpc_exec_ctx *exec_ctx, void *stream_op,
   grpc_closure *on_complete = op->on_complete;
   if (on_complete == NULL) {
     on_complete =
-        grpc_closure_create(do_nothing, NULL, grpc_schedule_on_exec_ctx);
+        GRPC_CLOSURE_CREATE(do_nothing, NULL, grpc_schedule_on_exec_ctx);
   }
 
   /* use final_data as a barrier until enqueue time; the inital counter is
@@ -1362,7 +1358,6 @@ static void perform_stream_op_locked(grpc_exec_ctx *exec_ctx, void *stream_op,
       s->next_message_end_offset = s->flow_controlled_bytes_written +
                                    (int64_t)s->flow_controlled_buffer.length +
                                    (int64_t)len;
-      s->complete_fetch_covered_by_poller = op->covered_by_poller;
       if (flags & GRPC_WRITE_BUFFER_HINT) {
         s->next_message_end_offset -= t->write_buffer_size;
         s->write_buffering = true;
@@ -1429,6 +1424,8 @@ static void perform_stream_op_locked(grpc_exec_ctx *exec_ctx, void *stream_op,
         op_payload->recv_initial_metadata.recv_initial_metadata_ready;
     s->recv_initial_metadata =
         op_payload->recv_initial_metadata.recv_initial_metadata;
+    s->trailing_metadata_available =
+        op_payload->recv_initial_metadata.trailing_metadata_available;
     grpc_chttp2_maybe_complete_recv_initial_metadata(exec_ctx, t, s);
   }
 
@@ -1474,6 +1471,21 @@ static void perform_stream_op(grpc_exec_ctx *exec_ctx, grpc_transport *gt,
   grpc_chttp2_transport *t = (grpc_chttp2_transport *)gt;
   grpc_chttp2_stream *s = (grpc_chttp2_stream *)gs;
 
+  if (!t->is_client) {
+    if (op->send_initial_metadata) {
+      gpr_timespec deadline =
+          op->payload->send_initial_metadata.send_initial_metadata->deadline;
+      GPR_ASSERT(0 ==
+                 gpr_time_cmp(gpr_inf_future(deadline.clock_type), deadline));
+    }
+    if (op->send_trailing_metadata) {
+      gpr_timespec deadline =
+          op->payload->send_trailing_metadata.send_trailing_metadata->deadline;
+      GPR_ASSERT(0 ==
+                 gpr_time_cmp(gpr_inf_future(deadline.clock_type), deadline));
+    }
+  }
+
   if (GRPC_TRACER_ON(grpc_http_trace)) {
     char *str = grpc_transport_stream_op_batch_string(op);
     gpr_log(GPR_DEBUG, "perform_stream_op[s=%p]: %s", s, str);
@@ -1482,11 +1494,10 @@ static void perform_stream_op(grpc_exec_ctx *exec_ctx, grpc_transport *gt,
 
   op->handler_private.extra_arg = gs;
   GRPC_CHTTP2_STREAM_REF(s, "perform_stream_op");
-  grpc_closure_sched(
+  GRPC_CLOSURE_SCHED(
       exec_ctx,
-      grpc_closure_init(
-          &op->handler_private.closure, perform_stream_op_locked, op,
-          grpc_combiner_scheduler(t->combiner, op->covered_by_poller)),
+      GRPC_CLOSURE_INIT(&op->handler_private.closure, perform_stream_op_locked,
+                        op, grpc_combiner_scheduler(t->combiner)),
       GRPC_ERROR_NONE);
   GPR_TIMER_END("perform_stream_op", 0);
 }
@@ -1499,7 +1510,7 @@ static void cancel_pings(grpc_exec_ctx *exec_ctx, grpc_chttp2_transport *t,
     grpc_chttp2_ping_queue *pq = &t->ping_queues[i];
     for (size_t j = 0; j < GRPC_CHTTP2_PCL_COUNT; j++) {
       grpc_closure_list_fail_all(&pq->lists[j], GRPC_ERROR_REF(error));
-      grpc_closure_list_sched(exec_ctx, &pq->lists[j]);
+      GRPC_CLOSURE_LIST_SCHED(exec_ctx, &pq->lists[j]);
     }
   }
   GRPC_ERROR_UNREF(error);
@@ -1513,7 +1524,7 @@ static void send_ping_locked(grpc_exec_ctx *exec_ctx, grpc_chttp2_transport *t,
                            GRPC_ERROR_NONE);
   if (grpc_closure_list_append(&pq->lists[GRPC_CHTTP2_PCL_NEXT], on_ack,
                                GRPC_ERROR_NONE)) {
-    grpc_chttp2_initiate_write(exec_ctx, t, false, "send_ping");
+    grpc_chttp2_initiate_write(exec_ctx, t, "send_ping");
   }
 }
 
@@ -1521,7 +1532,7 @@ static void retry_initiate_ping_locked(grpc_exec_ctx *exec_ctx, void *tp,
                                        grpc_error *error) {
   grpc_chttp2_transport *t = tp;
   t->ping_state.is_delayed_ping_timer_set = false;
-  grpc_chttp2_initiate_write(exec_ctx, t, false, "retry_send_ping");
+  grpc_chttp2_initiate_write(exec_ctx, t, "retry_send_ping");
 }
 
 void grpc_chttp2_ack_ping(grpc_exec_ctx *exec_ctx, grpc_chttp2_transport *t,
@@ -1534,9 +1545,9 @@ void grpc_chttp2_ack_ping(grpc_exec_ctx *exec_ctx, grpc_chttp2_transport *t,
     gpr_free(from);
     return;
   }
-  grpc_closure_list_sched(exec_ctx, &pq->lists[GRPC_CHTTP2_PCL_INFLIGHT]);
+  GRPC_CLOSURE_LIST_SCHED(exec_ctx, &pq->lists[GRPC_CHTTP2_PCL_INFLIGHT]);
   if (!grpc_closure_list_empty(pq->lists[GRPC_CHTTP2_PCL_NEXT])) {
-    grpc_chttp2_initiate_write(exec_ctx, t, false, "continue_pings");
+    grpc_chttp2_initiate_write(exec_ctx, t, "continue_pings");
   }
 }
 
@@ -1549,7 +1560,7 @@ static void send_goaway(grpc_exec_ctx *exec_ctx, grpc_chttp2_transport *t,
                         &slice, &http_error);
   grpc_chttp2_goaway_append(t->last_new_stream_id, (uint32_t)http_error,
                             grpc_slice_ref_internal(slice), &t->qbuf);
-  grpc_chttp2_initiate_write(exec_ctx, t, false, "goaway_sent");
+  grpc_chttp2_initiate_write(exec_ctx, t, "goaway_sent");
   GRPC_ERROR_UNREF(error);
 }
 
@@ -1575,12 +1586,6 @@ static void perform_transport_op_locked(grpc_exec_ctx *exec_ctx,
   grpc_chttp2_transport *t = op->handler_private.extra_arg;
   grpc_error *close_transport = op->disconnect_with_error;
 
-  if (op->on_connectivity_state_change != NULL) {
-    grpc_connectivity_state_notify_on_state_change(
-        exec_ctx, &t->channel_callback.state_tracker, op->connectivity_state,
-        op->on_connectivity_state_change);
-  }
-
   if (op->goaway_error) {
     send_goaway(exec_ctx, t, op->goaway_error);
   }
@@ -1604,11 +1609,17 @@ static void perform_transport_op_locked(grpc_exec_ctx *exec_ctx,
                      op->send_ping);
   }
 
+  if (op->on_connectivity_state_change != NULL) {
+    grpc_connectivity_state_notify_on_state_change(
+        exec_ctx, &t->channel_callback.state_tracker, op->connectivity_state,
+        op->on_connectivity_state_change);
+  }
+
   if (close_transport != GRPC_ERROR_NONE) {
     close_transport_locked(exec_ctx, t, close_transport);
   }
 
-  grpc_closure_run(exec_ctx, op->on_consumed, GRPC_ERROR_NONE);
+  GRPC_CLOSURE_RUN(exec_ctx, op->on_consumed, GRPC_ERROR_NONE);
 
   GRPC_CHTTP2_UNREF_TRANSPORT(exec_ctx, t, "transport_op");
 }
@@ -1620,11 +1631,11 @@ static void perform_transport_op(grpc_exec_ctx *exec_ctx, grpc_transport *gt,
   gpr_free(msg);
   op->handler_private.extra_arg = gt;
   GRPC_CHTTP2_REF_TRANSPORT(t, "transport_op");
-  grpc_closure_sched(
-      exec_ctx, grpc_closure_init(&op->handler_private.closure,
-                                  perform_transport_op_locked, op,
-                                  grpc_combiner_scheduler(t->combiner, false)),
-      GRPC_ERROR_NONE);
+  GRPC_CLOSURE_SCHED(exec_ctx,
+                     GRPC_CLOSURE_INIT(&op->handler_private.closure,
+                                       perform_transport_op_locked, op,
+                                       grpc_combiner_scheduler(t->combiner)),
+                     GRPC_ERROR_NONE);
 }
 
 /*******************************************************************************
@@ -1779,7 +1790,7 @@ void grpc_chttp2_cancel_stream(grpc_exec_ctx *exec_ctx,
       grpc_slice_buffer_add(
           &t->qbuf, grpc_chttp2_rst_stream_create(s->id, (uint32_t)http_error,
                                                   &s->stats.outgoing));
-      grpc_chttp2_initiate_write(exec_ctx, t, false, "rst_stream");
+      grpc_chttp2_initiate_write(exec_ctx, t, "rst_stream");
     }
   }
   if (due_to_error != GRPC_ERROR_NONE && !s->seen_error) {
@@ -2092,7 +2103,7 @@ static void close_from_api(grpc_exec_ctx *exec_ctx, grpc_chttp2_transport *t,
                                               &s->stats.outgoing));
 
   grpc_chttp2_mark_stream_closed(exec_ctx, t, s, 1, 1, error);
-  grpc_chttp2_initiate_write(exec_ctx, t, false, "close_from_api");
+  grpc_chttp2_initiate_write(exec_ctx, t, "close_from_api");
 }
 
 typedef struct {
@@ -2121,15 +2132,8 @@ static void end_all_the_calls(grpc_exec_ctx *exec_ctx, grpc_chttp2_transport *t,
 
 static void update_bdp(grpc_exec_ctx *exec_ctx, grpc_chttp2_transport *t,
                        double bdp_dbl) {
-  int32_t bdp;
-  const int32_t kMinBDP = 128;
-  if (bdp_dbl <= kMinBDP) {
-    bdp = kMinBDP;
-  } else if (bdp_dbl > INT32_MAX) {
-    bdp = INT32_MAX;
-  } else {
-    bdp = (int32_t)(bdp_dbl);
-  }
+  // initial window size bounded [1,2^31-1], but we set the min to 128.
+  int32_t bdp = GPR_CLAMP((int32_t)bdp_dbl, 128, INT32_MAX);
   int64_t delta =
       (int64_t)bdp -
       (int64_t)t->settings[GRPC_LOCAL_SETTINGS]
@@ -2141,9 +2145,28 @@ static void update_bdp(grpc_exec_ctx *exec_ctx, grpc_chttp2_transport *t,
     gpr_log(GPR_DEBUG, "%s: update initial window size to %d", t->peer_string,
             (int)bdp);
   }
-  push_setting(exec_ctx, t, GRPC_CHTTP2_SETTINGS_INITIAL_WINDOW_SIZE,
-               (uint32_t)bdp);
-  push_setting(exec_ctx, t, GRPC_CHTTP2_SETTINGS_MAX_FRAME_SIZE, (uint32_t)bdp);
+  queue_setting_update(exec_ctx, t, GRPC_CHTTP2_SETTINGS_INITIAL_WINDOW_SIZE,
+                       (uint32_t)bdp);
+}
+
+static void update_frame(grpc_exec_ctx *exec_ctx, grpc_chttp2_transport *t,
+                         double bw_dbl, double bdp_dbl) {
+  int32_t bdp = (int32_t)GPR_CLAMP(bdp_dbl, 128.0, INT32_MAX);
+  int32_t target = (int32_t)GPR_MAX(bw_dbl / 1000, bdp);
+  // frame size is bounded [2^14,2^24-1]
+  int32_t frame_size = GPR_CLAMP(target, 16384, 16777215);
+  int64_t delta = (int64_t)frame_size -
+                  (int64_t)t->settings[GRPC_LOCAL_SETTINGS]
+                                      [GRPC_CHTTP2_SETTINGS_MAX_FRAME_SIZE];
+  if (delta == 0 || (delta > -frame_size / 10 && delta < frame_size / 10)) {
+    return;
+  }
+  if (GRPC_TRACER_ON(grpc_bdp_estimator_trace)) {
+    gpr_log(GPR_DEBUG, "%s: update max_frame size to %d", t->peer_string,
+            (int)frame_size);
+  }
+  queue_setting_update(exec_ctx, t, GRPC_CHTTP2_SETTINGS_MAX_FRAME_SIZE,
+                       (uint32_t)frame_size);
 }
 
 static grpc_error *try_http_parsing(grpc_exec_ctx *exec_ctx,
@@ -2262,6 +2285,7 @@ static void read_action_locked(grpc_exec_ctx *exec_ctx, void *tp,
       }
 
       int64_t estimate = -1;
+      double bdp_guess = -1;
       if (grpc_bdp_estimator_get_estimate(&t->bdp_estimator, &estimate)) {
         double target = 1 + log2((double)estimate);
         double memory_pressure = grpc_resource_quota_get_memory_pressure(
@@ -2279,9 +2303,15 @@ static void read_action_locked(grpc_exec_ctx *exec_ctx, void *tp,
         }
         double log2_bdp_guess =
             grpc_pid_controller_update(&t->pid_controller, bdp_error, dt);
-        update_bdp(exec_ctx, t, pow(2, log2_bdp_guess));
+        bdp_guess = pow(2, log2_bdp_guess);
+        update_bdp(exec_ctx, t, bdp_guess);
         t->last_pid_update = now;
       }
+
+      double bw = -1;
+      if (grpc_bdp_estimator_get_bw(&t->bdp_estimator, &bw)) {
+        update_frame(exec_ctx, t, bw, bdp_guess);
+      }
     }
     GRPC_CHTTP2_UNREF_TRANSPORT(exec_ctx, t, "keep_reading");
   } else {
@@ -2476,7 +2506,7 @@ static void reset_byte_stream(grpc_exec_ctx *exec_ctx, void *arg,
     grpc_chttp2_maybe_complete_recv_trailing_metadata(exec_ctx, s->t, s);
   } else {
     GPR_ASSERT(error != GRPC_ERROR_NONE);
-    grpc_closure_sched(exec_ctx, s->on_next, GRPC_ERROR_REF(error));
+    GRPC_CLOSURE_SCHED(exec_ctx, s->on_next, GRPC_ERROR_REF(error));
     s->on_next = NULL;
     GRPC_ERROR_UNREF(s->byte_stream_error);
     s->byte_stream_error = GRPC_ERROR_NONE;
@@ -2555,9 +2585,9 @@ static void incoming_byte_stream_next_locked(grpc_exec_ctx *exec_ctx,
   if (s->frame_storage.length > 0) {
     grpc_slice_buffer_swap(&s->frame_storage,
                            &s->unprocessed_incoming_frames_buffer);
-    grpc_closure_sched(exec_ctx, bs->next_action.on_complete, GRPC_ERROR_NONE);
+    GRPC_CLOSURE_SCHED(exec_ctx, bs->next_action.on_complete, GRPC_ERROR_NONE);
   } else if (s->byte_stream_error != GRPC_ERROR_NONE) {
-    grpc_closure_sched(exec_ctx, bs->next_action.on_complete,
+    GRPC_CLOSURE_SCHED(exec_ctx, bs->next_action.on_complete,
                        GRPC_ERROR_REF(s->byte_stream_error));
     if (s->data_parser.parsing_frame != NULL) {
       incoming_byte_stream_unref(exec_ctx, s->data_parser.parsing_frame);
@@ -2567,7 +2597,7 @@ static void incoming_byte_stream_next_locked(grpc_exec_ctx *exec_ctx,
     if (bs->remaining_bytes != 0) {
       s->byte_stream_error =
           GRPC_ERROR_CREATE_FROM_STATIC_STRING("Truncated message");
-      grpc_closure_sched(exec_ctx, bs->next_action.on_complete,
+      GRPC_CLOSURE_SCHED(exec_ctx, bs->next_action.on_complete,
                          GRPC_ERROR_REF(s->byte_stream_error));
       if (s->data_parser.parsing_frame != NULL) {
         incoming_byte_stream_unref(exec_ctx, s->data_parser.parsing_frame);
@@ -2598,11 +2628,11 @@ static bool incoming_byte_stream_next(grpc_exec_ctx *exec_ctx,
     gpr_ref(&bs->refs);
     bs->next_action.max_size_hint = max_size_hint;
     bs->next_action.on_complete = on_complete;
-    grpc_closure_sched(
+    GRPC_CLOSURE_SCHED(
         exec_ctx,
-        grpc_closure_init(
-            &bs->next_action.closure, incoming_byte_stream_next_locked, bs,
-            grpc_combiner_scheduler(bs->transport->combiner, false)),
+        GRPC_CLOSURE_INIT(&bs->next_action.closure,
+                          incoming_byte_stream_next_locked, bs,
+                          grpc_combiner_scheduler(bs->transport->combiner)),
         GRPC_ERROR_NONE);
     GPR_TIMER_END("incoming_byte_stream_next", 0);
     return false;
@@ -2627,7 +2657,7 @@ static grpc_error *incoming_byte_stream_pull(grpc_exec_ctx *exec_ctx,
   } else {
     grpc_error *error =
         GRPC_ERROR_CREATE_FROM_STATIC_STRING("Truncated message");
-    grpc_closure_sched(exec_ctx, &s->reset_byte_stream, GRPC_ERROR_REF(error));
+    GRPC_CLOSURE_SCHED(exec_ctx, &s->reset_byte_stream, GRPC_ERROR_REF(error));
     return error;
   }
   GPR_TIMER_END("incoming_byte_stream_pull", 0);
@@ -2656,11 +2686,10 @@ static void incoming_byte_stream_destroy(grpc_exec_ctx *exec_ctx,
   GPR_TIMER_BEGIN("incoming_byte_stream_destroy", 0);
   grpc_chttp2_incoming_byte_stream *bs =
       (grpc_chttp2_incoming_byte_stream *)byte_stream;
-  grpc_closure_sched(
-      exec_ctx,
-      grpc_closure_init(
-          &bs->destroy_action, incoming_byte_stream_destroy_locked, bs,
-          grpc_combiner_scheduler(bs->transport->combiner, false)),
+  GRPC_CLOSURE_SCHED(
+      exec_ctx, GRPC_CLOSURE_INIT(
+                    &bs->destroy_action, incoming_byte_stream_destroy_locked,
+                    bs, grpc_combiner_scheduler(bs->transport->combiner)),
       GRPC_ERROR_NONE);
   GPR_TIMER_END("incoming_byte_stream_destroy", 0);
 }
@@ -2671,7 +2700,7 @@ static void incoming_byte_stream_publish_error(
   grpc_chttp2_stream *s = bs->stream;
 
   GPR_ASSERT(error != GRPC_ERROR_NONE);
-  grpc_closure_sched(exec_ctx, s->on_next, GRPC_ERROR_REF(error));
+  GRPC_CLOSURE_SCHED(exec_ctx, s->on_next, GRPC_ERROR_REF(error));
   s->on_next = NULL;
   GRPC_ERROR_UNREF(s->byte_stream_error);
   s->byte_stream_error = GRPC_ERROR_REF(error);
@@ -2688,7 +2717,7 @@ grpc_error *grpc_chttp2_incoming_byte_stream_push(
     grpc_error *error =
         GRPC_ERROR_CREATE_FROM_STATIC_STRING("Too many bytes in stream");
 
-    grpc_closure_sched(exec_ctx, &s->reset_byte_stream, GRPC_ERROR_REF(error));
+    GRPC_CLOSURE_SCHED(exec_ctx, &s->reset_byte_stream, GRPC_ERROR_REF(error));
     grpc_slice_unref_internal(exec_ctx, slice);
     return error;
   } else {
@@ -2711,7 +2740,7 @@ grpc_error *grpc_chttp2_incoming_byte_stream_finished(
     }
   }
   if (error != GRPC_ERROR_NONE && reset_on_error) {
-    grpc_closure_sched(exec_ctx, &s->reset_byte_stream, GRPC_ERROR_REF(error));
+    GRPC_CLOSURE_SCHED(exec_ctx, &s->reset_byte_stream, GRPC_ERROR_REF(error));
   }
   incoming_byte_stream_unref(exec_ctx, bs);
   return error;
@@ -2731,6 +2760,7 @@ grpc_chttp2_incoming_byte_stream *grpc_chttp2_incoming_byte_stream_create(
   gpr_ref_init(&incoming_byte_stream->refs, 2);
   incoming_byte_stream->transport = t;
   incoming_byte_stream->stream = s;
+  GRPC_ERROR_UNREF(s->byte_stream_error);
   s->byte_stream_error = GRPC_ERROR_NONE;
   return incoming_byte_stream;
 }
@@ -2945,5 +2975,5 @@ void grpc_chttp2_transport_start_reading(grpc_exec_ctx *exec_ctx,
     grpc_slice_buffer_move_into(read_buffer, &t->read_buffer);
     gpr_free(read_buffer);
   }
-  grpc_closure_sched(exec_ctx, &t->read_action_locked, GRPC_ERROR_NONE);
+  GRPC_CLOSURE_SCHED(exec_ctx, &t->read_action_locked, GRPC_ERROR_NONE);
 }
diff --git a/src/core/ext/transport/chttp2/transport/chttp2_transport.h b/src/core/ext/transport/chttp2/transport/chttp2_transport.h
index 83b17d1936..0c4e2a91c0 100644
--- a/src/core/ext/transport/chttp2/transport/chttp2_transport.h
+++ b/src/core/ext/transport/chttp2/transport/chttp2_transport.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -41,6 +26,10 @@
 extern grpc_tracer_flag grpc_http_trace;
 extern grpc_tracer_flag grpc_flowctl_trace;
 
+#ifndef NDEBUG
+extern grpc_tracer_flag grpc_trace_chttp2_refcount;
+#endif
+
 grpc_transport *grpc_create_chttp2_transport(
     grpc_exec_ctx *exec_ctx, const grpc_channel_args *channel_args,
     grpc_endpoint *ep, int is_client);
diff --git a/src/core/ext/transport/chttp2/transport/frame.h b/src/core/ext/transport/chttp2/transport/frame.h
index ffd4d9669b..dba4c004ec 100644
--- a/src/core/ext/transport/chttp2/transport/frame.h
+++ b/src/core/ext/transport/chttp2/transport/frame.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/transport/chttp2/transport/frame_data.c b/src/core/ext/transport/chttp2/transport/frame_data.c
index 8cb8489794..dead6be77f 100644
--- a/src/core/ext/transport/chttp2/transport/frame_data.c
+++ b/src/core/ext/transport/chttp2/transport/frame_data.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -143,6 +128,7 @@ grpc_error *grpc_deframe_unprocessed_incoming_frames(
         grpc_slice_unref_internal(exec_ctx, slice);
         return GRPC_ERROR_REF(p->error);
       case GRPC_CHTTP2_DATA_FH_0:
+        s->stats.incoming.framing_bytes++;
         p->frame_type = *cur;
         switch (p->frame_type) {
           case 0:
@@ -174,6 +160,7 @@ grpc_error *grpc_deframe_unprocessed_incoming_frames(
         }
       /* fallthrough */
       case GRPC_CHTTP2_DATA_FH_1:
+        s->stats.incoming.framing_bytes++;
         p->frame_size = ((uint32_t)*cur) << 24;
         if (++cur == end) {
           p->state = GRPC_CHTTP2_DATA_FH_2;
@@ -182,6 +169,7 @@ grpc_error *grpc_deframe_unprocessed_incoming_frames(
         }
       /* fallthrough */
       case GRPC_CHTTP2_DATA_FH_2:
+        s->stats.incoming.framing_bytes++;
         p->frame_size |= ((uint32_t)*cur) << 16;
         if (++cur == end) {
           p->state = GRPC_CHTTP2_DATA_FH_3;
@@ -190,6 +178,7 @@ grpc_error *grpc_deframe_unprocessed_incoming_frames(
         }
       /* fallthrough */
       case GRPC_CHTTP2_DATA_FH_3:
+        s->stats.incoming.framing_bytes++;
         p->frame_size |= ((uint32_t)*cur) << 8;
         if (++cur == end) {
           p->state = GRPC_CHTTP2_DATA_FH_4;
@@ -198,6 +187,7 @@ grpc_error *grpc_deframe_unprocessed_incoming_frames(
         }
       /* fallthrough */
       case GRPC_CHTTP2_DATA_FH_4:
+        s->stats.incoming.framing_bytes++;
         GPR_ASSERT(stream_out != NULL);
         GPR_ASSERT(p->parsing_frame == NULL);
         p->frame_size |= ((uint32_t)*cur);
@@ -234,6 +224,7 @@ grpc_error *grpc_deframe_unprocessed_incoming_frames(
         }
         uint32_t remaining = (uint32_t)(end - cur);
         if (remaining == p->frame_size) {
+          s->stats.incoming.data_bytes += remaining;
           if (GRPC_ERROR_NONE != (error = grpc_chttp2_incoming_byte_stream_push(
                                       exec_ctx, p->parsing_frame,
                                       grpc_slice_sub(slice, (size_t)(cur - beg),
@@ -253,6 +244,7 @@ grpc_error *grpc_deframe_unprocessed_incoming_frames(
           grpc_slice_unref_internal(exec_ctx, slice);
           return GRPC_ERROR_NONE;
         } else if (remaining < p->frame_size) {
+          s->stats.incoming.data_bytes += remaining;
           if (GRPC_ERROR_NONE != (error = grpc_chttp2_incoming_byte_stream_push(
                                       exec_ctx, p->parsing_frame,
                                       grpc_slice_sub(slice, (size_t)(cur - beg),
@@ -265,6 +257,7 @@ grpc_error *grpc_deframe_unprocessed_incoming_frames(
           return GRPC_ERROR_NONE;
         } else {
           GPR_ASSERT(remaining > p->frame_size);
+          s->stats.incoming.data_bytes += p->frame_size;
           if (GRPC_ERROR_NONE !=
               (grpc_chttp2_incoming_byte_stream_push(
                   exec_ctx, p->parsing_frame,
@@ -301,7 +294,6 @@ grpc_error *grpc_chttp2_data_parser_parse(grpc_exec_ctx *exec_ctx, void *parser,
                                           grpc_chttp2_stream *s,
                                           grpc_slice slice, int is_last) {
   /* grpc_error *error = parse_inner_buffer(exec_ctx, p, t, s, slice); */
-  s->stats.incoming.framing_bytes += GRPC_SLICE_LENGTH(slice);
   if (!s->pending_byte_stream) {
     grpc_slice_ref_internal(slice);
     grpc_slice_buffer_add(&s->frame_storage, slice);
@@ -310,7 +302,7 @@ grpc_error *grpc_chttp2_data_parser_parse(grpc_exec_ctx *exec_ctx, void *parser,
     GPR_ASSERT(s->frame_storage.length == 0);
     grpc_slice_ref_internal(slice);
     grpc_slice_buffer_add(&s->unprocessed_incoming_frames_buffer, slice);
-    grpc_closure_sched(exec_ctx, s->on_next, GRPC_ERROR_NONE);
+    GRPC_CLOSURE_SCHED(exec_ctx, s->on_next, GRPC_ERROR_NONE);
     s->on_next = NULL;
   } else {
     grpc_slice_ref_internal(slice);
diff --git a/src/core/ext/transport/chttp2/transport/frame_data.h b/src/core/ext/transport/chttp2/transport/frame_data.h
index 9ed4ad0f21..3f1c787847 100644
--- a/src/core/ext/transport/chttp2/transport/frame_data.h
+++ b/src/core/ext/transport/chttp2/transport/frame_data.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/transport/chttp2/transport/frame_goaway.c b/src/core/ext/transport/chttp2/transport/frame_goaway.c
index 0f1c8b0772..4bce84f21c 100644
--- a/src/core/ext/transport/chttp2/transport/frame_goaway.c
+++ b/src/core/ext/transport/chttp2/transport/frame_goaway.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/transport/chttp2/transport/frame_goaway.h b/src/core/ext/transport/chttp2/transport/frame_goaway.h
index 21fe819488..abc48f30c6 100644
--- a/src/core/ext/transport/chttp2/transport/frame_goaway.h
+++ b/src/core/ext/transport/chttp2/transport/frame_goaway.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/transport/chttp2/transport/frame_ping.c b/src/core/ext/transport/chttp2/transport/frame_ping.c
index 4133774986..31673e622d 100644
--- a/src/core/ext/transport/chttp2/transport/frame_ping.c
+++ b/src/core/ext/transport/chttp2/transport/frame_ping.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -130,7 +115,7 @@ grpc_error *grpc_chttp2_ping_parser_parse(grpc_exec_ctx *exec_ctx, void *parser,
               t->ping_acks, t->ping_ack_capacity * sizeof(*t->ping_acks));
         }
         t->ping_acks[t->ping_ack_count++] = p->opaque_8bytes;
-        grpc_chttp2_initiate_write(exec_ctx, t, false, "ping response");
+        grpc_chttp2_initiate_write(exec_ctx, t, "ping response");
       }
     }
   }
diff --git a/src/core/ext/transport/chttp2/transport/frame_ping.h b/src/core/ext/transport/chttp2/transport/frame_ping.h
index 01983d2b12..5969ace9bd 100644
--- a/src/core/ext/transport/chttp2/transport/frame_ping.h
+++ b/src/core/ext/transport/chttp2/transport/frame_ping.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/transport/chttp2/transport/frame_rst_stream.c b/src/core/ext/transport/chttp2/transport/frame_rst_stream.c
index e0caa50e92..689dc8935c 100644
--- a/src/core/ext/transport/chttp2/transport/frame_rst_stream.c
+++ b/src/core/ext/transport/chttp2/transport/frame_rst_stream.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -108,7 +93,7 @@ grpc_error *grpc_chttp2_rst_stream_parser_parse(grpc_exec_ctx *exec_ctx,
                       (((uint32_t)p->reason_bytes[2]) << 8) |
                       (((uint32_t)p->reason_bytes[3]));
     grpc_error *error = GRPC_ERROR_NONE;
-    if (reason != GRPC_HTTP2_NO_ERROR || s->header_frames_received < 2) {
+    if (reason != GRPC_HTTP2_NO_ERROR || s->metadata_buffer[1].size == 0) {
       char *message;
       gpr_asprintf(&message, "Received RST_STREAM with error code %d", reason);
       error = grpc_error_set_int(
diff --git a/src/core/ext/transport/chttp2/transport/frame_rst_stream.h b/src/core/ext/transport/chttp2/transport/frame_rst_stream.h
index 779507a617..d088221b52 100644
--- a/src/core/ext/transport/chttp2/transport/frame_rst_stream.h
+++ b/src/core/ext/transport/chttp2/transport/frame_rst_stream.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/transport/chttp2/transport/frame_settings.c b/src/core/ext/transport/chttp2/transport/frame_settings.c
index dbaafb5929..e3e432a94a 100644
--- a/src/core/ext/transport/chttp2/transport/frame_settings.c
+++ b/src/core/ext/transport/chttp2/transport/frame_settings.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/transport/chttp2/transport/frame_settings.h b/src/core/ext/transport/chttp2/transport/frame_settings.h
index 2a85d0dba7..47479d675d 100644
--- a/src/core/ext/transport/chttp2/transport/frame_settings.h
+++ b/src/core/ext/transport/chttp2/transport/frame_settings.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/transport/chttp2/transport/frame_window_update.c b/src/core/ext/transport/chttp2/transport/frame_window_update.c
index 8ed72dddca..682be2c89b 100644
--- a/src/core/ext/transport/chttp2/transport/frame_window_update.c
+++ b/src/core/ext/transport/chttp2/transport/frame_window_update.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -124,8 +109,7 @@ grpc_error *grpc_chttp2_window_update_parser_parse(
                                         received_update);
       bool is_zero = t->outgoing_window <= 0;
       if (was_zero && !is_zero) {
-        grpc_chttp2_initiate_write(exec_ctx, t, false,
-                                   "new_global_flow_control");
+        grpc_chttp2_initiate_write(exec_ctx, t, "new_global_flow_control");
       }
     }
   }
diff --git a/src/core/ext/transport/chttp2/transport/frame_window_update.h b/src/core/ext/transport/chttp2/transport/frame_window_update.h
index f75dfb3d87..698da4e351 100644
--- a/src/core/ext/transport/chttp2/transport/frame_window_update.h
+++ b/src/core/ext/transport/chttp2/transport/frame_window_update.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/transport/chttp2/transport/hpack_encoder.c b/src/core/ext/transport/chttp2/transport/hpack_encoder.c
index 126e012aac..a0e748e7b1 100644
--- a/src/core/ext/transport/chttp2/transport/hpack_encoder.c
+++ b/src/core/ext/transport/chttp2/transport/hpack_encoder.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -623,15 +608,14 @@ void grpc_chttp2_hpack_compressor_set_max_table_size(
 
 void grpc_chttp2_encode_header(grpc_exec_ctx *exec_ctx,
                                grpc_chttp2_hpack_compressor *c,
+                               grpc_mdelem **extra_headers,
+                               size_t extra_headers_size,
                                grpc_metadata_batch *metadata,
                                const grpc_encode_header_options *options,
                                grpc_slice_buffer *outbuf) {
-  framer_state st;
-  grpc_linked_mdelem *l;
-  gpr_timespec deadline;
-
   GPR_ASSERT(options->stream_id != 0);
 
+  framer_state st;
   st.seen_regular_header = 0;
   st.stream_id = options->stream_id;
   st.output = outbuf;
@@ -648,11 +632,14 @@ void grpc_chttp2_encode_header(grpc_exec_ctx *exec_ctx,
   if (c->advertise_table_size_change != 0) {
     emit_advertise_table_size_change(c, &st);
   }
+  for (size_t i = 0; i < extra_headers_size; ++i) {
+    hpack_enc(exec_ctx, c, *extra_headers[i], &st);
+  }
   grpc_metadata_batch_assert_ok(metadata);
-  for (l = metadata->list.head; l; l = l->next) {
+  for (grpc_linked_mdelem *l = metadata->list.head; l; l = l->next) {
     hpack_enc(exec_ctx, c, l->md, &st);
   }
-  deadline = metadata->deadline;
+  gpr_timespec deadline = metadata->deadline;
   if (gpr_time_cmp(deadline, gpr_inf_future(deadline.clock_type)) != 0) {
     deadline_enc(exec_ctx, c, deadline, &st);
   }
diff --git a/src/core/ext/transport/chttp2/transport/hpack_encoder.h b/src/core/ext/transport/chttp2/transport/hpack_encoder.h
index 6ce3209604..271192f894 100644
--- a/src/core/ext/transport/chttp2/transport/hpack_encoder.h
+++ b/src/core/ext/transport/chttp2/transport/hpack_encoder.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -100,6 +85,8 @@ typedef struct {
 
 void grpc_chttp2_encode_header(grpc_exec_ctx *exec_ctx,
                                grpc_chttp2_hpack_compressor *c,
+                               grpc_mdelem **extra_headers,
+                               size_t extra_headers_size,
                                grpc_metadata_batch *metadata,
                                const grpc_encode_header_options *options,
                                grpc_slice_buffer *outbuf);
diff --git a/src/core/ext/transport/chttp2/transport/hpack_parser.c b/src/core/ext/transport/chttp2/transport/hpack_parser.c
index bb98bc4a79..7f37365558 100644
--- a/src/core/ext/transport/chttp2/transport/hpack_parser.c
+++ b/src/core/ext/transport/chttp2/transport/hpack_parser.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -1664,7 +1649,7 @@ static void force_client_rst_stream(grpc_exec_ctx *exec_ctx, void *sp,
     grpc_slice_buffer_add(
         &t->qbuf, grpc_chttp2_rst_stream_create(s->id, GRPC_HTTP2_NO_ERROR,
                                                 &s->stats.outgoing));
-    grpc_chttp2_initiate_write(exec_ctx, t, false, "force_rst_stream");
+    grpc_chttp2_initiate_write(exec_ctx, t, "force_rst_stream");
     grpc_chttp2_mark_stream_closed(exec_ctx, t, s, true, true, GRPC_ERROR_NONE);
   }
   GRPC_CHTTP2_STREAM_UNREF(exec_ctx, s, "final_rst");
@@ -1711,10 +1696,10 @@ grpc_error *grpc_chttp2_header_parser_parse(grpc_exec_ctx *exec_ctx,
              however -- it might be that we receive a RST_STREAM following this
              and can avoid the extra write */
           GRPC_CHTTP2_STREAM_REF(s, "final_rst");
-          grpc_closure_sched(
-              exec_ctx, grpc_closure_create(force_client_rst_stream, s,
-                                            grpc_combiner_finally_scheduler(
-                                                t->combiner, false)),
+          GRPC_CLOSURE_SCHED(
+              exec_ctx,
+              GRPC_CLOSURE_CREATE(force_client_rst_stream, s,
+                                  grpc_combiner_finally_scheduler(t->combiner)),
               GRPC_ERROR_NONE);
         }
         grpc_chttp2_mark_stream_closed(exec_ctx, t, s, true, false,
diff --git a/src/core/ext/transport/chttp2/transport/hpack_parser.h b/src/core/ext/transport/chttp2/transport/hpack_parser.h
index a817183eb5..8fbc6a602b 100644
--- a/src/core/ext/transport/chttp2/transport/hpack_parser.h
+++ b/src/core/ext/transport/chttp2/transport/hpack_parser.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/transport/chttp2/transport/hpack_table.c b/src/core/ext/transport/chttp2/transport/hpack_table.c
index 7aaff55339..944d778011 100644
--- a/src/core/ext/transport/chttp2/transport/hpack_table.c
+++ b/src/core/ext/transport/chttp2/transport/hpack_table.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/transport/chttp2/transport/hpack_table.h b/src/core/ext/transport/chttp2/transport/hpack_table.h
index 32a0380e00..2cf8f68506 100644
--- a/src/core/ext/transport/chttp2/transport/hpack_table.h
+++ b/src/core/ext/transport/chttp2/transport/hpack_table.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/transport/chttp2/transport/http2_settings.c b/src/core/ext/transport/chttp2/transport/http2_settings.c
index d4905107ef..46b7c0c49c 100644
--- a/src/core/ext/transport/chttp2/transport/http2_settings.c
+++ b/src/core/ext/transport/chttp2/transport/http2_settings.c
@@ -1,32 +1,17 @@
 /*
- * Copyright 2017, Google Inc.
- * All rights reserved.
+ * Copyright 2017 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  */
 
 /*
diff --git a/src/core/ext/transport/chttp2/transport/http2_settings.h b/src/core/ext/transport/chttp2/transport/http2_settings.h
index 9781cdc989..706dfc3139 100644
--- a/src/core/ext/transport/chttp2/transport/http2_settings.h
+++ b/src/core/ext/transport/chttp2/transport/http2_settings.h
@@ -1,32 +1,17 @@
 /*
- * Copyright 2017, Google Inc.
- * All rights reserved.
+ * Copyright 2017 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  */
 
 /*
diff --git a/src/core/ext/transport/chttp2/transport/huffsyms.c b/src/core/ext/transport/chttp2/transport/huffsyms.c
index 68b34e4e2d..f28d8cc30a 100644
--- a/src/core/ext/transport/chttp2/transport/huffsyms.c
+++ b/src/core/ext/transport/chttp2/transport/huffsyms.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/transport/chttp2/transport/huffsyms.h b/src/core/ext/transport/chttp2/transport/huffsyms.h
index fee00954a0..2e2a5dacae 100644
--- a/src/core/ext/transport/chttp2/transport/huffsyms.h
+++ b/src/core/ext/transport/chttp2/transport/huffsyms.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/transport/chttp2/transport/incoming_metadata.c b/src/core/ext/transport/chttp2/transport/incoming_metadata.c
index da0a34d32a..cf0a9ca920 100644
--- a/src/core/ext/transport/chttp2/transport/incoming_metadata.c
+++ b/src/core/ext/transport/chttp2/transport/incoming_metadata.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/transport/chttp2/transport/incoming_metadata.h b/src/core/ext/transport/chttp2/transport/incoming_metadata.h
index 288c917e65..a951d8764c 100644
--- a/src/core/ext/transport/chttp2/transport/incoming_metadata.h
+++ b/src/core/ext/transport/chttp2/transport/incoming_metadata.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/transport/chttp2/transport/internal.h b/src/core/ext/transport/chttp2/transport/internal.h
index 9eed73cd71..44ea3bdc61 100644
--- a/src/core/ext/transport/chttp2/transport/internal.h
+++ b/src/core/ext/transport/chttp2/transport/internal.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -48,6 +33,7 @@
 #include "src/core/ext/transport/chttp2/transport/hpack_parser.h"
 #include "src/core/ext/transport/chttp2/transport/incoming_metadata.h"
 #include "src/core/ext/transport/chttp2/transport/stream_map.h"
+#include "src/core/lib/compression/stream_compression.h"
 #include "src/core/lib/iomgr/combiner.h"
 #include "src/core/lib/iomgr/endpoint.h"
 #include "src/core/lib/iomgr/timer.h"
@@ -73,7 +59,6 @@ typedef enum {
   GRPC_CHTTP2_WRITE_STATE_IDLE,
   GRPC_CHTTP2_WRITE_STATE_WRITING,
   GRPC_CHTTP2_WRITE_STATE_WRITING_WITH_MORE,
-  GRPC_CHTTP2_WRITE_STATE_WRITING_WITH_MORE_AND_COVERED_BY_POLLER,
 } grpc_chttp2_write_state;
 
 typedef enum {
@@ -83,6 +68,11 @@ typedef enum {
 } grpc_chttp2_ping_type;
 
 typedef enum {
+  GRPC_CHTTP2_OPTIMIZE_FOR_LATENCY,
+  GRPC_CHTTP2_OPTIMIZE_FOR_THROUGHPUT,
+} grpc_chttp2_optimization_target;
+
+typedef enum {
   GRPC_CHTTP2_PCL_INITIATE = 0,
   GRPC_CHTTP2_PCL_NEXT,
   GRPC_CHTTP2_PCL_INFLIGHT,
@@ -245,6 +235,8 @@ struct grpc_chttp2_transport {
   /** should we probe bdp? */
   bool enable_bdp_probe;
 
+  grpc_chttp2_optimization_target opt_target;
+
   /** various lists of streams */
   grpc_chttp2_stream_list lists[STREAM_LIST_COUNT];
 
@@ -458,12 +450,12 @@ struct grpc_chttp2_stream {
   grpc_slice fetching_slice;
   int64_t next_message_end_offset;
   int64_t flow_controlled_bytes_written;
-  bool complete_fetch_covered_by_poller;
   grpc_closure complete_fetch_locked;
   grpc_closure *fetching_send_message_finished;
 
   grpc_metadata_batch *recv_initial_metadata;
   grpc_closure *recv_initial_metadata_ready;
+  bool *trailing_metadata_available;
   grpc_byte_stream **recv_message;
   grpc_closure *recv_message_ready;
   grpc_metadata_batch *recv_trailing_metadata;
@@ -549,8 +541,7 @@ struct grpc_chttp2_stream {
     The actual call chain is documented in the implementation of this function.
     */
 void grpc_chttp2_initiate_write(grpc_exec_ctx *exec_ctx,
-                                grpc_chttp2_transport *t,
-                                bool covered_by_poller, const char *reason);
+                                grpc_chttp2_transport *t, const char *reason);
 
 typedef enum {
   GRPC_CHTTP2_NOTHING_TO_WRITE,
@@ -766,7 +757,7 @@ void grpc_chttp2_mark_stream_closed(grpc_exec_ctx *exec_ctx,
 void grpc_chttp2_start_writing(grpc_exec_ctx *exec_ctx,
                                grpc_chttp2_transport *t);
 
-#ifdef GRPC_STREAM_REFCOUNT_DEBUG
+#ifndef NDEBUG
 #define GRPC_CHTTP2_STREAM_REF(stream, reason) \
   grpc_chttp2_stream_ref(stream, reason)
 #define GRPC_CHTTP2_STREAM_UNREF(exec_ctx, stream, reason) \
@@ -782,8 +773,7 @@ void grpc_chttp2_stream_ref(grpc_chttp2_stream *s);
 void grpc_chttp2_stream_unref(grpc_exec_ctx *exec_ctx, grpc_chttp2_stream *s);
 #endif
 
-//#define GRPC_CHTTP2_REFCOUNTING_DEBUG 1
-#ifdef GRPC_CHTTP2_REFCOUNTING_DEBUG
+#ifndef NDEBUG
 #define GRPC_CHTTP2_REF_TRANSPORT(t, r) \
   grpc_chttp2_ref_transport(t, r, __FILE__, __LINE__)
 #define GRPC_CHTTP2_UNREF_TRANSPORT(cl, t, r) \
diff --git a/src/core/ext/transport/chttp2/transport/parsing.c b/src/core/ext/transport/chttp2/transport/parsing.c
index 1a676e2259..3c8b470b4f 100644
--- a/src/core/ext/transport/chttp2/transport/parsing.c
+++ b/src/core/ext/transport/chttp2/transport/parsing.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -433,7 +418,7 @@ static grpc_error *update_incoming_window(grpc_exec_ctx *exec_ctx,
   GRPC_CHTTP2_FLOW_DEBIT_TRANSPORT("parse", t, incoming_window,
                                    incoming_frame_size);
   if (t->incoming_window <= target_incoming_window / 2) {
-    grpc_chttp2_initiate_write(exec_ctx, t, false, "flow_control");
+    grpc_chttp2_initiate_write(exec_ctx, t, "flow_control");
   }
 
   return GRPC_ERROR_NONE;
@@ -696,9 +681,19 @@ static grpc_error *init_header_frame_parser(grpc_exec_ctx *exec_ctx,
   t->parser_data = &t->hpack_parser;
   switch (s->header_frames_received) {
     case 0:
-      t->hpack_parser.on_header = on_initial_header;
+      if (t->is_client && t->header_eof) {
+        GRPC_CHTTP2_IF_TRACING(gpr_log(GPR_INFO, "parsing Trailers-Only"));
+        if (s->trailing_metadata_available != NULL) {
+          *s->trailing_metadata_available = true;
+        }
+        t->hpack_parser.on_header = on_trailing_header;
+      } else {
+        GRPC_CHTTP2_IF_TRACING(gpr_log(GPR_INFO, "parsing initial_metadata"));
+        t->hpack_parser.on_header = on_initial_header;
+      }
       break;
     case 1:
+      GRPC_CHTTP2_IF_TRACING(gpr_log(GPR_INFO, "parsing trailing_metadata"));
       t->hpack_parser.on_header = on_trailing_header;
       break;
     case 2:
diff --git a/src/core/ext/transport/chttp2/transport/stream_lists.c b/src/core/ext/transport/chttp2/transport/stream_lists.c
index 078818fb18..1bf5b34510 100644
--- a/src/core/ext/transport/chttp2/transport/stream_lists.c
+++ b/src/core/ext/transport/chttp2/transport/stream_lists.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/transport/chttp2/transport/stream_map.c b/src/core/ext/transport/chttp2/transport/stream_map.c
index 5f5a28446d..e2f10bc208 100644
--- a/src/core/ext/transport/chttp2/transport/stream_map.c
+++ b/src/core/ext/transport/chttp2/transport/stream_map.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/transport/chttp2/transport/stream_map.h b/src/core/ext/transport/chttp2/transport/stream_map.h
index 203f640680..30c50ba32e 100644
--- a/src/core/ext/transport/chttp2/transport/stream_map.h
+++ b/src/core/ext/transport/chttp2/transport/stream_map.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/transport/chttp2/transport/varint.c b/src/core/ext/transport/chttp2/transport/varint.c
index e434ad3c07..5f93a23a94 100644
--- a/src/core/ext/transport/chttp2/transport/varint.c
+++ b/src/core/ext/transport/chttp2/transport/varint.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/transport/chttp2/transport/varint.h b/src/core/ext/transport/chttp2/transport/varint.h
index 450e5fd119..5a2b670f06 100644
--- a/src/core/ext/transport/chttp2/transport/varint.h
+++ b/src/core/ext/transport/chttp2/transport/varint.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/transport/chttp2/transport/writing.c b/src/core/ext/transport/chttp2/transport/writing.c
index 1ab94ca54f..3e16fda6dc 100644
--- a/src/core/ext/transport/chttp2/transport/writing.c
+++ b/src/core/ext/transport/chttp2/transport/writing.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -125,7 +110,7 @@ static void maybe_initiate_ping(grpc_exec_ctx *exec_ctx,
   }
   pq->inflight_id = t->ping_ctr * GRPC_CHTTP2_PING_TYPE_COUNT + ping_type;
   t->ping_ctr++;
-  grpc_closure_list_sched(exec_ctx, &pq->lists[GRPC_CHTTP2_PCL_INITIATE]);
+  GRPC_CLOSURE_LIST_SCHED(exec_ctx, &pq->lists[GRPC_CHTTP2_PCL_INITIATE]);
   grpc_closure_list_move(&pq->lists[GRPC_CHTTP2_PCL_NEXT],
                          &pq->lists[GRPC_CHTTP2_PCL_INFLIGHT]);
   grpc_slice_buffer_add(&t->outbuf,
@@ -176,6 +161,20 @@ static uint32_t target_write_size(grpc_chttp2_transport *t) {
   return 1024 * 1024;
 }
 
+// Returns true if initial_metadata contains only default headers.
+//
+// TODO(roth): The fact that we hard-code these particular headers here
+// is fairly ugly.  Need some better way to know which headers are
+// default, maybe via a bit in the static metadata table?
+static bool is_default_initial_metadata(grpc_metadata_batch *initial_metadata) {
+  int num_default_fields =
+      (initial_metadata->idx.named.status != NULL) +
+      (initial_metadata->idx.named.content_type != NULL) +
+      (initial_metadata->idx.named.grpc_encoding != NULL) +
+      (initial_metadata->idx.named.grpc_accept_encoding != NULL);
+  return (size_t)num_default_fields == initial_metadata->list.count;
+}
+
 grpc_chttp2_begin_write_result grpc_chttp2_begin_write(
     grpc_exec_ctx *exec_ctx, grpc_chttp2_transport *t) {
   grpc_chttp2_stream *s;
@@ -205,8 +204,7 @@ grpc_chttp2_begin_write_result grpc_chttp2_begin_write(
     while (grpc_chttp2_list_pop_stalled_by_transport(t, &s)) {
       if (!t->closed && grpc_chttp2_list_add_writable_stream(t, s) &&
           stream_ref_if_not_destroyed(&s->refcount->refs)) {
-        grpc_chttp2_initiate_write(exec_ctx, t, false,
-                                   "transport.read_flow_control");
+        grpc_chttp2_initiate_write(exec_ctx, t, "transport.read_flow_control");
       }
     }
   }
@@ -233,31 +231,61 @@ grpc_chttp2_begin_write_result grpc_chttp2_begin_write(
         t->is_client ? "CLIENT" : "SERVER", s->id, sent_initial_metadata,
         s->send_initial_metadata != NULL, s->announce_window));
 
+    grpc_mdelem *extra_headers_for_trailing_metadata[2];
+    size_t num_extra_headers_for_trailing_metadata = 0;
+
     /* send initial metadata if it's available */
-    if (!sent_initial_metadata && s->send_initial_metadata) {
-      grpc_encode_header_options hopt = {
-          .stream_id = s->id,
-          .is_eof = false,
-          .use_true_binary_metadata =
-              t->settings
-                  [GRPC_PEER_SETTINGS]
-                  [GRPC_CHTTP2_SETTINGS_GRPC_ALLOW_TRUE_BINARY_METADATA] != 0,
-          .max_frame_size = t->settings[GRPC_PEER_SETTINGS]
-                                       [GRPC_CHTTP2_SETTINGS_MAX_FRAME_SIZE],
-          .stats = &s->stats.outgoing};
-      grpc_chttp2_encode_header(exec_ctx, &t->hpack_compressor,
-                                s->send_initial_metadata, &hopt, &t->outbuf);
+    if (!sent_initial_metadata && s->send_initial_metadata != NULL) {
+      // We skip this on the server side if there is no custom initial
+      // metadata, there are no messages to send, and we are also sending
+      // trailing metadata.  This results in a Trailers-Only response,
+      // which is required for retries, as per:
+      // https://github.com/grpc/proposal/blob/master/A6-client-retries.md#when-retries-are-valid
+      if (t->is_client || s->fetching_send_message != NULL ||
+          s->flow_controlled_buffer.length != 0 ||
+          s->send_trailing_metadata == NULL ||
+          !is_default_initial_metadata(s->send_initial_metadata)) {
+        grpc_encode_header_options hopt = {
+            .stream_id = s->id,
+            .is_eof = false,
+            .use_true_binary_metadata =
+                t->settings
+                    [GRPC_PEER_SETTINGS]
+                    [GRPC_CHTTP2_SETTINGS_GRPC_ALLOW_TRUE_BINARY_METADATA] != 0,
+            .max_frame_size = t->settings[GRPC_PEER_SETTINGS]
+                                         [GRPC_CHTTP2_SETTINGS_MAX_FRAME_SIZE],
+            .stats = &s->stats.outgoing};
+        grpc_chttp2_encode_header(exec_ctx, &t->hpack_compressor, NULL, 0,
+                                  s->send_initial_metadata, &hopt, &t->outbuf);
+        now_writing = true;
+        t->ping_state.pings_before_data_required =
+            t->ping_policy.max_pings_without_data;
+        if (!t->is_client) {
+          t->ping_recv_state.last_ping_recv_time =
+              gpr_inf_past(GPR_CLOCK_MONOTONIC);
+          t->ping_recv_state.ping_strikes = 0;
+        }
+      } else {
+        GRPC_CHTTP2_IF_TRACING(
+            gpr_log(GPR_INFO, "not sending initial_metadata (Trailers-Only)"));
+        // When sending Trailers-Only, we need to move the :status and
+        // content-type headers to the trailers.
+        if (s->send_initial_metadata->idx.named.status != NULL) {
+          extra_headers_for_trailing_metadata
+              [num_extra_headers_for_trailing_metadata++] =
+                  &s->send_initial_metadata->idx.named.status->md;
+        }
+        if (s->send_initial_metadata->idx.named.content_type != NULL) {
+          extra_headers_for_trailing_metadata
+              [num_extra_headers_for_trailing_metadata++] =
+                  &s->send_initial_metadata->idx.named.content_type->md;
+        }
+      }
       s->send_initial_metadata = NULL;
       s->sent_initial_metadata = true;
       sent_initial_metadata = true;
-      now_writing = true;
-      t->ping_state.pings_before_data_required =
-          t->ping_policy.max_pings_without_data;
-      if (!t->is_client) {
-        t->ping_recv_state.last_ping_recv_time = 0;
-        t->ping_recv_state.ping_strikes = 0;
-      }
     }
+
     /* send any window updates */
     if (s->announce_window > 0) {
       uint32_t announce = s->announce_window;
@@ -332,6 +360,7 @@ grpc_chttp2_begin_write_result grpc_chttp2_begin_write(
       if (s->send_trailing_metadata != NULL &&
           s->fetching_send_message == NULL &&
           s->flow_controlled_buffer.length == 0) {
+        GRPC_CHTTP2_IF_TRACING(gpr_log(GPR_INFO, "sending trailing_metadata"));
         if (grpc_metadata_batch_is_empty(s->send_trailing_metadata)) {
           grpc_chttp2_encode_data(s->id, &s->flow_controlled_buffer, 0, true,
                                   &s->stats.outgoing, &t->outbuf);
@@ -349,6 +378,8 @@ grpc_chttp2_begin_write_result grpc_chttp2_begin_write(
                              [GRPC_CHTTP2_SETTINGS_MAX_FRAME_SIZE],
               .stats = &s->stats.outgoing};
           grpc_chttp2_encode_header(exec_ctx, &t->hpack_compressor,
+                                    extra_headers_for_trailing_metadata,
+                                    num_extra_headers_for_trailing_metadata,
                                     s->send_trailing_metadata, &hopt,
                                     &t->outbuf);
         }
diff --git a/src/core/ext/transport/cronet/client/secure/cronet_channel_create.c b/src/core/ext/transport/cronet/client/secure/cronet_channel_create.c
index b6e9e845df..83365192e3 100644
--- a/src/core/ext/transport/cronet/client/secure/cronet_channel_create.c
+++ b/src/core/ext/transport/cronet/client/secure/cronet_channel_create.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/transport/cronet/transport/cronet_api_dummy.c b/src/core/ext/transport/cronet/transport/cronet_api_dummy.c
index 0dc6a5152f..4f248ad919 100644
--- a/src/core/ext/transport/cronet/transport/cronet_api_dummy.c
+++ b/src/core/ext/transport/cronet/transport/cronet_api_dummy.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/transport/cronet/transport/cronet_transport.c b/src/core/ext/transport/cronet/transport/cronet_transport.c
index 67974b0b6a..29dfa885de 100644
--- a/src/core/ext/transport/cronet/transport/cronet_transport.c
+++ b/src/core/ext/transport/cronet/transport/cronet_transport.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -781,20 +766,50 @@ static bool op_can_be_run(grpc_transport_stream_op_batch *curr_op,
   bool is_canceled_or_failed = stream_state->state_op_done[OP_CANCEL_ERROR] ||
                                stream_state->state_callback_received[OP_FAILED];
   if (is_canceled_or_failed) {
-    if (op_id == OP_SEND_INITIAL_METADATA) result = false;
-    if (op_id == OP_SEND_MESSAGE) result = false;
-    if (op_id == OP_SEND_TRAILING_METADATA) result = false;
-    if (op_id == OP_CANCEL_ERROR) result = false;
+    if (op_id == OP_SEND_INITIAL_METADATA) {
+      CRONET_LOG(GPR_DEBUG, "Because");
+      result = false;
+    }
+    if (op_id == OP_SEND_MESSAGE) {
+      CRONET_LOG(GPR_DEBUG, "Because");
+      result = false;
+    }
+    if (op_id == OP_SEND_TRAILING_METADATA) {
+      CRONET_LOG(GPR_DEBUG, "Because");
+      result = false;
+    }
+    if (op_id == OP_CANCEL_ERROR) {
+      CRONET_LOG(GPR_DEBUG, "Because");
+      result = false;
+    }
     /* already executed */
     if (op_id == OP_RECV_INITIAL_METADATA &&
-        stream_state->state_op_done[OP_RECV_INITIAL_METADATA])
+        stream_state->state_op_done[OP_RECV_INITIAL_METADATA]) {
+      CRONET_LOG(GPR_DEBUG, "Because");
       result = false;
-    if (op_id == OP_RECV_MESSAGE &&
-        stream_state->state_op_done[OP_RECV_MESSAGE])
+    }
+    if (op_id == OP_RECV_MESSAGE && op_state->state_op_done[OP_RECV_MESSAGE]) {
+      CRONET_LOG(GPR_DEBUG, "Because");
       result = false;
+    }
     if (op_id == OP_RECV_TRAILING_METADATA &&
-        stream_state->state_op_done[OP_RECV_TRAILING_METADATA])
+        stream_state->state_op_done[OP_RECV_TRAILING_METADATA]) {
+      CRONET_LOG(GPR_DEBUG, "Because");
       result = false;
+    }
+    /* ON_COMPLETE can be processed if one of the following conditions is met:
+     * 1. the stream failed
+     * 2. the stream is cancelled, and the callback is received
+     * 3. the stream succeeded before cancel is effective
+     * 4. the stream is cancelled, and the stream is never started */
+    if (op_id == OP_ON_COMPLETE &&
+        !(stream_state->state_callback_received[OP_FAILED] ||
+          stream_state->state_callback_received[OP_CANCELED] ||
+          stream_state->state_callback_received[OP_SUCCEEDED] ||
+          !stream_state->state_op_done[OP_SEND_INITIAL_METADATA])) {
+      CRONET_LOG(GPR_DEBUG, "Because");
+      result = false;
+    }
   } else if (op_id == OP_SEND_INITIAL_METADATA) {
     /* already executed */
     if (stream_state->state_op_done[OP_SEND_INITIAL_METADATA]) result = false;
@@ -883,7 +898,7 @@ static bool op_can_be_run(grpc_transport_stream_op_batch *curr_op,
       CRONET_LOG(GPR_DEBUG, "Because");
       result = false;
     } else if (curr_op->recv_message &&
-               !stream_state->state_op_done[OP_RECV_MESSAGE]) {
+               !op_state->state_op_done[OP_RECV_MESSAGE]) {
       CRONET_LOG(GPR_DEBUG, "Because");
       result = false;
     } else if (curr_op->cancel_stream &&
@@ -1048,17 +1063,17 @@ static enum e_op_result execute_stream_op(grpc_exec_ctx *exec_ctx,
                            OP_RECV_INITIAL_METADATA)) {
     CRONET_LOG(GPR_DEBUG, "running: %p  OP_RECV_INITIAL_METADATA", oas);
     if (stream_state->state_op_done[OP_CANCEL_ERROR]) {
-      grpc_closure_sched(
+      GRPC_CLOSURE_SCHED(
           exec_ctx,
           stream_op->payload->recv_initial_metadata.recv_initial_metadata_ready,
           GRPC_ERROR_NONE);
     } else if (stream_state->state_callback_received[OP_FAILED]) {
-      grpc_closure_sched(
+      GRPC_CLOSURE_SCHED(
           exec_ctx,
           stream_op->payload->recv_initial_metadata.recv_initial_metadata_ready,
           GRPC_ERROR_NONE);
     } else if (stream_state->state_op_done[OP_RECV_TRAILING_METADATA]) {
-      grpc_closure_sched(
+      GRPC_CLOSURE_SCHED(
           exec_ctx,
           stream_op->payload->recv_initial_metadata.recv_initial_metadata_ready,
           GRPC_ERROR_NONE);
@@ -1066,7 +1081,7 @@ static enum e_op_result execute_stream_op(grpc_exec_ctx *exec_ctx,
       grpc_chttp2_incoming_metadata_buffer_publish(
           exec_ctx, &oas->s->state.rs.initial_metadata,
           stream_op->payload->recv_initial_metadata.recv_initial_metadata);
-      grpc_closure_sched(
+      GRPC_CLOSURE_SCHED(
           exec_ctx,
           stream_op->payload->recv_initial_metadata.recv_initial_metadata_ready,
           GRPC_ERROR_NONE);
@@ -1078,22 +1093,24 @@ static enum e_op_result execute_stream_op(grpc_exec_ctx *exec_ctx,
     CRONET_LOG(GPR_DEBUG, "running: %p  OP_RECV_MESSAGE", oas);
     if (stream_state->state_op_done[OP_CANCEL_ERROR]) {
       CRONET_LOG(GPR_DEBUG, "Stream is cancelled.");
-      grpc_closure_sched(exec_ctx,
+      GRPC_CLOSURE_SCHED(exec_ctx,
                          stream_op->payload->recv_message.recv_message_ready,
                          GRPC_ERROR_NONE);
       stream_state->state_op_done[OP_RECV_MESSAGE] = true;
+      oas->state.state_op_done[OP_RECV_MESSAGE] = true;
       result = ACTION_TAKEN_NO_CALLBACK;
     } else if (stream_state->state_callback_received[OP_FAILED]) {
       CRONET_LOG(GPR_DEBUG, "Stream failed.");
-      grpc_closure_sched(exec_ctx,
+      GRPC_CLOSURE_SCHED(exec_ctx,
                          stream_op->payload->recv_message.recv_message_ready,
                          GRPC_ERROR_NONE);
       stream_state->state_op_done[OP_RECV_MESSAGE] = true;
+      oas->state.state_op_done[OP_RECV_MESSAGE] = true;
       result = ACTION_TAKEN_NO_CALLBACK;
     } else if (stream_state->rs.read_stream_closed == true) {
       /* No more data will be received */
       CRONET_LOG(GPR_DEBUG, "read stream closed");
-      grpc_closure_sched(exec_ctx,
+      GRPC_CLOSURE_SCHED(exec_ctx,
                          stream_op->payload->recv_message.recv_message_ready,
                          GRPC_ERROR_NONE);
       stream_state->state_op_done[OP_RECV_MESSAGE] = true;
@@ -1101,7 +1118,7 @@ static enum e_op_result execute_stream_op(grpc_exec_ctx *exec_ctx,
       result = ACTION_TAKEN_NO_CALLBACK;
     } else if (stream_state->flush_read) {
       CRONET_LOG(GPR_DEBUG, "flush read");
-      grpc_closure_sched(exec_ctx,
+      GRPC_CLOSURE_SCHED(exec_ctx,
                          stream_op->payload->recv_message.recv_message_ready,
                          GRPC_ERROR_NONE);
       stream_state->state_op_done[OP_RECV_MESSAGE] = true;
@@ -1142,7 +1159,7 @@ static enum e_op_result execute_stream_op(grpc_exec_ctx *exec_ctx,
           *((grpc_byte_buffer **)
                 stream_op->payload->recv_message.recv_message) =
               (grpc_byte_buffer *)&stream_state->rs.sbs;
-          grpc_closure_sched(
+          GRPC_CLOSURE_SCHED(
               exec_ctx, stream_op->payload->recv_message.recv_message_ready,
               GRPC_ERROR_NONE);
           stream_state->state_op_done[OP_RECV_MESSAGE] = true;
@@ -1196,7 +1213,7 @@ static enum e_op_result execute_stream_op(grpc_exec_ctx *exec_ctx,
       }
       *((grpc_byte_buffer **)stream_op->payload->recv_message.recv_message) =
           (grpc_byte_buffer *)&stream_state->rs.sbs;
-      grpc_closure_sched(exec_ctx,
+      GRPC_CLOSURE_SCHED(exec_ctx,
                          stream_op->payload->recv_message.recv_message_ready,
                          GRPC_ERROR_NONE);
       stream_state->state_op_done[OP_RECV_MESSAGE] = true;
@@ -1229,8 +1246,8 @@ static enum e_op_result execute_stream_op(grpc_exec_ctx *exec_ctx,
   } else if (stream_op->cancel_stream &&
              op_can_be_run(stream_op, s, &oas->state, OP_CANCEL_ERROR)) {
     CRONET_LOG(GPR_DEBUG, "running: %p  OP_CANCEL_ERROR", oas);
-    CRONET_LOG(GPR_DEBUG, "W: bidirectional_stream_cancel(%p)", s->cbs);
     if (s->cbs) {
+      CRONET_LOG(GPR_DEBUG, "W: bidirectional_stream_cancel(%p)", s->cbs);
       bidirectional_stream_cancel(s->cbs);
       result = ACTION_TAKEN_WITH_CALLBACK;
     } else {
@@ -1245,17 +1262,17 @@ static enum e_op_result execute_stream_op(grpc_exec_ctx *exec_ctx,
              op_can_be_run(stream_op, s, &oas->state, OP_ON_COMPLETE)) {
     CRONET_LOG(GPR_DEBUG, "running: %p  OP_ON_COMPLETE", oas);
     if (stream_state->state_op_done[OP_CANCEL_ERROR]) {
-      grpc_closure_sched(exec_ctx, stream_op->on_complete,
+      GRPC_CLOSURE_SCHED(exec_ctx, stream_op->on_complete,
                          GRPC_ERROR_REF(stream_state->cancel_error));
     } else if (stream_state->state_callback_received[OP_FAILED]) {
-      grpc_closure_sched(
+      GRPC_CLOSURE_SCHED(
           exec_ctx, stream_op->on_complete,
           make_error_with_desc(GRPC_STATUS_UNAVAILABLE, "Unavailable."));
     } else {
       /* All actions in this stream_op are complete. Call the on_complete
        * callback
        */
-      grpc_closure_sched(exec_ctx, stream_op->on_complete, GRPC_ERROR_NONE);
+      GRPC_CLOSURE_SCHED(exec_ctx, stream_op->on_complete, GRPC_ERROR_NONE);
     }
     oas->state.state_op_done[OP_ON_COMPLETE] = true;
     oas->done = true;
@@ -1327,16 +1344,16 @@ static void perform_stream_op(grpc_exec_ctx *exec_ctx, grpc_transport *gt,
     /* Cronet does not support :authority header field. We cancel the call when
      this field is present in metadata */
     if (op->recv_initial_metadata) {
-      grpc_closure_sched(
+      GRPC_CLOSURE_SCHED(
           exec_ctx,
           op->payload->recv_initial_metadata.recv_initial_metadata_ready,
           GRPC_ERROR_CANCELLED);
     }
     if (op->recv_message) {
-      grpc_closure_sched(exec_ctx, op->payload->recv_message.recv_message_ready,
+      GRPC_CLOSURE_SCHED(exec_ctx, op->payload->recv_message.recv_message_ready,
                          GRPC_ERROR_CANCELLED);
     }
-    grpc_closure_sched(exec_ctx, op->on_complete, GRPC_ERROR_CANCELLED);
+    GRPC_CLOSURE_SCHED(exec_ctx, op->on_complete, GRPC_ERROR_CANCELLED);
     return;
   }
   stream_obj *s = (stream_obj *)gs;
@@ -1350,7 +1367,7 @@ static void destroy_stream(grpc_exec_ctx *exec_ctx, grpc_transport *gt,
   stream_obj *s = (stream_obj *)gs;
   null_and_maybe_free_read_buffer(s);
   GRPC_ERROR_UNREF(s->state.cancel_error);
-  grpc_closure_sched(exec_ctx, then_schedule_closure, GRPC_ERROR_NONE);
+  GRPC_CLOSURE_SCHED(exec_ctx, then_schedule_closure, GRPC_ERROR_NONE);
 }
 
 static void destroy_transport(grpc_exec_ctx *exec_ctx, grpc_transport *gt) {}
diff --git a/src/core/ext/transport/cronet/transport/cronet_transport.h b/src/core/ext/transport/cronet/transport/cronet_transport.h
index 169ce31fd7..3bd4249b79 100644
--- a/src/core/ext/transport/cronet/transport/cronet_transport.h
+++ b/src/core/ext/transport/cronet/transport/cronet_transport.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/ext/transport/inproc/inproc_plugin.c b/src/core/ext/transport/inproc/inproc_plugin.c
new file mode 100644
index 0000000000..6a796a0b19
--- /dev/null
+++ b/src/core/ext/transport/inproc/inproc_plugin.c
@@ -0,0 +1,29 @@
+/*
+ *
+ * Copyright 2017 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+#include "src/core/ext/transport/inproc/inproc_transport.h"
+#include "src/core/lib/debug/trace.h"
+
+grpc_tracer_flag grpc_inproc_trace = GRPC_TRACER_INITIALIZER(false, "inproc");
+
+void grpc_inproc_plugin_init(void) {
+  grpc_register_tracer(&grpc_inproc_trace);
+  grpc_inproc_transport_init();
+}
+
+void grpc_inproc_plugin_shutdown(void) { grpc_inproc_transport_shutdown(); }
diff --git a/src/core/ext/transport/inproc/inproc_transport.c b/src/core/ext/transport/inproc/inproc_transport.c
new file mode 100644
index 0000000000..4df64d81e2
--- /dev/null
+++ b/src/core/ext/transport/inproc/inproc_transport.c
@@ -0,0 +1,1277 @@
+/*
+ *
+ * Copyright 2017 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+#include "src/core/ext/transport/inproc/inproc_transport.h"
+#include <grpc/support/alloc.h>
+#include <grpc/support/string_util.h>
+#include <grpc/support/sync.h>
+#include <grpc/support/time.h>
+#include <string.h>
+#include "src/core/lib/channel/channel_args.h"
+#include "src/core/lib/slice/slice_internal.h"
+#include "src/core/lib/surface/api_trace.h"
+#include "src/core/lib/surface/channel.h"
+#include "src/core/lib/surface/channel_stack_type.h"
+#include "src/core/lib/surface/server.h"
+#include "src/core/lib/transport/connectivity_state.h"
+#include "src/core/lib/transport/error_utils.h"
+#include "src/core/lib/transport/transport_impl.h"
+
+#define INPROC_LOG(...)                                          \
+  do {                                                           \
+    if (GRPC_TRACER_ON(grpc_inproc_trace)) gpr_log(__VA_ARGS__); \
+  } while (0)
+
+static const grpc_transport_vtable inproc_vtable;
+static grpc_slice g_empty_slice;
+static grpc_slice g_fake_path_key;
+static grpc_slice g_fake_path_value;
+static grpc_slice g_fake_auth_key;
+static grpc_slice g_fake_auth_value;
+
+typedef struct {
+  gpr_mu mu;
+  gpr_refcount refs;
+} shared_mu;
+
+typedef struct inproc_transport {
+  grpc_transport base;
+  shared_mu *mu;
+  gpr_refcount refs;
+  bool is_client;
+  grpc_connectivity_state_tracker connectivity;
+  void (*accept_stream_cb)(grpc_exec_ctx *exec_ctx, void *user_data,
+                           grpc_transport *transport, const void *server_data);
+  void *accept_stream_data;
+  bool is_closed;
+  struct inproc_transport *other_side;
+  struct inproc_stream *stream_list;
+} inproc_transport;
+
+typedef struct sb_list_entry {
+  grpc_slice_buffer sb;
+  struct sb_list_entry *next;
+} sb_list_entry;
+
+// Specialize grpc_byte_stream for our use case
+typedef struct {
+  grpc_byte_stream base;
+  sb_list_entry *le;
+} inproc_slice_byte_stream;
+
+typedef struct {
+  // TODO (vjpai): Add some inlined elements to avoid alloc in simple cases
+  sb_list_entry *head;
+  sb_list_entry *tail;
+} slice_buffer_list;
+
+static void slice_buffer_list_init(slice_buffer_list *l) {
+  l->head = NULL;
+  l->tail = NULL;
+}
+
+static void sb_list_entry_destroy(grpc_exec_ctx *exec_ctx, sb_list_entry *le) {
+  grpc_slice_buffer_destroy_internal(exec_ctx, &le->sb);
+  gpr_free(le);
+}
+
+static void slice_buffer_list_destroy(grpc_exec_ctx *exec_ctx,
+                                      slice_buffer_list *l) {
+  sb_list_entry *curr = l->head;
+  while (curr != NULL) {
+    sb_list_entry *le = curr;
+    curr = curr->next;
+    sb_list_entry_destroy(exec_ctx, le);
+  }
+  l->head = NULL;
+  l->tail = NULL;
+}
+
+static bool slice_buffer_list_empty(slice_buffer_list *l) {
+  return l->head == NULL;
+}
+
+static void slice_buffer_list_append_entry(slice_buffer_list *l,
+                                           sb_list_entry *next) {
+  next->next = NULL;
+  if (l->tail) {
+    l->tail->next = next;
+    l->tail = next;
+  } else {
+    l->head = next;
+    l->tail = next;
+  }
+}
+
+static grpc_slice_buffer *slice_buffer_list_append(slice_buffer_list *l) {
+  sb_list_entry *next = gpr_malloc(sizeof(*next));
+  grpc_slice_buffer_init(&next->sb);
+  slice_buffer_list_append_entry(l, next);
+  return &next->sb;
+}
+
+static sb_list_entry *slice_buffer_list_pophead(slice_buffer_list *l) {
+  sb_list_entry *ret = l->head;
+  l->head = l->head->next;
+  if (l->head == NULL) {
+    l->tail = NULL;
+  }
+  return ret;
+}
+
+typedef struct inproc_stream {
+  inproc_transport *t;
+  grpc_metadata_batch to_read_initial_md;
+  uint32_t to_read_initial_md_flags;
+  bool to_read_initial_md_filled;
+  slice_buffer_list to_read_message;
+  grpc_metadata_batch to_read_trailing_md;
+  bool to_read_trailing_md_filled;
+  bool reads_needed;
+  bool read_closure_scheduled;
+  grpc_closure read_closure;
+  // Write buffer used only during gap at init time when client-side
+  // stream is set up but server side stream is not yet set up
+  grpc_metadata_batch write_buffer_initial_md;
+  bool write_buffer_initial_md_filled;
+  uint32_t write_buffer_initial_md_flags;
+  gpr_timespec write_buffer_deadline;
+  slice_buffer_list write_buffer_message;
+  grpc_metadata_batch write_buffer_trailing_md;
+  bool write_buffer_trailing_md_filled;
+  grpc_error *write_buffer_cancel_error;
+
+  struct inproc_stream *other_side;
+  bool other_side_closed;               // won't talk anymore
+  bool write_buffer_other_side_closed;  // on hold
+  grpc_stream_refcount *refs;
+  grpc_closure *closure_at_destroy;
+
+  gpr_arena *arena;
+
+  grpc_transport_stream_op_batch *recv_initial_md_op;
+  grpc_transport_stream_op_batch *recv_message_op;
+  grpc_transport_stream_op_batch *recv_trailing_md_op;
+
+  inproc_slice_byte_stream recv_message_stream;
+
+  bool initial_md_sent;
+  bool trailing_md_sent;
+  bool initial_md_recvd;
+  bool trailing_md_recvd;
+
+  bool closed;
+
+  grpc_error *cancel_self_error;
+  grpc_error *cancel_other_error;
+
+  gpr_timespec deadline;
+
+  bool listed;
+  struct inproc_stream *stream_list_prev;
+  struct inproc_stream *stream_list_next;
+} inproc_stream;
+
+static bool inproc_slice_byte_stream_next(grpc_exec_ctx *exec_ctx,
+                                          grpc_byte_stream *bs, size_t max,
+                                          grpc_closure *on_complete) {
+  inproc_slice_byte_stream *stream = (inproc_slice_byte_stream *)bs;
+  return (stream->le->sb.count != 0);
+}
+
+static grpc_error *inproc_slice_byte_stream_pull(grpc_exec_ctx *exec_ctx,
+                                                 grpc_byte_stream *bs,
+                                                 grpc_slice *slice) {
+  inproc_slice_byte_stream *stream = (inproc_slice_byte_stream *)bs;
+  *slice = grpc_slice_buffer_take_first(&stream->le->sb);
+  return GRPC_ERROR_NONE;
+}
+
+static void inproc_slice_byte_stream_destroy(grpc_exec_ctx *exec_ctx,
+                                             grpc_byte_stream *bs) {
+  inproc_slice_byte_stream *stream = (inproc_slice_byte_stream *)bs;
+  sb_list_entry_destroy(exec_ctx, stream->le);
+}
+
+void inproc_slice_byte_stream_init(inproc_slice_byte_stream *s,
+                                   sb_list_entry *le) {
+  s->base.length = (uint32_t)le->sb.length;
+  s->base.flags = 0;
+  s->base.next = inproc_slice_byte_stream_next;
+  s->base.pull = inproc_slice_byte_stream_pull;
+  s->base.destroy = inproc_slice_byte_stream_destroy;
+  s->le = le;
+}
+
+static void ref_transport(inproc_transport *t) {
+  INPROC_LOG(GPR_DEBUG, "ref_transport %p", t);
+  gpr_ref(&t->refs);
+}
+
+static void really_destroy_transport(grpc_exec_ctx *exec_ctx,
+                                     inproc_transport *t) {
+  INPROC_LOG(GPR_DEBUG, "really_destroy_transport %p", t);
+  grpc_connectivity_state_destroy(exec_ctx, &t->connectivity);
+  if (gpr_unref(&t->mu->refs)) {
+    gpr_free(t->mu);
+  }
+  gpr_free(t);
+}
+
+static void unref_transport(grpc_exec_ctx *exec_ctx, inproc_transport *t) {
+  INPROC_LOG(GPR_DEBUG, "unref_transport %p", t);
+  if (gpr_unref(&t->refs)) {
+    really_destroy_transport(exec_ctx, t);
+  }
+}
+
+#ifndef NDEBUG
+#define STREAM_REF(refs, reason) grpc_stream_ref(refs, reason)
+#define STREAM_UNREF(e, refs, reason) grpc_stream_unref(e, refs, reason)
+#else
+#define STREAM_REF(refs, reason) grpc_stream_ref(refs)
+#define STREAM_UNREF(e, refs, reason) grpc_stream_unref(e, refs)
+#endif
+
+static void ref_stream(inproc_stream *s, const char *reason) {
+  INPROC_LOG(GPR_DEBUG, "ref_stream %p %s", s, reason);
+  STREAM_REF(s->refs, reason);
+}
+
+static void unref_stream(grpc_exec_ctx *exec_ctx, inproc_stream *s,
+                         const char *reason) {
+  INPROC_LOG(GPR_DEBUG, "unref_stream %p %s", s, reason);
+  STREAM_UNREF(exec_ctx, s->refs, reason);
+}
+
+static void really_destroy_stream(grpc_exec_ctx *exec_ctx, inproc_stream *s) {
+  INPROC_LOG(GPR_DEBUG, "really_destroy_stream %p", s);
+
+  slice_buffer_list_destroy(exec_ctx, &s->to_read_message);
+  slice_buffer_list_destroy(exec_ctx, &s->write_buffer_message);
+  GRPC_ERROR_UNREF(s->write_buffer_cancel_error);
+  GRPC_ERROR_UNREF(s->cancel_self_error);
+  GRPC_ERROR_UNREF(s->cancel_other_error);
+
+  unref_transport(exec_ctx, s->t);
+
+  if (s->closure_at_destroy) {
+    GRPC_CLOSURE_SCHED(exec_ctx, s->closure_at_destroy, GRPC_ERROR_NONE);
+  }
+}
+
+static void read_state_machine(grpc_exec_ctx *exec_ctx, void *arg,
+                               grpc_error *error);
+
+static void log_metadata(const grpc_metadata_batch *md_batch, bool is_client,
+                         bool is_initial) {
+  for (grpc_linked_mdelem *md = md_batch->list.head; md != NULL;
+       md = md->next) {
+    char *key = grpc_slice_to_c_string(GRPC_MDKEY(md->md));
+    char *value = grpc_slice_to_c_string(GRPC_MDVALUE(md->md));
+    gpr_log(GPR_INFO, "INPROC:%s:%s: %s: %s", is_initial ? "HDR" : "TRL",
+            is_client ? "CLI" : "SVR", key, value);
+    gpr_free(key);
+    gpr_free(value);
+  }
+}
+
+static grpc_error *fill_in_metadata(grpc_exec_ctx *exec_ctx, inproc_stream *s,
+                                    const grpc_metadata_batch *metadata,
+                                    uint32_t flags, grpc_metadata_batch *out_md,
+                                    uint32_t *outflags, bool *markfilled) {
+  if (GRPC_TRACER_ON(grpc_inproc_trace)) {
+    log_metadata(metadata, s->t->is_client, outflags != NULL);
+  }
+
+  if (outflags != NULL) {
+    *outflags = flags;
+  }
+  if (markfilled != NULL) {
+    *markfilled = true;
+  }
+  grpc_error *error = GRPC_ERROR_NONE;
+  for (grpc_linked_mdelem *elem = metadata->list.head;
+       (elem != NULL) && (error == GRPC_ERROR_NONE); elem = elem->next) {
+    grpc_linked_mdelem *nelem = gpr_arena_alloc(s->arena, sizeof(*nelem));
+    nelem->md = grpc_mdelem_from_slices(
+        exec_ctx, grpc_slice_intern(GRPC_MDKEY(elem->md)),
+        grpc_slice_intern(GRPC_MDVALUE(elem->md)));
+
+    error = grpc_metadata_batch_link_tail(exec_ctx, out_md, nelem);
+  }
+  return error;
+}
+
+static int init_stream(grpc_exec_ctx *exec_ctx, grpc_transport *gt,
+                       grpc_stream *gs, grpc_stream_refcount *refcount,
+                       const void *server_data, gpr_arena *arena) {
+  INPROC_LOG(GPR_DEBUG, "init_stream %p %p %p", gt, gs, server_data);
+  inproc_transport *t = (inproc_transport *)gt;
+  inproc_stream *s = (inproc_stream *)gs;
+  s->arena = arena;
+
+  s->refs = refcount;
+  // Ref this stream right now
+  ref_stream(s, "inproc_init_stream:init");
+
+  grpc_metadata_batch_init(&s->to_read_initial_md);
+  s->to_read_initial_md_flags = 0;
+  s->to_read_initial_md_filled = false;
+  grpc_metadata_batch_init(&s->to_read_trailing_md);
+  s->to_read_trailing_md_filled = false;
+  grpc_metadata_batch_init(&s->write_buffer_initial_md);
+  s->write_buffer_initial_md_flags = 0;
+  s->write_buffer_initial_md_filled = false;
+  grpc_metadata_batch_init(&s->write_buffer_trailing_md);
+  s->write_buffer_trailing_md_filled = false;
+  slice_buffer_list_init(&s->to_read_message);
+  slice_buffer_list_init(&s->write_buffer_message);
+  s->reads_needed = false;
+  s->read_closure_scheduled = false;
+  GRPC_CLOSURE_INIT(&s->read_closure, read_state_machine, s,
+                    grpc_schedule_on_exec_ctx);
+  s->t = t;
+  s->closure_at_destroy = NULL;
+  s->other_side_closed = false;
+
+  s->initial_md_sent = s->trailing_md_sent = s->initial_md_recvd =
+      s->trailing_md_recvd = false;
+
+  s->closed = false;
+
+  s->cancel_self_error = GRPC_ERROR_NONE;
+  s->cancel_other_error = GRPC_ERROR_NONE;
+  s->write_buffer_cancel_error = GRPC_ERROR_NONE;
+  s->deadline = gpr_inf_future(GPR_CLOCK_MONOTONIC);
+  s->write_buffer_deadline = gpr_inf_future(GPR_CLOCK_MONOTONIC);
+
+  s->stream_list_prev = NULL;
+  gpr_mu_lock(&t->mu->mu);
+  s->listed = true;
+  ref_stream(s, "inproc_init_stream:list");
+  s->stream_list_next = t->stream_list;
+  if (t->stream_list) {
+    t->stream_list->stream_list_prev = s;
+  }
+  t->stream_list = s;
+  gpr_mu_unlock(&t->mu->mu);
+
+  if (!server_data) {
+    ref_transport(t);
+    inproc_transport *st = t->other_side;
+    ref_transport(st);
+    s->other_side = NULL;  // will get filled in soon
+    // Pass the client-side stream address to the server-side for a ref
+    ref_stream(s, "inproc_init_stream:clt");  // ref it now on behalf of server
+                                              // side to avoid destruction
+    INPROC_LOG(GPR_DEBUG, "calling accept stream cb %p %p",
+               st->accept_stream_cb, st->accept_stream_data);
+    (*st->accept_stream_cb)(exec_ctx, st->accept_stream_data, &st->base,
+                            (void *)s);
+  } else {
+    // This is the server-side and is being called through accept_stream_cb
+    inproc_stream *cs = (inproc_stream *)server_data;
+    s->other_side = cs;
+    // Ref the server-side stream on behalf of the client now
+    ref_stream(s, "inproc_init_stream:srv");
+
+    // Now we are about to affect the other side, so lock the transport
+    // to make sure that it doesn't get destroyed
+    gpr_mu_lock(&s->t->mu->mu);
+    cs->other_side = s;
+    // Now transfer from the other side's write_buffer if any to the to_read
+    // buffer
+    if (cs->write_buffer_initial_md_filled) {
+      fill_in_metadata(exec_ctx, s, &cs->write_buffer_initial_md,
+                       cs->write_buffer_initial_md_flags,
+                       &s->to_read_initial_md, &s->to_read_initial_md_flags,
+                       &s->to_read_initial_md_filled);
+      s->deadline = gpr_time_min(s->deadline, cs->write_buffer_deadline);
+      grpc_metadata_batch_clear(exec_ctx, &cs->write_buffer_initial_md);
+      cs->write_buffer_initial_md_filled = false;
+    }
+    while (!slice_buffer_list_empty(&cs->write_buffer_message)) {
+      slice_buffer_list_append_entry(
+          &s->to_read_message,
+          slice_buffer_list_pophead(&cs->write_buffer_message));
+    }
+    if (cs->write_buffer_trailing_md_filled) {
+      fill_in_metadata(exec_ctx, s, &cs->write_buffer_trailing_md, 0,
+                       &s->to_read_trailing_md, NULL,
+                       &s->to_read_trailing_md_filled);
+      grpc_metadata_batch_clear(exec_ctx, &cs->write_buffer_trailing_md);
+      cs->write_buffer_trailing_md_filled = false;
+    }
+    if (cs->write_buffer_cancel_error != GRPC_ERROR_NONE) {
+      s->cancel_other_error = cs->write_buffer_cancel_error;
+      cs->write_buffer_cancel_error = GRPC_ERROR_NONE;
+    }
+
+    gpr_mu_unlock(&s->t->mu->mu);
+  }
+  return 0;  // return value is not important
+}
+
+static void close_stream_locked(grpc_exec_ctx *exec_ctx, inproc_stream *s) {
+  if (!s->closed) {
+    // Release the metadata that we would have written out
+    grpc_metadata_batch_destroy(exec_ctx, &s->write_buffer_initial_md);
+    grpc_metadata_batch_destroy(exec_ctx, &s->write_buffer_trailing_md);
+
+    if (s->listed) {
+      inproc_stream *p = s->stream_list_prev;
+      inproc_stream *n = s->stream_list_next;
+      if (p != NULL) {
+        p->stream_list_next = n;
+      } else {
+        s->t->stream_list = n;
+      }
+      if (n != NULL) {
+        n->stream_list_prev = p;
+      }
+      s->listed = false;
+      unref_stream(exec_ctx, s, "close_stream:list");
+    }
+    s->closed = true;
+    unref_stream(exec_ctx, s, "close_stream:closing");
+  }
+}
+
+// This function means that we are done talking/listening to the other side
+static void close_other_side_locked(grpc_exec_ctx *exec_ctx, inproc_stream *s,
+                                    const char *reason) {
+  if (s->other_side != NULL) {
+    // First release the metadata that came from the other side's arena
+    grpc_metadata_batch_destroy(exec_ctx, &s->to_read_initial_md);
+    grpc_metadata_batch_destroy(exec_ctx, &s->to_read_trailing_md);
+
+    unref_stream(exec_ctx, s->other_side, reason);
+    s->other_side_closed = true;
+    s->other_side = NULL;
+  } else if (!s->other_side_closed) {
+    s->write_buffer_other_side_closed = true;
+  }
+}
+
+static void fail_helper_locked(grpc_exec_ctx *exec_ctx, inproc_stream *s,
+                               grpc_error *error) {
+  INPROC_LOG(GPR_DEBUG, "read_state_machine %p fail_helper", s);
+  // If we're failing this side, we need to make sure that
+  // we also send or have already sent trailing metadata
+  if (!s->trailing_md_sent) {
+    // Send trailing md to the other side indicating cancellation
+    s->trailing_md_sent = true;
+
+    grpc_metadata_batch fake_md;
+    grpc_metadata_batch_init(&fake_md);
+
+    inproc_stream *other = s->other_side;
+    grpc_metadata_batch *dest = (other == NULL) ? &s->write_buffer_trailing_md
+                                                : &other->to_read_trailing_md;
+    bool *destfilled = (other == NULL) ? &s->write_buffer_trailing_md_filled
+                                       : &other->to_read_trailing_md_filled;
+    fill_in_metadata(exec_ctx, s, &fake_md, 0, dest, NULL, destfilled);
+    grpc_metadata_batch_destroy(exec_ctx, &fake_md);
+
+    if (other != NULL) {
+      if (other->cancel_other_error == GRPC_ERROR_NONE) {
+        other->cancel_other_error = GRPC_ERROR_REF(error);
+      }
+      if (other->reads_needed) {
+        if (!other->read_closure_scheduled) {
+          GRPC_CLOSURE_SCHED(exec_ctx, &other->read_closure,
+                             GRPC_ERROR_REF(error));
+          other->read_closure_scheduled = true;
+        }
+        other->reads_needed = false;
+      }
+    } else if (s->write_buffer_cancel_error == GRPC_ERROR_NONE) {
+      s->write_buffer_cancel_error = GRPC_ERROR_REF(error);
+    }
+  }
+  if (s->recv_initial_md_op) {
+    grpc_error *err;
+    if (!s->t->is_client) {
+      // If this is a server, provide initial metadata with a path and authority
+      // since it expects that as well as no error yet
+      grpc_metadata_batch fake_md;
+      grpc_metadata_batch_init(&fake_md);
+      grpc_linked_mdelem *path_md = gpr_arena_alloc(s->arena, sizeof(*path_md));
+      path_md->md =
+          grpc_mdelem_from_slices(exec_ctx, g_fake_path_key, g_fake_path_value);
+      GPR_ASSERT(grpc_metadata_batch_link_tail(exec_ctx, &fake_md, path_md) ==
+                 GRPC_ERROR_NONE);
+      grpc_linked_mdelem *auth_md = gpr_arena_alloc(s->arena, sizeof(*auth_md));
+      auth_md->md =
+          grpc_mdelem_from_slices(exec_ctx, g_fake_auth_key, g_fake_auth_value);
+      GPR_ASSERT(grpc_metadata_batch_link_tail(exec_ctx, &fake_md, auth_md) ==
+                 GRPC_ERROR_NONE);
+
+      fill_in_metadata(
+          exec_ctx, s, &fake_md, 0,
+          s->recv_initial_md_op->payload->recv_initial_metadata
+              .recv_initial_metadata,
+          s->recv_initial_md_op->payload->recv_initial_metadata.recv_flags,
+          NULL);
+      grpc_metadata_batch_destroy(exec_ctx, &fake_md);
+      err = GRPC_ERROR_NONE;
+    } else {
+      err = GRPC_ERROR_REF(error);
+    }
+    INPROC_LOG(GPR_DEBUG,
+               "fail_helper %p scheduling initial-metadata-ready %p %p", s,
+               error, err);
+    GRPC_CLOSURE_SCHED(exec_ctx,
+                       s->recv_initial_md_op->payload->recv_initial_metadata
+                           .recv_initial_metadata_ready,
+                       err);
+    // Last use of err so no need to REF and then UNREF it
+
+    if ((s->recv_initial_md_op != s->recv_message_op) &&
+        (s->recv_initial_md_op != s->recv_trailing_md_op)) {
+      INPROC_LOG(GPR_DEBUG,
+                 "fail_helper %p scheduling initial-metadata-on-complete %p",
+                 error, s);
+      GRPC_CLOSURE_SCHED(exec_ctx, s->recv_initial_md_op->on_complete,
+                         GRPC_ERROR_REF(error));
+    }
+    s->recv_initial_md_op = NULL;
+  }
+  if (s->recv_message_op) {
+    INPROC_LOG(GPR_DEBUG, "fail_helper %p scheduling message-ready %p", s,
+               error);
+    GRPC_CLOSURE_SCHED(
+        exec_ctx, s->recv_message_op->payload->recv_message.recv_message_ready,
+        GRPC_ERROR_REF(error));
+    if (s->recv_message_op != s->recv_trailing_md_op) {
+      INPROC_LOG(GPR_DEBUG, "fail_helper %p scheduling message-on-complete %p",
+                 s, error);
+      GRPC_CLOSURE_SCHED(exec_ctx, s->recv_message_op->on_complete,
+                         GRPC_ERROR_REF(error));
+    }
+    s->recv_message_op = NULL;
+  }
+  if (s->recv_trailing_md_op) {
+    INPROC_LOG(GPR_DEBUG,
+               "fail_helper %p scheduling trailing-md-on-complete %p", s,
+               error);
+    GRPC_CLOSURE_SCHED(exec_ctx, s->recv_trailing_md_op->on_complete,
+                       GRPC_ERROR_REF(error));
+    s->recv_trailing_md_op = NULL;
+  }
+  close_other_side_locked(exec_ctx, s, "fail_helper:other_side");
+  close_stream_locked(exec_ctx, s);
+
+  GRPC_ERROR_UNREF(error);
+}
+
+static void read_state_machine(grpc_exec_ctx *exec_ctx, void *arg,
+                               grpc_error *error) {
+  // This function gets called when we have contents in the unprocessed reads
+  // Get what we want based on our ops wanted
+  // Schedule our appropriate closures
+  // and then return to reads_needed state if still needed
+
+  // Since this is a closure directly invoked by the combiner, it should not
+  // unref the error parameter explicitly; the combiner will do that implicitly
+  grpc_error *new_err = GRPC_ERROR_NONE;
+
+  bool needs_close = false;
+
+  INPROC_LOG(GPR_DEBUG, "read_state_machine %p", arg);
+  inproc_stream *s = (inproc_stream *)arg;
+  gpr_mu *mu = &s->t->mu->mu;  // keep aside in case s gets closed
+  gpr_mu_lock(mu);
+  s->read_closure_scheduled = false;
+  // cancellation takes precedence
+  if (s->cancel_self_error != GRPC_ERROR_NONE) {
+    fail_helper_locked(exec_ctx, s, GRPC_ERROR_REF(s->cancel_self_error));
+    goto done;
+  } else if (s->cancel_other_error != GRPC_ERROR_NONE) {
+    fail_helper_locked(exec_ctx, s, GRPC_ERROR_REF(s->cancel_other_error));
+    goto done;
+  } else if (error != GRPC_ERROR_NONE) {
+    fail_helper_locked(exec_ctx, s, GRPC_ERROR_REF(error));
+    goto done;
+  }
+
+  if (s->recv_initial_md_op) {
+    if (!s->to_read_initial_md_filled) {
+      // We entered the state machine on some other kind of read even though
+      // we still haven't satisfied initial md . That's an error.
+      new_err =
+          GRPC_ERROR_CREATE_FROM_STATIC_STRING("Unexpected frame sequencing");
+      INPROC_LOG(GPR_DEBUG,
+                 "read_state_machine %p scheduling on_complete errors for no "
+                 "initial md %p",
+                 s, new_err);
+      fail_helper_locked(exec_ctx, s, GRPC_ERROR_REF(new_err));
+      goto done;
+    } else if (s->initial_md_recvd) {
+      new_err =
+          GRPC_ERROR_CREATE_FROM_STATIC_STRING("Already recvd initial md");
+      INPROC_LOG(
+          GPR_DEBUG,
+          "read_state_machine %p scheduling on_complete errors for already "
+          "recvd initial md %p",
+          s, new_err);
+      fail_helper_locked(exec_ctx, s, GRPC_ERROR_REF(new_err));
+      goto done;
+    }
+
+    s->initial_md_recvd = true;
+    new_err = fill_in_metadata(
+        exec_ctx, s, &s->to_read_initial_md, s->to_read_initial_md_flags,
+        s->recv_initial_md_op->payload->recv_initial_metadata
+            .recv_initial_metadata,
+        s->recv_initial_md_op->payload->recv_initial_metadata.recv_flags, NULL);
+    s->recv_initial_md_op->payload->recv_initial_metadata.recv_initial_metadata
+        ->deadline = s->deadline;
+    grpc_metadata_batch_clear(exec_ctx, &s->to_read_initial_md);
+    s->to_read_initial_md_filled = false;
+    INPROC_LOG(GPR_DEBUG,
+               "read_state_machine %p scheduling initial-metadata-ready %p", s,
+               new_err);
+    GRPC_CLOSURE_SCHED(exec_ctx,
+                       s->recv_initial_md_op->payload->recv_initial_metadata
+                           .recv_initial_metadata_ready,
+                       GRPC_ERROR_REF(new_err));
+    if ((s->recv_initial_md_op != s->recv_message_op) &&
+        (s->recv_initial_md_op != s->recv_trailing_md_op)) {
+      INPROC_LOG(
+          GPR_DEBUG,
+          "read_state_machine %p scheduling initial-metadata-on-complete %p", s,
+          new_err);
+      GRPC_CLOSURE_SCHED(exec_ctx, s->recv_initial_md_op->on_complete,
+                         GRPC_ERROR_REF(new_err));
+    }
+    s->recv_initial_md_op = NULL;
+
+    if (new_err != GRPC_ERROR_NONE) {
+      INPROC_LOG(GPR_DEBUG,
+                 "read_state_machine %p scheduling on_complete errors2 %p", s,
+                 new_err);
+      fail_helper_locked(exec_ctx, s, GRPC_ERROR_REF(new_err));
+      goto done;
+    }
+  }
+  if (s->to_read_initial_md_filled) {
+    new_err = GRPC_ERROR_CREATE_FROM_STATIC_STRING("Unexpected recv frame");
+    fail_helper_locked(exec_ctx, s, GRPC_ERROR_REF(new_err));
+    goto done;
+  }
+  if (!slice_buffer_list_empty(&s->to_read_message) && s->recv_message_op) {
+    inproc_slice_byte_stream_init(
+        &s->recv_message_stream,
+        slice_buffer_list_pophead(&s->to_read_message));
+    *s->recv_message_op->payload->recv_message.recv_message =
+        &s->recv_message_stream.base;
+    INPROC_LOG(GPR_DEBUG, "read_state_machine %p scheduling message-ready", s);
+    GRPC_CLOSURE_SCHED(
+        exec_ctx, s->recv_message_op->payload->recv_message.recv_message_ready,
+        GRPC_ERROR_NONE);
+    if (s->recv_message_op != s->recv_trailing_md_op) {
+      INPROC_LOG(GPR_DEBUG,
+                 "read_state_machine %p scheduling message-on-complete %p", s,
+                 new_err);
+      GRPC_CLOSURE_SCHED(exec_ctx, s->recv_message_op->on_complete,
+                         GRPC_ERROR_REF(new_err));
+    }
+    s->recv_message_op = NULL;
+  }
+  if (s->to_read_trailing_md_filled) {
+    if (s->trailing_md_recvd) {
+      new_err =
+          GRPC_ERROR_CREATE_FROM_STATIC_STRING("Already recvd trailing md");
+      INPROC_LOG(
+          GPR_DEBUG,
+          "read_state_machine %p scheduling on_complete errors for already "
+          "recvd trailing md %p",
+          s, new_err);
+      fail_helper_locked(exec_ctx, s, GRPC_ERROR_REF(new_err));
+      goto done;
+    }
+    if (s->recv_message_op != NULL) {
+      // This message needs to be wrapped up because it will never be
+      // satisfied
+      INPROC_LOG(GPR_DEBUG, "read_state_machine %p scheduling message-ready",
+                 s);
+      GRPC_CLOSURE_SCHED(
+          exec_ctx,
+          s->recv_message_op->payload->recv_message.recv_message_ready,
+          GRPC_ERROR_NONE);
+      if (s->recv_message_op != s->recv_trailing_md_op) {
+        INPROC_LOG(GPR_DEBUG,
+                   "read_state_machine %p scheduling message-on-complete %p", s,
+                   new_err);
+        GRPC_CLOSURE_SCHED(exec_ctx, s->recv_message_op->on_complete,
+                           GRPC_ERROR_REF(new_err));
+      }
+      s->recv_message_op = NULL;
+    }
+    if (s->recv_trailing_md_op != NULL) {
+      // We wanted trailing metadata and we got it
+      s->trailing_md_recvd = true;
+      new_err =
+          fill_in_metadata(exec_ctx, s, &s->to_read_trailing_md, 0,
+                           s->recv_trailing_md_op->payload
+                               ->recv_trailing_metadata.recv_trailing_metadata,
+                           NULL, NULL);
+      grpc_metadata_batch_clear(exec_ctx, &s->to_read_trailing_md);
+      s->to_read_trailing_md_filled = false;
+
+      // We should schedule the recv_trailing_md_op completion if
+      // 1. this stream is the client-side
+      // 2. this stream is the server-side AND has already sent its trailing md
+      //    (If the server hasn't already sent its trailing md, it doesn't have
+      //     a final status, so don't mark this op complete)
+      if (s->t->is_client || s->trailing_md_sent) {
+        INPROC_LOG(
+            GPR_DEBUG,
+            "read_state_machine %p scheduling trailing-md-on-complete %p", s,
+            new_err);
+        GRPC_CLOSURE_SCHED(exec_ctx, s->recv_trailing_md_op->on_complete,
+                           GRPC_ERROR_REF(new_err));
+        s->recv_trailing_md_op = NULL;
+        needs_close = true;
+      } else {
+        INPROC_LOG(GPR_DEBUG,
+                   "read_state_machine %p server needs to delay handling "
+                   "trailing-md-on-complete %p",
+                   s, new_err);
+      }
+    } else {
+      INPROC_LOG(
+          GPR_DEBUG,
+          "read_state_machine %p has trailing md but not yet waiting for it",
+          s);
+    }
+  }
+  if (s->trailing_md_recvd && s->recv_message_op) {
+    // No further message will come on this stream, so finish off the
+    // recv_message_op
+    INPROC_LOG(GPR_DEBUG, "read_state_machine %p scheduling message-ready", s);
+    GRPC_CLOSURE_SCHED(
+        exec_ctx, s->recv_message_op->payload->recv_message.recv_message_ready,
+        GRPC_ERROR_NONE);
+    if (s->recv_message_op != s->recv_trailing_md_op) {
+      INPROC_LOG(GPR_DEBUG,
+                 "read_state_machine %p scheduling message-on-complete %p", s,
+                 new_err);
+      GRPC_CLOSURE_SCHED(exec_ctx, s->recv_message_op->on_complete,
+                         GRPC_ERROR_REF(new_err));
+    }
+    s->recv_message_op = NULL;
+  }
+  if (s->recv_message_op || s->recv_trailing_md_op) {
+    // Didn't get the item we wanted so we still need to get
+    // rescheduled
+    INPROC_LOG(GPR_DEBUG, "read_state_machine %p still needs closure %p %p", s,
+               s->recv_message_op, s->recv_trailing_md_op);
+    s->reads_needed = true;
+  }
+done:
+  if (needs_close) {
+    close_other_side_locked(exec_ctx, s, "read_state_machine");
+    close_stream_locked(exec_ctx, s);
+  }
+  gpr_mu_unlock(mu);
+  GRPC_ERROR_UNREF(new_err);
+}
+
+static grpc_closure do_nothing_closure;
+
+static bool cancel_stream_locked(grpc_exec_ctx *exec_ctx, inproc_stream *s,
+                                 grpc_error *error) {
+  bool ret = false;  // was the cancel accepted
+  INPROC_LOG(GPR_DEBUG, "cancel_stream %p with %s", s,
+             grpc_error_string(error));
+  if (s->cancel_self_error == GRPC_ERROR_NONE) {
+    ret = true;
+    s->cancel_self_error = GRPC_ERROR_REF(error);
+    if (s->reads_needed) {
+      if (!s->read_closure_scheduled) {
+        GRPC_CLOSURE_SCHED(exec_ctx, &s->read_closure,
+                           GRPC_ERROR_REF(s->cancel_self_error));
+        s->read_closure_scheduled = true;
+      }
+      s->reads_needed = false;
+    }
+    // Send trailing md to the other side indicating cancellation, even if we
+    // already have
+    s->trailing_md_sent = true;
+
+    grpc_metadata_batch cancel_md;
+    grpc_metadata_batch_init(&cancel_md);
+
+    inproc_stream *other = s->other_side;
+    grpc_metadata_batch *dest = (other == NULL) ? &s->write_buffer_trailing_md
+                                                : &other->to_read_trailing_md;
+    bool *destfilled = (other == NULL) ? &s->write_buffer_trailing_md_filled
+                                       : &other->to_read_trailing_md_filled;
+    fill_in_metadata(exec_ctx, s, &cancel_md, 0, dest, NULL, destfilled);
+    grpc_metadata_batch_destroy(exec_ctx, &cancel_md);
+
+    if (other != NULL) {
+      if (other->cancel_other_error == GRPC_ERROR_NONE) {
+        other->cancel_other_error = GRPC_ERROR_REF(s->cancel_self_error);
+      }
+      if (other->reads_needed) {
+        if (!other->read_closure_scheduled) {
+          GRPC_CLOSURE_SCHED(exec_ctx, &other->read_closure,
+                             GRPC_ERROR_REF(other->cancel_other_error));
+          other->read_closure_scheduled = true;
+        }
+        other->reads_needed = false;
+      }
+    } else if (s->write_buffer_cancel_error == GRPC_ERROR_NONE) {
+      s->write_buffer_cancel_error = GRPC_ERROR_REF(s->cancel_self_error);
+    }
+
+    // if we are a server and already received trailing md but
+    // couldn't complete that because we hadn't yet sent out trailing
+    // md, now's the chance
+    if (!s->t->is_client && s->trailing_md_recvd && s->recv_trailing_md_op) {
+      INPROC_LOG(GPR_DEBUG,
+                 "cancel_stream %p scheduling trailing-md-on-complete %p", s,
+                 s->cancel_self_error);
+      GRPC_CLOSURE_SCHED(exec_ctx, s->recv_trailing_md_op->on_complete,
+                         GRPC_ERROR_REF(s->cancel_self_error));
+      s->recv_trailing_md_op = NULL;
+    }
+  }
+
+  close_other_side_locked(exec_ctx, s, "cancel_stream:other_side");
+  close_stream_locked(exec_ctx, s);
+
+  GRPC_ERROR_UNREF(error);
+  return ret;
+}
+
+static void perform_stream_op(grpc_exec_ctx *exec_ctx, grpc_transport *gt,
+                              grpc_stream *gs,
+                              grpc_transport_stream_op_batch *op) {
+  INPROC_LOG(GPR_DEBUG, "perform_stream_op %p %p %p", gt, gs, op);
+  inproc_stream *s = (inproc_stream *)gs;
+  gpr_mu *mu = &s->t->mu->mu;  // save aside in case s gets closed
+  gpr_mu_lock(mu);
+
+  if (GRPC_TRACER_ON(grpc_inproc_trace)) {
+    if (op->send_initial_metadata) {
+      log_metadata(op->payload->send_initial_metadata.send_initial_metadata,
+                   s->t->is_client, true);
+    }
+    if (op->send_trailing_metadata) {
+      log_metadata(op->payload->send_trailing_metadata.send_trailing_metadata,
+                   s->t->is_client, false);
+    }
+  }
+  grpc_error *error = GRPC_ERROR_NONE;
+  grpc_closure *on_complete = op->on_complete;
+  if (on_complete == NULL) {
+    on_complete = &do_nothing_closure;
+  }
+
+  if (op->cancel_stream) {
+    // Call cancel_stream_locked without ref'ing the cancel_error because
+    // this function is responsible to make sure that that field gets unref'ed
+    cancel_stream_locked(exec_ctx, s, op->payload->cancel_stream.cancel_error);
+    // this op can complete without an error
+  } else if (s->cancel_self_error != GRPC_ERROR_NONE) {
+    // already self-canceled so still give it an error
+    error = GRPC_ERROR_REF(s->cancel_self_error);
+  } else {
+    INPROC_LOG(GPR_DEBUG, "perform_stream_op %p%s%s%s%s%s%s", s,
+               op->send_initial_metadata ? " send_initial_metadata" : "",
+               op->send_message ? " send_message" : "",
+               op->send_trailing_metadata ? " send_trailing_metadata" : "",
+               op->recv_initial_metadata ? " recv_initial_metadata" : "",
+               op->recv_message ? " recv_message" : "",
+               op->recv_trailing_metadata ? " recv_trailing_metadata" : "");
+  }
+
+  bool needs_close = false;
+
+  if (error == GRPC_ERROR_NONE &&
+      (op->send_initial_metadata || op->send_message ||
+       op->send_trailing_metadata)) {
+    inproc_stream *other = s->other_side;
+    if (s->t->is_closed) {
+      error = GRPC_ERROR_CREATE_FROM_STATIC_STRING("Endpoint already shutdown");
+    }
+    if (error == GRPC_ERROR_NONE && op->send_initial_metadata) {
+      grpc_metadata_batch *dest = (other == NULL) ? &s->write_buffer_initial_md
+                                                  : &other->to_read_initial_md;
+      uint32_t *destflags = (other == NULL) ? &s->write_buffer_initial_md_flags
+                                            : &other->to_read_initial_md_flags;
+      bool *destfilled = (other == NULL) ? &s->write_buffer_initial_md_filled
+                                         : &other->to_read_initial_md_filled;
+      if (*destfilled || s->initial_md_sent) {
+        // The buffer is already in use; that's an error!
+        INPROC_LOG(GPR_DEBUG, "Extra initial metadata %p", s);
+        error = GRPC_ERROR_CREATE_FROM_STATIC_STRING("Extra initial metadata");
+      } else {
+        if (!other->closed) {
+          fill_in_metadata(
+              exec_ctx, s,
+              op->payload->send_initial_metadata.send_initial_metadata,
+              op->payload->send_initial_metadata.send_initial_metadata_flags,
+              dest, destflags, destfilled);
+        }
+        if (s->t->is_client) {
+          gpr_timespec *dl =
+              (other == NULL) ? &s->write_buffer_deadline : &other->deadline;
+          *dl = gpr_time_min(*dl, op->payload->send_initial_metadata
+                                      .send_initial_metadata->deadline);
+          s->initial_md_sent = true;
+        }
+      }
+    }
+    if (error == GRPC_ERROR_NONE && op->send_message) {
+      size_t remaining = op->payload->send_message.send_message->length;
+      grpc_slice_buffer *dest = slice_buffer_list_append(
+          (other == NULL) ? &s->write_buffer_message : &other->to_read_message);
+      do {
+        grpc_slice message_slice;
+        grpc_closure unused;
+        GPR_ASSERT(grpc_byte_stream_next(exec_ctx,
+                                         op->payload->send_message.send_message,
+                                         SIZE_MAX, &unused));
+        grpc_byte_stream_pull(exec_ctx, op->payload->send_message.send_message,
+                              &message_slice);
+        remaining -= GRPC_SLICE_LENGTH(message_slice);
+        grpc_slice_buffer_add(dest, message_slice);
+      } while (remaining != 0);
+    }
+    if (error == GRPC_ERROR_NONE && op->send_trailing_metadata) {
+      grpc_metadata_batch *dest = (other == NULL) ? &s->write_buffer_trailing_md
+                                                  : &other->to_read_trailing_md;
+      bool *destfilled = (other == NULL) ? &s->write_buffer_trailing_md_filled
+                                         : &other->to_read_trailing_md_filled;
+      if (*destfilled || s->trailing_md_sent) {
+        // The buffer is already in use; that's an error!
+        INPROC_LOG(GPR_DEBUG, "Extra trailing metadata %p", s);
+        error = GRPC_ERROR_CREATE_FROM_STATIC_STRING("Extra trailing metadata");
+      } else {
+        if (!other->closed) {
+          fill_in_metadata(
+              exec_ctx, s,
+              op->payload->send_trailing_metadata.send_trailing_metadata, 0,
+              dest, NULL, destfilled);
+        }
+        s->trailing_md_sent = true;
+        if (!s->t->is_client && s->trailing_md_recvd &&
+            s->recv_trailing_md_op) {
+          INPROC_LOG(GPR_DEBUG,
+                     "perform_stream_op %p scheduling trailing-md-on-complete",
+                     s);
+          GRPC_CLOSURE_SCHED(exec_ctx, s->recv_trailing_md_op->on_complete,
+                             GRPC_ERROR_NONE);
+          s->recv_trailing_md_op = NULL;
+          needs_close = true;
+        }
+      }
+    }
+    if (other != NULL && other->reads_needed) {
+      if (!other->read_closure_scheduled) {
+        GRPC_CLOSURE_SCHED(exec_ctx, &other->read_closure, error);
+        other->read_closure_scheduled = true;
+      }
+      other->reads_needed = false;
+    }
+  }
+  if (error == GRPC_ERROR_NONE &&
+      (op->recv_initial_metadata || op->recv_message ||
+       op->recv_trailing_metadata)) {
+    // If there are any reads, mark it so that the read closure will react to
+    // them
+    if (op->recv_initial_metadata) {
+      s->recv_initial_md_op = op;
+    }
+    if (op->recv_message) {
+      s->recv_message_op = op;
+    }
+    if (op->recv_trailing_metadata) {
+      s->recv_trailing_md_op = op;
+    }
+
+    // We want to initiate the closure if:
+    // 1. There is initial metadata and something ready to take that
+    // 2. There is a message and something ready to take it
+    // 3. There is trailing metadata, even if nothing specifically wants
+    //    that because that can shut down the message as well
+    if ((s->to_read_initial_md_filled && op->recv_initial_metadata) ||
+        ((!slice_buffer_list_empty(&s->to_read_message) ||
+          s->trailing_md_recvd) &&
+         op->recv_message) ||
+        (s->to_read_trailing_md_filled)) {
+      if (!s->read_closure_scheduled) {
+        GRPC_CLOSURE_SCHED(exec_ctx, &s->read_closure, GRPC_ERROR_NONE);
+        s->read_closure_scheduled = true;
+      }
+    } else {
+      s->reads_needed = true;
+    }
+  } else {
+    if (error != GRPC_ERROR_NONE) {
+      // Schedule op's read closures that we didn't push to read state machine
+      if (op->recv_initial_metadata) {
+        INPROC_LOG(
+            GPR_DEBUG,
+            "perform_stream_op error %p scheduling initial-metadata-ready %p",
+            s, error);
+        GRPC_CLOSURE_SCHED(
+            exec_ctx,
+            op->payload->recv_initial_metadata.recv_initial_metadata_ready,
+            GRPC_ERROR_REF(error));
+      }
+      if (op->recv_message) {
+        INPROC_LOG(
+            GPR_DEBUG,
+            "perform_stream_op error %p scheduling recv message-ready %p", s,
+            error);
+        GRPC_CLOSURE_SCHED(exec_ctx,
+                           op->payload->recv_message.recv_message_ready,
+                           GRPC_ERROR_REF(error));
+      }
+    }
+    INPROC_LOG(GPR_DEBUG, "perform_stream_op %p scheduling on_complete %p", s,
+               error);
+    GRPC_CLOSURE_SCHED(exec_ctx, on_complete, GRPC_ERROR_REF(error));
+  }
+  if (needs_close) {
+    close_other_side_locked(exec_ctx, s, "perform_stream_op:other_side");
+    close_stream_locked(exec_ctx, s);
+  }
+  gpr_mu_unlock(mu);
+  GRPC_ERROR_UNREF(error);
+}
+
+static void close_transport_locked(grpc_exec_ctx *exec_ctx,
+                                   inproc_transport *t) {
+  INPROC_LOG(GPR_DEBUG, "close_transport %p %d", t, t->is_closed);
+  grpc_connectivity_state_set(
+      exec_ctx, &t->connectivity, GRPC_CHANNEL_SHUTDOWN,
+      GRPC_ERROR_CREATE_FROM_STATIC_STRING("Closing transport."),
+      "close transport");
+  if (!t->is_closed) {
+    t->is_closed = true;
+    /* Also end all streams on this transport */
+    while (t->stream_list != NULL) {
+      // cancel_stream_locked also adjusts stream list
+      cancel_stream_locked(
+          exec_ctx, t->stream_list,
+          grpc_error_set_int(
+              GRPC_ERROR_CREATE_FROM_STATIC_STRING("Transport closed"),
+              GRPC_ERROR_INT_GRPC_STATUS, GRPC_STATUS_UNAVAILABLE));
+    }
+  }
+}
+
+static void perform_transport_op(grpc_exec_ctx *exec_ctx, grpc_transport *gt,
+                                 grpc_transport_op *op) {
+  inproc_transport *t = (inproc_transport *)gt;
+  INPROC_LOG(GPR_DEBUG, "perform_transport_op %p %p", t, op);
+  gpr_mu_lock(&t->mu->mu);
+  if (op->on_connectivity_state_change) {
+    grpc_connectivity_state_notify_on_state_change(
+        exec_ctx, &t->connectivity, op->connectivity_state,
+        op->on_connectivity_state_change);
+  }
+  if (op->set_accept_stream) {
+    t->accept_stream_cb = op->set_accept_stream_fn;
+    t->accept_stream_data = op->set_accept_stream_user_data;
+  }
+  if (op->on_consumed) {
+    GRPC_CLOSURE_SCHED(exec_ctx, op->on_consumed, GRPC_ERROR_NONE);
+  }
+
+  bool do_close = false;
+  if (op->goaway_error != GRPC_ERROR_NONE) {
+    do_close = true;
+    GRPC_ERROR_UNREF(op->goaway_error);
+  }
+  if (op->disconnect_with_error != GRPC_ERROR_NONE) {
+    do_close = true;
+    GRPC_ERROR_UNREF(op->disconnect_with_error);
+  }
+
+  if (do_close) {
+    close_transport_locked(exec_ctx, t);
+  }
+  gpr_mu_unlock(&t->mu->mu);
+}
+
+static void destroy_stream(grpc_exec_ctx *exec_ctx, grpc_transport *gt,
+                           grpc_stream *gs,
+                           grpc_closure *then_schedule_closure) {
+  INPROC_LOG(GPR_DEBUG, "destroy_stream %p %p", gs, then_schedule_closure);
+  inproc_stream *s = (inproc_stream *)gs;
+  s->closure_at_destroy = then_schedule_closure;
+  really_destroy_stream(exec_ctx, s);
+}
+
+static void destroy_transport(grpc_exec_ctx *exec_ctx, grpc_transport *gt) {
+  inproc_transport *t = (inproc_transport *)gt;
+  INPROC_LOG(GPR_DEBUG, "destroy_transport %p", t);
+  gpr_mu_lock(&t->mu->mu);
+  close_transport_locked(exec_ctx, t);
+  gpr_mu_unlock(&t->mu->mu);
+  unref_transport(exec_ctx, t->other_side);
+  unref_transport(exec_ctx, t);
+}
+
+/*******************************************************************************
+ * Main inproc transport functions
+ */
+static void inproc_transports_create(grpc_exec_ctx *exec_ctx,
+                                     grpc_transport **server_transport,
+                                     const grpc_channel_args *server_args,
+                                     grpc_transport **client_transport,
+                                     const grpc_channel_args *client_args) {
+  INPROC_LOG(GPR_DEBUG, "inproc_transports_create");
+  inproc_transport *st = gpr_zalloc(sizeof(*st));
+  inproc_transport *ct = gpr_zalloc(sizeof(*ct));
+  // Share one lock between both sides since both sides get affected
+  st->mu = ct->mu = gpr_malloc(sizeof(*st->mu));
+  gpr_mu_init(&st->mu->mu);
+  gpr_ref_init(&st->mu->refs, 2);
+  st->base.vtable = &inproc_vtable;
+  ct->base.vtable = &inproc_vtable;
+  // Start each side of transport with 2 refs since they each have a ref
+  // to the other
+  gpr_ref_init(&st->refs, 2);
+  gpr_ref_init(&ct->refs, 2);
+  st->is_client = false;
+  ct->is_client = true;
+  grpc_connectivity_state_init(&st->connectivity, GRPC_CHANNEL_READY,
+                               "inproc_server");
+  grpc_connectivity_state_init(&ct->connectivity, GRPC_CHANNEL_READY,
+                               "inproc_client");
+  st->other_side = ct;
+  ct->other_side = st;
+  st->stream_list = NULL;
+  ct->stream_list = NULL;
+  *server_transport = (grpc_transport *)st;
+  *client_transport = (grpc_transport *)ct;
+}
+
+grpc_channel *grpc_inproc_channel_create(grpc_server *server,
+                                         grpc_channel_args *args,
+                                         void *reserved) {
+  GRPC_API_TRACE("grpc_inproc_channel_create(server=%p, args=%p)", 2,
+                 (server, args));
+
+  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
+
+  const grpc_channel_args *server_args = grpc_server_get_channel_args(server);
+
+  // Add a default authority channel argument for the client
+
+  grpc_arg default_authority_arg;
+  default_authority_arg.type = GRPC_ARG_STRING;
+  default_authority_arg.key = GRPC_ARG_DEFAULT_AUTHORITY;
+  default_authority_arg.value.string = "inproc.authority";
+  grpc_channel_args *client_args =
+      grpc_channel_args_copy_and_add(args, &default_authority_arg, 1);
+
+  grpc_transport *server_transport;
+  grpc_transport *client_transport;
+  inproc_transports_create(&exec_ctx, &server_transport, server_args,
+                           &client_transport, client_args);
+
+  grpc_server_setup_transport(&exec_ctx, server, server_transport, NULL,
+                              server_args);
+  grpc_channel *channel =
+      grpc_channel_create(&exec_ctx, "inproc", client_args,
+                          GRPC_CLIENT_DIRECT_CHANNEL, client_transport);
+
+  // Free up created channel args
+  grpc_channel_args_destroy(&exec_ctx, client_args);
+
+  // Now finish scheduled operations
+  grpc_exec_ctx_finish(&exec_ctx);
+
+  return channel;
+}
+
+/*******************************************************************************
+ * INTEGRATION GLUE
+ */
+
+static void set_pollset(grpc_exec_ctx *exec_ctx, grpc_transport *gt,
+                        grpc_stream *gs, grpc_pollset *pollset) {
+  // Nothing to do here
+}
+
+static void set_pollset_set(grpc_exec_ctx *exec_ctx, grpc_transport *gt,
+                            grpc_stream *gs, grpc_pollset_set *pollset_set) {
+  // Nothing to do here
+}
+
+static char *get_peer(grpc_exec_ctx *exec_ctx, grpc_transport *t) {
+  return gpr_strdup("inproc");
+}
+
+static grpc_endpoint *get_endpoint(grpc_exec_ctx *exec_ctx, grpc_transport *t) {
+  return NULL;
+}
+
+static const grpc_transport_vtable inproc_vtable = {
+    sizeof(inproc_stream), "inproc",
+    init_stream,           set_pollset,
+    set_pollset_set,       perform_stream_op,
+    perform_transport_op,  destroy_stream,
+    destroy_transport,     get_peer,
+    get_endpoint};
+
+/*******************************************************************************
+ * GLOBAL INIT AND DESTROY
+ */
+static void do_nothing(grpc_exec_ctx *exec_ctx, void *arg, grpc_error *error) {}
+
+void grpc_inproc_transport_init(void) {
+  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
+  GRPC_CLOSURE_INIT(&do_nothing_closure, do_nothing, NULL,
+                    grpc_schedule_on_exec_ctx);
+  g_empty_slice = grpc_slice_from_static_buffer(NULL, 0);
+
+  grpc_slice key_tmp = grpc_slice_from_static_string(":path");
+  g_fake_path_key = grpc_slice_intern(key_tmp);
+  grpc_slice_unref_internal(&exec_ctx, key_tmp);
+
+  g_fake_path_value = grpc_slice_from_static_string("/");
+
+  grpc_slice auth_tmp = grpc_slice_from_static_string(":authority");
+  g_fake_auth_key = grpc_slice_intern(auth_tmp);
+  grpc_slice_unref_internal(&exec_ctx, auth_tmp);
+
+  g_fake_auth_value = grpc_slice_from_static_string("inproc-fail");
+  grpc_exec_ctx_finish(&exec_ctx);
+}
+
+void grpc_inproc_transport_shutdown(void) {
+  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
+  grpc_slice_unref_internal(&exec_ctx, g_empty_slice);
+  grpc_slice_unref_internal(&exec_ctx, g_fake_path_key);
+  grpc_slice_unref_internal(&exec_ctx, g_fake_path_value);
+  grpc_slice_unref_internal(&exec_ctx, g_fake_auth_key);
+  grpc_slice_unref_internal(&exec_ctx, g_fake_auth_value);
+  grpc_exec_ctx_finish(&exec_ctx);
+}
diff --git a/src/core/ext/transport/inproc/inproc_transport.h b/src/core/ext/transport/inproc/inproc_transport.h
new file mode 100644
index 0000000000..37e6d99e99
--- /dev/null
+++ b/src/core/ext/transport/inproc/inproc_transport.h
@@ -0,0 +1,41 @@
+/*
+ *
+ * Copyright 2017 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+#ifndef GRPC_CORE_EXT_TRANSPORT_INPROC_INPROC_TRANSPORT_H
+#define GRPC_CORE_EXT_TRANSPORT_INPROC_INPROC_TRANSPORT_H
+
+#include "src/core/lib/transport/transport_impl.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+grpc_channel *grpc_inproc_channel_create(grpc_server *server,
+                                         grpc_channel_args *args,
+                                         void *reserved);
+
+extern grpc_tracer_flag grpc_inproc_trace;
+
+void grpc_inproc_transport_init(void);
+void grpc_inproc_transport_shutdown(void);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* GRPC_CORE_EXT_TRANSPORT_INPROC_INPROC_TRANSPORT_H */
diff --git a/src/core/lib/channel/channel_args.c b/src/core/lib/channel/channel_args.c
index 238d176dfa..8fdef0bc64 100644
--- a/src/core/lib/channel/channel_args.c
+++ b/src/core/lib/channel/channel_args.c
@@ -1,36 +1,23 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
+#include <grpc/support/port_platform.h>
+
 #include <limits.h>
 #include <string.h>
 
@@ -127,9 +114,23 @@ grpc_channel_args *grpc_channel_args_copy(const grpc_channel_args *src) {
   return grpc_channel_args_copy_and_add(src, NULL, 0);
 }
 
-grpc_channel_args *grpc_channel_args_merge(const grpc_channel_args *a,
+grpc_channel_args *grpc_channel_args_union(const grpc_channel_args *a,
                                            const grpc_channel_args *b) {
-  return grpc_channel_args_copy_and_add(a, b->args, b->num_args);
+  const size_t max_out = (a->num_args + b->num_args);
+  grpc_arg *uniques = gpr_malloc(sizeof(*uniques) * max_out);
+  for (size_t i = 0; i < a->num_args; ++i) uniques[i] = a->args[i];
+
+  size_t uniques_idx = a->num_args;
+  for (size_t i = 0; i < b->num_args; ++i) {
+    const char *b_key = b->args[i].key;
+    if (grpc_channel_args_find(a, b_key) == NULL) {  // not found
+      uniques[uniques_idx++] = b->args[i];
+    }
+  }
+  grpc_channel_args *result =
+      grpc_channel_args_copy_and_add(NULL, uniques, uniques_idx);
+  gpr_free(uniques);
+  return result;
 }
 
 static int cmp_arg(const grpc_arg *a, const grpc_arg *b) {
@@ -372,3 +373,29 @@ bool grpc_channel_args_want_minimal_stack(const grpc_channel_args *args) {
   return grpc_channel_arg_get_bool(
       grpc_channel_args_find(args, GRPC_ARG_MINIMAL_STACK), false);
 }
+
+grpc_arg grpc_channel_arg_string_create(char *name, char *value) {
+  grpc_arg arg;
+  arg.type = GRPC_ARG_STRING;
+  arg.key = name;
+  arg.value.string = value;
+  return arg;
+}
+
+grpc_arg grpc_channel_arg_integer_create(char *name, int value) {
+  grpc_arg arg;
+  arg.type = GRPC_ARG_INTEGER;
+  arg.key = name;
+  arg.value.integer = value;
+  return arg;
+}
+
+grpc_arg grpc_channel_arg_pointer_create(
+    char *name, void *value, const grpc_arg_pointer_vtable *vtable) {
+  grpc_arg arg;
+  arg.type = GRPC_ARG_POINTER;
+  arg.key = name;
+  arg.value.pointer.p = value;
+  arg.value.pointer.vtable = vtable;
+  return arg;
+}
diff --git a/src/core/lib/channel/channel_args.h b/src/core/lib/channel/channel_args.h
index f0f603e251..f649a8d9ec 100644
--- a/src/core/lib/channel/channel_args.h
+++ b/src/core/lib/channel/channel_args.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -63,8 +48,8 @@ grpc_channel_args *grpc_channel_args_copy_and_add_and_remove(
     const grpc_channel_args *src, const char **to_remove, size_t num_to_remove,
     const grpc_arg *to_add, size_t num_to_add);
 
-/** Concatenate args from \a a and \a b into a new instance */
-grpc_channel_args *grpc_channel_args_merge(const grpc_channel_args *a,
+/** Perform the union of \a a and \a b, prioritizing \a a entries */
+grpc_channel_args *grpc_channel_args_union(const grpc_channel_args *a,
                                            const grpc_channel_args *b);
 
 /** Destroy arguments created by \a grpc_channel_args_copy */
@@ -127,4 +112,10 @@ int grpc_channel_arg_get_integer(const grpc_arg *arg,
 
 bool grpc_channel_arg_get_bool(const grpc_arg *arg, bool default_value);
 
+// Helpers for creating channel args.
+grpc_arg grpc_channel_arg_string_create(char *name, char *value);
+grpc_arg grpc_channel_arg_integer_create(char *name, int value);
+grpc_arg grpc_channel_arg_pointer_create(char *name, void *value,
+                                         const grpc_arg_pointer_vtable *vtable);
+
 #endif /* GRPC_CORE_LIB_CHANNEL_CHANNEL_ARGS_H */
diff --git a/src/core/lib/channel/channel_stack.c b/src/core/lib/channel/channel_stack.c
index 7db54d1107..0f8e33c4be 100644
--- a/src/core/lib/channel/channel_stack.c
+++ b/src/core/lib/channel/channel_stack.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -38,7 +23,7 @@
 #include <stdlib.h>
 #include <string.h>
 
-grpc_tracer_flag grpc_trace_channel = GRPC_TRACER_INITIALIZER(false);
+grpc_tracer_flag grpc_trace_channel = GRPC_TRACER_INITIALIZER(false, "channel");
 
 /* Memory layouts.
 
diff --git a/src/core/lib/channel/channel_stack.h b/src/core/lib/channel/channel_stack.h
index c26d61b2ef..a80f8aa826 100644
--- a/src/core/lib/channel/channel_stack.h
+++ b/src/core/lib/channel/channel_stack.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -141,7 +126,7 @@ typedef struct {
   /* Destroy per call data.
      The filter does not need to do any chaining.
      The bottom filter of a stack will be passed a non-NULL pointer to
-     \a then_schedule_closure that should be passed to grpc_closure_sched when
+     \a then_schedule_closure that should be passed to GRPC_CLOSURE_SCHED when
      destruction is complete. \a final_info contains data about the completed
      call, mainly for reporting purposes. */
   void (*destroy_call_elem)(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
@@ -249,7 +234,7 @@ void grpc_call_stack_set_pollset_or_pollset_set(grpc_exec_ctx *exec_ctx,
                                                 grpc_call_stack *call_stack,
                                                 grpc_polling_entity *pollent);
 
-#ifdef GRPC_STREAM_REFCOUNT_DEBUG
+#ifndef NDEBUG
 #define GRPC_CALL_STACK_REF(call_stack, reason) \
   grpc_stream_ref(&(call_stack)->refcount, reason)
 #define GRPC_CALL_STACK_UNREF(exec_ctx, call_stack, reason) \
diff --git a/src/core/lib/channel/channel_stack_builder.c b/src/core/lib/channel/channel_stack_builder.c
index 44b030e4d1..c369e33073 100644
--- a/src/core/lib/channel/channel_stack_builder.c
+++ b/src/core/lib/channel/channel_stack_builder.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -39,7 +24,7 @@
 #include <grpc/support/string_util.h>
 
 grpc_tracer_flag grpc_trace_channel_stack_builder =
-    GRPC_TRACER_INITIALIZER(false);
+    GRPC_TRACER_INITIALIZER(false, "channel_stack_builder");
 
 typedef struct filter_node {
   struct filter_node *next;
diff --git a/src/core/lib/channel/channel_stack_builder.h b/src/core/lib/channel/channel_stack_builder.h
index 8cb36eb117..d43e427962 100644
--- a/src/core/lib/channel/channel_stack_builder.h
+++ b/src/core/lib/channel/channel_stack_builder.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/channel/connected_channel.c b/src/core/lib/channel/connected_channel.c
index d8985268eb..af06ca802e 100644
--- a/src/core/lib/channel/connected_channel.c
+++ b/src/core/lib/channel/connected_channel.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/channel/connected_channel.h b/src/core/lib/channel/connected_channel.h
index 5c7ea9ed26..10c98cce54 100644
--- a/src/core/lib/channel/connected_channel.h
+++ b/src/core/lib/channel/connected_channel.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/channel/context.h b/src/core/lib/channel/context.h
index f0a21113c5..191bd63351 100644
--- a/src/core/lib/channel/context.h
+++ b/src/core/lib/channel/context.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/channel/handshaker.c b/src/core/lib/channel/handshaker.c
index ed05b26458..c4f57a5cc8 100644
--- a/src/core/lib/channel/handshaker.c
+++ b/src/core/lib/channel/handshaker.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -205,7 +190,7 @@ static bool call_next_handshaker_locked(grpc_exec_ctx* exec_ctx,
     // Cancel deadline timer, since we're invoking the on_handshake_done
     // callback now.
     grpc_timer_cancel(exec_ctx, &mgr->deadline_timer);
-    grpc_closure_sched(exec_ctx, &mgr->on_handshake_done, error);
+    GRPC_CLOSURE_SCHED(exec_ctx, &mgr->on_handshake_done, error);
     mgr->shutdown = true;
   } else {
     grpc_handshaker_do_handshake(exec_ctx, mgr->handshakers[mgr->index],
@@ -260,13 +245,13 @@ void grpc_handshake_manager_do_handshake(
   grpc_slice_buffer_init(mgr->args.read_buffer);
   // Initialize state needed for calling handshakers.
   mgr->acceptor = acceptor;
-  grpc_closure_init(&mgr->call_next_handshaker, call_next_handshaker, mgr,
+  GRPC_CLOSURE_INIT(&mgr->call_next_handshaker, call_next_handshaker, mgr,
                     grpc_schedule_on_exec_ctx);
-  grpc_closure_init(&mgr->on_handshake_done, on_handshake_done, &mgr->args,
+  GRPC_CLOSURE_INIT(&mgr->on_handshake_done, on_handshake_done, &mgr->args,
                     grpc_schedule_on_exec_ctx);
   // Start deadline timer, which owns a ref.
   gpr_ref(&mgr->refs);
-  grpc_closure_init(&mgr->on_timeout, on_timeout, mgr,
+  GRPC_CLOSURE_INIT(&mgr->on_timeout, on_timeout, mgr,
                     grpc_schedule_on_exec_ctx);
   grpc_timer_init(exec_ctx, &mgr->deadline_timer, deadline, &mgr->on_timeout);
   // Start first handshaker, which also owns a ref.
diff --git a/src/core/lib/channel/handshaker.h b/src/core/lib/channel/handshaker.h
index 4abbbd0e7b..09b4a27c1c 100644
--- a/src/core/lib/channel/handshaker.h
+++ b/src/core/lib/channel/handshaker.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/channel/handshaker_factory.c b/src/core/lib/channel/handshaker_factory.c
index 3c30a4e1d2..4deb280c60 100644
--- a/src/core/lib/channel/handshaker_factory.c
+++ b/src/core/lib/channel/handshaker_factory.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/channel/handshaker_factory.h b/src/core/lib/channel/handshaker_factory.h
index 1984546104..6238e735dc 100644
--- a/src/core/lib/channel/handshaker_factory.h
+++ b/src/core/lib/channel/handshaker_factory.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/channel/handshaker_registry.c b/src/core/lib/channel/handshaker_registry.c
index 2e5f04064c..8c4bc3aa00 100644
--- a/src/core/lib/channel/handshaker_registry.c
+++ b/src/core/lib/channel/handshaker_registry.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/channel/handshaker_registry.h b/src/core/lib/channel/handshaker_registry.h
index 53c1b173af..a3b2ac1dc7 100644
--- a/src/core/lib/channel/handshaker_registry.h
+++ b/src/core/lib/channel/handshaker_registry.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/compression/algorithm_metadata.h b/src/core/lib/compression/algorithm_metadata.h
index 58dfe628b4..4717af6e2b 100644
--- a/src/core/lib/compression/algorithm_metadata.h
+++ b/src/core/lib/compression/algorithm_metadata.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/compression/compression.c b/src/core/lib/compression/compression.c
index ce4f597af5..8deae2798f 100644
--- a/src/core/lib/compression/compression.c
+++ b/src/core/lib/compression/compression.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/compression/message_compress.c b/src/core/lib/compression/message_compress.c
index fd3d1e6fcc..c051e28864 100644
--- a/src/core/lib/compression/message_compress.c
+++ b/src/core/lib/compression/message_compress.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/compression/message_compress.h b/src/core/lib/compression/message_compress.h
index 7bd3d98607..ca8ca37f8e 100644
--- a/src/core/lib/compression/message_compress.h
+++ b/src/core/lib/compression/message_compress.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/compression/stream_compression.c b/src/core/lib/compression/stream_compression.c
new file mode 100644
index 0000000000..df13d53e06
--- /dev/null
+++ b/src/core/lib/compression/stream_compression.c
@@ -0,0 +1,191 @@
+/*
+ *
+ * Copyright 2017 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+#include <grpc/support/alloc.h>
+#include <grpc/support/log.h>
+
+#include "src/core/lib/compression/stream_compression.h"
+#include "src/core/lib/iomgr/exec_ctx.h"
+#include "src/core/lib/slice/slice_internal.h"
+
+#define OUTPUT_BLOCK_SIZE (1024)
+
+static bool gzip_flate(grpc_stream_compression_context *ctx,
+                       grpc_slice_buffer *in, grpc_slice_buffer *out,
+                       size_t *output_size, size_t max_output_size, int flush,
+                       bool *end_of_context) {
+  GPR_ASSERT(flush == 0 || flush == Z_SYNC_FLUSH || flush == Z_FINISH);
+  /* Full flush is not allowed when inflating. */
+  GPR_ASSERT(!(ctx->flate == inflate && (flush == Z_FINISH)));
+
+  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
+  int r;
+  bool eoc = false;
+  size_t original_max_output_size = max_output_size;
+  while (max_output_size > 0 && (in->length > 0 || flush) && !eoc) {
+    size_t slice_size = max_output_size < OUTPUT_BLOCK_SIZE ? max_output_size
+                                                            : OUTPUT_BLOCK_SIZE;
+    grpc_slice slice_out = GRPC_SLICE_MALLOC(slice_size);
+    ctx->zs.avail_out = (uInt)slice_size;
+    ctx->zs.next_out = GRPC_SLICE_START_PTR(slice_out);
+    while (ctx->zs.avail_out > 0 && in->length > 0 && !eoc) {
+      grpc_slice slice = grpc_slice_buffer_take_first(in);
+      ctx->zs.avail_in = (uInt)GRPC_SLICE_LENGTH(slice);
+      ctx->zs.next_in = GRPC_SLICE_START_PTR(slice);
+      r = ctx->flate(&ctx->zs, Z_NO_FLUSH);
+      if (r < 0 && r != Z_BUF_ERROR) {
+        gpr_log(GPR_ERROR, "zlib error (%d)", r);
+        grpc_slice_unref_internal(&exec_ctx, slice_out);
+        grpc_exec_ctx_finish(&exec_ctx);
+        return false;
+      } else if (r == Z_STREAM_END && ctx->flate == inflate) {
+        eoc = true;
+      }
+      if (ctx->zs.avail_in > 0) {
+        grpc_slice_buffer_undo_take_first(
+            in,
+            grpc_slice_sub(slice, GRPC_SLICE_LENGTH(slice) - ctx->zs.avail_in,
+                           GRPC_SLICE_LENGTH(slice)));
+      }
+      grpc_slice_unref_internal(&exec_ctx, slice);
+    }
+    if (flush != 0 && ctx->zs.avail_out > 0 && !eoc) {
+      GPR_ASSERT(in->length == 0);
+      r = ctx->flate(&ctx->zs, flush);
+      if (flush == Z_SYNC_FLUSH) {
+        switch (r) {
+          case Z_OK:
+            /* Maybe flush is not complete; just made some partial progress. */
+            if (ctx->zs.avail_out > 0) {
+              flush = 0;
+            }
+            break;
+          case Z_BUF_ERROR:
+          case Z_STREAM_END:
+            flush = 0;
+            break;
+          default:
+            gpr_log(GPR_ERROR, "zlib error (%d)", r);
+            grpc_slice_unref_internal(&exec_ctx, slice_out);
+            grpc_exec_ctx_finish(&exec_ctx);
+            return false;
+        }
+      } else if (flush == Z_FINISH) {
+        switch (r) {
+          case Z_OK:
+          case Z_BUF_ERROR:
+            /* Wait for the next loop to assign additional output space. */
+            GPR_ASSERT(ctx->zs.avail_out == 0);
+            break;
+          case Z_STREAM_END:
+            flush = 0;
+            break;
+          default:
+            gpr_log(GPR_ERROR, "zlib error (%d)", r);
+            grpc_slice_unref_internal(&exec_ctx, slice_out);
+            grpc_exec_ctx_finish(&exec_ctx);
+            return false;
+        }
+      }
+    }
+
+    if (ctx->zs.avail_out == 0) {
+      grpc_slice_buffer_add(out, slice_out);
+    } else if (ctx->zs.avail_out < slice_size) {
+      slice_out.data.refcounted.length -= ctx->zs.avail_out;
+      grpc_slice_buffer_add(out, slice_out);
+    } else {
+      grpc_slice_unref_internal(&exec_ctx, slice_out);
+    }
+    max_output_size -= (slice_size - ctx->zs.avail_out);
+  }
+  grpc_exec_ctx_finish(&exec_ctx);
+  if (end_of_context) {
+    *end_of_context = eoc;
+  }
+  if (output_size) {
+    *output_size = original_max_output_size - max_output_size;
+  }
+  return true;
+}
+
+bool grpc_stream_compress(grpc_stream_compression_context *ctx,
+                          grpc_slice_buffer *in, grpc_slice_buffer *out,
+                          size_t *output_size, size_t max_output_size,
+                          grpc_stream_compression_flush flush) {
+  GPR_ASSERT(ctx->flate == deflate);
+  int gzip_flush;
+  switch (flush) {
+    case GRPC_STREAM_COMPRESSION_FLUSH_NONE:
+      gzip_flush = 0;
+      break;
+    case GRPC_STREAM_COMPRESSION_FLUSH_SYNC:
+      gzip_flush = Z_SYNC_FLUSH;
+      break;
+    case GRPC_STREAM_COMPRESSION_FLUSH_FINISH:
+      gzip_flush = Z_FINISH;
+      break;
+    default:
+      gzip_flush = 0;
+  }
+  return gzip_flate(ctx, in, out, output_size, max_output_size, gzip_flush,
+                    NULL);
+}
+
+bool grpc_stream_decompress(grpc_stream_compression_context *ctx,
+                            grpc_slice_buffer *in, grpc_slice_buffer *out,
+                            size_t *output_size, size_t max_output_size,
+                            bool *end_of_context) {
+  GPR_ASSERT(ctx->flate == inflate);
+  return gzip_flate(ctx, in, out, output_size, max_output_size, Z_SYNC_FLUSH,
+                    end_of_context);
+}
+
+grpc_stream_compression_context *grpc_stream_compression_context_create(
+    grpc_stream_compression_method method) {
+  grpc_stream_compression_context *ctx =
+      gpr_zalloc(sizeof(grpc_stream_compression_context));
+  int r;
+  if (ctx == NULL) {
+    return NULL;
+  }
+  if (method == GRPC_STREAM_COMPRESSION_DECOMPRESS) {
+    r = inflateInit2(&ctx->zs, 0x1F);
+    ctx->flate = inflate;
+  } else {
+    r = deflateInit2(&ctx->zs, Z_DEFAULT_COMPRESSION, Z_DEFLATED, 0x1F, 8,
+                     Z_DEFAULT_STRATEGY);
+    ctx->flate = deflate;
+  }
+  if (r != Z_OK) {
+    gpr_free(ctx);
+    return NULL;
+  }
+
+  return ctx;
+}
+
+void grpc_stream_compression_context_destroy(
+    grpc_stream_compression_context *ctx) {
+  if (ctx->flate == inflate) {
+    inflateEnd(&ctx->zs);
+  } else {
+    deflateEnd(&ctx->zs);
+  }
+  gpr_free(ctx);
+}
diff --git a/src/core/lib/compression/stream_compression.h b/src/core/lib/compression/stream_compression.h
new file mode 100644
index 0000000000..844dff81a3
--- /dev/null
+++ b/src/core/lib/compression/stream_compression.h
@@ -0,0 +1,90 @@
+/*
+ *
+ * Copyright 2017 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+#ifndef GRPC_CORE_LIB_COMPRESSION_STREAM_COMPRESSION_H
+#define GRPC_CORE_LIB_COMPRESSION_STREAM_COMPRESSION_H
+
+#include <stdbool.h>
+
+#include <grpc/slice_buffer.h>
+#include <zlib.h>
+
+/* Stream compression/decompression context */
+typedef struct grpc_stream_compression_context {
+  z_stream zs;
+  int (*flate)(z_stream *zs, int flush);
+} grpc_stream_compression_context;
+
+typedef enum grpc_stream_compression_method {
+  GRPC_STREAM_COMPRESSION_COMPRESS = 0,
+  GRPC_STREAM_COMPRESSION_DECOMPRESS,
+  GRPC_STREAM_COMPRESSION_METHOD_COUNT
+} grpc_stream_compression_method;
+
+typedef enum grpc_stream_compression_flush {
+  GRPC_STREAM_COMPRESSION_FLUSH_NONE = 0,
+  GRPC_STREAM_COMPRESSION_FLUSH_SYNC,
+  GRPC_STREAM_COMPRESSION_FLUSH_FINISH,
+  GRPC_STREAM_COMPRESSION_FLUSH_COUNT
+} grpc_stream_compression_flush;
+
+/**
+ * Compress bytes provided in \a in with a given context, with an optional flush
+ * at the end of compression. Emits at most \a max_output_size compressed bytes
+ * into \a out. If all the bytes in input buffer \a in are depleted and \a flush
+ * is not GRPC_STREAM_COMPRESSION_FLUSH_NONE, the corresponding flush method is
+ * executed. The total number of bytes emitted is outputed in \a output_size.
+ *
+ * A SYNC flush indicates that the entire messages in \a in can be decompressed
+ * from \a out. A FINISH flush implies a SYNC flush, and that any further
+ * compression will not be dependent on the state of the current context and any
+ * previous compressed bytes. It allows corresponding decompression context to
+ * be dropped when reaching this boundary.
+ */
+bool grpc_stream_compress(grpc_stream_compression_context *ctx,
+                          grpc_slice_buffer *in, grpc_slice_buffer *out,
+                          size_t *output_size, size_t max_output_size,
+                          grpc_stream_compression_flush flush);
+
+/**
+ * Decompress bytes provided in \a in with a given context. Emits at most \a
+ * max_output_size decompressed bytes into \a out. If decompression process
+ * reached the end of a gzip stream, \a end_of_context is set to true; otherwise
+ * it is set to false. The total number of bytes emitted is outputed in \a
+ * output_size.
+ */
+bool grpc_stream_decompress(grpc_stream_compression_context *ctx,
+                            grpc_slice_buffer *in, grpc_slice_buffer *out,
+                            size_t *output_size, size_t max_output_size,
+                            bool *end_of_context);
+
+/**
+ * Creates a stream compression context. \a pending_bytes_buffer is the input
+ * buffer for compression/decompression operations. \a method specifies whether
+ * the context is for compression or decompression.
+ */
+grpc_stream_compression_context *grpc_stream_compression_context_create(
+    grpc_stream_compression_method method);
+
+/**
+ * Destroys a stream compression context.
+ */
+void grpc_stream_compression_context_destroy(
+    grpc_stream_compression_context *ctx);
+
+#endif
diff --git a/src/core/lib/debug/trace.c b/src/core/lib/debug/trace.c
index 4dfea44c57..c6c1853e20 100644
--- a/src/core/lib/debug/trace.c
+++ b/src/core/lib/debug/trace.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -42,7 +27,6 @@
 int grpc_tracer_set_enabled(const char *name, int enabled);
 
 typedef struct tracer {
-  const char *name;
   grpc_tracer_flag *flag;
   struct tracer *next;
 } tracer;
@@ -54,9 +38,8 @@ static tracer *tracers;
 #define TRACER_SET(flag, on) (flag).value = (on)
 #endif
 
-void grpc_register_tracer(const char *name, grpc_tracer_flag *flag) {
+void grpc_register_tracer(grpc_tracer_flag *flag) {
   tracer *t = gpr_malloc(sizeof(*t));
-  t->name = name;
   t->flag = flag;
   t->next = tracers;
   TRACER_SET(*flag, false);
@@ -108,6 +91,14 @@ static void parse(const char *s) {
   gpr_free(strings);
 }
 
+static void list_tracers() {
+  gpr_log(GPR_DEBUG, "available tracers:");
+  tracer *t;
+  for (t = tracers; t; t = t->next) {
+    gpr_log(GPR_DEBUG, "\t%s", t->flag->name);
+  }
+}
+
 void grpc_tracer_init(const char *env_var) {
   char *e = gpr_getenv(env_var);
   if (e != NULL) {
@@ -130,10 +121,18 @@ int grpc_tracer_set_enabled(const char *name, int enabled) {
     for (t = tracers; t; t = t->next) {
       TRACER_SET(*t->flag, enabled);
     }
+  } else if (0 == strcmp(name, "list_tracers")) {
+    list_tracers();
+  } else if (0 == strcmp(name, "refcount")) {
+    for (t = tracers; t; t = t->next) {
+      if (strstr(t->flag->name, "refcount") != NULL) {
+        TRACER_SET(*t->flag, enabled);
+      }
+    }
   } else {
     int found = 0;
     for (t = tracers; t; t = t->next) {
-      if (0 == strcmp(name, t->name)) {
+      if (0 == strcmp(name, t->flag->name)) {
         TRACER_SET(*t->flag, enabled);
         found = 1;
       }
diff --git a/src/core/lib/debug/trace.h b/src/core/lib/debug/trace.h
index ba432574d0..dd9e6a30fe 100644
--- a/src/core/lib/debug/trace.h
+++ b/src/core/lib/debug/trace.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -50,19 +35,20 @@ typedef struct {
 #else
   bool value;
 #endif
+  char *name;
 } grpc_tracer_flag;
 
 #ifdef GRPC_THREADSAFE_TRACER
 #define GRPC_TRACER_ON(flag) (gpr_atm_no_barrier_load(&(flag).value) != 0)
-#define GRPC_TRACER_INITIALIZER(on) \
-  { (gpr_atm)(on) }
+#define GRPC_TRACER_INITIALIZER(on, name) \
+  { (gpr_atm)(on), (name) }
 #else
 #define GRPC_TRACER_ON(flag) ((flag).value)
-#define GRPC_TRACER_INITIALIZER(on) \
-  { (on) }
+#define GRPC_TRACER_INITIALIZER(on, name) \
+  { (on), (name) }
 #endif
 
-void grpc_register_tracer(const char *name, grpc_tracer_flag *flag);
+void grpc_register_tracer(grpc_tracer_flag *flag);
 void grpc_tracer_init(const char *env_var_name);
 void grpc_tracer_shutdown(void);
 
diff --git a/src/core/lib/http/format_request.c b/src/core/lib/http/format_request.c
index 024664b6ee..f887726eea 100644
--- a/src/core/lib/http/format_request.c
+++ b/src/core/lib/http/format_request.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/http/format_request.h b/src/core/lib/http/format_request.h
index 1c8e3f68c5..12b42e42fa 100644
--- a/src/core/lib/http/format_request.h
+++ b/src/core/lib/http/format_request.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/http/httpcli.c b/src/core/lib/http/httpcli.c
index f1a3abd1e9..97db3a3c57 100644
--- a/src/core/lib/http/httpcli.c
+++ b/src/core/lib/http/httpcli.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -40,6 +25,7 @@
 #include <grpc/support/string_util.h>
 #include <grpc/support/useful.h>
 
+#include "src/core/lib/channel/channel_args.h"
 #include "src/core/lib/http/format_request.h"
 #include "src/core/lib/http/parser.h"
 #include "src/core/lib/iomgr/endpoint.h"
@@ -105,7 +91,7 @@ static void finish(grpc_exec_ctx *exec_ctx, internal_request *req,
                    grpc_error *error) {
   grpc_polling_entity_del_from_pollset_set(exec_ctx, req->pollent,
                                            req->context->pollset_set);
-  grpc_closure_sched(exec_ctx, req->on_done, GRPC_ERROR_REF(error));
+  GRPC_CLOSURE_SCHED(exec_ctx, req->on_done, error);
   grpc_http_parser_destroy(&req->parser);
   if (req->addresses != NULL) {
     grpc_resolved_addresses_destroy(req->addresses);
@@ -228,13 +214,11 @@ static void next_address(grpc_exec_ctx *exec_ctx, internal_request *req,
     return;
   }
   addr = &req->addresses->addrs[req->next_address++];
-  grpc_closure_init(&req->connected, on_connected, req,
+  GRPC_CLOSURE_INIT(&req->connected, on_connected, req,
                     grpc_schedule_on_exec_ctx);
-  grpc_arg arg;
-  arg.key = GRPC_ARG_RESOURCE_QUOTA;
-  arg.type = GRPC_ARG_POINTER;
-  arg.value.pointer.p = req->resource_quota;
-  arg.value.pointer.vtable = grpc_resource_quota_arg_vtable();
+  grpc_arg arg = grpc_channel_arg_pointer_create(
+      GRPC_ARG_RESOURCE_QUOTA, req->resource_quota,
+      grpc_resource_quota_arg_vtable());
   grpc_channel_args args = {1, &arg};
   grpc_tcp_client_connect(exec_ctx, &req->connected, &req->ep,
                           req->context->pollset_set, &args, addr,
@@ -244,7 +228,7 @@ static void next_address(grpc_exec_ctx *exec_ctx, internal_request *req,
 static void on_resolved(grpc_exec_ctx *exec_ctx, void *arg, grpc_error *error) {
   internal_request *req = arg;
   if (error != GRPC_ERROR_NONE) {
-    finish(exec_ctx, req, error);
+    finish(exec_ctx, req, GRPC_ERROR_REF(error));
     return;
   }
   req->next_address = 0;
@@ -271,8 +255,8 @@ static void internal_request_begin(grpc_exec_ctx *exec_ctx,
   req->pollent = pollent;
   req->overall_error = GRPC_ERROR_NONE;
   req->resource_quota = grpc_resource_quota_ref_internal(resource_quota);
-  grpc_closure_init(&req->on_read, on_read, req, grpc_schedule_on_exec_ctx);
-  grpc_closure_init(&req->done_write, done_write, req,
+  GRPC_CLOSURE_INIT(&req->on_read, on_read, req, grpc_schedule_on_exec_ctx);
+  GRPC_CLOSURE_INIT(&req->done_write, done_write, req,
                     grpc_schedule_on_exec_ctx);
   grpc_slice_buffer_init(&req->incoming);
   grpc_slice_buffer_init(&req->outgoing);
@@ -286,7 +270,7 @@ static void internal_request_begin(grpc_exec_ctx *exec_ctx,
   grpc_resolve_address(
       exec_ctx, request->host, req->handshaker->default_port,
       req->context->pollset_set,
-      grpc_closure_create(on_resolved, req, grpc_schedule_on_exec_ctx),
+      GRPC_CLOSURE_CREATE(on_resolved, req, grpc_schedule_on_exec_ctx),
       &req->addresses);
 }
 
diff --git a/src/core/lib/http/httpcli.h b/src/core/lib/http/httpcli.h
index ad994fd811..a3baf512a3 100644
--- a/src/core/lib/http/httpcli.h
+++ b/src/core/lib/http/httpcli.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/http/httpcli_security_connector.c b/src/core/lib/http/httpcli_security_connector.c
index fd25a8d3e0..37ee08783e 100644
--- a/src/core/lib/http/httpcli_security_connector.c
+++ b/src/core/lib/http/httpcli_security_connector.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -40,10 +25,12 @@
 #include <grpc/support/string_util.h>
 
 #include "src/core/lib/channel/channel_args.h"
+#include "src/core/lib/channel/handshaker_registry.h"
 #include "src/core/lib/security/transport/security_handshaker.h"
 #include "src/core/lib/slice/slice_internal.h"
 #include "src/core/lib/support/string.h"
 #include "src/core/tsi/ssl_transport_security.h"
+#include "src/core/tsi/transport_security_adapter.h"
 
 typedef struct {
   grpc_channel_security_connector base;
@@ -78,7 +65,8 @@ static void httpcli_ssl_add_handshakers(grpc_exec_ctx *exec_ctx,
   }
   grpc_handshake_manager_add(
       handshake_mgr,
-      grpc_security_handshaker_create(exec_ctx, handshaker, &sc->base));
+      grpc_security_handshaker_create(
+          exec_ctx, tsi_create_adapter_handshaker(handshaker), &sc->base));
 }
 
 static void httpcli_ssl_check_peer(grpc_exec_ctx *exec_ctx,
@@ -98,7 +86,7 @@ static void httpcli_ssl_check_peer(grpc_exec_ctx *exec_ctx,
     error = GRPC_ERROR_CREATE_FROM_COPIED_STRING(msg);
     gpr_free(msg);
   }
-  grpc_closure_sched(exec_ctx, on_peer_checked, error);
+  GRPC_CLOSURE_SCHED(exec_ctx, on_peer_checked, error);
   tsi_peer_destruct(&peer);
 }
 
@@ -170,7 +158,6 @@ static void ssl_handshake(grpc_exec_ctx *exec_ctx, void *arg,
                           grpc_millis deadline,
                           void (*on_done)(grpc_exec_ctx *exec_ctx, void *arg,
                                           grpc_endpoint *endpoint)) {
-  grpc_channel_security_connector *sc = NULL;
   on_done_closure *c = gpr_malloc(sizeof(*c));
   const char *pem_root_certs = grpc_get_default_ssl_roots();
   if (pem_root_certs == NULL) {
@@ -181,11 +168,13 @@ static void ssl_handshake(grpc_exec_ctx *exec_ctx, void *arg,
   }
   c->func = on_done;
   c->arg = arg;
-  c->handshake_mgr = grpc_handshake_manager_create();
+  grpc_channel_security_connector *sc = NULL;
   GPR_ASSERT(httpcli_ssl_channel_security_connector_create(
                  exec_ctx, pem_root_certs, host, &sc) == GRPC_SECURITY_OK);
-  grpc_channel_security_connector_add_handshakers(exec_ctx, sc,
-                                                  c->handshake_mgr);
+  grpc_arg channel_arg = grpc_security_connector_to_arg(&sc->base);
+  grpc_channel_args args = {1, &channel_arg};
+  c->handshake_mgr = grpc_handshake_manager_create();
+  grpc_handshakers_add(exec_ctx, HANDSHAKER_CLIENT, &args, c->handshake_mgr);
   grpc_handshake_manager_do_handshake(
       exec_ctx, c->handshake_mgr, tcp, NULL /* channel_args */, deadline,
       NULL /* acceptor */, on_handshake_done, c /* user_data */);
diff --git a/src/core/lib/http/parser.c b/src/core/lib/http/parser.c
index a4357978e4..9c5e93f4e5 100644
--- a/src/core/lib/http/parser.c
+++ b/src/core/lib/http/parser.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -40,7 +25,7 @@
 #include <grpc/support/log.h>
 #include <grpc/support/useful.h>
 
-grpc_tracer_flag grpc_http1_trace = GRPC_TRACER_INITIALIZER(false);
+grpc_tracer_flag grpc_http1_trace = GRPC_TRACER_INITIALIZER(false, "http1");
 
 static char *buf2str(void *buffer, size_t length) {
   char *out = gpr_malloc(length + 1);
diff --git a/src/core/lib/http/parser.h b/src/core/lib/http/parser.h
index a155fecf11..c8dced3901 100644
--- a/src/core/lib/http/parser.h
+++ b/src/core/lib/http/parser.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/closure.c b/src/core/lib/iomgr/closure.c
index 8ef0b210ad..26f9cbe0fa 100644
--- a/src/core/lib/iomgr/closure.c
+++ b/src/core/lib/iomgr/closure.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -39,14 +24,30 @@
 
 #include "src/core/lib/profiling/timers.h"
 
+#ifndef NDEBUG
+grpc_tracer_flag grpc_trace_closure = GRPC_TRACER_INITIALIZER(false, "closure");
+#endif
+
+#ifndef NDEBUG
+grpc_closure *grpc_closure_init(const char *file, int line,
+                                grpc_closure *closure, grpc_iomgr_cb_func cb,
+                                void *cb_arg,
+                                grpc_closure_scheduler *scheduler) {
+#else
 grpc_closure *grpc_closure_init(grpc_closure *closure, grpc_iomgr_cb_func cb,
                                 void *cb_arg,
                                 grpc_closure_scheduler *scheduler) {
+#endif
   closure->cb = cb;
   closure->cb_arg = cb_arg;
   closure->scheduler = scheduler;
 #ifndef NDEBUG
   closure->scheduled = false;
+  closure->file_initiated = NULL;
+  closure->line_initiated = 0;
+  closure->run = false;
+  closure->file_created = file;
+  closure->line_created = line;
 #endif
   return closure;
 }
@@ -115,19 +116,39 @@ static void closure_wrapper(grpc_exec_ctx *exec_ctx, void *arg,
   cb(exec_ctx, cb_arg, error);
 }
 
+#ifndef NDEBUG
+grpc_closure *grpc_closure_create(const char *file, int line,
+                                  grpc_iomgr_cb_func cb, void *cb_arg,
+                                  grpc_closure_scheduler *scheduler) {
+#else
 grpc_closure *grpc_closure_create(grpc_iomgr_cb_func cb, void *cb_arg,
                                   grpc_closure_scheduler *scheduler) {
+#endif
   wrapped_closure *wc = gpr_malloc(sizeof(*wc));
   wc->cb = cb;
   wc->cb_arg = cb_arg;
+#ifndef NDEBUG
+  grpc_closure_init(file, line, &wc->wrapper, closure_wrapper, wc, scheduler);
+#else
   grpc_closure_init(&wc->wrapper, closure_wrapper, wc, scheduler);
+#endif
   return &wc->wrapper;
 }
 
+#ifndef NDEBUG
+void grpc_closure_run(const char *file, int line, grpc_exec_ctx *exec_ctx,
+                      grpc_closure *c, grpc_error *error) {
+#else
 void grpc_closure_run(grpc_exec_ctx *exec_ctx, grpc_closure *c,
                       grpc_error *error) {
+#endif
   GPR_TIMER_BEGIN("grpc_closure_run", 0);
   if (c != NULL) {
+#ifndef NDEBUG
+    c->file_initiated = file;
+    c->line_initiated = line;
+    c->run = true;
+#endif
     assert(c->cb);
     c->scheduler->vtable->run(exec_ctx, c, error);
   } else {
@@ -136,13 +157,21 @@ void grpc_closure_run(grpc_exec_ctx *exec_ctx, grpc_closure *c,
   GPR_TIMER_END("grpc_closure_run", 0);
 }
 
+#ifndef NDEBUG
+void grpc_closure_sched(const char *file, int line, grpc_exec_ctx *exec_ctx,
+                        grpc_closure *c, grpc_error *error) {
+#else
 void grpc_closure_sched(grpc_exec_ctx *exec_ctx, grpc_closure *c,
                         grpc_error *error) {
+#endif
   GPR_TIMER_BEGIN("grpc_closure_sched", 0);
   if (c != NULL) {
 #ifndef NDEBUG
     GPR_ASSERT(!c->scheduled);
     c->scheduled = true;
+    c->file_initiated = file;
+    c->line_initiated = line;
+    c->run = false;
 #endif
     assert(c->cb);
     c->scheduler->vtable->sched(exec_ctx, c, error);
@@ -152,13 +181,21 @@ void grpc_closure_sched(grpc_exec_ctx *exec_ctx, grpc_closure *c,
   GPR_TIMER_END("grpc_closure_sched", 0);
 }
 
+#ifndef NDEBUG
+void grpc_closure_list_sched(const char *file, int line,
+                             grpc_exec_ctx *exec_ctx, grpc_closure_list *list) {
+#else
 void grpc_closure_list_sched(grpc_exec_ctx *exec_ctx, grpc_closure_list *list) {
+#endif
   grpc_closure *c = list->head;
   while (c != NULL) {
     grpc_closure *next = c->next_data.next;
 #ifndef NDEBUG
     GPR_ASSERT(!c->scheduled);
     c->scheduled = true;
+    c->file_initiated = file;
+    c->line_initiated = line;
+    c->run = false;
 #endif
     assert(c->cb);
     c->scheduler->vtable->sched(exec_ctx, c, c->error_data.error);
diff --git a/src/core/lib/iomgr/closure.h b/src/core/lib/iomgr/closure.h
index 2bedbf00d6..cd32a4ba38 100644
--- a/src/core/lib/iomgr/closure.h
+++ b/src/core/lib/iomgr/closure.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -41,9 +26,17 @@
 #include "src/core/lib/iomgr/error.h"
 #include "src/core/lib/support/mpscq.h"
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 struct grpc_closure;
 typedef struct grpc_closure grpc_closure;
 
+#ifndef NDEBUG
+extern grpc_tracer_flag grpc_trace_closure;
+#endif
+
 typedef struct grpc_closure_list {
   grpc_closure *head;
   grpc_closure *tail;
@@ -53,7 +46,9 @@ typedef struct grpc_closure_list {
  *
  * \param arg Arbitrary input.
  * \param error GRPC_ERROR_NONE if no error occurred, otherwise some grpc_error
- *              describing what went wrong */
+ *              describing what went wrong.
+ *              Error contract: it is not the cb's job to unref this error;
+ *              the closure scheduler will do that after the cb returns */
 typedef void (*grpc_iomgr_cb_func)(grpc_exec_ctx *exec_ctx, void *arg,
                                    grpc_error *error);
 
@@ -100,19 +95,47 @@ struct grpc_closure {
     uintptr_t scratch;
   } error_data;
 
+// extra tracing and debugging for grpc_closure. This incurs a decent amount of
+// overhead per closure, so it must be enabled at compile time.
 #ifndef NDEBUG
   bool scheduled;
+  bool run;  // true = run, false = scheduled
+  const char *file_created;
+  int line_created;
+  const char *file_initiated;
+  int line_initiated;
 #endif
 };
 
 /** Initializes \a closure with \a cb and \a cb_arg. Returns \a closure. */
+#ifndef NDEBUG
+grpc_closure *grpc_closure_init(const char *file, int line,
+                                grpc_closure *closure, grpc_iomgr_cb_func cb,
+                                void *cb_arg,
+                                grpc_closure_scheduler *scheduler);
+#define GRPC_CLOSURE_INIT(closure, cb, cb_arg, scheduler) \
+  grpc_closure_init(__FILE__, __LINE__, closure, cb, cb_arg, scheduler)
+#else
 grpc_closure *grpc_closure_init(grpc_closure *closure, grpc_iomgr_cb_func cb,
                                 void *cb_arg,
                                 grpc_closure_scheduler *scheduler);
+#define GRPC_CLOSURE_INIT(closure, cb, cb_arg, scheduler) \
+  grpc_closure_init(closure, cb, cb_arg, scheduler)
+#endif
 
 /* Create a heap allocated closure: try to avoid except for very rare events */
+#ifndef NDEBUG
+grpc_closure *grpc_closure_create(const char *file, int line,
+                                  grpc_iomgr_cb_func cb, void *cb_arg,
+                                  grpc_closure_scheduler *scheduler);
+#define GRPC_CLOSURE_CREATE(cb, cb_arg, scheduler) \
+  grpc_closure_create(__FILE__, __LINE__, cb, cb_arg, scheduler)
+#else
 grpc_closure *grpc_closure_create(grpc_iomgr_cb_func cb, void *cb_arg,
                                   grpc_closure_scheduler *scheduler);
+#define GRPC_CLOSURE_CREATE(cb, cb_arg, scheduler) \
+  grpc_closure_create(cb, cb_arg, scheduler)
+#endif
 
 #define GRPC_CLOSURE_LIST_INIT \
   { NULL, NULL }
@@ -138,16 +161,48 @@ bool grpc_closure_list_empty(grpc_closure_list list);
 /** Run a closure directly. Caller ensures that no locks are being held above.
  *  Note that calling this at the end of a closure callback function itself is
  *  by definition safe. */
+#ifndef NDEBUG
+void grpc_closure_run(const char *file, int line, grpc_exec_ctx *exec_ctx,
+                      grpc_closure *closure, grpc_error *error);
+#define GRPC_CLOSURE_RUN(exec_ctx, closure, error) \
+  grpc_closure_run(__FILE__, __LINE__, exec_ctx, closure, error)
+#else
 void grpc_closure_run(grpc_exec_ctx *exec_ctx, grpc_closure *closure,
                       grpc_error *error);
+#define GRPC_CLOSURE_RUN(exec_ctx, closure, error) \
+  grpc_closure_run(exec_ctx, closure, error)
+#endif
 
 /** Schedule a closure to be run. Does not need to be run from a safe point. */
+#ifndef NDEBUG
+void grpc_closure_sched(const char *file, int line, grpc_exec_ctx *exec_ctx,
+                        grpc_closure *closure, grpc_error *error);
+#define GRPC_CLOSURE_SCHED(exec_ctx, closure, error) \
+  grpc_closure_sched(__FILE__, __LINE__, exec_ctx, closure, error)
+#else
 void grpc_closure_sched(grpc_exec_ctx *exec_ctx, grpc_closure *closure,
                         grpc_error *error);
+#define GRPC_CLOSURE_SCHED(exec_ctx, closure, error) \
+  grpc_closure_sched(exec_ctx, closure, error)
+#endif
 
 /** Schedule all closures in a list to be run. Does not need to be run from a
  * safe point. */
+#ifndef NDEBUG
+void grpc_closure_list_sched(const char *file, int line,
+                             grpc_exec_ctx *exec_ctx,
+                             grpc_closure_list *closure_list);
+#define GRPC_CLOSURE_LIST_SCHED(exec_ctx, closure_list) \
+  grpc_closure_list_sched(__FILE__, __LINE__, exec_ctx, closure_list)
+#else
 void grpc_closure_list_sched(grpc_exec_ctx *exec_ctx,
                              grpc_closure_list *closure_list);
+#define GRPC_CLOSURE_LIST_SCHED(exec_ctx, closure_list) \
+  grpc_closure_list_sched(exec_ctx, closure_list)
+#endif
+
+#ifdef __cplusplus
+}
+#endif
 
 #endif /* GRPC_CORE_LIB_IOMGR_CLOSURE_H */
diff --git a/src/core/lib/iomgr/combiner.c b/src/core/lib/iomgr/combiner.c
index 863f22c614..c72c37e2b5 100644
--- a/src/core/lib/iomgr/combiner.c
+++ b/src/core/lib/iomgr/combiner.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -39,10 +24,11 @@
 #include <grpc/support/alloc.h>
 #include <grpc/support/log.h>
 
-#include "src/core/lib/iomgr/workqueue.h"
+#include "src/core/lib/iomgr/executor.h"
 #include "src/core/lib/profiling/timers.h"
 
-grpc_tracer_flag grpc_combiner_trace = GRPC_TRACER_INITIALIZER(false);
+grpc_tracer_flag grpc_combiner_trace =
+    GRPC_TRACER_INITIALIZER(false, "combiner");
 
 #define GRPC_COMBINER_TRACE(fn)                \
   do {                                         \
@@ -56,93 +42,47 @@ grpc_tracer_flag grpc_combiner_trace = GRPC_TRACER_INITIALIZER(false);
 
 struct grpc_combiner {
   grpc_combiner *next_combiner_on_this_exec_ctx;
-  grpc_workqueue *optional_workqueue;
-  grpc_closure_scheduler uncovered_scheduler;
-  grpc_closure_scheduler covered_scheduler;
-  grpc_closure_scheduler uncovered_finally_scheduler;
-  grpc_closure_scheduler covered_finally_scheduler;
+  grpc_closure_scheduler scheduler;
+  grpc_closure_scheduler finally_scheduler;
   gpr_mpscq queue;
+  // either:
+  // a pointer to the initiating exec ctx if that is the only exec_ctx that has
+  // ever queued to this combiner, or NULL. If this is non-null, it's not
+  // dereferencable (since the initiating exec_ctx may have gone out of scope)
+  gpr_atm initiating_exec_ctx_or_null;
   // state is:
   // lower bit - zero if orphaned (STATE_UNORPHANED)
   // other bits - number of items queued on the lock (STATE_ELEM_COUNT_LOW_BIT)
   gpr_atm state;
-  // number of elements in the list that are covered by a poller: if >0, we can
-  // offload safely
-  gpr_atm elements_covered_by_poller;
   bool time_to_execute_final_list;
-  bool final_list_covered_by_poller;
   grpc_closure_list final_list;
   grpc_closure offload;
   gpr_refcount refs;
 };
 
-static void combiner_exec_uncovered(grpc_exec_ctx *exec_ctx,
-                                    grpc_closure *closure, grpc_error *error);
-static void combiner_exec_covered(grpc_exec_ctx *exec_ctx,
+static void combiner_exec(grpc_exec_ctx *exec_ctx, grpc_closure *closure,
+                          grpc_error *error);
+static void combiner_finally_exec(grpc_exec_ctx *exec_ctx,
                                   grpc_closure *closure, grpc_error *error);
-static void combiner_finally_exec_uncovered(grpc_exec_ctx *exec_ctx,
-                                            grpc_closure *closure,
-                                            grpc_error *error);
-static void combiner_finally_exec_covered(grpc_exec_ctx *exec_ctx,
-                                          grpc_closure *closure,
-                                          grpc_error *error);
-
-static const grpc_closure_scheduler_vtable scheduler_uncovered = {
-    combiner_exec_uncovered, combiner_exec_uncovered,
-    "combiner:immediately:uncovered"};
-static const grpc_closure_scheduler_vtable scheduler_covered = {
-    combiner_exec_covered, combiner_exec_covered,
-    "combiner:immediately:covered"};
-static const grpc_closure_scheduler_vtable finally_scheduler_uncovered = {
-    combiner_finally_exec_uncovered, combiner_finally_exec_uncovered,
-    "combiner:finally:uncovered"};
-static const grpc_closure_scheduler_vtable finally_scheduler_covered = {
-    combiner_finally_exec_covered, combiner_finally_exec_covered,
-    "combiner:finally:covered"};
 
-static void offload(grpc_exec_ctx *exec_ctx, void *arg, grpc_error *error);
-
-typedef struct {
-  grpc_error *error;
-  bool covered_by_poller;
-} error_data;
-
-static uintptr_t pack_error_data(error_data d) {
-  return ((uintptr_t)d.error) | (d.covered_by_poller ? 1 : 0);
-}
-
-static error_data unpack_error_data(uintptr_t p) {
-  return (error_data){(grpc_error *)(p & ~(uintptr_t)1), p & 1};
-}
+static const grpc_closure_scheduler_vtable scheduler = {
+    combiner_exec, combiner_exec, "combiner:immediately"};
+static const grpc_closure_scheduler_vtable finally_scheduler = {
+    combiner_finally_exec, combiner_finally_exec, "combiner:finally"};
 
-static bool is_covered_by_poller(grpc_combiner *lock) {
-  return lock->final_list_covered_by_poller ||
-         gpr_atm_acq_load(&lock->elements_covered_by_poller) > 0;
-}
-
-#define IS_COVERED_BY_POLLER_FMT "(final=%d elems=%" PRIdPTR ")->%d"
-#define IS_COVERED_BY_POLLER_ARGS(lock)                      \
-  (lock)->final_list_covered_by_poller,                      \
-      gpr_atm_acq_load(&(lock)->elements_covered_by_poller), \
-      is_covered_by_poller((lock))
+static void offload(grpc_exec_ctx *exec_ctx, void *arg, grpc_error *error);
 
-grpc_combiner *grpc_combiner_create(grpc_workqueue *optional_workqueue) {
+grpc_combiner *grpc_combiner_create(void) {
   grpc_combiner *lock = gpr_malloc(sizeof(*lock));
   gpr_ref_init(&lock->refs, 1);
   lock->next_combiner_on_this_exec_ctx = NULL;
   lock->time_to_execute_final_list = false;
-  lock->optional_workqueue = optional_workqueue;
-  lock->final_list_covered_by_poller = false;
-  lock->uncovered_scheduler.vtable = &scheduler_uncovered;
-  lock->covered_scheduler.vtable = &scheduler_covered;
-  lock->uncovered_finally_scheduler.vtable = &finally_scheduler_uncovered;
-  lock->covered_finally_scheduler.vtable = &finally_scheduler_covered;
+  lock->scheduler.vtable = &scheduler;
+  lock->finally_scheduler.vtable = &finally_scheduler;
   gpr_atm_no_barrier_store(&lock->state, STATE_UNORPHANED);
-  gpr_atm_no_barrier_store(&lock->elements_covered_by_poller, 0);
   gpr_mpscq_init(&lock->queue);
   grpc_closure_list_init(&lock->final_list);
-  grpc_closure_init(&lock->offload, offload, lock,
-                    grpc_workqueue_scheduler(lock->optional_workqueue));
+  GRPC_CLOSURE_INIT(&lock->offload, offload, lock, grpc_executor_scheduler);
   GRPC_COMBINER_TRACE(gpr_log(GPR_DEBUG, "C:%p create", lock));
   return lock;
 }
@@ -151,7 +91,6 @@ static void really_destroy(grpc_exec_ctx *exec_ctx, grpc_combiner *lock) {
   GRPC_COMBINER_TRACE(gpr_log(GPR_DEBUG, "C:%p really_destroy", lock));
   GPR_ASSERT(gpr_atm_no_barrier_load(&lock->state) == 0);
   gpr_mpscq_destroy(&lock->queue);
-  GRPC_WORKQUEUE_UNREF(exec_ctx, lock->optional_workqueue, "combiner");
   gpr_free(lock);
 }
 
@@ -164,12 +103,14 @@ static void start_destroy(grpc_exec_ctx *exec_ctx, grpc_combiner *lock) {
   }
 }
 
-#ifdef GRPC_COMBINER_REFCOUNT_DEBUG
-#define GRPC_COMBINER_DEBUG_SPAM(op, delta)                               \
-  gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,                             \
-          "combiner[%p] %s %" PRIdPTR " --> %" PRIdPTR " %s", lock, (op), \
-          gpr_atm_no_barrier_load(&lock->refs.count),                     \
-          gpr_atm_no_barrier_load(&lock->refs.count) + (delta), reason);
+#ifndef NDEBUG
+#define GRPC_COMBINER_DEBUG_SPAM(op, delta)                                \
+  if (GRPC_TRACER_ON(grpc_combiner_trace)) {                               \
+    gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,                            \
+            "C:%p %s %" PRIdPTR " --> %" PRIdPTR " %s", lock, (op),        \
+            gpr_atm_no_barrier_load(&lock->refs.count),                    \
+            gpr_atm_no_barrier_load(&lock->refs.count) + (delta), reason); \
+  }
 #else
 #define GRPC_COMBINER_DEBUG_SPAM(op, delta)
 #endif
@@ -208,48 +149,40 @@ static void push_first_on_exec_ctx(grpc_exec_ctx *exec_ctx,
   }
 }
 
-static void combiner_exec(grpc_exec_ctx *exec_ctx, grpc_combiner *lock,
-                          grpc_closure *cl, grpc_error *error,
-                          bool covered_by_poller) {
+#define COMBINER_FROM_CLOSURE_SCHEDULER(closure, scheduler_name) \
+  ((grpc_combiner *)(((char *)((closure)->scheduler)) -          \
+                     offsetof(grpc_combiner, scheduler_name)))
+
+static void combiner_exec(grpc_exec_ctx *exec_ctx, grpc_closure *cl,
+                          grpc_error *error) {
   GPR_TIMER_BEGIN("combiner.execute", 0);
+  grpc_combiner *lock = COMBINER_FROM_CLOSURE_SCHEDULER(cl, scheduler);
   gpr_atm last = gpr_atm_full_fetch_add(&lock->state, STATE_ELEM_COUNT_LOW_BIT);
-  GRPC_COMBINER_TRACE(gpr_log(
-      GPR_DEBUG, "C:%p grpc_combiner_execute c=%p cov=%d last=%" PRIdPTR, lock,
-      cl, covered_by_poller, last));
-  GPR_ASSERT(last & STATE_UNORPHANED);  // ensure lock has not been destroyed
-  assert(cl->cb);
-  cl->error_data.scratch =
-      pack_error_data((error_data){error, covered_by_poller});
-  if (covered_by_poller) {
-    gpr_atm_no_barrier_fetch_add(&lock->elements_covered_by_poller, 1);
-  }
-  gpr_mpscq_push(&lock->queue, &cl->next_data.atm_next);
+  GRPC_COMBINER_TRACE(gpr_log(GPR_DEBUG,
+                              "C:%p grpc_combiner_execute c=%p last=%" PRIdPTR,
+                              lock, cl, last));
   if (last == 1) {
+    gpr_atm_no_barrier_store(&lock->initiating_exec_ctx_or_null,
+                             (gpr_atm)exec_ctx);
     // first element on this list: add it to the list of combiner locks
     // executing within this exec_ctx
     push_last_on_exec_ctx(exec_ctx, lock);
+  } else {
+    // there may be a race with setting here: if that happens, we may delay
+    // offload for one or two actions, and that's fine
+    gpr_atm initiator =
+        gpr_atm_no_barrier_load(&lock->initiating_exec_ctx_or_null);
+    if (initiator != 0 && initiator != (gpr_atm)exec_ctx) {
+      gpr_atm_no_barrier_store(&lock->initiating_exec_ctx_or_null, 0);
+    }
   }
+  GPR_ASSERT(last & STATE_UNORPHANED);  // ensure lock has not been destroyed
+  assert(cl->cb);
+  cl->error_data.error = error;
+  gpr_mpscq_push(&lock->queue, &cl->next_data.atm_next);
   GPR_TIMER_END("combiner.execute", 0);
 }
 
-#define COMBINER_FROM_CLOSURE_SCHEDULER(closure, scheduler_name) \
-  ((grpc_combiner *)(((char *)((closure)->scheduler)) -          \
-                     offsetof(grpc_combiner, scheduler_name)))
-
-static void combiner_exec_uncovered(grpc_exec_ctx *exec_ctx, grpc_closure *cl,
-                                    grpc_error *error) {
-  combiner_exec(exec_ctx,
-                COMBINER_FROM_CLOSURE_SCHEDULER(cl, uncovered_scheduler), cl,
-                error, false);
-}
-
-static void combiner_exec_covered(grpc_exec_ctx *exec_ctx, grpc_closure *cl,
-                                  grpc_error *error) {
-  combiner_exec(exec_ctx,
-                COMBINER_FROM_CLOSURE_SCHEDULER(cl, covered_scheduler), cl,
-                error, true);
-}
-
 static void move_next(grpc_exec_ctx *exec_ctx) {
   exec_ctx->active_combiner =
       exec_ctx->active_combiner->next_combiner_on_this_exec_ctx;
@@ -265,9 +198,8 @@ static void offload(grpc_exec_ctx *exec_ctx, void *arg, grpc_error *error) {
 
 static void queue_offload(grpc_exec_ctx *exec_ctx, grpc_combiner *lock) {
   move_next(exec_ctx);
-  GRPC_COMBINER_TRACE(gpr_log(GPR_DEBUG, "C:%p queue_offload --> %p", lock,
-                              lock->optional_workqueue));
-  grpc_closure_sched(exec_ctx, &lock->offload, GRPC_ERROR_NONE);
+  GRPC_COMBINER_TRACE(gpr_log(GPR_DEBUG, "C:%p queue_offload", lock));
+  GRPC_CLOSURE_SCHED(exec_ctx, &lock->offload, GRPC_ERROR_NONE);
 }
 
 bool grpc_combiner_continue_exec_ctx(grpc_exec_ctx *exec_ctx) {
@@ -278,22 +210,23 @@ bool grpc_combiner_continue_exec_ctx(grpc_exec_ctx *exec_ctx) {
     return false;
   }
 
-  GRPC_COMBINER_TRACE(
-      gpr_log(GPR_DEBUG,
-              "C:%p grpc_combiner_continue_exec_ctx workqueue=%p "
-              "is_covered_by_poller=" IS_COVERED_BY_POLLER_FMT
-              " exec_ctx_ready_to_finish=%d "
-              "time_to_execute_final_list=%d",
-              lock, lock->optional_workqueue, IS_COVERED_BY_POLLER_ARGS(lock),
-              grpc_exec_ctx_ready_to_finish(exec_ctx),
-              lock->time_to_execute_final_list));
-
-  if (lock->optional_workqueue != NULL && is_covered_by_poller(lock) &&
-      grpc_exec_ctx_ready_to_finish(exec_ctx)) {
+  bool contended =
+      gpr_atm_no_barrier_load(&lock->initiating_exec_ctx_or_null) == 0;
+
+  GRPC_COMBINER_TRACE(gpr_log(GPR_DEBUG,
+                              "C:%p grpc_combiner_continue_exec_ctx "
+                              "contended=%d "
+                              "exec_ctx_ready_to_finish=%d "
+                              "time_to_execute_final_list=%d",
+                              lock, contended,
+                              grpc_exec_ctx_ready_to_finish(exec_ctx),
+                              lock->time_to_execute_final_list));
+
+  if (contended && grpc_exec_ctx_ready_to_finish(exec_ctx) &&
+      grpc_executor_is_threaded()) {
     GPR_TIMER_MARK("offload_from_finished_exec_ctx", 0);
-    // this execution context wants to move on, and we have a workqueue (and
-    // so can help the execution context out): schedule remaining work to be
-    // picked up on the workqueue
+    // this execution context wants to move on: schedule remaining work to be
+    // picked up on the executor
     queue_offload(exec_ctx, lock);
     GPR_TIMER_END("combiner.continue_exec_ctx", 0);
     return true;
@@ -310,29 +243,23 @@ bool grpc_combiner_continue_exec_ctx(grpc_exec_ctx *exec_ctx) {
       // queue is in an inconsistent state: use this as a cue that we should
       // go off and do something else for a while (and come back later)
       GPR_TIMER_MARK("delay_busy", 0);
-      if (lock->optional_workqueue != NULL && is_covered_by_poller(lock)) {
-        queue_offload(exec_ctx, lock);
-      }
+      queue_offload(exec_ctx, lock);
       GPR_TIMER_END("combiner.continue_exec_ctx", 0);
       return true;
     }
     GPR_TIMER_BEGIN("combiner.exec1", 0);
     grpc_closure *cl = (grpc_closure *)n;
-    error_data err = unpack_error_data(cl->error_data.scratch);
+    grpc_error *cl_err = cl->error_data.error;
 #ifndef NDEBUG
     cl->scheduled = false;
 #endif
-    cl->cb(exec_ctx, cl->cb_arg, err.error);
-    if (err.covered_by_poller) {
-      gpr_atm_no_barrier_fetch_add(&lock->elements_covered_by_poller, -1);
-    }
-    GRPC_ERROR_UNREF(err.error);
+    cl->cb(exec_ctx, cl->cb_arg, cl_err);
+    GRPC_ERROR_UNREF(cl_err);
     GPR_TIMER_END("combiner.exec1", 0);
   } else {
     grpc_closure *c = lock->final_list.head;
     GPR_ASSERT(c != NULL);
     grpc_closure_list_init(&lock->final_list);
-    lock->final_list_covered_by_poller = false;
     int loops = 0;
     while (c != NULL) {
       GPR_TIMER_BEGIN("combiner.exec_1final", 0);
@@ -398,20 +325,20 @@ bool grpc_combiner_continue_exec_ctx(grpc_exec_ctx *exec_ctx) {
 static void enqueue_finally(grpc_exec_ctx *exec_ctx, void *closure,
                             grpc_error *error);
 
-static void combiner_execute_finally(grpc_exec_ctx *exec_ctx,
-                                     grpc_combiner *lock, grpc_closure *closure,
-                                     grpc_error *error,
-                                     bool covered_by_poller) {
-  GRPC_COMBINER_TRACE(gpr_log(
-      GPR_DEBUG, "C:%p grpc_combiner_execute_finally c=%p; ac=%p; cov=%d", lock,
-      closure, exec_ctx->active_combiner, covered_by_poller));
+static void combiner_finally_exec(grpc_exec_ctx *exec_ctx,
+                                  grpc_closure *closure, grpc_error *error) {
+  grpc_combiner *lock =
+      COMBINER_FROM_CLOSURE_SCHEDULER(closure, finally_scheduler);
+  GRPC_COMBINER_TRACE(gpr_log(GPR_DEBUG,
+                              "C:%p grpc_combiner_execute_finally c=%p; ac=%p",
+                              lock, closure, exec_ctx->active_combiner));
   GPR_TIMER_BEGIN("combiner.execute_finally", 0);
   if (exec_ctx->active_combiner != lock) {
     GPR_TIMER_MARK("slowpath", 0);
-    grpc_closure_sched(
-        exec_ctx, grpc_closure_create(enqueue_finally, closure,
-                                      grpc_combiner_scheduler(lock, false)),
-        error);
+    GRPC_CLOSURE_SCHED(exec_ctx,
+                       GRPC_CLOSURE_CREATE(enqueue_finally, closure,
+                                           grpc_combiner_scheduler(lock)),
+                       error);
     GPR_TIMER_END("combiner.execute_finally", 0);
     return;
   }
@@ -419,42 +346,20 @@ static void combiner_execute_finally(grpc_exec_ctx *exec_ctx,
   if (grpc_closure_list_empty(lock->final_list)) {
     gpr_atm_full_fetch_add(&lock->state, STATE_ELEM_COUNT_LOW_BIT);
   }
-  if (covered_by_poller) {
-    lock->final_list_covered_by_poller = true;
-  }
   grpc_closure_list_append(&lock->final_list, closure, error);
   GPR_TIMER_END("combiner.execute_finally", 0);
 }
 
 static void enqueue_finally(grpc_exec_ctx *exec_ctx, void *closure,
                             grpc_error *error) {
-  combiner_execute_finally(exec_ctx, exec_ctx->active_combiner, closure,
-                           GRPC_ERROR_REF(error), false);
-}
-
-static void combiner_finally_exec_uncovered(grpc_exec_ctx *exec_ctx,
-                                            grpc_closure *cl,
-                                            grpc_error *error) {
-  combiner_execute_finally(exec_ctx, COMBINER_FROM_CLOSURE_SCHEDULER(
-                                         cl, uncovered_finally_scheduler),
-                           cl, error, false);
-}
-
-static void combiner_finally_exec_covered(grpc_exec_ctx *exec_ctx,
-                                          grpc_closure *cl, grpc_error *error) {
-  combiner_execute_finally(
-      exec_ctx, COMBINER_FROM_CLOSURE_SCHEDULER(cl, covered_finally_scheduler),
-      cl, error, true);
+  combiner_finally_exec(exec_ctx, closure, GRPC_ERROR_REF(error));
 }
 
-grpc_closure_scheduler *grpc_combiner_scheduler(grpc_combiner *combiner,
-                                                bool covered_by_poller) {
-  return covered_by_poller ? &combiner->covered_scheduler
-                           : &combiner->uncovered_scheduler;
+grpc_closure_scheduler *grpc_combiner_scheduler(grpc_combiner *combiner) {
+  return &combiner->scheduler;
 }
 
 grpc_closure_scheduler *grpc_combiner_finally_scheduler(
-    grpc_combiner *combiner, bool covered_by_poller) {
-  return covered_by_poller ? &combiner->covered_finally_scheduler
-                           : &combiner->uncovered_finally_scheduler;
+    grpc_combiner *combiner) {
+  return &combiner->finally_scheduler;
 }
diff --git a/src/core/lib/iomgr/combiner.h b/src/core/lib/iomgr/combiner.h
index 6ab7a2b26b..8e0434369d 100644
--- a/src/core/lib/iomgr/combiner.h
+++ b/src/core/lib/iomgr/combiner.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -48,10 +33,9 @@
 
 // Initialize the lock, with an optional workqueue to shift load to when
 // necessary
-grpc_combiner *grpc_combiner_create(grpc_workqueue *optional_workqueue);
+grpc_combiner *grpc_combiner_create(void);
 
-//#define GRPC_COMBINER_REFCOUNT_DEBUG
-#ifdef GRPC_COMBINER_REFCOUNT_DEBUG
+#ifndef NDEBUG
 #define GRPC_COMBINER_DEBUG_ARGS \
   , const char *file, int line, const char *reason
 #define GRPC_COMBINER_REF(combiner, reason) \
@@ -71,11 +55,9 @@ grpc_combiner *grpc_combiner_ref(grpc_combiner *lock GRPC_COMBINER_DEBUG_ARGS);
 void grpc_combiner_unref(grpc_exec_ctx *exec_ctx,
                          grpc_combiner *lock GRPC_COMBINER_DEBUG_ARGS);
 // Fetch a scheduler to schedule closures against
-grpc_closure_scheduler *grpc_combiner_scheduler(grpc_combiner *lock,
-                                                bool covered_by_poller);
+grpc_closure_scheduler *grpc_combiner_scheduler(grpc_combiner *lock);
 // Scheduler to execute \a action within the lock just prior to unlocking.
-grpc_closure_scheduler *grpc_combiner_finally_scheduler(grpc_combiner *lock,
-                                                        bool covered_by_poller);
+grpc_closure_scheduler *grpc_combiner_finally_scheduler(grpc_combiner *lock);
 
 bool grpc_combiner_continue_exec_ctx(grpc_exec_ctx *exec_ctx);
 
diff --git a/src/core/lib/iomgr/endpoint.c b/src/core/lib/iomgr/endpoint.c
index bf6e98146a..37cce335ca 100644
--- a/src/core/lib/iomgr/endpoint.c
+++ b/src/core/lib/iomgr/endpoint.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -69,10 +54,6 @@ char* grpc_endpoint_get_peer(grpc_endpoint* ep) {
 
 int grpc_endpoint_get_fd(grpc_endpoint* ep) { return ep->vtable->get_fd(ep); }
 
-grpc_workqueue* grpc_endpoint_get_workqueue(grpc_endpoint* ep) {
-  return ep->vtable->get_workqueue(ep);
-}
-
 grpc_resource_user* grpc_endpoint_get_resource_user(grpc_endpoint* ep) {
   return ep->vtable->get_resource_user(ep);
 }
diff --git a/src/core/lib/iomgr/endpoint.h b/src/core/lib/iomgr/endpoint.h
index 740357ecc5..8f0523a981 100644
--- a/src/core/lib/iomgr/endpoint.h
+++ b/src/core/lib/iomgr/endpoint.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -52,7 +37,6 @@ struct grpc_endpoint_vtable {
                grpc_slice_buffer *slices, grpc_closure *cb);
   void (*write)(grpc_exec_ctx *exec_ctx, grpc_endpoint *ep,
                 grpc_slice_buffer *slices, grpc_closure *cb);
-  grpc_workqueue *(*get_workqueue)(grpc_endpoint *ep);
   void (*add_to_pollset)(grpc_exec_ctx *exec_ctx, grpc_endpoint *ep,
                          grpc_pollset *pollset);
   void (*add_to_pollset_set)(grpc_exec_ctx *exec_ctx, grpc_endpoint *ep,
@@ -78,9 +62,6 @@ char *grpc_endpoint_get_peer(grpc_endpoint *ep);
    */
 int grpc_endpoint_get_fd(grpc_endpoint *ep);
 
-/* Retrieve a reference to the workqueue associated with this endpoint */
-grpc_workqueue *grpc_endpoint_get_workqueue(grpc_endpoint *ep);
-
 /* Write slices out to the socket.
 
    If the connection is ready for more data after the end of the call, it
diff --git a/src/core/lib/iomgr/endpoint_pair.h b/src/core/lib/iomgr/endpoint_pair.h
index 6407a6ad3f..b60e62fc3e 100644
--- a/src/core/lib/iomgr/endpoint_pair.h
+++ b/src/core/lib/iomgr/endpoint_pair.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/endpoint_pair_posix.c b/src/core/lib/iomgr/endpoint_pair_posix.c
index 5542a372d8..3ade2148ba 100644
--- a/src/core/lib/iomgr/endpoint_pair_posix.c
+++ b/src/core/lib/iomgr/endpoint_pair_posix.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/endpoint_pair_uv.c b/src/core/lib/iomgr/endpoint_pair_uv.c
index 9718eb0523..ff72fe0492 100644
--- a/src/core/lib/iomgr/endpoint_pair_uv.c
+++ b/src/core/lib/iomgr/endpoint_pair_uv.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/endpoint_pair_windows.c b/src/core/lib/iomgr/endpoint_pair_windows.c
index 25d6264dfb..782fa2fd69 100644
--- a/src/core/lib/iomgr/endpoint_pair_windows.c
+++ b/src/core/lib/iomgr/endpoint_pair_windows.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/error.c b/src/core/lib/iomgr/error.c
index 5f2c989aad..3759dda992 100644
--- a/src/core/lib/iomgr/error.c
+++ b/src/core/lib/iomgr/error.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -45,10 +30,16 @@
 #include <grpc/support/log_windows.h>
 #endif
 
+#include "src/core/lib/debug/trace.h"
 #include "src/core/lib/iomgr/error_internal.h"
 #include "src/core/lib/profiling/timers.h"
 #include "src/core/lib/slice/slice_internal.h"
 
+#ifndef NDEBUG
+grpc_tracer_flag grpc_trace_error_refcount =
+    GRPC_TRACER_INITIALIZER(false, "error_refcount");
+#endif
+
 static const char *error_int_name(grpc_error_ints key) {
   switch (key) {
     case GRPC_ERROR_INT_ERRNO:
@@ -134,14 +125,14 @@ bool grpc_error_is_special(grpc_error *err) {
          err == GRPC_ERROR_CANCELLED;
 }
 
-#ifdef GRPC_ERROR_REFCOUNT_DEBUG
-grpc_error *grpc_error_ref(grpc_error *err, const char *file, int line,
-                           const char *func) {
+#ifndef NDEBUG
+grpc_error *grpc_error_ref(grpc_error *err, const char *file, int line) {
   if (grpc_error_is_special(err)) return err;
-  gpr_log(GPR_DEBUG, "%p: %" PRIdPTR " -> %" PRIdPTR " [%s:%d %s]", err,
-          gpr_atm_no_barrier_load(&err->atomics.refs.count),
-          gpr_atm_no_barrier_load(&err->atomics.refs.count) + 1, file, line,
-          func);
+  if (GRPC_TRACER_ON(grpc_trace_error_refcount)) {
+    gpr_log(GPR_DEBUG, "%p: %" PRIdPTR " -> %" PRIdPTR " [%s:%d]", err,
+            gpr_atm_no_barrier_load(&err->atomics.refs.count),
+            gpr_atm_no_barrier_load(&err->atomics.refs.count) + 1, file, line);
+  }
   gpr_ref(&err->atomics.refs);
   return err;
 }
@@ -187,14 +178,14 @@ static void error_destroy(grpc_error *err) {
   gpr_free(err);
 }
 
-#ifdef GRPC_ERROR_REFCOUNT_DEBUG
-void grpc_error_unref(grpc_error *err, const char *file, int line,
-                      const char *func) {
+#ifndef NDEBUG
+void grpc_error_unref(grpc_error *err, const char *file, int line) {
   if (grpc_error_is_special(err)) return;
-  gpr_log(GPR_DEBUG, "%p: %" PRIdPTR " -> %" PRIdPTR " [%s:%d %s]", err,
-          gpr_atm_no_barrier_load(&err->atomics.refs.count),
-          gpr_atm_no_barrier_load(&err->atomics.refs.count) - 1, file, line,
-          func);
+  if (GRPC_TRACER_ON(grpc_trace_error_refcount)) {
+    gpr_log(GPR_DEBUG, "%p: %" PRIdPTR " -> %" PRIdPTR " [%s:%d]", err,
+            gpr_atm_no_barrier_load(&err->atomics.refs.count),
+            gpr_atm_no_barrier_load(&err->atomics.refs.count) - 1, file, line);
+  }
   if (gpr_unref(&err->atomics.refs)) {
     error_destroy(err);
   }
@@ -217,13 +208,17 @@ static uint8_t get_placement(grpc_error **err, size_t size) {
     if ((*err)->arena_size + slots > (*err)->arena_capacity) {
       return UINT8_MAX;
     }
-#ifdef GRPC_ERROR_REFCOUNT_DEBUG
+#ifndef NDEBUG
     grpc_error *orig = *err;
 #endif
     *err = gpr_realloc(
         *err, sizeof(grpc_error) + (*err)->arena_capacity * sizeof(intptr_t));
-#ifdef GRPC_ERROR_REFCOUNT_DEBUG
-    if (*err != orig) gpr_log(GPR_DEBUG, "realloc %p -> %p", orig, *err);
+#ifndef NDEBUG
+    if (GRPC_TRACER_ON(grpc_trace_error_refcount)) {
+      if (*err != orig) {
+        gpr_log(GPR_DEBUG, "realloc %p -> %p", orig, *err);
+      }
+    }
 #endif
   }
   uint8_t placement = (*err)->arena_size;
@@ -331,8 +326,10 @@ grpc_error *grpc_error_create(const char *file, int line, grpc_slice desc,
   if (err == NULL) {  // TODO(ctiller): make gpr_malloc return NULL
     return GRPC_ERROR_OOM;
   }
-#ifdef GRPC_ERROR_REFCOUNT_DEBUG
-  gpr_log(GPR_DEBUG, "%p create [%s:%d]", err, file, line);
+#ifndef NDEBUG
+  if (GRPC_TRACER_ON(grpc_trace_error_refcount)) {
+    gpr_log(GPR_DEBUG, "%p create [%s:%d]", err, file, line);
+  }
 #endif
 
   err->arena_size = 0;
@@ -410,8 +407,10 @@ static grpc_error *copy_error_and_unref(grpc_error *in) {
       new_arena_capacity = (uint8_t)(3 * new_arena_capacity / 2);
     }
     out = gpr_malloc(sizeof(*in) + new_arena_capacity * sizeof(intptr_t));
-#ifdef GRPC_ERROR_REFCOUNT_DEBUG
-    gpr_log(GPR_DEBUG, "%p create copying %p", out, in);
+#ifndef NDEBUG
+    if (GRPC_TRACER_ON(grpc_trace_error_refcount)) {
+      gpr_log(GPR_DEBUG, "%p create copying %p", out, in);
+    }
 #endif
     // bulk memcpy of the rest of the struct.
     size_t skip = sizeof(&out->atomics);
@@ -769,7 +768,7 @@ grpc_error *grpc_os_error(const char *file, int line, int err,
               GRPC_ERROR_INT_ERRNO, err),
           GRPC_ERROR_STR_OS_ERROR,
           grpc_slice_from_static_string(strerror(err))),
-      GRPC_ERROR_STR_SYSCALL, grpc_slice_from_static_string(call_name));
+      GRPC_ERROR_STR_SYSCALL, grpc_slice_from_copied_string(call_name));
 }
 
 #ifdef GPR_WINDOWS
diff --git a/src/core/lib/iomgr/error.h b/src/core/lib/iomgr/error.h
index 34b24d9263..b362948691 100644
--- a/src/core/lib/iomgr/error.h
+++ b/src/core/lib/iomgr/error.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -41,6 +26,8 @@
 #include <grpc/status.h>
 #include <grpc/support/time.h>
 
+#include "src/core/lib/debug/trace.h"
+
 #ifdef __cplusplus
 extern "C" {
 #endif
@@ -51,6 +38,10 @@ extern "C" {
 
 typedef struct grpc_error grpc_error;
 
+#ifndef NDEBUG
+extern grpc_tracer_flag grpc_trace_error_refcount;
+#endif
+
 typedef enum {
   /// 'errno' from the operating system
   GRPC_ERROR_INT_ERRNO,
@@ -164,15 +155,11 @@ grpc_error *grpc_error_create(const char *file, int line, grpc_slice desc,
   grpc_error_create(__FILE__, __LINE__, grpc_slice_from_copied_string(desc), \
                     errs, count)
 
-//#define GRPC_ERROR_REFCOUNT_DEBUG
-#ifdef GRPC_ERROR_REFCOUNT_DEBUG
-grpc_error *grpc_error_ref(grpc_error *err, const char *file, int line,
-                           const char *func);
-void grpc_error_unref(grpc_error *err, const char *file, int line,
-                      const char *func);
-#define GRPC_ERROR_REF(err) grpc_error_ref(err, __FILE__, __LINE__, __func__)
-#define GRPC_ERROR_UNREF(err) \
-  grpc_error_unref(err, __FILE__, __LINE__, __func__)
+#ifndef NDEBUG
+grpc_error *grpc_error_ref(grpc_error *err, const char *file, int line);
+void grpc_error_unref(grpc_error *err, const char *file, int line);
+#define GRPC_ERROR_REF(err) grpc_error_ref(err, __FILE__, __LINE__)
+#define GRPC_ERROR_UNREF(err) grpc_error_unref(err, __FILE__, __LINE__)
 #else
 grpc_error *grpc_error_ref(grpc_error *err);
 void grpc_error_unref(grpc_error *err);
diff --git a/src/core/lib/iomgr/error_internal.h b/src/core/lib/iomgr/error_internal.h
index 7f204df1b2..7507484557 100644
--- a/src/core/lib/iomgr/error_internal.h
+++ b/src/core/lib/iomgr/error_internal.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/ev_epoll1_linux.c b/src/core/lib/iomgr/ev_epoll1_linux.c
index ad69f808cd..66ba601adb 100644
--- a/src/core/lib/iomgr/ev_epoll1_linux.c
+++ b/src/core/lib/iomgr/ev_epoll1_linux.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2017, Google Inc.
- * All rights reserved.
+ * Copyright 2017 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -58,7 +43,6 @@
 #include "src/core/lib/iomgr/iomgr_internal.h"
 #include "src/core/lib/iomgr/lockfree_event.h"
 #include "src/core/lib/iomgr/wakeup_fd_posix.h"
-#include "src/core/lib/iomgr/workqueue.h"
 #include "src/core/lib/profiling/timers.h"
 #include "src/core/lib/support/block_annotate.h"
 
@@ -130,7 +114,9 @@ struct grpc_pollset {
  * Pollset-set Declarations
  */
 
-struct grpc_pollset_set {};
+struct grpc_pollset_set {
+  char unused;
+};
 
 /*******************************************************************************
  * Common helpers
@@ -208,8 +194,10 @@ static grpc_fd *fd_create(int fd, const char *name) {
   char *fd_name;
   gpr_asprintf(&fd_name, "%s fd=%d", name, fd);
   grpc_iomgr_register_object(&new_fd->iomgr_object, fd_name);
-#ifdef GRPC_FD_REF_COUNT_DEBUG
-  gpr_log(GPR_DEBUG, "FD %d %p create %s", fd, (void *)new_fd, fd_name);
+#ifndef NDEBUG
+  if (GRPC_TRACER_ON(grpc_trace_fd_refcount)) {
+    gpr_log(GPR_DEBUG, "FD %d %p create %s", fd, new_fd, fd_name);
+  }
 #endif
   gpr_free(fd_name);
 
@@ -251,7 +239,7 @@ static void fd_orphan(grpc_exec_ctx *exec_ctx, grpc_fd *fd,
     close(fd->fd);
   }
 
-  grpc_closure_sched(exec_ctx, on_done, GRPC_ERROR_REF(error));
+  GRPC_CLOSURE_SCHED(exec_ctx, on_done, GRPC_ERROR_REF(error));
 
   grpc_iomgr_unregister_object(&fd->iomgr_object);
   grpc_lfev_destroy(&fd->read_closure);
@@ -283,10 +271,6 @@ static void fd_notify_on_write(grpc_exec_ctx *exec_ctx, grpc_fd *fd,
   grpc_lfev_notify_on(exec_ctx, &fd->write_closure, closure);
 }
 
-static grpc_workqueue *fd_get_workqueue(grpc_fd *fd) {
-  return (grpc_workqueue *)0xb0b51ed;
-}
-
 static void fd_become_readable(grpc_exec_ctx *exec_ctx, grpc_fd *fd,
                                grpc_pollset *notifier) {
   grpc_lfev_set_ready(exec_ctx, &fd->read_closure);
@@ -313,8 +297,6 @@ GPR_TLS_DECL(g_current_thread_worker);
 static gpr_atm g_active_poller;
 static pollset_neighbourhood *g_neighbourhoods;
 static size_t g_num_neighbourhoods;
-static gpr_mu g_wq_mu;
-static grpc_closure_list g_wq_items;
 
 /* Return true if first in list */
 static bool worker_insert(grpc_pollset *pollset, grpc_pollset_worker *worker) {
@@ -363,8 +345,6 @@ static grpc_error *pollset_global_init(void) {
   gpr_atm_no_barrier_store(&g_active_poller, 0);
   global_wakeup_fd.read_fd = -1;
   grpc_error *err = grpc_wakeup_fd_init(&global_wakeup_fd);
-  gpr_mu_init(&g_wq_mu);
-  g_wq_items = (grpc_closure_list)GRPC_CLOSURE_LIST_INIT;
   if (err != GRPC_ERROR_NONE) return err;
   struct epoll_event ev = {.events = (uint32_t)(EPOLLIN | EPOLLET),
                            .data.ptr = &global_wakeup_fd};
@@ -383,7 +363,6 @@ static grpc_error *pollset_global_init(void) {
 static void pollset_global_shutdown(void) {
   gpr_tls_destroy(&g_current_thread_pollset);
   gpr_tls_destroy(&g_current_thread_worker);
-  gpr_mu_destroy(&g_wq_mu);
   if (global_wakeup_fd.read_fd != -1) grpc_wakeup_fd_destroy(&global_wakeup_fd);
   for (size_t i = 0; i < g_num_neighbourhoods; i++) {
     gpr_mu_destroy(&g_neighbourhoods[i].mu);
@@ -450,7 +429,7 @@ static void pollset_maybe_finish_shutdown(grpc_exec_ctx *exec_ctx,
                                           grpc_pollset *pollset) {
   if (pollset->shutdown_closure != NULL && pollset->root_worker == NULL &&
       pollset->begin_refs == 0) {
-    grpc_closure_sched(exec_ctx, pollset->shutdown_closure, GRPC_ERROR_NONE);
+    GRPC_CLOSURE_SCHED(exec_ctx, pollset->shutdown_closure, GRPC_ERROR_NONE);
     pollset->shutdown_closure = NULL;
   }
 }
@@ -507,9 +486,6 @@ static grpc_error *pollset_epoll(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
   for (int i = 0; i < r; i++) {
     void *data_ptr = events[i].data.ptr;
     if (data_ptr == &global_wakeup_fd) {
-      gpr_mu_lock(&g_wq_mu);
-      grpc_closure_list_move(&g_wq_items, &exec_ctx->closure_list);
-      gpr_mu_unlock(&g_wq_mu);
       append_error(&error, grpc_wakeup_fd_consume_wakeup(&global_wakeup_fd),
                    err_desc);
     } else {
@@ -792,84 +768,6 @@ static void pollset_add_fd(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
                            grpc_fd *fd) {}
 
 /*******************************************************************************
- * Workqueue Definitions
- */
-
-#ifdef GRPC_WORKQUEUE_REFCOUNT_DEBUG
-static grpc_workqueue *workqueue_ref(grpc_workqueue *workqueue,
-                                     const char *file, int line,
-                                     const char *reason) {
-  return workqueue;
-}
-
-static void workqueue_unref(grpc_exec_ctx *exec_ctx, grpc_workqueue *workqueue,
-                            const char *file, int line, const char *reason) {}
-#else
-static grpc_workqueue *workqueue_ref(grpc_workqueue *workqueue) {
-  return workqueue;
-}
-
-static void workqueue_unref(grpc_exec_ctx *exec_ctx,
-                            grpc_workqueue *workqueue) {}
-#endif
-
-static void wq_sched(grpc_exec_ctx *exec_ctx, grpc_closure *closure,
-                     grpc_error *error) {
-  // find a neighbourhood to wakeup
-  bool scheduled = false;
-  size_t initial_neighbourhood = choose_neighbourhood();
-  for (size_t i = 0; !scheduled && i < g_num_neighbourhoods; i++) {
-    pollset_neighbourhood *neighbourhood =
-        &g_neighbourhoods[(initial_neighbourhood + i) % g_num_neighbourhoods];
-    if (gpr_mu_trylock(&neighbourhood->mu)) {
-      if (neighbourhood->active_root != NULL) {
-        grpc_pollset *inspect = neighbourhood->active_root;
-        do {
-          if (gpr_mu_trylock(&inspect->mu)) {
-            if (inspect->root_worker != NULL) {
-              grpc_pollset_worker *inspect_worker = inspect->root_worker;
-              do {
-                if (inspect_worker->kick_state == UNKICKED) {
-                  inspect_worker->kick_state = KICKED;
-                  grpc_closure_list_append(
-                      &inspect_worker->schedule_on_end_work, closure, error);
-                  if (inspect_worker->initialized_cv) {
-                    gpr_cv_signal(&inspect_worker->cv);
-                  }
-                  scheduled = true;
-                }
-                inspect_worker = inspect_worker->next;
-              } while (!scheduled && inspect_worker != inspect->root_worker);
-            }
-            gpr_mu_unlock(&inspect->mu);
-          }
-          inspect = inspect->next;
-        } while (!scheduled && inspect != neighbourhood->active_root);
-      }
-      gpr_mu_unlock(&neighbourhood->mu);
-    }
-  }
-  if (!scheduled) {
-    gpr_mu_lock(&g_wq_mu);
-    grpc_closure_list_append(&g_wq_items, closure, error);
-    gpr_mu_unlock(&g_wq_mu);
-    GRPC_LOG_IF_ERROR("workqueue_scheduler",
-                      grpc_wakeup_fd_wakeup(&global_wakeup_fd));
-  }
-}
-
-static const grpc_closure_scheduler_vtable
-    singleton_workqueue_scheduler_vtable = {wq_sched, wq_sched,
-                                            "epoll1_workqueue"};
-
-static grpc_closure_scheduler singleton_workqueue_scheduler = {
-    &singleton_workqueue_scheduler_vtable};
-
-static grpc_closure_scheduler *workqueue_scheduler(grpc_workqueue *workqueue) {
-  return &singleton_workqueue_scheduler;
-}
-
-/*******************************************************************************
  * Pollset-set Definitions
  */
 
@@ -920,7 +818,6 @@ static const grpc_event_engine_vtable vtable = {
     .fd_notify_on_read = fd_notify_on_read,
     .fd_notify_on_write = fd_notify_on_write,
     .fd_get_read_notifier_pollset = fd_get_read_notifier_pollset,
-    .fd_get_workqueue = fd_get_workqueue,
 
     .pollset_init = pollset_init,
     .pollset_shutdown = pollset_shutdown,
@@ -938,10 +835,6 @@ static const grpc_event_engine_vtable vtable = {
     .pollset_set_add_fd = pollset_set_add_fd,
     .pollset_set_del_fd = pollset_set_del_fd,
 
-    .workqueue_ref = workqueue_ref,
-    .workqueue_unref = workqueue_unref,
-    .workqueue_scheduler = workqueue_scheduler,
-
     .shutdown_engine = shutdown_engine,
 };
 
diff --git a/src/core/lib/iomgr/ev_epoll1_linux.h b/src/core/lib/iomgr/ev_epoll1_linux.h
index bd52478a7c..0696e0df40 100644
--- a/src/core/lib/iomgr/ev_epoll1_linux.h
+++ b/src/core/lib/iomgr/ev_epoll1_linux.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2017, Google Inc.
- * All rights reserved.
+ * Copyright 2017 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/ev_epoll_limited_pollers_linux.c b/src/core/lib/iomgr/ev_epoll_limited_pollers_linux.c
index d23bf6c06c..9f82c480bc 100644
--- a/src/core/lib/iomgr/ev_epoll_limited_pollers_linux.c
+++ b/src/core/lib/iomgr/ev_epoll_limited_pollers_linux.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2017, Google Inc.
- * All rights reserved.
+ * Copyright 2017 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -61,7 +46,6 @@
 #include "src/core/lib/iomgr/lockfree_event.h"
 #include "src/core/lib/iomgr/timer.h"
 #include "src/core/lib/iomgr/wakeup_fd_posix.h"
-#include "src/core/lib/iomgr/workqueue.h"
 #include "src/core/lib/profiling/timers.h"
 #include "src/core/lib/support/block_annotate.h"
 #include "src/core/lib/support/env.h"
@@ -73,9 +57,6 @@
 
 #define GRPC_POLLSET_KICK_BROADCAST ((grpc_pollset_worker *)1)
 
-/* Uncomment the following to enable extra checks on poll_object operations */
-/* #define PO_DEBUG */
-
 /* The maximum number of polling threads per polling island. By default no
    limit */
 static int g_max_pollers_per_pi = INT_MAX;
@@ -108,7 +89,7 @@ typedef enum {
 } poll_obj_type;
 
 typedef struct poll_obj {
-#ifdef PO_DEBUG
+#ifndef NDEBUG
   poll_obj_type obj_type;
 #endif
   gpr_mu mu;
@@ -163,8 +144,7 @@ struct grpc_fd {
 };
 
 /* Reference counting for fds */
-// #define GRPC_FD_REF_COUNT_DEBUG
-#ifdef GRPC_FD_REF_COUNT_DEBUG
+#ifndef NDEBUG
 static void fd_ref(grpc_fd *fd, const char *reason, const char *file, int line);
 static void fd_unref(grpc_fd *fd, const char *reason, const char *file,
                      int line);
@@ -184,18 +164,18 @@ static void fd_global_shutdown(void);
  * Polling island Declarations
  */
 
-#ifdef GRPC_WORKQUEUE_REFCOUNT_DEBUG
+#ifndef NDEBUG
 
 #define PI_ADD_REF(p, r) pi_add_ref_dbg((p), (r), __FILE__, __LINE__)
 #define PI_UNREF(exec_ctx, p, r) \
   pi_unref_dbg((exec_ctx), (p), (r), __FILE__, __LINE__)
 
-#else /* defined(GRPC_WORKQUEUE_REFCOUNT_DEBUG) */
+#else
 
 #define PI_ADD_REF(p, r) pi_add_ref((p))
 #define PI_UNREF(exec_ctx, p, r) pi_unref((exec_ctx), (p))
 
-#endif /* !defined(GRPC_PI_REF_COUNT_DEBUG) */
+#endif
 
 typedef struct worker_node {
   struct worker_node *next;
@@ -204,8 +184,6 @@ typedef struct worker_node {
 
 /* This is also used as grpc_workqueue (by directly casing it) */
 typedef struct polling_island {
-  grpc_closure_scheduler workqueue_scheduler;
-
   gpr_mu mu;
   /* Ref count. Use PI_ADD_REF() and PI_UNREF() macros to increment/decrement
      the refcount.
@@ -226,15 +204,6 @@ typedef struct polling_island {
 
   /* Number of threads currently polling on this island */
   gpr_atm poller_count;
-  /* Mutex guarding the read end of the workqueue (must be held to pop from
-   * workqueue_items) */
-  gpr_mu workqueue_read_mu;
-  /* Queue of closures to be executed */
-  gpr_mpscq workqueue_items;
-  /* Count of items in workqueue_items */
-  gpr_atm workqueue_item_count;
-  /* Wakeup fd used to wake pollers to check the contents of workqueue_items */
-  grpc_wakeup_fd workqueue_wakeup_fd;
 
   /* The list of workers waiting to do polling on this polling island */
   gpr_mu worker_list_mu;
@@ -323,8 +292,6 @@ static __thread polling_island *g_current_thread_polling_island;
 
 /* Forward declaration */
 static void polling_island_delete(grpc_exec_ctx *exec_ctx, polling_island *pi);
-static void workqueue_enqueue(grpc_exec_ctx *exec_ctx, grpc_closure *closure,
-                              grpc_error *error);
 
 #ifdef GRPC_TSAN
 /* Currently TSAN may incorrectly flag data races between epoll_ctl and
@@ -337,57 +304,30 @@ static void workqueue_enqueue(grpc_exec_ctx *exec_ctx, grpc_closure *closure,
 gpr_atm g_epoll_sync;
 #endif /* defined(GRPC_TSAN) */
 
-static const grpc_closure_scheduler_vtable workqueue_scheduler_vtable = {
-    workqueue_enqueue, workqueue_enqueue, "workqueue"};
-
 static void pi_add_ref(polling_island *pi);
 static void pi_unref(grpc_exec_ctx *exec_ctx, polling_island *pi);
 
-#ifdef GRPC_WORKQUEUE_REFCOUNT_DEBUG
+#ifndef NDEBUG
 static void pi_add_ref_dbg(polling_island *pi, const char *reason,
                            const char *file, int line) {
-  long old_cnt = gpr_atm_acq_load(&pi->ref_count);
+  if (GRPC_TRACER_ON(grpc_polling_trace)) {
+    gpr_atm old_cnt = gpr_atm_acq_load(&pi->ref_count);
+    gpr_log(GPR_DEBUG, "Add ref pi: %p, old:%" PRIdPTR " -> new:%" PRIdPTR
+                       " (%s) - (%s, %d)",
+            pi, old_cnt, old_cnt + 1, reason, file, line);
+  }
   pi_add_ref(pi);
-  gpr_log(GPR_DEBUG, "Add ref pi: %p, old: %ld -> new:%ld (%s) - (%s, %d)",
-          (void *)pi, old_cnt, old_cnt + 1, reason, file, line);
 }
 
 static void pi_unref_dbg(grpc_exec_ctx *exec_ctx, polling_island *pi,
                          const char *reason, const char *file, int line) {
-  long old_cnt = gpr_atm_acq_load(&pi->ref_count);
-  pi_unref(exec_ctx, pi);
-  gpr_log(GPR_DEBUG, "Unref pi: %p, old:%ld -> new:%ld (%s) - (%s, %d)",
-          (void *)pi, old_cnt, (old_cnt - 1), reason, file, line);
-}
-
-static grpc_workqueue *workqueue_ref(grpc_workqueue *workqueue,
-                                     const char *file, int line,
-                                     const char *reason) {
-  if (workqueue != NULL) {
-    pi_add_ref_dbg((polling_island *)workqueue, reason, file, line);
-  }
-  return workqueue;
-}
-
-static void workqueue_unref(grpc_exec_ctx *exec_ctx, grpc_workqueue *workqueue,
-                            const char *file, int line, const char *reason) {
-  if (workqueue != NULL) {
-    pi_unref_dbg(exec_ctx, (polling_island *)workqueue, reason, file, line);
-  }
-}
-#else
-static grpc_workqueue *workqueue_ref(grpc_workqueue *workqueue) {
-  if (workqueue != NULL) {
-    pi_add_ref((polling_island *)workqueue);
-  }
-  return workqueue;
-}
-
-static void workqueue_unref(grpc_exec_ctx *exec_ctx,
-                            grpc_workqueue *workqueue) {
-  if (workqueue != NULL) {
-    pi_unref(exec_ctx, (polling_island *)workqueue);
+  if (GRPC_TRACER_ON(grpc_polling_trace)) {
+    gpr_atm old_cnt = gpr_atm_acq_load(&pi->ref_count);
+    gpr_log(GPR_DEBUG, "Unref pi: %p, old:%" PRIdPTR " -> new:%" PRIdPTR
+                       " (%s) - (%s, %d)",
+            pi, old_cnt, (old_cnt - 1), reason, file, line);
   }
+  pi_unref(exec_ctx, pi);
 }
 #endif
 
@@ -592,17 +532,12 @@ static polling_island *polling_island_create(grpc_exec_ctx *exec_ctx,
   *error = GRPC_ERROR_NONE;
 
   pi = gpr_malloc(sizeof(*pi));
-  pi->workqueue_scheduler.vtable = &workqueue_scheduler_vtable;
   gpr_mu_init(&pi->mu);
   pi->fd_cnt = 0;
   pi->fd_capacity = 0;
   pi->fds = NULL;
   pi->epoll_fd = -1;
 
-  gpr_mu_init(&pi->workqueue_read_mu);
-  gpr_mpscq_init(&pi->workqueue_items);
-  gpr_atm_rel_store(&pi->workqueue_item_count, 0);
-
   gpr_atm_rel_store(&pi->ref_count, 0);
   gpr_atm_rel_store(&pi->poller_count, 0);
   gpr_atm_rel_store(&pi->merged_to, (gpr_atm)NULL);
@@ -610,11 +545,6 @@ static polling_island *polling_island_create(grpc_exec_ctx *exec_ctx,
   gpr_mu_init(&pi->worker_list_mu);
   worker_node_init(&pi->worker_list_head);
 
-  if (!append_error(error, grpc_wakeup_fd_init(&pi->workqueue_wakeup_fd),
-                    err_desc)) {
-    goto done;
-  }
-
   pi->epoll_fd = epoll_create1(EPOLL_CLOEXEC);
 
   if (pi->epoll_fd < 0) {
@@ -622,8 +552,6 @@ static polling_island *polling_island_create(grpc_exec_ctx *exec_ctx,
     goto done;
   }
 
-  polling_island_add_wakeup_fd_locked(pi, &pi->workqueue_wakeup_fd, error);
-
   if (initial_fd != NULL) {
     polling_island_add_fds_locked(pi, &initial_fd, 1, true, error);
   }
@@ -642,11 +570,7 @@ static void polling_island_delete(grpc_exec_ctx *exec_ctx, polling_island *pi) {
   if (pi->epoll_fd >= 0) {
     close(pi->epoll_fd);
   }
-  GPR_ASSERT(gpr_atm_no_barrier_load(&pi->workqueue_item_count) == 0);
-  gpr_mu_destroy(&pi->workqueue_read_mu);
-  gpr_mpscq_destroy(&pi->workqueue_items);
   gpr_mu_destroy(&pi->mu);
-  grpc_wakeup_fd_destroy(&pi->workqueue_wakeup_fd);
   gpr_mu_destroy(&pi->worker_list_mu);
   GPR_ASSERT(is_worker_node_detached(&pi->worker_list_head));
 
@@ -794,45 +718,6 @@ static void polling_island_unlock_pair(polling_island *p, polling_island *q) {
   }
 }
 
-static void workqueue_maybe_wakeup(polling_island *pi) {
-  /* If this thread is the current poller, then it may be that it's about to
-     decrement the current poller count, so we need to look past this thread */
-  bool is_current_poller = (g_current_thread_polling_island == pi);
-  gpr_atm min_current_pollers_for_wakeup = is_current_poller ? 1 : 0;
-  gpr_atm current_pollers = gpr_atm_no_barrier_load(&pi->poller_count);
-  /* Only issue a wakeup if it's likely that some poller could come in and take
-     it right now. Note that since we do an anticipatory mpscq_pop every poll
-     loop, it's ok if we miss the wakeup here, as we'll get the work item when
-     the next poller enters anyway. */
-  if (current_pollers > min_current_pollers_for_wakeup) {
-    GRPC_LOG_IF_ERROR("workqueue_wakeup_fd",
-                      grpc_wakeup_fd_wakeup(&pi->workqueue_wakeup_fd));
-  }
-}
-
-static void workqueue_move_items_to_parent(polling_island *q) {
-  polling_island *p = (polling_island *)gpr_atm_no_barrier_load(&q->merged_to);
-  if (p == NULL) {
-    return;
-  }
-  gpr_mu_lock(&q->workqueue_read_mu);
-  int num_added = 0;
-  while (gpr_atm_no_barrier_load(&q->workqueue_item_count) > 0) {
-    gpr_mpscq_node *n = gpr_mpscq_pop(&q->workqueue_items);
-    if (n != NULL) {
-      gpr_atm_no_barrier_fetch_add(&q->workqueue_item_count, -1);
-      gpr_atm_no_barrier_fetch_add(&p->workqueue_item_count, 1);
-      gpr_mpscq_push(&p->workqueue_items, n);
-      num_added++;
-    }
-  }
-  gpr_mu_unlock(&q->workqueue_read_mu);
-  if (num_added > 0) {
-    workqueue_maybe_wakeup(p);
-  }
-  workqueue_move_items_to_parent(p);
-}
-
 static polling_island *polling_island_merge(polling_island *p,
                                             polling_island *q,
                                             grpc_error **error) {
@@ -857,8 +742,6 @@ static polling_island *polling_island_merge(polling_island *p,
     /* Add the 'merged_to' link from p --> q */
     gpr_atm_rel_store(&p->merged_to, (gpr_atm)q);
     PI_ADD_REF(q, "pi_merge"); /* To account for the new incoming ref from p */
-
-    workqueue_move_items_to_parent(p);
   }
   /* else if p == q, nothing needs to be done */
 
@@ -869,32 +752,6 @@ static polling_island *polling_island_merge(polling_island *p,
   return q;
 }
 
-static void workqueue_enqueue(grpc_exec_ctx *exec_ctx, grpc_closure *closure,
-                              grpc_error *error) {
-  GPR_TIMER_BEGIN("workqueue.enqueue", 0);
-  grpc_workqueue *workqueue = (grpc_workqueue *)closure->scheduler;
-  /* take a ref to the workqueue: otherwise it can happen that whatever events
-   * this kicks off ends up destroying the workqueue before this function
-   * completes */
-  GRPC_WORKQUEUE_REF(workqueue, "enqueue");
-  polling_island *pi = (polling_island *)workqueue;
-  gpr_atm last = gpr_atm_no_barrier_fetch_add(&pi->workqueue_item_count, 1);
-  closure->error_data.error = error;
-  gpr_mpscq_push(&pi->workqueue_items, &closure->next_data.atm_next);
-  if (last == 0) {
-    workqueue_maybe_wakeup(pi);
-  }
-  workqueue_move_items_to_parent(pi);
-  GRPC_WORKQUEUE_UNREF(exec_ctx, workqueue, "enqueue");
-  GPR_TIMER_END("workqueue.enqueue", 0);
-}
-
-static grpc_closure_scheduler *workqueue_scheduler(grpc_workqueue *workqueue) {
-  polling_island *pi = (polling_island *)workqueue;
-  return workqueue == NULL ? grpc_schedule_on_exec_ctx
-                           : &pi->workqueue_scheduler;
-}
-
 static grpc_error *polling_island_global_init() {
   grpc_error *error = GRPC_ERROR_NONE;
 
@@ -935,14 +792,17 @@ static void polling_island_global_shutdown() {
 static grpc_fd *fd_freelist = NULL;
 static gpr_mu fd_freelist_mu;
 
-#ifdef GRPC_FD_REF_COUNT_DEBUG
+#ifndef NDEBUG
 #define REF_BY(fd, n, reason) ref_by(fd, n, reason, __FILE__, __LINE__)
 #define UNREF_BY(fd, n, reason) unref_by(fd, n, reason, __FILE__, __LINE__)
 static void ref_by(grpc_fd *fd, int n, const char *reason, const char *file,
                    int line) {
-  gpr_log(GPR_DEBUG, "FD %d %p   ref %d %ld -> %ld [%s; %s:%d]", fd->fd,
-          (void *)fd, n, gpr_atm_no_barrier_load(&fd->refst),
-          gpr_atm_no_barrier_load(&fd->refst) + n, reason, file, line);
+  if (GRPC_TRACER_ON(grpc_trace_fd_refcount)) {
+    gpr_log(GPR_DEBUG,
+            "FD %d %p   ref %d %" PRIdPTR " -> %" PRIdPTR " [%s; %s:%d]",
+            fd->fd, fd, n, gpr_atm_no_barrier_load(&fd->refst),
+            gpr_atm_no_barrier_load(&fd->refst) + n, reason, file, line);
+  }
 #else
 #define REF_BY(fd, n, reason) ref_by(fd, n)
 #define UNREF_BY(fd, n, reason) unref_by(fd, n)
@@ -951,18 +811,19 @@ static void ref_by(grpc_fd *fd, int n) {
   GPR_ASSERT(gpr_atm_no_barrier_fetch_add(&fd->refst, n) > 0);
 }
 
-#ifdef GRPC_FD_REF_COUNT_DEBUG
+#ifndef NDEBUG
 static void unref_by(grpc_fd *fd, int n, const char *reason, const char *file,
                      int line) {
-  gpr_atm old;
-  gpr_log(GPR_DEBUG, "FD %d %p unref %d %ld -> %ld [%s; %s:%d]", fd->fd,
-          (void *)fd, n, gpr_atm_no_barrier_load(&fd->refst),
-          gpr_atm_no_barrier_load(&fd->refst) - n, reason, file, line);
+  if (GRPC_TRACER_ON(grpc_trace_fd_refcount)) {
+    gpr_log(GPR_DEBUG,
+            "FD %d %p unref %d %" PRIdPTR " -> %" PRIdPTR " [%s; %s:%d]",
+            fd->fd, fd, n, gpr_atm_no_barrier_load(&fd->refst),
+            gpr_atm_no_barrier_load(&fd->refst) - n, reason, file, line);
+  }
 #else
 static void unref_by(grpc_fd *fd, int n) {
-  gpr_atm old;
 #endif
-  old = gpr_atm_full_fetch_add(&fd->refst, -n);
+  gpr_atm old = gpr_atm_full_fetch_add(&fd->refst, -n);
   if (old == n) {
     /* Add the fd to the freelist */
     gpr_mu_lock(&fd_freelist_mu);
@@ -980,7 +841,7 @@ static void unref_by(grpc_fd *fd, int n) {
 }
 
 /* Increment refcount by two to avoid changing the orphan bit */
-#ifdef GRPC_FD_REF_COUNT_DEBUG
+#ifndef NDEBUG
 static void fd_ref(grpc_fd *fd, const char *reason, const char *file,
                    int line) {
   ref_by(fd, 2, reason, file, line);
@@ -1029,7 +890,7 @@ static grpc_fd *fd_create(int fd, const char *name) {
    * would be holding a lock to it anyway. */
   gpr_mu_lock(&new_fd->po.mu);
   new_fd->po.pi = NULL;
-#ifdef PO_DEBUG
+#ifndef NDEBUG
   new_fd->po.obj_type = POLL_OBJ_FD;
 #endif
 
@@ -1048,8 +909,10 @@ static grpc_fd *fd_create(int fd, const char *name) {
   char *fd_name;
   gpr_asprintf(&fd_name, "%s fd=%d", name, fd);
   grpc_iomgr_register_object(&new_fd->iomgr_object, fd_name);
-#ifdef GRPC_FD_REF_COUNT_DEBUG
-  gpr_log(GPR_DEBUG, "FD %d %p create %s", fd, (void *)new_fd, fd_name);
+#ifndef NDEBUG
+  if (GRPC_TRACER_ON(grpc_trace_fd_refcount)) {
+    gpr_log(GPR_DEBUG, "FD %d %p create %s", fd, new_fd, fd_name);
+  }
 #endif
   gpr_free(fd_name);
   return new_fd;
@@ -1108,7 +971,7 @@ static void fd_orphan(grpc_exec_ctx *exec_ctx, grpc_fd *fd,
     fd->po.pi = NULL;
   }
 
-  grpc_closure_sched(exec_ctx, fd->on_done_closure, GRPC_ERROR_REF(error));
+  GRPC_CLOSURE_SCHED(exec_ctx, fd->on_done_closure, GRPC_ERROR_REF(error));
 
   gpr_mu_unlock(&fd->po.mu);
   UNREF_BY(fd, 2, reason); /* Drop the reference */
@@ -1153,14 +1016,6 @@ static void fd_notify_on_write(grpc_exec_ctx *exec_ctx, grpc_fd *fd,
   grpc_lfev_notify_on(exec_ctx, &fd->write_closure, closure);
 }
 
-static grpc_workqueue *fd_get_workqueue(grpc_fd *fd) {
-  gpr_mu_lock(&fd->po.mu);
-  grpc_workqueue *workqueue =
-      GRPC_WORKQUEUE_REF((grpc_workqueue *)fd->po.pi, "fd_get_workqueue");
-  gpr_mu_unlock(&fd->po.mu);
-  return workqueue;
-}
-
 /*******************************************************************************
  * Pollset Definitions
  */
@@ -1313,7 +1168,7 @@ static void pollset_init(grpc_pollset *pollset, gpr_mu **mu) {
   gpr_mu_init(&pollset->po.mu);
   *mu = &pollset->po.mu;
   pollset->po.pi = NULL;
-#ifdef PO_DEBUG
+#ifndef NDEBUG
   pollset->po.obj_type = POLL_OBJ_POLLSET;
 #endif
 
@@ -1401,7 +1256,7 @@ static void finish_shutdown_locked(grpc_exec_ctx *exec_ctx,
 
   /* Release the ref and set pollset->po.pi to NULL */
   pollset_release_polling_island(exec_ctx, pollset, "ps_shutdown");
-  grpc_closure_sched(exec_ctx, pollset->shutdown_done, GRPC_ERROR_NONE);
+  GRPC_CLOSURE_SCHED(exec_ctx, pollset->shutdown_done, GRPC_ERROR_NONE);
 }
 
 /* pollset->po.mu lock must be held by the caller before calling this */
@@ -1432,33 +1287,6 @@ static void pollset_destroy(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset) {
   gpr_mu_destroy(&pollset->po.mu);
 }
 
-static bool maybe_do_workqueue_work(grpc_exec_ctx *exec_ctx,
-                                    polling_island *pi) {
-  if (gpr_mu_trylock(&pi->workqueue_read_mu)) {
-    gpr_mpscq_node *n = gpr_mpscq_pop(&pi->workqueue_items);
-    gpr_mu_unlock(&pi->workqueue_read_mu);
-    if (n != NULL) {
-      if (gpr_atm_full_fetch_add(&pi->workqueue_item_count, -1) > 1) {
-        workqueue_maybe_wakeup(pi);
-      }
-      grpc_closure *c = (grpc_closure *)n;
-      grpc_error *error = c->error_data.error;
-#ifndef NDEBUG
-      c->scheduled = false;
-#endif
-      c->cb(exec_ctx, c->cb_arg, error);
-      GRPC_ERROR_UNREF(error);
-      return true;
-    } else if (gpr_atm_no_barrier_load(&pi->workqueue_item_count) > 0) {
-      /* n == NULL might mean there's work but it's not available to be popped
-       * yet - try to ensure another workqueue wakes up to check shortly if so
-       */
-      workqueue_maybe_wakeup(pi);
-    }
-  }
-  return false;
-}
-
 /* NOTE: This function may modify 'now' */
 static bool acquire_polling_lease(grpc_pollset_worker *worker,
                                   polling_island *pi, gpr_timespec deadline,
@@ -1594,12 +1422,7 @@ static void pollset_do_epoll_pwait(grpc_exec_ctx *exec_ctx, int epoll_fd,
 
   for (int i = 0; i < ep_rv; ++i) {
     void *data_ptr = ep_ev[i].data.ptr;
-    if (data_ptr == &pi->workqueue_wakeup_fd) {
-      append_error(error,
-                   grpc_wakeup_fd_consume_wakeup(&pi->workqueue_wakeup_fd),
-                   err_desc);
-      maybe_do_workqueue_work(exec_ctx, pi);
-    } else if (data_ptr == &polling_island_wakeup_fd) {
+    if (data_ptr == &polling_island_wakeup_fd) {
       GRPC_POLLING_TRACE(
           "pollset_work: pollset: %p, worker: %p polling island (epoll_fd: "
           "%d) got merged",
@@ -1675,15 +1498,10 @@ static void pollset_work_and_unlock(grpc_exec_ctx *exec_ctx,
   PI_ADD_REF(pi, "ps_work");
   gpr_mu_unlock(&pollset->po.mu);
 
-  /* If we get some workqueue work to do, it might end up completing an item on
-     the completion queue, so there's no need to poll... so we skip that and
-     redo the complete loop to verify */
-  if (!maybe_do_workqueue_work(exec_ctx, pi)) {
-    g_current_thread_polling_island = pi;
-    pollset_do_epoll_pwait(exec_ctx, epoll_fd, pollset, pi, worker, now,
-                           deadline, sig_mask, error);
-    g_current_thread_polling_island = NULL;
-  }
+  g_current_thread_polling_island = pi;
+  pollset_do_epoll_pwait(exec_ctx, epoll_fd, pollset, pi, worker, now, deadline,
+                         sig_mask, error);
+  g_current_thread_polling_island = NULL;
 
   GPR_ASSERT(pi != NULL);
 
@@ -1804,7 +1622,7 @@ static void add_poll_object(grpc_exec_ctx *exec_ctx, poll_obj *bag,
                             poll_obj_type item_type) {
   GPR_TIMER_BEGIN("add_poll_object", 0);
 
-#ifdef PO_DEBUG
+#ifndef NDEBUG
   GPR_ASSERT(item->obj_type == item_type);
   GPR_ASSERT(bag->obj_type == bag_type);
 #endif
@@ -1963,7 +1781,7 @@ static grpc_pollset_set *pollset_set_create(void) {
   grpc_pollset_set *pss = gpr_malloc(sizeof(*pss));
   gpr_mu_init(&pss->po.mu);
   pss->po.pi = NULL;
-#ifdef PO_DEBUG
+#ifndef NDEBUG
   pss->po.obj_type = POLL_OBJ_POLLSET_SET;
 #endif
   return pss;
@@ -2036,7 +1854,6 @@ static const grpc_event_engine_vtable vtable = {
     .fd_notify_on_read = fd_notify_on_read,
     .fd_notify_on_write = fd_notify_on_write,
     .fd_get_read_notifier_pollset = fd_get_read_notifier_pollset,
-    .fd_get_workqueue = fd_get_workqueue,
 
     .pollset_init = pollset_init,
     .pollset_shutdown = pollset_shutdown,
@@ -2054,10 +1871,6 @@ static const grpc_event_engine_vtable vtable = {
     .pollset_set_add_fd = pollset_set_add_fd,
     .pollset_set_del_fd = pollset_set_del_fd,
 
-    .workqueue_ref = workqueue_ref,
-    .workqueue_unref = workqueue_unref,
-    .workqueue_scheduler = workqueue_scheduler,
-
     .shutdown_engine = shutdown_engine,
 };
 
diff --git a/src/core/lib/iomgr/ev_epoll_limited_pollers_linux.h b/src/core/lib/iomgr/ev_epoll_limited_pollers_linux.h
index 379e1ded3b..1d6af5f52c 100644
--- a/src/core/lib/iomgr/ev_epoll_limited_pollers_linux.h
+++ b/src/core/lib/iomgr/ev_epoll_limited_pollers_linux.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/ev_epoll_thread_pool_linux.c b/src/core/lib/iomgr/ev_epoll_thread_pool_linux.c
index bb44321922..49be72c03e 100644
--- a/src/core/lib/iomgr/ev_epoll_thread_pool_linux.c
+++ b/src/core/lib/iomgr/ev_epoll_thread_pool_linux.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2017, Google Inc.
- * All rights reserved.
+ * Copyright 2017 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -61,7 +46,6 @@
 #include "src/core/lib/iomgr/lockfree_event.h"
 #include "src/core/lib/iomgr/timer.h"
 #include "src/core/lib/iomgr/wakeup_fd_posix.h"
-#include "src/core/lib/iomgr/workqueue.h"
 #include "src/core/lib/profiling/timers.h"
 #include "src/core/lib/support/block_annotate.h"
 
@@ -109,23 +93,20 @@ static void fd_global_shutdown(void);
  * epoll set Declarations
  */
 
-#ifdef GRPC_WORKQUEUE_REFCOUNT_DEBUG
+#ifndef NDEBUG
 
 #define EPS_ADD_REF(p, r) eps_add_ref_dbg((p), (r), __FILE__, __LINE__)
 #define EPS_UNREF(exec_ctx, p, r) \
   eps_unref_dbg((exec_ctx), (p), (r), __FILE__, __LINE__)
 
-#else /* defined(GRPC_WORKQUEUE_REFCOUNT_DEBUG) */
+#else
 
 #define EPS_ADD_REF(p, r) eps_add_ref((p))
 #define EPS_UNREF(exec_ctx, p, r) eps_unref((exec_ctx), (p))
 
-#endif /* !defined(GRPC_EPS_REF_COUNT_DEBUG) */
+#endif
 
-/* This is also used as grpc_workqueue (by directly casting it) */
 typedef struct epoll_set {
-  grpc_closure_scheduler workqueue_scheduler;
-
   /* Mutex poller should acquire to poll this. This enforces that only one
    * poller can be polling on epoll_set at any time */
   gpr_mu mu;
@@ -139,15 +120,6 @@ typedef struct epoll_set {
 
   /* Number of threads currently polling on this epoll set*/
   gpr_atm poller_count;
-  /* Mutex guarding the read end of the workqueue (must be held to pop from
-   * workqueue_items) */
-  gpr_mu workqueue_read_mu;
-  /* Queue of closures to be executed */
-  gpr_mpscq workqueue_items;
-  /* Count of items in workqueue_items */
-  gpr_atm workqueue_item_count;
-  /* Wakeup fd used to wake pollers to check the contents of workqueue_items */
-  grpc_wakeup_fd workqueue_wakeup_fd;
 
   /* Is the epoll set shutdown */
   gpr_atm is_shutdown;
@@ -181,7 +153,9 @@ struct grpc_pollset {
 /*******************************************************************************
  * Pollset-set Declarations
  */
-struct grpc_pollset_set {};
+struct grpc_pollset_set {
+  char unused;
+};
 
 /*****************************************************************************
  * Dedicated polling threads and pollsets - Declarations
@@ -235,8 +209,6 @@ static __thread epoll_set *g_current_thread_epoll_set;
 
 /* Forward declaration */
 static void epoll_set_delete(epoll_set *eps);
-static void workqueue_enqueue(grpc_exec_ctx *exec_ctx, grpc_closure *closure,
-                              grpc_error *error);
 
 #ifdef GRPC_TSAN
 /* Currently TSAN may incorrectly flag data races between epoll_ctl and
@@ -249,57 +221,30 @@ static void workqueue_enqueue(grpc_exec_ctx *exec_ctx, grpc_closure *closure,
 gpr_atm g_epoll_sync;
 #endif /* defined(GRPC_TSAN) */
 
-static const grpc_closure_scheduler_vtable workqueue_scheduler_vtable = {
-    workqueue_enqueue, workqueue_enqueue, "workqueue"};
-
 static void eps_add_ref(epoll_set *eps);
 static void eps_unref(grpc_exec_ctx *exec_ctx, epoll_set *eps);
 
-#ifdef GRPC_WORKQUEUE_REFCOUNT_DEBUG
+#ifndef NDEBUG
 static void eps_add_ref_dbg(epoll_set *eps, const char *reason,
                             const char *file, int line) {
-  long old_cnt = gpr_atm_acq_load(&eps->ref_count);
+  if (GRPC_TRACER_ON(grpc_polling_trace)) {
+    gpr_atm old_cnt = gpr_atm_acq_load(&eps->ref_count);
+    gpr_log(GPR_DEBUG, "Add ref eps: %p, old:%" PRIdPTR " -> new:%" PRIdPTR
+                       " (%s) - (%s, %d)",
+            eps, old_cnt, old_cnt + 1, reason, file, line);
+  }
   eps_add_ref(eps);
-  gpr_log(GPR_DEBUG, "Add ref eps: %p, old: %ld -> new:%ld (%s) - (%s, %d)",
-          (void *)eps, old_cnt, old_cnt + 1, reason, file, line);
 }
 
 static void eps_unref_dbg(grpc_exec_ctx *exec_ctx, epoll_set *eps,
                           const char *reason, const char *file, int line) {
-  long old_cnt = gpr_atm_acq_load(&eps->ref_count);
-  eps_unref(exec_ctx, eps);
-  gpr_log(GPR_DEBUG, "Unref eps: %p, old:%ld -> new:%ld (%s) - (%s, %d)",
-          (void *)eps, old_cnt, (old_cnt - 1), reason, file, line);
-}
-
-static grpc_workqueue *workqueue_ref(grpc_workqueue *workqueue,
-                                     const char *file, int line,
-                                     const char *reason) {
-  if (workqueue != NULL) {
-    eps_add_ref_dbg((epoll_set *)workqueue, reason, file, line);
-  }
-  return workqueue;
-}
-
-static void workqueue_unref(grpc_exec_ctx *exec_ctx, grpc_workqueue *workqueue,
-                            const char *file, int line, const char *reason) {
-  if (workqueue != NULL) {
-    eps_unref_dbg(exec_ctx, (epoll_set *)workqueue, reason, file, line);
-  }
-}
-#else
-static grpc_workqueue *workqueue_ref(grpc_workqueue *workqueue) {
-  if (workqueue != NULL) {
-    eps_add_ref((epoll_set *)workqueue);
-  }
-  return workqueue;
-}
-
-static void workqueue_unref(grpc_exec_ctx *exec_ctx,
-                            grpc_workqueue *workqueue) {
-  if (workqueue != NULL) {
-    eps_unref(exec_ctx, (epoll_set *)workqueue);
+  if (GRPC_TRACER_ON(grpc_polling_trace)) {
+    gpr_atm old_cnt = gpr_atm_acq_load(&eps->ref_count);
+    gpr_log(GPR_DEBUG, "Unref eps: %p, old:%" PRIdPTR " -> new:%" PRIdPTR
+                       " (%s) - (%s, %d)",
+            eps, old_cnt, (old_cnt - 1), reason, file, line);
   }
+  eps_unref(exec_ctx, eps);
 }
 #endif
 
@@ -394,24 +339,15 @@ static epoll_set *epoll_set_create(grpc_error **error) {
   *error = GRPC_ERROR_NONE;
 
   eps = gpr_malloc(sizeof(*eps));
-  eps->workqueue_scheduler.vtable = &workqueue_scheduler_vtable;
   eps->epoll_fd = -1;
 
   gpr_mu_init(&eps->mu);
-  gpr_mu_init(&eps->workqueue_read_mu);
-  gpr_mpscq_init(&eps->workqueue_items);
-  gpr_atm_rel_store(&eps->workqueue_item_count, 0);
 
   gpr_atm_rel_store(&eps->ref_count, 0);
   gpr_atm_rel_store(&eps->poller_count, 0);
 
   gpr_atm_rel_store(&eps->is_shutdown, false);
 
-  if (!append_error(error, grpc_wakeup_fd_init(&eps->workqueue_wakeup_fd),
-                    err_desc)) {
-    goto done;
-  }
-
   eps->epoll_fd = epoll_create1(EPOLL_CLOEXEC);
 
   if (eps->epoll_fd < 0) {
@@ -419,8 +355,6 @@ static epoll_set *epoll_set_create(grpc_error **error) {
     goto done;
   }
 
-  epoll_set_add_wakeup_fd_locked(eps, &eps->workqueue_wakeup_fd, error);
-
 done:
   if (*error != GRPC_ERROR_NONE) {
     epoll_set_delete(eps);
@@ -434,57 +368,11 @@ static void epoll_set_delete(epoll_set *eps) {
     close(eps->epoll_fd);
   }
 
-  GPR_ASSERT(gpr_atm_no_barrier_load(&eps->workqueue_item_count) == 0);
   gpr_mu_destroy(&eps->mu);
-  gpr_mu_destroy(&eps->workqueue_read_mu);
-  gpr_mpscq_destroy(&eps->workqueue_items);
-  grpc_wakeup_fd_destroy(&eps->workqueue_wakeup_fd);
 
   gpr_free(eps);
 }
 
-static void workqueue_maybe_wakeup(epoll_set *eps) {
-  /* If this thread is the current poller, then it may be that it's about to
-     decrement the current poller count, so we need to look past this thread */
-  bool is_current_poller = (g_current_thread_epoll_set == eps);
-  gpr_atm min_current_pollers_for_wakeup = is_current_poller ? 1 : 0;
-  gpr_atm current_pollers = gpr_atm_no_barrier_load(&eps->poller_count);
-  /* Only issue a wakeup if it's likely that some poller could come in and take
-     it right now. Note that since we do an anticipatory mpscq_pop every poll
-     loop, it's ok if we miss the wakeup here, as we'll get the work item when
-     the next poller enters anyway. */
-  if (current_pollers > min_current_pollers_for_wakeup) {
-    GRPC_LOG_IF_ERROR("workqueue_wakeup_fd",
-                      grpc_wakeup_fd_wakeup(&eps->workqueue_wakeup_fd));
-  }
-}
-
-static void workqueue_enqueue(grpc_exec_ctx *exec_ctx, grpc_closure *closure,
-                              grpc_error *error) {
-  GPR_TIMER_BEGIN("workqueue.enqueue", 0);
-  grpc_workqueue *workqueue = (grpc_workqueue *)closure->scheduler;
-  /* take a ref to the workqueue: otherwise it can happen that whatever events
-   * this kicks off ends up destroying the workqueue before this function
-   * completes */
-  GRPC_WORKQUEUE_REF(workqueue, "enqueue");
-  epoll_set *eps = (epoll_set *)workqueue;
-  gpr_atm last = gpr_atm_no_barrier_fetch_add(&eps->workqueue_item_count, 1);
-  closure->error_data.error = error;
-  gpr_mpscq_push(&eps->workqueue_items, &closure->next_data.atm_next);
-  if (last == 0) {
-    workqueue_maybe_wakeup(eps);
-  }
-
-  GRPC_WORKQUEUE_UNREF(exec_ctx, workqueue, "enqueue");
-  GPR_TIMER_END("workqueue.enqueue", 0);
-}
-
-static grpc_closure_scheduler *workqueue_scheduler(grpc_workqueue *workqueue) {
-  epoll_set *eps = (epoll_set *)workqueue;
-  return workqueue == NULL ? grpc_schedule_on_exec_ctx
-                           : &eps->workqueue_scheduler;
-}
-
 static grpc_error *epoll_set_global_init() {
   grpc_error *error = GRPC_ERROR_NONE;
 
@@ -631,7 +519,7 @@ static void fd_orphan(grpc_exec_ctx *exec_ctx, grpc_fd *fd,
     fd->eps = NULL;
   }
 
-  grpc_closure_sched(exec_ctx, fd->on_done_closure, GRPC_ERROR_REF(error));
+  GRPC_CLOSURE_SCHED(exec_ctx, fd->on_done_closure, GRPC_ERROR_REF(error));
 
   gpr_mu_unlock(&fd->mu);
 
@@ -680,8 +568,6 @@ static void fd_notify_on_write(grpc_exec_ctx *exec_ctx, grpc_fd *fd,
   grpc_lfev_notify_on(exec_ctx, &fd->write_closure, closure);
 }
 
-static grpc_workqueue *fd_get_workqueue(grpc_fd *fd) { return NULL; }
-
 /*******************************************************************************
  * Pollset Definitions
  */
@@ -834,7 +720,7 @@ static void finish_shutdown_locked(grpc_exec_ctx *exec_ctx,
 
   /* Release the ref and set pollset->eps to NULL */
   pollset_release_epoll_set(exec_ctx, pollset, "ps_shutdown");
-  grpc_closure_sched(exec_ctx, pollset->shutdown_done, GRPC_ERROR_NONE);
+  GRPC_CLOSURE_SCHED(exec_ctx, pollset->shutdown_done, GRPC_ERROR_NONE);
 }
 
 /* pollset->mu lock must be held by the caller before calling this */
@@ -865,32 +751,6 @@ static void pollset_destroy(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset) {
   gpr_mu_destroy(&pollset->mu);
 }
 
-static bool maybe_do_workqueue_work(grpc_exec_ctx *exec_ctx, epoll_set *eps) {
-  if (gpr_mu_trylock(&eps->workqueue_read_mu)) {
-    gpr_mpscq_node *n = gpr_mpscq_pop(&eps->workqueue_items);
-    gpr_mu_unlock(&eps->workqueue_read_mu);
-    if (n != NULL) {
-      if (gpr_atm_full_fetch_add(&eps->workqueue_item_count, -1) > 1) {
-        workqueue_maybe_wakeup(eps);
-      }
-      grpc_closure *c = (grpc_closure *)n;
-      grpc_error *error = c->error_data.error;
-#ifndef NDEBUG
-      c->scheduled = false;
-#endif
-      c->cb(exec_ctx, c->cb_arg, error);
-      GRPC_ERROR_UNREF(error);
-      return true;
-    } else if (gpr_atm_no_barrier_load(&eps->workqueue_item_count) > 0) {
-      /* n == NULL might mean there's work but it's not available to be popped
-       * yet - try to ensure another workqueue wakes up to check shortly if so
-       */
-      workqueue_maybe_wakeup(eps);
-    }
-  }
-  return false;
-}
-
 /* Blocking call */
 static void acquire_epoll_lease(epoll_set *eps) {
   if (g_num_threads_per_eps > 1) {
@@ -934,12 +794,7 @@ static void do_epoll_wait(grpc_exec_ctx *exec_ctx, int epoll_fd, epoll_set *eps,
 
   for (int i = 0; i < ep_rv; ++i) {
     void *data_ptr = ep_ev[i].data.ptr;
-    if (data_ptr == &eps->workqueue_wakeup_fd) {
-      append_error(error,
-                   grpc_wakeup_fd_consume_wakeup(&eps->workqueue_wakeup_fd),
-                   err_desc);
-      maybe_do_workqueue_work(exec_ctx, eps);
-    } else if (data_ptr == &epoll_set_wakeup_fd) {
+    if (data_ptr == &epoll_set_wakeup_fd) {
       gpr_atm_rel_store(&eps->is_shutdown, 1);
       gpr_log(GPR_INFO, "pollset poller: shutdown set");
     } else {
@@ -966,18 +821,13 @@ static void epoll_set_work(grpc_exec_ctx *exec_ctx, epoll_set *eps,
      epoll set. */
   epoll_fd = eps->epoll_fd;
 
-  /* If we get some workqueue work to do, it might end up completing an item on
-     the completion queue, so there's no need to poll... so we skip that and
-     redo the complete loop to verify */
-  if (!maybe_do_workqueue_work(exec_ctx, eps)) {
-    gpr_atm_no_barrier_fetch_add(&eps->poller_count, 1);
-    g_current_thread_epoll_set = eps;
+  gpr_atm_no_barrier_fetch_add(&eps->poller_count, 1);
+  g_current_thread_epoll_set = eps;
 
-    do_epoll_wait(exec_ctx, epoll_fd, eps, error);
+  do_epoll_wait(exec_ctx, epoll_fd, eps, error);
 
-    g_current_thread_epoll_set = NULL;
-    gpr_atm_no_barrier_fetch_add(&eps->poller_count, -1);
-  }
+  g_current_thread_epoll_set = NULL;
+  gpr_atm_no_barrier_fetch_add(&eps->poller_count, -1);
 
   GPR_TIMER_END("epoll_set_work", 0);
 }
@@ -1120,7 +970,6 @@ static const grpc_event_engine_vtable vtable = {
     .fd_notify_on_read = fd_notify_on_read,
     .fd_notify_on_write = fd_notify_on_write,
     .fd_get_read_notifier_pollset = fd_get_read_notifier_pollset,
-    .fd_get_workqueue = fd_get_workqueue,
 
     .pollset_init = pollset_init,
     .pollset_shutdown = pollset_shutdown,
@@ -1138,10 +987,6 @@ static const grpc_event_engine_vtable vtable = {
     .pollset_set_add_fd = pollset_set_add_fd,
     .pollset_set_del_fd = pollset_set_del_fd,
 
-    .workqueue_ref = workqueue_ref,
-    .workqueue_unref = workqueue_unref,
-    .workqueue_scheduler = workqueue_scheduler,
-
     .shutdown_engine = shutdown_engine,
 };
 
diff --git a/src/core/lib/iomgr/ev_epoll_thread_pool_linux.h b/src/core/lib/iomgr/ev_epoll_thread_pool_linux.h
index 9af776a52e..2ca68cc9d1 100644
--- a/src/core/lib/iomgr/ev_epoll_thread_pool_linux.h
+++ b/src/core/lib/iomgr/ev_epoll_thread_pool_linux.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2017, Google Inc.
- * All rights reserved.
+ * Copyright 2017 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/ev_epollex_linux.c b/src/core/lib/iomgr/ev_epollex_linux.c
index 7cb6085e25..5690431759 100644
--- a/src/core/lib/iomgr/ev_epollex_linux.c
+++ b/src/core/lib/iomgr/ev_epollex_linux.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2017, Google Inc.
- * All rights reserved.
+ * Copyright 2017 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -59,7 +44,6 @@
 #include "src/core/lib/iomgr/sys_epoll_wrapper.h"
 #include "src/core/lib/iomgr/timer.h"
 #include "src/core/lib/iomgr/wakeup_fd_posix.h"
-#include "src/core/lib/iomgr/workqueue.h"
 #include "src/core/lib/profiling/timers.h"
 #include "src/core/lib/support/block_annotate.h"
 #include "src/core/lib/support/spinlock.h"
@@ -119,6 +103,32 @@ typedef struct pollable {
   grpc_pollset_worker *root_worker;
 } pollable;
 
+static const char *polling_obj_type_string(polling_obj_type t) {
+  switch (t) {
+    case PO_POLLING_GROUP:
+      return "polling_group";
+    case PO_POLLSET_SET:
+      return "pollset_set";
+    case PO_POLLSET:
+      return "pollset";
+    case PO_FD:
+      return "fd";
+    case PO_EMPTY_POLLABLE:
+      return "empty_pollable";
+    case PO_COUNT:
+      return "<invalid:count>";
+  }
+  return "<invalid>";
+}
+
+static char *pollable_desc(pollable *p) {
+  char *out;
+  gpr_asprintf(&out, "type=%s group=%p epfd=%d wakeup=%d",
+               polling_obj_type_string(p->po.type), p->po.group, p->epfd,
+               p->wakeup.read_fd);
+  return out;
+}
+
 static pollable g_empty_pollable;
 
 static void pollable_init(pollable *p, polling_obj_type type);
@@ -139,17 +149,6 @@ struct grpc_fd {
      Ref/Unref by two to avoid altering the orphaned bit */
   gpr_atm refst;
 
-  /* Wakeup fd used to wake pollers to check the contents of workqueue_items */
-  grpc_wakeup_fd workqueue_wakeup_fd;
-  grpc_closure_scheduler workqueue_scheduler;
-  /* Spinlock guarding the read end of the workqueue (must be held to pop from
-   * workqueue_items) */
-  gpr_spinlock workqueue_read_mu;
-  /* Queue of closures to be executed */
-  gpr_mpscq workqueue_items;
-  /* Count of items in workqueue_items */
-  gpr_atm workqueue_item_count;
-
   /* The fd is either closed or we relinquished control of it. In either
      cases, this indicates that the 'fd' on this structure is no longer
      valid */
@@ -172,12 +171,6 @@ struct grpc_fd {
 static void fd_global_init(void);
 static void fd_global_shutdown(void);
 
-static void workqueue_enqueue(grpc_exec_ctx *exec_ctx, grpc_closure *closure,
-                              grpc_error *error);
-
-static const grpc_closure_scheduler_vtable workqueue_scheduler_vtable = {
-    workqueue_enqueue, workqueue_enqueue, "workqueue"};
-
 /*******************************************************************************
  * Pollset Declarations
  */
@@ -202,12 +195,20 @@ struct grpc_pollset_worker {
   pollable *pollable;
 };
 
+#define MAX_EPOLL_EVENTS 100
+#define MAX_EPOLL_EVENTS_HANDLED_EACH_POLL_CALL 5
+
 struct grpc_pollset {
   pollable pollable;
   pollable *current_pollable;
+  int kick_alls_pending;
   bool kicked_without_poller;
   grpc_closure *shutdown_closure;
   grpc_pollset_worker *root_worker;
+
+  int event_cursor;
+  int event_count;
+  struct epoll_event events[MAX_EPOLL_EVENTS];
 };
 
 /*******************************************************************************
@@ -256,15 +257,18 @@ static bool append_error(grpc_error **composite, grpc_error *error,
 static grpc_fd *fd_freelist = NULL;
 static gpr_mu fd_freelist_mu;
 
-#ifdef GRPC_FD_REF_COUNT_DEBUG
+#ifndef NDEBUG
 #define REF_BY(fd, n, reason) ref_by(fd, n, reason, __FILE__, __LINE__)
 #define UNREF_BY(ec, fd, n, reason) \
   unref_by(ec, fd, n, reason, __FILE__, __LINE__)
 static void ref_by(grpc_fd *fd, int n, const char *reason, const char *file,
                    int line) {
-  gpr_log(GPR_DEBUG, "FD %d %p   ref %d %ld -> %ld [%s; %s:%d]", fd->fd,
-          (void *)fd, n, gpr_atm_no_barrier_load(&fd->refst),
-          gpr_atm_no_barrier_load(&fd->refst) + n, reason, file, line);
+  if (GRPC_TRACER_ON(grpc_trace_fd_refcount)) {
+    gpr_log(GPR_DEBUG,
+            "FD %d %p   ref %d %" PRIdPTR " -> %" PRIdPTR " [%s; %s:%d]",
+            fd->fd, fd, n, gpr_atm_no_barrier_load(&fd->refst),
+            gpr_atm_no_barrier_load(&fd->refst) + n, reason, file, line);
+  }
 #else
 #define REF_BY(fd, n, reason) ref_by(fd, n)
 #define UNREF_BY(ec, fd, n, reason) unref_by(ec, fd, n)
@@ -289,20 +293,21 @@ static void fd_destroy(grpc_exec_ctx *exec_ctx, void *arg, grpc_error *error) {
   gpr_mu_unlock(&fd_freelist_mu);
 }
 
-#ifdef GRPC_FD_REF_COUNT_DEBUG
+#ifndef NDEBUG
 static void unref_by(grpc_exec_ctx *exec_ctx, grpc_fd *fd, int n,
                      const char *reason, const char *file, int line) {
-  gpr_atm old;
-  gpr_log(GPR_DEBUG, "FD %d %p unref %d %ld -> %ld [%s; %s:%d]", fd->fd,
-          (void *)fd, n, gpr_atm_no_barrier_load(&fd->refst),
-          gpr_atm_no_barrier_load(&fd->refst) - n, reason, file, line);
+  if (GRPC_TRACER_ON(grpc_trace_fd_refcount)) {
+    gpr_log(GPR_DEBUG,
+            "FD %d %p unref %d %" PRIdPTR " -> %" PRIdPTR " [%s; %s:%d]",
+            fd->fd, fd, n, gpr_atm_no_barrier_load(&fd->refst),
+            gpr_atm_no_barrier_load(&fd->refst) - n, reason, file, line);
+  }
 #else
 static void unref_by(grpc_exec_ctx *exec_ctx, grpc_fd *fd, int n) {
-  gpr_atm old;
 #endif
-  old = gpr_atm_full_fetch_add(&fd->refst, -n);
+  gpr_atm old = gpr_atm_full_fetch_add(&fd->refst, -n);
   if (old == n) {
-    grpc_closure_sched(exec_ctx, grpc_closure_create(fd_destroy, fd,
+    GRPC_CLOSURE_SCHED(exec_ctx, GRPC_CLOSURE_CREATE(fd_destroy, fd,
                                                      grpc_schedule_on_exec_ctx),
                        GRPC_ERROR_NONE);
   } else {
@@ -347,21 +352,16 @@ static grpc_fd *fd_create(int fd, const char *name) {
   grpc_lfev_init(&new_fd->write_closure);
   gpr_atm_no_barrier_store(&new_fd->read_notifier_pollset, (gpr_atm)NULL);
 
-  GRPC_LOG_IF_ERROR("fd_create",
-                    grpc_wakeup_fd_init(&new_fd->workqueue_wakeup_fd));
-  new_fd->workqueue_scheduler.vtable = &workqueue_scheduler_vtable;
-  new_fd->workqueue_read_mu = GPR_SPINLOCK_INITIALIZER;
-  gpr_mpscq_init(&new_fd->workqueue_items);
-  gpr_atm_no_barrier_store(&new_fd->workqueue_item_count, 0);
-
   new_fd->freelist_next = NULL;
   new_fd->on_done_closure = NULL;
 
   char *fd_name;
   gpr_asprintf(&fd_name, "%s fd=%d", name, fd);
   grpc_iomgr_register_object(&new_fd->iomgr_object, fd_name);
-#ifdef GRPC_FD_REF_COUNT_DEBUG
-  gpr_log(GPR_DEBUG, "FD %d %p create %s", fd, (void *)new_fd, fd_name);
+#ifndef NDEBUG
+  if (GRPC_TRACER_ON(grpc_trace_fd_refcount)) {
+    gpr_log(GPR_DEBUG, "FD %d %p create %s", fd, new_fd, fd_name);
+  }
 #endif
   gpr_free(fd_name);
   return new_fd;
@@ -407,7 +407,7 @@ static void fd_orphan(grpc_exec_ctx *exec_ctx, grpc_fd *fd,
      to be alive (and not added to freelist) until the end of this function */
   REF_BY(fd, 1, reason);
 
-  grpc_closure_sched(exec_ctx, fd->on_done_closure, GRPC_ERROR_REF(error));
+  GRPC_CLOSURE_SCHED(exec_ctx, fd->on_done_closure, GRPC_ERROR_REF(error));
 
   gpr_mu_unlock(&fd->orphaned_mu);
   gpr_mu_unlock(&fd->pollable.po.mu);
@@ -446,91 +446,6 @@ static void fd_notify_on_write(grpc_exec_ctx *exec_ctx, grpc_fd *fd,
   grpc_lfev_notify_on(exec_ctx, &fd->write_closure, closure);
 }
 
-static grpc_workqueue *fd_get_workqueue(grpc_fd *fd) {
-  REF_BY(fd, 2, "return_workqueue");
-  return (grpc_workqueue *)fd;
-}
-
-#ifdef GRPC_WORKQUEUE_REFCOUNT_DEBUG
-static grpc_workqueue *workqueue_ref(grpc_workqueue *workqueue,
-                                     const char *file, int line,
-                                     const char *reason) {
-  if (workqueue != NULL) {
-    ref_by((grpc_fd *)workqueue, 2, file, line, reason);
-  }
-  return workqueue;
-}
-
-static void workqueue_unref(grpc_exec_ctx *exec_ctx, grpc_workqueue *workqueue,
-                            const char *file, int line, const char *reason) {
-  if (workqueue != NULL) {
-    unref_by(exec_ctx, (grpc_fd *)workqueue, 2, file, line, reason);
-  }
-}
-#else
-static grpc_workqueue *workqueue_ref(grpc_workqueue *workqueue) {
-  if (workqueue != NULL) {
-    ref_by((grpc_fd *)workqueue, 2);
-  }
-  return workqueue;
-}
-
-static void workqueue_unref(grpc_exec_ctx *exec_ctx,
-                            grpc_workqueue *workqueue) {
-  if (workqueue != NULL) {
-    unref_by(exec_ctx, (grpc_fd *)workqueue, 2);
-  }
-}
-#endif
-
-static void workqueue_wakeup(grpc_fd *fd) {
-  GRPC_LOG_IF_ERROR("workqueue_enqueue",
-                    grpc_wakeup_fd_wakeup(&fd->workqueue_wakeup_fd));
-}
-
-static void workqueue_enqueue(grpc_exec_ctx *exec_ctx, grpc_closure *closure,
-                              grpc_error *error) {
-  GPR_TIMER_BEGIN("workqueue.enqueue", 0);
-  grpc_fd *fd = (grpc_fd *)(((char *)closure->scheduler) -
-                            offsetof(grpc_fd, workqueue_scheduler));
-  REF_BY(fd, 2, "workqueue_enqueue");
-  gpr_atm last = gpr_atm_no_barrier_fetch_add(&fd->workqueue_item_count, 1);
-  closure->error_data.error = error;
-  gpr_mpscq_push(&fd->workqueue_items, &closure->next_data.atm_next);
-  if (last == 0) {
-    workqueue_wakeup(fd);
-  }
-  UNREF_BY(exec_ctx, fd, 2, "workqueue_enqueue");
-}
-
-static void fd_invoke_workqueue(grpc_exec_ctx *exec_ctx, grpc_fd *fd) {
-  /* handle spurious wakeups */
-  if (!gpr_spinlock_trylock(&fd->workqueue_read_mu)) return;
-  gpr_mpscq_node *n = gpr_mpscq_pop(&fd->workqueue_items);
-  gpr_spinlock_unlock(&fd->workqueue_read_mu);
-  if (n != NULL) {
-    if (gpr_atm_full_fetch_add(&fd->workqueue_item_count, -1) > 1) {
-      workqueue_wakeup(fd);
-    }
-    grpc_closure *c = (grpc_closure *)n;
-    grpc_error *error = c->error_data.error;
-#ifndef NDEBUG
-    c->scheduled = false;
-#endif
-    c->cb(exec_ctx, c->cb_arg, error);
-    GRPC_ERROR_UNREF(error);
-  } else if (gpr_atm_no_barrier_load(&fd->workqueue_item_count) > 0) {
-    /* n == NULL might mean there's work but it's not available to be popped
-     * yet - try to ensure another workqueue wakes up to check shortly if so
-     */
-    workqueue_wakeup(fd);
-  }
-}
-
-static grpc_closure_scheduler *workqueue_scheduler(grpc_workqueue *workqueue) {
-  return &((grpc_fd *)workqueue)->workqueue_scheduler;
-}
-
 /*******************************************************************************
  * Pollable Definitions
  */
@@ -562,7 +477,7 @@ static grpc_error *pollable_materialize(pollable *p) {
       return err;
     }
     struct epoll_event ev = {.events = (uint32_t)(EPOLLIN | EPOLLET),
-                             .data.ptr = &p->wakeup};
+                             .data.ptr = (void *)(1 | (intptr_t)&p->wakeup)};
     if (epoll_ctl(new_epfd, EPOLL_CTL_ADD, p->wakeup.read_fd, &ev) != 0) {
       err = GRPC_OS_ERROR(errno, "epoll_ctl");
       close(new_epfd);
@@ -583,7 +498,7 @@ static grpc_error *pollable_add_fd(pollable *p, grpc_fd *fd) {
   GPR_ASSERT(epfd != -1);
 
   if (GRPC_TRACER_ON(grpc_polling_trace)) {
-    gpr_log(GPR_DEBUG, "add fd %p to pollable %p", fd, p);
+    gpr_log(GPR_DEBUG, "add fd %p (%d) to pollable %p", fd, fd->fd, p);
   }
 
   gpr_mu_lock(&fd->orphaned_mu);
@@ -596,22 +511,7 @@ static grpc_error *pollable_add_fd(pollable *p, grpc_fd *fd) {
       .data.ptr = fd};
   if (epoll_ctl(epfd, EPOLL_CTL_ADD, fd->fd, &ev_fd) != 0) {
     switch (errno) {
-      case EEXIST: /* if this fd is already in the epoll set, the workqueue fd
-                      must also be - just return */
-        gpr_mu_unlock(&fd->orphaned_mu);
-        return GRPC_ERROR_NONE;
-      default:
-        append_error(&error, GRPC_OS_ERROR(errno, "epoll_ctl"), err_desc);
-    }
-  }
-  struct epoll_event ev_wq = {
-      .events = (uint32_t)(EPOLLET | EPOLLIN | EPOLLEXCLUSIVE),
-      .data.ptr = (void *)(1 + (intptr_t)fd)};
-  if (epoll_ctl(epfd, EPOLL_CTL_ADD, fd->workqueue_wakeup_fd.read_fd, &ev_wq) !=
-      0) {
-    switch (errno) {
-      case EEXIST: /* if the workqueue fd is already in the epoll set we're ok
-                      - no need to do anything special */
+      case EEXIST:
         break;
       default:
         append_error(&error, GRPC_OS_ERROR(errno, "epoll_ctl"), err_desc);
@@ -643,18 +543,38 @@ static void pollset_global_shutdown(void) {
   gpr_tls_destroy(&g_current_thread_worker);
 }
 
-static grpc_error *pollset_kick_all(grpc_pollset *pollset) {
+static void pollset_maybe_finish_shutdown(grpc_exec_ctx *exec_ctx,
+                                          grpc_pollset *pollset) {
+  if (pollset->shutdown_closure != NULL && pollset->root_worker == NULL &&
+      pollset->kick_alls_pending == 0) {
+    GRPC_CLOSURE_SCHED(exec_ctx, pollset->shutdown_closure, GRPC_ERROR_NONE);
+    pollset->shutdown_closure = NULL;
+  }
+}
+
+static void do_kick_all(grpc_exec_ctx *exec_ctx, void *arg,
+                        grpc_error *error_unused) {
   grpc_error *error = GRPC_ERROR_NONE;
+  grpc_pollset *pollset = arg;
+  gpr_mu_lock(&pollset->pollable.po.mu);
   if (pollset->root_worker != NULL) {
     grpc_pollset_worker *worker = pollset->root_worker;
     do {
       if (worker->pollable != &pollset->pollable) {
         gpr_mu_lock(&worker->pollable->po.mu);
       }
-      if (worker->initialized_cv) {
+      if (worker->initialized_cv && worker != pollset->root_worker) {
+        if (GRPC_TRACER_ON(grpc_polling_trace)) {
+          gpr_log(GPR_DEBUG, "PS:%p kickall_via_cv %p (pollable %p vs %p)",
+                  pollset, worker, &pollset->pollable, worker->pollable);
+        }
         worker->kicked = true;
         gpr_cv_signal(&worker->cv);
       } else {
+        if (GRPC_TRACER_ON(grpc_polling_trace)) {
+          gpr_log(GPR_DEBUG, "PS:%p kickall_via_wakeup %p (pollable %p vs %p)",
+                  pollset, worker, &pollset->pollable, worker->pollable);
+        }
         append_error(&error, grpc_wakeup_fd_wakeup(&worker->pollable->wakeup),
                      "pollset_shutdown");
       }
@@ -665,7 +585,17 @@ static grpc_error *pollset_kick_all(grpc_pollset *pollset) {
       worker = worker->links[PWL_POLLSET].next;
     } while (worker != pollset->root_worker);
   }
-  return error;
+  pollset->kick_alls_pending--;
+  pollset_maybe_finish_shutdown(exec_ctx, pollset);
+  gpr_mu_unlock(&pollset->pollable.po.mu);
+  GRPC_LOG_IF_ERROR("kick_all", error);
+}
+
+static void pollset_kick_all(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset) {
+  pollset->kick_alls_pending++;
+  GRPC_CLOSURE_SCHED(exec_ctx, GRPC_CLOSURE_CREATE(do_kick_all, pollset,
+                                                   grpc_schedule_on_exec_ctx),
+                     GRPC_ERROR_NONE);
 }
 
 static grpc_error *pollset_kick_inner(grpc_pollset *pollset, pollable *p,
@@ -804,20 +734,12 @@ static grpc_error *fd_become_pollable_locked(grpc_fd *fd) {
   return error;
 }
 
-static void pollset_maybe_finish_shutdown(grpc_exec_ctx *exec_ctx,
-                                          grpc_pollset *pollset) {
-  if (pollset->shutdown_closure != NULL && pollset->root_worker == NULL) {
-    grpc_closure_sched(exec_ctx, pollset->shutdown_closure, GRPC_ERROR_NONE);
-    pollset->shutdown_closure = NULL;
-  }
-}
-
 /* pollset->po.mu lock must be held by the caller before calling this */
 static void pollset_shutdown(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
                              grpc_closure *closure) {
   GPR_ASSERT(pollset->shutdown_closure == NULL);
   pollset->shutdown_closure = closure;
-  GRPC_LOG_IF_ERROR("pollset_shutdown", pollset_kick_all(pollset));
+  pollset_kick_all(exec_ctx, pollset);
   pollset_maybe_finish_shutdown(exec_ctx, pollset);
 }
 
@@ -825,6 +747,46 @@ static bool pollset_is_pollable_fd(grpc_pollset *pollset, pollable *p) {
   return p != &g_empty_pollable && p != &pollset->pollable;
 }
 
+static grpc_error *pollset_process_events(grpc_exec_ctx *exec_ctx,
+                                          grpc_pollset *pollset, bool drain) {
+  static const char *err_desc = "pollset_process_events";
+  grpc_error *error = GRPC_ERROR_NONE;
+  for (int i = 0; (drain || i < MAX_EPOLL_EVENTS_HANDLED_EACH_POLL_CALL) &&
+                  pollset->event_cursor != pollset->event_count;
+       i++) {
+    int n = pollset->event_cursor++;
+    struct epoll_event *ev = &pollset->events[n];
+    void *data_ptr = ev->data.ptr;
+    if (1 & (intptr_t)data_ptr) {
+      if (GRPC_TRACER_ON(grpc_polling_trace)) {
+        gpr_log(GPR_DEBUG, "PS:%p got pollset_wakeup %p", pollset, data_ptr);
+      }
+      append_error(&error, grpc_wakeup_fd_consume_wakeup(
+                               (void *)((~(intptr_t)1) & (intptr_t)data_ptr)),
+                   err_desc);
+    } else {
+      grpc_fd *fd = (grpc_fd *)data_ptr;
+      bool cancel = (ev->events & (EPOLLERR | EPOLLHUP)) != 0;
+      bool read_ev = (ev->events & (EPOLLIN | EPOLLPRI)) != 0;
+      bool write_ev = (ev->events & EPOLLOUT) != 0;
+      if (GRPC_TRACER_ON(grpc_polling_trace)) {
+        gpr_log(GPR_DEBUG,
+                "PS:%p got fd %p: cancel=%d read=%d "
+                "write=%d",
+                pollset, fd, cancel, read_ev, write_ev);
+      }
+      if (read_ev || cancel) {
+        fd_become_readable(exec_ctx, fd, pollset);
+      }
+      if (write_ev || cancel) {
+        fd_become_writable(exec_ctx, fd);
+      }
+    }
+  }
+
+  return error;
+}
+
 /* pollset_shutdown is guaranteed to be called before pollset_destroy. */
 static void pollset_destroy(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset) {
   pollable_destroy(&pollset->pollable);
@@ -832,20 +794,19 @@ static void pollset_destroy(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset) {
     UNREF_BY(exec_ctx, (grpc_fd *)pollset->current_pollable, 2,
              "pollset_pollable");
   }
+  GRPC_LOG_IF_ERROR("pollset_process_events",
+                    pollset_process_events(exec_ctx, pollset, true));
 }
 
-#define MAX_EPOLL_EVENTS 100
-
 static grpc_error *pollset_epoll(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
                                  pollable *p, gpr_timespec now,
                                  gpr_timespec deadline) {
-  struct epoll_event events[MAX_EPOLL_EVENTS];
-  static const char *err_desc = "pollset_poll";
-
   int timeout = poll_deadline_to_millis_timeout(deadline, now);
 
   if (GRPC_TRACER_ON(grpc_polling_trace)) {
-    gpr_log(GPR_DEBUG, "PS:%p poll %p for %dms", pollset, p, timeout);
+    char *desc = pollable_desc(p);
+    gpr_log(GPR_DEBUG, "PS:%p poll %p[%s] for %dms", pollset, p, desc, timeout);
+    gpr_free(desc);
   }
 
   if (timeout != 0) {
@@ -853,7 +814,7 @@ static grpc_error *pollset_epoll(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
   }
   int r;
   do {
-    r = epoll_wait(p->epfd, events, MAX_EPOLL_EVENTS, timeout);
+    r = epoll_wait(p->epfd, pollset->events, MAX_EPOLL_EVENTS, timeout);
   } while (r < 0 && errno == EINTR);
   if (timeout != 0) {
     GRPC_SCHEDULING_END_BLOCKING_REGION;
@@ -865,43 +826,10 @@ static grpc_error *pollset_epoll(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
     gpr_log(GPR_DEBUG, "PS:%p poll %p got %d events", pollset, p, r);
   }
 
-  grpc_error *error = GRPC_ERROR_NONE;
-  for (int i = 0; i < r; i++) {
-    void *data_ptr = events[i].data.ptr;
-    if (data_ptr == &p->wakeup) {
-      if (GRPC_TRACER_ON(grpc_polling_trace)) {
-        gpr_log(GPR_DEBUG, "PS:%p poll %p got pollset_wakeup", pollset, p);
-      }
-      append_error(&error, grpc_wakeup_fd_consume_wakeup(&p->wakeup), err_desc);
-    } else {
-      grpc_fd *fd = (grpc_fd *)(((intptr_t)data_ptr) & ~(intptr_t)1);
-      bool is_workqueue = (((intptr_t)data_ptr) & 1) != 0;
-      bool cancel = (events[i].events & (EPOLLERR | EPOLLHUP)) != 0;
-      bool read_ev = (events[i].events & (EPOLLIN | EPOLLPRI)) != 0;
-      bool write_ev = (events[i].events & EPOLLOUT) != 0;
-      if (GRPC_TRACER_ON(grpc_polling_trace)) {
-        gpr_log(GPR_DEBUG,
-                "PS:%p poll %p got fd %p: is_wq=%d cancel=%d read=%d "
-                "write=%d",
-                pollset, p, fd, is_workqueue, cancel, read_ev, write_ev);
-      }
-      if (is_workqueue) {
-        append_error(&error,
-                     grpc_wakeup_fd_consume_wakeup(&fd->workqueue_wakeup_fd),
-                     err_desc);
-        fd_invoke_workqueue(exec_ctx, fd);
-      } else {
-        if (read_ev || cancel) {
-          fd_become_readable(exec_ctx, fd, pollset);
-        }
-        if (write_ev || cancel) {
-          fd_become_writable(exec_ctx, fd);
-        }
-      }
-    }
-  }
+  pollset->event_cursor = 0;
+  pollset->event_count = r;
 
-  return error;
+  return GRPC_ERROR_NONE;
 }
 
 /* Return true if first in list */
@@ -1053,10 +981,13 @@ static grpc_error *pollset_work(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
       gpr_mu_unlock(&worker.pollable->po.mu);
     }
     gpr_mu_unlock(&pollset->pollable.po.mu);
-    append_error(&error, pollset_epoll(exec_ctx, pollset, worker.pollable, now,
-                                       deadline),
+    if (pollset->event_cursor == pollset->event_count) {
+      append_error(&error, pollset_epoll(exec_ctx, pollset, worker.pollable,
+                                         now, deadline),
+                   err_desc);
+    }
+    append_error(&error, pollset_process_events(exec_ctx, pollset, false),
                  err_desc);
-    grpc_exec_ctx_flush(exec_ctx);
     gpr_mu_lock(&pollset->pollable.po.mu);
     if (worker.pollable != &pollset->pollable) {
       gpr_mu_lock(&worker.pollable->po.mu);
@@ -1069,6 +1000,11 @@ static grpc_error *pollset_work(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
   if (worker.pollable != &pollset->pollable) {
     gpr_mu_unlock(&worker.pollable->po.mu);
   }
+  if (grpc_exec_ctx_has_work(exec_ctx)) {
+    gpr_mu_unlock(&pollset->pollable.po.mu);
+    grpc_exec_ctx_flush(exec_ctx);
+    gpr_mu_lock(&pollset->pollable.po.mu);
+  }
   return error;
 }
 
@@ -1085,37 +1021,45 @@ static grpc_error *pollset_add_fd_locked(grpc_exec_ctx *exec_ctx,
   static const char *err_desc = "pollset_add_fd";
   grpc_error *error = GRPC_ERROR_NONE;
   if (pollset->current_pollable == &g_empty_pollable) {
-    if (GRPC_TRACER_ON(grpc_polling_trace))
+    if (GRPC_TRACER_ON(grpc_polling_trace)) {
       gpr_log(GPR_DEBUG,
               "PS:%p add fd %p; transition pollable from empty to fd", pollset,
               fd);
+    }
     /* empty pollable --> single fd pollable */
-    append_error(&error, pollset_kick_all(pollset), err_desc);
+    pollset_kick_all(exec_ctx, pollset);
     pollset->current_pollable = &fd->pollable;
     if (!fd_locked) gpr_mu_lock(&fd->pollable.po.mu);
     append_error(&error, fd_become_pollable_locked(fd), err_desc);
     if (!fd_locked) gpr_mu_unlock(&fd->pollable.po.mu);
     REF_BY(fd, 2, "pollset_pollable");
   } else if (pollset->current_pollable == &pollset->pollable) {
-    if (GRPC_TRACER_ON(grpc_polling_trace))
+    if (GRPC_TRACER_ON(grpc_polling_trace)) {
       gpr_log(GPR_DEBUG, "PS:%p add fd %p; already multipolling", pollset, fd);
+    }
     append_error(&error, pollable_add_fd(pollset->current_pollable, fd),
                  err_desc);
   } else if (pollset->current_pollable != &fd->pollable) {
     grpc_fd *had_fd = (grpc_fd *)pollset->current_pollable;
-    if (GRPC_TRACER_ON(grpc_polling_trace))
+    if (GRPC_TRACER_ON(grpc_polling_trace)) {
       gpr_log(GPR_DEBUG,
               "PS:%p add fd %p; transition pollable from fd %p to multipoller",
               pollset, fd, had_fd);
-    append_error(&error, pollset_kick_all(pollset), err_desc);
+    }
+    /* Introduce a spurious completion.
+       If we do not, then it may be that the fd-specific epoll set consumed
+       a completion without being polled, leading to a missed edge going up. */
+    grpc_lfev_set_ready(exec_ctx, &had_fd->read_closure);
+    grpc_lfev_set_ready(exec_ctx, &had_fd->write_closure);
+    pollset_kick_all(exec_ctx, pollset);
     pollset->current_pollable = &pollset->pollable;
     if (append_error(&error, pollable_materialize(&pollset->pollable),
                      err_desc)) {
       pollable_add_fd(&pollset->pollable, had_fd);
       pollable_add_fd(&pollset->pollable, fd);
     }
-    grpc_closure_sched(exec_ctx,
-                       grpc_closure_create(unref_fd_no_longer_poller, had_fd,
+    GRPC_CLOSURE_SCHED(exec_ctx,
+                       GRPC_CLOSURE_CREATE(unref_fd_no_longer_poller, had_fd,
                                            grpc_schedule_on_exec_ctx),
                        GRPC_ERROR_NONE);
   }
@@ -1449,7 +1393,6 @@ static const grpc_event_engine_vtable vtable = {
     .fd_notify_on_read = fd_notify_on_read,
     .fd_notify_on_write = fd_notify_on_write,
     .fd_get_read_notifier_pollset = fd_get_read_notifier_pollset,
-    .fd_get_workqueue = fd_get_workqueue,
 
     .pollset_init = pollset_init,
     .pollset_shutdown = pollset_shutdown,
@@ -1467,17 +1410,11 @@ static const grpc_event_engine_vtable vtable = {
     .pollset_set_add_fd = pollset_set_add_fd,
     .pollset_set_del_fd = pollset_set_del_fd,
 
-    .workqueue_ref = workqueue_ref,
-    .workqueue_unref = workqueue_unref,
-    .workqueue_scheduler = workqueue_scheduler,
-
     .shutdown_engine = shutdown_engine,
 };
 
 const grpc_event_engine_vtable *grpc_init_epollex_linux(
     bool explicitly_requested) {
-  if (!explicitly_requested) return NULL;
-
   if (!grpc_has_wakeup_fd()) {
     return NULL;
   }
diff --git a/src/core/lib/iomgr/ev_epollex_linux.h b/src/core/lib/iomgr/ev_epollex_linux.h
index a078a7f19a..cff9b43c02 100644
--- a/src/core/lib/iomgr/ev_epollex_linux.h
+++ b/src/core/lib/iomgr/ev_epollex_linux.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/ev_epollsig_linux.c b/src/core/lib/iomgr/ev_epollsig_linux.c
index 52362a62f4..3c4ca9c7c5 100644
--- a/src/core/lib/iomgr/ev_epollsig_linux.c
+++ b/src/core/lib/iomgr/ev_epollsig_linux.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -59,20 +44,16 @@
 #include "src/core/lib/iomgr/lockfree_event.h"
 #include "src/core/lib/iomgr/timer.h"
 #include "src/core/lib/iomgr/wakeup_fd_posix.h"
-#include "src/core/lib/iomgr/workqueue.h"
 #include "src/core/lib/profiling/timers.h"
 #include "src/core/lib/support/block_annotate.h"
 
 #define GRPC_POLLSET_KICK_BROADCAST ((grpc_pollset_worker *)1)
 
-#define GRPC_POLLING_TRACE(fmt, ...)        \
+#define GRPC_POLLING_TRACE(...)             \
   if (GRPC_TRACER_ON(grpc_polling_trace)) { \
-    gpr_log(GPR_INFO, (fmt), __VA_ARGS__);  \
+    gpr_log(GPR_INFO, __VA_ARGS__);         \
   }
 
-/* Uncomment the following to enable extra checks on poll_object operations */
-/* #define PO_DEBUG */
-
 static int grpc_wakeup_signal = -1;
 static bool is_grpc_wakeup_signal_initialized = false;
 
@@ -101,7 +82,7 @@ typedef enum {
 } poll_obj_type;
 
 typedef struct poll_obj {
-#ifdef PO_DEBUG
+#ifndef NDEBUG
   poll_obj_type obj_type;
 #endif
   gpr_mu mu;
@@ -156,8 +137,7 @@ struct grpc_fd {
 };
 
 /* Reference counting for fds */
-// #define GRPC_FD_REF_COUNT_DEBUG
-#ifdef GRPC_FD_REF_COUNT_DEBUG
+#ifndef NDEBUG
 static void fd_ref(grpc_fd *fd, const char *reason, const char *file, int line);
 static void fd_unref(grpc_fd *fd, const char *reason, const char *file,
                      int line);
@@ -177,23 +157,21 @@ static void fd_global_shutdown(void);
  * Polling island Declarations
  */
 
-#ifdef GRPC_WORKQUEUE_REFCOUNT_DEBUG
+#ifndef NDEBUG
 
 #define PI_ADD_REF(p, r) pi_add_ref_dbg((p), (r), __FILE__, __LINE__)
 #define PI_UNREF(exec_ctx, p, r) \
   pi_unref_dbg((exec_ctx), (p), (r), __FILE__, __LINE__)
 
-#else /* defined(GRPC_WORKQUEUE_REFCOUNT_DEBUG) */
+#else
 
 #define PI_ADD_REF(p, r) pi_add_ref((p))
 #define PI_UNREF(exec_ctx, p, r) pi_unref((exec_ctx), (p))
 
-#endif /* !defined(GRPC_PI_REF_COUNT_DEBUG) */
+#endif
 
 /* This is also used as grpc_workqueue (by directly casing it) */
 typedef struct polling_island {
-  grpc_closure_scheduler workqueue_scheduler;
-
   gpr_mu mu;
   /* Ref count. Use PI_ADD_REF() and PI_UNREF() macros to increment/decrement
      the refcount.
@@ -214,15 +192,6 @@ typedef struct polling_island {
 
   /* Number of threads currently polling on this island */
   gpr_atm poller_count;
-  /* Mutex guarding the read end of the workqueue (must be held to pop from
-   * workqueue_items) */
-  gpr_mu workqueue_read_mu;
-  /* Queue of closures to be executed */
-  gpr_mpscq workqueue_items;
-  /* Count of items in workqueue_items */
-  gpr_atm workqueue_item_count;
-  /* Wakeup fd used to wake pollers to check the contents of workqueue_items */
-  grpc_wakeup_fd workqueue_wakeup_fd;
 
   /* The fd of the underlying epoll set */
   int epoll_fd;
@@ -297,8 +266,6 @@ static __thread polling_island *g_current_thread_polling_island;
 
 /* Forward declaration */
 static void polling_island_delete(grpc_exec_ctx *exec_ctx, polling_island *pi);
-static void workqueue_enqueue(grpc_exec_ctx *exec_ctx, grpc_closure *closure,
-                              grpc_error *error);
 
 #ifdef GRPC_TSAN
 /* Currently TSAN may incorrectly flag data races between epoll_ctl and
@@ -311,57 +278,30 @@ static void workqueue_enqueue(grpc_exec_ctx *exec_ctx, grpc_closure *closure,
 gpr_atm g_epoll_sync;
 #endif /* defined(GRPC_TSAN) */
 
-static const grpc_closure_scheduler_vtable workqueue_scheduler_vtable = {
-    workqueue_enqueue, workqueue_enqueue, "workqueue"};
-
 static void pi_add_ref(polling_island *pi);
 static void pi_unref(grpc_exec_ctx *exec_ctx, polling_island *pi);
 
-#ifdef GRPC_WORKQUEUE_REFCOUNT_DEBUG
+#ifndef NDEBUG
 static void pi_add_ref_dbg(polling_island *pi, const char *reason,
                            const char *file, int line) {
-  long old_cnt = gpr_atm_acq_load(&pi->ref_count);
+  if (GRPC_TRACER_ON(grpc_polling_trace)) {
+    gpr_atm old_cnt = gpr_atm_acq_load(&pi->ref_count);
+    gpr_log(GPR_DEBUG, "Add ref pi: %p, old:%" PRIdPTR " -> new:%" PRIdPTR
+                       " (%s) - (%s, %d)",
+            pi, old_cnt, old_cnt + 1, reason, file, line);
+  }
   pi_add_ref(pi);
-  gpr_log(GPR_DEBUG, "Add ref pi: %p, old: %ld -> new:%ld (%s) - (%s, %d)",
-          (void *)pi, old_cnt, old_cnt + 1, reason, file, line);
 }
 
 static void pi_unref_dbg(grpc_exec_ctx *exec_ctx, polling_island *pi,
                          const char *reason, const char *file, int line) {
-  long old_cnt = gpr_atm_acq_load(&pi->ref_count);
-  pi_unref(exec_ctx, pi);
-  gpr_log(GPR_DEBUG, "Unref pi: %p, old:%ld -> new:%ld (%s) - (%s, %d)",
-          (void *)pi, old_cnt, (old_cnt - 1), reason, file, line);
-}
-
-static grpc_workqueue *workqueue_ref(grpc_workqueue *workqueue,
-                                     const char *file, int line,
-                                     const char *reason) {
-  if (workqueue != NULL) {
-    pi_add_ref_dbg((polling_island *)workqueue, reason, file, line);
-  }
-  return workqueue;
-}
-
-static void workqueue_unref(grpc_exec_ctx *exec_ctx, grpc_workqueue *workqueue,
-                            const char *file, int line, const char *reason) {
-  if (workqueue != NULL) {
-    pi_unref_dbg(exec_ctx, (polling_island *)workqueue, reason, file, line);
-  }
-}
-#else
-static grpc_workqueue *workqueue_ref(grpc_workqueue *workqueue) {
-  if (workqueue != NULL) {
-    pi_add_ref((polling_island *)workqueue);
-  }
-  return workqueue;
-}
-
-static void workqueue_unref(grpc_exec_ctx *exec_ctx,
-                            grpc_workqueue *workqueue) {
-  if (workqueue != NULL) {
-    pi_unref(exec_ctx, (polling_island *)workqueue);
+  if (GRPC_TRACER_ON(grpc_polling_trace)) {
+    gpr_atm old_cnt = gpr_atm_acq_load(&pi->ref_count);
+    gpr_log(GPR_DEBUG, "Unref pi: %p, old:%" PRIdPTR " -> new:%" PRIdPTR
+                       " (%s) - (%s, %d)",
+            pi, old_cnt, (old_cnt - 1), reason, file, line);
   }
+  pi_unref(exec_ctx, pi);
 }
 #endif
 
@@ -526,26 +466,16 @@ static polling_island *polling_island_create(grpc_exec_ctx *exec_ctx,
   *error = GRPC_ERROR_NONE;
 
   pi = gpr_malloc(sizeof(*pi));
-  pi->workqueue_scheduler.vtable = &workqueue_scheduler_vtable;
   gpr_mu_init(&pi->mu);
   pi->fd_cnt = 0;
   pi->fd_capacity = 0;
   pi->fds = NULL;
   pi->epoll_fd = -1;
 
-  gpr_mu_init(&pi->workqueue_read_mu);
-  gpr_mpscq_init(&pi->workqueue_items);
-  gpr_atm_rel_store(&pi->workqueue_item_count, 0);
-
   gpr_atm_rel_store(&pi->ref_count, 0);
   gpr_atm_rel_store(&pi->poller_count, 0);
   gpr_atm_rel_store(&pi->merged_to, (gpr_atm)NULL);
 
-  if (!append_error(error, grpc_wakeup_fd_init(&pi->workqueue_wakeup_fd),
-                    err_desc)) {
-    goto done;
-  }
-
   pi->epoll_fd = epoll_create1(EPOLL_CLOEXEC);
 
   if (pi->epoll_fd < 0) {
@@ -553,8 +483,6 @@ static polling_island *polling_island_create(grpc_exec_ctx *exec_ctx,
     goto done;
   }
 
-  polling_island_add_wakeup_fd_locked(pi, &pi->workqueue_wakeup_fd, error);
-
   if (initial_fd != NULL) {
     polling_island_add_fds_locked(pi, &initial_fd, 1, true, error);
   }
@@ -573,11 +501,7 @@ static void polling_island_delete(grpc_exec_ctx *exec_ctx, polling_island *pi) {
   if (pi->epoll_fd >= 0) {
     close(pi->epoll_fd);
   }
-  GPR_ASSERT(gpr_atm_no_barrier_load(&pi->workqueue_item_count) == 0);
-  gpr_mu_destroy(&pi->workqueue_read_mu);
-  gpr_mpscq_destroy(&pi->workqueue_items);
   gpr_mu_destroy(&pi->mu);
-  grpc_wakeup_fd_destroy(&pi->workqueue_wakeup_fd);
   gpr_free(pi->fds);
   gpr_free(pi);
 }
@@ -722,45 +646,6 @@ static void polling_island_unlock_pair(polling_island *p, polling_island *q) {
   }
 }
 
-static void workqueue_maybe_wakeup(polling_island *pi) {
-  /* If this thread is the current poller, then it may be that it's about to
-     decrement the current poller count, so we need to look past this thread */
-  bool is_current_poller = (g_current_thread_polling_island == pi);
-  gpr_atm min_current_pollers_for_wakeup = is_current_poller ? 1 : 0;
-  gpr_atm current_pollers = gpr_atm_no_barrier_load(&pi->poller_count);
-  /* Only issue a wakeup if it's likely that some poller could come in and take
-     it right now. Note that since we do an anticipatory mpscq_pop every poll
-     loop, it's ok if we miss the wakeup here, as we'll get the work item when
-     the next poller enters anyway. */
-  if (current_pollers > min_current_pollers_for_wakeup) {
-    GRPC_LOG_IF_ERROR("workqueue_wakeup_fd",
-                      grpc_wakeup_fd_wakeup(&pi->workqueue_wakeup_fd));
-  }
-}
-
-static void workqueue_move_items_to_parent(polling_island *q) {
-  polling_island *p = (polling_island *)gpr_atm_no_barrier_load(&q->merged_to);
-  if (p == NULL) {
-    return;
-  }
-  gpr_mu_lock(&q->workqueue_read_mu);
-  int num_added = 0;
-  while (gpr_atm_no_barrier_load(&q->workqueue_item_count) > 0) {
-    gpr_mpscq_node *n = gpr_mpscq_pop(&q->workqueue_items);
-    if (n != NULL) {
-      gpr_atm_no_barrier_fetch_add(&q->workqueue_item_count, -1);
-      gpr_atm_no_barrier_fetch_add(&p->workqueue_item_count, 1);
-      gpr_mpscq_push(&p->workqueue_items, n);
-      num_added++;
-    }
-  }
-  gpr_mu_unlock(&q->workqueue_read_mu);
-  if (num_added > 0) {
-    workqueue_maybe_wakeup(p);
-  }
-  workqueue_move_items_to_parent(p);
-}
-
 static polling_island *polling_island_merge(polling_island *p,
                                             polling_island *q,
                                             grpc_error **error) {
@@ -785,8 +670,6 @@ static polling_island *polling_island_merge(polling_island *p,
     /* Add the 'merged_to' link from p --> q */
     gpr_atm_rel_store(&p->merged_to, (gpr_atm)q);
     PI_ADD_REF(q, "pi_merge"); /* To account for the new incoming ref from p */
-
-    workqueue_move_items_to_parent(p);
   }
   /* else if p == q, nothing needs to be done */
 
@@ -797,32 +680,6 @@ static polling_island *polling_island_merge(polling_island *p,
   return q;
 }
 
-static void workqueue_enqueue(grpc_exec_ctx *exec_ctx, grpc_closure *closure,
-                              grpc_error *error) {
-  GPR_TIMER_BEGIN("workqueue.enqueue", 0);
-  grpc_workqueue *workqueue = (grpc_workqueue *)closure->scheduler;
-  /* take a ref to the workqueue: otherwise it can happen that whatever events
-   * this kicks off ends up destroying the workqueue before this function
-   * completes */
-  GRPC_WORKQUEUE_REF(workqueue, "enqueue");
-  polling_island *pi = (polling_island *)workqueue;
-  gpr_atm last = gpr_atm_no_barrier_fetch_add(&pi->workqueue_item_count, 1);
-  closure->error_data.error = error;
-  gpr_mpscq_push(&pi->workqueue_items, &closure->next_data.atm_next);
-  if (last == 0) {
-    workqueue_maybe_wakeup(pi);
-  }
-  workqueue_move_items_to_parent(pi);
-  GRPC_WORKQUEUE_UNREF(exec_ctx, workqueue, "enqueue");
-  GPR_TIMER_END("workqueue.enqueue", 0);
-}
-
-static grpc_closure_scheduler *workqueue_scheduler(grpc_workqueue *workqueue) {
-  polling_island *pi = (polling_island *)workqueue;
-  return workqueue == NULL ? grpc_schedule_on_exec_ctx
-                           : &pi->workqueue_scheduler;
-}
-
 static grpc_error *polling_island_global_init() {
   grpc_error *error = GRPC_ERROR_NONE;
 
@@ -863,14 +720,17 @@ static void polling_island_global_shutdown() {
 static grpc_fd *fd_freelist = NULL;
 static gpr_mu fd_freelist_mu;
 
-#ifdef GRPC_FD_REF_COUNT_DEBUG
+#ifndef NDEBUG
 #define REF_BY(fd, n, reason) ref_by(fd, n, reason, __FILE__, __LINE__)
 #define UNREF_BY(fd, n, reason) unref_by(fd, n, reason, __FILE__, __LINE__)
 static void ref_by(grpc_fd *fd, int n, const char *reason, const char *file,
                    int line) {
-  gpr_log(GPR_DEBUG, "FD %d %p   ref %d %ld -> %ld [%s; %s:%d]", fd->fd,
-          (void *)fd, n, gpr_atm_no_barrier_load(&fd->refst),
-          gpr_atm_no_barrier_load(&fd->refst) + n, reason, file, line);
+  if (GRPC_TRACER_ON(grpc_trace_fd_refcount)) {
+    gpr_log(GPR_DEBUG,
+            "FD %d %p   ref %d %" PRIdPTR " -> %" PRIdPTR " [%s; %s:%d]",
+            fd->fd, fd, n, gpr_atm_no_barrier_load(&fd->refst),
+            gpr_atm_no_barrier_load(&fd->refst) + n, reason, file, line);
+  }
 #else
 #define REF_BY(fd, n, reason) ref_by(fd, n)
 #define UNREF_BY(fd, n, reason) unref_by(fd, n)
@@ -879,18 +739,19 @@ static void ref_by(grpc_fd *fd, int n) {
   GPR_ASSERT(gpr_atm_no_barrier_fetch_add(&fd->refst, n) > 0);
 }
 
-#ifdef GRPC_FD_REF_COUNT_DEBUG
+#ifndef NDEBUG
 static void unref_by(grpc_fd *fd, int n, const char *reason, const char *file,
                      int line) {
-  gpr_atm old;
-  gpr_log(GPR_DEBUG, "FD %d %p unref %d %ld -> %ld [%s; %s:%d]", fd->fd,
-          (void *)fd, n, gpr_atm_no_barrier_load(&fd->refst),
-          gpr_atm_no_barrier_load(&fd->refst) - n, reason, file, line);
+  if (GRPC_TRACER_ON(grpc_trace_fd_refcount)) {
+    gpr_log(GPR_DEBUG,
+            "FD %d %p unref %d %" PRIdPTR " -> %" PRIdPTR " [%s; %s:%d]",
+            fd->fd, fd, n, gpr_atm_no_barrier_load(&fd->refst),
+            gpr_atm_no_barrier_load(&fd->refst) - n, reason, file, line);
+  }
 #else
 static void unref_by(grpc_fd *fd, int n) {
-  gpr_atm old;
 #endif
-  old = gpr_atm_full_fetch_add(&fd->refst, -n);
+  gpr_atm old = gpr_atm_full_fetch_add(&fd->refst, -n);
   if (old == n) {
     /* Add the fd to the freelist */
     gpr_mu_lock(&fd_freelist_mu);
@@ -908,7 +769,7 @@ static void unref_by(grpc_fd *fd, int n) {
 }
 
 /* Increment refcount by two to avoid changing the orphan bit */
-#ifdef GRPC_FD_REF_COUNT_DEBUG
+#ifndef NDEBUG
 static void fd_ref(grpc_fd *fd, const char *reason, const char *file,
                    int line) {
   ref_by(fd, 2, reason, file, line);
@@ -957,7 +818,7 @@ static grpc_fd *fd_create(int fd, const char *name) {
    * would be holding a lock to it anyway. */
   gpr_mu_lock(&new_fd->po.mu);
   new_fd->po.pi = NULL;
-#ifdef PO_DEBUG
+#ifndef NDEBUG
   new_fd->po.obj_type = POLL_OBJ_FD;
 #endif
 
@@ -976,9 +837,6 @@ static grpc_fd *fd_create(int fd, const char *name) {
   char *fd_name;
   gpr_asprintf(&fd_name, "%s fd=%d", name, fd);
   grpc_iomgr_register_object(&new_fd->iomgr_object, fd_name);
-#ifdef GRPC_FD_REF_COUNT_DEBUG
-  gpr_log(GPR_DEBUG, "FD %d %p create %s", fd, (void *)new_fd, fd_name);
-#endif
   gpr_free(fd_name);
   return new_fd;
 }
@@ -1036,7 +894,7 @@ static void fd_orphan(grpc_exec_ctx *exec_ctx, grpc_fd *fd,
     fd->po.pi = NULL;
   }
 
-  grpc_closure_sched(exec_ctx, fd->on_done_closure, GRPC_ERROR_REF(error));
+  GRPC_CLOSURE_SCHED(exec_ctx, fd->on_done_closure, GRPC_ERROR_REF(error));
 
   gpr_mu_unlock(&fd->po.mu);
   UNREF_BY(fd, 2, reason); /* Drop the reference */
@@ -1047,7 +905,10 @@ static void fd_orphan(grpc_exec_ctx *exec_ctx, grpc_fd *fd,
        unhappy. */
     PI_UNREF(exec_ctx, unref_pi, "fd_orphan");
   }
-  GRPC_LOG_IF_ERROR("fd_orphan", GRPC_ERROR_REF(error));
+  if (error != GRPC_ERROR_NONE) {
+    const char *msg = grpc_error_string(error);
+    gpr_log(GPR_DEBUG, "fd_orphan: %s", msg);
+  }
   GRPC_ERROR_UNREF(error);
 }
 
@@ -1081,14 +942,6 @@ static void fd_notify_on_write(grpc_exec_ctx *exec_ctx, grpc_fd *fd,
   grpc_lfev_notify_on(exec_ctx, &fd->write_closure, closure);
 }
 
-static grpc_workqueue *fd_get_workqueue(grpc_fd *fd) {
-  gpr_mu_lock(&fd->po.mu);
-  grpc_workqueue *workqueue =
-      GRPC_WORKQUEUE_REF((grpc_workqueue *)fd->po.pi, "fd_get_workqueue");
-  gpr_mu_unlock(&fd->po.mu);
-  return workqueue;
-}
-
 /*******************************************************************************
  * Pollset Definitions
  */
@@ -1223,7 +1076,7 @@ static void pollset_init(grpc_pollset *pollset, gpr_mu **mu) {
   gpr_mu_init(&pollset->po.mu);
   *mu = &pollset->po.mu;
   pollset->po.pi = NULL;
-#ifdef PO_DEBUG
+#ifndef NDEBUG
   pollset->po.obj_type = POLL_OBJ_POLLSET;
 #endif
 
@@ -1295,7 +1148,7 @@ static void finish_shutdown_locked(grpc_exec_ctx *exec_ctx,
 
   /* Release the ref and set pollset->po.pi to NULL */
   pollset_release_polling_island(exec_ctx, pollset, "ps_shutdown");
-  grpc_closure_sched(exec_ctx, pollset->shutdown_done, GRPC_ERROR_NONE);
+  GRPC_CLOSURE_SCHED(exec_ctx, pollset->shutdown_done, GRPC_ERROR_NONE);
 }
 
 /* pollset->po.mu lock must be held by the caller before calling this */
@@ -1326,33 +1179,6 @@ static void pollset_destroy(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset) {
   gpr_mu_destroy(&pollset->po.mu);
 }
 
-static bool maybe_do_workqueue_work(grpc_exec_ctx *exec_ctx,
-                                    polling_island *pi) {
-  if (gpr_mu_trylock(&pi->workqueue_read_mu)) {
-    gpr_mpscq_node *n = gpr_mpscq_pop(&pi->workqueue_items);
-    gpr_mu_unlock(&pi->workqueue_read_mu);
-    if (n != NULL) {
-      if (gpr_atm_full_fetch_add(&pi->workqueue_item_count, -1) > 1) {
-        workqueue_maybe_wakeup(pi);
-      }
-      grpc_closure *c = (grpc_closure *)n;
-      grpc_error *error = c->error_data.error;
-#ifndef NDEBUG
-      c->scheduled = false;
-#endif
-      c->cb(exec_ctx, c->cb_arg, error);
-      GRPC_ERROR_UNREF(error);
-      return true;
-    } else if (gpr_atm_no_barrier_load(&pi->workqueue_item_count) > 0) {
-      /* n == NULL might mean there's work but it's not available to be popped
-       * yet - try to ensure another workqueue wakes up to check shortly if so
-       */
-      workqueue_maybe_wakeup(pi);
-    }
-  }
-  return false;
-}
-
 #define GRPC_EPOLL_MAX_EVENTS 100
 /* Note: sig_mask contains the signal mask to use *during* epoll_wait() */
 static void pollset_work_and_unlock(grpc_exec_ctx *exec_ctx,
@@ -1408,72 +1234,61 @@ static void pollset_work_and_unlock(grpc_exec_ctx *exec_ctx,
   PI_ADD_REF(pi, "ps_work");
   gpr_mu_unlock(&pollset->po.mu);
 
-  /* If we get some workqueue work to do, it might end up completing an item on
-     the completion queue, so there's no need to poll... so we skip that and
-     redo the complete loop to verify */
-  if (!maybe_do_workqueue_work(exec_ctx, pi)) {
-    gpr_atm_no_barrier_fetch_add(&pi->poller_count, 1);
-    g_current_thread_polling_island = pi;
-
-    GRPC_SCHEDULING_START_BLOCKING_REGION;
-    ep_rv = epoll_pwait(epoll_fd, ep_ev, GRPC_EPOLL_MAX_EVENTS, timeout_ms,
-                        sig_mask);
-    GRPC_SCHEDULING_END_BLOCKING_REGION;
-    if (ep_rv < 0) {
-      if (errno != EINTR) {
-        gpr_asprintf(&err_msg,
-                     "epoll_wait() epoll fd: %d failed with error: %d (%s)",
-                     epoll_fd, errno, strerror(errno));
-        append_error(error, GRPC_OS_ERROR(errno, err_msg), err_desc);
-      } else {
-        /* We were interrupted. Save an interation by doing a zero timeout
-           epoll_wait to see if there are any other events of interest */
-        GRPC_POLLING_TRACE(
-            "pollset_work: pollset: %p, worker: %p received kick",
-            (void *)pollset, (void *)worker);
-        ep_rv = epoll_wait(epoll_fd, ep_ev, GRPC_EPOLL_MAX_EVENTS, 0);
-      }
+  gpr_atm_no_barrier_fetch_add(&pi->poller_count, 1);
+  g_current_thread_polling_island = pi;
+
+  GRPC_SCHEDULING_START_BLOCKING_REGION;
+  ep_rv =
+      epoll_pwait(epoll_fd, ep_ev, GRPC_EPOLL_MAX_EVENTS, timeout_ms, sig_mask);
+  GRPC_SCHEDULING_END_BLOCKING_REGION;
+  if (ep_rv < 0) {
+    if (errno != EINTR) {
+      gpr_asprintf(&err_msg,
+                   "epoll_wait() epoll fd: %d failed with error: %d (%s)",
+                   epoll_fd, errno, strerror(errno));
+      append_error(error, GRPC_OS_ERROR(errno, err_msg), err_desc);
+    } else {
+      /* We were interrupted. Save an interation by doing a zero timeout
+         epoll_wait to see if there are any other events of interest */
+      GRPC_POLLING_TRACE("pollset_work: pollset: %p, worker: %p received kick",
+                         (void *)pollset, (void *)worker);
+      ep_rv = epoll_wait(epoll_fd, ep_ev, GRPC_EPOLL_MAX_EVENTS, 0);
     }
+  }
 
 #ifdef GRPC_TSAN
-    /* See the definition of g_poll_sync for more details */
-    gpr_atm_acq_load(&g_epoll_sync);
+  /* See the definition of g_poll_sync for more details */
+  gpr_atm_acq_load(&g_epoll_sync);
 #endif /* defined(GRPC_TSAN) */
 
-    for (int i = 0; i < ep_rv; ++i) {
-      void *data_ptr = ep_ev[i].data.ptr;
-      if (data_ptr == &pi->workqueue_wakeup_fd) {
-        append_error(error,
-                     grpc_wakeup_fd_consume_wakeup(&pi->workqueue_wakeup_fd),
-                     err_desc);
-        maybe_do_workqueue_work(exec_ctx, pi);
-      } else if (data_ptr == &polling_island_wakeup_fd) {
-        GRPC_POLLING_TRACE(
-            "pollset_work: pollset: %p, worker: %p polling island (epoll_fd: "
-            "%d) got merged",
-            (void *)pollset, (void *)worker, epoll_fd);
-        /* This means that our polling island is merged with a different
-           island. We do not have to do anything here since the subsequent call
-           to the function pollset_work_and_unlock() will pick up the correct
-           epoll_fd */
-      } else {
-        grpc_fd *fd = data_ptr;
-        int cancel = ep_ev[i].events & (EPOLLERR | EPOLLHUP);
-        int read_ev = ep_ev[i].events & (EPOLLIN | EPOLLPRI);
-        int write_ev = ep_ev[i].events & EPOLLOUT;
-        if (read_ev || cancel) {
-          fd_become_readable(exec_ctx, fd, pollset);
-        }
-        if (write_ev || cancel) {
-          fd_become_writable(exec_ctx, fd);
-        }
+  for (int i = 0; i < ep_rv; ++i) {
+    void *data_ptr = ep_ev[i].data.ptr;
+    if (data_ptr == &polling_island_wakeup_fd) {
+      GRPC_POLLING_TRACE(
+          "pollset_work: pollset: %p, worker: %p polling island (epoll_fd: "
+          "%d) got merged",
+          (void *)pollset, (void *)worker, epoll_fd);
+      /* This means that our polling island is merged with a different
+         island. We do not have to do anything here since the subsequent call
+         to the function pollset_work_and_unlock() will pick up the correct
+         epoll_fd */
+    } else {
+      grpc_fd *fd = data_ptr;
+      int cancel = ep_ev[i].events & (EPOLLERR | EPOLLHUP);
+      int read_ev = ep_ev[i].events & (EPOLLIN | EPOLLPRI);
+      int write_ev = ep_ev[i].events & EPOLLOUT;
+      if (read_ev || cancel) {
+        fd_become_readable(exec_ctx, fd, pollset);
+      }
+      if (write_ev || cancel) {
+        fd_become_writable(exec_ctx, fd);
       }
     }
-
-    g_current_thread_polling_island = NULL;
-    gpr_atm_no_barrier_fetch_add(&pi->poller_count, -1);
   }
 
+  g_current_thread_polling_island = NULL;
+  gpr_atm_no_barrier_fetch_add(&pi->poller_count, -1);
+
   GPR_ASSERT(pi != NULL);
 
   /* Before leaving, release the extra ref we added to the polling island. It
@@ -1598,7 +1413,7 @@ static void add_poll_object(grpc_exec_ctx *exec_ctx, poll_obj *bag,
                             poll_obj_type item_type) {
   GPR_TIMER_BEGIN("add_poll_object", 0);
 
-#ifdef PO_DEBUG
+#ifndef NDEBUG
   GPR_ASSERT(item->obj_type == item_type);
   GPR_ASSERT(bag->obj_type == bag_type);
 #endif
@@ -1757,7 +1572,7 @@ static grpc_pollset_set *pollset_set_create(void) {
   grpc_pollset_set *pss = gpr_malloc(sizeof(*pss));
   gpr_mu_init(&pss->po.mu);
   pss->po.pi = NULL;
-#ifdef PO_DEBUG
+#ifndef NDEBUG
   pss->po.obj_type = POLL_OBJ_POLLSET_SET;
 #endif
   return pss;
@@ -1864,7 +1679,6 @@ static const grpc_event_engine_vtable vtable = {
     .fd_notify_on_read = fd_notify_on_read,
     .fd_notify_on_write = fd_notify_on_write,
     .fd_get_read_notifier_pollset = fd_get_read_notifier_pollset,
-    .fd_get_workqueue = fd_get_workqueue,
 
     .pollset_init = pollset_init,
     .pollset_shutdown = pollset_shutdown,
@@ -1882,10 +1696,6 @@ static const grpc_event_engine_vtable vtable = {
     .pollset_set_add_fd = pollset_set_add_fd,
     .pollset_set_del_fd = pollset_set_del_fd,
 
-    .workqueue_ref = workqueue_ref,
-    .workqueue_unref = workqueue_unref,
-    .workqueue_scheduler = workqueue_scheduler,
-
     .shutdown_engine = shutdown_engine,
 };
 
diff --git a/src/core/lib/iomgr/ev_epollsig_linux.h b/src/core/lib/iomgr/ev_epollsig_linux.h
index 9e4034f2a7..88328682b3 100644
--- a/src/core/lib/iomgr/ev_epollsig_linux.h
+++ b/src/core/lib/iomgr/ev_epollsig_linux.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/ev_poll_posix.c b/src/core/lib/iomgr/ev_poll_posix.c
index 19a80ce235..4dc22fbcea 100644
--- a/src/core/lib/iomgr/ev_poll_posix.c
+++ b/src/core/lib/iomgr/ev_poll_posix.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -150,9 +135,7 @@ static void fd_end_poll(grpc_exec_ctx *exec_ctx, grpc_fd_watcher *rec,
 /* Return 1 if this fd is orphaned, 0 otherwise */
 static bool fd_is_orphaned(grpc_fd *fd);
 
-/* Reference counting for fds */
-//#define GRPC_FD_REF_COUNT_DEBUG
-#ifdef GRPC_FD_REF_COUNT_DEBUG
+#ifndef NDEBUG
 static void fd_ref(grpc_fd *fd, const char *reason, const char *file, int line);
 static void fd_unref(grpc_fd *fd, const char *reason, const char *file,
                      int line);
@@ -279,14 +262,17 @@ cv_fd_table g_cvfds;
  * fd_posix.c
  */
 
-#ifdef GRPC_FD_REF_COUNT_DEBUG
+#ifndef NDEBUG
 #define REF_BY(fd, n, reason) ref_by(fd, n, reason, __FILE__, __LINE__)
 #define UNREF_BY(fd, n, reason) unref_by(fd, n, reason, __FILE__, __LINE__)
 static void ref_by(grpc_fd *fd, int n, const char *reason, const char *file,
                    int line) {
-  gpr_log(GPR_DEBUG, "FD %d %p   ref %d %d -> %d [%s; %s:%d]", fd->fd, fd, n,
-          (int)gpr_atm_no_barrier_load(&fd->refst),
-          (int)gpr_atm_no_barrier_load(&fd->refst) + n, reason, file, line);
+  if (GRPC_TRACER_ON(grpc_trace_fd_refcount)) {
+    gpr_log(GPR_DEBUG,
+            "FD %d %p   ref %d %" PRIdPTR " -> %" PRIdPTR " [%s; %s:%d]",
+            fd->fd, fd, n, gpr_atm_no_barrier_load(&fd->refst),
+            gpr_atm_no_barrier_load(&fd->refst) + n, reason, file, line);
+  }
 #else
 #define REF_BY(fd, n, reason) ref_by(fd, n)
 #define UNREF_BY(fd, n, reason) unref_by(fd, n)
@@ -295,18 +281,19 @@ static void ref_by(grpc_fd *fd, int n) {
   GPR_ASSERT(gpr_atm_no_barrier_fetch_add(&fd->refst, n) > 0);
 }
 
-#ifdef GRPC_FD_REF_COUNT_DEBUG
+#ifndef NDEBUG
 static void unref_by(grpc_fd *fd, int n, const char *reason, const char *file,
                      int line) {
-  gpr_atm old;
-  gpr_log(GPR_DEBUG, "FD %d %p unref %d %d -> %d [%s; %s:%d]", fd->fd, fd, n,
-          (int)gpr_atm_no_barrier_load(&fd->refst),
-          (int)gpr_atm_no_barrier_load(&fd->refst) - n, reason, file, line);
+  if (GRPC_TRACER_ON(grpc_trace_fd_refcount)) {
+    gpr_log(GPR_DEBUG,
+            "FD %d %p unref %d %" PRIdPTR " -> %" PRIdPTR " [%s; %s:%d]",
+            fd->fd, fd, n, gpr_atm_no_barrier_load(&fd->refst),
+            gpr_atm_no_barrier_load(&fd->refst) - n, reason, file, line);
+  }
 #else
 static void unref_by(grpc_fd *fd, int n) {
-  gpr_atm old;
 #endif
-  old = gpr_atm_full_fetch_add(&fd->refst, -n);
+  gpr_atm old = gpr_atm_full_fetch_add(&fd->refst, -n);
   if (old == n) {
     gpr_mu_destroy(&fd->mu);
     grpc_iomgr_unregister_object(&fd->iomgr_object);
@@ -337,9 +324,6 @@ static grpc_fd *fd_create(int fd, const char *name) {
   gpr_asprintf(&name2, "%s fd=%d", name, fd);
   grpc_iomgr_register_object(&r->iomgr_object, name2);
   gpr_free(name2);
-#ifdef GRPC_FD_REF_COUNT_DEBUG
-  gpr_log(GPR_DEBUG, "FD %d %p create %s", fd, r, name);
-#endif
   return r;
 }
 
@@ -402,7 +386,7 @@ static void close_fd_locked(grpc_exec_ctx *exec_ctx, grpc_fd *fd) {
   if (!fd->released) {
     close(fd->fd);
   }
-  grpc_closure_sched(exec_ctx, fd->on_done_closure, GRPC_ERROR_NONE);
+  GRPC_CLOSURE_SCHED(exec_ctx, fd->on_done_closure, GRPC_ERROR_NONE);
 }
 
 static int fd_wrapped_fd(grpc_fd *fd) {
@@ -433,7 +417,7 @@ static void fd_orphan(grpc_exec_ctx *exec_ctx, grpc_fd *fd,
 }
 
 /* increment refcount by two to avoid changing the orphan bit */
-#ifdef GRPC_FD_REF_COUNT_DEBUG
+#ifndef NDEBUG
 static void fd_ref(grpc_fd *fd, const char *reason, const char *file,
                    int line) {
   ref_by(fd, 2, reason, file, line);
@@ -461,7 +445,7 @@ static grpc_error *fd_shutdown_error(grpc_fd *fd) {
 static void notify_on_locked(grpc_exec_ctx *exec_ctx, grpc_fd *fd,
                              grpc_closure **st, grpc_closure *closure) {
   if (fd->shutdown) {
-    grpc_closure_sched(exec_ctx, closure,
+    GRPC_CLOSURE_SCHED(exec_ctx, closure,
                        GRPC_ERROR_CREATE_FROM_STATIC_STRING("FD shutdown"));
   } else if (*st == CLOSURE_NOT_READY) {
     /* not ready ==> switch to a waiting state by setting the closure */
@@ -469,7 +453,7 @@ static void notify_on_locked(grpc_exec_ctx *exec_ctx, grpc_fd *fd,
   } else if (*st == CLOSURE_READY) {
     /* already ready ==> queue the closure to run immediately */
     *st = CLOSURE_NOT_READY;
-    grpc_closure_sched(exec_ctx, closure, fd_shutdown_error(fd));
+    GRPC_CLOSURE_SCHED(exec_ctx, closure, fd_shutdown_error(fd));
     maybe_wake_one_watcher_locked(fd);
   } else {
     /* upcallptr was set to a different closure.  This is an error! */
@@ -492,7 +476,7 @@ static int set_ready_locked(grpc_exec_ctx *exec_ctx, grpc_fd *fd,
     return 0;
   } else {
     /* waiting ==> queue closure */
-    grpc_closure_sched(exec_ctx, *st, fd_shutdown_error(fd));
+    GRPC_CLOSURE_SCHED(exec_ctx, *st, fd_shutdown_error(fd));
     *st = CLOSURE_NOT_READY;
     return 1;
   }
@@ -649,8 +633,6 @@ static void fd_end_poll(grpc_exec_ctx *exec_ctx, grpc_fd_watcher *watcher,
   GRPC_FD_UNREF(fd, "poll");
 }
 
-static grpc_workqueue *fd_get_workqueue(grpc_fd *fd) { return NULL; }
-
 /*******************************************************************************
  * pollset_posix.c
  */
@@ -852,7 +834,7 @@ static void finish_shutdown(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset) {
     GRPC_FD_UNREF(pollset->fds[i], "multipoller");
   }
   pollset->fd_count = 0;
-  grpc_closure_sched(exec_ctx, pollset->shutdown_done, GRPC_ERROR_NONE);
+  GRPC_CLOSURE_SCHED(exec_ctx, pollset->shutdown_done, GRPC_ERROR_NONE);
 }
 
 static void work_combine_error(grpc_error **composite, grpc_error *error) {
@@ -901,7 +883,7 @@ static grpc_error *pollset_work(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
   if (!pollset_has_workers(pollset) &&
       !grpc_closure_list_empty(pollset->idle_jobs)) {
     GPR_TIMER_MARK("pollset_work.idle_jobs", 0);
-    grpc_closure_list_sched(exec_ctx, &pollset->idle_jobs);
+    GRPC_CLOSURE_LIST_SCHED(exec_ctx, &pollset->idle_jobs);
     goto done;
   }
   /* If we're shutting down then we don't execute any extended work */
@@ -1071,7 +1053,7 @@ static grpc_error *pollset_work(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
        * TODO(dklempner): Can we refactor the shutdown logic to avoid this? */
       gpr_mu_lock(&pollset->mu);
     } else if (!grpc_closure_list_empty(pollset->idle_jobs)) {
-      grpc_closure_list_sched(exec_ctx, &pollset->idle_jobs);
+      GRPC_CLOSURE_LIST_SCHED(exec_ctx, &pollset->idle_jobs);
       gpr_mu_unlock(&pollset->mu);
       grpc_exec_ctx_flush(exec_ctx);
       gpr_mu_lock(&pollset->mu);
@@ -1090,7 +1072,7 @@ static void pollset_shutdown(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
   pollset->shutdown_done = closure;
   pollset_kick(pollset, GRPC_POLLSET_KICK_BROADCAST);
   if (!pollset_has_workers(pollset)) {
-    grpc_closure_list_sched(exec_ctx, &pollset->idle_jobs);
+    GRPC_CLOSURE_LIST_SCHED(exec_ctx, &pollset->idle_jobs);
   }
   if (!pollset->called_shutdown && !pollset_has_observers(pollset)) {
     pollset->called_shutdown = 1;
@@ -1280,30 +1262,6 @@ static void pollset_set_del_fd(grpc_exec_ctx *exec_ctx,
 }
 
 /*******************************************************************************
- * workqueue stubs
- */
-
-#ifdef GRPC_WORKQUEUE_REFCOUNT_DEBUG
-static grpc_workqueue *workqueue_ref(grpc_workqueue *workqueue,
-                                     const char *file, int line,
-                                     const char *reason) {
-  return workqueue;
-}
-static void workqueue_unref(grpc_exec_ctx *exec_ctx, grpc_workqueue *workqueue,
-                            const char *file, int line, const char *reason) {}
-#else
-static grpc_workqueue *workqueue_ref(grpc_workqueue *workqueue) {
-  return workqueue;
-}
-static void workqueue_unref(grpc_exec_ctx *exec_ctx,
-                            grpc_workqueue *workqueue) {}
-#endif
-
-static grpc_closure_scheduler *workqueue_scheduler(grpc_workqueue *workqueue) {
-  return grpc_schedule_on_exec_ctx;
-}
-
-/*******************************************************************************
  * Condition Variable polling extensions
  */
 
@@ -1520,7 +1478,6 @@ static const grpc_event_engine_vtable vtable = {
     .fd_notify_on_read = fd_notify_on_read,
     .fd_notify_on_write = fd_notify_on_write,
     .fd_get_read_notifier_pollset = fd_get_read_notifier_pollset,
-    .fd_get_workqueue = fd_get_workqueue,
 
     .pollset_init = pollset_init,
     .pollset_shutdown = pollset_shutdown,
@@ -1538,10 +1495,6 @@ static const grpc_event_engine_vtable vtable = {
     .pollset_set_add_fd = pollset_set_add_fd,
     .pollset_set_del_fd = pollset_set_del_fd,
 
-    .workqueue_ref = workqueue_ref,
-    .workqueue_unref = workqueue_unref,
-    .workqueue_scheduler = workqueue_scheduler,
-
     .shutdown_engine = shutdown_engine,
 };
 
diff --git a/src/core/lib/iomgr/ev_poll_posix.h b/src/core/lib/iomgr/ev_poll_posix.h
index 2890e93ead..d444e60944 100644
--- a/src/core/lib/iomgr/ev_poll_posix.h
+++ b/src/core/lib/iomgr/ev_poll_posix.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015-2016, Google Inc.
- * All rights reserved.
+ * Copyright 2015-2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/ev_posix.c b/src/core/lib/iomgr/ev_posix.c
index e79cec640c..682794f527 100644
--- a/src/core/lib/iomgr/ev_posix.c
+++ b/src/core/lib/iomgr/ev_posix.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -54,7 +39,12 @@
 #include "src/core/lib/support/env.h"
 
 grpc_tracer_flag grpc_polling_trace =
-    GRPC_TRACER_INITIALIZER(false); /* Disabled by default */
+    GRPC_TRACER_INITIALIZER(false, "polling"); /* Disabled by default */
+
+#ifndef NDEBUG
+grpc_tracer_flag grpc_trace_fd_refcount =
+    GRPC_TRACER_INITIALIZER(false, "fd_refcount");
+#endif
 
 /** Default poll() function - a pointer so that it can be overridden by some
  *  tests */
@@ -74,13 +64,13 @@ typedef struct {
 } event_engine_factory;
 
 static const event_engine_factory g_factories[] = {
-    {"epollex", grpc_init_epollex_linux},
     {"epollsig", grpc_init_epollsig_linux},
     {"epoll1", grpc_init_epoll1_linux},
     {"epoll-threadpool", grpc_init_epoll_thread_pool_linux},
     {"epoll-limited", grpc_init_epoll_limited_pollers_linux},
     {"poll", grpc_init_poll_posix},
     {"poll-cv", grpc_init_poll_cv_posix},
+    {"epollex", grpc_init_epollex_linux},
 };
 
 static void add(const char *beg, const char *end, char ***ss, size_t *ns) {
@@ -131,11 +121,15 @@ void grpc_set_event_engine_test_only(
   g_event_engine = ev_engine;
 }
 
+const grpc_event_engine_vtable *grpc_get_event_engine_test_only() {
+  return g_event_engine;
+}
+
 /* Call this only after calling grpc_event_engine_init() */
 const char *grpc_get_poll_strategy_name() { return g_poll_strategy_name; }
 
 void grpc_event_engine_init(void) {
-  grpc_register_tracer("polling", &grpc_polling_trace);
+  grpc_register_tracer(&grpc_polling_trace);
 
   char *s = gpr_getenv("GRPC_POLL_STRATEGY");
   if (s == NULL) {
@@ -171,10 +165,6 @@ grpc_fd *grpc_fd_create(int fd, const char *name) {
   return g_event_engine->fd_create(fd, name);
 }
 
-grpc_workqueue *grpc_fd_get_workqueue(grpc_fd *fd) {
-  return g_event_engine->fd_get_workqueue(fd);
-}
-
 int grpc_fd_wrapped_fd(grpc_fd *fd) {
   return g_event_engine->fd_wrapped_fd(fd);
 }
@@ -276,26 +266,4 @@ void grpc_pollset_set_del_fd(grpc_exec_ctx *exec_ctx,
   g_event_engine->pollset_set_del_fd(exec_ctx, pollset_set, fd);
 }
 
-#ifdef GRPC_WORKQUEUE_REFCOUNT_DEBUG
-grpc_workqueue *grpc_workqueue_ref(grpc_workqueue *workqueue, const char *file,
-                                   int line, const char *reason) {
-  return g_event_engine->workqueue_ref(workqueue, file, line, reason);
-}
-void grpc_workqueue_unref(grpc_exec_ctx *exec_ctx, grpc_workqueue *workqueue,
-                          const char *file, int line, const char *reason) {
-  g_event_engine->workqueue_unref(exec_ctx, workqueue, file, line, reason);
-}
-#else
-grpc_workqueue *grpc_workqueue_ref(grpc_workqueue *workqueue) {
-  return g_event_engine->workqueue_ref(workqueue);
-}
-void grpc_workqueue_unref(grpc_exec_ctx *exec_ctx, grpc_workqueue *workqueue) {
-  g_event_engine->workqueue_unref(exec_ctx, workqueue);
-}
-#endif
-
-grpc_closure_scheduler *grpc_workqueue_scheduler(grpc_workqueue *workqueue) {
-  return g_event_engine->workqueue_scheduler(workqueue);
-}
-
 #endif  // GRPC_POSIX_SOCKET
diff --git a/src/core/lib/iomgr/ev_posix.h b/src/core/lib/iomgr/ev_posix.h
index e505e70412..21279877e8 100644
--- a/src/core/lib/iomgr/ev_posix.h
+++ b/src/core/lib/iomgr/ev_posix.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -41,7 +26,6 @@
 #include "src/core/lib/iomgr/pollset.h"
 #include "src/core/lib/iomgr/pollset_set.h"
 #include "src/core/lib/iomgr/wakeup_fd_posix.h"
-#include "src/core/lib/iomgr/workqueue.h"
 
 extern grpc_tracer_flag grpc_polling_trace; /* Disabled by default */
 
@@ -60,7 +44,6 @@ typedef struct grpc_event_engine_vtable {
   void (*fd_notify_on_write)(grpc_exec_ctx *exec_ctx, grpc_fd *fd,
                              grpc_closure *closure);
   bool (*fd_is_shutdown)(grpc_fd *fd);
-  grpc_workqueue *(*fd_get_workqueue)(grpc_fd *fd);
   grpc_pollset *(*fd_get_read_notifier_pollset)(grpc_exec_ctx *exec_ctx,
                                                 grpc_fd *fd);
 
@@ -97,17 +80,6 @@ typedef struct grpc_event_engine_vtable {
                              grpc_pollset_set *pollset_set, grpc_fd *fd);
 
   void (*shutdown_engine)(void);
-
-#ifdef GRPC_WORKQUEUE_REFCOUNT_DEBUG
-  grpc_workqueue *(*workqueue_ref)(grpc_workqueue *workqueue, const char *file,
-                                   int line, const char *reason);
-  void (*workqueue_unref)(grpc_exec_ctx *exec_ctx, grpc_workqueue *workqueue,
-                          const char *file, int line, const char *reason);
-#else
-  grpc_workqueue *(*workqueue_ref)(grpc_workqueue *workqueue);
-  void (*workqueue_unref)(grpc_exec_ctx *exec_ctx, grpc_workqueue *workqueue);
-#endif
-  grpc_closure_scheduler *(*workqueue_scheduler)(grpc_workqueue *workqueue);
 } grpc_event_engine_vtable;
 
 void grpc_event_engine_init(void);
@@ -121,9 +93,6 @@ const char *grpc_get_poll_strategy_name();
    This takes ownership of closing fd. */
 grpc_fd *grpc_fd_create(int fd, const char *name);
 
-/* Get a workqueue that's associated with this fd */
-grpc_workqueue *grpc_fd_get_workqueue(grpc_fd *fd);
-
 /* Return the wrapped fd, or -1 if it has been released or closed. */
 int grpc_fd_wrapped_fd(grpc_fd *fd);
 
@@ -184,7 +153,9 @@ void grpc_pollset_set_del_fd(grpc_exec_ctx *exec_ctx,
 typedef int (*grpc_poll_function_type)(struct pollfd *, nfds_t, int);
 extern grpc_poll_function_type grpc_poll_function;
 
-/* This should be used for testing purposes ONLY */
+/* WARNING: The following two functions should be used for testing purposes
+ * ONLY */
 void grpc_set_event_engine_test_only(const grpc_event_engine_vtable *);
+const grpc_event_engine_vtable *grpc_get_event_engine_test_only();
 
 #endif /* GRPC_CORE_LIB_IOMGR_EV_POSIX_H */
diff --git a/src/core/lib/iomgr/ev_windows.c b/src/core/lib/iomgr/ev_windows.c
new file mode 100644
index 0000000000..c24dfaeaf7
--- /dev/null
+++ b/src/core/lib/iomgr/ev_windows.c
@@ -0,0 +1,28 @@
+/*
+ *
+ * Copyright 2015 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+#include "src/core/lib/iomgr/port.h"
+
+#ifdef GRPC_WINSOCK_SOCKET
+
+#include "src/core/lib/debug/trace.h"
+
+grpc_tracer_flag grpc_polling_trace =
+    GRPC_TRACER_INITIALIZER(false, "polling"); /* Disabled by default */
+
+#endif  // GRPC_WINSOCK_SOCKET
diff --git a/src/core/lib/iomgr/exec_ctx.c b/src/core/lib/iomgr/exec_ctx.c
index 3423379e8d..5d2fc4af86 100644
--- a/src/core/lib/iomgr/exec_ctx.c
+++ b/src/core/lib/iomgr/exec_ctx.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -38,7 +23,6 @@
 #include <grpc/support/thd.h>
 
 #include "src/core/lib/iomgr/combiner.h"
-#include "src/core/lib/iomgr/workqueue.h"
 #include "src/core/lib/profiling/timers.h"
 
 bool grpc_exec_ctx_ready_to_finish(grpc_exec_ctx *exec_ctx) {
@@ -103,8 +87,19 @@ static void exec_ctx_run(grpc_exec_ctx *exec_ctx, grpc_closure *closure,
                          grpc_error *error) {
 #ifndef NDEBUG
   closure->scheduled = false;
+  if (GRPC_TRACER_ON(grpc_trace_closure)) {
+    gpr_log(GPR_DEBUG, "running closure %p: created [%s:%d]: %s [%s:%d]",
+            closure, closure->file_created, closure->line_created,
+            closure->run ? "run" : "scheduled", closure->file_initiated,
+            closure->line_initiated);
+  }
 #endif
   closure->cb(exec_ctx, closure->cb_arg, error);
+#ifndef NDEBUG
+  if (GRPC_TRACER_ON(grpc_trace_closure)) {
+    gpr_log(GPR_DEBUG, "closure %p finished", closure);
+  }
+#endif
   GRPC_ERROR_UNREF(error);
 }
 
diff --git a/src/core/lib/iomgr/exec_ctx.h b/src/core/lib/iomgr/exec_ctx.h
index 26da4d0a73..8e030bf741 100644
--- a/src/core/lib/iomgr/exec_ctx.h
+++ b/src/core/lib/iomgr/exec_ctx.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/executor.c b/src/core/lib/iomgr/executor.c
index 75fd5b1c50..7621a7fe75 100644
--- a/src/core/lib/iomgr/executor.c
+++ b/src/core/lib/iomgr/executor.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -36,132 +21,172 @@
 #include <string.h>
 
 #include <grpc/support/alloc.h>
+#include <grpc/support/cpu.h>
 #include <grpc/support/log.h>
 #include <grpc/support/sync.h>
 #include <grpc/support/thd.h>
+#include <grpc/support/tls.h>
+#include <grpc/support/useful.h>
+
 #include "src/core/lib/iomgr/exec_ctx.h"
+#include "src/core/lib/support/spinlock.h"
+
+#define MAX_DEPTH 2
 
-typedef struct grpc_executor_data {
-  int busy;          /**< is the thread currently running? */
-  int shutting_down; /**< has \a grpc_shutdown() been invoked? */
-  int pending_join;  /**< has the thread finished but not been joined? */
-  grpc_closure_list closures; /**< collection of pending work */
-  gpr_thd_id tid; /**< thread id of the thread, only valid if \a busy or \a
-                     pending_join are true */
-  gpr_thd_options options;
+typedef struct {
   gpr_mu mu;
-} grpc_executor;
+  gpr_cv cv;
+  grpc_closure_list elems;
+  size_t depth;
+  bool shutdown;
+  gpr_thd_id id;
+} thread_state;
 
-static grpc_executor g_executor;
+static thread_state *g_thread_state;
+static size_t g_max_threads;
+static gpr_atm g_cur_threads;
+static gpr_spinlock g_adding_thread_lock = GPR_SPINLOCK_STATIC_INITIALIZER;
 
-void grpc_executor_init() {
-  memset(&g_executor, 0, sizeof(grpc_executor));
-  gpr_mu_init(&g_executor.mu);
-  g_executor.options = gpr_thd_options_default();
-  gpr_thd_options_set_joinable(&g_executor.options);
-}
+GPR_TLS_DECL(g_this_thread_state);
 
-/* thread body */
-static void closure_exec_thread_func(void *ignored) {
-  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
-  while (1) {
-    gpr_mu_lock(&g_executor.mu);
-    if (g_executor.shutting_down != 0) {
-      gpr_mu_unlock(&g_executor.mu);
-      break;
-    }
-    if (grpc_closure_list_empty(g_executor.closures)) {
-      /* no more work, time to die */
-      GPR_ASSERT(g_executor.busy == 1);
-      g_executor.busy = 0;
-      gpr_mu_unlock(&g_executor.mu);
-      break;
-    } else {
-      grpc_closure *c = g_executor.closures.head;
-      grpc_closure_list_init(&g_executor.closures);
-      gpr_mu_unlock(&g_executor.mu);
-      while (c != NULL) {
-        grpc_closure *next = c->next_data.next;
-        grpc_error *error = c->error_data.error;
+static void executor_thread(void *arg);
+
+static size_t run_closures(grpc_exec_ctx *exec_ctx, grpc_closure_list list) {
+  size_t n = 0;
+
+  grpc_closure *c = list.head;
+  while (c != NULL) {
+    grpc_closure *next = c->next_data.next;
+    grpc_error *error = c->error_data.error;
 #ifndef NDEBUG
-        c->scheduled = false;
+    c->scheduled = false;
 #endif
-        c->cb(&exec_ctx, c->cb_arg, error);
-        GRPC_ERROR_UNREF(error);
-        c = next;
-      }
-      grpc_exec_ctx_flush(&exec_ctx);
-    }
+    c->cb(exec_ctx, c->cb_arg, error);
+    GRPC_ERROR_UNREF(error);
+    c = next;
+    n++;
   }
-  grpc_exec_ctx_finish(&exec_ctx);
+
+  return n;
 }
 
-/* Spawn the thread if new work has arrived a no thread is up */
-static void maybe_spawn_locked() {
-  if (grpc_closure_list_empty(g_executor.closures) == 1) {
-    return;
-  }
-  if (g_executor.shutting_down == 1) {
-    return;
-  }
+bool grpc_executor_is_threaded() {
+  return gpr_atm_no_barrier_load(&g_cur_threads) > 0;
+}
 
-  if (g_executor.busy != 0) {
-    /* Thread still working. New work will be picked up by already running
-     * thread. Not spawning anything. */
-    return;
-  } else if (g_executor.pending_join != 0) {
-    /* Pickup the remains of the previous incarnations of the thread. */
-    gpr_thd_join(g_executor.tid);
-    g_executor.pending_join = 0;
+void grpc_executor_set_threading(grpc_exec_ctx *exec_ctx, bool threading) {
+  gpr_atm cur_threads = gpr_atm_no_barrier_load(&g_cur_threads);
+  if (threading) {
+    if (cur_threads > 0) return;
+    g_max_threads = GPR_MAX(1, 2 * gpr_cpu_num_cores());
+    gpr_atm_no_barrier_store(&g_cur_threads, 1);
+    gpr_tls_init(&g_this_thread_state);
+    g_thread_state = gpr_zalloc(sizeof(thread_state) * g_max_threads);
+    for (size_t i = 0; i < g_max_threads; i++) {
+      gpr_mu_init(&g_thread_state[i].mu);
+      gpr_cv_init(&g_thread_state[i].cv);
+      g_thread_state[i].elems = (grpc_closure_list)GRPC_CLOSURE_LIST_INIT;
+    }
+
+    gpr_thd_options opt = gpr_thd_options_default();
+    gpr_thd_options_set_joinable(&opt);
+    gpr_thd_new(&g_thread_state[0].id, executor_thread, &g_thread_state[0],
+                &opt);
+  } else {
+    if (cur_threads == 0) return;
+    for (size_t i = 0; i < g_max_threads; i++) {
+      gpr_mu_lock(&g_thread_state[i].mu);
+      g_thread_state[i].shutdown = true;
+      gpr_cv_signal(&g_thread_state[i].cv);
+      gpr_mu_unlock(&g_thread_state[i].mu);
+    }
+    /* ensure no thread is adding a new thread... once this is past, then
+       no thread will try to add a new one either (since shutdown is true) */
+    gpr_spinlock_lock(&g_adding_thread_lock);
+    gpr_spinlock_unlock(&g_adding_thread_lock);
+    for (gpr_atm i = 0; i < g_cur_threads; i++) {
+      gpr_thd_join(g_thread_state[i].id);
+    }
+    gpr_atm_no_barrier_store(&g_cur_threads, 0);
+    for (size_t i = 0; i < g_max_threads; i++) {
+      gpr_mu_destroy(&g_thread_state[i].mu);
+      gpr_cv_destroy(&g_thread_state[i].cv);
+      run_closures(exec_ctx, g_thread_state[i].elems);
+    }
+    gpr_free(g_thread_state);
+    gpr_tls_destroy(&g_this_thread_state);
   }
+}
 
-  /* All previous instances of the thread should have been joined at this point.
-   * Spawn time! */
-  g_executor.busy = 1;
-  GPR_ASSERT(gpr_thd_new(&g_executor.tid, closure_exec_thread_func, NULL,
-                         &g_executor.options));
-  g_executor.pending_join = 1;
+void grpc_executor_init(grpc_exec_ctx *exec_ctx) {
+  gpr_atm_no_barrier_store(&g_cur_threads, 0);
+  grpc_executor_set_threading(exec_ctx, true);
 }
 
-static void executor_push(grpc_exec_ctx *exec_ctx, grpc_closure *closure,
-                          grpc_error *error) {
-  gpr_mu_lock(&g_executor.mu);
-  if (g_executor.shutting_down == 0) {
-    grpc_closure_list_append(&g_executor.closures, closure, error);
-    maybe_spawn_locked();
+void grpc_executor_shutdown(grpc_exec_ctx *exec_ctx) {
+  grpc_executor_set_threading(exec_ctx, false);
+}
+
+static void executor_thread(void *arg) {
+  thread_state *ts = arg;
+  gpr_tls_set(&g_this_thread_state, (intptr_t)ts);
+
+  grpc_exec_ctx exec_ctx =
+      GRPC_EXEC_CTX_INITIALIZER(0, grpc_never_ready_to_finish, NULL);
+
+  size_t subtract_depth = 0;
+  for (;;) {
+    gpr_mu_lock(&ts->mu);
+    ts->depth -= subtract_depth;
+    while (grpc_closure_list_empty(ts->elems) && !ts->shutdown) {
+      gpr_cv_wait(&ts->cv, &ts->mu, gpr_inf_future(GPR_CLOCK_REALTIME));
+    }
+    if (ts->shutdown) {
+      gpr_mu_unlock(&ts->mu);
+      break;
+    }
+    grpc_closure_list exec = ts->elems;
+    ts->elems = (grpc_closure_list)GRPC_CLOSURE_LIST_INIT;
+    gpr_mu_unlock(&ts->mu);
+
+    subtract_depth = run_closures(&exec_ctx, exec);
+    grpc_exec_ctx_flush(&exec_ctx);
   }
-  gpr_mu_unlock(&g_executor.mu);
+  grpc_exec_ctx_finish(&exec_ctx);
 }
 
-void grpc_executor_shutdown(grpc_exec_ctx *exec_ctx) {
-  int pending_join;
-
-  gpr_mu_lock(&g_executor.mu);
-  pending_join = g_executor.pending_join;
-  g_executor.shutting_down = 1;
-  gpr_mu_unlock(&g_executor.mu);
-  /* we can release the lock at this point despite the access to the closure
-   * list below because we aren't accepting new work */
-
-  /* Execute pending callbacks, some may be performing cleanups */
-  grpc_closure *c = g_executor.closures.head;
-  grpc_closure_list_init(&g_executor.closures);
-  while (c != NULL) {
-    grpc_closure *next = c->next_data.next;
-    grpc_error *error = c->error_data.error;
-#ifndef NDEBUG
-    c->scheduled = false;
-#endif
-    c->cb(exec_ctx, c->cb_arg, error);
-    GRPC_ERROR_UNREF(error);
-    c = next;
+static void executor_push(grpc_exec_ctx *exec_ctx, grpc_closure *closure,
+                          grpc_error *error) {
+  size_t cur_thread_count = (size_t)gpr_atm_no_barrier_load(&g_cur_threads);
+  if (cur_thread_count == 0) {
+    grpc_closure_list_append(&exec_ctx->closure_list, closure, error);
+    return;
+  }
+  thread_state *ts = (thread_state *)gpr_tls_get(&g_this_thread_state);
+  if (ts == NULL) {
+    ts = &g_thread_state[GPR_HASH_POINTER(exec_ctx, cur_thread_count)];
   }
-  grpc_exec_ctx_flush(exec_ctx);
-  GPR_ASSERT(grpc_closure_list_empty(g_executor.closures));
-  if (pending_join) {
-    gpr_thd_join(g_executor.tid);
+  gpr_mu_lock(&ts->mu);
+  if (grpc_closure_list_empty(ts->elems)) {
+    gpr_cv_signal(&ts->cv);
+  }
+  grpc_closure_list_append(&ts->elems, closure, error);
+  ts->depth++;
+  bool try_new_thread = ts->depth > MAX_DEPTH &&
+                        cur_thread_count < g_max_threads && !ts->shutdown;
+  gpr_mu_unlock(&ts->mu);
+  if (try_new_thread && gpr_spinlock_trylock(&g_adding_thread_lock)) {
+    cur_thread_count = (size_t)gpr_atm_no_barrier_load(&g_cur_threads);
+    if (cur_thread_count < g_max_threads) {
+      gpr_atm_no_barrier_store(&g_cur_threads, cur_thread_count + 1);
+
+      gpr_thd_options opt = gpr_thd_options_default();
+      gpr_thd_options_set_joinable(&opt);
+      gpr_thd_new(&g_thread_state[cur_thread_count].id, executor_thread,
+                  &g_thread_state[cur_thread_count], &opt);
+    }
+    gpr_spinlock_unlock(&g_adding_thread_lock);
   }
-  gpr_mu_destroy(&g_executor.mu);
 }
 
 static const grpc_closure_scheduler_vtable executor_vtable = {
diff --git a/src/core/lib/iomgr/executor.h b/src/core/lib/iomgr/executor.h
index 1213016383..c3382a0a12 100644
--- a/src/core/lib/iomgr/executor.h
+++ b/src/core/lib/iomgr/executor.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -41,11 +26,18 @@
  * This mechanism is meant to outsource work (grpc_closure instances) to a
  * thread, for those cases where blocking isn't an option but there isn't a
  * non-blocking solution available. */
-void grpc_executor_init();
+void grpc_executor_init(grpc_exec_ctx *exec_ctx);
 
 extern grpc_closure_scheduler *grpc_executor_scheduler;
 
 /** Shutdown the executor, running all pending work as part of the call */
 void grpc_executor_shutdown(grpc_exec_ctx *exec_ctx);
 
+/** Is the executor multi-threaded? */
+bool grpc_executor_is_threaded();
+
+/* enable/disable threading - must be called after grpc_executor_init and before
+   grpc_executor_shutdown */
+void grpc_executor_set_threading(grpc_exec_ctx *exec_ctx, bool enable);
+
 #endif /* GRPC_CORE_LIB_IOMGR_EXECUTOR_H */
diff --git a/src/core/lib/iomgr/iocp_windows.c b/src/core/lib/iomgr/iocp_windows.c
index f0f4a6ff39..e343f8a794 100644
--- a/src/core/lib/iomgr/iocp_windows.c
+++ b/src/core/lib/iomgr/iocp_windows.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/iocp_windows.h b/src/core/lib/iomgr/iocp_windows.h
index 011fee38ff..9c89e868c5 100644
--- a/src/core/lib/iomgr/iocp_windows.h
+++ b/src/core/lib/iomgr/iocp_windows.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/iomgr.c b/src/core/lib/iomgr/iomgr.c
index bdee4b3e52..5e15b01ffd 100644
--- a/src/core/lib/iomgr/iomgr.c
+++ b/src/core/lib/iomgr/iomgr.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -44,6 +29,7 @@
 #include <grpc/support/useful.h>
 
 #include "src/core/lib/iomgr/exec_ctx.h"
+#include "src/core/lib/iomgr/executor.h"
 #include "src/core/lib/iomgr/iomgr_internal.h"
 #include "src/core/lib/iomgr/network_status_tracker.h"
 #include "src/core/lib/iomgr/timer.h"
@@ -56,21 +42,26 @@ static gpr_cv g_rcv;
 static int g_shutdown;
 static grpc_iomgr_object g_root_object;
 
-void grpc_iomgr_init(void) {
+void grpc_iomgr_init(grpc_exec_ctx *exec_ctx) {
   g_shutdown = 0;
   gpr_mu_init(&g_mu);
   gpr_cv_init(&g_rcv);
   grpc_exec_ctx_global_init();
+<<<<<<< HEAD
   grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
   grpc_timer_list_init(&exec_ctx);
   grpc_exec_ctx_finish(&exec_ctx);
+=======
+  grpc_executor_init(exec_ctx);
+  grpc_timer_list_init(gpr_now(GPR_CLOCK_MONOTONIC));
+>>>>>>> 4708a21c8144f9fed3c90ea8fa153aa20302a1d7
   g_root_object.next = g_root_object.prev = &g_root_object;
   g_root_object.name = "root";
   grpc_network_status_init();
   grpc_iomgr_platform_init();
 }
 
-void grpc_iomgr_start(void) { grpc_timer_manager_init(); }
+void grpc_iomgr_start(grpc_exec_ctx *exec_ctx) { grpc_timer_manager_init(); }
 
 static size_t count_objects(void) {
   grpc_iomgr_object *obj;
@@ -95,6 +86,7 @@ void grpc_iomgr_shutdown(grpc_exec_ctx *exec_ctx) {
 
   grpc_timer_manager_shutdown();
   grpc_iomgr_platform_flush();
+  grpc_executor_shutdown(exec_ctx);
 
   gpr_mu_lock(&g_mu);
   g_shutdown = 1;
@@ -111,7 +103,7 @@ void grpc_iomgr_shutdown(grpc_exec_ctx *exec_ctx) {
     }
     exec_ctx->now_is_valid = true;
     exec_ctx->now = GRPC_MILLIS_INF_FUTURE;
-    if (grpc_timer_check(exec_ctx, NULL)) {
+    if (grpc_timer_check(exec_ctx, NULL) == GRPC_TIMERS_FIRED) {
       gpr_mu_unlock(&g_mu);
       grpc_exec_ctx_flush(exec_ctx);
       grpc_iomgr_platform_flush();
diff --git a/src/core/lib/iomgr/iomgr.h b/src/core/lib/iomgr/iomgr.h
index 6e2e023615..e3cd6ebe79 100644
--- a/src/core/lib/iomgr/iomgr.h
+++ b/src/core/lib/iomgr/iomgr.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -38,10 +23,10 @@
 #include "src/core/lib/iomgr/port.h"
 
 /** Initializes the iomgr. */
-void grpc_iomgr_init(void);
+void grpc_iomgr_init(grpc_exec_ctx *exec_ctx);
 
 /** Starts any background threads for iomgr. */
-void grpc_iomgr_start(void);
+void grpc_iomgr_start(grpc_exec_ctx *exec_ctx);
 
 /** Signals the intention to shutdown the iomgr. Expects to be able to flush
  * exec_ctx. */
diff --git a/src/core/lib/iomgr/iomgr_internal.h b/src/core/lib/iomgr/iomgr_internal.h
index 805be1f1e4..836d82515d 100644
--- a/src/core/lib/iomgr/iomgr_internal.h
+++ b/src/core/lib/iomgr/iomgr_internal.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/iomgr_posix.c b/src/core/lib/iomgr/iomgr_posix.c
index f5ee0c9ee4..f5875a247e 100644
--- a/src/core/lib/iomgr/iomgr_posix.c
+++ b/src/core/lib/iomgr/iomgr_posix.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -43,7 +28,7 @@
 void grpc_iomgr_platform_init(void) {
   grpc_wakeup_fd_global_init();
   grpc_event_engine_init();
-  grpc_register_tracer("tcp", &grpc_tcp_trace);
+  grpc_register_tracer(&grpc_tcp_trace);
 }
 
 void grpc_iomgr_platform_flush(void) {}
diff --git a/src/core/lib/iomgr/iomgr_posix.h b/src/core/lib/iomgr/iomgr_posix.h
index d5eade962a..f7a4af6a89 100644
--- a/src/core/lib/iomgr/iomgr_posix.h
+++ b/src/core/lib/iomgr/iomgr_posix.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/iomgr_uv.c b/src/core/lib/iomgr/iomgr_uv.c
index 96516ff167..8b1245c640 100644
--- a/src/core/lib/iomgr/iomgr_uv.c
+++ b/src/core/lib/iomgr/iomgr_uv.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -41,7 +26,7 @@
 
 void grpc_iomgr_platform_init(void) {
   grpc_pollset_global_init();
-  grpc_register_tracer("tcp", &grpc_tcp_trace);
+  grpc_register_tracer(&grpc_tcp_trace);
 }
 void grpc_iomgr_platform_flush(void) {}
 void grpc_iomgr_platform_shutdown(void) { grpc_pollset_global_shutdown(); }
diff --git a/src/core/lib/iomgr/iomgr_windows.c b/src/core/lib/iomgr/iomgr_windows.c
index b659264ede..630370166d 100644
--- a/src/core/lib/iomgr/iomgr_windows.c
+++ b/src/core/lib/iomgr/iomgr_windows.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/is_epollexclusive_available.c b/src/core/lib/iomgr/is_epollexclusive_available.c
index 34fcf313e5..e8a7d4d52c 100644
--- a/src/core/lib/iomgr/is_epollexclusive_available.c
+++ b/src/core/lib/iomgr/is_epollexclusive_available.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2017, Google Inc.
- * All rights reserved.
+ * Copyright 2017 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/is_epollexclusive_available.h b/src/core/lib/iomgr/is_epollexclusive_available.h
index b65b819e74..1d2e133a3b 100644
--- a/src/core/lib/iomgr/is_epollexclusive_available.h
+++ b/src/core/lib/iomgr/is_epollexclusive_available.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/load_file.c b/src/core/lib/iomgr/load_file.c
index 208f74e20c..ba77a52afc 100644
--- a/src/core/lib/iomgr/load_file.c
+++ b/src/core/lib/iomgr/load_file.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/load_file.h b/src/core/lib/iomgr/load_file.h
index 73ee8c3abf..db1ffb3d63 100644
--- a/src/core/lib/iomgr/load_file.h
+++ b/src/core/lib/iomgr/load_file.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/lockfree_event.c b/src/core/lib/iomgr/lockfree_event.c
index 898ec1cb1b..c2ceecb3c5 100644
--- a/src/core/lib/iomgr/lockfree_event.c
+++ b/src/core/lib/iomgr/lockfree_event.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2017, Google Inc.
- * All rights reserved.
+ * Copyright 2017 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -127,7 +112,7 @@ void grpc_lfev_notify_on(grpc_exec_ctx *exec_ctx, gpr_atm *state,
            closure when transitioning out of CLOSURE_NO_READY state (i.e there
            is no other code that needs to 'happen-after' this) */
         if (gpr_atm_no_barrier_cas(state, CLOSURE_READY, CLOSURE_NOT_READY)) {
-          grpc_closure_sched(exec_ctx, closure, GRPC_ERROR_NONE);
+          GRPC_CLOSURE_SCHED(exec_ctx, closure, GRPC_ERROR_NONE);
           return; /* Successful. Return */
         }
 
@@ -140,7 +125,7 @@ void grpc_lfev_notify_on(grpc_exec_ctx *exec_ctx, gpr_atm *state,
            schedule the closure with the shutdown error */
         if ((curr & FD_SHUTDOWN_BIT) > 0) {
           grpc_error *shutdown_err = (grpc_error *)(curr & ~FD_SHUTDOWN_BIT);
-          grpc_closure_sched(exec_ctx, closure,
+          GRPC_CLOSURE_SCHED(exec_ctx, closure,
                              GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
                                  "FD Shutdown", &shutdown_err, 1));
           return;
@@ -192,7 +177,7 @@ bool grpc_lfev_set_shutdown(grpc_exec_ctx *exec_ctx, gpr_atm *state,
            happens-after on that edge), and a release to pair with anything
            loading the shutdown state. */
         if (gpr_atm_full_cas(state, curr, new_state)) {
-          grpc_closure_sched(exec_ctx, (grpc_closure *)curr,
+          GRPC_CLOSURE_SCHED(exec_ctx, (grpc_closure *)curr,
                              GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
                                  "FD Shutdown", &shutdown_err, 1));
           return true;
@@ -241,7 +226,7 @@ void grpc_lfev_set_ready(grpc_exec_ctx *exec_ctx, gpr_atm *state) {
            spurious set_ready; release pairs with this or the acquire in
            notify_on (or set_shutdown) */
         else if (gpr_atm_full_cas(state, curr, CLOSURE_NOT_READY)) {
-          grpc_closure_sched(exec_ctx, (grpc_closure *)curr, GRPC_ERROR_NONE);
+          GRPC_CLOSURE_SCHED(exec_ctx, (grpc_closure *)curr, GRPC_ERROR_NONE);
           return;
         }
         /* else the state changed again (only possible by either a racing
diff --git a/src/core/lib/iomgr/lockfree_event.h b/src/core/lib/iomgr/lockfree_event.h
index 1d9119204c..ef3844a07a 100644
--- a/src/core/lib/iomgr/lockfree_event.h
+++ b/src/core/lib/iomgr/lockfree_event.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2017, Google Inc.
- * All rights reserved.
+ * Copyright 2017 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/network_status_tracker.c b/src/core/lib/iomgr/network_status_tracker.c
index 4104bf927a..4e5c1d5408 100644
--- a/src/core/lib/iomgr/network_status_tracker.c
+++ b/src/core/lib/iomgr/network_status_tracker.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/network_status_tracker.h b/src/core/lib/iomgr/network_status_tracker.h
index 67cb645f44..c0295c1f74 100644
--- a/src/core/lib/iomgr/network_status_tracker.h
+++ b/src/core/lib/iomgr/network_status_tracker.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/polling_entity.c b/src/core/lib/iomgr/polling_entity.c
index d1686aa12f..74d8794af5 100644
--- a/src/core/lib/iomgr/polling_entity.c
+++ b/src/core/lib/iomgr/polling_entity.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/polling_entity.h b/src/core/lib/iomgr/polling_entity.h
index e81531053c..971fd88b42 100644
--- a/src/core/lib/iomgr/polling_entity.h
+++ b/src/core/lib/iomgr/polling_entity.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -38,9 +23,8 @@
 #include "src/core/lib/iomgr/pollset_set.h"
 
 /* A grpc_polling_entity is a pollset-or-pollset_set container. It allows
- * functions that
- * accept a pollset XOR a pollset_set to do so through an abstract interface.
- * No ownership is taken. */
+ * functions that accept a pollset XOR a pollset_set to do so through an
+ * abstract interface. No ownership is taken. */
 
 typedef struct grpc_polling_entity {
   union {
@@ -64,18 +48,14 @@ grpc_pollset_set *grpc_polling_entity_pollset_set(grpc_polling_entity *pollent);
 bool grpc_polling_entity_is_empty(const grpc_polling_entity *pollent);
 
 /** Add the pollset or pollset_set in \a pollent to the destination pollset_set
- * \a
- * pss_dst */
+ * \a * pss_dst */
 void grpc_polling_entity_add_to_pollset_set(grpc_exec_ctx *exec_ctx,
                                             grpc_polling_entity *pollent,
                                             grpc_pollset_set *pss_dst);
 
 /** Delete the pollset or pollset_set in \a pollent from the destination
- * pollset_set \a
- * pss_dst */
+ * pollset_set \a * pss_dst */
 void grpc_polling_entity_del_from_pollset_set(grpc_exec_ctx *exec_ctx,
                                               grpc_polling_entity *pollent,
                                               grpc_pollset_set *pss_dst);
-/* pollset_set specific */
-
 #endif /* GRPC_CORE_LIB_IOMGR_POLLING_ENTITY_H */
diff --git a/src/core/lib/iomgr/pollset.h b/src/core/lib/iomgr/pollset.h
index e771ecf7a5..49d4251894 100644
--- a/src/core/lib/iomgr/pollset.h
+++ b/src/core/lib/iomgr/pollset.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -40,6 +25,10 @@
 
 #include "src/core/lib/iomgr/exec_ctx.h"
 
+#ifndef NDEBUG
+extern grpc_tracer_flag grpc_trace_fd_refcount;
+#endif
+
 /* A grpc_pollset is a set of file descriptors that a higher level item is
    interested in. For example:
     - a server will typically keep a pollset containing all connected channels,
diff --git a/src/core/lib/iomgr/pollset_set.h b/src/core/lib/iomgr/pollset_set.h
index d11801d63b..29c0f03561 100644
--- a/src/core/lib/iomgr/pollset_set.h
+++ b/src/core/lib/iomgr/pollset_set.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/pollset_set_uv.c b/src/core/lib/iomgr/pollset_set_uv.c
index 836cfee4ef..90186edbb7 100644
--- a/src/core/lib/iomgr/pollset_set_uv.c
+++ b/src/core/lib/iomgr/pollset_set_uv.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/pollset_set_windows.c b/src/core/lib/iomgr/pollset_set_windows.c
index ae18c8a3ce..2105a47ad4 100644
--- a/src/core/lib/iomgr/pollset_set_windows.c
+++ b/src/core/lib/iomgr/pollset_set_windows.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/pollset_set_windows.h b/src/core/lib/iomgr/pollset_set_windows.h
index 0356749b15..1173f760a0 100644
--- a/src/core/lib/iomgr/pollset_set_windows.h
+++ b/src/core/lib/iomgr/pollset_set_windows.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/pollset_uv.c b/src/core/lib/iomgr/pollset_uv.c
index 5923da98e2..946f0c8c60 100644
--- a/src/core/lib/iomgr/pollset_uv.c
+++ b/src/core/lib/iomgr/pollset_uv.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -46,6 +31,13 @@
 #include "src/core/lib/iomgr/pollset.h"
 #include "src/core/lib/iomgr/pollset_uv.h"
 
+#include "src/core/lib/debug/trace.h"
+
+#ifndef NDEBUG
+grpc_tracer_flag grpc_trace_fd_refcount =
+    GRPC_TRACER_INITIALIZER(false, "fd_refcount");
+#endif
+
 struct grpc_pollset {
   uv_timer_t timer;
   int shutting_down;
@@ -103,7 +95,7 @@ void grpc_pollset_shutdown(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
     // kick the loop once
     uv_timer_start(dummy_uv_handle, dummy_timer_cb, 0, 0);
   }
-  grpc_closure_sched(exec_ctx, closure, GRPC_ERROR_NONE);
+  GRPC_CLOSURE_SCHED(exec_ctx, closure, GRPC_ERROR_NONE);
 }
 
 void grpc_pollset_destroy(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset) {
diff --git a/src/core/lib/iomgr/pollset_uv.h b/src/core/lib/iomgr/pollset_uv.h
index 0715eb4295..566c110ca6 100644
--- a/src/core/lib/iomgr/pollset_uv.h
+++ b/src/core/lib/iomgr/pollset_uv.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/pollset_windows.c b/src/core/lib/iomgr/pollset_windows.c
index b5f454cfa9..ea017a6054 100644
--- a/src/core/lib/iomgr/pollset_windows.c
+++ b/src/core/lib/iomgr/pollset_windows.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -45,6 +30,11 @@
 
 #define GRPC_POLLSET_KICK_BROADCAST ((grpc_pollset_worker *)1)
 
+#ifndef NDEBUG
+grpc_tracer_flag grpc_trace_fd_refcount =
+    GRPC_TRACER_INITIALIZER(false, "fd_refcount");
+#endif
+
 gpr_mu grpc_polling_mu;
 static grpc_pollset_worker *g_active_poller;
 static grpc_pollset_worker g_global_root_worker;
@@ -110,7 +100,7 @@ void grpc_pollset_shutdown(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
   pollset->shutting_down = 1;
   grpc_pollset_kick(pollset, GRPC_POLLSET_KICK_BROADCAST);
   if (!pollset->is_iocp_worker) {
-    grpc_closure_sched(exec_ctx, closure, GRPC_ERROR_NONE);
+    GRPC_CLOSURE_SCHED(exec_ctx, closure, GRPC_ERROR_NONE);
   } else {
     pollset->on_shutdown = closure;
   }
@@ -158,7 +148,7 @@ grpc_error *grpc_pollset_work(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
       }
 
       if (pollset->shutting_down && pollset->on_shutdown != NULL) {
-        grpc_closure_sched(exec_ctx, pollset->on_shutdown, GRPC_ERROR_NONE);
+        GRPC_CLOSURE_SCHED(exec_ctx, pollset->on_shutdown, GRPC_ERROR_NONE);
         pollset->on_shutdown = NULL;
       }
       goto done;
diff --git a/src/core/lib/iomgr/pollset_windows.h b/src/core/lib/iomgr/pollset_windows.h
index 2642013afc..71878c3d30 100644
--- a/src/core/lib/iomgr/pollset_windows.h
+++ b/src/core/lib/iomgr/pollset_windows.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/port.h b/src/core/lib/iomgr/port.h
index 2a553f4114..f5d15b4850 100644
--- a/src/core/lib/iomgr/port.h
+++ b/src/core/lib/iomgr/port.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/resolve_address.h b/src/core/lib/iomgr/resolve_address.h
index e03d16fa4e..fe1dd78576 100644
--- a/src/core/lib/iomgr/resolve_address.h
+++ b/src/core/lib/iomgr/resolve_address.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/resolve_address_posix.c b/src/core/lib/iomgr/resolve_address_posix.c
index d0ede0f2d5..35dedc23de 100644
--- a/src/core/lib/iomgr/resolve_address_posix.c
+++ b/src/core/lib/iomgr/resolve_address_posix.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -169,7 +154,7 @@ typedef struct {
 static void do_request_thread(grpc_exec_ctx *exec_ctx, void *rp,
                               grpc_error *error) {
   request *r = rp;
-  grpc_closure_sched(
+  GRPC_CLOSURE_SCHED(
       exec_ctx, r->on_done,
       grpc_blocking_resolve_address(r->name, r->default_port, r->addrs_out));
   gpr_free(r->name);
@@ -190,13 +175,13 @@ static void resolve_address_impl(grpc_exec_ctx *exec_ctx, const char *name,
                                  grpc_closure *on_done,
                                  grpc_resolved_addresses **addrs) {
   request *r = gpr_malloc(sizeof(request));
-  grpc_closure_init(&r->request_closure, do_request_thread, r,
+  GRPC_CLOSURE_INIT(&r->request_closure, do_request_thread, r,
                     grpc_executor_scheduler);
   r->name = gpr_strdup(name);
   r->default_port = gpr_strdup(default_port);
   r->on_done = on_done;
   r->addrs_out = addrs;
-  grpc_closure_sched(exec_ctx, &r->request_closure, GRPC_ERROR_NONE);
+  GRPC_CLOSURE_SCHED(exec_ctx, &r->request_closure, GRPC_ERROR_NONE);
 }
 
 void (*grpc_resolve_address)(
diff --git a/src/core/lib/iomgr/resolve_address_uv.c b/src/core/lib/iomgr/resolve_address_uv.c
index 6b468764fc..a98b8e62db 100644
--- a/src/core/lib/iomgr/resolve_address_uv.c
+++ b/src/core/lib/iomgr/resolve_address_uv.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -69,7 +54,7 @@ static int retry_named_port_failure(int status, request *r,
         int retry_status;
         uv_getaddrinfo_t *req = gpr_malloc(sizeof(uv_getaddrinfo_t));
         req->data = r;
-        r->port = svc[i][1];
+        r->port = gpr_strdup(svc[i][1]);
         retry_status = uv_getaddrinfo(uv_default_loop(), req, getaddrinfo_cb,
                                       r->host, r->port, r->hints);
         if (retry_status < 0 || getaddrinfo_cb == NULL) {
@@ -139,9 +124,11 @@ static void getaddrinfo_callback(uv_getaddrinfo_t *req, int status,
   /* Either no retry was attempted, or the retry failed. Either way, the
      original error probably has more interesting information */
   error = handle_addrinfo_result(status, res, r->addresses);
-  grpc_closure_sched(&exec_ctx, r->on_done, error);
+  GRPC_CLOSURE_SCHED(&exec_ctx, r->on_done, error);
   grpc_exec_ctx_finish(&exec_ctx);
   gpr_free(r->hints);
+  gpr_free(r->host);
+  gpr_free(r->port);
   gpr_free(r);
   uv_freeaddrinfo(res);
 }
@@ -240,7 +227,7 @@ static void resolve_address_impl(grpc_exec_ctx *exec_ctx, const char *name,
   int s;
   err = try_split_host_port(name, default_port, &host, &port);
   if (err != GRPC_ERROR_NONE) {
-    grpc_closure_sched(exec_ctx, on_done, err);
+    GRPC_CLOSURE_SCHED(exec_ctx, on_done, err);
     return;
   }
   r = gpr_malloc(sizeof(request));
@@ -267,7 +254,7 @@ static void resolve_address_impl(grpc_exec_ctx *exec_ctx, const char *name,
     err = GRPC_ERROR_CREATE_FROM_STATIC_STRING("getaddrinfo failed");
     err = grpc_error_set_str(err, GRPC_ERROR_STR_OS_ERROR,
                              grpc_slice_from_static_string(uv_strerror(s)));
-    grpc_closure_sched(exec_ctx, on_done, err);
+    GRPC_CLOSURE_SCHED(exec_ctx, on_done, err);
     gpr_free(r);
     gpr_free(req);
     gpr_free(hints);
diff --git a/src/core/lib/iomgr/resolve_address_windows.c b/src/core/lib/iomgr/resolve_address_windows.c
index 22eca1fd3b..45cfd7248d 100644
--- a/src/core/lib/iomgr/resolve_address_windows.c
+++ b/src/core/lib/iomgr/resolve_address_windows.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -154,7 +139,7 @@ static void do_request_thread(grpc_exec_ctx *exec_ctx, void *rp,
   } else {
     GRPC_ERROR_REF(error);
   }
-  grpc_closure_sched(exec_ctx, r->on_done, error);
+  GRPC_CLOSURE_SCHED(exec_ctx, r->on_done, error);
   gpr_free(r->name);
   gpr_free(r->default_port);
   gpr_free(r);
@@ -173,13 +158,13 @@ static void resolve_address_impl(grpc_exec_ctx *exec_ctx, const char *name,
                                  grpc_closure *on_done,
                                  grpc_resolved_addresses **addresses) {
   request *r = gpr_malloc(sizeof(request));
-  grpc_closure_init(&r->request_closure, do_request_thread, r,
+  GRPC_CLOSURE_INIT(&r->request_closure, do_request_thread, r,
                     grpc_executor_scheduler);
   r->name = gpr_strdup(name);
   r->default_port = gpr_strdup(default_port);
   r->on_done = on_done;
   r->addresses = addresses;
-  grpc_closure_sched(exec_ctx, &r->request_closure, GRPC_ERROR_NONE);
+  GRPC_CLOSURE_SCHED(exec_ctx, &r->request_closure, GRPC_ERROR_NONE);
 }
 
 void (*grpc_resolve_address)(
diff --git a/src/core/lib/iomgr/resource_quota.c b/src/core/lib/iomgr/resource_quota.c
index 6b2b85cce0..a31d9eef93 100644
--- a/src/core/lib/iomgr/resource_quota.c
+++ b/src/core/lib/iomgr/resource_quota.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -44,7 +29,8 @@
 
 #include "src/core/lib/iomgr/combiner.h"
 
-grpc_tracer_flag grpc_resource_quota_trace = GRPC_TRACER_INITIALIZER(false);
+grpc_tracer_flag grpc_resource_quota_trace =
+    GRPC_TRACER_INITIALIZER(false, "resource_quota");
 
 #define MEMORY_USAGE_ESTIMATION_MAX 65536
 
@@ -274,7 +260,7 @@ static void rq_step_sched(grpc_exec_ctx *exec_ctx,
   if (resource_quota->step_scheduled) return;
   resource_quota->step_scheduled = true;
   grpc_resource_quota_ref_internal(resource_quota);
-  grpc_closure_sched(exec_ctx, &resource_quota->rq_step_closure,
+  GRPC_CLOSURE_SCHED(exec_ctx, &resource_quota->rq_step_closure,
                      GRPC_ERROR_NONE);
 }
 
@@ -320,7 +306,7 @@ static bool rq_alloc(grpc_exec_ctx *exec_ctx,
     }
     if (resource_user->free_pool >= 0) {
       resource_user->allocating = false;
-      grpc_closure_list_sched(exec_ctx, &resource_user->on_allocated);
+      GRPC_CLOSURE_LIST_SCHED(exec_ctx, &resource_user->on_allocated);
       gpr_mu_unlock(&resource_user->mu);
     } else {
       rulist_add_head(resource_user, GRPC_RULIST_AWAITING_ALLOCATION);
@@ -378,7 +364,7 @@ static bool rq_reclaim(grpc_exec_ctx *exec_ctx,
   resource_quota->debug_only_last_reclaimer_resource_user = resource_user;
   resource_quota->debug_only_last_initiated_reclaimer = c;
   resource_user->reclaimers[destructive] = NULL;
-  grpc_closure_run(exec_ctx, c, GRPC_ERROR_NONE);
+  GRPC_CLOSURE_RUN(exec_ctx, c, GRPC_ERROR_NONE);
   return true;
 }
 
@@ -459,7 +445,7 @@ static bool ru_post_reclaimer(grpc_exec_ctx *exec_ctx,
   resource_user->new_reclaimers[destructive] = NULL;
   GPR_ASSERT(resource_user->reclaimers[destructive] == NULL);
   if (gpr_atm_acq_load(&resource_user->shutdown) > 0) {
-    grpc_closure_sched(exec_ctx, closure, GRPC_ERROR_CANCELLED);
+    GRPC_CLOSURE_SCHED(exec_ctx, closure, GRPC_ERROR_CANCELLED);
     return false;
   }
   resource_user->reclaimers[destructive] = closure;
@@ -500,9 +486,9 @@ static void ru_post_destructive_reclaimer(grpc_exec_ctx *exec_ctx, void *ru,
 
 static void ru_shutdown(grpc_exec_ctx *exec_ctx, void *ru, grpc_error *error) {
   grpc_resource_user *resource_user = ru;
-  grpc_closure_sched(exec_ctx, resource_user->reclaimers[0],
+  GRPC_CLOSURE_SCHED(exec_ctx, resource_user->reclaimers[0],
                      GRPC_ERROR_CANCELLED);
-  grpc_closure_sched(exec_ctx, resource_user->reclaimers[1],
+  GRPC_CLOSURE_SCHED(exec_ctx, resource_user->reclaimers[1],
                      GRPC_ERROR_CANCELLED);
   resource_user->reclaimers[0] = NULL;
   resource_user->reclaimers[1] = NULL;
@@ -516,9 +502,9 @@ static void ru_destroy(grpc_exec_ctx *exec_ctx, void *ru, grpc_error *error) {
   for (int i = 0; i < GRPC_RULIST_COUNT; i++) {
     rulist_remove(resource_user, (grpc_rulist)i);
   }
-  grpc_closure_sched(exec_ctx, resource_user->reclaimers[0],
+  GRPC_CLOSURE_SCHED(exec_ctx, resource_user->reclaimers[0],
                      GRPC_ERROR_CANCELLED);
-  grpc_closure_sched(exec_ctx, resource_user->reclaimers[1],
+  GRPC_CLOSURE_SCHED(exec_ctx, resource_user->reclaimers[1],
                      GRPC_ERROR_CANCELLED);
   if (resource_user->free_pool != 0) {
     resource_user->resource_quota->free_pool += resource_user->free_pool;
@@ -540,7 +526,7 @@ static void ru_allocated_slices(grpc_exec_ctx *exec_ctx, void *arg,
                                                  slice_allocator->length));
     }
   }
-  grpc_closure_run(exec_ctx, &slice_allocator->on_done, GRPC_ERROR_REF(error));
+  GRPC_CLOSURE_RUN(exec_ctx, &slice_allocator->on_done, GRPC_ERROR_REF(error));
 }
 
 /*******************************************************************************
@@ -581,7 +567,7 @@ static void rq_reclamation_done(grpc_exec_ctx *exec_ctx, void *rq,
 grpc_resource_quota *grpc_resource_quota_create(const char *name) {
   grpc_resource_quota *resource_quota = gpr_malloc(sizeof(*resource_quota));
   gpr_ref_init(&resource_quota->refs, 1);
-  resource_quota->combiner = grpc_combiner_create(NULL);
+  resource_quota->combiner = grpc_combiner_create();
   resource_quota->free_pool = INT64_MAX;
   resource_quota->size = INT64_MAX;
   gpr_atm_no_barrier_store(&resource_quota->last_size, GPR_ATM_MAX);
@@ -594,12 +580,11 @@ grpc_resource_quota *grpc_resource_quota_create(const char *name) {
     gpr_asprintf(&resource_quota->name, "anonymous_pool_%" PRIxPTR,
                  (intptr_t)resource_quota);
   }
-  grpc_closure_init(
-      &resource_quota->rq_step_closure, rq_step, resource_quota,
-      grpc_combiner_finally_scheduler(resource_quota->combiner, true));
-  grpc_closure_init(&resource_quota->rq_reclamation_done_closure,
+  GRPC_CLOSURE_INIT(&resource_quota->rq_step_closure, rq_step, resource_quota,
+                    grpc_combiner_finally_scheduler(resource_quota->combiner));
+  GRPC_CLOSURE_INIT(&resource_quota->rq_reclamation_done_closure,
                     rq_reclamation_done, resource_quota,
-                    grpc_combiner_scheduler(resource_quota->combiner, false));
+                    grpc_combiner_scheduler(resource_quota->combiner));
   for (int i = 0; i < GRPC_RULIST_COUNT; i++) {
     resource_quota->roots[i] = NULL;
   }
@@ -649,8 +634,8 @@ void grpc_resource_quota_resize(grpc_resource_quota *resource_quota,
   a->size = (int64_t)size;
   gpr_atm_no_barrier_store(&resource_quota->last_size,
                            (gpr_atm)GPR_MIN((size_t)GPR_ATM_MAX, size));
-  grpc_closure_init(&a->closure, rq_resize, a, grpc_schedule_on_exec_ctx);
-  grpc_closure_sched(&exec_ctx, &a->closure, GRPC_ERROR_NONE);
+  GRPC_CLOSURE_INIT(&a->closure, rq_resize, a, grpc_schedule_on_exec_ctx);
+  GRPC_CLOSURE_SCHED(&exec_ctx, &a->closure, GRPC_ERROR_NONE);
   grpc_exec_ctx_finish(&exec_ctx);
 }
 
@@ -702,20 +687,20 @@ grpc_resource_user *grpc_resource_user_create(
   grpc_resource_user *resource_user = gpr_malloc(sizeof(*resource_user));
   resource_user->resource_quota =
       grpc_resource_quota_ref_internal(resource_quota);
-  grpc_closure_init(&resource_user->allocate_closure, &ru_allocate,
+  GRPC_CLOSURE_INIT(&resource_user->allocate_closure, &ru_allocate,
                     resource_user,
-                    grpc_combiner_scheduler(resource_quota->combiner, false));
-  grpc_closure_init(&resource_user->add_to_free_pool_closure,
+                    grpc_combiner_scheduler(resource_quota->combiner));
+  GRPC_CLOSURE_INIT(&resource_user->add_to_free_pool_closure,
                     &ru_add_to_free_pool, resource_user,
-                    grpc_combiner_scheduler(resource_quota->combiner, false));
-  grpc_closure_init(&resource_user->post_reclaimer_closure[0],
+                    grpc_combiner_scheduler(resource_quota->combiner));
+  GRPC_CLOSURE_INIT(&resource_user->post_reclaimer_closure[0],
                     &ru_post_benign_reclaimer, resource_user,
-                    grpc_combiner_scheduler(resource_quota->combiner, false));
-  grpc_closure_init(&resource_user->post_reclaimer_closure[1],
+                    grpc_combiner_scheduler(resource_quota->combiner));
+  GRPC_CLOSURE_INIT(&resource_user->post_reclaimer_closure[1],
                     &ru_post_destructive_reclaimer, resource_user,
-                    grpc_combiner_scheduler(resource_quota->combiner, false));
-  grpc_closure_init(&resource_user->destroy_closure, &ru_destroy, resource_user,
-                    grpc_combiner_scheduler(resource_quota->combiner, false));
+                    grpc_combiner_scheduler(resource_quota->combiner));
+  GRPC_CLOSURE_INIT(&resource_user->destroy_closure, &ru_destroy, resource_user,
+                    grpc_combiner_scheduler(resource_quota->combiner));
   gpr_mu_init(&resource_user->mu);
   gpr_atm_rel_store(&resource_user->refs, 1);
   gpr_atm_rel_store(&resource_user->shutdown, 0);
@@ -755,7 +740,7 @@ static void ru_unref_by(grpc_exec_ctx *exec_ctx,
   gpr_atm old = gpr_atm_full_fetch_add(&resource_user->refs, -amount);
   GPR_ASSERT(old >= amount);
   if (old == amount) {
-    grpc_closure_sched(exec_ctx, &resource_user->destroy_closure,
+    GRPC_CLOSURE_SCHED(exec_ctx, &resource_user->destroy_closure,
                        GRPC_ERROR_NONE);
   }
 }
@@ -772,12 +757,12 @@ void grpc_resource_user_unref(grpc_exec_ctx *exec_ctx,
 void grpc_resource_user_shutdown(grpc_exec_ctx *exec_ctx,
                                  grpc_resource_user *resource_user) {
   if (gpr_atm_full_fetch_add(&resource_user->shutdown, 1) == 0) {
-    grpc_closure_sched(exec_ctx,
-                       grpc_closure_create(
-                           ru_shutdown, resource_user,
-                           grpc_combiner_scheduler(
-                               resource_user->resource_quota->combiner, false)),
-                       GRPC_ERROR_NONE);
+    GRPC_CLOSURE_SCHED(
+        exec_ctx,
+        GRPC_CLOSURE_CREATE(
+            ru_shutdown, resource_user,
+            grpc_combiner_scheduler(resource_user->resource_quota->combiner)),
+        GRPC_ERROR_NONE);
   }
 }
 
@@ -797,11 +782,11 @@ void grpc_resource_user_alloc(grpc_exec_ctx *exec_ctx,
                              GRPC_ERROR_NONE);
     if (!resource_user->allocating) {
       resource_user->allocating = true;
-      grpc_closure_sched(exec_ctx, &resource_user->allocate_closure,
+      GRPC_CLOSURE_SCHED(exec_ctx, &resource_user->allocate_closure,
                          GRPC_ERROR_NONE);
     }
   } else {
-    grpc_closure_sched(exec_ctx, optional_on_done, GRPC_ERROR_NONE);
+    GRPC_CLOSURE_SCHED(exec_ctx, optional_on_done, GRPC_ERROR_NONE);
   }
   gpr_mu_unlock(&resource_user->mu);
 }
@@ -820,7 +805,7 @@ void grpc_resource_user_free(grpc_exec_ctx *exec_ctx,
   if (is_bigger_than_zero && was_zero_or_negative &&
       !resource_user->added_to_free_pool) {
     resource_user->added_to_free_pool = true;
-    grpc_closure_sched(exec_ctx, &resource_user->add_to_free_pool_closure,
+    GRPC_CLOSURE_SCHED(exec_ctx, &resource_user->add_to_free_pool_closure,
                        GRPC_ERROR_NONE);
   }
   gpr_mu_unlock(&resource_user->mu);
@@ -833,7 +818,7 @@ void grpc_resource_user_post_reclaimer(grpc_exec_ctx *exec_ctx,
                                        grpc_closure *closure) {
   GPR_ASSERT(resource_user->new_reclaimers[destructive] == NULL);
   resource_user->new_reclaimers[destructive] = closure;
-  grpc_closure_sched(exec_ctx,
+  GRPC_CLOSURE_SCHED(exec_ctx,
                      &resource_user->post_reclaimer_closure[destructive],
                      GRPC_ERROR_NONE);
 }
@@ -844,7 +829,7 @@ void grpc_resource_user_finish_reclamation(grpc_exec_ctx *exec_ctx,
     gpr_log(GPR_DEBUG, "RQ %s %s: reclamation complete",
             resource_user->resource_quota->name, resource_user->name);
   }
-  grpc_closure_sched(
+  GRPC_CLOSURE_SCHED(
       exec_ctx, &resource_user->resource_quota->rq_reclamation_done_closure,
       GRPC_ERROR_NONE);
 }
@@ -852,9 +837,9 @@ void grpc_resource_user_finish_reclamation(grpc_exec_ctx *exec_ctx,
 void grpc_resource_user_slice_allocator_init(
     grpc_resource_user_slice_allocator *slice_allocator,
     grpc_resource_user *resource_user, grpc_iomgr_cb_func cb, void *p) {
-  grpc_closure_init(&slice_allocator->on_allocated, ru_allocated_slices,
+  GRPC_CLOSURE_INIT(&slice_allocator->on_allocated, ru_allocated_slices,
                     slice_allocator, grpc_schedule_on_exec_ctx);
-  grpc_closure_init(&slice_allocator->on_done, cb, p,
+  GRPC_CLOSURE_INIT(&slice_allocator->on_done, cb, p,
                     grpc_schedule_on_exec_ctx);
   slice_allocator->resource_user = resource_user;
 }
diff --git a/src/core/lib/iomgr/resource_quota.h b/src/core/lib/iomgr/resource_quota.h
index 51122dad01..d66f9ae774 100644
--- a/src/core/lib/iomgr/resource_quota.h
+++ b/src/core/lib/iomgr/resource_quota.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/sockaddr.h b/src/core/lib/iomgr/sockaddr.h
index 52b504390d..206d596ccd 100644
--- a/src/core/lib/iomgr/sockaddr.h
+++ b/src/core/lib/iomgr/sockaddr.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/sockaddr_posix.h b/src/core/lib/iomgr/sockaddr_posix.h
index b150de42f7..22d57ca6bb 100644
--- a/src/core/lib/iomgr/sockaddr_posix.h
+++ b/src/core/lib/iomgr/sockaddr_posix.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/sockaddr_utils.c b/src/core/lib/iomgr/sockaddr_utils.c
index a6a4cac3e2..99dc2f1c78 100644
--- a/src/core/lib/iomgr/sockaddr_utils.c
+++ b/src/core/lib/iomgr/sockaddr_utils.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/sockaddr_utils.h b/src/core/lib/iomgr/sockaddr_utils.h
index be3ea2038f..7692b969f2 100644
--- a/src/core/lib/iomgr/sockaddr_utils.h
+++ b/src/core/lib/iomgr/sockaddr_utils.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/sockaddr_windows.h b/src/core/lib/iomgr/sockaddr_windows.h
index 971db5b32b..cf0f6b914d 100644
--- a/src/core/lib/iomgr/sockaddr_windows.h
+++ b/src/core/lib/iomgr/sockaddr_windows.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/socket_factory_posix.c b/src/core/lib/iomgr/socket_factory_posix.c
index 1050a14c46..0f82dea570 100644
--- a/src/core/lib/iomgr/socket_factory_posix.c
+++ b/src/core/lib/iomgr/socket_factory_posix.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2017, Google Inc.
- * All rights reserved.
+ * Copyright 2017 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -35,6 +20,7 @@
 
 #ifdef GRPC_POSIX_SOCKET
 
+#include "src/core/lib/channel/channel_args.h"
 #include "src/core/lib/iomgr/socket_factory_posix.h"
 
 #include <grpc/impl/codegen/grpc_types.h>
@@ -99,12 +85,8 @@ static const grpc_arg_pointer_vtable socket_factory_arg_vtable = {
     socket_factory_arg_copy, socket_factory_arg_destroy, socket_factory_cmp};
 
 grpc_arg grpc_socket_factory_to_arg(grpc_socket_factory *factory) {
-  grpc_arg arg;
-  arg.type = GRPC_ARG_POINTER;
-  arg.key = GRPC_ARG_SOCKET_FACTORY;
-  arg.value.pointer.vtable = &socket_factory_arg_vtable;
-  arg.value.pointer.p = factory;
-  return arg;
+  return grpc_channel_arg_pointer_create(GRPC_ARG_SOCKET_FACTORY, factory,
+                                         &socket_factory_arg_vtable);
 }
 
 #endif
diff --git a/src/core/lib/iomgr/socket_factory_posix.h b/src/core/lib/iomgr/socket_factory_posix.h
index 2c63299030..a46938b06e 100644
--- a/src/core/lib/iomgr/socket_factory_posix.h
+++ b/src/core/lib/iomgr/socket_factory_posix.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2017, Google Inc.
- * All rights reserved.
+ * Copyright 2017 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/socket_mutator.c b/src/core/lib/iomgr/socket_mutator.c
index 34b61dcfe5..5d6c2c400e 100644
--- a/src/core/lib/iomgr/socket_mutator.c
+++ b/src/core/lib/iomgr/socket_mutator.c
@@ -1,38 +1,25 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
 #include "src/core/lib/iomgr/socket_mutator.h"
 
+#include "src/core/lib/channel/channel_args.h"
+
 #include <grpc/impl/codegen/grpc_types.h>
 #include <grpc/support/sync.h>
 #include <grpc/support/useful.h>
@@ -89,10 +76,6 @@ static const grpc_arg_pointer_vtable socket_mutator_arg_vtable = {
     socket_mutator_arg_copy, socket_mutator_arg_destroy, socket_mutator_cmp};
 
 grpc_arg grpc_socket_mutator_to_arg(grpc_socket_mutator *mutator) {
-  grpc_arg arg;
-  arg.type = GRPC_ARG_POINTER;
-  arg.key = GRPC_ARG_SOCKET_MUTATOR;
-  arg.value.pointer.vtable = &socket_mutator_arg_vtable;
-  arg.value.pointer.p = mutator;
-  return arg;
+  return grpc_channel_arg_pointer_create(GRPC_ARG_SOCKET_MUTATOR, mutator,
+                                         &socket_mutator_arg_vtable);
 }
diff --git a/src/core/lib/iomgr/socket_mutator.h b/src/core/lib/iomgr/socket_mutator.h
index 28b1710ec4..ba956e16f0 100644
--- a/src/core/lib/iomgr/socket_mutator.h
+++ b/src/core/lib/iomgr/socket_mutator.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/socket_utils.h b/src/core/lib/iomgr/socket_utils.h
index cc3ee2e30c..03fe46e5e9 100644
--- a/src/core/lib/iomgr/socket_utils.h
+++ b/src/core/lib/iomgr/socket_utils.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/socket_utils_common_posix.c b/src/core/lib/iomgr/socket_utils_common_posix.c
index bbe642d0fb..b8e2a0cdfd 100644
--- a/src/core/lib/iomgr/socket_utils_common_posix.c
+++ b/src/core/lib/iomgr/socket_utils_common_posix.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/socket_utils_linux.c b/src/core/lib/iomgr/socket_utils_linux.c
index bf6e9e4f55..e7b094d216 100644
--- a/src/core/lib/iomgr/socket_utils_linux.c
+++ b/src/core/lib/iomgr/socket_utils_linux.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/socket_utils_posix.c b/src/core/lib/iomgr/socket_utils_posix.c
index 9dea0c0cd8..dfd1ffd1e3 100644
--- a/src/core/lib/iomgr/socket_utils_posix.c
+++ b/src/core/lib/iomgr/socket_utils_posix.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/socket_utils_posix.h b/src/core/lib/iomgr/socket_utils_posix.h
index 2c2fc95ff9..eef80b439e 100644
--- a/src/core/lib/iomgr/socket_utils_posix.h
+++ b/src/core/lib/iomgr/socket_utils_posix.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/socket_utils_uv.c b/src/core/lib/iomgr/socket_utils_uv.c
index 741bf28969..0f7de4dfad 100644
--- a/src/core/lib/iomgr/socket_utils_uv.c
+++ b/src/core/lib/iomgr/socket_utils_uv.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/socket_utils_windows.c b/src/core/lib/iomgr/socket_utils_windows.c
index 5bbe8fa34c..2732c159aa 100644
--- a/src/core/lib/iomgr/socket_utils_windows.c
+++ b/src/core/lib/iomgr/socket_utils_windows.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/socket_windows.c b/src/core/lib/iomgr/socket_windows.c
index 2f2e02f715..a0d731b942 100644
--- a/src/core/lib/iomgr/socket_windows.c
+++ b/src/core/lib/iomgr/socket_windows.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -131,7 +116,7 @@ static void socket_notify_on_iocp(grpc_exec_ctx *exec_ctx,
   gpr_mu_lock(&socket->state_mu);
   if (info->has_pending_iocp) {
     info->has_pending_iocp = 0;
-    grpc_closure_sched(exec_ctx, closure, GRPC_ERROR_NONE);
+    GRPC_CLOSURE_SCHED(exec_ctx, closure, GRPC_ERROR_NONE);
   } else {
     info->closure = closure;
   }
@@ -154,7 +139,7 @@ void grpc_socket_become_ready(grpc_exec_ctx *exec_ctx, grpc_winsocket *socket,
   GPR_ASSERT(!info->has_pending_iocp);
   gpr_mu_lock(&socket->state_mu);
   if (info->closure) {
-    grpc_closure_sched(exec_ctx, info->closure, GRPC_ERROR_NONE);
+    GRPC_CLOSURE_SCHED(exec_ctx, info->closure, GRPC_ERROR_NONE);
     info->closure = NULL;
   } else {
     info->has_pending_iocp = 1;
diff --git a/src/core/lib/iomgr/socket_windows.h b/src/core/lib/iomgr/socket_windows.h
index a3875ce16c..67dc4ca53e 100644
--- a/src/core/lib/iomgr/socket_windows.h
+++ b/src/core/lib/iomgr/socket_windows.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/sys_epoll_wrapper.h b/src/core/lib/iomgr/sys_epoll_wrapper.h
index 2f08423193..3fa5357156 100644
--- a/src/core/lib/iomgr/sys_epoll_wrapper.h
+++ b/src/core/lib/iomgr/sys_epoll_wrapper.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2017, Google Inc.
- * All rights reserved.
+ * Copyright 2017 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/tcp_client.h b/src/core/lib/iomgr/tcp_client.h
index 6f05967fac..c04fb8bc07 100644
--- a/src/core/lib/iomgr/tcp_client.h
+++ b/src/core/lib/iomgr/tcp_client.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/tcp_client_posix.c b/src/core/lib/iomgr/tcp_client_posix.c
index 9ce7f8904d..992e1868c0 100644
--- a/src/core/lib/iomgr/tcp_client_posix.c
+++ b/src/core/lib/iomgr/tcp_client_posix.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -249,7 +234,7 @@ finish:
     grpc_channel_args_destroy(exec_ctx, ac->channel_args);
     gpr_free(ac);
   }
-  grpc_closure_sched(exec_ctx, closure, error);
+  GRPC_CLOSURE_SCHED(exec_ctx, closure, error);
 }
 
 static void tcp_client_connect_impl(grpc_exec_ctx *exec_ctx,
@@ -278,7 +263,7 @@ static void tcp_client_connect_impl(grpc_exec_ctx *exec_ctx,
 
   error = grpc_create_dualstack_socket(addr, SOCK_STREAM, 0, &dsmode, &fd);
   if (error != GRPC_ERROR_NONE) {
-    grpc_closure_sched(exec_ctx, closure, error);
+    GRPC_CLOSURE_SCHED(exec_ctx, closure, error);
     return;
   }
   if (dsmode == GRPC_DSMODE_IPV4) {
@@ -287,7 +272,7 @@ static void tcp_client_connect_impl(grpc_exec_ctx *exec_ctx,
     addr = &addr4_copy;
   }
   if ((error = prepare_socket(addr, fd, channel_args)) != GRPC_ERROR_NONE) {
-    grpc_closure_sched(exec_ctx, closure, error);
+    GRPC_CLOSURE_SCHED(exec_ctx, closure, error);
     return;
   }
 
@@ -305,13 +290,13 @@ static void tcp_client_connect_impl(grpc_exec_ctx *exec_ctx,
   if (err >= 0) {
     *ep =
         grpc_tcp_client_create_from_fd(exec_ctx, fdobj, channel_args, addr_str);
-    grpc_closure_sched(exec_ctx, closure, GRPC_ERROR_NONE);
+    GRPC_CLOSURE_SCHED(exec_ctx, closure, GRPC_ERROR_NONE);
     goto done;
   }
 
   if (errno != EWOULDBLOCK && errno != EINPROGRESS) {
     grpc_fd_orphan(exec_ctx, fdobj, NULL, NULL, "tcp_client_connect_error");
-    grpc_closure_sched(exec_ctx, closure, GRPC_OS_ERROR(errno, "connect"));
+    GRPC_CLOSURE_SCHED(exec_ctx, closure, GRPC_OS_ERROR(errno, "connect"));
     goto done;
   }
 
@@ -326,7 +311,7 @@ static void tcp_client_connect_impl(grpc_exec_ctx *exec_ctx,
   addr_str = NULL;
   gpr_mu_init(&ac->mu);
   ac->refs = 2;
-  grpc_closure_init(&ac->write_closure, on_writable, ac,
+  GRPC_CLOSURE_INIT(&ac->write_closure, on_writable, ac,
                     grpc_schedule_on_exec_ctx);
   ac->channel_args = grpc_channel_args_copy(channel_args);
 
@@ -336,7 +321,7 @@ static void tcp_client_connect_impl(grpc_exec_ctx *exec_ctx,
   }
 
   gpr_mu_lock(&ac->mu);
-  grpc_closure_init(&ac->on_alarm, tc_on_alarm, ac, grpc_schedule_on_exec_ctx);
+  GRPC_CLOSURE_INIT(&ac->on_alarm, tc_on_alarm, ac, grpc_schedule_on_exec_ctx);
   grpc_timer_init(exec_ctx, &ac->alarm, deadline, &ac->on_alarm);
   grpc_fd_notify_on_write(exec_ctx, ac->fd, &ac->write_closure);
   gpr_mu_unlock(&ac->mu);
diff --git a/src/core/lib/iomgr/tcp_client_posix.h b/src/core/lib/iomgr/tcp_client_posix.h
index efc5fcd5bb..b5a3814799 100644
--- a/src/core/lib/iomgr/tcp_client_posix.h
+++ b/src/core/lib/iomgr/tcp_client_posix.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/tcp_client_uv.c b/src/core/lib/iomgr/tcp_client_uv.c
index f0856a76d4..2f1d237c07 100644
--- a/src/core/lib/iomgr/tcp_client_uv.c
+++ b/src/core/lib/iomgr/tcp_client_uv.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -63,6 +48,7 @@ typedef struct grpc_uv_tcp_connect {
 static void uv_tcp_connect_cleanup(grpc_exec_ctx *exec_ctx,
                                    grpc_uv_tcp_connect *connect) {
   grpc_resource_quota_unref_internal(exec_ctx, connect->resource_quota);
+  gpr_free(connect->addr_name);
   gpr_free(connect);
 }
 
@@ -120,9 +106,10 @@ static void uv_tc_on_connect(uv_connect_t *req, int status) {
   }
   done = (--connect->refs == 0);
   if (done) {
+    grpc_exec_ctx_flush(&exec_ctx);
     uv_tcp_connect_cleanup(&exec_ctx, connect);
   }
-  grpc_closure_sched(&exec_ctx, closure, error);
+  GRPC_CLOSURE_SCHED(&exec_ctx, closure, error);
   grpc_exec_ctx_finish(&exec_ctx);
 }
 
@@ -155,6 +142,7 @@ static void tcp_client_connect_impl(grpc_exec_ctx *exec_ctx,
   connect->resource_quota = resource_quota;
   uv_tcp_init(uv_default_loop(), connect->tcp_handle);
   connect->connect_req.data = connect;
+  connect->refs = 1;
 
   if (GRPC_TRACER_ON(grpc_tcp_trace)) {
     gpr_log(GPR_DEBUG, "CLIENT_CONNECT: %s: asynchronously connecting",
@@ -165,7 +153,7 @@ static void tcp_client_connect_impl(grpc_exec_ctx *exec_ctx,
   uv_tcp_connect(&connect->connect_req, connect->tcp_handle,
                  (const struct sockaddr *)resolved_addr->addr,
                  uv_tc_on_connect);
-  grpc_closure_init(&connect->on_alarm, uv_tc_on_alarm, connect,
+  GRPC_CLOSURE_INIT(&connect->on_alarm, uv_tc_on_alarm, connect,
                     grpc_schedule_on_exec_ctx);
   grpc_timer_init(exec_ctx, &connect->alarm,
                   gpr_convert_clock_type(deadline, GPR_CLOCK_MONOTONIC),
diff --git a/src/core/lib/iomgr/tcp_client_windows.c b/src/core/lib/iomgr/tcp_client_windows.c
index d6baca50ba..fc62105cc9 100644
--- a/src/core/lib/iomgr/tcp_client_windows.c
+++ b/src/core/lib/iomgr/tcp_client_windows.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -131,7 +116,7 @@ static void on_connect(grpc_exec_ctx *exec_ctx, void *acp, grpc_error *error) {
   async_connect_unlock_and_cleanup(exec_ctx, ac, socket);
   /* If the connection was aborted, the callback was already called when
      the deadline was met. */
-  grpc_closure_sched(exec_ctx, on_done, error);
+  GRPC_CLOSURE_SCHED(exec_ctx, on_done, error);
 }
 
 /* Tries to issue one async connection, then schedules both an IOCP
@@ -216,9 +201,9 @@ static void tcp_client_connect_impl(
   ac->addr_name = grpc_sockaddr_to_uri(addr);
   ac->endpoint = endpoint;
   ac->channel_args = grpc_channel_args_copy(channel_args);
-  grpc_closure_init(&ac->on_connect, on_connect, ac, grpc_schedule_on_exec_ctx);
+  GRPC_CLOSURE_INIT(&ac->on_connect, on_connect, ac, grpc_schedule_on_exec_ctx);
 
-  grpc_closure_init(&ac->on_alarm, on_alarm, ac, grpc_schedule_on_exec_ctx);
+  GRPC_CLOSURE_INIT(&ac->on_alarm, on_alarm, ac, grpc_schedule_on_exec_ctx);
   grpc_timer_init(exec_ctx, &ac->alarm, deadline, &ac->on_alarm,
                   gpr_now(GPR_CLOCK_MONOTONIC));
   grpc_socket_notify_on_write(exec_ctx, socket, &ac->on_connect);
@@ -237,7 +222,7 @@ failure:
   } else if (sock != INVALID_SOCKET) {
     closesocket(sock);
   }
-  grpc_closure_sched(exec_ctx, on_done, final_error);
+  GRPC_CLOSURE_SCHED(exec_ctx, on_done, final_error);
 }
 
 // overridden by api_fuzzer.c
diff --git a/src/core/lib/iomgr/tcp_posix.c b/src/core/lib/iomgr/tcp_posix.c
index 5d360b0b80..b6dcd15cb0 100644
--- a/src/core/lib/iomgr/tcp_posix.c
+++ b/src/core/lib/iomgr/tcp_posix.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -74,7 +59,7 @@ typedef GRPC_MSG_IOVLEN_TYPE msg_iovlen_type;
 typedef size_t msg_iovlen_type;
 #endif
 
-grpc_tracer_flag grpc_tcp_trace = GRPC_TRACER_INITIALIZER(false);
+grpc_tracer_flag grpc_tcp_trace = GRPC_TRACER_INITIALIZER(false, "tcp");
 
 typedef struct {
   grpc_endpoint base;
@@ -178,15 +163,18 @@ static void tcp_free(grpc_exec_ctx *exec_ctx, grpc_tcp *tcp) {
   gpr_free(tcp);
 }
 
-/*#define GRPC_TCP_REFCOUNT_DEBUG*/
-#ifdef GRPC_TCP_REFCOUNT_DEBUG
+#ifndef NDEBUG
 #define TCP_UNREF(cl, tcp, reason) \
   tcp_unref((cl), (tcp), (reason), __FILE__, __LINE__)
 #define TCP_REF(tcp, reason) tcp_ref((tcp), (reason), __FILE__, __LINE__)
 static void tcp_unref(grpc_exec_ctx *exec_ctx, grpc_tcp *tcp,
                       const char *reason, const char *file, int line) {
-  gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG, "TCP unref %p : %s %d -> %d", tcp,
-          reason, tcp->refcount.count, tcp->refcount.count - 1);
+  if (GRPC_TRACER_ON(grpc_tcp_trace)) {
+    gpr_atm val = gpr_atm_no_barrier_load(&tcp->refcount.count);
+    gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
+            "TCP unref %p : %s %" PRIdPTR " -> %" PRIdPTR, tcp, reason, val,
+            val - 1);
+  }
   if (gpr_unref(&tcp->refcount)) {
     tcp_free(exec_ctx, tcp);
   }
@@ -194,8 +182,12 @@ static void tcp_unref(grpc_exec_ctx *exec_ctx, grpc_tcp *tcp,
 
 static void tcp_ref(grpc_tcp *tcp, const char *reason, const char *file,
                     int line) {
-  gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG, "TCP   ref %p : %s %d -> %d", tcp,
-          reason, tcp->refcount.count, tcp->refcount.count + 1);
+  if (GRPC_TRACER_ON(grpc_tcp_trace)) {
+    gpr_atm val = gpr_atm_no_barrier_load(&tcp->refcount.count);
+    gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
+            "TCP   ref %p : %s %" PRIdPTR " -> %" PRIdPTR, tcp, reason, val,
+            val + 1);
+  }
   gpr_ref(&tcp->refcount);
 }
 #else
@@ -236,7 +228,7 @@ static void call_read_cb(grpc_exec_ctx *exec_ctx, grpc_tcp *tcp,
 
   tcp->read_cb = NULL;
   tcp->incoming_buffer = NULL;
-  grpc_closure_run(exec_ctx, cb, error);
+  GRPC_CLOSURE_RUN(exec_ctx, cb, error);
 }
 
 #define MAX_READ_IOVEC 4
@@ -363,7 +355,7 @@ static void tcp_read(grpc_exec_ctx *exec_ctx, grpc_endpoint *ep,
     tcp->finished_edge = false;
     grpc_fd_notify_on_read(exec_ctx, tcp->em_fd, &tcp->read_closure);
   } else {
-    grpc_closure_sched(exec_ctx, &tcp->read_closure, GRPC_ERROR_NONE);
+    GRPC_CLOSURE_SCHED(exec_ctx, &tcp->read_closure, GRPC_ERROR_NONE);
   }
 }
 
@@ -480,7 +472,7 @@ static void tcp_handle_write(grpc_exec_ctx *exec_ctx, void *arg /* grpc_tcp */,
       gpr_log(GPR_DEBUG, "write: %s", str);
     }
 
-    grpc_closure_run(exec_ctx, cb, error);
+    GRPC_CLOSURE_RUN(exec_ctx, cb, error);
     TCP_UNREF(exec_ctx, tcp, "write");
   }
 }
@@ -506,7 +498,7 @@ static void tcp_write(grpc_exec_ctx *exec_ctx, grpc_endpoint *ep,
 
   if (buf->length == 0) {
     GPR_TIMER_END("tcp_write", 0);
-    grpc_closure_sched(
+    GRPC_CLOSURE_SCHED(
         exec_ctx, cb,
         grpc_fd_is_shutdown(tcp->em_fd)
             ? tcp_annotate_error(GRPC_ERROR_CREATE_FROM_STATIC_STRING("EOF"),
@@ -530,7 +522,7 @@ static void tcp_write(grpc_exec_ctx *exec_ctx, grpc_endpoint *ep,
       const char *str = grpc_error_string(error);
       gpr_log(GPR_DEBUG, "write: %s", str);
     }
-    grpc_closure_sched(exec_ctx, cb, error);
+    GRPC_CLOSURE_SCHED(exec_ctx, cb, error);
   }
 
   GPR_TIMER_END("tcp_write", 0);
@@ -558,26 +550,15 @@ static int tcp_get_fd(grpc_endpoint *ep) {
   return tcp->fd;
 }
 
-static grpc_workqueue *tcp_get_workqueue(grpc_endpoint *ep) {
-  grpc_tcp *tcp = (grpc_tcp *)ep;
-  return grpc_fd_get_workqueue(tcp->em_fd);
-}
-
 static grpc_resource_user *tcp_get_resource_user(grpc_endpoint *ep) {
   grpc_tcp *tcp = (grpc_tcp *)ep;
   return tcp->resource_user;
 }
 
-static const grpc_endpoint_vtable vtable = {tcp_read,
-                                            tcp_write,
-                                            tcp_get_workqueue,
-                                            tcp_add_to_pollset,
-                                            tcp_add_to_pollset_set,
-                                            tcp_shutdown,
-                                            tcp_destroy,
-                                            tcp_get_resource_user,
-                                            tcp_get_peer,
-                                            tcp_get_fd};
+static const grpc_endpoint_vtable vtable = {
+    tcp_read,     tcp_write,   tcp_add_to_pollset,    tcp_add_to_pollset_set,
+    tcp_shutdown, tcp_destroy, tcp_get_resource_user, tcp_get_peer,
+    tcp_get_fd};
 
 #define MAX_CHUNK_SIZE 32 * 1024 * 1024
 
@@ -642,9 +623,9 @@ grpc_endpoint *grpc_tcp_create(grpc_exec_ctx *exec_ctx, grpc_fd *em_fd,
   gpr_ref_init(&tcp->refcount, 1);
   gpr_atm_no_barrier_store(&tcp->shutdown_count, 0);
   tcp->em_fd = em_fd;
-  grpc_closure_init(&tcp->read_closure, tcp_handle_read, tcp,
+  GRPC_CLOSURE_INIT(&tcp->read_closure, tcp_handle_read, tcp,
                     grpc_schedule_on_exec_ctx);
-  grpc_closure_init(&tcp->write_closure, tcp_handle_write, tcp,
+  GRPC_CLOSURE_INIT(&tcp->write_closure, tcp_handle_write, tcp,
                     grpc_schedule_on_exec_ctx);
   grpc_slice_buffer_init(&tcp->last_read_buffer);
   tcp->resource_user = grpc_resource_user_create(resource_quota, peer_string);
diff --git a/src/core/lib/iomgr/tcp_posix.h b/src/core/lib/iomgr/tcp_posix.h
index 4ad60c116e..6831a4a57f 100644
--- a/src/core/lib/iomgr/tcp_posix.h
+++ b/src/core/lib/iomgr/tcp_posix.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/tcp_server.h b/src/core/lib/iomgr/tcp_server.h
index 437a94beff..8a126b6dee 100644
--- a/src/core/lib/iomgr/tcp_server.h
+++ b/src/core/lib/iomgr/tcp_server.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/tcp_server_posix.c b/src/core/lib/iomgr/tcp_server_posix.c
index 08997b5e2b..f304642951 100644
--- a/src/core/lib/iomgr/tcp_server_posix.c
+++ b/src/core/lib/iomgr/tcp_server_posix.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -136,7 +121,7 @@ static void finish_shutdown(grpc_exec_ctx *exec_ctx, grpc_tcp_server *s) {
   GPR_ASSERT(s->shutdown);
   gpr_mu_unlock(&s->mu);
   if (s->shutdown_complete != NULL) {
-    grpc_closure_sched(exec_ctx, s->shutdown_complete, GRPC_ERROR_NONE);
+    GRPC_CLOSURE_SCHED(exec_ctx, s->shutdown_complete, GRPC_ERROR_NONE);
   }
 
   gpr_mu_destroy(&s->mu);
@@ -178,7 +163,7 @@ static void deactivated_all_ports(grpc_exec_ctx *exec_ctx, grpc_tcp_server *s) {
     grpc_tcp_listener *sp;
     for (sp = s->head; sp; sp = sp->next) {
       grpc_unlink_if_unix_domain_socket(&sp->addr);
-      grpc_closure_init(&sp->destroyed_closure, destroyed_port, s,
+      GRPC_CLOSURE_INIT(&sp->destroyed_closure, destroyed_port, s,
                         grpc_schedule_on_exec_ctx);
       grpc_fd_orphan(exec_ctx, sp->emfd, &sp->destroyed_closure, NULL,
                      "tcp_listener_shutdown");
@@ -518,7 +503,7 @@ void grpc_tcp_server_start(grpc_exec_ctx *exec_ctx, grpc_tcp_server *s,
           "clone_port", clone_port(sp, (unsigned)(pollset_count - 1))));
       for (i = 0; i < pollset_count; i++) {
         grpc_pollset_add_fd(exec_ctx, pollsets[i], sp->emfd);
-        grpc_closure_init(&sp->read_closure, on_read, sp,
+        GRPC_CLOSURE_INIT(&sp->read_closure, on_read, sp,
                           grpc_schedule_on_exec_ctx);
         grpc_fd_notify_on_read(exec_ctx, sp->emfd, &sp->read_closure);
         s->active_ports++;
@@ -528,7 +513,7 @@ void grpc_tcp_server_start(grpc_exec_ctx *exec_ctx, grpc_tcp_server *s,
       for (i = 0; i < pollset_count; i++) {
         grpc_pollset_add_fd(exec_ctx, pollsets[i], sp->emfd);
       }
-      grpc_closure_init(&sp->read_closure, on_read, sp,
+      GRPC_CLOSURE_INIT(&sp->read_closure, on_read, sp,
                         grpc_schedule_on_exec_ctx);
       grpc_fd_notify_on_read(exec_ctx, sp->emfd, &sp->read_closure);
       s->active_ports++;
@@ -555,7 +540,7 @@ void grpc_tcp_server_unref(grpc_exec_ctx *exec_ctx, grpc_tcp_server *s) {
   if (gpr_unref(&s->refs)) {
     grpc_tcp_server_shutdown_listeners(exec_ctx, s);
     gpr_mu_lock(&s->mu);
-    grpc_closure_list_sched(exec_ctx, &s->shutdown_starting);
+    GRPC_CLOSURE_LIST_SCHED(exec_ctx, &s->shutdown_starting);
     gpr_mu_unlock(&s->mu);
     tcp_server_destroy(exec_ctx, s);
   }
diff --git a/src/core/lib/iomgr/tcp_server_utils_posix.h b/src/core/lib/iomgr/tcp_server_utils_posix.h
index c15e2e1493..85dea515d9 100644
--- a/src/core/lib/iomgr/tcp_server_utils_posix.h
+++ b/src/core/lib/iomgr/tcp_server_utils_posix.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2017, Google Inc.
- * All rights reserved.
+ * Copyright 2017 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/tcp_server_utils_posix_common.c b/src/core/lib/iomgr/tcp_server_utils_posix_common.c
index af2b00b4b5..dbb43186bd 100644
--- a/src/core/lib/iomgr/tcp_server_utils_posix_common.c
+++ b/src/core/lib/iomgr/tcp_server_utils_posix_common.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2017, Google Inc.
- * All rights reserved.
+ * Copyright 2017 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/tcp_server_utils_posix_ifaddrs.c b/src/core/lib/iomgr/tcp_server_utils_posix_ifaddrs.c
index 2078a68126..a243b69f35 100644
--- a/src/core/lib/iomgr/tcp_server_utils_posix_ifaddrs.c
+++ b/src/core/lib/iomgr/tcp_server_utils_posix_ifaddrs.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2017, Google Inc.
- * All rights reserved.
+ * Copyright 2017 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/tcp_server_utils_posix_noifaddrs.c b/src/core/lib/iomgr/tcp_server_utils_posix_noifaddrs.c
index d6a1a0693e..34eab20d6a 100644
--- a/src/core/lib/iomgr/tcp_server_utils_posix_noifaddrs.c
+++ b/src/core/lib/iomgr/tcp_server_utils_posix_noifaddrs.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2017, Google Inc.
- * All rights reserved.
+ * Copyright 2017 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/tcp_server_uv.c b/src/core/lib/iomgr/tcp_server_uv.c
index e9246948f5..2ab836cc34 100644
--- a/src/core/lib/iomgr/tcp_server_uv.c
+++ b/src/core/lib/iomgr/tcp_server_uv.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -56,6 +41,8 @@ struct grpc_tcp_listener {
   int port;
   /* linked list */
   struct grpc_tcp_listener *next;
+
+  bool closed;
 };
 
 struct grpc_tcp_server {
@@ -77,6 +64,8 @@ struct grpc_tcp_server {
   /* shutdown callback */
   grpc_closure *shutdown_complete;
 
+  bool shutdown;
+
   grpc_resource_quota *resource_quota;
 };
 
@@ -109,6 +98,7 @@ grpc_error *grpc_tcp_server_create(grpc_exec_ctx *exec_ctx,
   s->shutdown_starting.head = NULL;
   s->shutdown_starting.tail = NULL;
   s->shutdown_complete = shutdown_complete;
+  s->shutdown = false;
   *server = s;
   return GRPC_ERROR_NONE;
 }
@@ -125,8 +115,9 @@ void grpc_tcp_server_shutdown_starting_add(grpc_tcp_server *s,
 }
 
 static void finish_shutdown(grpc_exec_ctx *exec_ctx, grpc_tcp_server *s) {
+  GPR_ASSERT(s->shutdown);
   if (s->shutdown_complete != NULL) {
-    grpc_closure_sched(exec_ctx, s->shutdown_complete, GRPC_ERROR_NONE);
+    GRPC_CLOSURE_SCHED(exec_ctx, s->shutdown_complete, GRPC_ERROR_NONE);
   }
 
   while (s->head) {
@@ -144,21 +135,31 @@ static void handle_close_callback(uv_handle_t *handle) {
   grpc_tcp_listener *sp = (grpc_tcp_listener *)handle->data;
   grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
   sp->server->open_ports--;
-  if (sp->server->open_ports == 0) {
+  if (sp->server->open_ports == 0 && sp->server->shutdown) {
     finish_shutdown(&exec_ctx, sp->server);
   }
   grpc_exec_ctx_finish(&exec_ctx);
 }
 
+static void close_listener(grpc_tcp_listener *sp) {
+  if (!sp->closed) {
+    sp->closed = true;
+    uv_close((uv_handle_t *)sp->handle, handle_close_callback);
+  }
+}
+
 static void tcp_server_destroy(grpc_exec_ctx *exec_ctx, grpc_tcp_server *s) {
   int immediately_done = 0;
   grpc_tcp_listener *sp;
 
+  GPR_ASSERT(!s->shutdown);
+  s->shutdown = true;
+
   if (s->open_ports == 0) {
     immediately_done = 1;
   }
   for (sp = s->head; sp; sp = sp->next) {
-    uv_close((uv_handle_t *)sp->handle, handle_close_callback);
+    close_listener(sp);
   }
 
   if (immediately_done) {
@@ -170,7 +171,7 @@ void grpc_tcp_server_unref(grpc_exec_ctx *exec_ctx, grpc_tcp_server *s) {
   if (gpr_unref(&s->refs)) {
     /* Complete shutdown_starting work before destroying. */
     grpc_exec_ctx local_exec_ctx = GRPC_EXEC_CTX_INIT;
-    grpc_closure_list_sched(&local_exec_ctx, &s->shutdown_starting);
+    GRPC_CLOSURE_LIST_SCHED(&local_exec_ctx, &s->shutdown_starting);
     if (exec_ctx == NULL) {
       grpc_exec_ctx_flush(&local_exec_ctx);
       tcp_server_destroy(&local_exec_ctx, s);
@@ -196,9 +197,14 @@ static void on_connect(uv_stream_t *server, int status) {
   int err;
 
   if (status < 0) {
-    gpr_log(GPR_INFO, "Skipping on_accept due to error: %s",
-            uv_strerror(status));
-    return;
+    switch (status) {
+      case UV_EINTR:
+      case UV_EAGAIN:
+        return;
+      default:
+        close_listener(sp);
+        return;
+    }
   }
 
   client = gpr_malloc(sizeof(uv_tcp_t));
@@ -228,6 +234,7 @@ static void on_connect(uv_stream_t *server, int status) {
     sp->server->on_accept_cb(&exec_ctx, sp->server->on_accept_cb_arg, ep, NULL,
                              acceptor);
     grpc_exec_ctx_finish(&exec_ctx);
+    gpr_free(peer_name_string);
   }
 }
 
@@ -287,6 +294,7 @@ static grpc_error *add_socket_to_server(grpc_tcp_server *s, uv_tcp_t *handle,
   sp->handle = handle;
   sp->port = port;
   sp->port_index = port_index;
+  sp->closed = false;
   handle->data = sp;
   s->open_ports++;
   GPR_ASSERT(sp->handle);
diff --git a/src/core/lib/iomgr/tcp_server_windows.c b/src/core/lib/iomgr/tcp_server_windows.c
index 4c17f08918..0162afc1ad 100644
--- a/src/core/lib/iomgr/tcp_server_windows.c
+++ b/src/core/lib/iomgr/tcp_server_windows.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -149,10 +134,10 @@ static void destroy_server(grpc_exec_ctx *exec_ctx, void *arg,
 static void finish_shutdown_locked(grpc_exec_ctx *exec_ctx,
                                    grpc_tcp_server *s) {
   if (s->shutdown_complete != NULL) {
-    grpc_closure_sched(exec_ctx, s->shutdown_complete, GRPC_ERROR_NONE);
+    GRPC_CLOSURE_SCHED(exec_ctx, s->shutdown_complete, GRPC_ERROR_NONE);
   }
 
-  grpc_closure_sched(exec_ctx, grpc_closure_create(destroy_server, s,
+  GRPC_CLOSURE_SCHED(exec_ctx, GRPC_CLOSURE_CREATE(destroy_server, s,
                                                    grpc_schedule_on_exec_ctx),
                      GRPC_ERROR_NONE);
 }
@@ -191,7 +176,7 @@ void grpc_tcp_server_unref(grpc_exec_ctx *exec_ctx, grpc_tcp_server *s) {
   if (gpr_unref(&s->refs)) {
     grpc_tcp_server_shutdown_listeners(exec_ctx, s);
     gpr_mu_lock(&s->mu);
-    grpc_closure_list_sched(exec_ctx, &s->shutdown_starting);
+    GRPC_CLOSURE_LIST_SCHED(exec_ctx, &s->shutdown_starting);
     gpr_mu_unlock(&s->mu);
     tcp_server_destroy(exec_ctx, s);
   }
@@ -452,7 +437,7 @@ static grpc_error *add_socket_to_server(grpc_tcp_server *s, SOCKET sock,
   sp->new_socket = INVALID_SOCKET;
   sp->port = port;
   sp->port_index = port_index;
-  grpc_closure_init(&sp->on_accept, on_accept, sp, grpc_schedule_on_exec_ctx);
+  GRPC_CLOSURE_INIT(&sp->on_accept, on_accept, sp, grpc_schedule_on_exec_ctx);
   GPR_ASSERT(sp->socket);
   gpr_mu_unlock(&s->mu);
   *listener = sp;
diff --git a/src/core/lib/iomgr/tcp_uv.c b/src/core/lib/iomgr/tcp_uv.c
index e7157537f6..7c6a9b85f5 100644
--- a/src/core/lib/iomgr/tcp_uv.c
+++ b/src/core/lib/iomgr/tcp_uv.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -52,7 +37,7 @@
 #include "src/core/lib/slice/slice_string_helpers.h"
 #include "src/core/lib/support/string.h"
 
-grpc_tracer_flag grpc_tcp_trace = GRPC_TRACER_INITIALIZER(false);
+grpc_tracer_flag grpc_tcp_trace = GRPC_TRACER_INITIALIZER(false, "tcp");
 
 typedef struct {
   grpc_endpoint base;
@@ -80,20 +65,25 @@ typedef struct {
 } grpc_tcp;
 
 static void tcp_free(grpc_exec_ctx *exec_ctx, grpc_tcp *tcp) {
+  grpc_slice_unref_internal(exec_ctx, tcp->read_slice);
   grpc_resource_user_unref(exec_ctx, tcp->resource_user);
+  gpr_free(tcp->handle);
+  gpr_free(tcp->peer_string);
   gpr_free(tcp);
 }
 
-/*#define GRPC_TCP_REFCOUNT_DEBUG*/
-#ifdef GRPC_TCP_REFCOUNT_DEBUG
+#ifndef NDEBUG
 #define TCP_UNREF(exec_ctx, tcp, reason) \
   tcp_unref((exec_ctx), (tcp), (reason), __FILE__, __LINE__)
-#define TCP_REF(tcp, reason) \
-  tcp_ref((exec_ctx), (tcp), (reason), __FILE__, __LINE__)
+#define TCP_REF(tcp, reason) tcp_ref((tcp), (reason), __FILE__, __LINE__)
 static void tcp_unref(grpc_exec_ctx *exec_ctx, grpc_tcp *tcp,
                       const char *reason, const char *file, int line) {
-  gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG, "TCP unref %p : %s %d -> %d", tcp,
-          reason, tcp->refcount.count, tcp->refcount.count - 1);
+  if (GRPC_TRACER_ON(grpc_tcp_trace)) {
+    gpr_atm val = gpr_atm_no_barrier_load(&tcp->refcount.count);
+    gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
+            "TCP unref %p : %s %" PRIdPTR " -> %" PRIdPTR, tcp, reason, val,
+            val - 1);
+  }
   if (gpr_unref(&tcp->refcount)) {
     tcp_free(exec_ctx, tcp);
   }
@@ -101,8 +91,12 @@ static void tcp_unref(grpc_exec_ctx *exec_ctx, grpc_tcp *tcp,
 
 static void tcp_ref(grpc_tcp *tcp, const char *reason, const char *file,
                     int line) {
-  gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG, "TCP   ref %p : %s %d -> %d", tcp,
-          reason, tcp->refcount.count, tcp->refcount.count + 1);
+  if (GRPC_TRACER_ON(grpc_tcp_trace)) {
+    gpr_atm val = gpr_atm_no_barrier_load(&tcp->refcount.count);
+    gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
+            "TCP   ref %p : %s %" PRIdPTR " -> %" PRIdPTR, tcp, reason, val,
+            val + 1);
+  }
   gpr_ref(&tcp->refcount);
 }
 #else
@@ -124,13 +118,17 @@ static void uv_close_callback(uv_handle_t *handle) {
   grpc_exec_ctx_finish(&exec_ctx);
 }
 
+static grpc_slice alloc_read_slice(grpc_exec_ctx *exec_ctx,
+                                   grpc_resource_user *resource_user) {
+  return grpc_resource_user_slice_malloc(exec_ctx, resource_user,
+                                         GRPC_TCP_DEFAULT_READ_SLICE_SIZE);
+}
+
 static void alloc_uv_buf(uv_handle_t *handle, size_t suggested_size,
                          uv_buf_t *buf) {
   grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
   grpc_tcp *tcp = handle->data;
   (void)suggested_size;
-  tcp->read_slice = grpc_resource_user_slice_malloc(
-      &exec_ctx, tcp->resource_user, GRPC_TCP_DEFAULT_READ_SLICE_SIZE);
   buf->base = (char *)GRPC_SLICE_START_PTR(tcp->read_slice);
   buf->len = GRPC_SLICE_LENGTH(tcp->read_slice);
   grpc_exec_ctx_finish(&exec_ctx);
@@ -157,6 +155,7 @@ static void read_callback(uv_stream_t *stream, ssize_t nread,
     // Successful read
     sub = grpc_slice_sub_no_ref(tcp->read_slice, 0, (size_t)nread);
     grpc_slice_buffer_add(tcp->read_slices, sub);
+    tcp->read_slice = alloc_read_slice(&exec_ctx, tcp->resource_user);
     error = GRPC_ERROR_NONE;
     if (GRPC_TRACER_ON(grpc_tcp_trace)) {
       size_t i;
@@ -175,7 +174,7 @@ static void read_callback(uv_stream_t *stream, ssize_t nread,
     // nread < 0: Error
     error = GRPC_ERROR_CREATE_FROM_STATIC_STRING("TCP Read failed");
   }
-  grpc_closure_sched(&exec_ctx, cb, error);
+  GRPC_CLOSURE_SCHED(&exec_ctx, cb, error);
   grpc_exec_ctx_finish(&exec_ctx);
 }
 
@@ -197,7 +196,7 @@ static void uv_endpoint_read(grpc_exec_ctx *exec_ctx, grpc_endpoint *ep,
     error =
         grpc_error_set_str(error, GRPC_ERROR_STR_OS_ERROR,
                            grpc_slice_from_static_string(uv_strerror(status)));
-    grpc_closure_sched(exec_ctx, cb, error);
+    GRPC_CLOSURE_SCHED(exec_ctx, cb, error);
   }
   if (GRPC_TRACER_ON(grpc_tcp_trace)) {
     const char *str = grpc_error_string(error);
@@ -224,7 +223,7 @@ static void write_callback(uv_write_t *req, int status) {
   gpr_free(tcp->write_buffers);
   grpc_resource_user_free(&exec_ctx, tcp->resource_user,
                           sizeof(uv_buf_t) * tcp->write_slices->count);
-  grpc_closure_sched(&exec_ctx, cb, error);
+  GRPC_CLOSURE_SCHED(&exec_ctx, cb, error);
   grpc_exec_ctx_finish(&exec_ctx);
 }
 
@@ -250,7 +249,7 @@ static void uv_endpoint_write(grpc_exec_ctx *exec_ctx, grpc_endpoint *ep,
   }
 
   if (tcp->shutting_down) {
-    grpc_closure_sched(exec_ctx, cb, GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+    GRPC_CLOSURE_SCHED(exec_ctx, cb, GRPC_ERROR_CREATE_FROM_STATIC_STRING(
                                          "TCP socket is shutting down"));
     return;
   }
@@ -261,7 +260,7 @@ static void uv_endpoint_write(grpc_exec_ctx *exec_ctx, grpc_endpoint *ep,
   if (tcp->write_slices->count == 0) {
     // No slices means we don't have to do anything,
     // and libuv doesn't like empty writes
-    grpc_closure_sched(exec_ctx, cb, GRPC_ERROR_NONE);
+    GRPC_CLOSURE_SCHED(exec_ctx, cb, GRPC_ERROR_NONE);
     return;
   }
 
@@ -311,6 +310,7 @@ static void uv_endpoint_shutdown(grpc_exec_ctx *exec_ctx, grpc_endpoint *ep,
     tcp->shutting_down = true;
     uv_shutdown_t *req = &tcp->shutdown_req;
     uv_shutdown(req, (uv_stream_t *)tcp->handle, shutdown_callback);
+    grpc_resource_user_shutdown(exec_ctx, tcp->resource_user);
   }
   GRPC_ERROR_UNREF(why);
 }
@@ -331,20 +331,18 @@ static grpc_resource_user *uv_get_resource_user(grpc_endpoint *ep) {
   return tcp->resource_user;
 }
 
-static grpc_workqueue *uv_get_workqueue(grpc_endpoint *ep) { return NULL; }
-
 static int uv_get_fd(grpc_endpoint *ep) { return -1; }
 
 static grpc_endpoint_vtable vtable = {
-    uv_endpoint_read,  uv_endpoint_write,     uv_get_workqueue,
-    uv_add_to_pollset, uv_add_to_pollset_set, uv_endpoint_shutdown,
-    uv_destroy,        uv_get_resource_user,  uv_get_peer,
-    uv_get_fd};
+    uv_endpoint_read,      uv_endpoint_write,    uv_add_to_pollset,
+    uv_add_to_pollset_set, uv_endpoint_shutdown, uv_destroy,
+    uv_get_resource_user,  uv_get_peer,          uv_get_fd};
 
 grpc_endpoint *grpc_tcp_create(uv_tcp_t *handle,
                                grpc_resource_quota *resource_quota,
                                char *peer_string) {
   grpc_tcp *tcp = (grpc_tcp *)gpr_malloc(sizeof(grpc_tcp));
+  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
 
   if (GRPC_TRACER_ON(grpc_tcp_trace)) {
     gpr_log(GPR_DEBUG, "Creating TCP endpoint %p", tcp);
@@ -361,6 +359,7 @@ grpc_endpoint *grpc_tcp_create(uv_tcp_t *handle,
   tcp->peer_string = gpr_strdup(peer_string);
   tcp->shutting_down = false;
   tcp->resource_user = grpc_resource_user_create(resource_quota, peer_string);
+  tcp->read_slice = alloc_read_slice(&exec_ctx, tcp->resource_user);
   /* Tell network status tracking code about the new endpoint */
   grpc_network_status_register_endpoint(&tcp->base);
 
@@ -368,6 +367,7 @@ grpc_endpoint *grpc_tcp_create(uv_tcp_t *handle,
   uv_unref((uv_handle_t *)handle);
 #endif
 
+  grpc_exec_ctx_finish(&exec_ctx);
   return &tcp->base;
 }
 
diff --git a/src/core/lib/iomgr/tcp_uv.h b/src/core/lib/iomgr/tcp_uv.h
index 106bec5eca..0e67481d35 100644
--- a/src/core/lib/iomgr/tcp_uv.h
+++ b/src/core/lib/iomgr/tcp_uv.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/tcp_windows.c b/src/core/lib/iomgr/tcp_windows.c
index bdd4dd07af..2cbb97403b 100644
--- a/src/core/lib/iomgr/tcp_windows.c
+++ b/src/core/lib/iomgr/tcp_windows.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -63,6 +48,8 @@
 #define GRPC_FIONBIO FIONBIO
 #endif
 
+grpc_tracer_flag grpc_tcp_trace = GRPC_TRACER_INITIALIZER(false, "tcp");
+
 static grpc_error *set_non_block(SOCKET sock) {
   int status;
   uint32_t param = 1;
@@ -130,15 +117,18 @@ static void tcp_free(grpc_exec_ctx *exec_ctx, grpc_tcp *tcp) {
   gpr_free(tcp);
 }
 
-/*#define GRPC_TCP_REFCOUNT_DEBUG*/
-#ifdef GRPC_TCP_REFCOUNT_DEBUG
+#ifndef NDEBUG
 #define TCP_UNREF(exec_ctx, tcp, reason) \
   tcp_unref((exec_ctx), (tcp), (reason), __FILE__, __LINE__)
 #define TCP_REF(tcp, reason) tcp_ref((tcp), (reason), __FILE__, __LINE__)
 static void tcp_unref(grpc_exec_ctx *exec_ctx, grpc_tcp *tcp,
                       const char *reason, const char *file, int line) {
-  gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG, "TCP unref %p : %s %d -> %d", tcp,
-          reason, tcp->refcount.count, tcp->refcount.count - 1);
+  if (GRPC_TRACER_ON(grpc_tcp_trace)) {
+    gpr_atm val = gpr_atm_no_barrier_load(&tcp->refcount.count);
+    gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
+            "TCP unref %p : %s %" PRIdPTR " -> %" PRIdPTR, tcp, reason, val,
+            val - 1);
+  }
   if (gpr_unref(&tcp->refcount)) {
     tcp_free(exec_ctx, tcp);
   }
@@ -146,8 +136,12 @@ static void tcp_unref(grpc_exec_ctx *exec_ctx, grpc_tcp *tcp,
 
 static void tcp_ref(grpc_tcp *tcp, const char *reason, const char *file,
                     int line) {
-  gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG, "TCP   ref %p : %s %d -> %d", tcp,
-          reason, tcp->refcount.count, tcp->refcount.count + 1);
+  if (GRPC_TRACER_ON(grpc_tcp_trace)) {
+    gpr_atm val = gpr_atm_no_barrier_load(&tcp->refcount.count);
+    gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
+            "TCP   ref %p : %s %" PRIdPTR " -> %" PRIdPTR, tcp, reason, val,
+            val + 1);
+  }
   gpr_ref(&tcp->refcount);
 }
 #else
@@ -194,7 +188,7 @@ static void on_read(grpc_exec_ctx *exec_ctx, void *tcpp, grpc_error *error) {
 
   tcp->read_cb = NULL;
   TCP_UNREF(exec_ctx, tcp, "read");
-  grpc_closure_sched(exec_ctx, cb, error);
+  GRPC_CLOSURE_SCHED(exec_ctx, cb, error);
 }
 
 static void win_read(grpc_exec_ctx *exec_ctx, grpc_endpoint *ep,
@@ -208,7 +202,7 @@ static void win_read(grpc_exec_ctx *exec_ctx, grpc_endpoint *ep,
   WSABUF buffer;
 
   if (tcp->shutting_down) {
-    grpc_closure_sched(
+    GRPC_CLOSURE_SCHED(
         exec_ctx, cb,
         GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
             "TCP socket is shutting down", &tcp->shutdown_error, 1));
@@ -235,7 +229,7 @@ static void win_read(grpc_exec_ctx *exec_ctx, grpc_endpoint *ep,
   /* Did we get data immediately ? Yay. */
   if (info->wsa_error != WSAEWOULDBLOCK) {
     info->bytes_transfered = bytes_read;
-    grpc_closure_sched(exec_ctx, &tcp->on_read, GRPC_ERROR_NONE);
+    GRPC_CLOSURE_SCHED(exec_ctx, &tcp->on_read, GRPC_ERROR_NONE);
     return;
   }
 
@@ -248,7 +242,7 @@ static void win_read(grpc_exec_ctx *exec_ctx, grpc_endpoint *ep,
     int wsa_error = WSAGetLastError();
     if (wsa_error != WSA_IO_PENDING) {
       info->wsa_error = wsa_error;
-      grpc_closure_sched(exec_ctx, &tcp->on_read,
+      GRPC_CLOSURE_SCHED(exec_ctx, &tcp->on_read,
                          GRPC_WSA_ERROR(info->wsa_error, "WSARecv"));
       return;
     }
@@ -280,7 +274,7 @@ static void on_write(grpc_exec_ctx *exec_ctx, void *tcpp, grpc_error *error) {
   }
 
   TCP_UNREF(exec_ctx, tcp, "write");
-  grpc_closure_sched(exec_ctx, cb, error);
+  GRPC_CLOSURE_SCHED(exec_ctx, cb, error);
 }
 
 /* Initiates a write. */
@@ -298,7 +292,7 @@ static void win_write(grpc_exec_ctx *exec_ctx, grpc_endpoint *ep,
   size_t len;
 
   if (tcp->shutting_down) {
-    grpc_closure_sched(
+    GRPC_CLOSURE_SCHED(
         exec_ctx, cb,
         GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
             "TCP socket is shutting down", &tcp->shutdown_error, 1));
@@ -332,7 +326,7 @@ static void win_write(grpc_exec_ctx *exec_ctx, grpc_endpoint *ep,
     grpc_error *error = status == 0
                             ? GRPC_ERROR_NONE
                             : GRPC_WSA_ERROR(info->wsa_error, "WSASend");
-    grpc_closure_sched(exec_ctx, cb, error);
+    GRPC_CLOSURE_SCHED(exec_ctx, cb, error);
     if (allocated) gpr_free(allocated);
     return;
   }
@@ -350,7 +344,7 @@ static void win_write(grpc_exec_ctx *exec_ctx, grpc_endpoint *ep,
     int wsa_error = WSAGetLastError();
     if (wsa_error != WSA_IO_PENDING) {
       TCP_UNREF(exec_ctx, tcp, "write");
-      grpc_closure_sched(exec_ctx, cb, GRPC_WSA_ERROR(wsa_error, "WSASend"));
+      GRPC_CLOSURE_SCHED(exec_ctx, cb, GRPC_WSA_ERROR(wsa_error, "WSASend"));
       return;
     }
   }
@@ -410,8 +404,6 @@ static char *win_get_peer(grpc_endpoint *ep) {
   return gpr_strdup(tcp->peer_string);
 }
 
-static grpc_workqueue *win_get_workqueue(grpc_endpoint *ep) { return NULL; }
-
 static grpc_resource_user *win_get_resource_user(grpc_endpoint *ep) {
   grpc_tcp *tcp = (grpc_tcp *)ep;
   return tcp->resource_user;
@@ -419,16 +411,10 @@ static grpc_resource_user *win_get_resource_user(grpc_endpoint *ep) {
 
 static int win_get_fd(grpc_endpoint *ep) { return -1; }
 
-static grpc_endpoint_vtable vtable = {win_read,
-                                      win_write,
-                                      win_get_workqueue,
-                                      win_add_to_pollset,
-                                      win_add_to_pollset_set,
-                                      win_shutdown,
-                                      win_destroy,
-                                      win_get_resource_user,
-                                      win_get_peer,
-                                      win_get_fd};
+static grpc_endpoint_vtable vtable = {
+    win_read,     win_write,   win_add_to_pollset,    win_add_to_pollset_set,
+    win_shutdown, win_destroy, win_get_resource_user, win_get_peer,
+    win_get_fd};
 
 grpc_endpoint *grpc_tcp_create(grpc_exec_ctx *exec_ctx, grpc_winsocket *socket,
                                grpc_channel_args *channel_args,
@@ -449,8 +435,8 @@ grpc_endpoint *grpc_tcp_create(grpc_exec_ctx *exec_ctx, grpc_winsocket *socket,
   tcp->socket = socket;
   gpr_mu_init(&tcp->mu);
   gpr_ref_init(&tcp->refcount, 1);
-  grpc_closure_init(&tcp->on_read, on_read, tcp, grpc_schedule_on_exec_ctx);
-  grpc_closure_init(&tcp->on_write, on_write, tcp, grpc_schedule_on_exec_ctx);
+  GRPC_CLOSURE_INIT(&tcp->on_read, on_read, tcp, grpc_schedule_on_exec_ctx);
+  GRPC_CLOSURE_INIT(&tcp->on_write, on_write, tcp, grpc_schedule_on_exec_ctx);
   tcp->peer_string = gpr_strdup(peer_string);
   tcp->resource_user = grpc_resource_user_create(resource_quota, peer_string);
   /* Tell network status tracking code about the new endpoint */
diff --git a/src/core/lib/iomgr/tcp_windows.h b/src/core/lib/iomgr/tcp_windows.h
index abafdb22d2..864184ce84 100644
--- a/src/core/lib/iomgr/tcp_windows.h
+++ b/src/core/lib/iomgr/tcp_windows.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/time_averaged_stats.c b/src/core/lib/iomgr/time_averaged_stats.c
index da9cae6f28..3bddec04dd 100644
--- a/src/core/lib/iomgr/time_averaged_stats.c
+++ b/src/core/lib/iomgr/time_averaged_stats.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/time_averaged_stats.h b/src/core/lib/iomgr/time_averaged_stats.h
index 284b31f94a..8745f7fa13 100644
--- a/src/core/lib/iomgr/time_averaged_stats.h
+++ b/src/core/lib/iomgr/time_averaged_stats.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/timer.h b/src/core/lib/iomgr/timer.h
index 8ce785629d..89c997bdca 100644
--- a/src/core/lib/iomgr/timer.h
+++ b/src/core/lib/iomgr/timer.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -88,6 +73,12 @@ void grpc_timer_cancel(grpc_exec_ctx *exec_ctx, grpc_timer *timer);
 
 /* iomgr internal api for dealing with timers */
 
+typedef enum {
+  GRPC_TIMERS_NOT_CHECKED,
+  GRPC_TIMERS_CHECKED_AND_EMPTY,
+  GRPC_TIMERS_FIRED,
+} grpc_timer_check_result;
+
 /* Check for timers to be run, and run them.
    Return true if timer callbacks were executed.
    If next is non-null, TRY to update *next with the next running timer
@@ -95,7 +86,8 @@ void grpc_timer_cancel(grpc_exec_ctx *exec_ctx, grpc_timer *timer);
    *next is never guaranteed to be updated on any given execution; however,
    with high probability at least one thread in the system will see an update
    at any time slice. */
-bool grpc_timer_check(grpc_exec_ctx *exec_ctx, grpc_millis *next);
+grpc_timer_check_result grpc_timer_check(grpc_exec_ctx *exec_ctx,
+                                         grpc_millis *next);
 void grpc_timer_list_init(grpc_exec_ctx *exec_ctx);
 void grpc_timer_list_shutdown(grpc_exec_ctx *exec_ctx);
 
diff --git a/src/core/lib/iomgr/timer_generic.c b/src/core/lib/iomgr/timer_generic.c
index bca05bd07d..11d0b338f1 100644
--- a/src/core/lib/iomgr/timer_generic.c
+++ b/src/core/lib/iomgr/timer_generic.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -56,41 +41,63 @@
 #define MIN_QUEUE_WINDOW_DURATION 0.01
 #define MAX_QUEUE_WINDOW_DURATION 1
 
-grpc_tracer_flag grpc_timer_trace = GRPC_TRACER_INITIALIZER(false);
-grpc_tracer_flag grpc_timer_check_trace = GRPC_TRACER_INITIALIZER(false);
+grpc_tracer_flag grpc_timer_trace = GRPC_TRACER_INITIALIZER(false, "timer");
+grpc_tracer_flag grpc_timer_check_trace =
+    GRPC_TRACER_INITIALIZER(false, "timer_check");
 
+/* A "timer shard". Contains a 'heap' and a 'list' of timers. All timers with
+ * deadlines earlier than 'queue_deadline" cap are maintained in the heap and
+ * others are maintained in the list (unordered). This helps to keep the number
+ * of elements in the heap low.
+ *
+ * The 'queue_deadline_cap' gets recomputed periodically based on the timer
+ * stats maintained in 'stats' and the relevant timers are then moved from the
+ * 'list' to 'heap'
+ */
 typedef struct {
   gpr_mu mu;
   grpc_time_averaged_stats stats;
   /* All and only timers with deadlines <= this will be in the heap. */
   gpr_atm queue_deadline_cap;
+  /* The deadline of the next timer due in this shard */
   gpr_atm min_deadline;
-  /* Index in the g_shard_queue */
+  /* Index of this timer_shard in the g_shard_queue */
   uint32_t shard_queue_index;
   /* This holds all timers with deadlines < queue_deadline_cap. Timers in this
      list have the top bit of their deadline set to 0. */
   grpc_timer_heap heap;
   /* This holds timers whose deadline is >= queue_deadline_cap. */
   grpc_timer list;
-} shard_type;
+} timer_shard;
+
+/* Array of timer shards. Whenever a timer (grpc_timer *) is added, its address
+ * is hashed to select the timer shard to add the timer to */
+static timer_shard g_shards[NUM_SHARDS];
+
+/* Maintains a sorted list of timer shards (sorted by their min_deadline, i.e
+ * the deadline of the next timer in each shard).
+ * Access to this is protected by g_shared_mutables.mu */
+static timer_shard *g_shard_queue[NUM_SHARDS];
+
+/* Thread local variable that stores the deadline of the next timer the thread
+ * has last-seen. This is an optimization to prevent the thread from checking
+ * shared_mutables.min_timer (which requires acquiring shared_mutables.mu lock,
+ * an expensive operation) */
+GPR_TLS_DECL(g_last_seen_min_timer);
 
 struct shared_mutables {
+  /* The deadline of the next timer due across all timer shards */
   gpr_atm min_timer;
   /* Allow only one run_some_expired_timers at once */
   gpr_spinlock checker_mu;
   bool initialized;
-  /* Protects g_shard_queue */
+  /* Protects g_shard_queue (and the shared_mutables struct itself) */
   gpr_mu mu;
 } GPR_ALIGN_STRUCT(GPR_CACHELINE_SIZE);
 
 static struct shared_mutables g_shared_mutables = {
     .checker_mu = GPR_SPINLOCK_STATIC_INITIALIZER, .initialized = false,
 };
-static shard_type g_shards[NUM_SHARDS];
-/* Protected by g_shared_mutables.mu */
-static shard_type *g_shard_queue[NUM_SHARDS];
-
-GPR_TLS_DECL(g_last_seen_min_timer);
 
 static gpr_atm saturating_add(gpr_atm a, gpr_atm b) {
   if (a > GPR_ATM_MAX - b) {
@@ -99,10 +106,12 @@ static gpr_atm saturating_add(gpr_atm a, gpr_atm b) {
   return a + b;
 }
 
-static int run_some_expired_timers(grpc_exec_ctx *exec_ctx, gpr_atm now,
-                                   gpr_atm *next, grpc_error *error);
+static grpc_timer_check_result run_some_expired_timers(grpc_exec_ctx *exec_ctx,
+                                                       gpr_atm now,
+                                                       gpr_atm *next,
+                                                       grpc_error *error);
 
-static gpr_atm compute_min_deadline(shard_type *shard) {
+static gpr_atm compute_min_deadline(timer_shard *shard) {
   return grpc_timer_heap_is_empty(&shard->heap)
              ? saturating_add(shard->queue_deadline_cap, 1)
              : grpc_timer_heap_top(&shard->heap)->deadline;
@@ -116,11 +125,11 @@ void grpc_timer_list_init(grpc_exec_ctx *exec_ctx) {
   g_shared_mutables.min_timer = grpc_exec_ctx_now(exec_ctx);
   gpr_tls_init(&g_last_seen_min_timer);
   gpr_tls_set(&g_last_seen_min_timer, 0);
-  grpc_register_tracer("timer", &grpc_timer_trace);
-  grpc_register_tracer("timer_check", &grpc_timer_check_trace);
+  grpc_register_tracer(&grpc_timer_trace);
+  grpc_register_tracer(&grpc_timer_check_trace);
 
   for (i = 0; i < NUM_SHARDS; i++) {
-    shard_type *shard = &g_shards[i];
+    timer_shard *shard = &g_shards[i];
     gpr_mu_init(&shard->mu);
     grpc_time_averaged_stats_init(&shard->stats, 1.0 / ADD_DEADLINE_SCALE, 0.1,
                                   0.5);
@@ -139,7 +148,7 @@ void grpc_timer_list_shutdown(grpc_exec_ctx *exec_ctx) {
       exec_ctx, GPR_ATM_MAX, NULL,
       GRPC_ERROR_CREATE_FROM_STATIC_STRING("Timer list shutdown"));
   for (i = 0; i < NUM_SHARDS; i++) {
-    shard_type *shard = &g_shards[i];
+    timer_shard *shard = &g_shards[i];
     gpr_mu_destroy(&shard->mu);
     grpc_timer_heap_destroy(&shard->heap);
   }
@@ -161,7 +170,7 @@ static void list_remove(grpc_timer *timer) {
 }
 
 static void swap_adjacent_shards_in_queue(uint32_t first_shard_queue_index) {
-  shard_type *temp;
+  timer_shard *temp;
   temp = g_shard_queue[first_shard_queue_index];
   g_shard_queue[first_shard_queue_index] =
       g_shard_queue[first_shard_queue_index + 1];
@@ -172,7 +181,7 @@ static void swap_adjacent_shards_in_queue(uint32_t first_shard_queue_index) {
       first_shard_queue_index + 1;
 }
 
-static void note_deadline_change(shard_type *shard) {
+static void note_deadline_change(timer_shard *shard) {
   while (shard->shard_queue_index > 0 &&
          shard->min_deadline <
              g_shard_queue[shard->shard_queue_index - 1]->min_deadline) {
@@ -188,7 +197,7 @@ static void note_deadline_change(shard_type *shard) {
 void grpc_timer_init(grpc_exec_ctx *exec_ctx, grpc_timer *timer,
                      grpc_millis deadline, grpc_closure *closure) {
   int is_first_timer = 0;
-  shard_type *shard = &g_shards[GPR_HASH_POINTER(timer, NUM_SHARDS)];
+  timer_shard *shard = &g_shards[GPR_HASH_POINTER(timer, NUM_SHARDS)];
   timer->closure = closure;
 
   if (GRPC_TRACER_ON(grpc_timer_trace)) {
@@ -199,7 +208,7 @@ void grpc_timer_init(grpc_exec_ctx *exec_ctx, grpc_timer *timer,
 
   if (!g_shared_mutables.initialized) {
     timer->pending = false;
-    grpc_closure_sched(exec_ctx, timer->closure,
+    GRPC_CLOSURE_SCHED(exec_ctx, timer->closure,
                        GRPC_ERROR_CREATE_FROM_STATIC_STRING(
                            "Attempt to create timer before initialization"));
     return;
@@ -210,7 +219,7 @@ void grpc_timer_init(grpc_exec_ctx *exec_ctx, grpc_timer *timer,
   grpc_millis now = grpc_exec_ctx_now(exec_ctx);
   if (deadline <= now) {
     timer->pending = false;
-    grpc_closure_sched(exec_ctx, timer->closure, GRPC_ERROR_NONE);
+    GRPC_CLOSURE_SCHED(exec_ctx, timer->closure, GRPC_ERROR_NONE);
     gpr_mu_unlock(&shard->mu);
     /* early out */
     return;
@@ -272,14 +281,14 @@ void grpc_timer_cancel(grpc_exec_ctx *exec_ctx, grpc_timer *timer) {
     return;
   }
 
-  shard_type *shard = &g_shards[GPR_HASH_POINTER(timer, NUM_SHARDS)];
+  timer_shard *shard = &g_shards[GPR_HASH_POINTER(timer, NUM_SHARDS)];
   gpr_mu_lock(&shard->mu);
   if (GRPC_TRACER_ON(grpc_timer_trace)) {
     gpr_log(GPR_DEBUG, "TIMER %p: CANCEL pending=%s", timer,
             timer->pending ? "true" : "false");
   }
   if (timer->pending) {
-    grpc_closure_sched(exec_ctx, timer->closure, GRPC_ERROR_CANCELLED);
+    GRPC_CLOSURE_SCHED(exec_ctx, timer->closure, GRPC_ERROR_CANCELLED);
     timer->pending = false;
     if (timer->heap_index == INVALID_HEAP_INDEX) {
       list_remove(timer);
@@ -290,12 +299,12 @@ void grpc_timer_cancel(grpc_exec_ctx *exec_ctx, grpc_timer *timer) {
   gpr_mu_unlock(&shard->mu);
 }
 
-/* This is called when the queue is empty and "now" has reached the
-   queue_deadline_cap.  We compute a new queue deadline and then scan the map
-   for timers that fall at or under it.  Returns true if the queue is no
-   longer empty.
+/* Rebalances the timer shard by computing a new 'queue_deadline_cap' and moving
+   all relevant timers in shard->list (i.e timers with deadlines earlier than
+   'queue_deadline_cap') into into shard->heap.
+   Returns 'true' if shard->heap has atleast ONE element
    REQUIRES: shard->mu locked */
-static int refill_queue(shard_type *shard, gpr_atm now) {
+static int refill_heap(timer_shard *shard, gpr_atm now) {
   /* Compute the new queue window width and bound by the limits: */
   double computed_deadline_delta =
       grpc_time_averaged_stats_update_average(&shard->stats) *
@@ -332,7 +341,7 @@ static int refill_queue(shard_type *shard, gpr_atm now) {
 /* This pops the next non-cancelled timer with deadline <= now from the
    queue, or returns NULL if there isn't one.
    REQUIRES: shard->mu locked */
-static grpc_timer *pop_one(shard_type *shard, gpr_atm now) {
+static grpc_timer *pop_one(timer_shard *shard, gpr_atm now) {
   grpc_timer *timer;
   for (;;) {
     if (GRPC_TRACER_ON(grpc_timer_check_trace)) {
@@ -342,7 +351,7 @@ static grpc_timer *pop_one(shard_type *shard, gpr_atm now) {
     }
     if (grpc_timer_heap_is_empty(&shard->heap)) {
       if (now < shard->queue_deadline_cap) return NULL;
-      if (!refill_queue(shard, now)) return NULL;
+      if (!refill_heap(shard, now)) return NULL;
     }
     timer = grpc_timer_heap_top(&shard->heap);
     if (GRPC_TRACER_ON(grpc_timer_check_trace)) {
@@ -362,14 +371,14 @@ static grpc_timer *pop_one(shard_type *shard, gpr_atm now) {
 }
 
 /* REQUIRES: shard->mu unlocked */
-static size_t pop_timers(grpc_exec_ctx *exec_ctx, shard_type *shard,
+static size_t pop_timers(grpc_exec_ctx *exec_ctx, timer_shard *shard,
                          gpr_atm now, gpr_atm *new_min_deadline,
                          grpc_error *error) {
   size_t n = 0;
   grpc_timer *timer;
   gpr_mu_lock(&shard->mu);
   while ((timer = pop_one(shard, now))) {
-    grpc_closure_sched(exec_ctx, timer->closure, GRPC_ERROR_REF(error));
+    GRPC_CLOSURE_SCHED(exec_ctx, timer->closure, GRPC_ERROR_REF(error));
     n++;
   }
   *new_min_deadline = compute_min_deadline(shard);
@@ -377,19 +386,22 @@ static size_t pop_timers(grpc_exec_ctx *exec_ctx, shard_type *shard,
   return n;
 }
 
-static int run_some_expired_timers(grpc_exec_ctx *exec_ctx, gpr_atm now,
-                                   gpr_atm *next, grpc_error *error) {
-  size_t n = 0;
+static grpc_timer_check_result run_some_expired_timers(grpc_exec_ctx *exec_ctx,
+                                                       gpr_atm now,
+                                                       gpr_atm *next,
+                                                       grpc_error *error) {
+  grpc_timer_check_result result = GRPC_TIMERS_NOT_CHECKED;
 
   gpr_atm min_timer = gpr_atm_no_barrier_load(&g_shared_mutables.min_timer);
   gpr_tls_set(&g_last_seen_min_timer, min_timer);
   if (now < min_timer) {
     if (next != NULL) *next = GPR_MIN(*next, min_timer);
-    return 0;
+    return GRPC_TIMERS_CHECKED_AND_EMPTY;
   }
 
   if (gpr_spinlock_trylock(&g_shared_mutables.checker_mu)) {
     gpr_mu_lock(&g_shared_mutables.mu);
+    result = GRPC_TIMERS_CHECKED_AND_EMPTY;
 
     if (GRPC_TRACER_ON(grpc_timer_check_trace)) {
       gpr_log(GPR_DEBUG, "  .. shard[%d]->min_deadline = %" PRIdPTR,
@@ -404,14 +416,17 @@ static int run_some_expired_timers(grpc_exec_ctx *exec_ctx, gpr_atm now,
       /* For efficiency, we pop as many available timers as we can from the
          shard.  This may violate perfect timer deadline ordering, but that
          shouldn't be a big deal because we don't make ordering guarantees. */
-      n +=
-          pop_timers(exec_ctx, g_shard_queue[0], now, &new_min_deadline, error);
+      if (pop_timers(exec_ctx, g_shard_queue[0], now, &new_min_deadline,
+                     error) > 0) {
+        result = GRPC_TIMERS_FIRED;
+      }
 
       if (GRPC_TRACER_ON(grpc_timer_check_trace)) {
-        gpr_log(GPR_DEBUG, "  .. popped --> %" PRIdPTR
-                           ", shard[%d]->min_deadline %" PRIdPTR
-                           " --> %" PRIdPTR ", now=%" PRIdPTR,
-                n, (int)(g_shard_queue[0] - g_shards),
+        gpr_log(GPR_DEBUG,
+                "  .. result --> %d"
+                ", shard[%d]->min_deadline %" PRIdPTR " --> %" PRIdPTR
+                ", now=%" PRIdPTR,
+                result, (int)(g_shard_queue[0] - g_shards),
                 g_shard_queue[0]->min_deadline, new_min_deadline, now);
       }
 
@@ -432,25 +447,15 @@ static int run_some_expired_timers(grpc_exec_ctx *exec_ctx, gpr_atm now,
                              g_shard_queue[0]->min_deadline);
     gpr_mu_unlock(&g_shared_mutables.mu);
     gpr_spinlock_unlock(&g_shared_mutables.checker_mu);
-  } else if (next != NULL) {
-    /* TODO(ctiller): this forces calling code to do an short poll, and
-       then retry the timer check (because this time through the timer list was
-       contended).
-
-       We could reduce the cost here dramatically by keeping a count of how
-       many currently active pollers got through the uncontended case above
-       successfully, and waking up other pollers IFF that count drops to zero.
-
-       Once that count is in place, this entire else branch could disappear. */
-    *next = GPR_MIN(*next, now + 1);
   }
 
   GRPC_ERROR_UNREF(error);
 
-  return (int)n;
+  return result;
 }
 
-bool grpc_timer_check(grpc_exec_ctx *exec_ctx, grpc_millis *next) {
+grpc_timer_check_result grpc_timer_check(grpc_exec_ctx *exec_ctx,
+                                         grpc_millis *next) {
   // prelude
   grpc_millis now = grpc_exec_ctx_now(exec_ctx);
 
@@ -466,7 +471,7 @@ bool grpc_timer_check(grpc_exec_ctx *exec_ctx, grpc_millis *next) {
               "TIMER CHECK SKIP: now=%" PRIdPTR " min_timer=%" PRIdPTR, now,
               min_timer);
     }
-    return 0;
+    return GRPC_TIMERS_CHECKED_AND_EMPTY;
   }
 
   grpc_error *shutdown_error =
@@ -498,11 +503,10 @@ bool grpc_timer_check(grpc_exec_ctx *exec_ctx, grpc_millis *next) {
     } else {
       gpr_asprintf(&next_str, "%" PRIdPTR, *next);
     }
-    gpr_log(GPR_DEBUG, "TIMER CHECK END: %d timers triggered; next=%s", r,
-            next_str);
+    gpr_log(GPR_DEBUG, "TIMER CHECK END: r=%d; next=%s", r, next_str);
     gpr_free(next_str);
   }
-  return r > 0;
+  return r;
 }
 
 #endif /* GRPC_TIMER_USE_GENERIC */
diff --git a/src/core/lib/iomgr/timer_generic.h b/src/core/lib/iomgr/timer_generic.h
index c79a431aa0..72a4ac1f10 100644
--- a/src/core/lib/iomgr/timer_generic.h
+++ b/src/core/lib/iomgr/timer_generic.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/timer_heap.c b/src/core/lib/iomgr/timer_heap.c
index 03ccfe023a..a70e3942b2 100644
--- a/src/core/lib/iomgr/timer_heap.c
+++ b/src/core/lib/iomgr/timer_heap.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/timer_heap.h b/src/core/lib/iomgr/timer_heap.h
index 576c20e09a..0d64199ab9 100644
--- a/src/core/lib/iomgr/timer_heap.h
+++ b/src/core/lib/iomgr/timer_heap.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/timer_manager.c b/src/core/lib/iomgr/timer_manager.c
index 66ccf1d19a..751314c23f 100644
--- a/src/core/lib/iomgr/timer_manager.c
+++ b/src/core/lib/iomgr/timer_manager.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2017, Google Inc.
- * All rights reserved.
+ * Copyright 2017 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -65,10 +50,13 @@ static completed_thread *g_completed_threads;
 static bool g_kicked;
 // is there a thread waiting until the next timer should fire?
 static bool g_has_timed_waiter;
+// the deadline of the current timed waiter thread (only relevant if
+// g_has_timed_waiter is true)
+static grpc_millis g_timed_waiter_deadline;
 // generation counter to track which thread is waiting for the next timer
 static uint64_t g_timed_waiter_generation;
 
-static void timer_thread(void *unused);
+static void timer_thread(void *completed_thread_ptr);
 
 static void gc_completed_threads(void) {
   if (g_completed_threads != NULL) {
@@ -93,10 +81,17 @@ static void start_timer_thread_and_unlock(void) {
   if (GRPC_TRACER_ON(grpc_timer_check_trace)) {
     gpr_log(GPR_DEBUG, "Spawn timer thread");
   }
-  gpr_thd_id thd;
   gpr_thd_options opt = gpr_thd_options_default();
   gpr_thd_options_set_joinable(&opt);
-  gpr_thd_new(&thd, timer_thread, NULL, &opt);
+  completed_thread *ct = gpr_malloc(sizeof(*ct));
+  // The call to gpr_thd_new() has to be under the same lock used by
+  // gc_completed_threads(), particularly due to ct->t, which is written here
+  // (internally by gpr_thd_new) and read there. Otherwise it's possible for ct
+  // to leak through g_completed_threads and be freed in gc_completed_threads()
+  // before "&ct->t" is written to, causing a use-after-free.
+  gpr_mu_lock(&g_mu);
+  gpr_thd_new(&ct->t, timer_thread, ct, &opt);
+  gpr_mu_unlock(&g_mu);
 }
 
 void grpc_timer_manager_tick() {
@@ -106,86 +101,154 @@ void grpc_timer_manager_tick() {
   grpc_exec_ctx_finish(&exec_ctx);
 }
 
-static void timer_thread(void *unused) {
-  // this threads exec_ctx: we try to run things through to completion here
-  // since it's easy to spin up new threads
-  grpc_exec_ctx exec_ctx =
-      GRPC_EXEC_CTX_INITIALIZER(0, grpc_never_ready_to_finish, NULL);
-  for (;;) {
-    grpc_millis next = GRPC_MILLIS_INF_FUTURE;
-    // check timer state, updates next to the next time to run a check
-    if (grpc_timer_check(&exec_ctx, &next)) {
-      // if there's something to execute...
-      gpr_mu_lock(&g_mu);
-      // remove a waiter from the pool, and start another thread if necessary
-      --g_waiter_count;
-      if (g_waiter_count == 0 && g_threaded) {
-        start_timer_thread_and_unlock();
-      } else {
-        // if there's no thread waiting with a timeout, kick an existing waiter
-        // so that the next deadline is not missed
-        if (!g_has_timed_waiter) {
-          if (GRPC_TRACER_ON(grpc_timer_check_trace)) {
-            gpr_log(GPR_DEBUG, "kick untimed waiter");
-          }
-          gpr_cv_signal(&g_cv_wait);
-        }
-        gpr_mu_unlock(&g_mu);
+static void run_some_timers(grpc_exec_ctx *exec_ctx) {
+  // if there's something to execute...
+  gpr_mu_lock(&g_mu);
+  // remove a waiter from the pool, and start another thread if necessary
+  --g_waiter_count;
+  if (g_waiter_count == 0 && g_threaded) {
+    start_timer_thread_and_unlock();
+  } else {
+    // if there's no thread waiting with a timeout, kick an existing
+    // waiter so that the next deadline is not missed
+    if (!g_has_timed_waiter) {
+      if (GRPC_TRACER_ON(grpc_timer_check_trace)) {
+        gpr_log(GPR_DEBUG, "kick untimed waiter");
       }
-      // without our lock, flush the exec_ctx
-      grpc_exec_ctx_flush(&exec_ctx);
-      gpr_mu_lock(&g_mu);
-      // garbage collect any threads hanging out that are dead
-      gc_completed_threads();
-      // get ready to wait again
-      ++g_waiter_count;
-      gpr_mu_unlock(&g_mu);
-    } else {
-      gpr_mu_lock(&g_mu);
-      // if we're not threaded anymore, leave
-      if (!g_threaded) break;
-      // if there's no timed waiter, we should become one: that waiter waits
-      // only until the next timer should expire
-      // all other timers wait forever
-      uint64_t my_timed_waiter_generation = g_timed_waiter_generation - 1;
-      if (!g_has_timed_waiter) {
-        g_has_timed_waiter = true;
-        // we use a generation counter to track the timed waiter so we can
-        // cancel an existing one quickly (and when it actually times out it'll
-        // figure stuff out instead of incurring a wakeup)
+      gpr_cv_signal(&g_cv_wait);
+    }
+    gpr_mu_unlock(&g_mu);
+  }
+  // without our lock, flush the exec_ctx
+  grpc_exec_ctx_flush(exec_ctx);
+  gpr_mu_lock(&g_mu);
+  // garbage collect any threads hanging out that are dead
+  gc_completed_threads();
+  // get ready to wait again
+  ++g_waiter_count;
+  gpr_mu_unlock(&g_mu);
+}
+
+// wait until 'next' (or forever if there is already a timed waiter in the pool)
+// returns true if the thread should continue executing (false if it should
+// shutdown)
+static bool wait_until(grpc_exec_ctx *exec_ctx, grpc_millis next) {
+  gpr_mu_lock(&g_mu);
+  // if we're not threaded anymore, leave
+  if (!g_threaded) {
+    gpr_mu_unlock(&g_mu);
+    return false;
+  }
+
+  // If g_kicked is true at this point, it means there was a kick from the timer
+  // system that the timer-manager threads here missed. We cannot trust 'next'
+  // here any longer (since there might be an earlier deadline). So if g_kicked
+  // is true at this point, we should quickly exit this and get the next
+  // deadline from the timer system
+
+  if (!g_kicked) {
+    // if there's no timed waiter, we should become one: that waiter waits
+    // only until the next timer should expire. All other timers wait forever
+    //
+    // 'g_timed_waiter_generation' is a global generation counter. The idea here
+    // is that the thread becoming a timed-waiter increments and stores this
+    // global counter locally in 'my_timed_waiter_generation' before going to
+    // sleep. After waking up, if my_timed_waiter_generation ==
+    // g_timed_waiter_generation, it can be sure that it was the timed_waiter
+    // thread (and that no other thread took over while this was asleep)
+    //
+    // Initialize my_timed_waiter_generation to some value that is NOT equal to
+    // g_timed_waiter_generation
+    uint64_t my_timed_waiter_generation = g_timed_waiter_generation - 1;
+
+    /* If there's no timed waiter, we should become one: that waiter waits only
+       until the next timer should expire. All other timer threads wait forever
+       unless their 'next' is earlier than the current timed-waiter's deadline
+       (in which case the thread with earlier 'next' takes over as the new timed
+       waiter) */
+    if (next != GRPC_MILLIS_INF_FUTURE) {
+      if (!g_has_timed_waiter || (next < g_timed_waiter_deadline)) {
         my_timed_waiter_generation = ++g_timed_waiter_generation;
+        g_has_timed_waiter = true;
+        g_timed_waiter_deadline = next;
+
         if (GRPC_TRACER_ON(grpc_timer_check_trace)) {
-          gpr_log(GPR_DEBUG, "sleep for a while");
+          grpc_millis wait_time = next - grpc_exec_ctx_now(exec_ctx);
+          gpr_log(GPR_DEBUG, "sleep for a %" PRIdPTR " milliseconds",
+                  wait_time);
         }
-      } else {
+      } else {  // g_timed_waiter == true && next >= g_timed_waiter_deadline
         next = GRPC_MILLIS_INF_FUTURE;
+      }
+    }
+
+    if (GRPC_TRACER_ON(grpc_timer_check_trace) &&
+        next == GRPC_MILLIS_INF_FUTURE) {
+      gpr_log(GPR_DEBUG, "sleep until kicked");
+    }
+
+    gpr_cv_wait(&g_cv_wait, &g_mu,
+                grpc_millis_to_timespec(exec_ctx, next, GPR_CLOCK_REALTIME));
+
+    if (GRPC_TRACER_ON(grpc_timer_check_trace)) {
+      gpr_log(GPR_DEBUG, "wait ended: was_timed:%d kicked:%d",
+              my_timed_waiter_generation == g_timed_waiter_generation,
+              g_kicked);
+    }
+    // if this was the timed waiter, then we need to check timers, and flag
+    // that there's now no timed waiter... we'll look for a replacement if
+    // there's work to do after checking timers (code above)
+    if (my_timed_waiter_generation == g_timed_waiter_generation) {
+      g_has_timed_waiter = false;
+      g_timed_waiter_deadline = GRPC_MILLIS_INF_FUTURE;
+    }
+  }
+
+  // if this was a kick from the timer system, consume it (and don't stop
+  // this thread yet)
+  if (g_kicked) {
+    grpc_timer_consume_kick();
+    g_kicked = false;
+  }
+
+  gpr_mu_unlock(&g_mu);
+  return true;
+}
+
+static void timer_main_loop(grpc_exec_ctx *exec_ctx) {
+  for (;;) {
+    grpc_millis next = GRPC_MILLIS_INF_FUTURE;
+    // check timer state, updates next to the next time to run a check
+    switch (grpc_timer_check(exec_ctx, &next)) {
+      case GRPC_TIMERS_FIRED:
+        run_some_timers(exec_ctx);
+        break;
+      case GRPC_TIMERS_NOT_CHECKED:
+        /* This case only happens under contention, meaning more than one timer
+           manager thread checked timers concurrently.
+
+           If that happens, we're guaranteed that some other thread has just
+           checked timers, and this will avalanche into some other thread seeing
+           empty timers and doing a timed sleep.
+
+           Consequently, we can just sleep forever here and be happy at some
+           saved wakeup cycles. */
         if (GRPC_TRACER_ON(grpc_timer_check_trace)) {
-          gpr_log(GPR_DEBUG, "sleep until kicked");
+          gpr_log(GPR_DEBUG, "timers not checked: expect another thread to");
         }
-      }
-      gpr_cv_wait(&g_cv_wait, &g_mu,
-                  grpc_millis_to_timespec(&exec_ctx, next, GPR_CLOCK_REALTIME));
-      grpc_exec_ctx_invalidate_now(&exec_ctx);
-      if (GRPC_TRACER_ON(grpc_timer_check_trace)) {
-        gpr_log(GPR_DEBUG, "wait ended: was_timed:%d kicked:%d",
-                my_timed_waiter_generation == g_timed_waiter_generation,
-                g_kicked);
-      }
-      // if this was the timed waiter, then we need to check timers, and flag
-      // that there's now no timed waiter... we'll look for a replacement if
-      // there's work to do after checking timers (code above)
-      if (my_timed_waiter_generation == g_timed_waiter_generation) {
-        g_has_timed_waiter = false;
-      }
-      // if this was a kick from the timer system, consume it (and don't stop
-      // this thread yet)
-      if (g_kicked) {
-        grpc_timer_consume_kick();
-        g_kicked = false;
-      }
-      gpr_mu_unlock(&g_mu);
+        next = GRPC_MILLIS_INF_FUTURE;
+      /* fall through */
+      case GRPC_TIMERS_CHECKED_AND_EMPTY:
+        if (!wait_until(exec_ctx, next)) {
+          return;
+        }
+        break;
     }
   }
+}
+
+static void timer_thread_cleanup(completed_thread *ct) {
+  gpr_mu_lock(&g_mu);
   // terminate the thread: drop the waiter count, thread count, and let whomever
   // stopped the threading stuff know that we're done
   --g_waiter_count;
@@ -193,17 +256,24 @@ static void timer_thread(void *unused) {
   if (0 == g_thread_count) {
     gpr_cv_signal(&g_cv_shutdown);
   }
-  completed_thread *ct = gpr_malloc(sizeof(*ct));
-  ct->t = gpr_thd_currentid();
   ct->next = g_completed_threads;
   g_completed_threads = ct;
   gpr_mu_unlock(&g_mu);
-  grpc_exec_ctx_finish(&exec_ctx);
   if (GRPC_TRACER_ON(grpc_timer_check_trace)) {
     gpr_log(GPR_DEBUG, "End timer thread");
   }
 }
 
+static void timer_thread(void *completed_thread_ptr) {
+  // this threads exec_ctx: we try to run things through to completion here
+  // since it's easy to spin up new threads
+  grpc_exec_ctx exec_ctx =
+      GRPC_EXEC_CTX_INITIALIZER(0, grpc_never_ready_to_finish, NULL);
+  timer_main_loop(&exec_ctx);
+  grpc_exec_ctx_finish(&exec_ctx);
+  timer_thread_cleanup(completed_thread_ptr);
+}
+
 static void start_threads(void) {
   gpr_mu_lock(&g_mu);
   if (!g_threaded) {
@@ -224,6 +294,9 @@ void grpc_timer_manager_init(void) {
   g_waiter_count = 0;
   g_completed_threads = NULL;
 
+  g_has_timed_waiter = false;
+  g_timed_waiter_deadline = GRPC_MILLIS_INF_FUTURE;
+
   start_threads();
 }
 
@@ -269,6 +342,7 @@ void grpc_kick_poller(void) {
   gpr_mu_lock(&g_mu);
   g_kicked = true;
   g_has_timed_waiter = false;
+  g_timed_waiter_deadline = GRPC_MILLIS_INF_FUTURE;
   ++g_timed_waiter_generation;
   gpr_cv_signal(&g_cv_wait);
   gpr_mu_unlock(&g_mu);
diff --git a/src/core/lib/iomgr/timer_manager.h b/src/core/lib/iomgr/timer_manager.h
index 46729ccea6..0ba502928a 100644
--- a/src/core/lib/iomgr/timer_manager.h
+++ b/src/core/lib/iomgr/timer_manager.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2017, Google Inc.
- * All rights reserved.
+ * Copyright 2017 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/timer_uv.c b/src/core/lib/iomgr/timer_uv.c
index 2952e44b58..1ab82ef1d5 100644
--- a/src/core/lib/iomgr/timer_uv.c
+++ b/src/core/lib/iomgr/timer_uv.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -43,8 +28,9 @@
 
 #include <uv.h>
 
-grpc_tracer_flag grpc_timer_trace = GRPC_TRACER_INITIALIZER(false);
-grpc_tracer_flag grpc_timer_check_trace = GRPC_TRACER_INITIALIZER(false);
+grpc_tracer_flag grpc_timer_trace = GRPC_TRACER_INITIALIZER(false, "timer");
+grpc_tracer_flag grpc_timer_check_trace =
+    GRPC_TRACER_INITIALIZER(false, "timer_check");
 
 static void timer_close_callback(uv_handle_t *handle) { gpr_free(handle); }
 
@@ -59,7 +45,7 @@ void run_expired_timer(uv_timer_t *handle) {
   grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
   GPR_ASSERT(timer->pending);
   timer->pending = 0;
-  grpc_closure_sched(&exec_ctx, timer->closure, GRPC_ERROR_NONE);
+  GRPC_CLOSURE_SCHED(&exec_ctx, timer->closure, GRPC_ERROR_NONE);
   stop_uv_timer(handle);
   grpc_exec_ctx_finish(&exec_ctx);
 }
@@ -72,7 +58,7 @@ void grpc_timer_init(grpc_exec_ctx *exec_ctx, grpc_timer *timer,
   timer->closure = closure;
   if (gpr_time_cmp(deadline, now) <= 0) {
     timer->pending = 0;
-    grpc_closure_sched(exec_ctx, timer->closure, GRPC_ERROR_NONE);
+    GRPC_CLOSURE_SCHED(exec_ctx, timer->closure, GRPC_ERROR_NONE);
     return;
   }
   timer->pending = 1;
@@ -91,14 +77,14 @@ void grpc_timer_init(grpc_exec_ctx *exec_ctx, grpc_timer *timer,
 void grpc_timer_cancel(grpc_exec_ctx *exec_ctx, grpc_timer *timer) {
   if (timer->pending) {
     timer->pending = 0;
-    grpc_closure_sched(exec_ctx, timer->closure, GRPC_ERROR_CANCELLED);
+    GRPC_CLOSURE_SCHED(exec_ctx, timer->closure, GRPC_ERROR_CANCELLED);
     stop_uv_timer((uv_timer_t *)timer->uv_timer);
   }
 }
 
-bool grpc_timer_check(grpc_exec_ctx *exec_ctx, gpr_timespec now,
-                      gpr_timespec *next) {
-  return false;
+grpc_timer_check_result grpc_timer_check(grpc_exec_ctx *exec_ctx,
+                                         gpr_timespec now, gpr_timespec *next) {
+  return GRPC_TIMERS_NOT_CHECKED;
 }
 
 void grpc_timer_list_init(gpr_timespec now) {}
diff --git a/src/core/lib/iomgr/timer_uv.h b/src/core/lib/iomgr/timer_uv.h
index 9870cd4a5c..8a4c17c844 100644
--- a/src/core/lib/iomgr/timer_uv.h
+++ b/src/core/lib/iomgr/timer_uv.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/udp_server.c b/src/core/lib/iomgr/udp_server.c
index af70746064..54e7f417a7 100644
--- a/src/core/lib/iomgr/udp_server.c
+++ b/src/core/lib/iomgr/udp_server.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -171,7 +156,7 @@ static void dummy_cb(grpc_exec_ctx *exec_ctx, void *arg, grpc_error *error) {
 
 static void finish_shutdown(grpc_exec_ctx *exec_ctx, grpc_udp_server *s) {
   if (s->shutdown_complete != NULL) {
-    grpc_closure_sched(exec_ctx, s->shutdown_complete, GRPC_ERROR_NONE);
+    GRPC_CLOSURE_SCHED(exec_ctx, s->shutdown_complete, GRPC_ERROR_NONE);
   }
 
   gpr_mu_destroy(&s->mu);
@@ -216,13 +201,13 @@ static void deactivated_all_ports(grpc_exec_ctx *exec_ctx, grpc_udp_server *s) {
     for (sp = s->head; sp; sp = sp->next) {
       grpc_unlink_if_unix_domain_socket(&sp->addr);
 
-      grpc_closure_init(&sp->destroyed_closure, destroyed_port, s,
+      GRPC_CLOSURE_INIT(&sp->destroyed_closure, destroyed_port, s,
                         grpc_schedule_on_exec_ctx);
       if (!sp->orphan_notified) {
         /* Call the orphan_cb to signal that the FD is about to be closed and
          * should no longer be used. Because at this point, all listening ports
          * have been shutdown already, no need to shutdown again.*/
-        grpc_closure_init(&sp->orphan_fd_closure, dummy_cb, sp->emfd,
+        GRPC_CLOSURE_INIT(&sp->orphan_fd_closure, dummy_cb, sp->emfd,
                           grpc_schedule_on_exec_ctx);
         GPR_ASSERT(sp->orphan_cb);
         sp->orphan_cb(exec_ctx, sp->emfd, &sp->orphan_fd_closure,
@@ -255,7 +240,7 @@ void grpc_udp_server_destroy(grpc_exec_ctx *exec_ctx, grpc_udp_server *s,
       struct shutdown_fd_args *args = gpr_malloc(sizeof(*args));
       args->fd = sp->emfd;
       args->server_mu = &s->mu;
-      grpc_closure_init(&sp->orphan_fd_closure, shutdown_fd, args,
+      GRPC_CLOSURE_INIT(&sp->orphan_fd_closure, shutdown_fd, args,
                         grpc_schedule_on_exec_ctx);
       sp->orphan_cb(exec_ctx, sp->emfd, &sp->orphan_fd_closure,
                     sp->server->user_data);
@@ -540,11 +525,11 @@ void grpc_udp_server_start(grpc_exec_ctx *exec_ctx, grpc_udp_server *s,
     for (i = 0; i < pollset_count; i++) {
       grpc_pollset_add_fd(exec_ctx, pollsets[i], sp->emfd);
     }
-    grpc_closure_init(&sp->read_closure, on_read, sp,
+    GRPC_CLOSURE_INIT(&sp->read_closure, on_read, sp,
                       grpc_schedule_on_exec_ctx);
     grpc_fd_notify_on_read(exec_ctx, sp->emfd, &sp->read_closure);
 
-    grpc_closure_init(&sp->write_closure, on_write, sp,
+    GRPC_CLOSURE_INIT(&sp->write_closure, on_write, sp,
                       grpc_schedule_on_exec_ctx);
     grpc_fd_notify_on_write(exec_ctx, sp->emfd, &sp->write_closure);
 
diff --git a/src/core/lib/iomgr/udp_server.h b/src/core/lib/iomgr/udp_server.h
index 8006037644..881468ea2c 100644
--- a/src/core/lib/iomgr/udp_server.h
+++ b/src/core/lib/iomgr/udp_server.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/unix_sockets_posix.c b/src/core/lib/iomgr/unix_sockets_posix.c
index 281865aece..0c8627c8c6 100644
--- a/src/core/lib/iomgr/unix_sockets_posix.c
+++ b/src/core/lib/iomgr/unix_sockets_posix.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 #include "src/core/lib/iomgr/port.h"
diff --git a/src/core/lib/iomgr/unix_sockets_posix.h b/src/core/lib/iomgr/unix_sockets_posix.h
index 21afd3aa15..25b64b3eec 100644
--- a/src/core/lib/iomgr/unix_sockets_posix.h
+++ b/src/core/lib/iomgr/unix_sockets_posix.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/unix_sockets_posix_noop.c b/src/core/lib/iomgr/unix_sockets_posix_noop.c
index b9602cbf8b..e46b1c003d 100644
--- a/src/core/lib/iomgr/unix_sockets_posix_noop.c
+++ b/src/core/lib/iomgr/unix_sockets_posix_noop.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/wakeup_fd_cv.c b/src/core/lib/iomgr/wakeup_fd_cv.c
index da4c2870cd..075a0b6426 100644
--- a/src/core/lib/iomgr/wakeup_fd_cv.c
+++ b/src/core/lib/iomgr/wakeup_fd_cv.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/wakeup_fd_cv.h b/src/core/lib/iomgr/wakeup_fd_cv.h
index ac16be1750..c5dcdc9746 100644
--- a/src/core/lib/iomgr/wakeup_fd_cv.h
+++ b/src/core/lib/iomgr/wakeup_fd_cv.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/wakeup_fd_eventfd.c b/src/core/lib/iomgr/wakeup_fd_eventfd.c
index 373e21d3e1..81cb7ee280 100644
--- a/src/core/lib/iomgr/wakeup_fd_eventfd.c
+++ b/src/core/lib/iomgr/wakeup_fd_eventfd.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/wakeup_fd_nospecial.c b/src/core/lib/iomgr/wakeup_fd_nospecial.c
index 611bced029..4c20b8c1b7 100644
--- a/src/core/lib/iomgr/wakeup_fd_nospecial.c
+++ b/src/core/lib/iomgr/wakeup_fd_nospecial.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/wakeup_fd_pipe.c b/src/core/lib/iomgr/wakeup_fd_pipe.c
index e186d63683..4189488f8a 100644
--- a/src/core/lib/iomgr/wakeup_fd_pipe.c
+++ b/src/core/lib/iomgr/wakeup_fd_pipe.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/wakeup_fd_pipe.h b/src/core/lib/iomgr/wakeup_fd_pipe.h
index 8972efc270..f860406bda 100644
--- a/src/core/lib/iomgr/wakeup_fd_pipe.h
+++ b/src/core/lib/iomgr/wakeup_fd_pipe.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/wakeup_fd_posix.c b/src/core/lib/iomgr/wakeup_fd_posix.c
index 85526402bd..25daa7d3fb 100644
--- a/src/core/lib/iomgr/wakeup_fd_posix.c
+++ b/src/core/lib/iomgr/wakeup_fd_posix.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/wakeup_fd_posix.h b/src/core/lib/iomgr/wakeup_fd_posix.h
index c8dd242c75..a9584d0d48 100644
--- a/src/core/lib/iomgr/wakeup_fd_posix.h
+++ b/src/core/lib/iomgr/wakeup_fd_posix.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/iomgr/workqueue.h b/src/core/lib/iomgr/workqueue.h
deleted file mode 100644
index 371b0f55dc..0000000000
--- a/src/core/lib/iomgr/workqueue.h
+++ /dev/null
@@ -1,87 +0,0 @@
-/*
- *
- * Copyright 2015, Google Inc.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
- *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- *
- */
-
-#ifndef GRPC_CORE_LIB_IOMGR_WORKQUEUE_H
-#define GRPC_CORE_LIB_IOMGR_WORKQUEUE_H
-
-#include "src/core/lib/iomgr/closure.h"
-#include "src/core/lib/iomgr/exec_ctx.h"
-#include "src/core/lib/iomgr/iomgr.h"
-#include "src/core/lib/iomgr/pollset.h"
-#include "src/core/lib/iomgr/pollset_set.h"
-#include "src/core/lib/iomgr/port.h"
-
-#ifdef GPR_WINDOWS
-#include "src/core/lib/iomgr/workqueue_windows.h"
-#endif
-
-/* grpc_workqueue is forward declared in exec_ctx.h */
-
-/* Reference counting functions. Use the macro's always
-   (GRPC_WORKQUEUE_{REF,UNREF}).
-
-   Pass in a descriptive reason string for reffing/unreffing as the last
-   argument to each macro. When GRPC_WORKQUEUE_REFCOUNT_DEBUG is defined, that
-   string will be printed alongside the refcount. When it is not defined, the
-   string will be discarded at compilation time. */
-
-/*#define GRPC_WORKQUEUE_REFCOUNT_DEBUG*/
-#ifdef GRPC_WORKQUEUE_REFCOUNT_DEBUG
-#define GRPC_WORKQUEUE_REF(p, r) \
-  grpc_workqueue_ref((p), __FILE__, __LINE__, (r))
-#define GRPC_WORKQUEUE_UNREF(exec_ctx, p, r) \
-  grpc_workqueue_unref((exec_ctx), (p), __FILE__, __LINE__, (r))
-grpc_workqueue *grpc_workqueue_ref(grpc_workqueue *workqueue, const char *file,
-                                   int line, const char *reason);
-void grpc_workqueue_unref(grpc_exec_ctx *exec_ctx, grpc_workqueue *workqueue,
-                          const char *file, int line, const char *reason);
-#else
-#define GRPC_WORKQUEUE_REF(p, r) grpc_workqueue_ref((p))
-#define GRPC_WORKQUEUE_UNREF(cl, p, r) grpc_workqueue_unref((cl), (p))
-grpc_workqueue *grpc_workqueue_ref(grpc_workqueue *workqueue);
-void grpc_workqueue_unref(grpc_exec_ctx *exec_ctx, grpc_workqueue *workqueue);
-#endif
-
-/** Fetch the workqueue closure scheduler. Items added to a work queue will be
-    started in approximately the order they were enqueued, on some thread that
-    may or may not be the current thread. Successive closures enqueued onto a
-    workqueue MAY be executed concurrently.
-
-    It is generally more expensive to add a closure to a workqueue than to the
-    execution context, both in terms of CPU work and in execution latency.
-
-    Use work queues when it's important that other threads be given a chance to
-    tackle some workload. */
-grpc_closure_scheduler *grpc_workqueue_scheduler(grpc_workqueue *workqueue);
-
-#endif /* GRPC_CORE_LIB_IOMGR_WORKQUEUE_H */
diff --git a/src/core/lib/iomgr/workqueue_uv.c b/src/core/lib/iomgr/workqueue_uv.c
deleted file mode 100644
index 4d61b40912..0000000000
--- a/src/core/lib/iomgr/workqueue_uv.c
+++ /dev/null
@@ -1,65 +0,0 @@
-/*
- *
- * Copyright 2016, Google Inc.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
- *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- *
- */
-
-#include "src/core/lib/iomgr/port.h"
-
-#ifdef GRPC_UV
-
-#include "src/core/lib/iomgr/workqueue.h"
-
-// Minimal implementation of grpc_workqueue for libuv
-// Works by directly enqueuing workqueue items onto the current execution
-// context, which is at least correct, if not performant or in the spirit of
-// workqueues.
-
-void grpc_workqueue_flush(grpc_exec_ctx *exec_ctx, grpc_workqueue *workqueue) {}
-
-#ifdef GRPC_WORKQUEUE_REFCOUNT_DEBUG
-grpc_workqueue *grpc_workqueue_ref(grpc_workqueue *workqueue, const char *file,
-                                   int line, const char *reason) {
-  return workqueue;
-}
-void grpc_workqueue_unref(grpc_exec_ctx *exec_ctx, grpc_workqueue *workqueue,
-                          const char *file, int line, const char *reason) {}
-#else
-grpc_workqueue *grpc_workqueue_ref(grpc_workqueue *workqueue) {
-  return workqueue;
-}
-void grpc_workqueue_unref(grpc_exec_ctx *exec_ctx, grpc_workqueue *workqueue) {}
-#endif
-
-grpc_closure_scheduler *grpc_workqueue_scheduler(grpc_workqueue *workqueue) {
-  return grpc_schedule_on_exec_ctx;
-}
-
-#endif /* GPR_UV */
diff --git a/src/core/lib/iomgr/workqueue_uv.h b/src/core/lib/iomgr/workqueue_uv.h
deleted file mode 100644
index be3f8e4d93..0000000000
--- a/src/core/lib/iomgr/workqueue_uv.h
+++ /dev/null
@@ -1,37 +0,0 @@
-/*
- *
- * Copyright 2016, Google Inc.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
- *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- *
- */
-
-#ifndef GRPC_CORE_LIB_IOMGR_WORKQUEUE_UV_H
-#define GRPC_CORE_LIB_IOMGR_WORKQUEUE_UV_H
-
-#endif /* GRPC_CORE_LIB_IOMGR_WORKQUEUE_UV_H */
diff --git a/src/core/lib/iomgr/workqueue_windows.c b/src/core/lib/iomgr/workqueue_windows.c
deleted file mode 100644
index 234b47cdf5..0000000000
--- a/src/core/lib/iomgr/workqueue_windows.c
+++ /dev/null
@@ -1,63 +0,0 @@
-/*
- *
- * Copyright 2015, Google Inc.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
- *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- *
- */
-
-#include <grpc/support/port_platform.h>
-
-#ifdef GPR_WINDOWS
-
-#include "src/core/lib/iomgr/workqueue.h"
-
-// Minimal implementation of grpc_workqueue for Windows
-// Works by directly enqueuing workqueue items onto the current execution
-// context, which is at least correct, if not performant or in the spirit of
-// workqueues.
-
-#ifdef GRPC_WORKQUEUE_REFCOUNT_DEBUG
-grpc_workqueue *grpc_workqueue_ref(grpc_workqueue *workqueue, const char *file,
-                                   int line, const char *reason) {
-  return workqueue;
-}
-void grpc_workqueue_unref(grpc_exec_ctx *exec_ctx, grpc_workqueue *workqueue,
-                          const char *file, int line, const char *reason) {}
-#else
-grpc_workqueue *grpc_workqueue_ref(grpc_workqueue *workqueue) {
-  return workqueue;
-}
-void grpc_workqueue_unref(grpc_exec_ctx *exec_ctx, grpc_workqueue *workqueue) {}
-#endif
-
-grpc_closure_scheduler *grpc_workqueue_scheduler(grpc_workqueue *workqueue) {
-  return grpc_schedule_on_exec_ctx;
-}
-
-#endif /* GPR_WINDOWS */
diff --git a/src/core/lib/iomgr/workqueue_windows.h b/src/core/lib/iomgr/workqueue_windows.h
deleted file mode 100644
index e5d59130bb..0000000000
--- a/src/core/lib/iomgr/workqueue_windows.h
+++ /dev/null
@@ -1,37 +0,0 @@
-/*
- *
- * Copyright 2015, Google Inc.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
- *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- *
- */
-
-#ifndef GRPC_CORE_LIB_IOMGR_WORKQUEUE_WINDOWS_H
-#define GRPC_CORE_LIB_IOMGR_WORKQUEUE_WINDOWS_H
-
-#endif /* GRPC_CORE_LIB_IOMGR_WORKQUEUE_WINDOWS_H */
diff --git a/src/core/lib/json/json.c b/src/core/lib/json/json.c
index 5f7e4ec042..25eee05532 100644
--- a/src/core/lib/json/json.c
+++ b/src/core/lib/json/json.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/json/json.h b/src/core/lib/json/json.h
index 7111db0b52..bbd43025eb 100644
--- a/src/core/lib/json/json.h
+++ b/src/core/lib/json/json.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/json/json_common.h b/src/core/lib/json/json_common.h
index fa13088be9..bfa2ba32be 100644
--- a/src/core/lib/json/json_common.h
+++ b/src/core/lib/json/json_common.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/json/json_reader.c b/src/core/lib/json/json_reader.c
index 5b42ca53ff..75f59e0912 100644
--- a/src/core/lib/json/json_reader.c
+++ b/src/core/lib/json/json_reader.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015-2016, Google Inc.
- * All rights reserved.
+ * Copyright 2015-2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/json/json_reader.h b/src/core/lib/json/json_reader.h
index e0322c5507..577fbbbaf6 100644
--- a/src/core/lib/json/json_reader.h
+++ b/src/core/lib/json/json_reader.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/json/json_string.c b/src/core/lib/json/json_string.c
index 4af7ee7179..65b5f0f482 100644
--- a/src/core/lib/json/json_string.c
+++ b/src/core/lib/json/json_string.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/json/json_writer.c b/src/core/lib/json/json_writer.c
index b6a17f41e8..eab1bff7a6 100644
--- a/src/core/lib/json/json_writer.c
+++ b/src/core/lib/json/json_writer.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/json/json_writer.h b/src/core/lib/json/json_writer.h
index faeb41d031..8779039d42 100644
--- a/src/core/lib/json/json_writer.h
+++ b/src/core/lib/json/json_writer.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/profiling/basic_timers.c b/src/core/lib/profiling/basic_timers.c
index bc8e27714c..c7645b74f2 100644
--- a/src/core/lib/profiling/basic_timers.c
+++ b/src/core/lib/profiling/basic_timers.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/profiling/stap_timers.c b/src/core/lib/profiling/stap_timers.c
index 25e38e6d99..c86d74f058 100644
--- a/src/core/lib/profiling/stap_timers.c
+++ b/src/core/lib/profiling/stap_timers.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/profiling/timers.h b/src/core/lib/profiling/timers.h
index 621cdbf656..58e6659e6d 100644
--- a/src/core/lib/profiling/timers.h
+++ b/src/core/lib/profiling/timers.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/security/context/security_context.c b/src/core/lib/security/context/security_context.c
index d29fc55ea0..8fff2c92c5 100644
--- a/src/core/lib/security/context/security_context.c
+++ b/src/core/lib/security/context/security_context.c
@@ -1,38 +1,24 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
 #include <string.h>
 
+#include "src/core/lib/channel/channel_args.h"
 #include "src/core/lib/security/context/security_context.h"
 #include "src/core/lib/support/string.h"
 #include "src/core/lib/surface/api_trace.h"
@@ -43,6 +29,11 @@
 #include <grpc/support/log.h>
 #include <grpc/support/string_util.h>
 
+#ifndef NDEBUG
+grpc_tracer_flag grpc_trace_auth_context_refcount =
+    GRPC_TRACER_INITIALIZER(false, "auth_context_refcount");
+#endif
+
 /* --- grpc_call --- */
 
 grpc_call_error grpc_call_set_credentials(grpc_call *call,
@@ -136,14 +127,17 @@ grpc_auth_context *grpc_auth_context_create(grpc_auth_context *chained) {
   return ctx;
 }
 
-#ifdef GRPC_AUTH_CONTEXT_REFCOUNT_DEBUG
+#ifndef NDEBUG
 grpc_auth_context *grpc_auth_context_ref(grpc_auth_context *ctx,
                                          const char *file, int line,
                                          const char *reason) {
   if (ctx == NULL) return NULL;
-  gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
-          "AUTH_CONTEXT:%p   ref %d -> %d %s", ctx, (int)ctx->refcount.count,
-          (int)ctx->refcount.count + 1, reason);
+  if (GRPC_TRACER_ON(grpc_trace_auth_context_refcount)) {
+    gpr_atm val = gpr_atm_no_barrier_load(&ctx->refcount.count);
+    gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
+            "AUTH_CONTEXT:%p   ref %" PRIdPTR " -> %" PRIdPTR " %s", ctx, val,
+            val + 1, reason);
+  }
 #else
 grpc_auth_context *grpc_auth_context_ref(grpc_auth_context *ctx) {
   if (ctx == NULL) return NULL;
@@ -152,13 +146,16 @@ grpc_auth_context *grpc_auth_context_ref(grpc_auth_context *ctx) {
   return ctx;
 }
 
-#ifdef GRPC_AUTH_CONTEXT_REFCOUNT_DEBUG
+#ifndef NDEBUG
 void grpc_auth_context_unref(grpc_auth_context *ctx, const char *file, int line,
                              const char *reason) {
   if (ctx == NULL) return;
-  gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
-          "AUTH_CONTEXT:%p unref %d -> %d %s", ctx, (int)ctx->refcount.count,
-          (int)ctx->refcount.count - 1, reason);
+  if (GRPC_TRACER_ON(grpc_trace_auth_context_refcount)) {
+    gpr_atm val = gpr_atm_no_barrier_load(&ctx->refcount.count);
+    gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
+            "AUTH_CONTEXT:%p unref %" PRIdPTR " -> %" PRIdPTR " %s", ctx, val,
+            val - 1, reason);
+  }
 #else
 void grpc_auth_context_unref(grpc_auth_context *ctx) {
   if (ctx == NULL) return;
@@ -319,13 +316,8 @@ static const grpc_arg_pointer_vtable auth_context_pointer_vtable = {
     auth_context_pointer_cmp};
 
 grpc_arg grpc_auth_context_to_arg(grpc_auth_context *p) {
-  grpc_arg arg;
-  memset(&arg, 0, sizeof(grpc_arg));
-  arg.type = GRPC_ARG_POINTER;
-  arg.key = GRPC_AUTH_CONTEXT_ARG;
-  arg.value.pointer.p = p;
-  arg.value.pointer.vtable = &auth_context_pointer_vtable;
-  return arg;
+  return grpc_channel_arg_pointer_create(GRPC_AUTH_CONTEXT_ARG, p,
+                                         &auth_context_pointer_vtable);
 }
 
 grpc_auth_context *grpc_auth_context_from_arg(const grpc_arg *arg) {
diff --git a/src/core/lib/security/context/security_context.h b/src/core/lib/security/context/security_context.h
index 1e131a0c23..0df39257a7 100644
--- a/src/core/lib/security/context/security_context.h
+++ b/src/core/lib/security/context/security_context.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -37,6 +22,10 @@
 #include "src/core/lib/iomgr/pollset.h"
 #include "src/core/lib/security/credentials/credentials.h"
 
+#ifndef NDEBUG
+extern grpc_tracer_flag grpc_trace_auth_context_refcount;
+#endif
+
 #ifdef __cplusplus
 extern "C" {
 #endif
@@ -65,7 +54,7 @@ struct grpc_auth_context {
 grpc_auth_context *grpc_auth_context_create(grpc_auth_context *chained);
 
 /* Refcounting. */
-#ifdef GRPC_AUTH_CONTEXT_REFCOUNT_DEBUG
+#ifndef NDEBUG
 #define GRPC_AUTH_CONTEXT_REF(p, r) \
   grpc_auth_context_ref((p), __FILE__, __LINE__, (r))
 #define GRPC_AUTH_CONTEXT_UNREF(p, r) \
diff --git a/src/core/lib/security/credentials/composite/composite_credentials.c b/src/core/lib/security/credentials/composite/composite_credentials.c
index e497b9f657..77d7b04627 100644
--- a/src/core/lib/security/credentials/composite/composite_credentials.c
+++ b/src/core/lib/security/credentials/composite/composite_credentials.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015-2016, Google Inc.
- * All rights reserved.
+ * Copyright 2015-2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/security/credentials/composite/composite_credentials.h b/src/core/lib/security/credentials/composite/composite_credentials.h
index f8425c2b76..3076afcb7e 100644
--- a/src/core/lib/security/credentials/composite/composite_credentials.h
+++ b/src/core/lib/security/credentials/composite/composite_credentials.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/security/credentials/credentials.c b/src/core/lib/security/credentials/credentials.c
index d89da47fc1..b1f1e82076 100644
--- a/src/core/lib/security/credentials/credentials.c
+++ b/src/core/lib/security/credentials/credentials.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -174,12 +159,8 @@ static const grpc_arg_pointer_vtable credentials_pointer_vtable = {
 
 grpc_arg grpc_channel_credentials_to_arg(
     grpc_channel_credentials *credentials) {
-  grpc_arg result;
-  result.type = GRPC_ARG_POINTER;
-  result.key = GRPC_ARG_CHANNEL_CREDENTIALS;
-  result.value.pointer.vtable = &credentials_pointer_vtable;
-  result.value.pointer.p = credentials;
-  return result;
+  return grpc_channel_arg_pointer_create(
+      GRPC_ARG_CHANNEL_CREDENTIALS, credentials, &credentials_pointer_vtable);
 }
 
 grpc_channel_credentials *grpc_channel_credentials_from_arg(
@@ -275,13 +256,8 @@ static const grpc_arg_pointer_vtable cred_ptr_vtable = {
     server_credentials_pointer_cmp};
 
 grpc_arg grpc_server_credentials_to_arg(grpc_server_credentials *p) {
-  grpc_arg arg;
-  memset(&arg, 0, sizeof(grpc_arg));
-  arg.type = GRPC_ARG_POINTER;
-  arg.key = GRPC_SERVER_CREDENTIALS_ARG;
-  arg.value.pointer.p = p;
-  arg.value.pointer.vtable = &cred_ptr_vtable;
-  return arg;
+  return grpc_channel_arg_pointer_create(GRPC_SERVER_CREDENTIALS_ARG, p,
+                                         &cred_ptr_vtable);
 }
 
 grpc_server_credentials *grpc_server_credentials_from_arg(const grpc_arg *arg) {
diff --git a/src/core/lib/security/credentials/credentials.h b/src/core/lib/security/credentials/credentials.h
index 89b8e3c0b3..c45c2e957c 100644
--- a/src/core/lib/security/credentials/credentials.h
+++ b/src/core/lib/security/credentials/credentials.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/security/credentials/credentials_metadata.c b/src/core/lib/security/credentials/credentials_metadata.c
index f11cc58786..fcfdd52d20 100644
--- a/src/core/lib/security/credentials/credentials_metadata.c
+++ b/src/core/lib/security/credentials/credentials_metadata.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/security/credentials/fake/fake_credentials.c b/src/core/lib/security/credentials/fake/fake_credentials.c
index 3fdb67fb91..67e74f7b92 100644
--- a/src/core/lib/security/credentials/fake/fake_credentials.c
+++ b/src/core/lib/security/credentials/fake/fake_credentials.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -93,11 +78,8 @@ grpc_server_credentials *grpc_fake_transport_security_server_credentials_create(
 }
 
 grpc_arg grpc_fake_transport_expected_targets_arg(char *expected_targets) {
-  grpc_arg arg;
-  arg.type = GRPC_ARG_STRING;
-  arg.key = GRPC_ARG_FAKE_SECURITY_EXPECTED_TARGETS;
-  arg.value.string = expected_targets;
-  return arg;
+  return grpc_channel_arg_string_create(GRPC_ARG_FAKE_SECURITY_EXPECTED_TARGETS,
+                                        expected_targets);
 }
 
 const char *grpc_fake_transport_get_expected_targets(
@@ -138,8 +120,8 @@ static void md_only_test_get_request_metadata(
   if (c->is_async) {
     grpc_credentials_metadata_request *cb_arg =
         grpc_credentials_metadata_request_create(creds, cb, user_data);
-    grpc_closure_sched(exec_ctx,
-                       grpc_closure_create(on_simulated_token_fetch_done,
+    GRPC_CLOSURE_SCHED(exec_ctx,
+                       GRPC_CLOSURE_CREATE(on_simulated_token_fetch_done,
                                            cb_arg, grpc_executor_scheduler),
                        GRPC_ERROR_NONE);
   } else {
diff --git a/src/core/lib/security/credentials/fake/fake_credentials.h b/src/core/lib/security/credentials/fake/fake_credentials.h
index a28b545a67..fae7a6a9c4 100644
--- a/src/core/lib/security/credentials/fake/fake_credentials.h
+++ b/src/core/lib/security/credentials/fake/fake_credentials.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/security/credentials/google_default/credentials_generic.c b/src/core/lib/security/credentials/google_default/credentials_generic.c
index d13d8c5200..4f79718f3d 100644
--- a/src/core/lib/security/credentials/google_default/credentials_generic.c
+++ b/src/core/lib/security/credentials/google_default/credentials_generic.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/security/credentials/google_default/google_default_credentials.c b/src/core/lib/security/credentials/google_default/google_default_credentials.c
index f0807ab7ea..c83ecd088d 100644
--- a/src/core/lib/security/credentials/google_default/google_default_credentials.c
+++ b/src/core/lib/security/credentials/google_default/google_default_credentials.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -130,7 +115,7 @@ static int is_stack_running_on_compute_engine(grpc_exec_ctx *exec_ctx) {
   grpc_httpcli_get(
       exec_ctx, &context, &detector.pollent, resource_quota, &request,
       grpc_exec_ctx_now(exec_ctx) + max_detection_delay,
-      grpc_closure_create(on_compute_engine_detection_http_response, &detector,
+      GRPC_CLOSURE_CREATE(on_compute_engine_detection_http_response, &detector,
                           grpc_schedule_on_exec_ctx),
       &detector.response);
   grpc_resource_quota_unref_internal(exec_ctx, resource_quota);
@@ -154,7 +139,7 @@ static int is_stack_running_on_compute_engine(grpc_exec_ctx *exec_ctx) {
   gpr_mu_unlock(g_polling_mu);
 
   grpc_httpcli_context_destroy(exec_ctx, &context);
-  grpc_closure_init(&destroy_closure, destroy_pollset,
+  GRPC_CLOSURE_INIT(&destroy_closure, destroy_pollset,
                     grpc_polling_entity_pollset(&detector.pollent),
                     grpc_schedule_on_exec_ctx);
   grpc_pollset_shutdown(exec_ctx,
diff --git a/src/core/lib/security/credentials/google_default/google_default_credentials.h b/src/core/lib/security/credentials/google_default/google_default_credentials.h
index b55546ded0..c3755e01a6 100644
--- a/src/core/lib/security/credentials/google_default/google_default_credentials.h
+++ b/src/core/lib/security/credentials/google_default/google_default_credentials.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/security/credentials/iam/iam_credentials.c b/src/core/lib/security/credentials/iam/iam_credentials.c
index 393a433f2e..4b32c5a047 100644
--- a/src/core/lib/security/credentials/iam/iam_credentials.c
+++ b/src/core/lib/security/credentials/iam/iam_credentials.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/security/credentials/iam/iam_credentials.h b/src/core/lib/security/credentials/iam/iam_credentials.h
index af54faa586..fff3c6d2ca 100644
--- a/src/core/lib/security/credentials/iam/iam_credentials.h
+++ b/src/core/lib/security/credentials/iam/iam_credentials.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/security/credentials/jwt/json_token.c b/src/core/lib/security/credentials/jwt/json_token.c
index aa905725fc..fff71255a5 100644
--- a/src/core/lib/security/credentials/jwt/json_token.c
+++ b/src/core/lib/security/credentials/jwt/json_token.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/security/credentials/jwt/json_token.h b/src/core/lib/security/credentials/jwt/json_token.h
index c13eb55803..e50790ef2e 100644
--- a/src/core/lib/security/credentials/jwt/json_token.h
+++ b/src/core/lib/security/credentials/jwt/json_token.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/security/credentials/jwt/jwt_credentials.c b/src/core/lib/security/credentials/jwt/jwt_credentials.c
index 0e7c1afb02..4357657def 100644
--- a/src/core/lib/security/credentials/jwt/jwt_credentials.c
+++ b/src/core/lib/security/credentials/jwt/jwt_credentials.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -140,6 +125,13 @@ grpc_service_account_jwt_access_credentials_create_from_auth_json_key(
   gpr_ref_init(&c->base.refcount, 1);
   c->base.vtable = &jwt_vtable;
   c->key = key;
+  gpr_timespec max_token_lifetime = grpc_max_auth_token_lifetime();
+  if (gpr_time_cmp(token_lifetime, max_token_lifetime) > 0) {
+    gpr_log(GPR_INFO,
+            "Cropping token lifetime to maximum allowed value (%d secs).",
+            (int)max_token_lifetime.tv_sec);
+    token_lifetime = grpc_max_auth_token_lifetime();
+  }
   c->jwt_lifetime = token_lifetime;
   gpr_mu_init(&c->cache_mu);
   jwt_reset_cache(exec_ctx, c);
diff --git a/src/core/lib/security/credentials/jwt/jwt_credentials.h b/src/core/lib/security/credentials/jwt/jwt_credentials.h
index 39b7aeafe8..6e461f1715 100644
--- a/src/core/lib/security/credentials/jwt/jwt_credentials.h
+++ b/src/core/lib/security/credentials/jwt/jwt_credentials.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/security/credentials/jwt/jwt_verifier.c b/src/core/lib/security/credentials/jwt/jwt_verifier.c
index c7fea6c2e6..2e739ee26e 100644
--- a/src/core/lib/security/credentials/jwt/jwt_verifier.c
+++ b/src/core/lib/security/credentials/jwt/jwt_verifier.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -477,6 +462,35 @@ static BIGNUM *bignum_from_base64(grpc_exec_ctx *exec_ctx, const char *b64) {
   return result;
 }
 
+#if OPENSSL_VERSION_NUMBER < 0x10100000L
+
+// Provide compatibility across OpenSSL 1.02 and 1.1.
+static int RSA_set0_key(RSA *r, BIGNUM *n, BIGNUM *e, BIGNUM *d) {
+  /* If the fields n and e in r are NULL, the corresponding input
+   * parameters MUST be non-NULL for n and e.  d may be
+   * left NULL (in case only the public key is used).
+   */
+  if ((r->n == NULL && n == NULL) || (r->e == NULL && e == NULL)) {
+    return 0;
+  }
+
+  if (n != NULL) {
+    BN_free(r->n);
+    r->n = n;
+  }
+  if (e != NULL) {
+    BN_free(r->e);
+    r->e = e;
+  }
+  if (d != NULL) {
+    BN_free(r->d);
+    r->d = d;
+  }
+
+  return 1;
+}
+#endif  // OPENSSL_VERSION_NUMBER < 0x10100000L
+
 static EVP_PKEY *pkey_from_jwk(grpc_exec_ctx *exec_ctx, const grpc_json *json,
                                const char *kty) {
   const grpc_json *key_prop;
@@ -493,21 +507,27 @@ static EVP_PKEY *pkey_from_jwk(grpc_exec_ctx *exec_ctx, const grpc_json *json,
     gpr_log(GPR_ERROR, "Could not create rsa key.");
     goto end;
   }
+  BIGNUM *tmp_n = NULL;
+  BIGNUM *tmp_e = NULL;
   for (key_prop = json->child; key_prop != NULL; key_prop = key_prop->next) {
     if (strcmp(key_prop->key, "n") == 0) {
-      rsa->n =
+      tmp_n =
           bignum_from_base64(exec_ctx, validate_string_field(key_prop, "n"));
-      if (rsa->n == NULL) goto end;
+      if (tmp_n == NULL) goto end;
     } else if (strcmp(key_prop->key, "e") == 0) {
-      rsa->e =
+      tmp_e =
           bignum_from_base64(exec_ctx, validate_string_field(key_prop, "e"));
-      if (rsa->e == NULL) goto end;
+      if (tmp_e == NULL) goto end;
     }
   }
-  if (rsa->e == NULL || rsa->n == NULL) {
+  if (tmp_e == NULL || tmp_n == NULL) {
     gpr_log(GPR_ERROR, "Missing RSA public key field.");
     goto end;
   }
+  if (!RSA_set0_key(rsa, tmp_n, tmp_e, NULL)) {
+    gpr_log(GPR_ERROR, "Cannot set RSA key from inputs.");
+    goto end;
+  }
   result = EVP_PKEY_new();
   EVP_PKEY_set1_RSA(result, rsa); /* uprefs rsa. */
 
@@ -683,7 +703,7 @@ static void on_openid_config_retrieved(grpc_exec_ctx *exec_ctx, void *user_data,
   grpc_httpcli_get(
       exec_ctx, &ctx->verifier->http_ctx, &ctx->pollent, resource_quota, &req,
       grpc_exec_ctx_now(exec_ctx) + grpc_jwt_verifier_max_delay,
-      grpc_closure_create(on_keys_retrieved, ctx, grpc_schedule_on_exec_ctx),
+      GRPC_CLOSURE_CREATE(on_keys_retrieved, ctx, grpc_schedule_on_exec_ctx),
       &ctx->responses[HTTP_RESPONSE_KEYS]);
   grpc_resource_quota_unref_internal(exec_ctx, resource_quota);
   grpc_json_destroy(json);
@@ -786,7 +806,7 @@ static void retrieve_key_and_verify(grpc_exec_ctx *exec_ctx,
       gpr_asprintf(&req.http.path, "/%s/%s", path_prefix, iss);
     }
     http_cb =
-        grpc_closure_create(on_keys_retrieved, ctx, grpc_schedule_on_exec_ctx);
+        GRPC_CLOSURE_CREATE(on_keys_retrieved, ctx, grpc_schedule_on_exec_ctx);
     rsp_idx = HTTP_RESPONSE_KEYS;
   } else {
     req.host = gpr_strdup(strstr(iss, "https://") == iss ? iss + 8 : iss);
@@ -798,7 +818,7 @@ static void retrieve_key_and_verify(grpc_exec_ctx *exec_ctx,
       gpr_asprintf(&req.http.path, "/%s%s", path_prefix,
                    GRPC_OPENID_CONFIG_URL_SUFFIX);
     }
-    http_cb = grpc_closure_create(on_openid_config_retrieved, ctx,
+    http_cb = GRPC_CLOSURE_CREATE(on_openid_config_retrieved, ctx,
                                   grpc_schedule_on_exec_ctx);
     rsp_idx = HTTP_RESPONSE_OPENID;
   }
diff --git a/src/core/lib/security/credentials/jwt/jwt_verifier.h b/src/core/lib/security/credentials/jwt/jwt_verifier.h
index 68fafce4c9..3a3261a780 100644
--- a/src/core/lib/security/credentials/jwt/jwt_verifier.h
+++ b/src/core/lib/security/credentials/jwt/jwt_verifier.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/security/credentials/oauth2/oauth2_credentials.c b/src/core/lib/security/credentials/oauth2/oauth2_credentials.c
index eaaf6367c3..f859535e89 100644
--- a/src/core/lib/security/credentials/oauth2/oauth2_credentials.c
+++ b/src/core/lib/security/credentials/oauth2/oauth2_credentials.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -311,7 +296,7 @@ static void compute_engine_fetch_oauth2(
       grpc_resource_quota_create("oauth2_credentials");
   grpc_httpcli_get(
       exec_ctx, httpcli_context, pollent, resource_quota, &request, deadline,
-      grpc_closure_create(response_cb, metadata_req, grpc_schedule_on_exec_ctx),
+      GRPC_CLOSURE_CREATE(response_cb, metadata_req, grpc_schedule_on_exec_ctx),
 
       &metadata_req->response);
   grpc_resource_quota_unref_internal(exec_ctx, resource_quota);
@@ -371,7 +356,7 @@ static void refresh_token_fetch_oauth2(
   grpc_httpcli_post(
       exec_ctx, httpcli_context, pollent, resource_quota, &request, body,
       strlen(body), deadline,
-      grpc_closure_create(response_cb, metadata_req, grpc_schedule_on_exec_ctx),
+      GRPC_CLOSURE_CREATE(response_cb, metadata_req, grpc_schedule_on_exec_ctx),
       &metadata_req->response);
   grpc_resource_quota_unref_internal(exec_ctx, resource_quota);
   gpr_free(body);
diff --git a/src/core/lib/security/credentials/oauth2/oauth2_credentials.h b/src/core/lib/security/credentials/oauth2/oauth2_credentials.h
index 88f5351f36..d5ada36368 100644
--- a/src/core/lib/security/credentials/oauth2/oauth2_credentials.h
+++ b/src/core/lib/security/credentials/oauth2/oauth2_credentials.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/security/credentials/plugin/plugin_credentials.c b/src/core/lib/security/credentials/plugin/plugin_credentials.c
index 8416bfa5a8..96ebfb4d0d 100644
--- a/src/core/lib/security/credentials/plugin/plugin_credentials.c
+++ b/src/core/lib/security/credentials/plugin/plugin_credentials.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/security/credentials/plugin/plugin_credentials.h b/src/core/lib/security/credentials/plugin/plugin_credentials.h
index 89073cb3d1..ba3dd76859 100644
--- a/src/core/lib/security/credentials/plugin/plugin_credentials.h
+++ b/src/core/lib/security/credentials/plugin/plugin_credentials.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/security/credentials/ssl/ssl_credentials.c b/src/core/lib/security/credentials/ssl/ssl_credentials.c
index 7c35ebe684..006db1ec76 100644
--- a/src/core/lib/security/credentials/ssl/ssl_credentials.c
+++ b/src/core/lib/security/credentials/ssl/ssl_credentials.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -67,11 +52,8 @@ static grpc_security_status ssl_create_security_connector(
     grpc_channel_args **new_args) {
   grpc_ssl_credentials *c = (grpc_ssl_credentials *)creds;
   grpc_security_status status = GRPC_SECURITY_OK;
-  size_t i = 0;
   const char *overridden_target_name = NULL;
-  grpc_arg new_arg;
-
-  for (i = 0; args && i < args->num_args; i++) {
+  for (size_t i = 0; args && i < args->num_args; i++) {
     grpc_arg *arg = &args->args[i];
     if (strcmp(arg->key, GRPC_SSL_TARGET_NAME_OVERRIDE_ARG) == 0 &&
         arg->type == GRPC_ARG_STRING) {
@@ -84,9 +66,8 @@ static grpc_security_status ssl_create_security_connector(
   if (status != GRPC_SECURITY_OK) {
     return status;
   }
-  new_arg.type = GRPC_ARG_STRING;
-  new_arg.key = GRPC_ARG_HTTP2_SCHEME;
-  new_arg.value.string = "https";
+  grpc_arg new_arg =
+      grpc_channel_arg_string_create(GRPC_ARG_HTTP2_SCHEME, "https");
   *new_args = grpc_channel_args_copy_and_add(args, &new_arg, 1);
   return status;
 }
diff --git a/src/core/lib/security/credentials/ssl/ssl_credentials.h b/src/core/lib/security/credentials/ssl/ssl_credentials.h
index f23dbdbe49..b43c656cd7 100644
--- a/src/core/lib/security/credentials/ssl/ssl_credentials.h
+++ b/src/core/lib/security/credentials/ssl/ssl_credentials.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 #ifndef GRPC_CORE_LIB_SECURITY_CREDENTIALS_SSL_SSL_CREDENTIALS_H
diff --git a/src/core/lib/security/transport/auth_filters.h b/src/core/lib/security/transport/auth_filters.h
index f688d4ed21..bd5902a128 100644
--- a/src/core/lib/security/transport/auth_filters.h
+++ b/src/core/lib/security/transport/auth_filters.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/security/transport/client_auth_filter.c b/src/core/lib/security/transport/client_auth_filter.c
index dff05633ec..50a51b31cd 100644
--- a/src/core/lib/security/transport/client_auth_filter.c
+++ b/src/core/lib/security/transport/client_auth_filter.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -64,8 +49,8 @@ typedef struct {
      pollset_set so that work can progress when this call wants work to progress
   */
   grpc_polling_entity *pollent;
-  grpc_transport_stream_op_batch op;
-  uint8_t security_context_set;
+  gpr_atm security_context_set;
+  gpr_mu security_context_mu;
   grpc_linked_mdelem md_links[MAX_CREDENTIALS_METADATA_COUNT];
   grpc_auth_metadata_context auth_md_context;
 } call_data;
@@ -106,11 +91,10 @@ static void on_credentials_metadata(grpc_exec_ctx *exec_ctx, void *user_data,
                                     size_t num_md,
                                     grpc_credentials_status status,
                                     const char *error_details) {
-  grpc_call_element *elem = (grpc_call_element *)user_data;
+  grpc_transport_stream_op_batch *batch =
+      (grpc_transport_stream_op_batch *)user_data;
+  grpc_call_element *elem = batch->handler_private.extra_arg;
   call_data *calld = elem->call_data;
-  grpc_transport_stream_op_batch *op = &calld->op;
-  grpc_metadata_batch *mdb;
-  size_t i;
   reset_auth_metadata_context(&calld->auth_md_context);
   grpc_error *error = GRPC_ERROR_NONE;
   if (status != GRPC_CREDENTIALS_OK) {
@@ -122,9 +106,10 @@ static void on_credentials_metadata(grpc_exec_ctx *exec_ctx, void *user_data,
         GRPC_ERROR_INT_GRPC_STATUS, GRPC_STATUS_UNAUTHENTICATED);
   } else {
     GPR_ASSERT(num_md <= MAX_CREDENTIALS_METADATA_COUNT);
-    GPR_ASSERT(op->send_initial_metadata);
-    mdb = op->payload->send_initial_metadata.send_initial_metadata;
-    for (i = 0; i < num_md; i++) {
+    GPR_ASSERT(batch->send_initial_metadata);
+    grpc_metadata_batch *mdb =
+        batch->payload->send_initial_metadata.send_initial_metadata;
+    for (size_t i = 0; i < num_md; i++) {
       add_error(&error,
                 grpc_metadata_batch_add_tail(
                     exec_ctx, mdb, &calld->md_links[i],
@@ -134,9 +119,9 @@ static void on_credentials_metadata(grpc_exec_ctx *exec_ctx, void *user_data,
     }
   }
   if (error == GRPC_ERROR_NONE) {
-    grpc_call_next_op(exec_ctx, elem, op);
+    grpc_call_next_op(exec_ctx, elem, batch);
   } else {
-    grpc_transport_stream_op_batch_finish_with_failure(exec_ctx, op, error);
+    grpc_transport_stream_op_batch_finish_with_failure(exec_ctx, batch, error);
   }
 }
 
@@ -172,11 +157,11 @@ void build_auth_metadata_context(grpc_security_connector *sc,
 
 static void send_security_metadata(grpc_exec_ctx *exec_ctx,
                                    grpc_call_element *elem,
-                                   grpc_transport_stream_op_batch *op) {
+                                   grpc_transport_stream_op_batch *batch) {
   call_data *calld = elem->call_data;
   channel_data *chand = elem->channel_data;
   grpc_client_security_context *ctx =
-      (grpc_client_security_context *)op->payload
+      (grpc_client_security_context *)batch->payload
           ->context[GRPC_CONTEXT_SECURITY]
           .value;
   grpc_call_credentials *channel_call_creds =
@@ -185,7 +170,7 @@ static void send_security_metadata(grpc_exec_ctx *exec_ctx,
 
   if (channel_call_creds == NULL && !call_creds_has_md) {
     /* Skip sending metadata altogether. */
-    grpc_call_next_op(exec_ctx, elem, op);
+    grpc_call_next_op(exec_ctx, elem, batch);
     return;
   }
 
@@ -194,7 +179,7 @@ static void send_security_metadata(grpc_exec_ctx *exec_ctx,
                                                           ctx->creds, NULL);
     if (calld->creds == NULL) {
       grpc_transport_stream_op_batch_finish_with_failure(
-          exec_ctx, op,
+          exec_ctx, batch,
           grpc_error_set_int(
               GRPC_ERROR_CREATE_FROM_STATIC_STRING(
                   "Incompatible credentials set on channel and call."),
@@ -208,28 +193,29 @@ static void send_security_metadata(grpc_exec_ctx *exec_ctx,
 
   build_auth_metadata_context(&chand->security_connector->base,
                               chand->auth_context, calld);
-  calld->op = *op; /* Copy op (originates from the caller's stack). */
   GPR_ASSERT(calld->pollent != NULL);
   grpc_call_credentials_get_request_metadata(
       exec_ctx, calld->creds, calld->pollent, calld->auth_md_context,
-      on_credentials_metadata, elem);
+      on_credentials_metadata, batch);
 }
 
 static void on_host_checked(grpc_exec_ctx *exec_ctx, void *user_data,
                             grpc_security_status status) {
-  grpc_call_element *elem = (grpc_call_element *)user_data;
+  grpc_transport_stream_op_batch *batch =
+      (grpc_transport_stream_op_batch *)user_data;
+  grpc_call_element *elem = batch->handler_private.extra_arg;
   call_data *calld = elem->call_data;
 
   if (status == GRPC_SECURITY_OK) {
-    send_security_metadata(exec_ctx, elem, &calld->op);
+    send_security_metadata(exec_ctx, elem, batch);
   } else {
     char *error_msg;
     char *host = grpc_slice_to_c_string(calld->host);
     gpr_asprintf(&error_msg, "Invalid host %s set in :authority metadata.",
                  host);
     gpr_free(host);
-    grpc_call_element_signal_error(
-        exec_ctx, elem,
+    grpc_transport_stream_op_batch_finish_with_failure(
+        exec_ctx, batch,
         grpc_error_set_int(GRPC_ERROR_CREATE_FROM_COPIED_STRING(error_msg),
                            GRPC_ERROR_INT_GRPC_STATUS,
                            GRPC_STATUS_UNAUTHENTICATED));
@@ -237,40 +223,41 @@ static void on_host_checked(grpc_exec_ctx *exec_ctx, void *user_data,
   }
 }
 
-/* Called either:
-     - in response to an API call (or similar) from above, to send something
-     - a network event (or similar) from below, to receive something
-   op contains type and call direction information, in addition to the data
-   that is being sent or received. */
-static void auth_start_transport_op(grpc_exec_ctx *exec_ctx,
-                                    grpc_call_element *elem,
-                                    grpc_transport_stream_op_batch *op) {
-  GPR_TIMER_BEGIN("auth_start_transport_op", 0);
+static void auth_start_transport_stream_op_batch(
+    grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
+    grpc_transport_stream_op_batch *batch) {
+  GPR_TIMER_BEGIN("auth_start_transport_stream_op_batch", 0);
 
   /* grab pointers to our data from the call element */
   call_data *calld = elem->call_data;
   channel_data *chand = elem->channel_data;
-  grpc_linked_mdelem *l;
-  grpc_client_security_context *sec_ctx = NULL;
 
-  if (!op->cancel_stream && calld->security_context_set == 0) {
-    calld->security_context_set = 1;
-    GPR_ASSERT(op->payload->context != NULL);
-    if (op->payload->context[GRPC_CONTEXT_SECURITY].value == NULL) {
-      op->payload->context[GRPC_CONTEXT_SECURITY].value =
-          grpc_client_security_context_create();
-      op->payload->context[GRPC_CONTEXT_SECURITY].destroy =
-          grpc_client_security_context_destroy;
+  if (!batch->cancel_stream) {
+    /* double checked lock over security context to ensure it's set once */
+    if (gpr_atm_acq_load(&calld->security_context_set) == 0) {
+      gpr_mu_lock(&calld->security_context_mu);
+      if (gpr_atm_acq_load(&calld->security_context_set) == 0) {
+        GPR_ASSERT(batch->payload->context != NULL);
+        if (batch->payload->context[GRPC_CONTEXT_SECURITY].value == NULL) {
+          batch->payload->context[GRPC_CONTEXT_SECURITY].value =
+              grpc_client_security_context_create();
+          batch->payload->context[GRPC_CONTEXT_SECURITY].destroy =
+              grpc_client_security_context_destroy;
+        }
+        grpc_client_security_context *sec_ctx =
+            batch->payload->context[GRPC_CONTEXT_SECURITY].value;
+        GRPC_AUTH_CONTEXT_UNREF(sec_ctx->auth_context, "client auth filter");
+        sec_ctx->auth_context =
+            GRPC_AUTH_CONTEXT_REF(chand->auth_context, "client_auth_filter");
+        gpr_atm_rel_store(&calld->security_context_set, 1);
+      }
+      gpr_mu_unlock(&calld->security_context_mu);
     }
-    sec_ctx = op->payload->context[GRPC_CONTEXT_SECURITY].value;
-    GRPC_AUTH_CONTEXT_UNREF(sec_ctx->auth_context, "client auth filter");
-    sec_ctx->auth_context =
-        GRPC_AUTH_CONTEXT_REF(chand->auth_context, "client_auth_filter");
   }
 
-  if (op->send_initial_metadata) {
-    for (l = op->payload->send_initial_metadata.send_initial_metadata->list
-                 .head;
+  if (batch->send_initial_metadata) {
+    for (grpc_linked_mdelem *l = batch->payload->send_initial_metadata
+                                     .send_initial_metadata->list.head;
          l != NULL; l = l->next) {
       grpc_mdelem md = l->md;
       /* Pointer comparison is OK for md_elems created from the same context.
@@ -291,19 +278,19 @@ static void auth_start_transport_op(grpc_exec_ctx *exec_ctx,
     }
     if (calld->have_host) {
       char *call_host = grpc_slice_to_c_string(calld->host);
-      calld->op = *op; /* Copy op (originates from the caller's stack). */
+      batch->handler_private.extra_arg = elem;
       grpc_channel_security_connector_check_call_host(
           exec_ctx, chand->security_connector, call_host, chand->auth_context,
-          on_host_checked, elem);
+          on_host_checked, batch);
       gpr_free(call_host);
-      GPR_TIMER_END("auth_start_transport_op", 0);
+      GPR_TIMER_END("auth_start_transport_stream_op_batch", 0);
       return; /* early exit */
     }
   }
 
   /* pass control down the stack */
-  grpc_call_next_op(exec_ctx, elem, op);
-  GPR_TIMER_END("auth_start_transport_op", 0);
+  grpc_call_next_op(exec_ctx, elem, batch);
+  GPR_TIMER_END("auth_start_transport_stream_op_batch", 0);
 }
 
 /* Constructor for call_data */
@@ -312,6 +299,7 @@ static grpc_error *init_call_elem(grpc_exec_ctx *exec_ctx,
                                   const grpc_call_element_args *args) {
   call_data *calld = elem->call_data;
   memset(calld, 0, sizeof(*calld));
+  gpr_mu_init(&calld->security_context_mu);
   return GRPC_ERROR_NONE;
 }
 
@@ -335,6 +323,7 @@ static void destroy_call_elem(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
     grpc_slice_unref_internal(exec_ctx, calld->method);
   }
   reset_auth_metadata_context(&calld->auth_md_context);
+  gpr_mu_destroy(&calld->security_context_mu);
 }
 
 /* Constructor for channel_data */
@@ -384,7 +373,15 @@ static void destroy_channel_elem(grpc_exec_ctx *exec_ctx,
 }
 
 const grpc_channel_filter grpc_client_auth_filter = {
-    auth_start_transport_op, grpc_channel_next_op,       sizeof(call_data),
-    init_call_elem,          set_pollset_or_pollset_set, destroy_call_elem,
-    sizeof(channel_data),    init_channel_elem,          destroy_channel_elem,
-    grpc_call_next_get_peer, grpc_channel_next_get_info, "client-auth"};
+    auth_start_transport_stream_op_batch,
+    grpc_channel_next_op,
+    sizeof(call_data),
+    init_call_elem,
+    set_pollset_or_pollset_set,
+    destroy_call_elem,
+    sizeof(channel_data),
+    init_channel_elem,
+    destroy_channel_elem,
+    grpc_call_next_get_peer,
+    grpc_channel_next_get_info,
+    "client-auth"};
diff --git a/src/core/lib/security/transport/lb_targets_info.c b/src/core/lib/security/transport/lb_targets_info.c
index e73483c039..5583a4e0ff 100644
--- a/src/core/lib/security/transport/lb_targets_info.c
+++ b/src/core/lib/security/transport/lb_targets_info.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2017, Google Inc.
- * All rights reserved.
+ * Copyright 2017 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -44,18 +29,17 @@ static void *targets_info_copy(void *p) { return grpc_slice_hash_table_ref(p); }
 static void targets_info_destroy(grpc_exec_ctx *exec_ctx, void *p) {
   grpc_slice_hash_table_unref(exec_ctx, p);
 }
-static int targets_info_cmp(void *a, void *b) { return GPR_ICMP(a, b); }
+static int targets_info_cmp(void *a, void *b) {
+  return grpc_slice_hash_table_cmp(a, b);
+}
 static const grpc_arg_pointer_vtable server_to_balancer_names_vtable = {
     targets_info_copy, targets_info_destroy, targets_info_cmp};
 
 grpc_arg grpc_lb_targets_info_create_channel_arg(
     grpc_slice_hash_table *targets_info) {
-  grpc_arg arg;
-  arg.type = GRPC_ARG_POINTER;
-  arg.key = GRPC_ARG_LB_SECURE_NAMING_MAP;
-  arg.value.pointer.p = targets_info;
-  arg.value.pointer.vtable = &server_to_balancer_names_vtable;
-  return arg;
+  return grpc_channel_arg_pointer_create(GRPC_ARG_LB_SECURE_NAMING_MAP,
+                                         targets_info,
+                                         &server_to_balancer_names_vtable);
 }
 
 grpc_slice_hash_table *grpc_lb_targets_info_find_in_args(
diff --git a/src/core/lib/security/transport/lb_targets_info.h b/src/core/lib/security/transport/lb_targets_info.h
index 5e6cacc197..c3d685df5f 100644
--- a/src/core/lib/security/transport/lb_targets_info.h
+++ b/src/core/lib/security/transport/lb_targets_info.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2017, Google Inc.
- * All rights reserved.
+ * Copyright 2017 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/security/transport/secure_endpoint.c b/src/core/lib/security/transport/secure_endpoint.c
index 48d368a2a7..5e41b94ff8 100644
--- a/src/core/lib/security/transport/secure_endpoint.c
+++ b/src/core/lib/security/transport/secure_endpoint.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -75,7 +60,8 @@ typedef struct {
   gpr_refcount ref;
 } secure_endpoint;
 
-grpc_tracer_flag grpc_trace_secure_endpoint = GRPC_TRACER_INITIALIZER(false);
+grpc_tracer_flag grpc_trace_secure_endpoint =
+    GRPC_TRACER_INITIALIZER(false, "secure_endpoint");
 
 static void destroy(grpc_exec_ctx *exec_ctx, secure_endpoint *secure_ep) {
   secure_endpoint *ep = secure_ep;
@@ -90,18 +76,20 @@ static void destroy(grpc_exec_ctx *exec_ctx, secure_endpoint *secure_ep) {
   gpr_free(ep);
 }
 
-/*#define GRPC_SECURE_ENDPOINT_REFCOUNT_DEBUG*/
-#ifdef GRPC_SECURE_ENDPOINT_REFCOUNT_DEBUG
+#ifndef NDEBUG
 #define SECURE_ENDPOINT_UNREF(exec_ctx, ep, reason) \
   secure_endpoint_unref((exec_ctx), (ep), (reason), __FILE__, __LINE__)
 #define SECURE_ENDPOINT_REF(ep, reason) \
   secure_endpoint_ref((ep), (reason), __FILE__, __LINE__)
-static void secure_endpoint_unref(secure_endpoint *ep,
-                                  grpc_closure_list *closure_list,
+static void secure_endpoint_unref(grpc_exec_ctx *exec_ctx, secure_endpoint *ep,
                                   const char *reason, const char *file,
                                   int line) {
-  gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG, "SECENDP unref %p : %s %d -> %d",
-          ep, reason, ep->ref.count, ep->ref.count - 1);
+  if (GRPC_TRACER_ON(grpc_trace_secure_endpoint)) {
+    gpr_atm val = gpr_atm_no_barrier_load(&ep->ref.count);
+    gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
+            "SECENDP unref %p : %s %" PRIdPTR " -> %" PRIdPTR, ep, reason, val,
+            val - 1);
+  }
   if (gpr_unref(&ep->ref)) {
     destroy(exec_ctx, ep);
   }
@@ -109,8 +97,12 @@ static void secure_endpoint_unref(secure_endpoint *ep,
 
 static void secure_endpoint_ref(secure_endpoint *ep, const char *reason,
                                 const char *file, int line) {
-  gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG, "SECENDP   ref %p : %s %d -> %d",
-          ep, reason, ep->ref.count, ep->ref.count + 1);
+  if (GRPC_TRACER_ON(grpc_trace_secure_endpoint)) {
+    gpr_atm val = gpr_atm_no_barrier_load(&ep->ref.count);
+    gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
+            "SECENDP   ref %p : %s %" PRIdPTR " -> %" PRIdPTR, ep, reason, val,
+            val + 1);
+  }
   gpr_ref(&ep->ref);
 }
 #else
@@ -147,7 +139,7 @@ static void call_read_cb(grpc_exec_ctx *exec_ctx, secure_endpoint *ep,
     }
   }
   ep->read_buffer = NULL;
-  grpc_closure_sched(exec_ctx, ep->read_cb, error);
+  GRPC_CLOSURE_SCHED(exec_ctx, ep->read_cb, error);
   SECURE_ENDPOINT_UNREF(exec_ctx, ep, "read");
 }
 
@@ -332,7 +324,7 @@ static void endpoint_write(grpc_exec_ctx *exec_ctx, grpc_endpoint *secure_ep,
   if (result != TSI_OK) {
     /* TODO(yangg) do different things according to the error type? */
     grpc_slice_buffer_reset_and_unref_internal(exec_ctx, &ep->output_buffer);
-    grpc_closure_sched(
+    GRPC_CLOSURE_SCHED(
         exec_ctx, cb,
         grpc_set_tsi_error_result(
             GRPC_ERROR_CREATE_FROM_STATIC_STRING("Wrap failed"), result));
@@ -380,11 +372,6 @@ static int endpoint_get_fd(grpc_endpoint *secure_ep) {
   return grpc_endpoint_get_fd(ep->wrapped_ep);
 }
 
-static grpc_workqueue *endpoint_get_workqueue(grpc_endpoint *secure_ep) {
-  secure_endpoint *ep = (secure_endpoint *)secure_ep;
-  return grpc_endpoint_get_workqueue(ep->wrapped_ep);
-}
-
 static grpc_resource_user *endpoint_get_resource_user(
     grpc_endpoint *secure_ep) {
   secure_endpoint *ep = (secure_endpoint *)secure_ep;
@@ -393,7 +380,6 @@ static grpc_resource_user *endpoint_get_resource_user(
 
 static const grpc_endpoint_vtable vtable = {endpoint_read,
                                             endpoint_write,
-                                            endpoint_get_workqueue,
                                             endpoint_add_to_pollset,
                                             endpoint_add_to_pollset_set,
                                             endpoint_shutdown,
@@ -420,7 +406,7 @@ grpc_endpoint *grpc_secure_endpoint_create(
   grpc_slice_buffer_init(&ep->output_buffer);
   grpc_slice_buffer_init(&ep->source_buffer);
   ep->read_buffer = NULL;
-  grpc_closure_init(&ep->on_read, on_read, ep, grpc_schedule_on_exec_ctx);
+  GRPC_CLOSURE_INIT(&ep->on_read, on_read, ep, grpc_schedule_on_exec_ctx);
   gpr_mu_init(&ep->protector_mu);
   gpr_ref_init(&ep->ref, 1);
   return &ep->base;
diff --git a/src/core/lib/security/transport/secure_endpoint.h b/src/core/lib/security/transport/secure_endpoint.h
index f1a5c8cb6d..1c5555f3df 100644
--- a/src/core/lib/security/transport/secure_endpoint.h
+++ b/src/core/lib/security/transport/secure_endpoint.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/security/transport/security_connector.c b/src/core/lib/security/transport/security_connector.c
index 30431a4e4a..6788126769 100644
--- a/src/core/lib/security/transport/security_connector.c
+++ b/src/core/lib/security/transport/security_connector.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -56,6 +41,12 @@
 #include "src/core/lib/support/string.h"
 #include "src/core/tsi/fake_transport_security.h"
 #include "src/core/tsi/ssl_transport_security.h"
+#include "src/core/tsi/transport_security_adapter.h"
+
+#ifndef NDEBUG
+grpc_tracer_flag grpc_trace_security_connector_refcount =
+    GRPC_TRACER_INITIALIZER(false, "security_connector_refcount");
+#endif
 
 /* -- Constants. -- */
 
@@ -136,7 +127,7 @@ void grpc_security_connector_check_peer(grpc_exec_ctx *exec_ctx,
                                         grpc_auth_context **auth_context,
                                         grpc_closure *on_peer_checked) {
   if (sc == NULL) {
-    grpc_closure_sched(exec_ctx, on_peer_checked,
+    GRPC_CLOSURE_SCHED(exec_ctx, on_peer_checked,
                        GRPC_ERROR_CREATE_FROM_STATIC_STRING(
                            "cannot check peer -- no security connector"));
     tsi_peer_destruct(&peer);
@@ -156,14 +147,17 @@ void grpc_channel_security_connector_check_call_host(
   }
 }
 
-#ifdef GRPC_SECURITY_CONNECTOR_REFCOUNT_DEBUG
+#ifndef NDEBUG
 grpc_security_connector *grpc_security_connector_ref(
     grpc_security_connector *sc, const char *file, int line,
     const char *reason) {
   if (sc == NULL) return NULL;
-  gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
-          "SECURITY_CONNECTOR:%p   ref %d -> %d %s", sc,
-          (int)sc->refcount.count, (int)sc->refcount.count + 1, reason);
+  if (GRPC_TRACER_ON(grpc_trace_security_connector_refcount)) {
+    gpr_atm val = gpr_atm_no_barrier_load(&sc->refcount.count);
+    gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
+            "SECURITY_CONNECTOR:%p   ref %" PRIdPTR " -> %" PRIdPTR " %s", sc,
+            val, val + 1, reason);
+  }
 #else
 grpc_security_connector *grpc_security_connector_ref(
     grpc_security_connector *sc) {
@@ -173,15 +167,18 @@ grpc_security_connector *grpc_security_connector_ref(
   return sc;
 }
 
-#ifdef GRPC_SECURITY_CONNECTOR_REFCOUNT_DEBUG
+#ifndef NDEBUG
 void grpc_security_connector_unref(grpc_exec_ctx *exec_ctx,
                                    grpc_security_connector *sc,
                                    const char *file, int line,
                                    const char *reason) {
   if (sc == NULL) return;
-  gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
-          "SECURITY_CONNECTOR:%p unref %d -> %d %s", sc,
-          (int)sc->refcount.count, (int)sc->refcount.count - 1, reason);
+  if (GRPC_TRACER_ON(grpc_trace_security_connector_refcount)) {
+    gpr_atm val = gpr_atm_no_barrier_load(&sc->refcount.count);
+    gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
+            "SECURITY_CONNECTOR:%p unref %" PRIdPTR " -> %" PRIdPTR " %s", sc,
+            val, val - 1, reason);
+  }
 #else
 void grpc_security_connector_unref(grpc_exec_ctx *exec_ctx,
                                    grpc_security_connector *sc) {
@@ -205,12 +202,8 @@ static const grpc_arg_pointer_vtable connector_pointer_vtable = {
     connector_pointer_cmp};
 
 grpc_arg grpc_security_connector_to_arg(grpc_security_connector *sc) {
-  grpc_arg result;
-  result.type = GRPC_ARG_POINTER;
-  result.key = GRPC_ARG_SECURITY_CONNECTOR;
-  result.value.pointer.vtable = &connector_pointer_vtable;
-  result.value.pointer.p = sc;
-  return result;
+  return grpc_channel_arg_pointer_create(GRPC_ARG_SECURITY_CONNECTOR, sc,
+                                         &connector_pointer_vtable);
 }
 
 grpc_security_connector *grpc_security_connector_from_arg(const grpc_arg *arg) {
@@ -354,7 +347,7 @@ static void fake_check_peer(grpc_exec_ctx *exec_ctx,
       *auth_context, GRPC_TRANSPORT_SECURITY_TYPE_PROPERTY_NAME,
       GRPC_FAKE_TRANSPORT_SECURITY_TYPE);
 end:
-  grpc_closure_sched(exec_ctx, on_peer_checked, error);
+  GRPC_CLOSURE_SCHED(exec_ctx, on_peer_checked, error);
   tsi_peer_destruct(&peer);
 }
 
@@ -495,8 +488,10 @@ static void ssl_channel_add_handshakers(grpc_exec_ctx *exec_ctx,
   }
 
   // Create handshakers.
-  grpc_handshake_manager_add(handshake_mgr, grpc_security_handshaker_create(
-                                                exec_ctx, tsi_hs, &sc->base));
+  grpc_handshake_manager_add(
+      handshake_mgr,
+      grpc_security_handshaker_create(
+          exec_ctx, tsi_create_adapter_handshaker(tsi_hs), &sc->base));
 }
 
 static void ssl_server_add_handshakers(grpc_exec_ctx *exec_ctx,
@@ -515,8 +510,10 @@ static void ssl_server_add_handshakers(grpc_exec_ctx *exec_ctx,
   }
 
   // Create handshakers.
-  grpc_handshake_manager_add(handshake_mgr, grpc_security_handshaker_create(
-                                                exec_ctx, tsi_hs, &sc->base));
+  grpc_handshake_manager_add(
+      handshake_mgr,
+      grpc_security_handshaker_create(
+          exec_ctx, tsi_create_adapter_handshaker(tsi_hs), &sc->base));
 }
 
 static int ssl_host_matches_name(const tsi_peer *peer, const char *peer_name) {
@@ -610,7 +607,7 @@ static void ssl_channel_check_peer(grpc_exec_ctx *exec_ctx,
                                              ? c->overridden_target_name
                                              : c->target_name,
                                      &peer, auth_context);
-  grpc_closure_sched(exec_ctx, on_peer_checked, error);
+  GRPC_CLOSURE_SCHED(exec_ctx, on_peer_checked, error);
   tsi_peer_destruct(&peer);
 }
 
@@ -620,7 +617,7 @@ static void ssl_server_check_peer(grpc_exec_ctx *exec_ctx,
                                   grpc_closure *on_peer_checked) {
   grpc_error *error = ssl_check_peer(sc, NULL, &peer, auth_context);
   tsi_peer_destruct(&peer);
-  grpc_closure_sched(exec_ctx, on_peer_checked, error);
+  GRPC_CLOSURE_SCHED(exec_ctx, on_peer_checked, error);
 }
 
 static void add_shallow_auth_property_to_peer(tsi_peer *peer,
diff --git a/src/core/lib/security/transport/security_connector.h b/src/core/lib/security/transport/security_connector.h
index d74f6739c0..1c0fe40045 100644
--- a/src/core/lib/security/transport/security_connector.h
+++ b/src/core/lib/security/transport/security_connector.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -44,6 +29,10 @@
 #include "src/core/tsi/ssl_transport_security.h"
 #include "src/core/tsi/transport_security_interface.h"
 
+#ifndef NDEBUG
+extern grpc_tracer_flag grpc_trace_security_connector_refcount;
+#endif
+
 /* --- status enum. --- */
 
 typedef enum { GRPC_SECURITY_OK = 0, GRPC_SECURITY_ERROR } grpc_security_status;
@@ -81,7 +70,7 @@ struct grpc_security_connector {
 };
 
 /* Refcounting. */
-#ifdef GRPC_SECURITY_CONNECTOR_REFCOUNT_DEBUG
+#ifndef NDEBUG
 #define GRPC_SECURITY_CONNECTOR_REF(p, r) \
   grpc_security_connector_ref((p), __FILE__, __LINE__, (r))
 #define GRPC_SECURITY_CONNECTOR_UNREF(exec_ctx, p, r) \
diff --git a/src/core/lib/security/transport/security_handshaker.c b/src/core/lib/security/transport/security_handshaker.c
index 509b4b556d..239a211c0b 100644
--- a/src/core/lib/security/transport/security_handshaker.c
+++ b/src/core/lib/security/transport/security_handshaker.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -71,12 +56,12 @@ typedef struct {
 
   unsigned char *handshake_buffer;
   size_t handshake_buffer_size;
-  grpc_slice_buffer left_overs;
   grpc_slice_buffer outgoing;
   grpc_closure on_handshake_data_sent_to_peer;
   grpc_closure on_handshake_data_received_from_peer;
   grpc_closure on_peer_checked;
   grpc_auth_context *auth_context;
+  tsi_handshaker_result *handshaker_result;
 } security_handshaker;
 
 static void security_handshaker_unref(grpc_exec_ctx *exec_ctx,
@@ -84,6 +69,7 @@ static void security_handshaker_unref(grpc_exec_ctx *exec_ctx,
   if (gpr_unref(&h->refs)) {
     gpr_mu_destroy(&h->mu);
     tsi_handshaker_destroy(h->handshaker);
+    tsi_handshaker_result_destroy(h->handshaker_result);
     if (h->endpoint_to_destroy != NULL) {
       grpc_endpoint_destroy(exec_ctx, h->endpoint_to_destroy);
     }
@@ -92,7 +78,6 @@ static void security_handshaker_unref(grpc_exec_ctx *exec_ctx,
       gpr_free(h->read_buffer_to_destroy);
     }
     gpr_free(h->handshake_buffer);
-    grpc_slice_buffer_destroy_internal(exec_ctx, &h->left_overs);
     grpc_slice_buffer_destroy_internal(exec_ctx, &h->outgoing);
     GRPC_AUTH_CONTEXT_UNREF(h->auth_context, "handshake");
     GRPC_SECURITY_CONNECTOR_UNREF(exec_ctx, h->connector, "handshake");
@@ -139,7 +124,7 @@ static void security_handshake_failed_locked(grpc_exec_ctx *exec_ctx,
     h->shutdown = true;
   }
   // Invoke callback.
-  grpc_closure_sched(exec_ctx, h->on_handshake_done, error);
+  GRPC_CLOSURE_SCHED(exec_ctx, h->on_handshake_done, error);
 }
 
 static void on_peer_checked(grpc_exec_ctx *exec_ctx, void *arg,
@@ -150,10 +135,10 @@ static void on_peer_checked(grpc_exec_ctx *exec_ctx, void *arg,
     security_handshake_failed_locked(exec_ctx, h, GRPC_ERROR_REF(error));
     goto done;
   }
-  // Get frame protector.
+  // Create frame protector.
   tsi_frame_protector *protector;
-  tsi_result result =
-      tsi_handshaker_create_frame_protector(h->handshaker, NULL, &protector);
+  tsi_result result = tsi_handshaker_result_create_frame_protector(
+      h->handshaker_result, NULL, &protector);
   if (result != TSI_OK) {
     error = grpc_set_tsi_error_result(
         GRPC_ERROR_CREATE_FROM_STATIC_STRING("Frame protector creation failed"),
@@ -161,14 +146,25 @@ static void on_peer_checked(grpc_exec_ctx *exec_ctx, void *arg,
     security_handshake_failed_locked(exec_ctx, h, error);
     goto done;
   }
-  // Success.
+  // Get unused bytes.
+  unsigned char *unused_bytes = NULL;
+  size_t unused_bytes_size = 0;
+  result = tsi_handshaker_result_get_unused_bytes(
+      h->handshaker_result, &unused_bytes, &unused_bytes_size);
   // Create secure endpoint.
-  h->args->endpoint = grpc_secure_endpoint_create(
-      protector, h->args->endpoint, h->left_overs.slices, h->left_overs.count);
-  h->left_overs.count = 0;
-  h->left_overs.length = 0;
-  // Clear out the read buffer before it gets passed to the transport,
-  // since any excess bytes were already copied to h->left_overs.
+  if (unused_bytes_size > 0) {
+    grpc_slice slice =
+        grpc_slice_from_copied_buffer((char *)unused_bytes, unused_bytes_size);
+    h->args->endpoint =
+        grpc_secure_endpoint_create(protector, h->args->endpoint, &slice, 1);
+    grpc_slice_unref_internal(exec_ctx, slice);
+  } else {
+    h->args->endpoint =
+        grpc_secure_endpoint_create(protector, h->args->endpoint, NULL, 0);
+  }
+  tsi_handshaker_result_destroy(h->handshaker_result);
+  h->handshaker_result = NULL;
+  // Clear out the read buffer before it gets passed to the transport.
   grpc_slice_buffer_reset_and_unref_internal(exec_ctx, h->args->read_buffer);
   // Add auth context to channel args.
   grpc_arg auth_context_arg = grpc_auth_context_to_arg(h->auth_context);
@@ -177,7 +173,7 @@ static void on_peer_checked(grpc_exec_ctx *exec_ctx, void *arg,
       grpc_channel_args_copy_and_add(tmp_args, &auth_context_arg, 1);
   grpc_channel_args_destroy(exec_ctx, tmp_args);
   // Invoke callback.
-  grpc_closure_sched(exec_ctx, h->on_handshake_done, GRPC_ERROR_NONE);
+  GRPC_CLOSURE_SCHED(exec_ctx, h->on_handshake_done, GRPC_ERROR_NONE);
   // Set shutdown to true so that subsequent calls to
   // security_handshaker_shutdown() do nothing.
   h->shutdown = true;
@@ -189,7 +185,8 @@ done:
 static grpc_error *check_peer_locked(grpc_exec_ctx *exec_ctx,
                                      security_handshaker *h) {
   tsi_peer peer;
-  tsi_result result = tsi_handshaker_extract_peer(h->handshaker, &peer);
+  tsi_result result =
+      tsi_handshaker_result_extract_peer(h->handshaker_result, &peer);
   if (result != TSI_OK) {
     return grpc_set_tsi_error_result(
         GRPC_ERROR_CREATE_FROM_STATIC_STRING("Peer extraction failed"), result);
@@ -199,34 +196,87 @@ static grpc_error *check_peer_locked(grpc_exec_ctx *exec_ctx,
   return GRPC_ERROR_NONE;
 }
 
-static grpc_error *send_handshake_bytes_to_peer_locked(grpc_exec_ctx *exec_ctx,
-                                                       security_handshaker *h) {
-  // Get data to send.
-  tsi_result result = TSI_OK;
-  size_t offset = 0;
-  do {
-    size_t to_send_size = h->handshake_buffer_size - offset;
-    result = tsi_handshaker_get_bytes_to_send_to_peer(
-        h->handshaker, h->handshake_buffer + offset, &to_send_size);
-    offset += to_send_size;
-    if (result == TSI_INCOMPLETE_DATA) {
-      h->handshake_buffer_size *= 2;
-      h->handshake_buffer =
-          gpr_realloc(h->handshake_buffer, h->handshake_buffer_size);
-    }
-  } while (result == TSI_INCOMPLETE_DATA);
+static grpc_error *on_handshake_next_done_locked(
+    grpc_exec_ctx *exec_ctx, security_handshaker *h, tsi_result result,
+    const unsigned char *bytes_to_send, size_t bytes_to_send_size,
+    tsi_handshaker_result *handshaker_result) {
+  grpc_error *error = GRPC_ERROR_NONE;
+  // Read more if we need to.
+  if (result == TSI_INCOMPLETE_DATA) {
+    GPR_ASSERT(bytes_to_send_size == 0);
+    grpc_endpoint_read(exec_ctx, h->args->endpoint, h->args->read_buffer,
+                       &h->on_handshake_data_received_from_peer);
+    return error;
+  }
   if (result != TSI_OK) {
     return grpc_set_tsi_error_result(
         GRPC_ERROR_CREATE_FROM_STATIC_STRING("Handshake failed"), result);
   }
-  // Send data.
-  grpc_slice to_send =
-      grpc_slice_from_copied_buffer((const char *)h->handshake_buffer, offset);
-  grpc_slice_buffer_reset_and_unref_internal(exec_ctx, &h->outgoing);
-  grpc_slice_buffer_add(&h->outgoing, to_send);
-  grpc_endpoint_write(exec_ctx, h->args->endpoint, &h->outgoing,
-                      &h->on_handshake_data_sent_to_peer);
-  return GRPC_ERROR_NONE;
+  // Update handshaker result.
+  if (handshaker_result != NULL) {
+    GPR_ASSERT(h->handshaker_result == NULL);
+    h->handshaker_result = handshaker_result;
+  }
+  if (bytes_to_send_size > 0) {
+    // Send data to peer, if needed.
+    grpc_slice to_send = grpc_slice_from_copied_buffer(
+        (const char *)bytes_to_send, bytes_to_send_size);
+    grpc_slice_buffer_reset_and_unref_internal(exec_ctx, &h->outgoing);
+    grpc_slice_buffer_add(&h->outgoing, to_send);
+    grpc_endpoint_write(exec_ctx, h->args->endpoint, &h->outgoing,
+                        &h->on_handshake_data_sent_to_peer);
+  } else if (handshaker_result == NULL) {
+    // There is nothing to send, but need to read from peer.
+    grpc_endpoint_read(exec_ctx, h->args->endpoint, h->args->read_buffer,
+                       &h->on_handshake_data_received_from_peer);
+  } else {
+    // Handshake has finished, check peer and so on.
+    error = check_peer_locked(exec_ctx, h);
+  }
+  return error;
+}
+
+static void on_handshake_next_done_grpc_wrapper(
+    tsi_result result, void *user_data, const unsigned char *bytes_to_send,
+    size_t bytes_to_send_size, tsi_handshaker_result *handshaker_result) {
+  security_handshaker *h = user_data;
+  // This callback will be invoked by TSI in a non-grpc thread, so it's
+  // safe to create our own exec_ctx here.
+  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
+  gpr_mu_lock(&h->mu);
+  grpc_error *error =
+      on_handshake_next_done_locked(&exec_ctx, h, result, bytes_to_send,
+                                    bytes_to_send_size, handshaker_result);
+  if (error != GRPC_ERROR_NONE) {
+    security_handshake_failed_locked(&exec_ctx, h, error);
+    gpr_mu_unlock(&h->mu);
+    security_handshaker_unref(&exec_ctx, h);
+  } else {
+    gpr_mu_unlock(&h->mu);
+  }
+  grpc_exec_ctx_finish(&exec_ctx);
+}
+
+static grpc_error *do_handshaker_next_locked(
+    grpc_exec_ctx *exec_ctx, security_handshaker *h,
+    const unsigned char *bytes_received, size_t bytes_received_size) {
+  // Invoke TSI handshaker.
+  unsigned char *bytes_to_send = NULL;
+  size_t bytes_to_send_size = 0;
+  tsi_handshaker_result *handshaker_result = NULL;
+  tsi_result result = tsi_handshaker_next(
+      h->handshaker, bytes_received, bytes_received_size, &bytes_to_send,
+      &bytes_to_send_size, &handshaker_result,
+      &on_handshake_next_done_grpc_wrapper, h);
+  if (result == TSI_ASYNC) {
+    // Handshaker operating asynchronously. Nothing else to do here;
+    // callback will be invoked in a TSI thread.
+    return GRPC_ERROR_NONE;
+  }
+  // Handshaker returned synchronously. Invoke callback directly in
+  // this thread with our existing exec_ctx.
+  return on_handshake_next_done_locked(exec_ctx, h, result, bytes_to_send,
+                                       bytes_to_send_size, handshaker_result);
 }
 
 static void on_handshake_data_received_from_peer(grpc_exec_ctx *exec_ctx,
@@ -241,72 +291,34 @@ static void on_handshake_data_received_from_peer(grpc_exec_ctx *exec_ctx,
     security_handshaker_unref(exec_ctx, h);
     return;
   }
-  // Process received data.
-  tsi_result result = TSI_OK;
-  size_t consumed_slice_size = 0;
+  // Copy all slices received.
   size_t i;
+  size_t bytes_received_size = 0;
   for (i = 0; i < h->args->read_buffer->count; i++) {
-    consumed_slice_size = GRPC_SLICE_LENGTH(h->args->read_buffer->slices[i]);
-    result = tsi_handshaker_process_bytes_from_peer(
-        h->handshaker, GRPC_SLICE_START_PTR(h->args->read_buffer->slices[i]),
-        &consumed_slice_size);
-    if (!tsi_handshaker_is_in_progress(h->handshaker)) break;
+    bytes_received_size += GRPC_SLICE_LENGTH(h->args->read_buffer->slices[i]);
   }
-  if (tsi_handshaker_is_in_progress(h->handshaker)) {
-    /* We may need more data. */
-    if (result == TSI_INCOMPLETE_DATA) {
-      grpc_endpoint_read(exec_ctx, h->args->endpoint, h->args->read_buffer,
-                         &h->on_handshake_data_received_from_peer);
-      goto done;
-    } else {
-      error = send_handshake_bytes_to_peer_locked(exec_ctx, h);
-      if (error != GRPC_ERROR_NONE) {
-        security_handshake_failed_locked(exec_ctx, h, error);
-        gpr_mu_unlock(&h->mu);
-        security_handshaker_unref(exec_ctx, h);
-        return;
-      }
-      goto done;
-    }
+  if (bytes_received_size > h->handshake_buffer_size) {
+    h->handshake_buffer = gpr_realloc(h->handshake_buffer, bytes_received_size);
+    h->handshake_buffer_size = bytes_received_size;
   }
-  if (result != TSI_OK) {
-    security_handshake_failed_locked(
-        exec_ctx, h,
-        grpc_set_tsi_error_result(
-            GRPC_ERROR_CREATE_FROM_STATIC_STRING("Handshake failed"), result));
-    gpr_mu_unlock(&h->mu);
-    security_handshaker_unref(exec_ctx, h);
-    return;
-  }
-  /* Handshake is done and successful this point. */
-  bool has_left_overs_in_current_slice =
-      (consumed_slice_size <
-       GRPC_SLICE_LENGTH(h->args->read_buffer->slices[i]));
-  size_t num_left_overs = (has_left_overs_in_current_slice ? 1 : 0) +
-                          h->args->read_buffer->count - i - 1;
-  if (num_left_overs > 0) {
-    /* Put the leftovers in our buffer (ownership transfered). */
-    if (has_left_overs_in_current_slice) {
-      grpc_slice tail = grpc_slice_split_tail(&h->args->read_buffer->slices[i],
-                                              consumed_slice_size);
-      grpc_slice_buffer_add(&h->left_overs, tail);
-      /* split_tail above increments refcount. */
-      grpc_slice_unref_internal(exec_ctx, tail);
-    }
-    grpc_slice_buffer_addn(
-        &h->left_overs, &h->args->read_buffer->slices[i + 1],
-        num_left_overs - (size_t)has_left_overs_in_current_slice);
+  size_t offset = 0;
+  for (i = 0; i < h->args->read_buffer->count; i++) {
+    size_t slice_size = GPR_SLICE_LENGTH(h->args->read_buffer->slices[i]);
+    memcpy(h->handshake_buffer + offset,
+           GRPC_SLICE_START_PTR(h->args->read_buffer->slices[i]), slice_size);
+    offset += slice_size;
   }
-  // Check peer.
-  error = check_peer_locked(exec_ctx, h);
+  // Call TSI handshaker.
+  error = do_handshaker_next_locked(exec_ctx, h, h->handshake_buffer,
+                                    bytes_received_size);
+
   if (error != GRPC_ERROR_NONE) {
     security_handshake_failed_locked(exec_ctx, h, error);
     gpr_mu_unlock(&h->mu);
     security_handshaker_unref(exec_ctx, h);
-    return;
+  } else {
+    gpr_mu_unlock(&h->mu);
   }
-done:
-  gpr_mu_unlock(&h->mu);
 }
 
 static void on_handshake_data_sent_to_peer(grpc_exec_ctx *exec_ctx, void *arg,
@@ -321,8 +333,8 @@ static void on_handshake_data_sent_to_peer(grpc_exec_ctx *exec_ctx, void *arg,
     security_handshaker_unref(exec_ctx, h);
     return;
   }
-  /* We may be done. */
-  if (tsi_handshaker_is_in_progress(h->handshaker)) {
+  // We may be done.
+  if (h->handshaker_result == NULL) {
     grpc_endpoint_read(exec_ctx, h->args->endpoint, h->args->read_buffer,
                        &h->on_handshake_data_received_from_peer);
   } else {
@@ -371,7 +383,7 @@ static void security_handshaker_do_handshake(grpc_exec_ctx *exec_ctx,
   h->args = args;
   h->on_handshake_done = on_handshake_done;
   gpr_ref(&h->refs);
-  grpc_error *error = send_handshake_bytes_to_peer_locked(exec_ctx, h);
+  grpc_error *error = do_handshaker_next_locked(exec_ctx, h, NULL, 0);
   if (error != GRPC_ERROR_NONE) {
     security_handshake_failed_locked(exec_ctx, h, error);
     gpr_mu_unlock(&h->mu);
@@ -396,15 +408,14 @@ static grpc_handshaker *security_handshaker_create(
   gpr_ref_init(&h->refs, 1);
   h->handshake_buffer_size = GRPC_INITIAL_HANDSHAKE_BUFFER_SIZE;
   h->handshake_buffer = gpr_malloc(h->handshake_buffer_size);
-  grpc_closure_init(&h->on_handshake_data_sent_to_peer,
+  GRPC_CLOSURE_INIT(&h->on_handshake_data_sent_to_peer,
                     on_handshake_data_sent_to_peer, h,
                     grpc_schedule_on_exec_ctx);
-  grpc_closure_init(&h->on_handshake_data_received_from_peer,
+  GRPC_CLOSURE_INIT(&h->on_handshake_data_received_from_peer,
                     on_handshake_data_received_from_peer, h,
                     grpc_schedule_on_exec_ctx);
-  grpc_closure_init(&h->on_peer_checked, on_peer_checked, h,
+  GRPC_CLOSURE_INIT(&h->on_peer_checked, on_peer_checked, h,
                     grpc_schedule_on_exec_ctx);
-  grpc_slice_buffer_init(&h->left_overs);
   grpc_slice_buffer_init(&h->outgoing);
   return &h->base;
 }
@@ -429,7 +440,7 @@ static void fail_handshaker_do_handshake(grpc_exec_ctx *exec_ctx,
                                          grpc_tcp_server_acceptor *acceptor,
                                          grpc_closure *on_handshake_done,
                                          grpc_handshaker_args *args) {
-  grpc_closure_sched(exec_ctx, on_handshake_done,
+  GRPC_CLOSURE_SCHED(exec_ctx, on_handshake_done,
                      GRPC_ERROR_CREATE_FROM_STATIC_STRING(
                          "Failed to create security handshaker"));
 }
diff --git a/src/core/lib/security/transport/security_handshaker.h b/src/core/lib/security/transport/security_handshaker.h
index 0b9eda178f..95bf127fc6 100644
--- a/src/core/lib/security/transport/security_handshaker.h
+++ b/src/core/lib/security/transport/security_handshaker.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/security/transport/server_auth_filter.c b/src/core/lib/security/transport/server_auth_filter.c
index 1aca76f9e8..9bf3f0ca0f 100644
--- a/src/core/lib/security/transport/server_auth_filter.c
+++ b/src/core/lib/security/transport/server_auth_filter.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -42,14 +27,9 @@
 #include "src/core/lib/slice/slice_internal.h"
 
 typedef struct call_data {
-  grpc_metadata_batch *recv_initial_metadata;
-  /* Closure to call when finished with the auth_on_recv hook. */
-  grpc_closure *on_done_recv;
-  /* Receive closures are chained: we inject this closure as the on_done_recv
-     up-call on transport_op, and remember to call our on_done_recv member after
-     handling it. */
-  grpc_closure auth_on_recv;
-  grpc_transport_stream_op_batch *transport_op;
+  grpc_transport_stream_op_batch *recv_initial_metadata_batch;
+  grpc_closure *original_recv_initial_metadata_ready;
+  grpc_closure recv_initial_metadata_ready;
   grpc_metadata_array md;
   const grpc_metadata *consumed_md;
   size_t num_consumed_md;
@@ -105,125 +85,96 @@ static void on_md_processing_done(
     grpc_status_code status, const char *error_details) {
   grpc_call_element *elem = user_data;
   call_data *calld = elem->call_data;
+  grpc_transport_stream_op_batch *batch = calld->recv_initial_metadata_batch;
   grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
-
   /* TODO(jboeuf): Implement support for response_md. */
   if (response_md != NULL && num_response_md > 0) {
     gpr_log(GPR_INFO,
             "response_md in auth metadata processing not supported for now. "
             "Ignoring...");
   }
-
+  grpc_error *error = GRPC_ERROR_NONE;
   if (status == GRPC_STATUS_OK) {
     calld->consumed_md = consumed_md;
     calld->num_consumed_md = num_consumed_md;
-    /* TODO(ctiller): propagate error */
-    GRPC_LOG_IF_ERROR(
-        "grpc_metadata_batch_filter",
-        grpc_metadata_batch_filter(&exec_ctx, calld->recv_initial_metadata,
-                                   remove_consumed_md, elem,
-                                   "Response metadata filtering error"));
-    for (size_t i = 0; i < calld->md.count; i++) {
-      grpc_slice_unref_internal(&exec_ctx, calld->md.metadata[i].key);
-      grpc_slice_unref_internal(&exec_ctx, calld->md.metadata[i].value);
-    }
-    grpc_metadata_array_destroy(&calld->md);
-    grpc_closure_sched(&exec_ctx, calld->on_done_recv, GRPC_ERROR_NONE);
+    error = grpc_metadata_batch_filter(
+        &exec_ctx, batch->payload->recv_initial_metadata.recv_initial_metadata,
+        remove_consumed_md, elem, "Response metadata filtering error");
   } else {
-    for (size_t i = 0; i < calld->md.count; i++) {
-      grpc_slice_unref_internal(&exec_ctx, calld->md.metadata[i].key);
-      grpc_slice_unref_internal(&exec_ctx, calld->md.metadata[i].value);
-    }
-    grpc_metadata_array_destroy(&calld->md);
-    error_details = error_details != NULL
-                        ? error_details
-                        : "Authentication metadata processing failed.";
-    if (calld->transport_op->send_message) {
-      grpc_byte_stream_destroy(
-          &exec_ctx, calld->transport_op->payload->send_message.send_message);
-      calld->transport_op->payload->send_message.send_message = NULL;
+    if (error_details == NULL) {
+      error_details = "Authentication metadata processing failed.";
     }
-    grpc_closure_sched(
-        &exec_ctx, calld->on_done_recv,
+    error =
         grpc_error_set_int(GRPC_ERROR_CREATE_FROM_COPIED_STRING(error_details),
-                           GRPC_ERROR_INT_GRPC_STATUS, status));
+                           GRPC_ERROR_INT_GRPC_STATUS, status);
   }
-
+  for (size_t i = 0; i < calld->md.count; i++) {
+    grpc_slice_unref_internal(&exec_ctx, calld->md.metadata[i].key);
+    grpc_slice_unref_internal(&exec_ctx, calld->md.metadata[i].value);
+  }
+  grpc_metadata_array_destroy(&calld->md);
+  GRPC_CLOSURE_SCHED(&exec_ctx, calld->original_recv_initial_metadata_ready,
+                     error);
   grpc_exec_ctx_finish(&exec_ctx);
 }
 
-static void auth_on_recv(grpc_exec_ctx *exec_ctx, void *user_data,
-                         grpc_error *error) {
-  grpc_call_element *elem = user_data;
-  call_data *calld = elem->call_data;
+static void recv_initial_metadata_ready(grpc_exec_ctx *exec_ctx, void *arg,
+                                        grpc_error *error) {
+  grpc_call_element *elem = arg;
   channel_data *chand = elem->channel_data;
+  call_data *calld = elem->call_data;
+  grpc_transport_stream_op_batch *batch = calld->recv_initial_metadata_batch;
   if (error == GRPC_ERROR_NONE) {
     if (chand->creds != NULL && chand->creds->processor.process != NULL) {
-      calld->md = metadata_batch_to_md_array(calld->recv_initial_metadata);
+      calld->md = metadata_batch_to_md_array(
+          batch->payload->recv_initial_metadata.recv_initial_metadata);
       chand->creds->processor.process(
           chand->creds->processor.state, calld->auth_context,
           calld->md.metadata, calld->md.count, on_md_processing_done, elem);
       return;
     }
   }
-  grpc_closure_sched(exec_ctx, calld->on_done_recv, GRPC_ERROR_REF(error));
+  GRPC_CLOSURE_RUN(exec_ctx, calld->original_recv_initial_metadata_ready,
+                   GRPC_ERROR_REF(error));
 }
 
-static void set_recv_ops_md_callbacks(grpc_call_element *elem,
-                                      grpc_transport_stream_op_batch *op) {
+static void auth_start_transport_stream_op_batch(
+    grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
+    grpc_transport_stream_op_batch *batch) {
   call_data *calld = elem->call_data;
-
-  if (op->recv_initial_metadata) {
-    /* substitute our callback for the higher callback */
-    calld->recv_initial_metadata =
-        op->payload->recv_initial_metadata.recv_initial_metadata;
-    calld->on_done_recv =
-        op->payload->recv_initial_metadata.recv_initial_metadata_ready;
-    op->payload->recv_initial_metadata.recv_initial_metadata_ready =
-        &calld->auth_on_recv;
-    calld->transport_op = op;
+  if (batch->recv_initial_metadata) {
+    // Inject our callback.
+    calld->recv_initial_metadata_batch = batch;
+    calld->original_recv_initial_metadata_ready =
+        batch->payload->recv_initial_metadata.recv_initial_metadata_ready;
+    batch->payload->recv_initial_metadata.recv_initial_metadata_ready =
+        &calld->recv_initial_metadata_ready;
   }
-}
-
-/* Called either:
-     - in response to an API call (or similar) from above, to send something
-     - a network event (or similar) from below, to receive something
-   op contains type and call direction information, in addition to the data
-   that is being sent or received. */
-static void auth_start_transport_op(grpc_exec_ctx *exec_ctx,
-                                    grpc_call_element *elem,
-                                    grpc_transport_stream_op_batch *op) {
-  set_recv_ops_md_callbacks(elem, op);
-  grpc_call_next_op(exec_ctx, elem, op);
+  grpc_call_next_op(exec_ctx, elem, batch);
 }
 
 /* Constructor for call_data */
 static grpc_error *init_call_elem(grpc_exec_ctx *exec_ctx,
                                   grpc_call_element *elem,
                                   const grpc_call_element_args *args) {
-  /* grab pointers to our data from the call element */
   call_data *calld = elem->call_data;
   channel_data *chand = elem->channel_data;
-  grpc_server_security_context *server_ctx = NULL;
-
-  /* initialize members */
-  memset(calld, 0, sizeof(*calld));
-  grpc_closure_init(&calld->auth_on_recv, auth_on_recv, elem,
+  GRPC_CLOSURE_INIT(&calld->recv_initial_metadata_ready,
+                    recv_initial_metadata_ready, elem,
                     grpc_schedule_on_exec_ctx);
-
+  // Create server security context.  Set its auth context from channel
+  // data and save it in the call context.
+  grpc_server_security_context *server_ctx =
+      grpc_server_security_context_create();
+  server_ctx->auth_context = grpc_auth_context_create(chand->auth_context);
+  calld->auth_context = server_ctx->auth_context;
   if (args->context[GRPC_CONTEXT_SECURITY].value != NULL) {
     args->context[GRPC_CONTEXT_SECURITY].destroy(
         args->context[GRPC_CONTEXT_SECURITY].value);
   }
-
-  server_ctx = grpc_server_security_context_create();
-  server_ctx->auth_context = grpc_auth_context_create(chand->auth_context);
-  calld->auth_context = server_ctx->auth_context;
-
   args->context[GRPC_CONTEXT_SECURITY].value = server_ctx;
   args->context[GRPC_CONTEXT_SECURITY].destroy =
       grpc_server_security_context_destroy;
-
   return GRPC_ERROR_NONE;
 }
 
@@ -236,19 +187,15 @@ static void destroy_call_elem(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
 static grpc_error *init_channel_elem(grpc_exec_ctx *exec_ctx,
                                      grpc_channel_element *elem,
                                      grpc_channel_element_args *args) {
+  GPR_ASSERT(!args->is_last);
+  channel_data *chand = elem->channel_data;
   grpc_auth_context *auth_context =
       grpc_find_auth_context_in_args(args->channel_args);
-  grpc_server_credentials *creds =
-      grpc_find_server_credentials_in_args(args->channel_args);
-  /* grab pointers to our data from the channel element */
-  channel_data *chand = elem->channel_data;
-
-  GPR_ASSERT(!args->is_last);
   GPR_ASSERT(auth_context != NULL);
-
-  /* initialize members */
   chand->auth_context =
       GRPC_AUTH_CONTEXT_REF(auth_context, "server_auth_filter");
+  grpc_server_credentials *creds =
+      grpc_find_server_credentials_in_args(args->channel_args);
   chand->creds = grpc_server_credentials_ref(creds);
   return GRPC_ERROR_NONE;
 }
@@ -256,14 +203,13 @@ static grpc_error *init_channel_elem(grpc_exec_ctx *exec_ctx,
 /* Destructor for channel data */
 static void destroy_channel_elem(grpc_exec_ctx *exec_ctx,
                                  grpc_channel_element *elem) {
-  /* grab pointers to our data from the channel element */
   channel_data *chand = elem->channel_data;
   GRPC_AUTH_CONTEXT_UNREF(chand->auth_context, "server_auth_filter");
   grpc_server_credentials_unref(exec_ctx, chand->creds);
 }
 
 const grpc_channel_filter grpc_server_auth_filter = {
-    auth_start_transport_op,
+    auth_start_transport_stream_op_batch,
     grpc_channel_next_op,
     sizeof(call_data),
     init_call_elem,
diff --git a/src/core/lib/security/transport/tsi_error.c b/src/core/lib/security/transport/tsi_error.c
index eae0a676b0..72f9600e84 100644
--- a/src/core/lib/security/transport/tsi_error.c
+++ b/src/core/lib/security/transport/tsi_error.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/security/transport/tsi_error.h b/src/core/lib/security/transport/tsi_error.h
index b84693b5de..87a63a8a7c 100644
--- a/src/core/lib/security/transport/tsi_error.h
+++ b/src/core/lib/security/transport/tsi_error.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/security/util/json_util.c b/src/core/lib/security/util/json_util.c
index 7eed039baa..d847addef9 100644
--- a/src/core/lib/security/util/json_util.c
+++ b/src/core/lib/security/util/json_util.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/security/util/json_util.h b/src/core/lib/security/util/json_util.h
index 137900593f..5ea831e27e 100644
--- a/src/core/lib/security/util/json_util.h
+++ b/src/core/lib/security/util/json_util.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/slice/b64.c b/src/core/lib/slice/b64.c
index d9091646e0..d02f303bdb 100644
--- a/src/core/lib/slice/b64.c
+++ b/src/core/lib/slice/b64.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/slice/b64.h b/src/core/lib/slice/b64.h
index 5cc821f4bf..3fd15febe5 100644
--- a/src/core/lib/slice/b64.h
+++ b/src/core/lib/slice/b64.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/slice/percent_encoding.c b/src/core/lib/slice/percent_encoding.c
index a77c69763f..effc8d7ad6 100644
--- a/src/core/lib/slice/percent_encoding.c
+++ b/src/core/lib/slice/percent_encoding.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/slice/percent_encoding.h b/src/core/lib/slice/percent_encoding.h
index 189bdbe312..faae26a683 100644
--- a/src/core/lib/slice/percent_encoding.h
+++ b/src/core/lib/slice/percent_encoding.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/slice/slice.c b/src/core/lib/slice/slice.c
index b90738fd1a..8a8087805c 100644
--- a/src/core/lib/slice/slice.c
+++ b/src/core/lib/slice/slice.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/slice/slice_buffer.c b/src/core/lib/slice/slice_buffer.c
index e8d41ca0f7..a54a997a0d 100644
--- a/src/core/lib/slice/slice_buffer.c
+++ b/src/core/lib/slice/slice_buffer.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/slice/slice_hash_table.c b/src/core/lib/slice/slice_hash_table.c
index 444f22aa19..1866ed25ac 100644
--- a/src/core/lib/slice/slice_hash_table.c
+++ b/src/core/lib/slice/slice_hash_table.c
@@ -1,32 +1,17 @@
 //
-// Copyright 2016, Google Inc.
-// All rights reserved.
+// Copyright 2016 gRPC authors.
 //
-// Redistribution and use in source and binary forms, with or without
-// modification, are permitted provided that the following conditions are
-// met:
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
 //
-//     * Redistributions of source code must retain the above copyright
-// notice, this list of conditions and the following disclaimer.
-//     * Redistributions in binary form must reproduce the above
-// copyright notice, this list of conditions and the following disclaimer
-// in the documentation and/or other materials provided with the
-// distribution.
-//     * Neither the name of Google Inc. nor the names of its
-// contributors may be used to endorse or promote products derived from
-// this software without specific prior written permission.
+//     http://www.apache.org/licenses/LICENSE-2.0
 //
-// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
 //
 
 #include "src/core/lib/slice/slice_hash_table.h"
@@ -43,6 +28,7 @@
 struct grpc_slice_hash_table {
   gpr_refcount refs;
   void (*destroy_value)(grpc_exec_ctx* exec_ctx, void* value);
+  int (*value_cmp)(void* a, void* b);
   size_t size;
   size_t max_num_probes;
   grpc_slice_hash_table_entry* entries;
@@ -72,10 +58,12 @@ static void grpc_slice_hash_table_add(grpc_slice_hash_table* table,
 
 grpc_slice_hash_table* grpc_slice_hash_table_create(
     size_t num_entries, grpc_slice_hash_table_entry* entries,
-    void (*destroy_value)(grpc_exec_ctx* exec_ctx, void* value)) {
+    void (*destroy_value)(grpc_exec_ctx* exec_ctx, void* value),
+    int (*value_cmp)(void* a, void* b)) {
   grpc_slice_hash_table* table = gpr_zalloc(sizeof(*table));
   gpr_ref_init(&table->refs, 1);
   table->destroy_value = destroy_value;
+  table->value_cmp = value_cmp;
   // Keep load factor low to improve performance of lookups.
   table->size = num_entries * 2;
   const size_t entry_size = sizeof(grpc_slice_hash_table_entry) * table->size;
@@ -121,3 +109,37 @@ void* grpc_slice_hash_table_get(const grpc_slice_hash_table* table,
   }
   return NULL;  // Not found.
 }
+
+static int pointer_cmp(void* a, void* b) { return GPR_ICMP(a, b); }
+int grpc_slice_hash_table_cmp(const grpc_slice_hash_table* a,
+                              const grpc_slice_hash_table* b) {
+  int (*const value_cmp_fn_a)(void* a, void* b) =
+      a->value_cmp != NULL ? a->value_cmp : pointer_cmp;
+  int (*const value_cmp_fn_b)(void* a, void* b) =
+      b->value_cmp != NULL ? b->value_cmp : pointer_cmp;
+  // Compare value_fns
+  const int value_fns_cmp =
+      GPR_ICMP((void*)value_cmp_fn_a, (void*)value_cmp_fn_b);
+  if (value_fns_cmp != 0) return value_fns_cmp;
+  // Compare sizes
+  if (a->size < b->size) return -1;
+  if (a->size > b->size) return 1;
+  // Compare rows.
+  for (size_t i = 0; i < a->size; ++i) {
+    if (is_empty(&a->entries[i])) {
+      if (!is_empty(&b->entries[i])) {
+        return -1;  // a empty but b non-empty
+      }
+      continue;  // both empty, no need to check key or value
+    } else if (is_empty(&b->entries[i])) {
+      return 1;  // a non-empty but b empty
+    }
+    // neither entry is empty
+    const int key_cmp = grpc_slice_cmp(a->entries[i].key, b->entries[i].key);
+    if (key_cmp != 0) return key_cmp;
+    const int value_cmp =
+        value_cmp_fn_a(a->entries[i].value, b->entries[i].value);
+    if (value_cmp != 0) return value_cmp;
+  }
+  return 0;
+}
diff --git a/src/core/lib/slice/slice_hash_table.h b/src/core/lib/slice/slice_hash_table.h
index 1e61c5eb11..339078fef5 100644
--- a/src/core/lib/slice/slice_hash_table.h
+++ b/src/core/lib/slice/slice_hash_table.h
@@ -1,32 +1,17 @@
 /*
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  */
 
 #ifndef GRPC_CORE_LIB_SLICE_SLICE_HASH_TABLE_H
@@ -54,11 +39,15 @@ typedef struct grpc_slice_hash_table_entry {
 } grpc_slice_hash_table_entry;
 
 /** Creates a new hash table of containing \a entries, which is an array
-    of length \a num_entries.  Takes ownership of all keys and values in
-    \a entries.  Values will be cleaned up via \a destroy_value(). */
+    of length \a num_entries.  Takes ownership of all keys and values in \a
+    entries.  Values will be cleaned up via \a destroy_value(). If not NULL, \a
+    value_cmp will be used to compare values in the context of \a
+    grpc_slice_hash_table_cmp. If NULL, raw pointer (\a GPR_ICMP) comparison
+    will be used. */
 grpc_slice_hash_table *grpc_slice_hash_table_create(
     size_t num_entries, grpc_slice_hash_table_entry *entries,
-    void (*destroy_value)(grpc_exec_ctx *exec_ctx, void *value));
+    void (*destroy_value)(grpc_exec_ctx *exec_ctx, void *value),
+    int (*value_cmp)(void *a, void *b));
 
 grpc_slice_hash_table *grpc_slice_hash_table_ref(grpc_slice_hash_table *table);
 void grpc_slice_hash_table_unref(grpc_exec_ctx *exec_ctx,
@@ -69,4 +58,13 @@ void grpc_slice_hash_table_unref(grpc_exec_ctx *exec_ctx,
 void *grpc_slice_hash_table_get(const grpc_slice_hash_table *table,
                                 const grpc_slice key);
 
+/** Compares \a a vs. \a b.
+ * A table is considered "smaller" (resp. "greater") if:
+ *  - GPR_ICMP(a->value_cmp, b->value_cmp) < 1 (resp. > 1),
+ *  - else, it contains fewer (resp. more) entries,
+ *  - else, if strcmp(a_key, b_key) < 1 (resp. > 1),
+ *  - else, if value_cmp(a_value, b_value) < 1 (resp. > 1). */
+int grpc_slice_hash_table_cmp(const grpc_slice_hash_table *a,
+                              const grpc_slice_hash_table *b);
+
 #endif /* GRPC_CORE_LIB_SLICE_SLICE_HASH_TABLE_H */
diff --git a/src/core/lib/slice/slice_intern.c b/src/core/lib/slice/slice_intern.c
index 1c00a2d88e..a6d22c1e1f 100644
--- a/src/core/lib/slice/slice_intern.c
+++ b/src/core/lib/slice/slice_intern.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/slice/slice_internal.h b/src/core/lib/slice/slice_internal.h
index 6467b0a8d6..6df0b4b50b 100644
--- a/src/core/lib/slice/slice_internal.h
+++ b/src/core/lib/slice/slice_internal.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/slice/slice_string_helpers.c b/src/core/lib/slice/slice_string_helpers.c
index 99695007cc..d461c474d2 100644
--- a/src/core/lib/slice/slice_string_helpers.c
+++ b/src/core/lib/slice/slice_string_helpers.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/slice/slice_string_helpers.h b/src/core/lib/slice/slice_string_helpers.h
index 4a4deec6e5..bcfb33bfb3 100644
--- a/src/core/lib/slice/slice_string_helpers.h
+++ b/src/core/lib/slice/slice_string_helpers.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/slice/slice_traits.h b/src/core/lib/slice/slice_traits.h
index 8a283dc65c..4b898bdcd4 100644
--- a/src/core/lib/slice/slice_traits.h
+++ b/src/core/lib/slice/slice_traits.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/support/alloc.c b/src/core/lib/support/alloc.c
index 9973166217..886d69d64c 100644
--- a/src/core/lib/support/alloc.c
+++ b/src/core/lib/support/alloc.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/support/arena.c b/src/core/lib/support/arena.c
index 7bcb983f24..9e0f73ae3d 100644
--- a/src/core/lib/support/arena.c
+++ b/src/core/lib/support/arena.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2017, Google Inc.
- * All rights reserved.
+ * Copyright 2017 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -53,7 +38,7 @@ struct gpr_arena {
 
 gpr_arena *gpr_arena_create(size_t initial_size) {
   initial_size = ROUND_UP_TO_ALIGNMENT_SIZE(initial_size);
-  gpr_arena *a = gpr_zalloc(sizeof(gpr_arena) + initial_size);
+  gpr_arena *a = (gpr_arena *)gpr_zalloc(sizeof(gpr_arena) + initial_size);
   a->initial_zone.size_end = initial_size;
   return a;
 }
@@ -79,7 +64,7 @@ void *gpr_arena_alloc(gpr_arena *arena, size_t size) {
     zone *next_z = (zone *)gpr_atm_acq_load(&z->next_atm);
     if (next_z == NULL) {
       size_t next_z_size = (size_t)gpr_atm_no_barrier_load(&arena->size_so_far);
-      next_z = gpr_zalloc(sizeof(zone) + next_z_size);
+      next_z = (zone *)gpr_zalloc(sizeof(zone) + next_z_size);
       next_z->size_begin = z->size_end;
       next_z->size_end = z->size_end + next_z_size;
       if (!gpr_atm_rel_cas(&z->next_atm, (gpr_atm)NULL, (gpr_atm)next_z)) {
diff --git a/src/core/lib/support/arena.h b/src/core/lib/support/arena.h
index c28033ffc3..47f0e4d16b 100644
--- a/src/core/lib/support/arena.h
+++ b/src/core/lib/support/arena.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2017, Google Inc.
- * All rights reserved.
+ * Copyright 2017 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/support/atm.c b/src/core/lib/support/atm.c
index 06e8432caf..2f37d62f76 100644
--- a/src/core/lib/support/atm.c
+++ b/src/core/lib/support/atm.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2017, Google Inc.
- * All rights reserved.
+ * Copyright 2017 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -36,12 +21,12 @@
 
 gpr_atm gpr_atm_no_barrier_clamped_add(gpr_atm *value, gpr_atm delta,
                                        gpr_atm min, gpr_atm max) {
-  gpr_atm current;
-  gpr_atm new;
+  gpr_atm current_value;
+  gpr_atm new_value;
   do {
-    current = gpr_atm_no_barrier_load(value);
-    new = GPR_CLAMP(current + delta, min, max);
-    if (new == current) break;
-  } while (!gpr_atm_no_barrier_cas(value, current, new));
-  return new;
+    current_value = gpr_atm_no_barrier_load(value);
+    new_value = GPR_CLAMP(current_value + delta, min, max);
+    if (new_value == current_value) break;
+  } while (!gpr_atm_no_barrier_cas(value, current_value, new_value));
+  return new_value;
 }
diff --git a/src/core/lib/support/atomic.h b/src/core/lib/support/atomic.h
index 2226189b68..73c59ae3cd 100644
--- a/src/core/lib/support/atomic.h
+++ b/src/core/lib/support/atomic.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2017, Google Inc.
- * All rights reserved.
+ * Copyright 2017 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/support/atomic_with_atm.h b/src/core/lib/support/atomic_with_atm.h
index 55727f1dee..fe00e9b5bc 100644
--- a/src/core/lib/support/atomic_with_atm.h
+++ b/src/core/lib/support/atomic_with_atm.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2017, Google Inc.
- * All rights reserved.
+ * Copyright 2017 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/support/atomic_with_std.h b/src/core/lib/support/atomic_with_std.h
index 7e9c19efe8..c7a92f7012 100644
--- a/src/core/lib/support/atomic_with_std.h
+++ b/src/core/lib/support/atomic_with_std.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2017, Google Inc.
- * All rights reserved.
+ * Copyright 2017 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/support/avl.c b/src/core/lib/support/avl.c
index ffa10c1e4f..a6178fdbce 100644
--- a/src/core/lib/support/avl.c
+++ b/src/core/lib/support/avl.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -91,7 +76,7 @@ static gpr_avl_node *assert_invariants(gpr_avl_node *n) { return n; }
 
 gpr_avl_node *new_node(void *key, void *value, gpr_avl_node *left,
                        gpr_avl_node *right) {
-  gpr_avl_node *node = gpr_malloc(sizeof(*node));
+  gpr_avl_node *node = (gpr_avl_node *)gpr_malloc(sizeof(*node));
   gpr_ref_init(&node->refs, 1);
   node->key = key;
   node->value = value;
diff --git a/src/core/lib/support/backoff.c b/src/core/lib/support/backoff.c
index 0612472712..6dc0df473b 100644
--- a/src/core/lib/support/backoff.c
+++ b/src/core/lib/support/backoff.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/support/backoff.h b/src/core/lib/support/backoff.h
index 5e9b740824..6e0cc3a4b6 100644
--- a/src/core/lib/support/backoff.h
+++ b/src/core/lib/support/backoff.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/support/block_annotate.h b/src/core/lib/support/block_annotate.h
index 8fb380241f..0a2cb45018 100644
--- a/src/core/lib/support/block_annotate.h
+++ b/src/core/lib/support/block_annotate.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/support/cmdline.c b/src/core/lib/support/cmdline.c
index 88a65a8e2e..9fb80d4460 100644
--- a/src/core/lib/support/cmdline.c
+++ b/src/core/lib/support/cmdline.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -71,7 +56,7 @@ struct gpr_cmdline {
 static int normal_state(gpr_cmdline *cl, char *arg);
 
 gpr_cmdline *gpr_cmdline_create(const char *description) {
-  gpr_cmdline *cl = gpr_zalloc(sizeof(gpr_cmdline));
+  gpr_cmdline *cl = (gpr_cmdline *)gpr_zalloc(sizeof(gpr_cmdline));
 
   cl->description = description;
   cl->state = normal_state;
@@ -100,7 +85,7 @@ static void add_arg(gpr_cmdline *cl, const char *name, const char *help,
     GPR_ASSERT(0 != strcmp(a->name, name));
   }
 
-  a = gpr_zalloc(sizeof(arg));
+  a = (arg *)gpr_zalloc(sizeof(arg));
   a->name = name;
   a->help = help;
   a->type = type;
@@ -302,7 +287,7 @@ static int normal_state(gpr_cmdline *cl, char *str) {
     eq = strchr(str, '=');
     if (eq != NULL) {
       /* copy the string into a temp buffer and extract the name */
-      tmp = arg_name = gpr_malloc((size_t)(eq - str + 1));
+      tmp = arg_name = (char *)gpr_malloc((size_t)(eq - str + 1));
       memcpy(arg_name, str, (size_t)(eq - str));
       arg_name[eq - str] = 0;
     } else {
diff --git a/src/core/lib/support/cpu_iphone.c b/src/core/lib/support/cpu_iphone.c
index 82b49b47bc..dfd69b9fd8 100644
--- a/src/core/lib/support/cpu_iphone.c
+++ b/src/core/lib/support/cpu_iphone.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/support/cpu_linux.c b/src/core/lib/support/cpu_linux.c
index b826dde160..2280668442 100644
--- a/src/core/lib/support/cpu_linux.c
+++ b/src/core/lib/support/cpu_linux.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/support/cpu_posix.c b/src/core/lib/support/cpu_posix.c
index 245f12f06d..a1ba8202a8 100644
--- a/src/core/lib/support/cpu_posix.c
+++ b/src/core/lib/support/cpu_posix.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/support/cpu_windows.c b/src/core/lib/support/cpu_windows.c
index 34d006bfc8..af26ff3679 100644
--- a/src/core/lib/support/cpu_windows.c
+++ b/src/core/lib/support/cpu_windows.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/support/env.h b/src/core/lib/support/env.h
index 6ada5d9390..18bc08ac62 100644
--- a/src/core/lib/support/env.h
+++ b/src/core/lib/support/env.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/support/env_linux.c b/src/core/lib/support/env_linux.c
index 2436eb20b0..0c79a2c401 100644
--- a/src/core/lib/support/env_linux.c
+++ b/src/core/lib/support/env_linux.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/support/env_posix.c b/src/core/lib/support/env_posix.c
index ff47630443..bdbc4da95a 100644
--- a/src/core/lib/support/env_posix.c
+++ b/src/core/lib/support/env_posix.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/support/env_windows.c b/src/core/lib/support/env_windows.c
index 9116959442..c1d557e219 100644
--- a/src/core/lib/support/env_windows.c
+++ b/src/core/lib/support/env_windows.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/support/histogram.c b/src/core/lib/support/histogram.c
index ba8176bb05..6d5ead9aa6 100644
--- a/src/core/lib/support/histogram.c
+++ b/src/core/lib/support/histogram.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -88,7 +73,7 @@ static double bucket_start(gpr_histogram *h, double x) {
 
 gpr_histogram *gpr_histogram_create(double resolution,
                                     double max_bucket_start) {
-  gpr_histogram *h = gpr_malloc(sizeof(gpr_histogram));
+  gpr_histogram *h = (gpr_histogram *)gpr_malloc(sizeof(gpr_histogram));
   GPR_ASSERT(resolution > 0.0);
   GPR_ASSERT(max_bucket_start > resolution);
   h->sum = 0.0;
@@ -102,7 +87,7 @@ gpr_histogram *gpr_histogram_create(double resolution,
   h->num_buckets = bucket_for_unchecked(h, max_bucket_start) + 1;
   GPR_ASSERT(h->num_buckets > 1);
   GPR_ASSERT(h->num_buckets < 100000000);
-  h->buckets = gpr_zalloc(sizeof(uint32_t) * h->num_buckets);
+  h->buckets = (uint32_t *)gpr_zalloc(sizeof(uint32_t) * h->num_buckets);
   return h;
 }
 
diff --git a/src/core/lib/support/host_port.c b/src/core/lib/support/host_port.c
index f19bdbc835..3302e574ab 100644
--- a/src/core/lib/support/host_port.c
+++ b/src/core/lib/support/host_port.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -98,7 +83,7 @@ int gpr_split_host_port(const char *name, char **host, char **port) {
   }
 
   /* Allocate return values. */
-  *host = gpr_malloc(host_len + 1);
+  *host = (char *)gpr_malloc(host_len + 1);
   memcpy(*host, host_start, host_len);
   (*host)[host_len] = '\0';
 
diff --git a/src/core/lib/support/log.c b/src/core/lib/support/log.c
index af1651dae5..bcc336b8ae 100644
--- a/src/core/lib/support/log.c
+++ b/src/core/lib/support/log.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -43,7 +28,7 @@
 #include <string.h>
 
 extern void gpr_default_log(gpr_log_func_args *args);
-static gpr_log_func g_log_func = gpr_default_log;
+static gpr_atm g_log_func = (gpr_atm)gpr_default_log;
 static gpr_atm g_min_severity_to_print = GPR_LOG_VERBOSITY_UNSET;
 
 const char *gpr_log_severity_string(gpr_log_severity severity) {
@@ -70,7 +55,7 @@ void gpr_log_message(const char *file, int line, gpr_log_severity severity,
   lfargs.line = line;
   lfargs.severity = severity;
   lfargs.message = message;
-  g_log_func(&lfargs);
+  ((gpr_log_func)gpr_atm_no_barrier_load(&g_log_func))(&lfargs);
 }
 
 void gpr_set_log_verbosity(gpr_log_severity min_severity_to_print) {
@@ -99,5 +84,5 @@ void gpr_log_verbosity_init() {
 }
 
 void gpr_set_log_function(gpr_log_func f) {
-  g_log_func = f ? f : gpr_default_log;
+  gpr_atm_no_barrier_store(&g_log_func, (gpr_atm)(f ? f : gpr_default_log));
 }
diff --git a/src/core/lib/support/log_android.c b/src/core/lib/support/log_android.c
index 94c8100fd7..6f1cec51f1 100644
--- a/src/core/lib/support/log_android.c
+++ b/src/core/lib/support/log_android.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/support/log_linux.c b/src/core/lib/support/log_linux.c
index 299b377373..61d2346427 100644
--- a/src/core/lib/support/log_linux.c
+++ b/src/core/lib/support/log_linux.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -79,6 +64,8 @@ void gpr_default_log(gpr_log_func_args *args) {
   time_t timer;
   gpr_timespec now = gpr_now(GPR_CLOCK_REALTIME);
   struct tm tm;
+  static __thread long tid = 0;
+  if (tid == 0) tid = gettid();
 
   timer = (time_t)now.tv_sec;
   final_slash = strrchr(args->file, '/');
@@ -96,7 +83,7 @@ void gpr_default_log(gpr_log_func_args *args) {
 
   gpr_asprintf(&prefix, "%s%s.%09" PRId32 " %7ld %s:%d]",
                gpr_log_severity_string(args->severity), time_buffer,
-               now.tv_nsec, gettid(), display_file, args->line);
+               now.tv_nsec, tid, display_file, args->line);
 
   fprintf(stderr, "%-60s %s\n", prefix, args->message);
   gpr_free(prefix);
diff --git a/src/core/lib/support/log_posix.c b/src/core/lib/support/log_posix.c
index 79458dd7a3..8b376fce41 100644
--- a/src/core/lib/support/log_posix.c
+++ b/src/core/lib/support/log_posix.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/support/log_windows.c b/src/core/lib/support/log_windows.c
index ea898c359d..0fdab79ae6 100644
--- a/src/core/lib/support/log_windows.c
+++ b/src/core/lib/support/log_windows.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/support/memory.h b/src/core/lib/support/memory.h
index 6eff94eff7..dc3d32e1c2 100644
--- a/src/core/lib/support/memory.h
+++ b/src/core/lib/support/memory.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2017, Google Inc.
- * All rights reserved.
+ * Copyright 2017 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/support/mpscq.c b/src/core/lib/support/mpscq.c
index 1015cc6776..e9f893988d 100644
--- a/src/core/lib/support/mpscq.c
+++ b/src/core/lib/support/mpscq.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/support/mpscq.h b/src/core/lib/support/mpscq.h
index 24c89f90c9..daa51768f7 100644
--- a/src/core/lib/support/mpscq.h
+++ b/src/core/lib/support/mpscq.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -62,7 +47,6 @@ void gpr_mpscq_push(gpr_mpscq *q, gpr_mpscq_node *n);
 // Pop a node (returns NULL if no node is ready - which doesn't indicate that
 // the queue is empty!!)
 gpr_mpscq_node *gpr_mpscq_pop(gpr_mpscq *q);
-
 // Pop a node; sets *empty to true if the queue is empty, or false if it is not
 gpr_mpscq_node *gpr_mpscq_pop_and_check_end(gpr_mpscq *q, bool *empty);
 
diff --git a/src/core/lib/support/murmur_hash.c b/src/core/lib/support/murmur_hash.c
index 7137c1f313..f329611818 100644
--- a/src/core/lib/support/murmur_hash.c
+++ b/src/core/lib/support/murmur_hash.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/support/murmur_hash.h b/src/core/lib/support/murmur_hash.h
index 6d282ff358..7510b4d09c 100644
--- a/src/core/lib/support/murmur_hash.h
+++ b/src/core/lib/support/murmur_hash.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/support/spinlock.h b/src/core/lib/support/spinlock.h
index d8c7c5ffde..37adda11b0 100644
--- a/src/core/lib/support/spinlock.h
+++ b/src/core/lib/support/spinlock.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/support/stack_lockfree.c b/src/core/lib/support/stack_lockfree.c
index dfbd3fb125..0fb64ed001 100644
--- a/src/core/lib/support/stack_lockfree.c
+++ b/src/core/lib/support/stack_lockfree.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/support/stack_lockfree.h b/src/core/lib/support/stack_lockfree.h
index 35ef7c2959..6324211b72 100644
--- a/src/core/lib/support/stack_lockfree.h
+++ b/src/core/lib/support/stack_lockfree.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/support/string.c b/src/core/lib/support/string.c
index d20b86f7cf..b65009754a 100644
--- a/src/core/lib/support/string.c
+++ b/src/core/lib/support/string.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -53,7 +38,7 @@ char *gpr_strdup(const char *src) {
   }
 
   len = strlen(src) + 1;
-  dst = gpr_malloc(len);
+  dst = (char *)gpr_malloc(len);
 
   memcpy(dst, src, len);
 
@@ -74,13 +59,13 @@ static dump_out dump_out_create(void) {
 static void dump_out_append(dump_out *out, char c) {
   if (out->length == out->capacity) {
     out->capacity = GPR_MAX(8, 2 * out->capacity);
-    out->data = gpr_realloc(out->data, out->capacity);
+    out->data = (char *)gpr_realloc(out->data, out->capacity);
   }
   out->data[out->length++] = c;
 }
 
 static void hexdump(dump_out *out, const char *buf, size_t len) {
-  static const char hex[16] = "0123456789abcdef";
+  static const char *hex = "0123456789abcdef";
 
   const uint8_t *const beg = (const uint8_t *)buf;
   const uint8_t *const end = beg + len;
@@ -124,16 +109,16 @@ char *gpr_dump(const char *buf, size_t len, uint32_t flags) {
 
 int gpr_parse_bytes_to_uint32(const char *buf, size_t len, uint32_t *result) {
   uint32_t out = 0;
-  uint32_t new;
+  uint32_t new_val;
   size_t i;
 
   if (len == 0) return 0; /* must have some bytes */
 
   for (i = 0; i < len; i++) {
     if (buf[i] < '0' || buf[i] > '9') return 0; /* bad char */
-    new = 10 * out + (uint32_t)(buf[i] - '0');
-    if (new < out) return 0; /* overflow */
-    out = new;
+    new_val = 10 * out + (uint32_t)(buf[i] - '0');
+    if (new_val < out) return 0; /* overflow */
+    out = new_val;
   }
 
   *result = out;
@@ -201,7 +186,7 @@ int gpr_parse_nonnegative_int(const char *value) {
 char *gpr_leftpad(const char *str, char flag, size_t length) {
   const size_t str_length = strlen(str);
   const size_t out_length = str_length > length ? str_length : length;
-  char *out = gpr_malloc(out_length + 1);
+  char *out = (char *)gpr_malloc(out_length + 1);
   memset(out, flag, out_length - str_length);
   memcpy(out + out_length - str_length, str, str_length);
   out[out_length] = 0;
@@ -225,7 +210,7 @@ char *gpr_strjoin_sep(const char **strs, size_t nstrs, const char *sep,
   if (nstrs > 0) {
     out_length += sep_len * (nstrs - 1); /* separators */
   }
-  out = gpr_malloc(out_length);
+  out = (char *)gpr_malloc(out_length);
   out_length = 0;
   for (i = 0; i < nstrs; i++) {
     const size_t slen = strlen(strs[i]);
@@ -256,7 +241,7 @@ void gpr_strvec_destroy(gpr_strvec *sv) {
 void gpr_strvec_add(gpr_strvec *sv, char *str) {
   if (sv->count == sv->capacity) {
     sv->capacity = GPR_MAX(sv->capacity + 8, sv->capacity * 2);
-    sv->strs = gpr_realloc(sv->strs, sizeof(char *) * sv->capacity);
+    sv->strs = (char **)gpr_realloc(sv->strs, sizeof(char *) * sv->capacity);
   }
   sv->strs[sv->count++] = str;
 }
@@ -278,12 +263,12 @@ int gpr_stricmp(const char *a, const char *b) {
 
 static void add_string_to_split(const char *beg, const char *end, char ***strs,
                                 size_t *nstrs, size_t *capstrs) {
-  char *out = gpr_malloc((size_t)(end - beg) + 1);
+  char *out = (char *)gpr_malloc((size_t)(end - beg) + 1);
   memcpy(out, beg, (size_t)(end - beg));
   out[end - beg] = 0;
   if (*nstrs == *capstrs) {
     *capstrs = GPR_MAX(8, 2 * *capstrs);
-    *strs = gpr_realloc(*strs, sizeof(*strs) * *capstrs);
+    *strs = (char **)gpr_realloc(*strs, sizeof(*strs) * *capstrs);
   }
   (*strs)[*nstrs] = out;
   ++*nstrs;
diff --git a/src/core/lib/support/string.h b/src/core/lib/support/string.h
index d1c52faed4..e11df8439d 100644
--- a/src/core/lib/support/string.h
+++ b/src/core/lib/support/string.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/support/string_posix.c b/src/core/lib/support/string_posix.c
index c804ed5ded..e768faf739 100644
--- a/src/core/lib/support/string_posix.c
+++ b/src/core/lib/support/string_posix.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -58,7 +43,7 @@ int gpr_asprintf(char **strp, const char *format, ...) {
 
   /* Allocate a new buffer, with space for the NUL terminator. */
   strp_buflen = (size_t)ret + 1;
-  if ((*strp = gpr_malloc(strp_buflen)) == NULL) {
+  if ((*strp = (char *)gpr_malloc(strp_buflen)) == NULL) {
     /* This shouldn't happen, because gpr_malloc() calls abort(). */
     return -1;
   }
diff --git a/src/core/lib/support/string_util_windows.c b/src/core/lib/support/string_util_windows.c
index 049c9a8c04..2a03404448 100644
--- a/src/core/lib/support/string_util_windows.c
+++ b/src/core/lib/support/string_util_windows.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/support/string_windows.c b/src/core/lib/support/string_windows.c
index ecc2a3a4e5..50278d9559 100644
--- a/src/core/lib/support/string_windows.c
+++ b/src/core/lib/support/string_windows.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/support/string_windows.h b/src/core/lib/support/string_windows.h
index 899563b72d..7c7f31e7aa 100644
--- a/src/core/lib/support/string_windows.h
+++ b/src/core/lib/support/string_windows.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/support/subprocess_posix.c b/src/core/lib/support/subprocess_posix.c
index ed653b9c2e..af75162ee9 100644
--- a/src/core/lib/support/subprocess_posix.c
+++ b/src/core/lib/support/subprocess_posix.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -67,7 +52,7 @@ gpr_subprocess *gpr_subprocess_create(int argc, const char **argv) {
   if (pid == -1) {
     return NULL;
   } else if (pid == 0) {
-    exec_args = gpr_malloc(((size_t)argc + 1) * sizeof(char *));
+    exec_args = (char **)gpr_malloc(((size_t)argc + 1) * sizeof(char *));
     memcpy(exec_args, argv, (size_t)argc * sizeof(char *));
     exec_args[argc] = NULL;
     execv(exec_args[0], exec_args);
@@ -76,7 +61,7 @@ gpr_subprocess *gpr_subprocess_create(int argc, const char **argv) {
     _exit(1);
     return NULL;
   } else {
-    r = gpr_zalloc(sizeof(gpr_subprocess));
+    r = (gpr_subprocess *)gpr_zalloc(sizeof(gpr_subprocess));
     r->pid = pid;
     return r;
   }
diff --git a/src/core/lib/support/subprocess_windows.c b/src/core/lib/support/subprocess_windows.c
index dee8c44ac1..7412f8d344 100644
--- a/src/core/lib/support/subprocess_windows.c
+++ b/src/core/lib/support/subprocess_windows.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/support/sync.c b/src/core/lib/support/sync.c
index b52f004f74..994dcb0e14 100644
--- a/src/core/lib/support/sync.c
+++ b/src/core/lib/support/sync.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/support/sync_posix.c b/src/core/lib/support/sync_posix.c
index 16e7d6e12a..62d800b18c 100644
--- a/src/core/lib/support/sync_posix.c
+++ b/src/core/lib/support/sync_posix.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/support/sync_windows.c b/src/core/lib/support/sync_windows.c
index 8f0e8ff69f..008c5aecba 100644
--- a/src/core/lib/support/sync_windows.c
+++ b/src/core/lib/support/sync_windows.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/support/thd.c b/src/core/lib/support/thd.c
index 40f53a18e5..ca62615d65 100644
--- a/src/core/lib/support/thd.c
+++ b/src/core/lib/support/thd.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/support/thd_internal.h b/src/core/lib/support/thd_internal.h
index 975d5537cc..cc468c7846 100644
--- a/src/core/lib/support/thd_internal.h
+++ b/src/core/lib/support/thd_internal.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/support/thd_posix.c b/src/core/lib/support/thd_posix.c
index 2fc23bffaf..98afd10df7 100644
--- a/src/core/lib/support/thd_posix.c
+++ b/src/core/lib/support/thd_posix.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -65,7 +50,7 @@ int gpr_thd_new(gpr_thd_id *t, void (*thd_body)(void *arg), void *arg,
   pthread_t p;
   /* don't use gpr_malloc as we may cause an infinite recursion with
    * the profiling code */
-  struct thd_arg *a = malloc(sizeof(*a));
+  struct thd_arg *a = (struct thd_arg *)malloc(sizeof(*a));
   GPR_ASSERT(a != NULL);
   a->body = thd_body;
   a->arg = arg;
diff --git a/src/core/lib/support/thd_windows.c b/src/core/lib/support/thd_windows.c
index 74d2250df4..54533e9412 100644
--- a/src/core/lib/support/thd_windows.c
+++ b/src/core/lib/support/thd_windows.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/support/time.c b/src/core/lib/support/time.c
index c5f94d46f7..6903674d75 100644
--- a/src/core/lib/support/time.c
+++ b/src/core/lib/support/time.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/support/time_posix.c b/src/core/lib/support/time_posix.c
index 9bfec7782a..3ead40d807 100644
--- a/src/core/lib/support/time_posix.c
+++ b/src/core/lib/support/time_posix.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/support/time_precise.c b/src/core/lib/support/time_precise.c
index a2cf74bc84..6ce19e53cc 100644
--- a/src/core/lib/support/time_precise.c
+++ b/src/core/lib/support/time_precise.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -37,26 +22,26 @@
 
 #ifdef GRPC_TIMERS_RDTSC
 #if defined(__i386__)
-static void gpr_get_cycle_counter(long long int *clk) {
-  long long int ret;
+static void gpr_get_cycle_counter(int64_t int *clk) {
+  int64_t int ret;
   __asm__ volatile("rdtsc" : "=A"(ret));
   *clk = ret;
 }
 
 // ----------------------------------------------------------------
 #elif defined(__x86_64__) || defined(__amd64__)
-static void gpr_get_cycle_counter(long long int *clk) {
-  unsigned long long low, high;
+static void gpr_get_cycle_counter(int64_t *clk) {
+  uint64_t low, high;
   __asm__ volatile("rdtsc" : "=a"(low), "=d"(high));
-  *clk = (long long)(high << 32) | (long long)low;
+  *clk = (int64_t)(high << 32) | (int64_t)low;
 }
 #endif
 
 static double cycles_per_second = 0;
-static long long int start_cycle;
+static int64_t start_cycle;
 void gpr_precise_clock_init(void) {
   time_t start;
-  long long end_cycle;
+  int64_t end_cycle;
   gpr_log(GPR_DEBUG, "Calibrating timers");
   start = time(NULL);
   while (time(NULL) == start)
@@ -70,7 +55,7 @@ void gpr_precise_clock_init(void) {
 }
 
 void gpr_precise_clock_now(gpr_timespec *clk) {
-  long long int counter;
+  int64_t counter;
   double secs;
   gpr_get_cycle_counter(&counter);
   secs = (double)(counter - start_cycle) / cycles_per_second;
diff --git a/src/core/lib/support/time_precise.h b/src/core/lib/support/time_precise.h
index 30818d04b9..aa28d6d7c4 100644
--- a/src/core/lib/support/time_precise.h
+++ b/src/core/lib/support/time_precise.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/support/time_windows.c b/src/core/lib/support/time_windows.c
index 7b94a5b7bf..40df3761c0 100644
--- a/src/core/lib/support/time_windows.c
+++ b/src/core/lib/support/time_windows.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/support/tls_pthread.c b/src/core/lib/support/tls_pthread.c
index 9683a6e547..9ebee577fe 100644
--- a/src/core/lib/support/tls_pthread.c
+++ b/src/core/lib/support/tls_pthread.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/support/tmpfile.h b/src/core/lib/support/tmpfile.h
index f613cf9bc8..caa1d0f4d2 100644
--- a/src/core/lib/support/tmpfile.h
+++ b/src/core/lib/support/tmpfile.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/support/tmpfile_msys.c b/src/core/lib/support/tmpfile_msys.c
index 4f566c4c28..614c0a4a18 100644
--- a/src/core/lib/support/tmpfile_msys.c
+++ b/src/core/lib/support/tmpfile_msys.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/support/tmpfile_posix.c b/src/core/lib/support/tmpfile_posix.c
index 5771c158e0..7ad3af0a57 100644
--- a/src/core/lib/support/tmpfile_posix.c
+++ b/src/core/lib/support/tmpfile_posix.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/support/tmpfile_windows.c b/src/core/lib/support/tmpfile_windows.c
index 542f53e589..47b4510a72 100644
--- a/src/core/lib/support/tmpfile_windows.c
+++ b/src/core/lib/support/tmpfile_windows.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/support/wrap_memcpy.c b/src/core/lib/support/wrap_memcpy.c
index deb8d6b198..cff056dc3b 100644
--- a/src/core/lib/support/wrap_memcpy.c
+++ b/src/core/lib/support/wrap_memcpy.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/surface/alarm.c b/src/core/lib/surface/alarm.c
index 6593f14523..911ac010e0 100644
--- a/src/core/lib/surface/alarm.c
+++ b/src/core/lib/surface/alarm.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -65,7 +50,7 @@ grpc_alarm *grpc_alarm_create(grpc_completion_queue *cq, gpr_timespec deadline,
   alarm->tag = tag;
 
   grpc_cq_begin_op(cq, tag);
-  grpc_closure_init(&alarm->on_alarm, alarm_cb, alarm,
+  GRPC_CLOSURE_INIT(&alarm->on_alarm, alarm_cb, alarm,
                     grpc_schedule_on_exec_ctx);
   grpc_timer_init(&exec_ctx, &alarm->alarm,
                   grpc_timespec_to_millis(&exec_ctx, deadline),
diff --git a/src/core/lib/surface/api_trace.c b/src/core/lib/surface/api_trace.c
index d8941cdf42..56973303da 100644
--- a/src/core/lib/surface/api_trace.c
+++ b/src/core/lib/surface/api_trace.c
@@ -1,37 +1,22 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
 #include "src/core/lib/surface/api_trace.h"
 #include "src/core/lib/debug/trace.h"
 
-grpc_tracer_flag grpc_api_trace = GRPC_TRACER_INITIALIZER(false);
+grpc_tracer_flag grpc_api_trace = GRPC_TRACER_INITIALIZER(false, "api");
diff --git a/src/core/lib/surface/api_trace.h b/src/core/lib/surface/api_trace.h
index d4fbc8d90d..849cbaaef6 100644
--- a/src/core/lib/surface/api_trace.h
+++ b/src/core/lib/surface/api_trace.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/surface/byte_buffer.c b/src/core/lib/surface/byte_buffer.c
index c8e2fdfdad..0bc990d487 100644
--- a/src/core/lib/surface/byte_buffer.c
+++ b/src/core/lib/surface/byte_buffer.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/surface/byte_buffer_reader.c b/src/core/lib/surface/byte_buffer_reader.c
index 539b014278..87bd3239c0 100644
--- a/src/core/lib/surface/byte_buffer_reader.c
+++ b/src/core/lib/surface/byte_buffer_reader.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/surface/call.c b/src/core/lib/surface/call.c
index 201969cd45..2365d27307 100644
--- a/src/core/lib/surface/call.c
+++ b/src/core/lib/surface/call.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -244,8 +229,10 @@ struct grpc_call {
   void *saved_receiving_stream_ready_bctlp;
 };
 
-grpc_tracer_flag grpc_call_error_trace = GRPC_TRACER_INITIALIZER(false);
-grpc_tracer_flag grpc_compression_trace = GRPC_TRACER_INITIALIZER(false);
+grpc_tracer_flag grpc_call_error_trace =
+    GRPC_TRACER_INITIALIZER(false, "call_error");
+grpc_tracer_flag grpc_compression_trace =
+    GRPC_TRACER_INITIALIZER(false, "compression");
 
 #define CALL_STACK_FROM_CALL(call) ((grpc_call_stack *)((call) + 1))
 #define CALL_FROM_CALL_STACK(call_stack) (((grpc_call *)(call_stack)) - 1)
@@ -472,7 +459,7 @@ void grpc_call_set_completion_queue(grpc_exec_ctx *exec_ctx, grpc_call *call,
       exec_ctx, CALL_STACK_FROM_CALL(call), &call->pollent);
 }
 
-#ifdef GRPC_STREAM_REFCOUNT_DEBUG
+#ifndef NDEBUG
 #define REF_REASON reason
 #define REF_ARG , const char *reason
 #else
@@ -535,7 +522,7 @@ static void destroy_call(grpc_exec_ctx *exec_ctx, void *call,
   }
 
   grpc_call_stack_destroy(exec_ctx, CALL_STACK_FROM_CALL(c), &c->final_info,
-                          grpc_closure_init(&c->release_call, release_call, c,
+                          GRPC_CLOSURE_INIT(&c->release_call, release_call, c,
                                             grpc_schedule_on_exec_ctx));
   GPR_TIMER_END("destroy_call", 0);
 }
@@ -649,7 +636,7 @@ static void cancel_with_error(grpc_exec_ctx *exec_ctx, grpc_call *c,
   GRPC_CALL_INTERNAL_REF(c, "termination");
   set_status_from_error(exec_ctx, c, source, GRPC_ERROR_REF(error));
   grpc_transport_stream_op_batch *op = grpc_make_transport_stream_op(
-      grpc_closure_create(done_termination, c, grpc_schedule_on_exec_ctx));
+      GRPC_CLOSURE_CREATE(done_termination, c, grpc_schedule_on_exec_ctx));
   op->cancel_stream = true;
   op->payload->cancel_stream.cancel_error = error;
   execute_op(exec_ctx, c, op);
@@ -944,33 +931,6 @@ static grpc_compression_algorithm decode_compression(grpc_mdelem md) {
   return algorithm;
 }
 
-static void recv_common_filter(grpc_exec_ctx *exec_ctx, grpc_call *call,
-                               grpc_metadata_batch *b) {
-  if (b->idx.named.grpc_status != NULL) {
-    uint32_t status_code = decode_status(b->idx.named.grpc_status->md);
-    grpc_error *error =
-        status_code == GRPC_STATUS_OK
-            ? GRPC_ERROR_NONE
-            : grpc_error_set_int(GRPC_ERROR_CREATE_FROM_STATIC_STRING(
-                                     "Error received from peer"),
-                                 GRPC_ERROR_INT_GRPC_STATUS,
-                                 (intptr_t)status_code);
-
-    if (b->idx.named.grpc_message != NULL) {
-      error = grpc_error_set_str(
-          error, GRPC_ERROR_STR_GRPC_MESSAGE,
-          grpc_slice_ref_internal(GRPC_MDVALUE(b->idx.named.grpc_message->md)));
-      grpc_metadata_batch_remove(exec_ctx, b, b->idx.named.grpc_message);
-    } else if (error != GRPC_ERROR_NONE) {
-      error = grpc_error_set_str(error, GRPC_ERROR_STR_GRPC_MESSAGE,
-                                 grpc_empty_slice());
-    }
-
-    set_status_from_error(exec_ctx, call, STATUS_FROM_WIRE, error);
-    grpc_metadata_batch_remove(exec_ctx, b, b->idx.named.grpc_status);
-  }
-}
-
 static void publish_app_metadata(grpc_call *call, grpc_metadata_batch *b,
                                  int is_trailing) {
   if (b->list.count == 0) return;
@@ -995,8 +955,6 @@ static void publish_app_metadata(grpc_call *call, grpc_metadata_batch *b,
 
 static void recv_initial_filter(grpc_exec_ctx *exec_ctx, grpc_call *call,
                                 grpc_metadata_batch *b) {
-  recv_common_filter(exec_ctx, call, b);
-
   if (b->idx.named.grpc_encoding != NULL) {
     GPR_TIMER_BEGIN("incoming_compression_algorithm", 0);
     set_incoming_compression_algorithm(
@@ -1004,7 +962,6 @@ static void recv_initial_filter(grpc_exec_ctx *exec_ctx, grpc_call *call,
     GPR_TIMER_END("incoming_compression_algorithm", 0);
     grpc_metadata_batch_remove(exec_ctx, b, b->idx.named.grpc_encoding);
   }
-
   if (b->idx.named.grpc_accept_encoding != NULL) {
     GPR_TIMER_BEGIN("encodings_accepted_by_peer", 0);
     set_encodings_accepted_by_peer(exec_ctx, call,
@@ -1012,14 +969,33 @@ static void recv_initial_filter(grpc_exec_ctx *exec_ctx, grpc_call *call,
     grpc_metadata_batch_remove(exec_ctx, b, b->idx.named.grpc_accept_encoding);
     GPR_TIMER_END("encodings_accepted_by_peer", 0);
   }
-
   publish_app_metadata(call, b, false);
 }
 
 static void recv_trailing_filter(grpc_exec_ctx *exec_ctx, void *args,
                                  grpc_metadata_batch *b) {
   grpc_call *call = args;
-  recv_common_filter(exec_ctx, call, b);
+  if (b->idx.named.grpc_status != NULL) {
+    uint32_t status_code = decode_status(b->idx.named.grpc_status->md);
+    grpc_error *error =
+        status_code == GRPC_STATUS_OK
+            ? GRPC_ERROR_NONE
+            : grpc_error_set_int(GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+                                     "Error received from peer"),
+                                 GRPC_ERROR_INT_GRPC_STATUS,
+                                 (intptr_t)status_code);
+    if (b->idx.named.grpc_message != NULL) {
+      error = grpc_error_set_str(
+          error, GRPC_ERROR_STR_GRPC_MESSAGE,
+          grpc_slice_ref_internal(GRPC_MDVALUE(b->idx.named.grpc_message->md)));
+      grpc_metadata_batch_remove(exec_ctx, b, b->idx.named.grpc_message);
+    } else if (error != GRPC_ERROR_NONE) {
+      error = grpc_error_set_str(error, GRPC_ERROR_STR_GRPC_MESSAGE,
+                                 grpc_empty_slice());
+    }
+    set_status_from_error(exec_ctx, call, STATUS_FROM_WIRE, error);
+    grpc_metadata_batch_remove(exec_ctx, b, b->idx.named.grpc_status);
+  }
   publish_app_metadata(call, b, true);
 }
 
@@ -1185,7 +1161,7 @@ static void post_batch_completion(grpc_exec_ctx *exec_ctx,
   if (bctl->completion_data.notify_tag.is_closure) {
     /* unrefs bctl->error */
     bctl->call = NULL;
-    grpc_closure_run(exec_ctx, bctl->completion_data.notify_tag.tag, error);
+    GRPC_CLOSURE_RUN(exec_ctx, bctl->completion_data.notify_tag.tag, error);
     GRPC_CALL_INTERNAL_UNREF(exec_ctx, call, "completion");
   } else {
     /* unrefs bctl->error */
@@ -1290,7 +1266,7 @@ static void process_data_after_md(grpc_exec_ctx *exec_ctx,
     } else {
       *call->receiving_buffer = grpc_raw_byte_buffer_create(NULL, 0);
     }
-    grpc_closure_init(&call->receiving_slice_ready, receiving_slice_ready, bctl,
+    GRPC_CLOSURE_INIT(&call->receiving_slice_ready, receiving_slice_ready, bctl,
                       grpc_schedule_on_exec_ctx);
     continue_receiving_slices(exec_ctx, bctl);
   }
@@ -1405,11 +1381,11 @@ static void receiving_initial_metadata_ready(grpc_exec_ctx *exec_ctx,
 
   call->has_initial_md_been_received = true;
   if (call->saved_receiving_stream_ready_bctlp != NULL) {
-    grpc_closure *saved_rsr_closure = grpc_closure_create(
+    grpc_closure *saved_rsr_closure = GRPC_CLOSURE_CREATE(
         receiving_stream_ready, call->saved_receiving_stream_ready_bctlp,
         grpc_schedule_on_exec_ctx);
     call->saved_receiving_stream_ready_bctlp = NULL;
-    grpc_closure_run(exec_ctx, saved_rsr_closure, GRPC_ERROR_REF(error));
+    GRPC_CLOSURE_RUN(exec_ctx, saved_rsr_closure, GRPC_ERROR_REF(error));
   }
 
   finish_batch_step(exec_ctx, bctl);
@@ -1451,7 +1427,7 @@ static grpc_call_error call_start_batch(grpc_exec_ctx *exec_ctx,
                      free_no_op_completion, NULL,
                      gpr_malloc(sizeof(grpc_cq_completion)));
     } else {
-      grpc_closure_sched(exec_ctx, notify_tag, GRPC_ERROR_NONE);
+      GRPC_CLOSURE_SCHED(exec_ctx, notify_tag, GRPC_ERROR_NONE);
     }
     error = GRPC_CALL_OK;
     goto done;
@@ -1468,7 +1444,6 @@ static grpc_call_error call_start_batch(grpc_exec_ctx *exec_ctx,
   grpc_transport_stream_op_batch *stream_op = &bctl->op;
   grpc_transport_stream_op_batch_payload *stream_op_payload =
       &call->stream_op_payload;
-  stream_op->covered_by_poller = true;
 
   /* rewrite batch ops into a transport op */
   for (i = 0; i < nops; i++) {
@@ -1531,7 +1506,9 @@ static grpc_call_error call_start_batch(grpc_exec_ctx *exec_ctx,
           goto done_with_error;
         }
         /* TODO(ctiller): just make these the same variable? */
-        call->metadata_batch[0][0].deadline = call->send_deadline;
+        if (call->is_client) {
+          call->metadata_batch[0][0].deadline = call->send_deadline;
+        }
         stream_op_payload->send_initial_metadata.send_initial_metadata =
             &call->metadata_batch[0 /* is_receiving */][0 /* is_trailing */];
         stream_op_payload->send_initial_metadata.send_initial_metadata_flags =
@@ -1657,14 +1634,10 @@ static grpc_call_error call_start_batch(grpc_exec_ctx *exec_ctx,
           error = GRPC_CALL_ERROR_TOO_MANY_OPERATIONS;
           goto done_with_error;
         }
-        /* IF this is a server, then GRPC_OP_RECV_INITIAL_METADATA *must* come
-           from server.c. In that case, it's coming from accept_stream, and in
-           that case we're not necessarily covered by a poller. */
-        stream_op->covered_by_poller = call->is_client;
         call->received_initial_metadata = true;
         call->buffered_metadata[0] =
             op->data.recv_initial_metadata.recv_initial_metadata;
-        grpc_closure_init(&call->receiving_initial_metadata_ready,
+        GRPC_CLOSURE_INIT(&call->receiving_initial_metadata_ready,
                           receiving_initial_metadata_ready, bctl,
                           grpc_schedule_on_exec_ctx);
         stream_op->recv_initial_metadata = true;
@@ -1688,7 +1661,7 @@ static grpc_call_error call_start_batch(grpc_exec_ctx *exec_ctx,
         stream_op->recv_message = true;
         call->receiving_buffer = op->data.recv_message.recv_message;
         stream_op_payload->recv_message.recv_message = &call->receiving_stream;
-        grpc_closure_init(&call->receiving_stream_ready, receiving_stream_ready,
+        GRPC_CLOSURE_INIT(&call->receiving_stream_ready, receiving_stream_ready,
                           bctl, grpc_schedule_on_exec_ctx);
         stream_op_payload->recv_message.recv_message_ready =
             &call->receiving_stream_ready;
@@ -1754,7 +1727,7 @@ static grpc_call_error call_start_batch(grpc_exec_ctx *exec_ctx,
   }
   gpr_ref_init(&bctl->steps_to_complete, num_completion_callbacks_needed);
 
-  grpc_closure_init(&bctl->finish_batch, finish_batch, bctl,
+  GRPC_CLOSURE_INIT(&bctl->finish_batch, finish_batch, bctl,
                     grpc_schedule_on_exec_ctx);
   stream_op->on_complete = &bctl->finish_batch;
   gpr_atm_rel_store(&call->any_ops_sent_atm, 1);
diff --git a/src/core/lib/surface/call.h b/src/core/lib/surface/call.h
index 256a5fa2fe..185bfccb77 100644
--- a/src/core/lib/surface/call.h
+++ b/src/core/lib/surface/call.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -77,7 +62,7 @@ grpc_error *grpc_call_create(grpc_exec_ctx *exec_ctx,
 void grpc_call_set_completion_queue(grpc_exec_ctx *exec_ctx, grpc_call *call,
                                     grpc_completion_queue *cq);
 
-#ifdef GRPC_STREAM_REFCOUNT_DEBUG
+#ifndef NDEBUG
 void grpc_call_internal_ref(grpc_call *call, const char *reason);
 void grpc_call_internal_unref(grpc_exec_ctx *exec_ctx, grpc_call *call,
                               const char *reason);
diff --git a/src/core/lib/surface/call_details.c b/src/core/lib/surface/call_details.c
index d0f88e1969..ea9208c7e3 100644
--- a/src/core/lib/surface/call_details.c
+++ b/src/core/lib/surface/call_details.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/surface/call_log_batch.c b/src/core/lib/surface/call_log_batch.c
index 529a1ef0f5..4443aba58a 100644
--- a/src/core/lib/surface/call_log_batch.c
+++ b/src/core/lib/surface/call_log_batch.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/surface/call_test_only.h b/src/core/lib/surface/call_test_only.h
index 47088991d3..2f1b80bfd7 100644
--- a/src/core/lib/surface/call_test_only.h
+++ b/src/core/lib/surface/call_test_only.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/surface/channel.c b/src/core/lib/surface/channel.c
index b3ba826bbc..5780a18ce8 100644
--- a/src/core/lib/surface/channel.c
+++ b/src/core/lib/surface/channel.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -360,7 +345,7 @@ grpc_call *grpc_channel_create_registered_call(
   return call;
 }
 
-#ifdef GRPC_STREAM_REFCOUNT_DEBUG
+#ifndef NDEBUG
 #define REF_REASON reason
 #define REF_ARG , const char *reason
 #else
diff --git a/src/core/lib/surface/channel.h b/src/core/lib/surface/channel.h
index 0f203a3e59..528bb868e2 100644
--- a/src/core/lib/surface/channel.h
+++ b/src/core/lib/surface/channel.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -74,7 +59,7 @@ grpc_mdelem grpc_channel_get_reffed_status_elem(grpc_exec_ctx *exec_ctx,
 size_t grpc_channel_get_call_size_estimate(grpc_channel *channel);
 void grpc_channel_update_call_size_estimate(grpc_channel *channel, size_t size);
 
-#ifdef GRPC_STREAM_REFCOUNT_DEBUG
+#ifndef NDEBUG
 void grpc_channel_internal_ref(grpc_channel *channel, const char *reason);
 void grpc_channel_internal_unref(grpc_exec_ctx *exec_ctx, grpc_channel *channel,
                                  const char *reason);
diff --git a/src/core/lib/surface/channel_init.c b/src/core/lib/surface/channel_init.c
index 20f5753004..a1391ffe56 100644
--- a/src/core/lib/surface/channel_init.c
+++ b/src/core/lib/surface/channel_init.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/surface/channel_init.h b/src/core/lib/surface/channel_init.h
index 411f5eae18..5f109332ad 100644
--- a/src/core/lib/surface/channel_init.h
+++ b/src/core/lib/surface/channel_init.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/surface/channel_ping.c b/src/core/lib/surface/channel_ping.c
index e68febdddf..80eb80af78 100644
--- a/src/core/lib/surface/channel_ping.c
+++ b/src/core/lib/surface/channel_ping.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -71,7 +56,7 @@ void grpc_channel_ping(grpc_channel *channel, grpc_completion_queue *cq,
   GPR_ASSERT(reserved == NULL);
   pr->tag = tag;
   pr->cq = cq;
-  grpc_closure_init(&pr->closure, ping_done, pr, grpc_schedule_on_exec_ctx);
+  GRPC_CLOSURE_INIT(&pr->closure, ping_done, pr, grpc_schedule_on_exec_ctx);
   op->send_ping = &pr->closure;
   op->bind_pollset = grpc_cq_pollset(cq);
   grpc_cq_begin_op(cq, tag);
diff --git a/src/core/lib/surface/channel_stack_type.c b/src/core/lib/surface/channel_stack_type.c
index ed3b53fb36..5f5c877727 100644
--- a/src/core/lib/surface/channel_stack_type.c
+++ b/src/core/lib/surface/channel_stack_type.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/surface/channel_stack_type.h b/src/core/lib/surface/channel_stack_type.h
index ccf4e53d27..3f0e14ffc0 100644
--- a/src/core/lib/surface/channel_stack_type.h
+++ b/src/core/lib/surface/channel_stack_type.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/surface/completion_queue.c b/src/core/lib/surface/completion_queue.c
index d26df33b5c..cefa8a2a89 100644
--- a/src/core/lib/surface/completion_queue.c
+++ b/src/core/lib/surface/completion_queue.c
@@ -1,36 +1,20 @@
 /*
  *
- * Copyright 2015-2016, Google Inc.
- * All rights reserved.
+ * Copyright 2015-2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
-
 #include "src/core/lib/surface/completion_queue.h"
 
 #include <stdio.h>
@@ -45,14 +29,19 @@
 #include "src/core/lib/iomgr/pollset.h"
 #include "src/core/lib/iomgr/timer.h"
 #include "src/core/lib/profiling/timers.h"
+#include "src/core/lib/support/spinlock.h"
 #include "src/core/lib/support/string.h"
 #include "src/core/lib/surface/api_trace.h"
 #include "src/core/lib/surface/call.h"
 #include "src/core/lib/surface/event_string.h"
 
-grpc_tracer_flag grpc_trace_operation_failures = GRPC_TRACER_INITIALIZER(false);
+grpc_tracer_flag grpc_trace_operation_failures =
+    GRPC_TRACER_INITIALIZER(false, "op_failure");
 #ifndef NDEBUG
-grpc_tracer_flag grpc_trace_pending_tags = GRPC_TRACER_INITIALIZER(false);
+grpc_tracer_flag grpc_trace_pending_tags =
+    GRPC_TRACER_INITIALIZER(false, "pending_tags");
+grpc_tracer_flag grpc_trace_cq_refcount =
+    GRPC_TRACER_INITIALIZER(false, "cq_refcount");
 #endif
 
 typedef struct {
@@ -129,7 +118,7 @@ static grpc_error *non_polling_poller_work(grpc_exec_ctx *exec_ctx,
     npp->root = w.next;
     if (&w == npp->root) {
       if (npp->shutdown) {
-        grpc_closure_sched(exec_ctx, npp->shutdown, GRPC_ERROR_NONE);
+        GRPC_CLOSURE_SCHED(exec_ctx, npp->shutdown, GRPC_ERROR_NONE);
       }
       npp->root = NULL;
     }
@@ -162,7 +151,7 @@ static void non_polling_poller_shutdown(grpc_exec_ctx *exec_ctx,
   GPR_ASSERT(closure != NULL);
   p->shutdown = closure;
   if (p->root == NULL) {
-    grpc_closure_sched(exec_ctx, closure, GRPC_ERROR_NONE);
+    GRPC_CLOSURE_SCHED(exec_ctx, closure, GRPC_ERROR_NONE);
   } else {
     non_polling_worker *w = p->root;
     do {
@@ -202,35 +191,83 @@ static const cq_poller_vtable g_poller_vtable_by_poller_type[] = {
      .destroy = non_polling_poller_destroy},
 };
 
-/* Completion queue structure */
-struct grpc_completion_queue {
-  /** owned by pollset */
-  gpr_mu *mu;
+typedef struct cq_vtable {
+  grpc_cq_completion_type cq_completion_type;
+  size_t data_size;
+  void (*init)(void *data);
+  void (*shutdown)(grpc_exec_ctx *exec_ctx, grpc_completion_queue *cq);
+  void (*destroy)(void *data);
+  void (*begin_op)(grpc_completion_queue *cq, void *tag);
+  void (*end_op)(grpc_exec_ctx *exec_ctx, grpc_completion_queue *cq, void *tag,
+                 grpc_error *error,
+                 void (*done)(grpc_exec_ctx *exec_ctx, void *done_arg,
+                              grpc_cq_completion *storage),
+                 void *done_arg, grpc_cq_completion *storage);
+  grpc_event (*next)(grpc_completion_queue *cq, gpr_timespec deadline,
+                     void *reserved);
+  grpc_event (*pluck)(grpc_completion_queue *cq, void *tag,
+                      gpr_timespec deadline, void *reserved);
+} cq_vtable;
+
+/* Queue that holds the cq_completion_events. Internally uses gpr_mpscq queue
+ * (a lockfree multiproducer single consumer queue). It uses a queue_lock
+ * to support multiple consumers.
+ * Only used in completion queues whose completion_type is GRPC_CQ_NEXT */
+typedef struct grpc_cq_event_queue {
+  /* Spinlock to serialize consumers i.e pop() operations */
+  gpr_spinlock queue_lock;
+
+  gpr_mpscq queue;
+
+  /* A lazy counter of number of items in the queue. This is NOT atomically
+     incremented/decremented along with push/pop operations and hence is only
+     eventually consistent */
+  gpr_atm num_queue_items;
+} grpc_cq_event_queue;
+
+typedef struct cq_next_data {
+  /** Completed events for completion-queues of type GRPC_CQ_NEXT */
+  grpc_cq_event_queue queue;
+
+  /** Counter of how many things have ever been queued on this completion queue
+      useful for avoiding locks to check the queue */
+  gpr_atm things_queued_ever;
 
-  grpc_cq_completion_type completion_type;
+  /* Number of outstanding events (+1 if not shut down) */
+  gpr_atm pending_events;
 
-  const cq_poller_vtable *poller_vtable;
+  int shutdown_called;
+} cq_next_data;
 
-  /** completed events */
+typedef struct cq_pluck_data {
+  /** Completed events for completion-queues of type GRPC_CQ_PLUCK */
   grpc_cq_completion completed_head;
   grpc_cq_completion *completed_tail;
+
   /** Number of pending events (+1 if we're not shutdown) */
   gpr_refcount pending_events;
-  /** Once owning_refs drops to zero, we will destroy the cq */
-  gpr_refcount owning_refs;
-  /** counter of how many things have ever been queued on this completion queue
+
+  /** Counter of how many things have ever been queued on this completion queue
       useful for avoiding locks to check the queue */
   gpr_atm things_queued_ever;
+
   /** 0 initially, 1 once we've begun shutting down */
-  int shutdown;
+  gpr_atm shutdown;
   int shutdown_called;
-  int is_server_cq;
-  /** Can the server cq accept incoming channels */
-  /* TODO: sreek - This will no longer be needed. Use polling_type set */
-  int is_non_listening_server_cq;
+
   int num_pluckers;
   plucker pluckers[GRPC_MAX_COMPLETION_QUEUE_PLUCKERS];
-  grpc_closure pollset_shutdown_done;
+} cq_pluck_data;
+
+/* Completion queue structure */
+struct grpc_completion_queue {
+  /** Once owning_refs drops to zero, we will destroy the cq */
+  gpr_refcount owning_refs;
+
+  gpr_mu *mu;
+
+  const cq_vtable *vtable;
+  const cq_poller_vtable *poller_vtable;
 
 #ifndef NDEBUG
   void **outstanding_tags;
@@ -238,14 +275,82 @@ struct grpc_completion_queue {
   size_t outstanding_tag_capacity;
 #endif
 
-  grpc_completion_queue *next_free;
+  grpc_closure pollset_shutdown_done;
+  int num_polls;
 };
 
-#define POLLSET_FROM_CQ(cq) ((grpc_pollset *)(cq + 1))
-#define CQ_FROM_POLLSET(ps) (((grpc_completion_queue *)ps) - 1)
+/* Forward declarations */
+static void cq_finish_shutdown_next(grpc_exec_ctx *exec_ctx,
+                                    grpc_completion_queue *cq);
+static void cq_finish_shutdown_pluck(grpc_exec_ctx *exec_ctx,
+                                     grpc_completion_queue *cq);
+static void cq_shutdown_next(grpc_exec_ctx *exec_ctx,
+                             grpc_completion_queue *cq);
+static void cq_shutdown_pluck(grpc_exec_ctx *exec_ctx,
+                              grpc_completion_queue *cq);
+
+static void cq_begin_op_for_next(grpc_completion_queue *cq, void *tag);
+static void cq_begin_op_for_pluck(grpc_completion_queue *cq, void *tag);
+
+static void cq_end_op_for_next(grpc_exec_ctx *exec_ctx,
+                               grpc_completion_queue *cq, void *tag,
+                               grpc_error *error,
+                               void (*done)(grpc_exec_ctx *exec_ctx,
+                                            void *done_arg,
+                                            grpc_cq_completion *storage),
+                               void *done_arg, grpc_cq_completion *storage);
+
+static void cq_end_op_for_pluck(grpc_exec_ctx *exec_ctx,
+                                grpc_completion_queue *cq, void *tag,
+                                grpc_error *error,
+                                void (*done)(grpc_exec_ctx *exec_ctx,
+                                             void *done_arg,
+                                             grpc_cq_completion *storage),
+                                void *done_arg, grpc_cq_completion *storage);
+
+static grpc_event cq_next(grpc_completion_queue *cq, gpr_timespec deadline,
+                          void *reserved);
+
+static grpc_event cq_pluck(grpc_completion_queue *cq, void *tag,
+                           gpr_timespec deadline, void *reserved);
+
+static void cq_init_next(void *data);
+static void cq_init_pluck(void *data);
+static void cq_destroy_next(void *data);
+static void cq_destroy_pluck(void *data);
+
+/* Completion queue vtables based on the completion-type */
+static const cq_vtable g_cq_vtable[] = {
+    /* GRPC_CQ_NEXT */
+    {.data_size = sizeof(cq_next_data),
+     .cq_completion_type = GRPC_CQ_NEXT,
+     .init = cq_init_next,
+     .shutdown = cq_shutdown_next,
+     .destroy = cq_destroy_next,
+     .begin_op = cq_begin_op_for_next,
+     .end_op = cq_end_op_for_next,
+     .next = cq_next,
+     .pluck = NULL},
+    /* GRPC_CQ_PLUCK */
+    {.data_size = sizeof(cq_pluck_data),
+     .cq_completion_type = GRPC_CQ_PLUCK,
+     .init = cq_init_pluck,
+     .shutdown = cq_shutdown_pluck,
+     .destroy = cq_destroy_pluck,
+     .begin_op = cq_begin_op_for_pluck,
+     .end_op = cq_end_op_for_pluck,
+     .next = NULL,
+     .pluck = cq_pluck},
+};
+
+#define DATA_FROM_CQ(cq) ((void *)(cq + 1))
+#define POLLSET_FROM_CQ(cq) \
+  ((grpc_pollset *)(cq->vtable->data_size + (char *)DATA_FROM_CQ(cq)))
 
-grpc_tracer_flag grpc_cq_pluck_trace = GRPC_TRACER_INITIALIZER(true);
-grpc_tracer_flag grpc_cq_event_timeout_trace = GRPC_TRACER_INITIALIZER(true);
+grpc_tracer_flag grpc_cq_pluck_trace =
+    GRPC_TRACER_INITIALIZER(true, "queue_pluck");
+grpc_tracer_flag grpc_cq_event_timeout_trace =
+    GRPC_TRACER_INITIALIZER(true, "queue_timeout");
 
 #define GRPC_SURFACE_TRACE_RETURNED_EVENT(cq, event)    \
   if (GRPC_TRACER_ON(grpc_api_trace) &&                 \
@@ -256,13 +361,48 @@ grpc_tracer_flag grpc_cq_event_timeout_trace = GRPC_TRACER_INITIALIZER(true);
     gpr_free(_ev);                                      \
   }
 
-static void on_pollset_shutdown_done(grpc_exec_ctx *exec_ctx, void *cc,
+static void on_pollset_shutdown_done(grpc_exec_ctx *exec_ctx, void *cq,
                                      grpc_error *error);
 
+static void cq_event_queue_init(grpc_cq_event_queue *q) {
+  gpr_mpscq_init(&q->queue);
+  q->queue_lock = GPR_SPINLOCK_INITIALIZER;
+  gpr_atm_no_barrier_store(&q->num_queue_items, 0);
+}
+
+static void cq_event_queue_destroy(grpc_cq_event_queue *q) {
+  gpr_mpscq_destroy(&q->queue);
+}
+
+static bool cq_event_queue_push(grpc_cq_event_queue *q, grpc_cq_completion *c) {
+  gpr_mpscq_push(&q->queue, (gpr_mpscq_node *)c);
+  return gpr_atm_no_barrier_fetch_add(&q->num_queue_items, 1) == 0;
+}
+
+static grpc_cq_completion *cq_event_queue_pop(grpc_cq_event_queue *q) {
+  grpc_cq_completion *c = NULL;
+  if (gpr_spinlock_trylock(&q->queue_lock)) {
+    c = (grpc_cq_completion *)gpr_mpscq_pop(&q->queue);
+    gpr_spinlock_unlock(&q->queue_lock);
+  }
+
+  if (c) {
+    gpr_atm_no_barrier_fetch_add(&q->num_queue_items, -1);
+  }
+
+  return c;
+}
+
+/* Note: The counter is not incremented/decremented atomically with push/pop.
+ * The count is only eventually consistent */
+static long cq_event_queue_num_items(grpc_cq_event_queue *q) {
+  return (long)gpr_atm_no_barrier_load(&q->num_queue_items);
+}
+
 grpc_completion_queue *grpc_completion_queue_create_internal(
     grpc_cq_completion_type completion_type,
     grpc_cq_polling_type polling_type) {
-  grpc_completion_queue *cc;
+  grpc_completion_queue *cq;
 
   GPR_TIMER_BEGIN("grpc_completion_queue_create_internal", 0);
 
@@ -271,163 +411,307 @@ grpc_completion_queue *grpc_completion_queue_create_internal(
       "polling_type=%d)",
       2, (completion_type, polling_type));
 
+  const cq_vtable *vtable = &g_cq_vtable[completion_type];
   const cq_poller_vtable *poller_vtable =
       &g_poller_vtable_by_poller_type[polling_type];
 
-  cc = gpr_zalloc(sizeof(grpc_completion_queue) + poller_vtable->size());
-  poller_vtable->init(POLLSET_FROM_CQ(cc), &cc->mu);
-#ifndef NDEBUG
-  cc->outstanding_tags = NULL;
-  cc->outstanding_tag_capacity = 0;
-#endif
+  cq = gpr_zalloc(sizeof(grpc_completion_queue) + vtable->data_size +
+                  poller_vtable->size());
 
-  cc->completion_type = completion_type;
-  cc->poller_vtable = poller_vtable;
+  cq->vtable = vtable;
+  cq->poller_vtable = poller_vtable;
 
-  /* Initial ref is dropped by grpc_completion_queue_shutdown */
-  gpr_ref_init(&cc->pending_events, 1);
   /* One for destroy(), one for pollset_shutdown */
-  gpr_ref_init(&cc->owning_refs, 2);
-  cc->completed_tail = &cc->completed_head;
-  cc->completed_head.next = (uintptr_t)cc->completed_tail;
-  cc->shutdown = 0;
-  cc->shutdown_called = 0;
-  cc->is_server_cq = 0;
-  cc->is_non_listening_server_cq = 0;
-  cc->num_pluckers = 0;
-  gpr_atm_no_barrier_store(&cc->things_queued_ever, 0);
-#ifndef NDEBUG
-  cc->outstanding_tag_count = 0;
-#endif
-  grpc_closure_init(&cc->pollset_shutdown_done, on_pollset_shutdown_done, cc,
+  gpr_ref_init(&cq->owning_refs, 2);
+
+  poller_vtable->init(POLLSET_FROM_CQ(cq), &cq->mu);
+  vtable->init(DATA_FROM_CQ(cq));
+
+  GRPC_CLOSURE_INIT(&cq->pollset_shutdown_done, on_pollset_shutdown_done, cq,
                     grpc_schedule_on_exec_ctx);
 
   GPR_TIMER_END("grpc_completion_queue_create_internal", 0);
 
-  return cc;
+  return cq;
 }
 
-grpc_cq_completion_type grpc_get_cq_completion_type(grpc_completion_queue *cc) {
-  return cc->completion_type;
+static void cq_init_next(void *ptr) {
+  cq_next_data *cqd = ptr;
+  /* Initial ref is dropped by grpc_completion_queue_shutdown */
+  gpr_atm_no_barrier_store(&cqd->pending_events, 1);
+  cqd->shutdown_called = false;
+  gpr_atm_no_barrier_store(&cqd->things_queued_ever, 0);
+  cq_event_queue_init(&cqd->queue);
+}
+
+static void cq_destroy_next(void *ptr) {
+  cq_next_data *cqd = ptr;
+  GPR_ASSERT(cq_event_queue_num_items(&cqd->queue) == 0);
+  cq_event_queue_destroy(&cqd->queue);
+}
+
+static void cq_init_pluck(void *ptr) {
+  cq_pluck_data *cqd = ptr;
+  /* Initial ref is dropped by grpc_completion_queue_shutdown */
+  gpr_ref_init(&cqd->pending_events, 1);
+  cqd->completed_tail = &cqd->completed_head;
+  cqd->completed_head.next = (uintptr_t)cqd->completed_tail;
+  gpr_atm_no_barrier_store(&cqd->shutdown, 0);
+  cqd->shutdown_called = 0;
+  cqd->num_pluckers = 0;
+  gpr_atm_no_barrier_store(&cqd->things_queued_ever, 0);
 }
 
-#ifdef GRPC_CQ_REF_COUNT_DEBUG
-void grpc_cq_internal_ref(grpc_completion_queue *cc, const char *reason,
+static void cq_destroy_pluck(void *ptr) {
+  cq_pluck_data *cqd = ptr;
+  GPR_ASSERT(cqd->completed_head.next == (uintptr_t)&cqd->completed_head);
+}
+
+grpc_cq_completion_type grpc_get_cq_completion_type(grpc_completion_queue *cq) {
+  return cq->vtable->cq_completion_type;
+}
+
+int grpc_get_cq_poll_num(grpc_completion_queue *cq) {
+  int cur_num_polls;
+  gpr_mu_lock(cq->mu);
+  cur_num_polls = cq->num_polls;
+  gpr_mu_unlock(cq->mu);
+  return cur_num_polls;
+}
+
+#ifndef NDEBUG
+void grpc_cq_internal_ref(grpc_completion_queue *cq, const char *reason,
                           const char *file, int line) {
-  gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG, "CQ:%p   ref %d -> %d %s", cc,
-          (int)cc->owning_refs.count, (int)cc->owning_refs.count + 1, reason);
+  if (GRPC_TRACER_ON(grpc_trace_cq_refcount)) {
+    gpr_atm val = gpr_atm_no_barrier_load(&cq->owning_refs.count);
+    gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
+            "CQ:%p   ref %" PRIdPTR " -> %" PRIdPTR " %s", cq, val, val + 1,
+            reason);
+  }
 #else
-void grpc_cq_internal_ref(grpc_completion_queue *cc) {
+void grpc_cq_internal_ref(grpc_completion_queue *cq) {
 #endif
-  gpr_ref(&cc->owning_refs);
+  gpr_ref(&cq->owning_refs);
 }
 
 static void on_pollset_shutdown_done(grpc_exec_ctx *exec_ctx, void *arg,
                                      grpc_error *error) {
-  grpc_completion_queue *cc = arg;
-  GRPC_CQ_INTERNAL_UNREF(exec_ctx, cc, "pollset_destroy");
+  grpc_completion_queue *cq = arg;
+  GRPC_CQ_INTERNAL_UNREF(exec_ctx, cq, "pollset_destroy");
 }
 
-#ifdef GRPC_CQ_REF_COUNT_DEBUG
-void grpc_cq_internal_unref(grpc_exec_ctx *exec_ctx, grpc_completion_queue *cc,
+#ifndef NDEBUG
+void grpc_cq_internal_unref(grpc_exec_ctx *exec_ctx, grpc_completion_queue *cq,
                             const char *reason, const char *file, int line) {
-  gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG, "CQ:%p unref %d -> %d %s", cc,
-          (int)cc->owning_refs.count, (int)cc->owning_refs.count - 1, reason);
+  if (GRPC_TRACER_ON(grpc_trace_cq_refcount)) {
+    gpr_atm val = gpr_atm_no_barrier_load(&cq->owning_refs.count);
+    gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
+            "CQ:%p unref %" PRIdPTR " -> %" PRIdPTR " %s", cq, val, val - 1,
+            reason);
+  }
 #else
 void grpc_cq_internal_unref(grpc_exec_ctx *exec_ctx,
-                            grpc_completion_queue *cc) {
+                            grpc_completion_queue *cq) {
 #endif
-  if (gpr_unref(&cc->owning_refs)) {
-    GPR_ASSERT(cc->completed_head.next == (uintptr_t)&cc->completed_head);
-    cc->poller_vtable->destroy(exec_ctx, POLLSET_FROM_CQ(cc));
+  if (gpr_unref(&cq->owning_refs)) {
+    cq->vtable->destroy(DATA_FROM_CQ(cq));
+    cq->poller_vtable->destroy(exec_ctx, POLLSET_FROM_CQ(cq));
 #ifndef NDEBUG
-    gpr_free(cc->outstanding_tags);
+    gpr_free(cq->outstanding_tags);
 #endif
-    gpr_free(cc);
+    gpr_free(cq);
   }
 }
 
-void grpc_cq_begin_op(grpc_completion_queue *cc, void *tag) {
+static void cq_begin_op_for_next(grpc_completion_queue *cq, void *tag) {
+  cq_next_data *cqd = DATA_FROM_CQ(cq);
+  GPR_ASSERT(!cqd->shutdown_called);
+  gpr_atm_no_barrier_fetch_add(&cqd->pending_events, 1);
+}
+
+static void cq_begin_op_for_pluck(grpc_completion_queue *cq, void *tag) {
+  cq_pluck_data *cqd = DATA_FROM_CQ(cq);
+  GPR_ASSERT(!cqd->shutdown_called);
+  gpr_ref(&cqd->pending_events);
+}
+
+void grpc_cq_begin_op(grpc_completion_queue *cq, void *tag) {
 #ifndef NDEBUG
-  gpr_mu_lock(cc->mu);
-  GPR_ASSERT(!cc->shutdown_called);
-  if (cc->outstanding_tag_count == cc->outstanding_tag_capacity) {
-    cc->outstanding_tag_capacity = GPR_MAX(4, 2 * cc->outstanding_tag_capacity);
-    cc->outstanding_tags =
-        gpr_realloc(cc->outstanding_tags, sizeof(*cc->outstanding_tags) *
-                                              cc->outstanding_tag_capacity);
+  gpr_mu_lock(cq->mu);
+  if (cq->outstanding_tag_count == cq->outstanding_tag_capacity) {
+    cq->outstanding_tag_capacity = GPR_MAX(4, 2 * cq->outstanding_tag_capacity);
+    cq->outstanding_tags =
+        gpr_realloc(cq->outstanding_tags, sizeof(*cq->outstanding_tags) *
+                                              cq->outstanding_tag_capacity);
   }
-  cc->outstanding_tags[cc->outstanding_tag_count++] = tag;
-  gpr_mu_unlock(cc->mu);
+  cq->outstanding_tags[cq->outstanding_tag_count++] = tag;
+  gpr_mu_unlock(cq->mu);
 #endif
-  gpr_ref(&cc->pending_events);
+  cq->vtable->begin_op(cq, tag);
 }
 
-/* Signal the end of an operation - if this is the last waiting-to-be-queued
-   event, then enter shutdown mode */
-/* Queue a GRPC_OP_COMPLETED operation */
-void grpc_cq_end_op(grpc_exec_ctx *exec_ctx, grpc_completion_queue *cc,
-                    void *tag, grpc_error *error,
-                    void (*done)(grpc_exec_ctx *exec_ctx, void *done_arg,
-                                 grpc_cq_completion *storage),
-                    void *done_arg, grpc_cq_completion *storage) {
-  int shutdown;
-  int i;
-  grpc_pollset_worker *pluck_worker;
 #ifndef NDEBUG
+static void cq_check_tag(grpc_completion_queue *cq, void *tag, bool lock_cq) {
   int found = 0;
+  if (lock_cq) {
+    gpr_mu_lock(cq->mu);
+  }
+
+  for (int i = 0; i < (int)cq->outstanding_tag_count; i++) {
+    if (cq->outstanding_tags[i] == tag) {
+      cq->outstanding_tag_count--;
+      GPR_SWAP(void *, cq->outstanding_tags[i],
+               cq->outstanding_tags[cq->outstanding_tag_count]);
+      found = 1;
+      break;
+    }
+  }
+
+  if (lock_cq) {
+    gpr_mu_unlock(cq->mu);
+  }
+
+  GPR_ASSERT(found);
+}
+#else
+static void cq_check_tag(grpc_completion_queue *cq, void *tag, bool lock_cq) {}
 #endif
 
-  GPR_TIMER_BEGIN("grpc_cq_end_op", 0);
+/* Queue a GRPC_OP_COMPLETED operation to a completion queue (with a
+ * completion
+ * type of GRPC_CQ_NEXT) */
+static void cq_end_op_for_next(grpc_exec_ctx *exec_ctx,
+                               grpc_completion_queue *cq, void *tag,
+                               grpc_error *error,
+                               void (*done)(grpc_exec_ctx *exec_ctx,
+                                            void *done_arg,
+                                            grpc_cq_completion *storage),
+                               void *done_arg, grpc_cq_completion *storage) {
+  GPR_TIMER_BEGIN("cq_end_op_for_next", 0);
+
   if (GRPC_TRACER_ON(grpc_api_trace) ||
       (GRPC_TRACER_ON(grpc_trace_operation_failures) &&
        error != GRPC_ERROR_NONE)) {
     const char *errmsg = grpc_error_string(error);
     GRPC_API_TRACE(
-        "grpc_cq_end_op(exec_ctx=%p, cc=%p, tag=%p, error=%s, done=%p, "
-        "done_arg=%p, storage=%p)",
-        7, (exec_ctx, cc, tag, errmsg, done, done_arg, storage));
+        "cq_end_op_for_next(exec_ctx=%p, cq=%p, tag=%p, error=%s, "
+        "done=%p, done_arg=%p, storage=%p)",
+        7, (exec_ctx, cq, tag, errmsg, done, done_arg, storage));
     if (GRPC_TRACER_ON(grpc_trace_operation_failures) &&
         error != GRPC_ERROR_NONE) {
       gpr_log(GPR_ERROR, "Operation failed: tag=%p, error=%s", tag, errmsg);
     }
   }
 
+  cq_next_data *cqd = DATA_FROM_CQ(cq);
+  int is_success = (error == GRPC_ERROR_NONE);
+
   storage->tag = tag;
   storage->done = done;
   storage->done_arg = done_arg;
-  storage->next = ((uintptr_t)&cc->completed_head) |
-                  ((uintptr_t)(error == GRPC_ERROR_NONE));
+  storage->next = (uintptr_t)(is_success);
+
+  cq_check_tag(cq, tag, true); /* Used in debug builds only */
+
+  /* Add the completion to the queue */
+  bool is_first = cq_event_queue_push(&cqd->queue, storage);
+  gpr_atm_no_barrier_fetch_add(&cqd->things_queued_ever, 1);
+  bool will_definitely_shutdown =
+      gpr_atm_no_barrier_load(&cqd->pending_events) == 1;
+
+  if (!will_definitely_shutdown) {
+    /* Only kick if this is the first item queued */
+    if (is_first) {
+      gpr_mu_lock(cq->mu);
+      grpc_error *kick_error =
+          cq->poller_vtable->kick(POLLSET_FROM_CQ(cq), NULL);
+      gpr_mu_unlock(cq->mu);
 
-  gpr_mu_lock(cc->mu);
-#ifndef NDEBUG
-  for (i = 0; i < (int)cc->outstanding_tag_count; i++) {
-    if (cc->outstanding_tags[i] == tag) {
-      cc->outstanding_tag_count--;
-      GPR_SWAP(void *, cc->outstanding_tags[i],
-               cc->outstanding_tags[cc->outstanding_tag_count]);
-      found = 1;
-      break;
+      if (kick_error != GRPC_ERROR_NONE) {
+        const char *msg = grpc_error_string(kick_error);
+        gpr_log(GPR_ERROR, "Kick failed: %s", msg);
+        GRPC_ERROR_UNREF(kick_error);
+      }
+    }
+    if (gpr_atm_full_fetch_add(&cqd->pending_events, -1) == 1) {
+      GRPC_CQ_INTERNAL_REF(cq, "shutting_down");
+      gpr_mu_lock(cq->mu);
+      cq_finish_shutdown_next(exec_ctx, cq);
+      gpr_mu_unlock(cq->mu);
+      GRPC_CQ_INTERNAL_UNREF(exec_ctx, cq, "shutting_down");
     }
+  } else {
+    GRPC_CQ_INTERNAL_REF(cq, "shutting_down");
+    gpr_atm_rel_store(&cqd->pending_events, 0);
+    gpr_mu_lock(cq->mu);
+    cq_finish_shutdown_next(exec_ctx, cq);
+    gpr_mu_unlock(cq->mu);
+    GRPC_CQ_INTERNAL_UNREF(exec_ctx, cq, "shutting_down");
   }
-  GPR_ASSERT(found);
-#endif
-  shutdown = gpr_unref(&cc->pending_events);
-  gpr_atm_no_barrier_fetch_add(&cc->things_queued_ever, 1);
+
+  GPR_TIMER_END("cq_end_op_for_next", 0);
+
+  GRPC_ERROR_UNREF(error);
+}
+
+/* Queue a GRPC_OP_COMPLETED operation to a completion queue (with a
+ * completion
+ * type of GRPC_CQ_PLUCK) */
+static void cq_end_op_for_pluck(grpc_exec_ctx *exec_ctx,
+                                grpc_completion_queue *cq, void *tag,
+                                grpc_error *error,
+                                void (*done)(grpc_exec_ctx *exec_ctx,
+                                             void *done_arg,
+                                             grpc_cq_completion *storage),
+                                void *done_arg, grpc_cq_completion *storage) {
+  cq_pluck_data *cqd = DATA_FROM_CQ(cq);
+  int is_success = (error == GRPC_ERROR_NONE);
+
+  GPR_TIMER_BEGIN("cq_end_op_for_pluck", 0);
+
+  if (GRPC_TRACER_ON(grpc_api_trace) ||
+      (GRPC_TRACER_ON(grpc_trace_operation_failures) &&
+       error != GRPC_ERROR_NONE)) {
+    const char *errmsg = grpc_error_string(error);
+    GRPC_API_TRACE(
+        "cq_end_op_for_pluck(exec_ctx=%p, cq=%p, tag=%p, error=%s, "
+        "done=%p, done_arg=%p, storage=%p)",
+        7, (exec_ctx, cq, tag, errmsg, done, done_arg, storage));
+    if (GRPC_TRACER_ON(grpc_trace_operation_failures) &&
+        error != GRPC_ERROR_NONE) {
+      gpr_log(GPR_ERROR, "Operation failed: tag=%p, error=%s", tag, errmsg);
+    }
+  }
+
+  storage->tag = tag;
+  storage->done = done;
+  storage->done_arg = done_arg;
+  storage->next = ((uintptr_t)&cqd->completed_head) | ((uintptr_t)(is_success));
+
+  gpr_mu_lock(cq->mu);
+  cq_check_tag(cq, tag, false); /* Used in debug builds only */
+
+  /* Add to the list of completions */
+  gpr_atm_no_barrier_fetch_add(&cqd->things_queued_ever, 1);
+  cqd->completed_tail->next =
+      ((uintptr_t)storage) | (1u & (uintptr_t)cqd->completed_tail->next);
+  cqd->completed_tail = storage;
+
+  int shutdown = gpr_unref(&cqd->pending_events);
   if (!shutdown) {
-    cc->completed_tail->next =
-        ((uintptr_t)storage) | (1u & (uintptr_t)cc->completed_tail->next);
-    cc->completed_tail = storage;
-    pluck_worker = NULL;
-    for (i = 0; i < cc->num_pluckers; i++) {
-      if (cc->pluckers[i].tag == tag) {
-        pluck_worker = *cc->pluckers[i].worker;
+    grpc_pollset_worker *pluck_worker = NULL;
+    for (int i = 0; i < cqd->num_pluckers; i++) {
+      if (cqd->pluckers[i].tag == tag) {
+        pluck_worker = *cqd->pluckers[i].worker;
         break;
       }
     }
+
     grpc_error *kick_error =
-        cc->poller_vtable->kick(POLLSET_FROM_CQ(cc), pluck_worker);
-    gpr_mu_unlock(cc->mu);
+        cq->poller_vtable->kick(POLLSET_FROM_CQ(cq), pluck_worker);
+
+    gpr_mu_unlock(cq->mu);
+
     if (kick_error != GRPC_ERROR_NONE) {
       const char *msg = grpc_error_string(kick_error);
       gpr_log(GPR_ERROR, "Kick failed: %s", msg);
@@ -435,22 +719,23 @@ void grpc_cq_end_op(grpc_exec_ctx *exec_ctx, grpc_completion_queue *cc,
       GRPC_ERROR_UNREF(kick_error);
     }
   } else {
-    cc->completed_tail->next =
-        ((uintptr_t)storage) | (1u & (uintptr_t)cc->completed_tail->next);
-    cc->completed_tail = storage;
-    GPR_ASSERT(!cc->shutdown);
-    GPR_ASSERT(cc->shutdown_called);
-    cc->shutdown = 1;
-    cc->poller_vtable->shutdown(exec_ctx, POLLSET_FROM_CQ(cc),
-                                &cc->pollset_shutdown_done);
-    gpr_mu_unlock(cc->mu);
+    cq_finish_shutdown_pluck(exec_ctx, cq);
+    gpr_mu_unlock(cq->mu);
   }
 
-  GPR_TIMER_END("grpc_cq_end_op", 0);
+  GPR_TIMER_END("cq_end_op_for_pluck", 0);
 
   GRPC_ERROR_UNREF(error);
 }
 
+void grpc_cq_end_op(grpc_exec_ctx *exec_ctx, grpc_completion_queue *cq,
+                    void *tag, grpc_error *error,
+                    void (*done)(grpc_exec_ctx *exec_ctx, void *done_arg,
+                                 grpc_cq_completion *storage),
+                    void *done_arg, grpc_cq_completion *storage) {
+  cq->vtable->end_op(exec_ctx, cq, tag, error, done, done_arg, storage);
+}
+
 typedef struct {
   gpr_atm last_seen_things_queued_ever;
   grpc_completion_queue *cq;
@@ -463,82 +748,78 @@ typedef struct {
 static bool cq_is_next_finished(grpc_exec_ctx *exec_ctx, void *arg) {
   cq_is_finished_arg *a = arg;
   grpc_completion_queue *cq = a->cq;
+  cq_next_data *cqd = DATA_FROM_CQ(cq);
   GPR_ASSERT(a->stolen_completion == NULL);
+
   gpr_atm current_last_seen_things_queued_ever =
-      gpr_atm_no_barrier_load(&cq->things_queued_ever);
+      gpr_atm_no_barrier_load(&cqd->things_queued_ever);
+
   if (current_last_seen_things_queued_ever != a->last_seen_things_queued_ever) {
-    gpr_mu_lock(cq->mu);
     a->last_seen_things_queued_ever =
-        gpr_atm_no_barrier_load(&cq->things_queued_ever);
-    if (cq->completed_tail != &cq->completed_head) {
-      a->stolen_completion = (grpc_cq_completion *)cq->completed_head.next;
-      cq->completed_head.next = a->stolen_completion->next & ~(uintptr_t)1;
-      if (a->stolen_completion == cq->completed_tail) {
-        cq->completed_tail = &cq->completed_head;
-      }
-      gpr_mu_unlock(cq->mu);
+        gpr_atm_no_barrier_load(&cqd->things_queued_ever);
+
+    /* Pop a cq_completion from the queue. Returns NULL if the queue is empty
+     * might return NULL in some cases even if the queue is not empty; but
+     * that
+     * is ok and doesn't affect correctness. Might effect the tail latencies a
+     * bit) */
+    a->stolen_completion = cq_event_queue_pop(&cqd->queue);
+    if (a->stolen_completion != NULL) {
       return true;
     }
-    gpr_mu_unlock(cq->mu);
   }
   return !a->first_loop && a->deadline < grpc_exec_ctx_now(exec_ctx);
 }
 
 #ifndef NDEBUG
-static void dump_pending_tags(grpc_completion_queue *cc) {
+static void dump_pending_tags(grpc_completion_queue *cq) {
   if (!GRPC_TRACER_ON(grpc_trace_pending_tags)) return;
 
   gpr_strvec v;
   gpr_strvec_init(&v);
   gpr_strvec_add(&v, gpr_strdup("PENDING TAGS:"));
-  gpr_mu_lock(cc->mu);
-  for (size_t i = 0; i < cc->outstanding_tag_count; i++) {
+  gpr_mu_lock(cq->mu);
+  for (size_t i = 0; i < cq->outstanding_tag_count; i++) {
     char *s;
-    gpr_asprintf(&s, " %p", cc->outstanding_tags[i]);
+    gpr_asprintf(&s, " %p", cq->outstanding_tags[i]);
     gpr_strvec_add(&v, s);
   }
-  gpr_mu_unlock(cc->mu);
+  gpr_mu_unlock(cq->mu);
   char *out = gpr_strvec_flatten(&v, NULL);
   gpr_strvec_destroy(&v);
   gpr_log(GPR_DEBUG, "%s", out);
   gpr_free(out);
 }
 #else
-static void dump_pending_tags(grpc_completion_queue *cc) {}
+static void dump_pending_tags(grpc_completion_queue *cq) {}
 #endif
 
-grpc_event grpc_completion_queue_next(grpc_completion_queue *cc,
-                                      gpr_timespec deadline, void *reserved) {
+static grpc_event cq_next(grpc_completion_queue *cq, gpr_timespec deadline,
+                          void *reserved) {
   grpc_event ret;
-
-  if (cc->completion_type != GRPC_CQ_NEXT) {
-    gpr_log(GPR_ERROR,
-            "grpc_completion_queue_next() cannot be called on this completion "
-            "queue since its completion type is not GRPC_CQ_NEXT");
-    abort();
-  }
+  cq_next_data *cqd = DATA_FROM_CQ(cq);
 
   GPR_TIMER_BEGIN("grpc_completion_queue_next", 0);
 
   GRPC_API_TRACE(
       "grpc_completion_queue_next("
-      "cc=%p, "
+      "cq=%p, "
       "deadline=gpr_timespec { tv_sec: %" PRId64
       ", tv_nsec: %d, clock_type: %d }, "
       "reserved=%p)",
-      5, (cc, deadline.tv_sec, deadline.tv_nsec, (int)deadline.clock_type,
+      5, (cq, deadline.tv_sec, deadline.tv_nsec, (int)deadline.clock_type,
           reserved));
   GPR_ASSERT(!reserved);
 
-  dump_pending_tags(cc);
+  dump_pending_tags(cq);
+
+  GRPC_CQ_INTERNAL_REF(cq, "next");
 
-  GRPC_CQ_INTERNAL_REF(cc, "next");
-  gpr_mu_lock(cc->mu);
   cq_is_finished_arg is_finished_arg = {
       .last_seen_things_queued_ever =
-          gpr_atm_no_barrier_load(&cc->things_queued_ever),
-      .cq = cc,
-      .deadline = 0, /* set below */
+          gpr_atm_no_barrier_load(&cqd->things_queued_ever),
+      .cq = cq,
+      .deadline = 0,
       .stolen_completion = NULL,
       .tag = NULL,
       .first_loop = true};
@@ -547,8 +828,9 @@ grpc_event grpc_completion_queue_next(grpc_completion_queue *cc,
   grpc_millis deadline_millis = is_finished_arg.deadline =
       grpc_timespec_to_millis(&exec_ctx, deadline);
   for (;;) {
+    grpc_millis iteration_deadline = deadline_millis;
+
     if (is_finished_arg.stolen_completion != NULL) {
-      gpr_mu_unlock(cc->mu);
       grpc_cq_completion *c = is_finished_arg.stolen_completion;
       is_finished_arg.stolen_completion = NULL;
       ret.type = GRPC_OP_COMPLETE;
@@ -557,76 +839,152 @@ grpc_event grpc_completion_queue_next(grpc_completion_queue *cc,
       c->done(&exec_ctx, c->done_arg, c);
       break;
     }
-    if (cc->completed_tail != &cc->completed_head) {
-      grpc_cq_completion *c = (grpc_cq_completion *)cc->completed_head.next;
-      cc->completed_head.next = c->next & ~(uintptr_t)1;
-      if (c == cc->completed_tail) {
-        cc->completed_tail = &cc->completed_head;
-      }
-      gpr_mu_unlock(cc->mu);
+
+    grpc_cq_completion *c = cq_event_queue_pop(&cqd->queue);
+
+    if (c != NULL) {
       ret.type = GRPC_OP_COMPLETE;
       ret.success = c->next & 1u;
       ret.tag = c->tag;
       c->done(&exec_ctx, c->done_arg, c);
       break;
+    } else {
+      /* If c == NULL it means either the queue is empty OR in an transient
+         inconsistent state. If it is the latter, we shold do a 0-timeout poll
+         so that the thread comes back quickly from poll to make a second
+         attempt at popping. Not doing this can potentially deadlock this
+         thread
+         forever (if the deadline is infinity) */
+      if (cq_event_queue_num_items(&cqd->queue) > 0) {
+        iteration_deadline = 0;
+      }
     }
-    if (cc->shutdown) {
-      gpr_mu_unlock(cc->mu);
+
+    if (gpr_atm_no_barrier_load(&cqd->pending_events) == 0) {
+      /* Before returning, check if the queue has any items left over (since
+         gpr_mpscq_pop() can sometimes return NULL even if the queue is not
+         empty. If so, keep retrying but do not return GRPC_QUEUE_SHUTDOWN */
+      if (cq_event_queue_num_items(&cqd->queue) > 0) {
+        /* Go to the beginning of the loop. No point doing a poll because
+           (cq->shutdown == true) is only possible when there is no pending
+           work
+           (i.e cq->pending_events == 0) and any outstanding
+           grpc_cq_completion
+           events are already queued on this cq */
+        continue;
+      }
+
       memset(&ret, 0, sizeof(ret));
       ret.type = GRPC_QUEUE_SHUTDOWN;
       break;
     }
+
     if (!is_finished_arg.first_loop &&
         grpc_exec_ctx_now(&exec_ctx) >= deadline_millis) {
-      gpr_mu_unlock(cc->mu);
       memset(&ret, 0, sizeof(ret));
       ret.type = GRPC_QUEUE_TIMEOUT;
-      dump_pending_tags(cc);
+      dump_pending_tags(cq);
       break;
     }
-    grpc_error *err = cc->poller_vtable->work(&exec_ctx, POLLSET_FROM_CQ(cc),
-                                              NULL, deadline_millis);
+
+    /* The main polling work happens in grpc_pollset_work */
+    gpr_mu_lock(cq->mu);
+    cq->num_polls++;
+    grpc_error *err = cq->poller_vtable->work(&exec_ctx, POLLSET_FROM_CQ(cq),
+                                              NULL, iteration_deadline);
+    gpr_mu_unlock(cq->mu);
+
     if (err != GRPC_ERROR_NONE) {
-      gpr_mu_unlock(cc->mu);
       const char *msg = grpc_error_string(err);
       gpr_log(GPR_ERROR, "Completion queue next failed: %s", msg);
 
       GRPC_ERROR_UNREF(err);
       memset(&ret, 0, sizeof(ret));
       ret.type = GRPC_QUEUE_TIMEOUT;
-      dump_pending_tags(cc);
+      dump_pending_tags(cq);
       break;
     }
     is_finished_arg.first_loop = false;
   }
-  GRPC_SURFACE_TRACE_RETURNED_EVENT(cc, &ret);
-  GRPC_CQ_INTERNAL_UNREF(&exec_ctx, cc, "next");
+
+  GRPC_SURFACE_TRACE_RETURNED_EVENT(cq, &ret);
+  GRPC_CQ_INTERNAL_UNREF(&exec_ctx, cq, "next");
   grpc_exec_ctx_finish(&exec_ctx);
   GPR_ASSERT(is_finished_arg.stolen_completion == NULL);
 
+  if (cq_event_queue_num_items(&cqd->queue) > 0 &&
+      gpr_atm_no_barrier_load(&cqd->pending_events) > 0) {
+    gpr_mu_lock(cq->mu);
+    cq->poller_vtable->kick(POLLSET_FROM_CQ(cq), NULL);
+    gpr_mu_unlock(cq->mu);
+  }
+
   GPR_TIMER_END("grpc_completion_queue_next", 0);
 
   return ret;
 }
 
-static int add_plucker(grpc_completion_queue *cc, void *tag,
+/* Finishes the completion queue shutdown. This means that there are no more
+   completion events / tags expected from the completion queue
+   - Must be called under completion queue lock
+   - Must be called only once in completion queue's lifetime
+   - grpc_completion_queue_shutdown() MUST have been called before calling
+   this function */
+static void cq_finish_shutdown_next(grpc_exec_ctx *exec_ctx,
+                                    grpc_completion_queue *cq) {
+  cq_next_data *cqd = DATA_FROM_CQ(cq);
+
+  GPR_ASSERT(cqd->shutdown_called);
+  GPR_ASSERT(gpr_atm_no_barrier_load(&cqd->pending_events) == 0);
+
+  cq->poller_vtable->shutdown(exec_ctx, POLLSET_FROM_CQ(cq),
+                              &cq->pollset_shutdown_done);
+}
+
+static void cq_shutdown_next(grpc_exec_ctx *exec_ctx,
+                             grpc_completion_queue *cq) {
+  cq_next_data *cqd = DATA_FROM_CQ(cq);
+
+  GRPC_CQ_INTERNAL_REF(cq, "shutting_down");
+  gpr_mu_lock(cq->mu);
+  if (cqd->shutdown_called) {
+    gpr_mu_unlock(cq->mu);
+    GRPC_CQ_INTERNAL_UNREF(exec_ctx, cq, "shutting_down");
+    GPR_TIMER_END("grpc_completion_queue_shutdown", 0);
+    return;
+  }
+  cqd->shutdown_called = 1;
+  if (gpr_atm_full_fetch_add(&cqd->pending_events, -1) == 1) {
+    cq_finish_shutdown_next(exec_ctx, cq);
+  }
+  gpr_mu_unlock(cq->mu);
+  GRPC_CQ_INTERNAL_UNREF(exec_ctx, cq, "shutting_down");
+}
+
+grpc_event grpc_completion_queue_next(grpc_completion_queue *cq,
+                                      gpr_timespec deadline, void *reserved) {
+  return cq->vtable->next(cq, deadline, reserved);
+}
+
+static int add_plucker(grpc_completion_queue *cq, void *tag,
                        grpc_pollset_worker **worker) {
-  if (cc->num_pluckers == GRPC_MAX_COMPLETION_QUEUE_PLUCKERS) {
+  cq_pluck_data *cqd = DATA_FROM_CQ(cq);
+  if (cqd->num_pluckers == GRPC_MAX_COMPLETION_QUEUE_PLUCKERS) {
     return 0;
   }
-  cc->pluckers[cc->num_pluckers].tag = tag;
-  cc->pluckers[cc->num_pluckers].worker = worker;
-  cc->num_pluckers++;
+  cqd->pluckers[cqd->num_pluckers].tag = tag;
+  cqd->pluckers[cqd->num_pluckers].worker = worker;
+  cqd->num_pluckers++;
   return 1;
 }
 
-static void del_plucker(grpc_completion_queue *cc, void *tag,
+static void del_plucker(grpc_completion_queue *cq, void *tag,
                         grpc_pollset_worker **worker) {
-  int i;
-  for (i = 0; i < cc->num_pluckers; i++) {
-    if (cc->pluckers[i].tag == tag && cc->pluckers[i].worker == worker) {
-      cc->num_pluckers--;
-      GPR_SWAP(plucker, cc->pluckers[i], cc->pluckers[cc->num_pluckers]);
+  cq_pluck_data *cqd = DATA_FROM_CQ(cq);
+  for (int i = 0; i < cqd->num_pluckers; i++) {
+    if (cqd->pluckers[i].tag == tag && cqd->pluckers[i].worker == worker) {
+      cqd->num_pluckers--;
+      GPR_SWAP(plucker, cqd->pluckers[i], cqd->pluckers[cqd->num_pluckers]);
       return;
     }
   }
@@ -636,21 +994,23 @@ static void del_plucker(grpc_completion_queue *cc, void *tag,
 static bool cq_is_pluck_finished(grpc_exec_ctx *exec_ctx, void *arg) {
   cq_is_finished_arg *a = arg;
   grpc_completion_queue *cq = a->cq;
+  cq_pluck_data *cqd = DATA_FROM_CQ(cq);
+
   GPR_ASSERT(a->stolen_completion == NULL);
   gpr_atm current_last_seen_things_queued_ever =
-      gpr_atm_no_barrier_load(&cq->things_queued_ever);
+      gpr_atm_no_barrier_load(&cqd->things_queued_ever);
   if (current_last_seen_things_queued_ever != a->last_seen_things_queued_ever) {
     gpr_mu_lock(cq->mu);
     a->last_seen_things_queued_ever =
-        gpr_atm_no_barrier_load(&cq->things_queued_ever);
+        gpr_atm_no_barrier_load(&cqd->things_queued_ever);
     grpc_cq_completion *c;
-    grpc_cq_completion *prev = &cq->completed_head;
+    grpc_cq_completion *prev = &cqd->completed_head;
     while ((c = (grpc_cq_completion *)(prev->next & ~(uintptr_t)1)) !=
-           &cq->completed_head) {
+           &cqd->completed_head) {
       if (c->tag == a->tag) {
         prev->next = (prev->next & (uintptr_t)1) | (c->next & ~(uintptr_t)1);
-        if (c == cq->completed_tail) {
-          cq->completed_tail = prev;
+        if (c == cqd->completed_tail) {
+          cqd->completed_tail = prev;
         }
         gpr_mu_unlock(cq->mu);
         a->stolen_completion = c;
@@ -663,43 +1023,39 @@ static bool cq_is_pluck_finished(grpc_exec_ctx *exec_ctx, void *arg) {
   return !a->first_loop && a->deadline < grpc_exec_ctx_now(exec_ctx);
 }
 
-grpc_event grpc_completion_queue_pluck(grpc_completion_queue *cc, void *tag,
-                                       gpr_timespec deadline, void *reserved) {
+static grpc_event cq_pluck(grpc_completion_queue *cq, void *tag,
+                           gpr_timespec deadline, void *reserved) {
   grpc_event ret;
   grpc_cq_completion *c;
   grpc_cq_completion *prev;
   grpc_pollset_worker *worker = NULL;
+  cq_pluck_data *cqd = DATA_FROM_CQ(cq);
 
   GPR_TIMER_BEGIN("grpc_completion_queue_pluck", 0);
 
-  if (cc->completion_type != GRPC_CQ_PLUCK) {
-    gpr_log(GPR_ERROR,
-            "grpc_completion_queue_pluck() cannot be called on this completion "
-            "queue since its completion type is not GRPC_CQ_PLUCK");
-    abort();
-  }
-
   if (GRPC_TRACER_ON(grpc_cq_pluck_trace)) {
     GRPC_API_TRACE(
         "grpc_completion_queue_pluck("
-        "cc=%p, tag=%p, "
+        "cq=%p, tag=%p, "
         "deadline=gpr_timespec { tv_sec: %" PRId64
         ", tv_nsec: %d, clock_type: %d }, "
         "reserved=%p)",
-        6, (cc, tag, deadline.tv_sec, deadline.tv_nsec,
+        6, (cq, tag, deadline.tv_sec, deadline.tv_nsec,
             (int)deadline.clock_type, reserved));
   }
   GPR_ASSERT(!reserved);
 
-  dump_pending_tags(cc);
+  dump_pending_tags(cq);
+
+  deadline = gpr_convert_clock_type(deadline, GPR_CLOCK_MONOTONIC);
 
-  GRPC_CQ_INTERNAL_REF(cc, "pluck");
-  gpr_mu_lock(cc->mu);
+  GRPC_CQ_INTERNAL_REF(cq, "pluck");
+  gpr_mu_lock(cq->mu);
   cq_is_finished_arg is_finished_arg = {
       .last_seen_things_queued_ever =
-          gpr_atm_no_barrier_load(&cc->things_queued_ever),
-      .cq = cc,
-      .deadline = 0, /* set below */
+          gpr_atm_no_barrier_load(&cqd->things_queued_ever),
+      .cq = cq,
+      .deadline = 0,
       .stolen_completion = NULL,
       .tag = tag,
       .first_loop = true};
@@ -709,7 +1065,7 @@ grpc_event grpc_completion_queue_pluck(grpc_completion_queue *cc, void *tag,
       grpc_timespec_to_millis(&exec_ctx, deadline);
   for (;;) {
     if (is_finished_arg.stolen_completion != NULL) {
-      gpr_mu_unlock(cc->mu);
+      gpr_mu_unlock(cq->mu);
       c = is_finished_arg.stolen_completion;
       is_finished_arg.stolen_completion = NULL;
       ret.type = GRPC_OP_COMPLETE;
@@ -718,15 +1074,15 @@ grpc_event grpc_completion_queue_pluck(grpc_completion_queue *cc, void *tag,
       c->done(&exec_ctx, c->done_arg, c);
       break;
     }
-    prev = &cc->completed_head;
+    prev = &cqd->completed_head;
     while ((c = (grpc_cq_completion *)(prev->next & ~(uintptr_t)1)) !=
-           &cc->completed_head) {
+           &cqd->completed_head) {
       if (c->tag == tag) {
         prev->next = (prev->next & (uintptr_t)1) | (c->next & ~(uintptr_t)1);
-        if (c == cc->completed_tail) {
-          cc->completed_tail = prev;
+        if (c == cqd->completed_tail) {
+          cqd->completed_tail = prev;
         }
-        gpr_mu_unlock(cc->mu);
+        gpr_mu_unlock(cq->mu);
         ret.type = GRPC_OP_COMPLETE;
         ret.success = c->next & 1u;
         ret.tag = c->tag;
@@ -735,53 +1091,53 @@ grpc_event grpc_completion_queue_pluck(grpc_completion_queue *cc, void *tag,
       }
       prev = c;
     }
-    if (cc->shutdown) {
-      gpr_mu_unlock(cc->mu);
+    if (gpr_atm_no_barrier_load(&cqd->shutdown)) {
+      gpr_mu_unlock(cq->mu);
       memset(&ret, 0, sizeof(ret));
       ret.type = GRPC_QUEUE_SHUTDOWN;
       break;
     }
-    if (!add_plucker(cc, tag, &worker)) {
+    if (!add_plucker(cq, tag, &worker)) {
       gpr_log(GPR_DEBUG,
               "Too many outstanding grpc_completion_queue_pluck calls: maximum "
               "is %d",
               GRPC_MAX_COMPLETION_QUEUE_PLUCKERS);
-      gpr_mu_unlock(cc->mu);
+      gpr_mu_unlock(cq->mu);
       memset(&ret, 0, sizeof(ret));
       /* TODO(ctiller): should we use a different result here */
       ret.type = GRPC_QUEUE_TIMEOUT;
-      dump_pending_tags(cc);
+      dump_pending_tags(cq);
       break;
     }
     if (!is_finished_arg.first_loop &&
         grpc_exec_ctx_now(&exec_ctx) >= deadline_millis) {
-      del_plucker(cc, tag, &worker);
-      gpr_mu_unlock(cc->mu);
+      del_plucker(cq, tag, &worker);
+      gpr_mu_unlock(cq->mu);
       memset(&ret, 0, sizeof(ret));
       ret.type = GRPC_QUEUE_TIMEOUT;
-      dump_pending_tags(cc);
+      dump_pending_tags(cq);
       break;
     }
-    grpc_error *err = cc->poller_vtable->work(&exec_ctx, POLLSET_FROM_CQ(cc),
+    grpc_error *err = cq->poller_vtable->work(&exec_ctx, POLLSET_FROM_CQ(cq),
                                               &worker, deadline_millis);
     if (err != GRPC_ERROR_NONE) {
-      del_plucker(cc, tag, &worker);
-      gpr_mu_unlock(cc->mu);
+      del_plucker(cq, tag, &worker);
+      gpr_mu_unlock(cq->mu);
       const char *msg = grpc_error_string(err);
-      gpr_log(GPR_ERROR, "Completion queue next failed: %s", msg);
+      gpr_log(GPR_ERROR, "Completion queue pluck failed: %s", msg);
 
       GRPC_ERROR_UNREF(err);
       memset(&ret, 0, sizeof(ret));
       ret.type = GRPC_QUEUE_TIMEOUT;
-      dump_pending_tags(cc);
+      dump_pending_tags(cq);
       break;
     }
     is_finished_arg.first_loop = false;
-    del_plucker(cc, tag, &worker);
+    del_plucker(cq, tag, &worker);
   }
 done:
-  GRPC_SURFACE_TRACE_RETURNED_EVENT(cc, &ret);
-  GRPC_CQ_INTERNAL_UNREF(&exec_ctx, cc, "pluck");
+  GRPC_SURFACE_TRACE_RETURNED_EVENT(cq, &ret);
+  GRPC_CQ_INTERNAL_UNREF(&exec_ctx, cq, "pluck");
   grpc_exec_ctx_finish(&exec_ctx);
   GPR_ASSERT(is_finished_arg.stolen_completion == NULL);
 
@@ -790,66 +1146,66 @@ done:
   return ret;
 }
 
-/* Shutdown simply drops a ref that we reserved at creation time; if we drop
-   to zero here, then enter shutdown mode and wake up any waiters */
-void grpc_completion_queue_shutdown(grpc_completion_queue *cc) {
-  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
-  GPR_TIMER_BEGIN("grpc_completion_queue_shutdown", 0);
-  GRPC_API_TRACE("grpc_completion_queue_shutdown(cc=%p)", 1, (cc));
-  gpr_mu_lock(cc->mu);
-  if (cc->shutdown_called) {
-    gpr_mu_unlock(cc->mu);
+grpc_event grpc_completion_queue_pluck(grpc_completion_queue *cq, void *tag,
+                                       gpr_timespec deadline, void *reserved) {
+  return cq->vtable->pluck(cq, tag, deadline, reserved);
+}
+
+static void cq_finish_shutdown_pluck(grpc_exec_ctx *exec_ctx,
+                                     grpc_completion_queue *cq) {
+  cq_pluck_data *cqd = DATA_FROM_CQ(cq);
+
+  GPR_ASSERT(cqd->shutdown_called);
+  GPR_ASSERT(!gpr_atm_no_barrier_load(&cqd->shutdown));
+  gpr_atm_no_barrier_store(&cqd->shutdown, 1);
+
+  cq->poller_vtable->shutdown(exec_ctx, POLLSET_FROM_CQ(cq),
+                              &cq->pollset_shutdown_done);
+}
+
+static void cq_shutdown_pluck(grpc_exec_ctx *exec_ctx,
+                              grpc_completion_queue *cq) {
+  cq_pluck_data *cqd = DATA_FROM_CQ(cq);
+
+  gpr_mu_lock(cq->mu);
+  if (cqd->shutdown_called) {
+    gpr_mu_unlock(cq->mu);
     GPR_TIMER_END("grpc_completion_queue_shutdown", 0);
     return;
   }
-  cc->shutdown_called = 1;
-  if (gpr_unref(&cc->pending_events)) {
-    GPR_ASSERT(!cc->shutdown);
-    cc->shutdown = 1;
-    cc->poller_vtable->shutdown(&exec_ctx, POLLSET_FROM_CQ(cc),
-                                &cc->pollset_shutdown_done);
+  cqd->shutdown_called = 1;
+  if (gpr_unref(&cqd->pending_events)) {
+    cq_finish_shutdown_pluck(exec_ctx, cq);
   }
-  gpr_mu_unlock(cc->mu);
+  gpr_mu_unlock(cq->mu);
+}
+
+/* Shutdown simply drops a ref that we reserved at creation time; if we drop
+   to zero here, then enter shutdown mode and wake up any waiters */
+void grpc_completion_queue_shutdown(grpc_completion_queue *cq) {
+  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
+  GPR_TIMER_BEGIN("grpc_completion_queue_shutdown", 0);
+  GRPC_API_TRACE("grpc_completion_queue_shutdown(cq=%p)", 1, (cq));
+  cq->vtable->shutdown(&exec_ctx, cq);
   grpc_exec_ctx_finish(&exec_ctx);
   GPR_TIMER_END("grpc_completion_queue_shutdown", 0);
 }
 
-void grpc_completion_queue_destroy(grpc_completion_queue *cc) {
-  GRPC_API_TRACE("grpc_completion_queue_destroy(cc=%p)", 1, (cc));
+void grpc_completion_queue_destroy(grpc_completion_queue *cq) {
+  GRPC_API_TRACE("grpc_completion_queue_destroy(cq=%p)", 1, (cq));
   GPR_TIMER_BEGIN("grpc_completion_queue_destroy", 0);
-  grpc_completion_queue_shutdown(cc);
+  grpc_completion_queue_shutdown(cq);
+
   grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
-  GRPC_CQ_INTERNAL_UNREF(&exec_ctx, cc, "destroy");
+  GRPC_CQ_INTERNAL_UNREF(&exec_ctx, cq, "destroy");
   grpc_exec_ctx_finish(&exec_ctx);
   GPR_TIMER_END("grpc_completion_queue_destroy", 0);
 }
 
-grpc_pollset *grpc_cq_pollset(grpc_completion_queue *cc) {
-  return cc->poller_vtable->can_get_pollset ? POLLSET_FROM_CQ(cc) : NULL;
-}
-
-grpc_completion_queue *grpc_cq_from_pollset(grpc_pollset *ps) {
-  return CQ_FROM_POLLSET(ps);
-}
-
-void grpc_cq_mark_non_listening_server_cq(grpc_completion_queue *cc) {
-  /* TODO: sreek - use cc->polling_type field here and add a validation check
-     (i.e grpc_cq_mark_non_listening_server_cq can only be called on a cc whose
-     polling_type is set to GRPC_CQ_NON_LISTENING */
-  cc->is_non_listening_server_cq = 1;
-}
-
-bool grpc_cq_is_non_listening_server_cq(grpc_completion_queue *cc) {
-  /* TODO (sreek) - return (cc->polling_type == GRPC_CQ_NON_LISTENING) */
-  return (cc->is_non_listening_server_cq == 1);
-}
-
-void grpc_cq_mark_server_cq(grpc_completion_queue *cc) { cc->is_server_cq = 1; }
-
-bool grpc_cq_is_server_cq(grpc_completion_queue *cc) {
-  return cc->is_server_cq;
+grpc_pollset *grpc_cq_pollset(grpc_completion_queue *cq) {
+  return cq->poller_vtable->can_get_pollset ? POLLSET_FROM_CQ(cq) : NULL;
 }
 
-bool grpc_cq_can_listen(grpc_completion_queue *cc) {
-  return cc->poller_vtable->can_listen;
+bool grpc_cq_can_listen(grpc_completion_queue *cq) {
+  return cq->poller_vtable->can_listen;
 }
diff --git a/src/core/lib/surface/completion_queue.h b/src/core/lib/surface/completion_queue.h
index 8d9ce2ec02..af44482513 100644
--- a/src/core/lib/surface/completion_queue.h
+++ b/src/core/lib/surface/completion_queue.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015-2016, Google Inc.
- * All rights reserved.
+ * Copyright 2015-2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -45,11 +30,19 @@
 extern grpc_tracer_flag grpc_cq_pluck_trace;
 extern grpc_tracer_flag grpc_cq_event_timeout_trace;
 extern grpc_tracer_flag grpc_trace_operation_failures;
+
 #ifndef NDEBUG
 extern grpc_tracer_flag grpc_trace_pending_tags;
+extern grpc_tracer_flag grpc_trace_cq_refcount;
+#endif
+
+#ifdef __cplusplus
+extern "C" {
 #endif
 
 typedef struct grpc_cq_completion {
+  gpr_mpscq_node node;
+
   /** user supplied tag */
   void *tag;
   /** done callback - called when this queue element is no longer
@@ -61,9 +54,7 @@ typedef struct grpc_cq_completion {
   uintptr_t next;
 } grpc_cq_completion;
 
-//#define GRPC_CQ_REF_COUNT_DEBUG
-
-#ifdef GRPC_CQ_REF_COUNT_DEBUG
+#ifndef NDEBUG
 void grpc_cq_internal_ref(grpc_completion_queue *cc, const char *reason,
                           const char *file, int line);
 void grpc_cq_internal_unref(grpc_exec_ctx *exec_ctx, grpc_completion_queue *cc,
@@ -93,15 +84,18 @@ void grpc_cq_end_op(grpc_exec_ctx *exec_ctx, grpc_completion_queue *cc,
                     void *done_arg, grpc_cq_completion *storage);
 
 grpc_pollset *grpc_cq_pollset(grpc_completion_queue *cc);
-grpc_completion_queue *grpc_cq_from_pollset(grpc_pollset *ps);
 
-void grpc_cq_mark_server_cq(grpc_completion_queue *cc);
-bool grpc_cq_is_server_cq(grpc_completion_queue *cc);
 bool grpc_cq_can_listen(grpc_completion_queue *cc);
 
 grpc_cq_completion_type grpc_get_cq_completion_type(grpc_completion_queue *cc);
 
+int grpc_get_cq_poll_num(grpc_completion_queue *cc);
+
 grpc_completion_queue *grpc_completion_queue_create_internal(
     grpc_cq_completion_type completion_type, grpc_cq_polling_type polling_type);
 
+#ifdef __cplusplus
+}
+#endif
+
 #endif /* GRPC_CORE_LIB_SURFACE_COMPLETION_QUEUE_H */
diff --git a/src/core/lib/surface/completion_queue_factory.c b/src/core/lib/surface/completion_queue_factory.c
index d68b84eddd..aeecff5306 100644
--- a/src/core/lib/surface/completion_queue_factory.c
+++ b/src/core/lib/surface/completion_queue_factory.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2017, Google Inc.
- * All rights reserved.
+ * Copyright 2017 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/surface/completion_queue_factory.h b/src/core/lib/surface/completion_queue_factory.h
index 57e90b5090..89be8f8216 100644
--- a/src/core/lib/surface/completion_queue_factory.h
+++ b/src/core/lib/surface/completion_queue_factory.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2017, Google Inc.
- * All rights reserved.
+ * Copyright 2017 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/surface/event_string.c b/src/core/lib/surface/event_string.c
index 1abc6ebf8c..f236272e2a 100644
--- a/src/core/lib/surface/event_string.c
+++ b/src/core/lib/surface/event_string.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/surface/event_string.h b/src/core/lib/surface/event_string.h
index bc1464380d..f00efca7f3 100644
--- a/src/core/lib/surface/event_string.h
+++ b/src/core/lib/surface/event_string.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/surface/init.c b/src/core/lib/surface/init.c
index 6163776152..db111e597f 100644
--- a/src/core/lib/surface/init.c
+++ b/src/core/lib/surface/init.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -128,34 +113,37 @@ void grpc_init(void) {
   int i;
   gpr_once_init(&g_basic_init, do_basic_init);
 
+  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
   gpr_mu_lock(&g_init_mu);
   if (++g_initializations == 1) {
     gpr_time_init();
     grpc_slice_intern_init();
     grpc_mdctx_global_init();
     grpc_channel_init_init();
-    grpc_register_tracer("api", &grpc_api_trace);
-    grpc_register_tracer("channel", &grpc_trace_channel);
-    grpc_register_tracer("connectivity_state", &grpc_connectivity_state_trace);
-    grpc_register_tracer("channel_stack_builder",
-                         &grpc_trace_channel_stack_builder);
-    grpc_register_tracer("http1", &grpc_http1_trace);
-    grpc_register_tracer("queue_pluck", &grpc_cq_pluck_trace);
-    grpc_register_tracer("combiner", &grpc_combiner_trace);
-    grpc_register_tracer("server_channel", &grpc_server_channel_trace);
-    grpc_register_tracer("bdp_estimator", &grpc_bdp_estimator_trace);
-    // Default pluck trace to 1
-    grpc_register_tracer("queue_timeout", &grpc_cq_event_timeout_trace);
-    // Default timeout trace to 1
-    grpc_register_tracer("op_failure", &grpc_trace_operation_failures);
-    grpc_register_tracer("resource_quota", &grpc_resource_quota_trace);
-    grpc_register_tracer("call_error", &grpc_call_error_trace);
+    grpc_register_tracer(&grpc_api_trace);
+    grpc_register_tracer(&grpc_trace_channel);
+    grpc_register_tracer(&grpc_connectivity_state_trace);
+    grpc_register_tracer(&grpc_trace_channel_stack_builder);
+    grpc_register_tracer(&grpc_http1_trace);
+    grpc_register_tracer(&grpc_cq_pluck_trace);  // default on
+    grpc_register_tracer(&grpc_combiner_trace);
+    grpc_register_tracer(&grpc_server_channel_trace);
+    grpc_register_tracer(&grpc_bdp_estimator_trace);
+    grpc_register_tracer(&grpc_cq_event_timeout_trace);  // default on
+    grpc_register_tracer(&grpc_trace_operation_failures);
+    grpc_register_tracer(&grpc_resource_quota_trace);
+    grpc_register_tracer(&grpc_call_error_trace);
 #ifndef NDEBUG
-    grpc_register_tracer("pending_tags", &grpc_trace_pending_tags);
+    grpc_register_tracer(&grpc_trace_pending_tags);
+    grpc_register_tracer(&grpc_trace_cq_refcount);
+    grpc_register_tracer(&grpc_trace_closure);
+    grpc_register_tracer(&grpc_trace_error_refcount);
+    grpc_register_tracer(&grpc_trace_stream_refcount);
+    grpc_register_tracer(&grpc_trace_fd_refcount);
+    grpc_register_tracer(&grpc_trace_metadata);
 #endif
     grpc_security_pre_init();
-    grpc_iomgr_init();
-    grpc_executor_init();
+    grpc_iomgr_init(&exec_ctx);
     gpr_timers_global_init();
     grpc_handshaker_factory_registry_init();
     grpc_security_init();
@@ -171,19 +159,20 @@ void grpc_init(void) {
     grpc_tracer_init("GRPC_TRACE");
     /* no more changes to channel init pipelines */
     grpc_channel_init_finalize();
-    grpc_iomgr_start();
+    grpc_iomgr_start(&exec_ctx);
   }
   gpr_mu_unlock(&g_init_mu);
+  grpc_exec_ctx_finish(&exec_ctx);
   GRPC_API_TRACE("grpc_init(void)", 0, ());
 }
 
 void grpc_shutdown(void) {
   int i;
   GRPC_API_TRACE("grpc_shutdown(void)", 0, ());
-  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
+  grpc_exec_ctx exec_ctx =
+      GRPC_EXEC_CTX_INITIALIZER(0, grpc_never_ready_to_finish, NULL);
   gpr_mu_lock(&g_init_mu);
   if (--g_initializations == 0) {
-    grpc_executor_shutdown(&exec_ctx);
     grpc_iomgr_shutdown(&exec_ctx);
     gpr_timers_global_destroy();
     grpc_tracer_shutdown();
diff --git a/src/core/lib/surface/init.h b/src/core/lib/surface/init.h
index 3d1c528be0..9353208332 100644
--- a/src/core/lib/surface/init.h
+++ b/src/core/lib/surface/init.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/surface/init_secure.c b/src/core/lib/surface/init_secure.c
index 746134676f..2366c24910 100644
--- a/src/core/lib/surface/init_secure.c
+++ b/src/core/lib/surface/init_secure.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -47,9 +32,17 @@
 #include "src/core/lib/surface/channel_init.h"
 #include "src/core/tsi/transport_security_interface.h"
 
+#ifndef NDEBUG
+#include "src/core/lib/security/context/security_context.h"
+#endif
+
 void grpc_security_pre_init(void) {
-  grpc_register_tracer("secure_endpoint", &grpc_trace_secure_endpoint);
-  grpc_register_tracer("transport_security", &tsi_tracing_enabled);
+  grpc_register_tracer(&grpc_trace_secure_endpoint);
+  grpc_register_tracer(&tsi_tracing_enabled);
+#ifndef NDEBUG
+  grpc_register_tracer(&grpc_trace_auth_context_refcount);
+  grpc_register_tracer(&grpc_trace_security_connector_refcount);
+#endif
 }
 
 static bool maybe_prepend_client_auth_filter(
diff --git a/src/core/lib/surface/init_unsecure.c b/src/core/lib/surface/init_unsecure.c
index dbc9223ae0..b852cab985 100644
--- a/src/core/lib/surface/init_unsecure.c
+++ b/src/core/lib/surface/init_unsecure.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/surface/lame_client.cc b/src/core/lib/surface/lame_client.cc
index 88f4eaac08..a0791080a9 100644
--- a/src/core/lib/surface/lame_client.cc
+++ b/src/core/lib/surface/lame_client.cc
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -120,17 +105,17 @@ static void lame_start_transport_op(grpc_exec_ctx *exec_ctx,
   if (op->on_connectivity_state_change) {
     GPR_ASSERT(*op->connectivity_state != GRPC_CHANNEL_SHUTDOWN);
     *op->connectivity_state = GRPC_CHANNEL_SHUTDOWN;
-    grpc_closure_sched(exec_ctx, op->on_connectivity_state_change,
+    GRPC_CLOSURE_SCHED(exec_ctx, op->on_connectivity_state_change,
                        GRPC_ERROR_NONE);
   }
   if (op->send_ping != NULL) {
-    grpc_closure_sched(
+    GRPC_CLOSURE_SCHED(
         exec_ctx, op->send_ping,
         GRPC_ERROR_CREATE_FROM_STATIC_STRING("lame client channel"));
   }
   GRPC_ERROR_UNREF(op->disconnect_with_error);
   if (op->on_consumed != NULL) {
-    grpc_closure_sched(exec_ctx, op->on_consumed, GRPC_ERROR_NONE);
+    GRPC_CLOSURE_SCHED(exec_ctx, op->on_consumed, GRPC_ERROR_NONE);
   }
 }
 
@@ -143,7 +128,7 @@ static grpc_error *init_call_elem(grpc_exec_ctx *exec_ctx,
 static void destroy_call_elem(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
                               const grpc_call_final_info *final_info,
                               grpc_closure *then_schedule_closure) {
-  grpc_closure_sched(exec_ctx, then_schedule_closure, GRPC_ERROR_NONE);
+  GRPC_CLOSURE_SCHED(exec_ctx, then_schedule_closure, GRPC_ERROR_NONE);
 }
 
 static grpc_error *init_channel_elem(grpc_exec_ctx *exec_ctx,
diff --git a/src/core/lib/surface/lame_client.h b/src/core/lib/surface/lame_client.h
index 5f6ea34d4b..3ce353f101 100644
--- a/src/core/lib/surface/lame_client.h
+++ b/src/core/lib/surface/lame_client.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/surface/metadata_array.c b/src/core/lib/surface/metadata_array.c
index 6c2b750e1d..0afb8b4b87 100644
--- a/src/core/lib/surface/metadata_array.c
+++ b/src/core/lib/surface/metadata_array.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/surface/server.c b/src/core/lib/surface/server.c
index 560229e892..fce7f8dca1 100644
--- a/src/core/lib/surface/server.c
+++ b/src/core/lib/surface/server.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015-2016, Google Inc.
- * All rights reserved.
+ * Copyright 2015-2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -73,7 +58,8 @@ typedef struct registered_method registered_method;
 
 typedef enum { BATCH_CALL, REGISTERED_CALL } requested_call_type;
 
-grpc_tracer_flag grpc_server_channel_trace = GRPC_TRACER_INITIALIZER(false);
+grpc_tracer_flag grpc_server_channel_trace =
+    GRPC_TRACER_INITIALIZER(false, "server_channel");
 
 typedef struct requested_call {
   requested_call_type type;
@@ -287,7 +273,7 @@ static void shutdown_cleanup(grpc_exec_ctx *exec_ctx, void *arg,
 static void send_shutdown(grpc_exec_ctx *exec_ctx, grpc_channel *channel,
                           bool send_goaway, grpc_error *send_disconnect) {
   struct shutdown_cleanup_args *sc = gpr_malloc(sizeof(*sc));
-  grpc_closure_init(&sc->closure, shutdown_cleanup, sc,
+  GRPC_CLOSURE_INIT(&sc->closure, shutdown_cleanup, sc,
                     grpc_schedule_on_exec_ctx);
   grpc_transport_op *op = grpc_make_transport_op(&sc->closure);
   grpc_channel_element *elem;
@@ -356,11 +342,11 @@ static void request_matcher_zombify_all_pending_calls(grpc_exec_ctx *exec_ctx,
     gpr_mu_lock(&calld->mu_state);
     calld->state = ZOMBIED;
     gpr_mu_unlock(&calld->mu_state);
-    grpc_closure_init(
+    GRPC_CLOSURE_INIT(
         &calld->kill_zombie_closure, kill_zombie,
         grpc_call_stack_element(grpc_call_get_call_stack(calld->call), 0),
         grpc_schedule_on_exec_ctx);
-    grpc_closure_sched(exec_ctx, &calld->kill_zombie_closure, GRPC_ERROR_NONE);
+    GRPC_CLOSURE_SCHED(exec_ctx, &calld->kill_zombie_closure, GRPC_ERROR_NONE);
   }
 }
 
@@ -453,7 +439,7 @@ static void destroy_channel(grpc_exec_ctx *exec_ctx, channel_data *chand,
   orphan_channel(chand);
   server_ref(chand->server);
   maybe_finish_shutdown(exec_ctx, chand->server);
-  grpc_closure_init(&chand->finish_destroy_channel_closure,
+  GRPC_CLOSURE_INIT(&chand->finish_destroy_channel_closure,
                     finish_destroy_channel, chand, grpc_schedule_on_exec_ctx);
 
   if (GRPC_TRACER_ON(grpc_server_channel_trace) && error != GRPC_ERROR_NONE) {
@@ -510,6 +496,7 @@ static void publish_call(grpc_exec_ctx *exec_ctx, grpc_server *server,
       *rc->data.registered.deadline = calld->deadline;
       if (rc->data.registered.optional_payload) {
         *rc->data.registered.optional_payload = calld->payload;
+        calld->payload = NULL;
       }
       break;
     default:
@@ -536,11 +523,11 @@ static void publish_new_rpc(grpc_exec_ctx *exec_ctx, void *arg,
     gpr_mu_lock(&calld->mu_state);
     calld->state = ZOMBIED;
     gpr_mu_unlock(&calld->mu_state);
-    grpc_closure_init(
+    GRPC_CLOSURE_INIT(
         &calld->kill_zombie_closure, kill_zombie,
         grpc_call_stack_element(grpc_call_get_call_stack(calld->call), 0),
         grpc_schedule_on_exec_ctx);
-    grpc_closure_sched(exec_ctx, &calld->kill_zombie_closure,
+    GRPC_CLOSURE_SCHED(exec_ctx, &calld->kill_zombie_closure,
                        GRPC_ERROR_REF(error));
     return;
   }
@@ -585,9 +572,9 @@ static void finish_start_new_rpc(
     gpr_mu_lock(&calld->mu_state);
     calld->state = ZOMBIED;
     gpr_mu_unlock(&calld->mu_state);
-    grpc_closure_init(&calld->kill_zombie_closure, kill_zombie, elem,
+    GRPC_CLOSURE_INIT(&calld->kill_zombie_closure, kill_zombie, elem,
                       grpc_schedule_on_exec_ctx);
-    grpc_closure_sched(exec_ctx, &calld->kill_zombie_closure, GRPC_ERROR_NONE);
+    GRPC_CLOSURE_SCHED(exec_ctx, &calld->kill_zombie_closure, GRPC_ERROR_NONE);
     return;
   }
 
@@ -602,7 +589,7 @@ static void finish_start_new_rpc(
       memset(&op, 0, sizeof(op));
       op.op = GRPC_OP_RECV_MESSAGE;
       op.data.recv_message.recv_message = &calld->payload;
-      grpc_closure_init(&calld->publish, publish_new_rpc, elem,
+      GRPC_CLOSURE_INIT(&calld->publish, publish_new_rpc, elem,
                         grpc_schedule_on_exec_ctx);
       grpc_call_start_batch_and_execute(exec_ctx, calld->call, &op, 1,
                                         &calld->publish);
@@ -779,7 +766,7 @@ static void server_on_recv_initial_metadata(grpc_exec_ctx *exec_ctx, void *ptr,
     GRPC_ERROR_UNREF(src_error);
   }
 
-  grpc_closure_run(exec_ctx, calld->on_done_recv_initial_metadata, error);
+  GRPC_CLOSURE_RUN(exec_ctx, calld->on_done_recv_initial_metadata, error);
 }
 
 static void server_mutate_op(grpc_call_element *elem,
@@ -818,9 +805,9 @@ static void got_initial_metadata(grpc_exec_ctx *exec_ctx, void *ptr,
     if (calld->state == NOT_STARTED) {
       calld->state = ZOMBIED;
       gpr_mu_unlock(&calld->mu_state);
-      grpc_closure_init(&calld->kill_zombie_closure, kill_zombie, elem,
+      GRPC_CLOSURE_INIT(&calld->kill_zombie_closure, kill_zombie, elem,
                         grpc_schedule_on_exec_ctx);
-      grpc_closure_sched(exec_ctx, &calld->kill_zombie_closure,
+      GRPC_CLOSURE_SCHED(exec_ctx, &calld->kill_zombie_closure,
                          GRPC_ERROR_NONE);
     } else if (calld->state == PENDING) {
       calld->state = ZOMBIED;
@@ -858,7 +845,7 @@ static void accept_stream(grpc_exec_ctx *exec_ctx, void *cd,
   op.op = GRPC_OP_RECV_INITIAL_METADATA;
   op.data.recv_initial_metadata.recv_initial_metadata =
       &calld->initial_metadata;
-  grpc_closure_init(&calld->got_initial_metadata, got_initial_metadata, elem,
+  GRPC_CLOSURE_INIT(&calld->got_initial_metadata, got_initial_metadata, elem,
                     grpc_schedule_on_exec_ctx);
   grpc_call_start_batch_and_execute(exec_ctx, call, &op, 1,
                                     &calld->got_initial_metadata);
@@ -894,7 +881,7 @@ static grpc_error *init_call_elem(grpc_exec_ctx *exec_ctx,
   calld->call = grpc_call_from_top_element(elem);
   gpr_mu_init(&calld->mu_state);
 
-  grpc_closure_init(&calld->server_on_recv_initial_metadata,
+  GRPC_CLOSURE_INIT(&calld->server_on_recv_initial_metadata,
                     server_on_recv_initial_metadata, elem,
                     grpc_schedule_on_exec_ctx);
 
@@ -917,6 +904,7 @@ static void destroy_call_elem(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
     grpc_slice_unref_internal(exec_ctx, calld->path);
   }
   grpc_metadata_array_destroy(&calld->initial_metadata);
+  grpc_byte_buffer_destroy(calld->payload);
 
   gpr_mu_destroy(&calld->mu_state);
 
@@ -934,7 +922,7 @@ static grpc_error *init_channel_elem(grpc_exec_ctx *exec_ctx,
   chand->next = chand->prev = chand;
   chand->registered_methods = NULL;
   chand->connectivity_state = GRPC_CHANNEL_IDLE;
-  grpc_closure_init(&chand->channel_connectivity_changed,
+  GRPC_CLOSURE_INIT(&chand->channel_connectivity_changed,
                     channel_connectivity_changed, chand,
                     grpc_schedule_on_exec_ctx);
   return GRPC_ERROR_NONE;
@@ -988,8 +976,6 @@ static void register_completion_queue(grpc_server *server,
     if (server->cqs[i] == cq) return;
   }
 
-  grpc_cq_mark_server_cq(cq);
-
   GRPC_CQ_INTERNAL_REF(cq, "server");
   n = server->cq_count++;
   server->cqs = gpr_realloc(server->cqs,
@@ -1130,7 +1116,7 @@ void grpc_server_start(grpc_server *server) {
 
   server_ref(server);
   server->starting = true;
-  grpc_closure_sched(&exec_ctx, grpc_closure_create(start_listeners, server,
+  GRPC_CLOSURE_SCHED(&exec_ctx, GRPC_CLOSURE_CREATE(start_listeners, server,
                                                     grpc_executor_scheduler),
                      GRPC_ERROR_NONE);
 
@@ -1169,9 +1155,8 @@ void grpc_server_setup_transport(grpc_exec_ctx *exec_ctx, grpc_server *s,
   chand->channel = channel;
 
   size_t cq_idx;
-  grpc_completion_queue *accepting_cq = grpc_cq_from_pollset(accepting_pollset);
   for (cq_idx = 0; cq_idx < s->cq_count; cq_idx++) {
-    if (s->cqs[cq_idx] == accepting_cq) break;
+    if (grpc_cq_pollset(s->cqs[cq_idx]) == accepting_pollset) break;
   }
   if (cq_idx == s->cq_count) {
     /* completion queue not found: pick a random one to publish new calls to */
@@ -1310,7 +1295,7 @@ void grpc_server_shutdown_and_notify(grpc_server *server,
 
   /* Shutdown listeners */
   for (l = server->listeners; l; l = l->next) {
-    grpc_closure_init(&l->destroy_done, listener_destroy_done, server,
+    GRPC_CLOSURE_INIT(&l->destroy_done, listener_destroy_done, server,
                       grpc_schedule_on_exec_ctx);
     l->destroy(&exec_ctx, server, l->arg, &l->destroy_done);
   }
@@ -1416,11 +1401,11 @@ static grpc_call_error queue_call_request(grpc_exec_ctx *exec_ctx,
       gpr_mu_lock(&calld->mu_state);
       if (calld->state == ZOMBIED) {
         gpr_mu_unlock(&calld->mu_state);
-        grpc_closure_init(
+        GRPC_CLOSURE_INIT(
             &calld->kill_zombie_closure, kill_zombie,
             grpc_call_stack_element(grpc_call_get_call_stack(calld->call), 0),
             grpc_schedule_on_exec_ctx);
-        grpc_closure_sched(exec_ctx, &calld->kill_zombie_closure,
+        GRPC_CLOSURE_SCHED(exec_ctx, &calld->kill_zombie_closure,
                            GRPC_ERROR_NONE);
       } else {
         GPR_ASSERT(calld->state == PENDING);
diff --git a/src/core/lib/surface/server.h b/src/core/lib/surface/server.h
index cd2fca0fe0..dd5639d97a 100644
--- a/src/core/lib/surface/server.h
+++ b/src/core/lib/surface/server.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/surface/validate_metadata.c b/src/core/lib/surface/validate_metadata.c
index 6e76c4efe7..61209ae48d 100644
--- a/src/core/lib/surface/validate_metadata.c
+++ b/src/core/lib/surface/validate_metadata.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/surface/validate_metadata.h b/src/core/lib/surface/validate_metadata.h
index 2b800d25a4..de869d89b4 100644
--- a/src/core/lib/surface/validate_metadata.h
+++ b/src/core/lib/surface/validate_metadata.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2017, Google Inc.
- * All rights reserved.
+ * Copyright 2017 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/surface/version.c b/src/core/lib/surface/version.c
index cddc595e4c..8cef15da80 100644
--- a/src/core/lib/surface/version.c
+++ b/src/core/lib/surface/version.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/transport/bdp_estimator.c b/src/core/lib/transport/bdp_estimator.c
index da8019d98b..311ae6390d 100644
--- a/src/core/lib/transport/bdp_estimator.c
+++ b/src/core/lib/transport/bdp_estimator.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -38,7 +23,8 @@
 #include <grpc/support/log.h>
 #include <grpc/support/useful.h>
 
-grpc_tracer_flag grpc_bdp_estimator_trace = GRPC_TRACER_INITIALIZER(false);
+grpc_tracer_flag grpc_bdp_estimator_trace =
+    GRPC_TRACER_INITIALIZER(false, "bdp_estimator");
 
 void grpc_bdp_estimator_init(grpc_bdp_estimator *estimator, const char *name) {
   estimator->estimate = 65536;
@@ -53,6 +39,11 @@ bool grpc_bdp_estimator_get_estimate(grpc_bdp_estimator *estimator,
   return true;
 }
 
+bool grpc_bdp_estimator_get_bw(grpc_bdp_estimator *estimator, double *bw) {
+  *bw = estimator->bw_est;
+  return true;
+}
+
 bool grpc_bdp_estimator_add_incoming_bytes(grpc_bdp_estimator *estimator,
                                            int64_t num_bytes) {
   estimator->accumulator += num_bytes;
diff --git a/src/core/lib/transport/bdp_estimator.h b/src/core/lib/transport/bdp_estimator.h
index 135376edd7..a232d1f87f 100644
--- a/src/core/lib/transport/bdp_estimator.h
+++ b/src/core/lib/transport/bdp_estimator.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -64,6 +49,8 @@ void grpc_bdp_estimator_init(grpc_bdp_estimator *estimator, const char *name);
 // Returns true if a reasonable estimate could be obtained
 bool grpc_bdp_estimator_get_estimate(grpc_bdp_estimator *estimator,
                                      int64_t *estimate);
+// Returns true if a reasonable estimate could be obtained
+bool grpc_bdp_estimator_get_bw(grpc_bdp_estimator *estimator, double *bw);
 // Returns true if the user should schedule a ping
 bool grpc_bdp_estimator_add_incoming_bytes(grpc_bdp_estimator *estimator,
                                            int64_t num_bytes);
diff --git a/src/core/lib/transport/byte_stream.c b/src/core/lib/transport/byte_stream.c
index 5800c70ef4..3355814017 100644
--- a/src/core/lib/transport/byte_stream.c
+++ b/src/core/lib/transport/byte_stream.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/transport/byte_stream.h b/src/core/lib/transport/byte_stream.h
index 381c65fb04..f172296e4b 100644
--- a/src/core/lib/transport/byte_stream.h
+++ b/src/core/lib/transport/byte_stream.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/transport/connectivity_state.c b/src/core/lib/transport/connectivity_state.c
index e30cd523fa..73a9178ae2 100644
--- a/src/core/lib/transport/connectivity_state.c
+++ b/src/core/lib/transport/connectivity_state.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -39,7 +24,8 @@
 #include <grpc/support/log.h>
 #include <grpc/support/string_util.h>
 
-grpc_tracer_flag grpc_connectivity_state_trace = GRPC_TRACER_INITIALIZER(false);
+grpc_tracer_flag grpc_connectivity_state_trace =
+    GRPC_TRACER_INITIALIZER(false, "connectivity_state");
 
 const char *grpc_connectivity_state_name(grpc_connectivity_state state) {
   switch (state) {
@@ -82,7 +68,7 @@ void grpc_connectivity_state_destroy(grpc_exec_ctx *exec_ctx,
       error =
           GRPC_ERROR_CREATE_FROM_STATIC_STRING("Shutdown connectivity owner");
     }
-    grpc_closure_sched(exec_ctx, w->notify, error);
+    GRPC_CLOSURE_SCHED(exec_ctx, w->notify, error);
     gpr_free(w);
   }
   GRPC_ERROR_UNREF(tracker->current_error);
@@ -140,7 +126,7 @@ bool grpc_connectivity_state_notify_on_state_change(
   if (current == NULL) {
     grpc_connectivity_state_watcher *w = tracker->watchers;
     if (w != NULL && w->notify == notify) {
-      grpc_closure_sched(exec_ctx, notify, GRPC_ERROR_CANCELLED);
+      GRPC_CLOSURE_SCHED(exec_ctx, notify, GRPC_ERROR_CANCELLED);
       tracker->watchers = w->next;
       gpr_free(w);
       return false;
@@ -148,7 +134,7 @@ bool grpc_connectivity_state_notify_on_state_change(
     while (w != NULL) {
       grpc_connectivity_state_watcher *rm_candidate = w->next;
       if (rm_candidate != NULL && rm_candidate->notify == notify) {
-        grpc_closure_sched(exec_ctx, notify, GRPC_ERROR_CANCELLED);
+        GRPC_CLOSURE_SCHED(exec_ctx, notify, GRPC_ERROR_CANCELLED);
         w->next = w->next->next;
         gpr_free(rm_candidate);
         return false;
@@ -159,7 +145,7 @@ bool grpc_connectivity_state_notify_on_state_change(
   } else {
     if (cur != *current) {
       *current = cur;
-      grpc_closure_sched(exec_ctx, notify,
+      GRPC_CLOSURE_SCHED(exec_ctx, notify,
                          GRPC_ERROR_REF(tracker->current_error));
     } else {
       grpc_connectivity_state_watcher *w = gpr_malloc(sizeof(*w));
@@ -212,7 +198,7 @@ void grpc_connectivity_state_set(grpc_exec_ctx *exec_ctx,
       gpr_log(GPR_DEBUG, "NOTIFY: %p %s: %p", tracker, tracker->name,
               w->notify);
     }
-    grpc_closure_sched(exec_ctx, w->notify,
+    GRPC_CLOSURE_SCHED(exec_ctx, w->notify,
                        GRPC_ERROR_REF(tracker->current_error));
     gpr_free(w);
   }
diff --git a/src/core/lib/transport/connectivity_state.h b/src/core/lib/transport/connectivity_state.h
index cdc2930c11..2fece6cc21 100644
--- a/src/core/lib/transport/connectivity_state.h
+++ b/src/core/lib/transport/connectivity_state.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/transport/error_utils.c b/src/core/lib/transport/error_utils.c
index 4e70f8749d..5e3920b627 100644
--- a/src/core/lib/transport/error_utils.c
+++ b/src/core/lib/transport/error_utils.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/transport/error_utils.h b/src/core/lib/transport/error_utils.h
index 3b44466ab8..e530884215 100644
--- a/src/core/lib/transport/error_utils.h
+++ b/src/core/lib/transport/error_utils.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/transport/http2_errors.h b/src/core/lib/transport/http2_errors.h
index 330bc987f6..d412c5dffc 100644
--- a/src/core/lib/transport/http2_errors.h
+++ b/src/core/lib/transport/http2_errors.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/transport/metadata.c b/src/core/lib/transport/metadata.c
index f2417d8c4e..2fea366072 100644
--- a/src/core/lib/transport/metadata.c
+++ b/src/core/lib/transport/metadata.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -62,7 +47,9 @@
  * used to determine which kind of element a pointer refers to.
  */
 
-#ifdef GRPC_METADATA_REFCOUNT_DEBUG
+#ifndef NDEBUG
+grpc_tracer_flag grpc_trace_metadata =
+    GRPC_TRACER_INITIALIZER(false, "metadata");
 #define DEBUG_ARGS , const char *file, int line
 #define FWD_DEBUG_ARGS , file, line
 #define REF_MD_LOCKED(shard, s) ref_md_locked((shard), (s), __FILE__, __LINE__)
@@ -159,15 +146,17 @@ static int is_mdelem_static(grpc_mdelem e) {
 
 static void ref_md_locked(mdtab_shard *shard,
                           interned_metadata *md DEBUG_ARGS) {
-#ifdef GRPC_METADATA_REFCOUNT_DEBUG
-  char *key_str = grpc_slice_to_c_string(md->key);
-  char *value_str = grpc_slice_to_c_string(md->value);
-  gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
-          "ELM   REF:%p:%zu->%zu: '%s' = '%s'", (void *)md,
-          gpr_atm_no_barrier_load(&md->refcnt),
-          gpr_atm_no_barrier_load(&md->refcnt) + 1, key_str, value_str);
-  gpr_free(key_str);
-  gpr_free(value_str);
+#ifndef NDEBUG
+  if (GRPC_TRACER_ON(grpc_trace_metadata)) {
+    char *key_str = grpc_slice_to_c_string(md->key);
+    char *value_str = grpc_slice_to_c_string(md->value);
+    gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
+            "ELM   REF:%p:%" PRIdPTR "->%" PRIdPTR ": '%s' = '%s'", (void *)md,
+            gpr_atm_no_barrier_load(&md->refcnt),
+            gpr_atm_no_barrier_load(&md->refcnt) + 1, key_str, value_str);
+    gpr_free(key_str);
+    gpr_free(value_str);
+  }
 #endif
   if (0 == gpr_atm_no_barrier_fetch_add(&md->refcnt, 1)) {
     gpr_atm_no_barrier_fetch_add(&shard->free_estimate, -1);
@@ -258,13 +247,16 @@ grpc_mdelem grpc_mdelem_create(
     allocated->key = grpc_slice_ref_internal(key);
     allocated->value = grpc_slice_ref_internal(value);
     gpr_atm_rel_store(&allocated->refcnt, 1);
-#ifdef GRPC_METADATA_REFCOUNT_DEBUG
-    char *key_str = grpc_slice_to_c_string(allocated->key);
-    char *value_str = grpc_slice_to_c_string(allocated->value);
-    gpr_log(GPR_DEBUG, "ELM ALLOC:%p:%zu: '%s' = '%s'", (void *)allocated,
-            gpr_atm_no_barrier_load(&allocated->refcnt), key_str, value_str);
-    gpr_free(key_str);
-    gpr_free(value_str);
+#ifndef NDEBUG
+    if (GRPC_TRACER_ON(grpc_trace_metadata)) {
+      char *key_str = grpc_slice_to_c_string(allocated->key);
+      char *value_str = grpc_slice_to_c_string(allocated->value);
+      gpr_log(GPR_DEBUG, "ELM ALLOC:%p:%" PRIdPTR ": '%s' = '%s'",
+              (void *)allocated, gpr_atm_no_barrier_load(&allocated->refcnt),
+              key_str, value_str);
+      gpr_free(key_str);
+      gpr_free(value_str);
+    }
 #endif
     return GRPC_MAKE_MDELEM(allocated, GRPC_MDELEM_STORAGE_ALLOCATED);
   }
@@ -309,13 +301,15 @@ grpc_mdelem grpc_mdelem_create(
   md->bucket_next = shard->elems[idx];
   shard->elems[idx] = md;
   gpr_mu_init(&md->mu_user_data);
-#ifdef GRPC_METADATA_REFCOUNT_DEBUG
-  char *key_str = grpc_slice_to_c_string(md->key);
-  char *value_str = grpc_slice_to_c_string(md->value);
-  gpr_log(GPR_DEBUG, "ELM   NEW:%p:%zu: '%s' = '%s'", (void *)md,
-          gpr_atm_no_barrier_load(&md->refcnt), key_str, value_str);
-  gpr_free(key_str);
-  gpr_free(value_str);
+#ifndef NDEBUG
+  if (GRPC_TRACER_ON(grpc_trace_metadata)) {
+    char *key_str = grpc_slice_to_c_string(md->key);
+    char *value_str = grpc_slice_to_c_string(md->value);
+    gpr_log(GPR_DEBUG, "ELM   NEW:%p:%" PRIdPTR ": '%s' = '%s'", (void *)md,
+            gpr_atm_no_barrier_load(&md->refcnt), key_str, value_str);
+    gpr_free(key_str);
+    gpr_free(value_str);
+  }
 #endif
   shard->count++;
 
@@ -371,15 +365,17 @@ grpc_mdelem grpc_mdelem_ref(grpc_mdelem gmd DEBUG_ARGS) {
       break;
     case GRPC_MDELEM_STORAGE_INTERNED: {
       interned_metadata *md = (interned_metadata *)GRPC_MDELEM_DATA(gmd);
-#ifdef GRPC_METADATA_REFCOUNT_DEBUG
-      char *key_str = grpc_slice_to_c_string(md->key);
-      char *value_str = grpc_slice_to_c_string(md->value);
-      gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
-              "ELM   REF:%p:%zu->%zu: '%s' = '%s'", (void *)md,
-              gpr_atm_no_barrier_load(&md->refcnt),
-              gpr_atm_no_barrier_load(&md->refcnt) + 1, key_str, value_str);
-      gpr_free(key_str);
-      gpr_free(value_str);
+#ifndef NDEBUG
+      if (GRPC_TRACER_ON(grpc_trace_metadata)) {
+        char *key_str = grpc_slice_to_c_string(md->key);
+        char *value_str = grpc_slice_to_c_string(md->value);
+        gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
+                "ELM   REF:%p:%" PRIdPTR "->%" PRIdPTR ": '%s' = '%s'",
+                (void *)md, gpr_atm_no_barrier_load(&md->refcnt),
+                gpr_atm_no_barrier_load(&md->refcnt) + 1, key_str, value_str);
+        gpr_free(key_str);
+        gpr_free(value_str);
+      }
 #endif
       /* we can assume the ref count is >= 1 as the application is calling
          this function - meaning that no adjustment to mdtab_free is necessary,
@@ -391,15 +387,17 @@ grpc_mdelem grpc_mdelem_ref(grpc_mdelem gmd DEBUG_ARGS) {
     }
     case GRPC_MDELEM_STORAGE_ALLOCATED: {
       allocated_metadata *md = (allocated_metadata *)GRPC_MDELEM_DATA(gmd);
-#ifdef GRPC_METADATA_REFCOUNT_DEBUG
-      char *key_str = grpc_slice_to_c_string(md->key);
-      char *value_str = grpc_slice_to_c_string(md->value);
-      gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
-              "ELM   REF:%p:%zu->%zu: '%s' = '%s'", (void *)md,
-              gpr_atm_no_barrier_load(&md->refcnt),
-              gpr_atm_no_barrier_load(&md->refcnt) + 1, key_str, value_str);
-      gpr_free(key_str);
-      gpr_free(value_str);
+#ifndef NDEBUG
+      if (GRPC_TRACER_ON(grpc_trace_metadata)) {
+        char *key_str = grpc_slice_to_c_string(md->key);
+        char *value_str = grpc_slice_to_c_string(md->value);
+        gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
+                "ELM   REF:%p:%" PRIdPTR "->%" PRIdPTR ": '%s' = '%s'",
+                (void *)md, gpr_atm_no_barrier_load(&md->refcnt),
+                gpr_atm_no_barrier_load(&md->refcnt) + 1, key_str, value_str);
+        gpr_free(key_str);
+        gpr_free(value_str);
+      }
 #endif
       /* we can assume the ref count is >= 1 as the application is calling
          this function - meaning that no adjustment to mdtab_free is necessary,
@@ -419,15 +417,17 @@ void grpc_mdelem_unref(grpc_exec_ctx *exec_ctx, grpc_mdelem gmd DEBUG_ARGS) {
       break;
     case GRPC_MDELEM_STORAGE_INTERNED: {
       interned_metadata *md = (interned_metadata *)GRPC_MDELEM_DATA(gmd);
-#ifdef GRPC_METADATA_REFCOUNT_DEBUG
-      char *key_str = grpc_slice_to_c_string(md->key);
-      char *value_str = grpc_slice_to_c_string(md->value);
-      gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
-              "ELM UNREF:%p:%zu->%zu: '%s' = '%s'", (void *)md,
-              gpr_atm_no_barrier_load(&md->refcnt),
-              gpr_atm_no_barrier_load(&md->refcnt) - 1, key_str, value_str);
-      gpr_free(key_str);
-      gpr_free(value_str);
+#ifndef NDEBUG
+      if (GRPC_TRACER_ON(grpc_trace_metadata)) {
+        char *key_str = grpc_slice_to_c_string(md->key);
+        char *value_str = grpc_slice_to_c_string(md->value);
+        gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
+                "ELM UNREF:%p:%" PRIdPTR "->%" PRIdPTR ": '%s' = '%s'",
+                (void *)md, gpr_atm_no_barrier_load(&md->refcnt),
+                gpr_atm_no_barrier_load(&md->refcnt) - 1, key_str, value_str);
+        gpr_free(key_str);
+        gpr_free(value_str);
+      }
 #endif
       uint32_t hash = GRPC_MDSTR_KV_HASH(grpc_slice_hash(md->key),
                                          grpc_slice_hash(md->value));
@@ -443,15 +443,17 @@ void grpc_mdelem_unref(grpc_exec_ctx *exec_ctx, grpc_mdelem gmd DEBUG_ARGS) {
     }
     case GRPC_MDELEM_STORAGE_ALLOCATED: {
       allocated_metadata *md = (allocated_metadata *)GRPC_MDELEM_DATA(gmd);
-#ifdef GRPC_METADATA_REFCOUNT_DEBUG
-      char *key_str = grpc_slice_to_c_string(md->key);
-      char *value_str = grpc_slice_to_c_string(md->value);
-      gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
-              "ELM UNREF:%p:%zu->%zu: '%s' = '%s'", (void *)md,
-              gpr_atm_no_barrier_load(&md->refcnt),
-              gpr_atm_no_barrier_load(&md->refcnt) - 1, key_str, value_str);
-      gpr_free(key_str);
-      gpr_free(value_str);
+#ifndef NDEBUG
+      if (GRPC_TRACER_ON(grpc_trace_metadata)) {
+        char *key_str = grpc_slice_to_c_string(md->key);
+        char *value_str = grpc_slice_to_c_string(md->value);
+        gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
+                "ELM UNREF:%p:%" PRIdPTR "->%" PRIdPTR ": '%s' = '%s'",
+                (void *)md, gpr_atm_no_barrier_load(&md->refcnt),
+                gpr_atm_no_barrier_load(&md->refcnt) - 1, key_str, value_str);
+        gpr_free(key_str);
+        gpr_free(value_str);
+      }
 #endif
       const gpr_atm prev_refcount = gpr_atm_full_fetch_add(&md->refcnt, -1);
       GPR_ASSERT(prev_refcount >= 1);
diff --git a/src/core/lib/transport/metadata.h b/src/core/lib/transport/metadata.h
index f4ba86c854..974469e436 100644
--- a/src/core/lib/transport/metadata.h
+++ b/src/core/lib/transport/metadata.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -40,6 +25,10 @@
 
 #include "src/core/lib/iomgr/exec_ctx.h"
 
+#ifndef NDEBUG
+extern grpc_tracer_flag grpc_trace_metadata;
+#endif
+
 #ifdef __cplusplus
 extern "C" {
 #endif
@@ -147,9 +136,7 @@ void *grpc_mdelem_get_user_data(grpc_mdelem md,
 void *grpc_mdelem_set_user_data(grpc_mdelem md, void (*destroy_func)(void *),
                                 void *user_data);
 
-/* Reference counting */
-//#define GRPC_METADATA_REFCOUNT_DEBUG
-#ifdef GRPC_METADATA_REFCOUNT_DEBUG
+#ifndef NDEBUG
 #define GRPC_MDELEM_REF(s) grpc_mdelem_ref((s), __FILE__, __LINE__)
 #define GRPC_MDELEM_UNREF(exec_ctx, s) \
   grpc_mdelem_unref((exec_ctx), (s), __FILE__, __LINE__)
diff --git a/src/core/lib/transport/metadata_batch.c b/src/core/lib/transport/metadata_batch.c
index fa73244aa4..8f24b8527c 100644
--- a/src/core/lib/transport/metadata_batch.c
+++ b/src/core/lib/transport/metadata_batch.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/transport/metadata_batch.h b/src/core/lib/transport/metadata_batch.h
index 5471539e82..1b11a3e252 100644
--- a/src/core/lib/transport/metadata_batch.h
+++ b/src/core/lib/transport/metadata_batch.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/transport/pid_controller.c b/src/core/lib/transport/pid_controller.c
index c851564201..4b304f17b2 100644
--- a/src/core/lib/transport/pid_controller.c
+++ b/src/core/lib/transport/pid_controller.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/transport/pid_controller.h b/src/core/lib/transport/pid_controller.h
index 0a86521e90..9352b2643f 100644
--- a/src/core/lib/transport/pid_controller.h
+++ b/src/core/lib/transport/pid_controller.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/transport/service_config.c b/src/core/lib/transport/service_config.c
index 6aecb7fa93..0379d0010d 100644
--- a/src/core/lib/transport/service_config.c
+++ b/src/core/lib/transport/service_config.c
@@ -1,32 +1,17 @@
 //
-// Copyright 2015, Google Inc.
-// All rights reserved.
+// Copyright 2015 gRPC authors.
 //
-// Redistribution and use in source and binary forms, with or without
-// modification, are permitted provided that the following conditions are
-// met:
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
 //
-//     * Redistributions of source code must retain the above copyright
-// notice, this list of conditions and the following disclaimer.
-//     * Redistributions in binary form must reproduce the above
-// copyright notice, this list of conditions and the following disclaimer
-// in the documentation and/or other materials provided with the
-// distribution.
-//     * Neither the name of Google Inc. nor the names of its
-// contributors may be used to endorse or promote products derived from
-// this software without specific prior written permission.
+//     http://www.apache.org/licenses/LICENSE-2.0
 //
-// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
 //
 
 #include "src/core/lib/transport/service_config.h"
@@ -229,7 +214,7 @@ grpc_slice_hash_table* grpc_service_config_create_method_config_table(
   grpc_slice_hash_table* method_config_table = NULL;
   if (entries != NULL) {
     method_config_table =
-        grpc_slice_hash_table_create(num_entries, entries, destroy_value);
+        grpc_slice_hash_table_create(num_entries, entries, destroy_value, NULL);
     gpr_free(entries);
   }
   return method_config_table;
diff --git a/src/core/lib/transport/service_config.h b/src/core/lib/transport/service_config.h
index e0548b9c3f..84110abc36 100644
--- a/src/core/lib/transport/service_config.h
+++ b/src/core/lib/transport/service_config.h
@@ -1,32 +1,17 @@
 //
-// Copyright 2016, Google Inc.
-// All rights reserved.
+// Copyright 2016 gRPC authors.
 //
-// Redistribution and use in source and binary forms, with or without
-// modification, are permitted provided that the following conditions are
-// met:
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
 //
-//     * Redistributions of source code must retain the above copyright
-// notice, this list of conditions and the following disclaimer.
-//     * Redistributions in binary form must reproduce the above
-// copyright notice, this list of conditions and the following disclaimer
-// in the documentation and/or other materials provided with the
-// distribution.
-//     * Neither the name of Google Inc. nor the names of its
-// contributors may be used to endorse or promote products derived from
-// this software without specific prior written permission.
+//     http://www.apache.org/licenses/LICENSE-2.0
 //
-// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
 //
 
 #ifndef GRPC_CORE_LIB_TRANSPORT_SERVICE_CONFIG_H
diff --git a/src/core/lib/transport/static_metadata.c b/src/core/lib/transport/static_metadata.c
index 862cdaa8e0..2388f19f81 100644
--- a/src/core/lib/transport/static_metadata.c
+++ b/src/core/lib/transport/static_metadata.c
@@ -1,32 +1,17 @@
 /*
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  */
 
 /*
@@ -479,7 +464,8 @@ grpc_mdelem grpc_static_mdelem_for_static_strings(int a, int b) {
   if (a == -1 || b == -1) return GRPC_MDNULL;
   uint32_t k = (uint32_t)(a * 99 + b);
   uint32_t h = elems_phash(k);
-  return h < GPR_ARRAY_SIZE(elem_keys) && elem_keys[h] == k
+  return h < GPR_ARRAY_SIZE(elem_keys) && elem_keys[h] == k &&
+                 elem_idxs[h] != 255
              ? GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[elem_idxs[h]],
                                 GRPC_MDELEM_STORAGE_STATIC)
              : GRPC_MDNULL;
diff --git a/src/core/lib/transport/static_metadata.h b/src/core/lib/transport/static_metadata.h
index 84fb316fd6..baa86de142 100644
--- a/src/core/lib/transport/static_metadata.h
+++ b/src/core/lib/transport/static_metadata.h
@@ -1,32 +1,17 @@
 /*
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  */
 
 /*
diff --git a/src/core/lib/transport/status_conversion.c b/src/core/lib/transport/status_conversion.c
index af0ac89db7..9a76977e4b 100644
--- a/src/core/lib/transport/status_conversion.c
+++ b/src/core/lib/transport/status_conversion.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/transport/status_conversion.h b/src/core/lib/transport/status_conversion.h
index e6a23a606b..e93f3dfd9b 100644
--- a/src/core/lib/transport/status_conversion.h
+++ b/src/core/lib/transport/status_conversion.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/transport/timeout_encoding.c b/src/core/lib/transport/timeout_encoding.c
index 0d4d7e5a7e..02f179d6a3 100644
--- a/src/core/lib/transport/timeout_encoding.c
+++ b/src/core/lib/transport/timeout_encoding.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/transport/timeout_encoding.h b/src/core/lib/transport/timeout_encoding.h
index 4c8025d800..7ff35c4083 100644
--- a/src/core/lib/transport/timeout_encoding.h
+++ b/src/core/lib/transport/timeout_encoding.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/transport/transport.c b/src/core/lib/transport/transport.c
index 82c4e004b7..7281602d66 100644
--- a/src/core/lib/transport/transport.c
+++ b/src/core/lib/transport/transport.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -46,25 +31,34 @@
 #include "src/core/lib/support/string.h"
 #include "src/core/lib/transport/transport_impl.h"
 
-#ifdef GRPC_STREAM_REFCOUNT_DEBUG
+#ifndef NDEBUG
+grpc_tracer_flag grpc_trace_stream_refcount =
+    GRPC_TRACER_INITIALIZER(false, "stream_refcount");
+#endif
+
+#ifndef NDEBUG
 void grpc_stream_ref(grpc_stream_refcount *refcount, const char *reason) {
-  gpr_atm val = gpr_atm_no_barrier_load(&refcount->refs.count);
-  gpr_log(GPR_DEBUG, "%s %p:%p   REF %" PRIdPTR "->%" PRIdPTR " %s",
-          refcount->object_type, refcount, refcount->destroy.cb_arg, val,
-          val + 1, reason);
+  if (GRPC_TRACER_ON(grpc_trace_stream_refcount)) {
+    gpr_atm val = gpr_atm_no_barrier_load(&refcount->refs.count);
+    gpr_log(GPR_DEBUG, "%s %p:%p   REF %" PRIdPTR "->%" PRIdPTR " %s",
+            refcount->object_type, refcount, refcount->destroy.cb_arg, val,
+            val + 1, reason);
+  }
 #else
 void grpc_stream_ref(grpc_stream_refcount *refcount) {
 #endif
   gpr_ref_non_zero(&refcount->refs);
 }
 
-#ifdef GRPC_STREAM_REFCOUNT_DEBUG
+#ifndef NDEBUG
 void grpc_stream_unref(grpc_exec_ctx *exec_ctx, grpc_stream_refcount *refcount,
                        const char *reason) {
-  gpr_atm val = gpr_atm_no_barrier_load(&refcount->refs.count);
-  gpr_log(GPR_DEBUG, "%s %p:%p UNREF %" PRIdPTR "->%" PRIdPTR " %s",
-          refcount->object_type, refcount, refcount->destroy.cb_arg, val,
-          val - 1, reason);
+  if (GRPC_TRACER_ON(grpc_trace_stream_refcount)) {
+    gpr_atm val = gpr_atm_no_barrier_load(&refcount->refs.count);
+    gpr_log(GPR_DEBUG, "%s %p:%p UNREF %" PRIdPTR "->%" PRIdPTR " %s",
+            refcount->object_type, refcount, refcount->destroy.cb_arg, val,
+            val - 1, reason);
+  }
 #else
 void grpc_stream_unref(grpc_exec_ctx *exec_ctx,
                        grpc_stream_refcount *refcount) {
@@ -80,7 +74,7 @@ void grpc_stream_unref(grpc_exec_ctx *exec_ctx,
          there. */
       refcount->destroy.scheduler = grpc_executor_scheduler;
     }
-    grpc_closure_sched(exec_ctx, &refcount->destroy, GRPC_ERROR_NONE);
+    GRPC_CLOSURE_SCHED(exec_ctx, &refcount->destroy, GRPC_ERROR_NONE);
   }
 }
 
@@ -89,7 +83,7 @@ void grpc_stream_unref(grpc_exec_ctx *exec_ctx,
                             offsetof(grpc_stream_refcount, slice_refcount)))
 
 static void slice_stream_ref(void *p) {
-#ifdef GRPC_STREAM_REFCOUNT_DEBUG
+#ifndef NDEBUG
   grpc_stream_ref(STREAM_REF_FROM_SLICE_REF(p), "slice");
 #else
   grpc_stream_ref(STREAM_REF_FROM_SLICE_REF(p));
@@ -97,7 +91,7 @@ static void slice_stream_ref(void *p) {
 }
 
 static void slice_stream_unref(grpc_exec_ctx *exec_ctx, void *p) {
-#ifdef GRPC_STREAM_REFCOUNT_DEBUG
+#ifndef NDEBUG
   grpc_stream_unref(exec_ctx, STREAM_REF_FROM_SLICE_REF(p), "slice");
 #else
   grpc_stream_unref(exec_ctx, STREAM_REF_FROM_SLICE_REF(p));
@@ -117,7 +111,7 @@ static const grpc_slice_refcount_vtable stream_ref_slice_vtable = {
     .eq = grpc_slice_default_eq_impl,
     .hash = grpc_slice_default_hash_impl};
 
-#ifdef GRPC_STREAM_REFCOUNT_DEBUG
+#ifndef NDEBUG
 void grpc_stream_ref_init(grpc_stream_refcount *refcount, int initial_refs,
                           grpc_iomgr_cb_func cb, void *cb_arg,
                           const char *object_type) {
@@ -127,7 +121,7 @@ void grpc_stream_ref_init(grpc_stream_refcount *refcount, int initial_refs,
                           grpc_iomgr_cb_func cb, void *cb_arg) {
 #endif
   gpr_ref_init(&refcount->refs, initial_refs);
-  grpc_closure_init(&refcount->destroy, cb, cb_arg, grpc_schedule_on_exec_ctx);
+  GRPC_CLOSURE_INIT(&refcount->destroy, cb, cb_arg, grpc_schedule_on_exec_ctx);
   refcount->slice_refcount.vtable = &stream_ref_slice_vtable;
   refcount->slice_refcount.sub_refcount = &refcount->slice_refcount;
 }
@@ -213,20 +207,25 @@ grpc_endpoint *grpc_transport_get_endpoint(grpc_exec_ctx *exec_ctx,
   return transport->vtable->get_endpoint(exec_ctx, transport);
 }
 
+// grpc_transport_stream_op_batch_finish_with_failure
+// is a function that must always unref cancel_error
+// though it lives in lib, it handles transport stream ops sure
+// it's grpc_transport_stream_op_batch_finish_with_failure
+
 void grpc_transport_stream_op_batch_finish_with_failure(
     grpc_exec_ctx *exec_ctx, grpc_transport_stream_op_batch *op,
     grpc_error *error) {
   if (op->recv_message) {
-    grpc_closure_sched(exec_ctx, op->payload->recv_message.recv_message_ready,
+    GRPC_CLOSURE_SCHED(exec_ctx, op->payload->recv_message.recv_message_ready,
                        GRPC_ERROR_REF(error));
   }
   if (op->recv_initial_metadata) {
-    grpc_closure_sched(
+    GRPC_CLOSURE_SCHED(
         exec_ctx,
         op->payload->recv_initial_metadata.recv_initial_metadata_ready,
         GRPC_ERROR_REF(error));
   }
-  grpc_closure_sched(exec_ctx, op->on_complete, error);
+  GRPC_CLOSURE_SCHED(exec_ctx, op->on_complete, error);
   if (op->cancel_stream) {
     GRPC_ERROR_UNREF(op->payload->cancel_stream.cancel_error);
   }
@@ -241,13 +240,13 @@ typedef struct {
 static void destroy_made_transport_op(grpc_exec_ctx *exec_ctx, void *arg,
                                       grpc_error *error) {
   made_transport_op *op = arg;
-  grpc_closure_sched(exec_ctx, op->inner_on_complete, GRPC_ERROR_REF(error));
+  GRPC_CLOSURE_SCHED(exec_ctx, op->inner_on_complete, GRPC_ERROR_REF(error));
   gpr_free(op);
 }
 
 grpc_transport_op *grpc_make_transport_op(grpc_closure *on_complete) {
   made_transport_op *op = gpr_malloc(sizeof(*op));
-  grpc_closure_init(&op->outer_on_complete, destroy_made_transport_op, op,
+  GRPC_CLOSURE_INIT(&op->outer_on_complete, destroy_made_transport_op, op,
                     grpc_schedule_on_exec_ctx);
   op->inner_on_complete = on_complete;
   memset(&op->op, 0, sizeof(op->op));
@@ -267,14 +266,14 @@ static void destroy_made_transport_stream_op(grpc_exec_ctx *exec_ctx, void *arg,
   made_transport_stream_op *op = arg;
   grpc_closure *c = op->inner_on_complete;
   gpr_free(op);
-  grpc_closure_run(exec_ctx, c, GRPC_ERROR_REF(error));
+  GRPC_CLOSURE_RUN(exec_ctx, c, GRPC_ERROR_REF(error));
 }
 
 grpc_transport_stream_op_batch *grpc_make_transport_stream_op(
     grpc_closure *on_complete) {
   made_transport_stream_op *op = gpr_zalloc(sizeof(*op));
   op->op.payload = &op->payload;
-  grpc_closure_init(&op->outer_on_complete, destroy_made_transport_stream_op,
+  GRPC_CLOSURE_INIT(&op->outer_on_complete, destroy_made_transport_stream_op,
                     op, grpc_schedule_on_exec_ctx);
   op->inner_on_complete = on_complete;
   op->op.on_complete = &op->outer_on_complete;
diff --git a/src/core/lib/transport/transport.h b/src/core/lib/transport/transport.h
index 93369cc689..84e53e683a 100644
--- a/src/core/lib/transport/transport.h
+++ b/src/core/lib/transport/transport.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -57,18 +42,20 @@ typedef struct grpc_transport grpc_transport;
    for a stream. */
 typedef struct grpc_stream grpc_stream;
 
-//#define GRPC_STREAM_REFCOUNT_DEBUG
+#ifndef NDEBUG
+extern grpc_tracer_flag grpc_trace_stream_refcount;
+#endif
 
 typedef struct grpc_stream_refcount {
   gpr_refcount refs;
   grpc_closure destroy;
-#ifdef GRPC_STREAM_REFCOUNT_DEBUG
+#ifndef NDEBUG
   const char *object_type;
 #endif
   grpc_slice_refcount slice_refcount;
 } grpc_stream_refcount;
 
-#ifdef GRPC_STREAM_REFCOUNT_DEBUG
+#ifndef NDEBUG
 void grpc_stream_ref_init(grpc_stream_refcount *refcount, int initial_refs,
                           grpc_iomgr_cb_func cb, void *cb_arg,
                           const char *object_type);
@@ -127,10 +114,6 @@ typedef struct grpc_transport_stream_op_batch {
   /** Values for the stream op (fields set are determined by flags above) */
   grpc_transport_stream_op_batch_payload *payload;
 
-  /** Is the completion of this op covered by a poller (if false: the op should
-      complete independently of some pollset being polled) */
-  bool covered_by_poller : 1;
-
   /** Send initial metadata to the peer, from the provided metadata batch. */
   bool send_initial_metadata : 1;
 
@@ -184,6 +167,10 @@ struct grpc_transport_stream_op_batch_payload {
     uint32_t *recv_flags;
     /** Should be enqueued when initial metadata is ready to be processed. */
     grpc_closure *recv_initial_metadata_ready;
+    // If not NULL, will be set to true if trailing metadata is
+    // immediately available.  This may be a signal that we received a
+    // Trailers-Only response.
+    bool *trailing_metadata_available;
   } recv_initial_metadata;
 
   struct {
@@ -211,6 +198,8 @@ struct grpc_transport_stream_op_batch_payload {
         grpc_chttp2_grpc_status_to_http2_error. Send a RST_STREAM with this
         error. */
   struct {
+    // Error contract: the transport that gets this op must cause cancel_error
+    //                 to be unref'ed after processing it
     grpc_error *cancel_error;
   } cancel_stream;
 
@@ -225,9 +214,13 @@ typedef struct grpc_transport_op {
   /** connectivity monitoring - set connectivity_state to NULL to unsubscribe */
   grpc_closure *on_connectivity_state_change;
   grpc_connectivity_state *connectivity_state;
-  /** should the transport be disconnected */
+  /** should the transport be disconnected
+   * Error contract: the transport that gets this op must cause
+   *                 disconnect_with_error to be unref'ed after processing it */
   grpc_error *disconnect_with_error;
-  /** what should the goaway contain? */
+  /** what should the goaway contain?
+   * Error contract: the transport that gets this op must cause
+   *                 goaway_error to be unref'ed after processing it */
   grpc_error *goaway_error;
   /** set the callback for accepting new streams;
       this is a permanent callback, unlike the other one-shot closures.
diff --git a/src/core/lib/transport/transport_impl.h b/src/core/lib/transport/transport_impl.h
index bbb19a34bd..fc772c6dd1 100644
--- a/src/core/lib/transport/transport_impl.h
+++ b/src/core/lib/transport/transport_impl.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/lib/transport/transport_op_string.c b/src/core/lib/transport/transport_op_string.c
index 3a2a793e01..7b18229ba6 100644
--- a/src/core/lib/transport/transport_op_string.c
+++ b/src/core/lib/transport/transport_op_string.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -79,9 +64,6 @@ char *grpc_transport_stream_op_batch_string(
   gpr_strvec b;
   gpr_strvec_init(&b);
 
-  gpr_strvec_add(
-      &b, gpr_strdup(op->covered_by_poller ? "[COVERED]" : "[UNCOVERED]"));
-
   if (op->send_initial_metadata) {
     gpr_strvec_add(&b, gpr_strdup(" "));
     gpr_strvec_add(&b, gpr_strdup("SEND_INITIAL_METADATA{"));
diff --git a/src/core/plugin_registry/grpc_cronet_plugin_registry.c b/src/core/plugin_registry/grpc_cronet_plugin_registry.c
index 907e5a0f39..b468c03aa3 100644
--- a/src/core/plugin_registry/grpc_cronet_plugin_registry.c
+++ b/src/core/plugin_registry/grpc_cronet_plugin_registry.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/plugin_registry/grpc_plugin_registry.c b/src/core/plugin_registry/grpc_plugin_registry.c
index 25bda7a262..b0d06a3f43 100644
--- a/src/core/plugin_registry/grpc_plugin_registry.c
+++ b/src/core/plugin_registry/grpc_plugin_registry.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -41,6 +26,10 @@ extern void grpc_deadline_filter_init(void);
 extern void grpc_deadline_filter_shutdown(void);
 extern void grpc_client_channel_init(void);
 extern void grpc_client_channel_shutdown(void);
+extern void grpc_inproc_plugin_init(void);
+extern void grpc_inproc_plugin_shutdown(void);
+extern void grpc_resolver_fake_init(void);
+extern void grpc_resolver_fake_shutdown(void);
 extern void grpc_lb_policy_grpclb_init(void);
 extern void grpc_lb_policy_grpclb_shutdown(void);
 extern void grpc_lb_policy_pick_first_init(void);
@@ -61,6 +50,8 @@ extern void grpc_max_age_filter_init(void);
 extern void grpc_max_age_filter_shutdown(void);
 extern void grpc_message_size_filter_init(void);
 extern void grpc_message_size_filter_shutdown(void);
+extern void grpc_workaround_cronet_compression_filter_init(void);
+extern void grpc_workaround_cronet_compression_filter_shutdown(void);
 
 void grpc_register_built_in_plugins(void) {
   grpc_register_plugin(grpc_http_filters_init,
@@ -71,6 +62,10 @@ void grpc_register_built_in_plugins(void) {
                        grpc_deadline_filter_shutdown);
   grpc_register_plugin(grpc_client_channel_init,
                        grpc_client_channel_shutdown);
+  grpc_register_plugin(grpc_inproc_plugin_init,
+                       grpc_inproc_plugin_shutdown);
+  grpc_register_plugin(grpc_resolver_fake_init,
+                       grpc_resolver_fake_shutdown);
   grpc_register_plugin(grpc_lb_policy_grpclb_init,
                        grpc_lb_policy_grpclb_shutdown);
   grpc_register_plugin(grpc_lb_policy_pick_first_init,
@@ -91,4 +86,6 @@ void grpc_register_built_in_plugins(void) {
                        grpc_max_age_filter_shutdown);
   grpc_register_plugin(grpc_message_size_filter_init,
                        grpc_message_size_filter_shutdown);
+  grpc_register_plugin(grpc_workaround_cronet_compression_filter_init,
+                       grpc_workaround_cronet_compression_filter_shutdown);
 }
diff --git a/src/core/plugin_registry/grpc_unsecure_plugin_registry.c b/src/core/plugin_registry/grpc_unsecure_plugin_registry.c
index 05d4771bce..7eb599d81a 100644
--- a/src/core/plugin_registry/grpc_unsecure_plugin_registry.c
+++ b/src/core/plugin_registry/grpc_unsecure_plugin_registry.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2016, Google Inc.
- * All rights reserved.
+ * Copyright 2016 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -41,12 +26,16 @@ extern void grpc_deadline_filter_init(void);
 extern void grpc_deadline_filter_shutdown(void);
 extern void grpc_client_channel_init(void);
 extern void grpc_client_channel_shutdown(void);
+extern void grpc_inproc_plugin_init(void);
+extern void grpc_inproc_plugin_shutdown(void);
 extern void grpc_resolver_dns_ares_init(void);
 extern void grpc_resolver_dns_ares_shutdown(void);
 extern void grpc_resolver_dns_native_init(void);
 extern void grpc_resolver_dns_native_shutdown(void);
 extern void grpc_resolver_sockaddr_init(void);
 extern void grpc_resolver_sockaddr_shutdown(void);
+extern void grpc_resolver_fake_init(void);
+extern void grpc_resolver_fake_shutdown(void);
 extern void grpc_load_reporting_plugin_init(void);
 extern void grpc_load_reporting_plugin_shutdown(void);
 extern void grpc_lb_policy_grpclb_init(void);
@@ -61,6 +50,8 @@ extern void grpc_max_age_filter_init(void);
 extern void grpc_max_age_filter_shutdown(void);
 extern void grpc_message_size_filter_init(void);
 extern void grpc_message_size_filter_shutdown(void);
+extern void grpc_workaround_cronet_compression_filter_init(void);
+extern void grpc_workaround_cronet_compression_filter_shutdown(void);
 
 void grpc_register_built_in_plugins(void) {
   grpc_register_plugin(grpc_http_filters_init,
@@ -71,12 +62,16 @@ void grpc_register_built_in_plugins(void) {
                        grpc_deadline_filter_shutdown);
   grpc_register_plugin(grpc_client_channel_init,
                        grpc_client_channel_shutdown);
+  grpc_register_plugin(grpc_inproc_plugin_init,
+                       grpc_inproc_plugin_shutdown);
   grpc_register_plugin(grpc_resolver_dns_ares_init,
                        grpc_resolver_dns_ares_shutdown);
   grpc_register_plugin(grpc_resolver_dns_native_init,
                        grpc_resolver_dns_native_shutdown);
   grpc_register_plugin(grpc_resolver_sockaddr_init,
                        grpc_resolver_sockaddr_shutdown);
+  grpc_register_plugin(grpc_resolver_fake_init,
+                       grpc_resolver_fake_shutdown);
   grpc_register_plugin(grpc_load_reporting_plugin_init,
                        grpc_load_reporting_plugin_shutdown);
   grpc_register_plugin(grpc_lb_policy_grpclb_init,
@@ -91,4 +86,6 @@ void grpc_register_built_in_plugins(void) {
                        grpc_max_age_filter_shutdown);
   grpc_register_plugin(grpc_message_size_filter_init,
                        grpc_message_size_filter_shutdown);
+  grpc_register_plugin(grpc_workaround_cronet_compression_filter_init,
+                       grpc_workaround_cronet_compression_filter_shutdown);
 }
diff --git a/src/core/tsi/fake_transport_security.c b/src/core/tsi/fake_transport_security.c
index 4925d19f96..1280680663 100644
--- a/src/core/tsi/fake_transport_security.c
+++ b/src/core/tsi/fake_transport_security.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -46,6 +31,7 @@
 #define TSI_FAKE_FRAME_HEADER_SIZE 4
 #define TSI_FAKE_FRAME_INITIAL_ALLOCATED_SIZE 64
 #define TSI_FAKE_DEFAULT_FRAME_SIZE 16384
+#define TSI_FAKE_HANDSHAKER_OUTGOING_BUFFER_INITIAL_SIZE 256
 
 /* --- Structure definitions. ---*/
 
@@ -74,8 +60,10 @@ typedef struct {
   int is_client;
   tsi_fake_handshake_message next_message_to_send;
   int needs_incoming_message;
-  tsi_fake_frame incoming;
-  tsi_fake_frame outgoing;
+  tsi_fake_frame incoming_frame;
+  tsi_fake_frame outgoing_frame;
+  unsigned char *outgoing_bytes_buffer;
+  size_t outgoing_bytes_buffer_size;
   tsi_result result;
 } tsi_fake_handshaker;
 
@@ -131,27 +119,23 @@ static void tsi_fake_frame_reset(tsi_fake_frame *frame, int needs_draining) {
   if (!needs_draining) frame->size = 0;
 }
 
-/* Returns 1 if successful, 0 otherwise. */
-static int tsi_fake_frame_ensure_size(tsi_fake_frame *frame) {
+/* Checks if the frame's allocated size is at least frame->size, and reallocs
+ * more memory if necessary. */
+static void tsi_fake_frame_ensure_size(tsi_fake_frame *frame) {
   if (frame->data == NULL) {
     frame->allocated_size = frame->size;
     frame->data = gpr_malloc(frame->allocated_size);
-    if (frame->data == NULL) return 0;
   } else if (frame->size > frame->allocated_size) {
     unsigned char *new_data = gpr_realloc(frame->data, frame->size);
-    if (new_data == NULL) {
-      gpr_free(frame->data);
-      frame->data = NULL;
-      return 0;
-    }
     frame->data = new_data;
     frame->allocated_size = frame->size;
   }
-  return 1;
 }
 
-/* This method should not be called if frame->needs_framing is not 0.  */
-static tsi_result fill_frame_from_bytes(const unsigned char *incoming_bytes,
+/* Decodes the serialized fake frame contained in incoming_bytes, and fills
+ * frame with the contents of the decoded frame.
+ * This method should not be called if frame->needs_framing is not 0.  */
+static tsi_result tsi_fake_frame_decode(const unsigned char *incoming_bytes,
                                         size_t *incoming_bytes_size,
                                         tsi_fake_frame *frame) {
   size_t available_size = *incoming_bytes_size;
@@ -162,7 +146,6 @@ static tsi_result fill_frame_from_bytes(const unsigned char *incoming_bytes,
   if (frame->data == NULL) {
     frame->allocated_size = TSI_FAKE_FRAME_INITIAL_ALLOCATED_SIZE;
     frame->data = gpr_malloc(frame->allocated_size);
-    if (frame->data == NULL) return TSI_OUT_OF_RESOURCES;
   }
 
   if (frame->offset < TSI_FAKE_FRAME_HEADER_SIZE) {
@@ -180,7 +163,7 @@ static tsi_result fill_frame_from_bytes(const unsigned char *incoming_bytes,
     frame->offset += to_read_size;
     available_size -= to_read_size;
     frame->size = load32_little_endian(frame->data);
-    if (!tsi_fake_frame_ensure_size(frame)) return TSI_OUT_OF_RESOURCES;
+    tsi_fake_frame_ensure_size(frame);
   }
 
   to_read_size = frame->size - frame->offset;
@@ -198,10 +181,12 @@ static tsi_result fill_frame_from_bytes(const unsigned char *incoming_bytes,
   return TSI_OK;
 }
 
-/* This method should not be called if frame->needs_framing is 0.  */
-static tsi_result drain_frame_to_bytes(unsigned char *outgoing_bytes,
-                                       size_t *outgoing_bytes_size,
-                                       tsi_fake_frame *frame) {
+/* Encodes a fake frame into its wire format and places the result in
+ * outgoing_bytes. outgoing_bytes_size indicates the size of the encoded frame.
+ * This method should not be called if frame->needs_framing is 0.  */
+static tsi_result tsi_fake_frame_encode(unsigned char *outgoing_bytes,
+                                        size_t *outgoing_bytes_size,
+                                        tsi_fake_frame *frame) {
   size_t to_write_size = frame->size - frame->offset;
   if (!frame->needs_draining) return TSI_INTERNAL_ERROR;
   if (*outgoing_bytes_size < to_write_size) {
@@ -215,17 +200,20 @@ static tsi_result drain_frame_to_bytes(unsigned char *outgoing_bytes,
   return TSI_OK;
 }
 
-static tsi_result bytes_to_frame(unsigned char *bytes, size_t bytes_size,
-                                 tsi_fake_frame *frame) {
+/* Sets the payload of a fake frame to contain the given data blob, where
+ * data_size indicates the size of data. */
+static tsi_result tsi_fake_frame_set_data(unsigned char *data, size_t data_size,
+                                          tsi_fake_frame *frame) {
   frame->offset = 0;
-  frame->size = bytes_size + TSI_FAKE_FRAME_HEADER_SIZE;
-  if (!tsi_fake_frame_ensure_size(frame)) return TSI_OUT_OF_RESOURCES;
+  frame->size = data_size + TSI_FAKE_FRAME_HEADER_SIZE;
+  tsi_fake_frame_ensure_size(frame);
   store32_little_endian((uint32_t)frame->size, frame->data);
-  memcpy(frame->data + TSI_FAKE_FRAME_HEADER_SIZE, bytes, bytes_size);
+  memcpy(frame->data + TSI_FAKE_FRAME_HEADER_SIZE, data, data_size);
   tsi_fake_frame_reset(frame, 1 /* needs draining */);
   return TSI_OK;
 }
 
+/* Destroys the contents of a fake frame. */
 static void tsi_fake_frame_destruct(tsi_fake_frame *frame) {
   if (frame->data != NULL) gpr_free(frame->data);
 }
@@ -250,7 +238,7 @@ static tsi_result fake_protector_protect(tsi_frame_protector *self,
   if (frame->needs_draining) {
     drained_size = saved_output_size - *num_bytes_written;
     result =
-        drain_frame_to_bytes(protected_output_frames, &drained_size, frame);
+        tsi_fake_frame_encode(protected_output_frames, &drained_size, frame);
     *num_bytes_written += drained_size;
     protected_output_frames += drained_size;
     if (result != TSI_OK) {
@@ -269,15 +257,15 @@ static tsi_result fake_protector_protect(tsi_frame_protector *self,
     size_t written_in_frame_size = 0;
     store32_little_endian((uint32_t)impl->max_frame_size, frame_header);
     written_in_frame_size = TSI_FAKE_FRAME_HEADER_SIZE;
-    result = fill_frame_from_bytes(frame_header, &written_in_frame_size, frame);
+    result = tsi_fake_frame_decode(frame_header, &written_in_frame_size, frame);
     if (result != TSI_INCOMPLETE_DATA) {
-      gpr_log(GPR_ERROR, "fill_frame_from_bytes returned %s",
+      gpr_log(GPR_ERROR, "tsi_fake_frame_decode returned %s",
               tsi_result_to_string(result));
       return result;
     }
   }
   result =
-      fill_frame_from_bytes(unprotected_bytes, unprotected_bytes_size, frame);
+      tsi_fake_frame_decode(unprotected_bytes, unprotected_bytes_size, frame);
   if (result != TSI_OK) {
     if (result == TSI_INCOMPLETE_DATA) result = TSI_OK;
     return result;
@@ -287,7 +275,7 @@ static tsi_result fake_protector_protect(tsi_frame_protector *self,
   if (!frame->needs_draining) return TSI_INTERNAL_ERROR;
   if (frame->offset != 0) return TSI_INTERNAL_ERROR;
   drained_size = saved_output_size - *num_bytes_written;
-  result = drain_frame_to_bytes(protected_output_frames, &drained_size, frame);
+  result = tsi_fake_frame_encode(protected_output_frames, &drained_size, frame);
   *num_bytes_written += drained_size;
   if (result == TSI_INCOMPLETE_DATA) result = TSI_OK;
   return result;
@@ -307,8 +295,8 @@ static tsi_result fake_protector_protect_flush(
     store32_little_endian((uint32_t)frame->size,
                           frame->data); /* Overwrite header. */
   }
-  result = drain_frame_to_bytes(protected_output_frames,
-                                protected_output_frames_size, frame);
+  result = tsi_fake_frame_encode(protected_output_frames,
+                                 protected_output_frames_size, frame);
   if (result == TSI_INCOMPLETE_DATA) result = TSI_OK;
   *still_pending_size = frame->size - frame->offset;
   return result;
@@ -331,7 +319,7 @@ static tsi_result fake_protector_unprotect(
     /* Go past the header if needed. */
     if (frame->offset == 0) frame->offset = TSI_FAKE_FRAME_HEADER_SIZE;
     drained_size = saved_output_size - *num_bytes_written;
-    result = drain_frame_to_bytes(unprotected_bytes, &drained_size, frame);
+    result = tsi_fake_frame_encode(unprotected_bytes, &drained_size, frame);
     unprotected_bytes += drained_size;
     *num_bytes_written += drained_size;
     if (result != TSI_OK) {
@@ -345,7 +333,7 @@ static tsi_result fake_protector_unprotect(
 
   /* Now process the protected_bytes. */
   if (frame->needs_draining) return TSI_INTERNAL_ERROR;
-  result = fill_frame_from_bytes(protected_frames_bytes,
+  result = tsi_fake_frame_decode(protected_frames_bytes,
                                  protected_frames_bytes_size, frame);
   if (result != TSI_OK) {
     if (result == TSI_INCOMPLETE_DATA) result = TSI_OK;
@@ -357,7 +345,7 @@ static tsi_result fake_protector_unprotect(
   if (frame->offset != 0) return TSI_INTERNAL_ERROR;
   frame->offset = TSI_FAKE_FRAME_HEADER_SIZE; /* Go past the header. */
   drained_size = saved_output_size - *num_bytes_written;
-  result = drain_frame_to_bytes(unprotected_bytes, &drained_size, frame);
+  result = tsi_fake_frame_encode(unprotected_bytes, &drained_size, frame);
   *num_bytes_written += drained_size;
   if (result == TSI_INCOMPLETE_DATA) result = TSI_OK;
   return result;
@@ -375,6 +363,72 @@ static const tsi_frame_protector_vtable frame_protector_vtable = {
     fake_protector_unprotect, fake_protector_destroy,
 };
 
+/* --- tsi_handshaker_result methods implementation. ---*/
+
+typedef struct {
+  tsi_handshaker_result base;
+  unsigned char *unused_bytes;
+  size_t unused_bytes_size;
+} fake_handshaker_result;
+
+static tsi_result fake_handshaker_result_extract_peer(
+    const tsi_handshaker_result *self, tsi_peer *peer) {
+  /* Construct a tsi_peer with 1 property: certificate type. */
+  tsi_result result = tsi_construct_peer(1, peer);
+  if (result != TSI_OK) return result;
+  result = tsi_construct_string_peer_property_from_cstring(
+      TSI_CERTIFICATE_TYPE_PEER_PROPERTY, TSI_FAKE_CERTIFICATE_TYPE,
+      &peer->properties[0]);
+  if (result != TSI_OK) tsi_peer_destruct(peer);
+  return result;
+}
+
+static tsi_result fake_handshaker_result_create_frame_protector(
+    const tsi_handshaker_result *self, size_t *max_output_protected_frame_size,
+    tsi_frame_protector **protector) {
+  *protector = tsi_create_fake_frame_protector(max_output_protected_frame_size);
+  return TSI_OK;
+}
+
+static tsi_result fake_handshaker_result_get_unused_bytes(
+    const tsi_handshaker_result *self, unsigned char **bytes,
+    size_t *bytes_size) {
+  fake_handshaker_result *result = (fake_handshaker_result *)self;
+  *bytes_size = result->unused_bytes_size;
+  *bytes = result->unused_bytes;
+  return TSI_OK;
+}
+
+static void fake_handshaker_result_destroy(tsi_handshaker_result *self) {
+  fake_handshaker_result *result = (fake_handshaker_result *)self;
+  gpr_free(result->unused_bytes);
+  gpr_free(self);
+}
+
+static const tsi_handshaker_result_vtable handshaker_result_vtable = {
+    fake_handshaker_result_extract_peer,
+    fake_handshaker_result_create_frame_protector,
+    fake_handshaker_result_get_unused_bytes, fake_handshaker_result_destroy,
+};
+
+static tsi_result fake_handshaker_result_create(
+    const unsigned char *unused_bytes, size_t unused_bytes_size,
+    tsi_handshaker_result **handshaker_result) {
+  if ((unused_bytes_size > 0 && unused_bytes == NULL) ||
+      handshaker_result == NULL) {
+    return TSI_INVALID_ARGUMENT;
+  }
+  fake_handshaker_result *result = gpr_zalloc(sizeof(*result));
+  result->base.vtable = &handshaker_result_vtable;
+  if (unused_bytes_size > 0) {
+    result->unused_bytes = gpr_malloc(unused_bytes_size);
+    memcpy(result->unused_bytes, unused_bytes, unused_bytes_size);
+  }
+  result->unused_bytes_size = unused_bytes_size;
+  *handshaker_result = &result->base;
+  return TSI_OK;
+}
+
 /* --- tsi_handshaker methods implementation. ---*/
 
 static tsi_result fake_handshaker_get_bytes_to_send_to_peer(
@@ -385,13 +439,13 @@ static tsi_result fake_handshaker_get_bytes_to_send_to_peer(
     *bytes_size = 0;
     return TSI_OK;
   }
-  if (!impl->outgoing.needs_draining) {
+  if (!impl->outgoing_frame.needs_draining) {
     tsi_fake_handshake_message next_message_to_send =
         impl->next_message_to_send + 2;
     const char *msg_string =
         tsi_fake_handshake_message_to_string(impl->next_message_to_send);
-    result = bytes_to_frame((unsigned char *)msg_string, strlen(msg_string),
-                            &impl->outgoing);
+    result = tsi_fake_frame_set_data((unsigned char *)msg_string,
+                                     strlen(msg_string), &impl->outgoing_frame);
     if (result != TSI_OK) return result;
     if (next_message_to_send > TSI_FAKE_HANDSHAKE_MESSAGE_MAX) {
       next_message_to_send = TSI_FAKE_HANDSHAKE_MESSAGE_MAX;
@@ -403,7 +457,7 @@ static tsi_result fake_handshaker_get_bytes_to_send_to_peer(
     }
     impl->next_message_to_send = next_message_to_send;
   }
-  result = drain_frame_to_bytes(bytes, bytes_size, &impl->outgoing);
+  result = tsi_fake_frame_encode(bytes, bytes_size, &impl->outgoing_frame);
   if (result != TSI_OK) return result;
   if (!impl->is_client &&
       impl->next_message_to_send == TSI_FAKE_HANDSHAKE_MESSAGE_MAX) {
@@ -429,12 +483,12 @@ static tsi_result fake_handshaker_process_bytes_from_peer(
     *bytes_size = 0;
     return TSI_OK;
   }
-  result = fill_frame_from_bytes(bytes, bytes_size, &impl->incoming);
+  result = tsi_fake_frame_decode(bytes, bytes_size, &impl->incoming_frame);
   if (result != TSI_OK) return result;
 
   /* We now have a complete frame. */
   result = tsi_fake_handshake_message_from_string(
-      (const char *)impl->incoming.data + TSI_FAKE_FRAME_HEADER_SIZE,
+      (const char *)impl->incoming_frame.data + TSI_FAKE_FRAME_HEADER_SIZE,
       &received_msg);
   if (result != TSI_OK) {
     impl->result = result;
@@ -449,7 +503,7 @@ static tsi_result fake_handshaker_process_bytes_from_peer(
     gpr_log(GPR_INFO, "%s received %s.", impl->is_client ? "Client" : "Server",
             tsi_fake_handshake_message_to_string(received_msg));
   }
-  tsi_fake_frame_reset(&impl->incoming, 0 /* needs_draining */);
+  tsi_fake_frame_reset(&impl->incoming_frame, 0 /* needs_draining */);
   impl->needs_incoming_message = 0;
   if (impl->next_message_to_send == TSI_FAKE_HANDSHAKE_MESSAGE_MAX) {
     /* We're done. */
@@ -466,40 +520,86 @@ static tsi_result fake_handshaker_get_result(tsi_handshaker *self) {
   return impl->result;
 }
 
-static tsi_result fake_handshaker_extract_peer(tsi_handshaker *self,
-                                               tsi_peer *peer) {
-  tsi_result result = tsi_construct_peer(1, peer);
-  if (result != TSI_OK) return result;
-  result = tsi_construct_string_peer_property_from_cstring(
-      TSI_CERTIFICATE_TYPE_PEER_PROPERTY, TSI_FAKE_CERTIFICATE_TYPE,
-      &peer->properties[0]);
-  if (result != TSI_OK) tsi_peer_destruct(peer);
-  return result;
-}
-
-static tsi_result fake_handshaker_create_frame_protector(
-    tsi_handshaker *self, size_t *max_protected_frame_size,
-    tsi_frame_protector **protector) {
-  *protector = tsi_create_fake_protector(max_protected_frame_size);
-  if (*protector == NULL) return TSI_OUT_OF_RESOURCES;
-  return TSI_OK;
-}
-
 static void fake_handshaker_destroy(tsi_handshaker *self) {
   tsi_fake_handshaker *impl = (tsi_fake_handshaker *)self;
-  tsi_fake_frame_destruct(&impl->incoming);
-  tsi_fake_frame_destruct(&impl->outgoing);
+  tsi_fake_frame_destruct(&impl->incoming_frame);
+  tsi_fake_frame_destruct(&impl->outgoing_frame);
+  gpr_free(impl->outgoing_bytes_buffer);
   gpr_free(self);
 }
 
+static tsi_result fake_handshaker_next(
+    tsi_handshaker *self, const unsigned char *received_bytes,
+    size_t received_bytes_size, unsigned char **bytes_to_send,
+    size_t *bytes_to_send_size, tsi_handshaker_result **handshaker_result,
+    tsi_handshaker_on_next_done_cb cb, void *user_data) {
+  /* Sanity check the arguments. */
+  if ((received_bytes_size > 0 && received_bytes == NULL) ||
+      bytes_to_send == NULL || bytes_to_send_size == NULL ||
+      handshaker_result == NULL) {
+    return TSI_INVALID_ARGUMENT;
+  }
+  tsi_fake_handshaker *handshaker = (tsi_fake_handshaker *)self;
+  tsi_result result = TSI_OK;
+
+  /* Decode and process a handshake frame from the peer. */
+  size_t consumed_bytes_size = received_bytes_size;
+  if (received_bytes_size > 0) {
+    result = fake_handshaker_process_bytes_from_peer(self, received_bytes,
+                                                     &consumed_bytes_size);
+    if (result != TSI_OK) return result;
+  }
+
+  /* Create a handshake message to send to the peer and encode it as a fake
+   * frame. */
+  size_t offset = 0;
+  do {
+    size_t sent_bytes_size = handshaker->outgoing_bytes_buffer_size - offset;
+    result = fake_handshaker_get_bytes_to_send_to_peer(
+        self, handshaker->outgoing_bytes_buffer + offset, &sent_bytes_size);
+    offset += sent_bytes_size;
+    if (result == TSI_INCOMPLETE_DATA) {
+      handshaker->outgoing_bytes_buffer_size *= 2;
+      handshaker->outgoing_bytes_buffer =
+          gpr_realloc(handshaker->outgoing_bytes_buffer,
+                      handshaker->outgoing_bytes_buffer_size);
+    }
+  } while (result == TSI_INCOMPLETE_DATA);
+  if (result != TSI_OK) return result;
+  *bytes_to_send = handshaker->outgoing_bytes_buffer;
+  *bytes_to_send_size = offset;
+
+  /* Check if the handshake was completed. */
+  if (fake_handshaker_get_result(self) == TSI_HANDSHAKE_IN_PROGRESS) {
+    *handshaker_result = NULL;
+  } else {
+    /* Calculate the unused bytes. */
+    const unsigned char *unused_bytes = NULL;
+    size_t unused_bytes_size = received_bytes_size - consumed_bytes_size;
+    if (unused_bytes_size > 0) {
+      unused_bytes = received_bytes + consumed_bytes_size;
+    }
+
+    /* Create a handshaker_result containing the unused bytes. */
+    result = fake_handshaker_result_create(unused_bytes, unused_bytes_size,
+                                           handshaker_result);
+    if (result == TSI_OK) {
+      /* Indicate that the handshake has completed and that a handshaker_result
+       * has been created. */
+      self->handshaker_result_created = true;
+    }
+  }
+  return result;
+}
+
 static const tsi_handshaker_vtable handshaker_vtable = {
-    fake_handshaker_get_bytes_to_send_to_peer,
-    fake_handshaker_process_bytes_from_peer,
-    fake_handshaker_get_result,
-    fake_handshaker_extract_peer,
-    fake_handshaker_create_frame_protector,
+    NULL, /* get_bytes_to_send_to_peer -- deprecated */
+    NULL, /* process_bytes_from_peer   -- deprecated */
+    NULL, /* get_result                -- deprecated */
+    NULL, /* extract_peer              -- deprecated */
+    NULL, /* create_frame_protector    -- deprecated */
     fake_handshaker_destroy,
-    NULL,
+    fake_handshaker_next,
 };
 
 tsi_handshaker *tsi_create_fake_handshaker(int is_client) {
@@ -507,6 +607,9 @@ tsi_handshaker *tsi_create_fake_handshaker(int is_client) {
   impl->base.vtable = &handshaker_vtable;
   impl->is_client = is_client;
   impl->result = TSI_HANDSHAKE_IN_PROGRESS;
+  impl->outgoing_bytes_buffer_size =
+      TSI_FAKE_HANDSHAKER_OUTGOING_BUFFER_INITIAL_SIZE;
+  impl->outgoing_bytes_buffer = gpr_malloc(impl->outgoing_bytes_buffer_size);
   if (is_client) {
     impl->needs_incoming_message = 0;
     impl->next_message_to_send = TSI_FAKE_CLIENT_INIT;
@@ -517,7 +620,7 @@ tsi_handshaker *tsi_create_fake_handshaker(int is_client) {
   return &impl->base;
 }
 
-tsi_frame_protector *tsi_create_fake_protector(
+tsi_frame_protector *tsi_create_fake_frame_protector(
     size_t *max_protected_frame_size) {
   tsi_fake_frame_protector *impl = gpr_zalloc(sizeof(*impl));
   impl->max_frame_size = (max_protected_frame_size == NULL)
diff --git a/src/core/tsi/fake_transport_security.h b/src/core/tsi/fake_transport_security.h
index 0697c7279f..934b3cbeb2 100644
--- a/src/core/tsi/fake_transport_security.h
+++ b/src/core/tsi/fake_transport_security.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -51,7 +36,7 @@ extern "C" {
 tsi_handshaker *tsi_create_fake_handshaker(int is_client);
 
 /* Creates a protector directly without going through the handshake phase. */
-tsi_frame_protector *tsi_create_fake_protector(
+tsi_frame_protector *tsi_create_fake_frame_protector(
     size_t *max_protected_frame_size);
 
 #ifdef __cplusplus
diff --git a/src/core/tsi/ssl_transport_security.c b/src/core/tsi/ssl_transport_security.c
index 59fd2b1c93..1fd65928f9 100644
--- a/src/core/tsi/ssl_transport_security.c
+++ b/src/core/tsi/ssl_transport_security.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -426,15 +411,11 @@ static tsi_result do_ssl_read(SSL *ssl, unsigned char *unprotected_bytes,
   GPR_ASSERT(*unprotected_bytes_size <= INT_MAX);
   read_from_ssl =
       SSL_read(ssl, unprotected_bytes, (int)*unprotected_bytes_size);
-  if (read_from_ssl == 0) {
-    gpr_log(GPR_ERROR, "SSL_read returned 0 unexpectedly.");
-    return TSI_INTERNAL_ERROR;
-  }
-  if (read_from_ssl < 0) {
+  if (read_from_ssl <= 0) {
     read_from_ssl = SSL_get_error(ssl, read_from_ssl);
     switch (read_from_ssl) {
-      case SSL_ERROR_WANT_READ:
-        /* We need more data to finish the frame. */
+      case SSL_ERROR_ZERO_RETURN: /* Received a close_notify alert. */
+      case SSL_ERROR_WANT_READ:   /* We need more data to finish the frame. */
         *unprotected_bytes_size = 0;
         return TSI_OK;
       case SSL_ERROR_WANT_WRITE:
diff --git a/src/core/tsi/ssl_transport_security.h b/src/core/tsi/ssl_transport_security.h
index 3117571d9f..177599930b 100644
--- a/src/core/tsi/ssl_transport_security.h
+++ b/src/core/tsi/ssl_transport_security.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/tsi/ssl_types.h b/src/core/tsi/ssl_types.h
index 065cb86800..3788643355 100644
--- a/src/core/tsi/ssl_types.h
+++ b/src/core/tsi/ssl_types.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/tsi/test_creds/BUILD b/src/core/tsi/test_creds/BUILD
index 5cf04caf17..4b0786d7b8 100644
--- a/src/core/tsi/test_creds/BUILD
+++ b/src/core/tsi/test_creds/BUILD
@@ -1,33 +1,18 @@
-# Copyright 2017, Google Inc.
-# All rights reserved.
+# Copyright 2017 gRPC authors.
 #
-# Redistribution and use in source and binary forms, with or without
-# modification, are permitted provided that the following conditions are
-# met:
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
 #
-#     * Redistributions of source code must retain the above copyright
-# notice, this list of conditions and the following disclaimer.
-#     * Redistributions in binary form must reproduce the above
-# copyright notice, this list of conditions and the following disclaimer
-# in the documentation and/or other materials provided with the
-# distribution.
-#     * Neither the name of Google Inc. nor the names of its
-# contributors may be used to endorse or promote products derived from
-# this software without specific prior written permission.
+#     http://www.apache.org/licenses/LICENSE-2.0
 #
-# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
 
-licenses(["notice"])  # 3-clause BSD
+licenses(["notice"])  # Apache v2
 
 exports_files([
     "ca.pem",
diff --git a/src/core/tsi/transport_security.c b/src/core/tsi/transport_security.c
index 4efcf8f43d..be11d64472 100644
--- a/src/core/tsi/transport_security.c
+++ b/src/core/tsi/transport_security.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
@@ -41,7 +26,7 @@
 
 /* --- Tracing. --- */
 
-grpc_tracer_flag tsi_tracing_enabled = GRPC_TRACER_INITIALIZER(false);
+grpc_tracer_flag tsi_tracing_enabled = GRPC_TRACER_INITIALIZER(false, "tsi");
 
 /* --- tsi_result common implementation. --- */
 
diff --git a/src/core/tsi/transport_security.h b/src/core/tsi/transport_security.h
index 2422f92076..4a56c25602 100644
--- a/src/core/tsi/transport_security.h
+++ b/src/core/tsi/transport_security.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/tsi/transport_security_adapter.c b/src/core/tsi/transport_security_adapter.c
index 9f2147b530..a0564945e4 100644
--- a/src/core/tsi/transport_security_adapter.c
+++ b/src/core/tsi/transport_security_adapter.c
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2017, Google Inc.
- * All rights reserved.
+ * Copyright 2017 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/tsi/transport_security_adapter.h b/src/core/tsi/transport_security_adapter.h
index 400df2f11b..02f33d4c1c 100644
--- a/src/core/tsi/transport_security_adapter.h
+++ b/src/core/tsi/transport_security_adapter.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2017, Google Inc.
- * All rights reserved.
+ * Copyright 2017 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */
 
diff --git a/src/core/tsi/transport_security_interface.h b/src/core/tsi/transport_security_interface.h
index 8a3fff6a17..137f8ee5c3 100644
--- a/src/core/tsi/transport_security_interface.h
+++ b/src/core/tsi/transport_security_interface.h
@@ -1,33 +1,18 @@
 /*
  *
- * Copyright 2015, Google Inc.
- * All rights reserved.
+ * Copyright 2015 gRPC authors.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
+ *     http://www.apache.org/licenses/LICENSE-2.0
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  */