Merge remote-tracking branch 'upstream/master' into client_channel_cleanup

45 files changed, 1141 insertions, 122 deletions

diff --git a/BUILD b/BUILD
index 7b9e92e29f..62f0e1d2c5 100644
--- a/BUILD
+++ b/BUILD
@@ -829,14 +829,18 @@ grpc_cc_library(
 grpc_cc_library(
     name = "grpc_lb_policy_grpclb",
     srcs = [
+        "src/core/ext/filters/client_channel/lb_policy/grpclb/client_load_reporting_filter.c",
         "src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.c",
         "src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel.c",
+        "src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_client_stats.c",
         "src/core/ext/filters/client_channel/lb_policy/grpclb/load_balancer_api.c",
         "src/core/ext/filters/client_channel/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.c",
     ],
     hdrs = [
+        "src/core/ext/filters/client_channel/lb_policy/grpclb/client_load_reporting_filter.h",
         "src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.h",
         "src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel.h",
+        "src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_client_stats.h",
         "src/core/ext/filters/client_channel/lb_policy/grpclb/load_balancer_api.h",
         "src/core/ext/filters/client_channel/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.h",
     ],
@@ -853,14 +857,18 @@ grpc_cc_library(
 grpc_cc_library(
     name = "grpc_lb_policy_grpclb_secure",
     srcs = [
+        "src/core/ext/filters/client_channel/lb_policy/grpclb/client_load_reporting_filter.c",
         "src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.c",
         "src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel_secure.c",
+        "src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_client_stats.c",
         "src/core/ext/filters/client_channel/lb_policy/grpclb/load_balancer_api.c",
         "src/core/ext/filters/client_channel/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.c",
     ],
     hdrs = [
+        "src/core/ext/filters/client_channel/lb_policy/grpclb/client_load_reporting_filter.h",
         "src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.h",
         "src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel.h",
+        "src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_client_stats.h",
         "src/core/ext/filters/client_channel/lb_policy/grpclb/load_balancer_api.h",
         "src/core/ext/filters/client_channel/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.h",
     ],
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 325344a81c..f6c5f9e56d 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1121,8 +1121,10 @@ add_library(grpc
   src/core/ext/transport/chttp2/server/insecure/server_chttp2_posix.c
   src/core/ext/transport/chttp2/client/insecure/channel_create.c
   src/core/ext/transport/chttp2/client/insecure/channel_create_posix.c
+  src/core/ext/filters/client_channel/lb_policy/grpclb/client_load_reporting_filter.c
   src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.c
   src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel_secure.c
+  src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_client_stats.c
   src/core/ext/filters/client_channel/lb_policy/grpclb/load_balancer_api.c
   src/core/ext/filters/client_channel/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.c
   third_party/nanopb/pb_common.c
@@ -1991,8 +1993,10 @@ add_library(grpc_unsecure
   src/core/ext/filters/client_channel/resolver/sockaddr/sockaddr_resolver.c
   src/core/ext/filters/load_reporting/load_reporting.c
   src/core/ext/filters/load_reporting/load_reporting_filter.c
+  src/core/ext/filters/client_channel/lb_policy/grpclb/client_load_reporting_filter.c
   src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.c
   src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel.c
+  src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_client_stats.c
   src/core/ext/filters/client_channel/lb_policy/grpclb/load_balancer_api.c
   src/core/ext/filters/client_channel/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.c
   third_party/nanopb/pb_common.c
diff --git a/Makefile b/Makefile
index 4597b6fe97..993fd66aad 100644
--- a/Makefile
+++ b/Makefile
@@ -3104,8 +3104,10 @@ LIBGRPC_SRC = \
     src/core/ext/transport/chttp2/server/insecure/server_chttp2_posix.c \
     src/core/ext/transport/chttp2/client/insecure/channel_create.c \
     src/core/ext/transport/chttp2/client/insecure/channel_create_posix.c \
+    src/core/ext/filters/client_channel/lb_policy/grpclb/client_load_reporting_filter.c \
     src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.c \
     src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel_secure.c \
+    src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_client_stats.c \
     src/core/ext/filters/client_channel/lb_policy/grpclb/load_balancer_api.c \
     src/core/ext/filters/client_channel/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.c \
     third_party/nanopb/pb_common.c \
@@ -3943,8 +3945,10 @@ LIBGRPC_UNSECURE_SRC = \
     src/core/ext/filters/client_channel/resolver/sockaddr/sockaddr_resolver.c \
     src/core/ext/filters/load_reporting/load_reporting.c \
     src/core/ext/filters/load_reporting/load_reporting_filter.c \
+    src/core/ext/filters/client_channel/lb_policy/grpclb/client_load_reporting_filter.c \
     src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.c \
     src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel.c \
+    src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_client_stats.c \
     src/core/ext/filters/client_channel/lb_policy/grpclb/load_balancer_api.c \
     src/core/ext/filters/client_channel/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.c \
     third_party/nanopb/pb_common.c \
diff --git a/binding.gyp b/binding.gyp
index 582c61282f..19724f544b 100644
--- a/binding.gyp
+++ b/binding.gyp
@@ -855,8 +855,10 @@
         'src/core/ext/transport/chttp2/server/insecure/server_chttp2_posix.c',
         'src/core/ext/transport/chttp2/client/insecure/channel_create.c',
         'src/core/ext/transport/chttp2/client/insecure/channel_create_posix.c',
+        'src/core/ext/filters/client_channel/lb_policy/grpclb/client_load_reporting_filter.c',
         'src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.c',
         'src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel_secure.c',
+        'src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_client_stats.c',
         'src/core/ext/filters/client_channel/lb_policy/grpclb/load_balancer_api.c',
         'src/core/ext/filters/client_channel/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.c',
         'third_party/nanopb/pb_common.c',
diff --git a/build.yaml b/build.yaml
index 4cfa75cae1..865beab481 100644
--- a/build.yaml
+++ b/build.yaml
@@ -488,13 +488,17 @@ filegroups:
   - grpc_base
 - name: grpc_lb_policy_grpclb
   headers:
+  - src/core/ext/filters/client_channel/lb_policy/grpclb/client_load_reporting_filter.h
   - src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.h
   - src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel.h
+  - src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_client_stats.h
   - src/core/ext/filters/client_channel/lb_policy/grpclb/load_balancer_api.h
   - src/core/ext/filters/client_channel/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.h
   src:
+  - src/core/ext/filters/client_channel/lb_policy/grpclb/client_load_reporting_filter.c
   - src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.c
   - src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel.c
+  - src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_client_stats.c
   - src/core/ext/filters/client_channel/lb_policy/grpclb/load_balancer_api.c
   - src/core/ext/filters/client_channel/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.c
   plugin: grpc_lb_policy_grpclb
@@ -504,13 +508,17 @@ filegroups:
   - nanopb
 - name: grpc_lb_policy_grpclb_secure
   headers:
+  - src/core/ext/filters/client_channel/lb_policy/grpclb/client_load_reporting_filter.h
   - src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.h
   - src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel.h
+  - src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_client_stats.h
   - src/core/ext/filters/client_channel/lb_policy/grpclb/load_balancer_api.h
   - src/core/ext/filters/client_channel/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.h
   src:
+  - src/core/ext/filters/client_channel/lb_policy/grpclb/client_load_reporting_filter.c
   - src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.c
   - src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel_secure.c
+  - src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_client_stats.c
   - src/core/ext/filters/client_channel/lb_policy/grpclb/load_balancer_api.c
   - src/core/ext/filters/client_channel/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.c
   plugin: grpc_lb_policy_grpclb
diff --git a/config.m4 b/config.m4
index bbd667c9ec..1c0c6d92fc 100644
--- a/config.m4
+++ b/config.m4
@@ -291,8 +291,10 @@ if test "$PHP_GRPC" != "no"; then
     src/core/ext/transport/chttp2/server/insecure/server_chttp2_posix.c \
     src/core/ext/transport/chttp2/client/insecure/channel_create.c \
     src/core/ext/transport/chttp2/client/insecure/channel_create_posix.c \
+    src/core/ext/filters/client_channel/lb_policy/grpclb/client_load_reporting_filter.c \
     src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.c \
     src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel_secure.c \
+    src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_client_stats.c \
     src/core/ext/filters/client_channel/lb_policy/grpclb/load_balancer_api.c \
     src/core/ext/filters/client_channel/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.c \
     third_party/nanopb/pb_common.c \
diff --git a/gRPC-Core.podspec b/gRPC-Core.podspec
index 07755ac727..241eba01dd 100644
--- a/gRPC-Core.podspec
+++ b/gRPC-Core.podspec
@@ -434,8 +434,10 @@ Pod::Spec.new do |s|
                       'src/core/ext/filters/client_channel/uri_parser.h',
                       'src/core/ext/filters/deadline/deadline_filter.h',
                       'src/core/ext/transport/chttp2/client/chttp2_connector.h',
+                      'src/core/ext/filters/client_channel/lb_policy/grpclb/client_load_reporting_filter.h',
                       'src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.h',
                       'src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel.h',
+                      'src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_client_stats.h',
                       'src/core/ext/filters/client_channel/lb_policy/grpclb/load_balancer_api.h',
                       'src/core/ext/filters/client_channel/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.h',
                       'third_party/nanopb/pb.h',
@@ -668,8 +670,10 @@ Pod::Spec.new do |s|
                       'src/core/ext/transport/chttp2/server/insecure/server_chttp2_posix.c',
                       'src/core/ext/transport/chttp2/client/insecure/channel_create.c',
                       'src/core/ext/transport/chttp2/client/insecure/channel_create_posix.c',
+                      'src/core/ext/filters/client_channel/lb_policy/grpclb/client_load_reporting_filter.c',
                       'src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.c',
                       'src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel_secure.c',
+                      'src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_client_stats.c',
                       'src/core/ext/filters/client_channel/lb_policy/grpclb/load_balancer_api.c',
                       'src/core/ext/filters/client_channel/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.c',
                       'third_party/nanopb/pb_common.c',
@@ -895,8 +899,10 @@ Pod::Spec.new do |s|
                               'src/core/ext/filters/client_channel/uri_parser.h',
                               'src/core/ext/filters/deadline/deadline_filter.h',
                               'src/core/ext/transport/chttp2/client/chttp2_connector.h',
+                              'src/core/ext/filters/client_channel/lb_policy/grpclb/client_load_reporting_filter.h',
                               'src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.h',
                               'src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel.h',
+                              'src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_client_stats.h',
                               'src/core/ext/filters/client_channel/lb_policy/grpclb/load_balancer_api.h',
                               'src/core/ext/filters/client_channel/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.h',
                               'third_party/nanopb/pb.h',
diff --git a/grpc.gemspec b/grpc.gemspec
index 1cd6d66335..b96f3cbab5 100755
--- a/grpc.gemspec
+++ b/grpc.gemspec
@@ -350,8 +350,10 @@ Gem::Specification.new do |s|
   s.files += %w( src/core/ext/filters/client_channel/uri_parser.h )
   s.files += %w( src/core/ext/filters/deadline/deadline_filter.h )
   s.files += %w( src/core/ext/transport/chttp2/client/chttp2_connector.h )
+  s.files += %w( src/core/ext/filters/client_channel/lb_policy/grpclb/client_load_reporting_filter.h )
   s.files += %w( src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.h )
   s.files += %w( src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel.h )
+  s.files += %w( src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_client_stats.h )
   s.files += %w( src/core/ext/filters/client_channel/lb_policy/grpclb/load_balancer_api.h )
   s.files += %w( src/core/ext/filters/client_channel/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.h )
   s.files += %w( third_party/nanopb/pb.h )
@@ -584,8 +586,10 @@ Gem::Specification.new do |s|
   s.files += %w( src/core/ext/transport/chttp2/server/insecure/server_chttp2_posix.c )
   s.files += %w( src/core/ext/transport/chttp2/client/insecure/channel_create.c )
   s.files += %w( src/core/ext/transport/chttp2/client/insecure/channel_create_posix.c )
+  s.files += %w( src/core/ext/filters/client_channel/lb_policy/grpclb/client_load_reporting_filter.c )
   s.files += %w( src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.c )
   s.files += %w( src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel_secure.c )
+  s.files += %w( src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_client_stats.c )
   s.files += %w( src/core/ext/filters/client_channel/lb_policy/grpclb/load_balancer_api.c )
   s.files += %w( src/core/ext/filters/client_channel/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.c )
   s.files += %w( third_party/nanopb/pb_common.c )
diff --git a/include/grpc++/impl/codegen/call.h b/include/grpc++/impl/codegen/call.h
index f334ba61d6..9fe2bbb75e 100644
--- a/include/grpc++/impl/codegen/call.h
+++ b/include/grpc++/impl/codegen/call.h
@@ -364,28 +364,6 @@ class CallOpRecvMessage {
   bool allow_not_getting_message_;
 };
 
-namespace CallOpGenericRecvMessageHelper {
-class DeserializeFunc {
- public:
-  virtual Status Deserialize(grpc_byte_buffer* buf) = 0;
-  virtual ~DeserializeFunc() {}
-};
-
-template <class R>
-class DeserializeFuncType final : public DeserializeFunc {
- public:
-  DeserializeFuncType(R* message) : message_(message) {}
-  Status Deserialize(grpc_byte_buffer* buf) override {
-    return SerializationTraits<R>::Deserialize(buf, message_);
-  }
-
-  ~DeserializeFuncType() override {}
-
- private:
-  R* message_;  // Not a managed pointer because management is external to this
-};
-}  // namespace CallOpGenericRecvMessageHelper
-
 class CallOpGenericRecvMessage {
  public:
   CallOpGenericRecvMessage()
@@ -393,11 +371,9 @@ class CallOpGenericRecvMessage {
 
   template <class R>
   void RecvMessage(R* message) {
-    // Use an explicit base class pointer to avoid resolution error in the
-    // following unique_ptr::reset for some old implementations.
-    CallOpGenericRecvMessageHelper::DeserializeFunc* func =
-        new CallOpGenericRecvMessageHelper::DeserializeFuncType<R>(message);
-    deserialize_.reset(func);
+    deserialize_ = [message](grpc_byte_buffer* buf) -> Status {
+      return SerializationTraits<R>::Deserialize(buf, message);
+    };
   }
 
   // Do not change status if no message is received.
@@ -420,7 +396,7 @@ class CallOpGenericRecvMessage {
     if (recv_buf_) {
       if (*status) {
         got_message = true;
-        *status = deserialize_->Deserialize(recv_buf_).ok();
+        *status = deserialize_(recv_buf_).ok();
       } else {
         got_message = false;
         g_core_codegen_interface->grpc_byte_buffer_destroy(recv_buf_);
@@ -431,11 +407,12 @@ class CallOpGenericRecvMessage {
         *status = false;
       }
     }
-    deserialize_.reset();
+    deserialize_ = DeserializeFunc();
   }
 
  private:
-  std::unique_ptr<CallOpGenericRecvMessageHelper::DeserializeFunc> deserialize_;
+  typedef std::function<Status(grpc_byte_buffer*)> DeserializeFunc;
+  DeserializeFunc deserialize_;
   grpc_byte_buffer* recv_buf_;
   bool allow_not_getting_message_;
 };
diff --git a/package.xml b/package.xml
index e7d67eca18..d47708efa4 100644
--- a/package.xml
+++ b/package.xml
@@ -359,8 +359,10 @@
     <file baseinstalldir="/" name="src/core/ext/filters/client_channel/uri_parser.h" role="src" />
     <file baseinstalldir="/" name="src/core/ext/filters/deadline/deadline_filter.h" role="src" />
     <file baseinstalldir="/" name="src/core/ext/transport/chttp2/client/chttp2_connector.h" role="src" />
+    <file baseinstalldir="/" name="src/core/ext/filters/client_channel/lb_policy/grpclb/client_load_reporting_filter.h" role="src" />
     <file baseinstalldir="/" name="src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.h" role="src" />
     <file baseinstalldir="/" name="src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel.h" role="src" />
+    <file baseinstalldir="/" name="src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_client_stats.h" role="src" />
     <file baseinstalldir="/" name="src/core/ext/filters/client_channel/lb_policy/grpclb/load_balancer_api.h" role="src" />
     <file baseinstalldir="/" name="src/core/ext/filters/client_channel/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.h" role="src" />
     <file baseinstalldir="/" name="third_party/nanopb/pb.h" role="src" />
@@ -593,8 +595,10 @@
     <file baseinstalldir="/" name="src/core/ext/transport/chttp2/server/insecure/server_chttp2_posix.c" role="src" />
     <file baseinstalldir="/" name="src/core/ext/transport/chttp2/client/insecure/channel_create.c" role="src" />
     <file baseinstalldir="/" name="src/core/ext/transport/chttp2/client/insecure/channel_create_posix.c" role="src" />
+    <file baseinstalldir="/" name="src/core/ext/filters/client_channel/lb_policy/grpclb/client_load_reporting_filter.c" role="src" />
     <file baseinstalldir="/" name="src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.c" role="src" />
     <file baseinstalldir="/" name="src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel_secure.c" role="src" />
+    <file baseinstalldir="/" name="src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_client_stats.c" role="src" />
     <file baseinstalldir="/" name="src/core/ext/filters/client_channel/lb_policy/grpclb/load_balancer_api.c" role="src" />
     <file baseinstalldir="/" name="src/core/ext/filters/client_channel/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.c" role="src" />
     <file baseinstalldir="/" name="third_party/nanopb/pb_common.c" role="src" />
diff --git a/src/core/ext/filters/client_channel/client_channel.c b/src/core/ext/filters/client_channel/client_channel.c
index 652d789ec4..3e14d3e789 100644
--- a/src/core/ext/filters/client_channel/client_channel.c
+++ b/src/core/ext/filters/client_channel/client_channel.c
@@ -789,6 +789,7 @@ typedef struct client_channel_call_data {
 
   bool pick_pending;
   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;
@@ -937,7 +938,8 @@ static void subchannel_ready_locked(grpc_exec_ctx *exec_ctx, void *arg,
         .path = calld->path,
         .start_time = calld->call_start_time,
         .deadline = calld->deadline,
-        .arena = calld->arena};
+        .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,
@@ -966,6 +968,7 @@ 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;
   grpc_closure closure;
@@ -977,7 +980,8 @@ typedef struct {
 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_closure *on_ready);
+    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) {
@@ -987,9 +991,10 @@ static void continue_picking_locked(grpc_exec_ctx *exec_ctx, void *arg,
   } else if (error != GRPC_ERROR_NONE) {
     grpc_closure_sched(exec_ctx, cpa->on_ready, GRPC_ERROR_REF(error));
   } else {
-    if (pick_subchannel_locked(exec_ctx, cpa->elem, cpa->initial_metadata,
-                               cpa->initial_metadata_flags,
-                               cpa->connected_subchannel, cpa->on_ready)) {
+    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);
     }
   }
@@ -1021,7 +1026,9 @@ static void cancel_pick_locked(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
 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_closure *on_ready) {
+    grpc_connected_subchannel **connected_subchannel,
+    grpc_call_context_element *subchannel_call_context,
+    grpc_closure *on_ready) {
   GPR_TIMER_BEGIN("pick_subchannel", 0);
 
   channel_data *chand = elem->channel_data;
@@ -1065,8 +1072,8 @@ static bool pick_subchannel_locked(
     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, NULL,
-        &w_on_pick_arg->wrapper_closure);
+        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,
@@ -1089,6 +1096,7 @@ static bool pick_subchannel_locked(
     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,
@@ -1169,7 +1177,8 @@ static void start_transport_stream_op_batch_locked_inner(
             exec_ctx, elem,
             op->payload->send_initial_metadata.send_initial_metadata,
             op->payload->send_initial_metadata.send_initial_metadata_flags,
-            &calld->connected_subchannel, &calld->next_step)) {
+            &calld->connected_subchannel, calld->subchannel_call_context,
+            &calld->next_step)) {
       calld->pick_pending = false;
       GRPC_CALL_STACK_UNREF(exec_ctx, calld->owning_call, "pick_subchannel");
     } else {
@@ -1185,7 +1194,8 @@ static void start_transport_stream_op_batch_locked_inner(
         .path = calld->path,
         .start_time = calld->call_start_time,
         .deadline = calld->deadline,
-        .arena = calld->arena};
+        .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,
@@ -1340,6 +1350,12 @@ static void cc_destroy_call_elem(grpc_exec_ctx *exec_ctx,
     GRPC_CONNECTED_SUBCHANNEL_UNREF(exec_ctx, calld->connected_subchannel,
                                     "picked");
   }
+  for (size_t i = 0; i < GRPC_CONTEXT_COUNT; ++i) {
+    if (calld->subchannel_call_context[i].value != NULL) {
+      calld->subchannel_call_context[i].destroy(
+          calld->subchannel_call_context[i].value);
+    }
+  }
   gpr_free(calld->waiting_ops);
   grpc_closure_sched(exec_ctx, then_schedule_closure, GRPC_ERROR_NONE);
 }
diff --git a/src/core/ext/filters/client_channel/lb_policy.c b/src/core/ext/filters/client_channel/lb_policy.c
index 2d31499d13..112ba40658 100644
--- a/src/core/ext/filters/client_channel/lb_policy.c
+++ b/src/core/ext/filters/client_channel/lb_policy.c
@@ -119,9 +119,10 @@ void grpc_lb_policy_weak_unref(grpc_exec_ctx *exec_ctx,
 int grpc_lb_policy_pick_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *policy,
                                const grpc_lb_policy_pick_args *pick_args,
                                grpc_connected_subchannel **target,
+                               grpc_call_context_element *context,
                                void **user_data, grpc_closure *on_complete) {
   return policy->vtable->pick_locked(exec_ctx, policy, pick_args, target,
-                                     user_data, on_complete);
+                                     context, user_data, on_complete);
 }
 
 void grpc_lb_policy_cancel_pick_locked(grpc_exec_ctx *exec_ctx,
diff --git a/src/core/ext/filters/client_channel/lb_policy.h b/src/core/ext/filters/client_channel/lb_policy.h
index 25427666ae..fefcb4912c 100644
--- a/src/core/ext/filters/client_channel/lb_policy.h
+++ b/src/core/ext/filters/client_channel/lb_policy.h
@@ -43,9 +43,6 @@
 typedef struct grpc_lb_policy grpc_lb_policy;
 typedef struct grpc_lb_policy_vtable grpc_lb_policy_vtable;
 
-typedef void (*grpc_lb_completion)(void *cb_arg, grpc_subchannel *subchannel,
-                                   grpc_status_code status, const char *errmsg);
-
 struct grpc_lb_policy {
   const grpc_lb_policy_vtable *vtable;
   gpr_atm ref_pair;
@@ -76,7 +73,8 @@ struct grpc_lb_policy_vtable {
   /** \see grpc_lb_policy_pick */
   int (*pick_locked)(grpc_exec_ctx *exec_ctx, grpc_lb_policy *policy,
                      const grpc_lb_policy_pick_args *pick_args,
-                     grpc_connected_subchannel **target, void **user_data,
+                     grpc_connected_subchannel **target,
+                     grpc_call_context_element *context, void **user_data,
                      grpc_closure *on_complete);
 
   /** \see grpc_lb_policy_cancel_pick */
@@ -156,6 +154,8 @@ void grpc_lb_policy_init(grpc_lb_policy *policy,
     \a target will be set to the selected subchannel, or NULL on failure.
     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
+    call, if needed.
 
     If the pick succeeds and a result is known immediately, a non-zero
     value will be returned.  Otherwise, \a on_complete will be invoked
@@ -167,6 +167,7 @@ void grpc_lb_policy_init(grpc_lb_policy *policy,
 int grpc_lb_policy_pick_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *policy,
                                const grpc_lb_policy_pick_args *pick_args,
                                grpc_connected_subchannel **target,
+                               grpc_call_context_element *context,
                                void **user_data, grpc_closure *on_complete);
 
 /** Perform a connected subchannel ping (see \a grpc_connected_subchannel_ping)
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
new file mode 100644
index 0000000000..67baa46de7
--- /dev/null
+++ b/src/core/ext/filters/client_channel/lb_policy/grpclb/client_load_reporting_filter.c
@@ -0,0 +1,153 @@
+/*
+ *
+ * Copyright 2017, 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/ext/filters/client_channel/lb_policy/grpclb/client_load_reporting_filter.h"
+
+#include <grpc/support/atm.h>
+#include <grpc/support/log.h>
+
+#include "src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_client_stats.h"
+#include "src/core/lib/iomgr/error.h"
+#include "src/core/lib/profiling/timers.h"
+
+static grpc_error *init_channel_elem(grpc_exec_ctx *exec_ctx,
+                                     grpc_channel_element *elem,
+                                     grpc_channel_element_args *args) {
+  return GRPC_ERROR_NONE;
+}
+
+static void destroy_channel_elem(grpc_exec_ctx *exec_ctx,
+                                 grpc_channel_element *elem) {}
+
+typedef struct {
+  // Stats object to update.
+  grpc_grpclb_client_stats *client_stats;
+  // State for intercepting send_initial_metadata.
+  grpc_closure on_complete_for_send;
+  grpc_closure *original_on_complete_for_send;
+  bool send_initial_metadata_succeeded;
+  // State for intercepting recv_initial_metadata.
+  grpc_closure recv_initial_metadata_ready;
+  grpc_closure *original_recv_initial_metadata_ready;
+  bool recv_initial_metadata_succeeded;
+} call_data;
+
+static void on_complete_for_send(grpc_exec_ctx *exec_ctx, void *arg,
+                                 grpc_error *error) {
+  call_data *calld = arg;
+  if (error == GRPC_ERROR_NONE) {
+    calld->send_initial_metadata_succeeded = true;
+  }
+  grpc_closure_run(exec_ctx, calld->original_on_complete_for_send,
+                   GRPC_ERROR_REF(error));
+}
+
+static void recv_initial_metadata_ready(grpc_exec_ctx *exec_ctx, void *arg,
+                                        grpc_error *error) {
+  call_data *calld = arg;
+  if (error == GRPC_ERROR_NONE) {
+    calld->recv_initial_metadata_succeeded = true;
+  }
+  grpc_closure_run(exec_ctx, calld->original_recv_initial_metadata_ready,
+                   GRPC_ERROR_REF(error));
+}
+
+static grpc_error *init_call_elem(grpc_exec_ctx *exec_ctx,
+                                  grpc_call_element *elem,
+                                  const grpc_call_element_args *args) {
+  call_data *calld = elem->call_data;
+  // Get stats object from context and take a ref.
+  GPR_ASSERT(args->context != NULL);
+  GPR_ASSERT(args->context[GRPC_GRPCLB_CLIENT_STATS].value != NULL);
+  calld->client_stats = grpc_grpclb_client_stats_ref(
+      args->context[GRPC_GRPCLB_CLIENT_STATS].value);
+  // Record call started.
+  grpc_grpclb_client_stats_add_call_started(calld->client_stats);
+  return GRPC_ERROR_NONE;
+}
+
+static void destroy_call_elem(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
+                              const grpc_call_final_info *final_info,
+                              grpc_closure *ignored) {
+  call_data *calld = elem->call_data;
+  // Record call finished, optionally setting client_failed_to_send and
+  // received.
+  grpc_grpclb_client_stats_add_call_finished(
+      false /* drop_for_rate_limiting */, false /* drop_for_load_balancing */,
+      !calld->send_initial_metadata_succeeded /* client_failed_to_send */,
+      calld->recv_initial_metadata_succeeded /* known_received */,
+      calld->client_stats);
+  // All done, so unref the stats object.
+  grpc_grpclb_client_stats_unref(calld->client_stats);
+}
+
+static void 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;
+  GPR_TIMER_BEGIN("clr_start_transport_stream_op_batch", 0);
+  // 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_schedule_on_exec_ctx);
+    batch->on_complete = &calld->on_complete_for_send;
+  }
+  // Intercept recv_initial_metadata.
+  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,
+                      recv_initial_metadata_ready, calld,
+                      grpc_schedule_on_exec_ctx);
+    batch->payload->recv_initial_metadata.recv_initial_metadata_ready =
+        &calld->recv_initial_metadata_ready;
+  }
+  // Chain to next filter.
+  grpc_call_next_op(exec_ctx, elem, batch);
+  GPR_TIMER_END("clr_start_transport_stream_op_batch", 0);
+}
+
+const grpc_channel_filter grpc_client_load_reporting_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,  // sizeof(channel_data)
+    init_channel_elem,
+    destroy_channel_elem,
+    grpc_call_next_get_peer,
+    grpc_channel_next_get_info,
+    "client_load_reporting"};
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
new file mode 100644
index 0000000000..28b313d874
--- /dev/null
+++ b/src/core/ext/filters/client_channel/lb_policy/grpclb/client_load_reporting_filter.h
@@ -0,0 +1,42 @@
+/*
+ *
+ * Copyright 2017, 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_EXT_FILTERS_CLIENT_CHANNEL_LB_POLICY_GRPCLB_CLIENT_LOAD_REPORTING_FILTER_H
+#define GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_LB_POLICY_GRPCLB_CLIENT_LOAD_REPORTING_FILTER_H
+
+#include "src/core/lib/channel/channel_stack.h"
+
+extern const grpc_channel_filter grpc_client_load_reporting_filter;
+
+#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_LB_POLICY_GRPCLB_CLIENT_LOAD_REPORTING_FILTER_H \
+          */
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 9e158a94ad..37468101f0 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
@@ -108,13 +108,16 @@
 
 #include "src/core/ext/filters/client_channel/client_channel.h"
 #include "src/core/ext/filters/client_channel/client_channel_factory.h"
+#include "src/core/ext/filters/client_channel/lb_policy/grpclb/client_load_reporting_filter.h"
 #include "src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.h"
 #include "src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel.h"
+#include "src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_client_stats.h"
 #include "src/core/ext/filters/client_channel/lb_policy/grpclb/load_balancer_api.h"
 #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/lib/channel/channel_args.h"
+#include "src/core/lib/channel/channel_stack.h"
 #include "src/core/lib/iomgr/combiner.h"
 #include "src/core/lib/iomgr/sockaddr.h"
 #include "src/core/lib/iomgr/sockaddr_utils.h"
@@ -126,6 +129,7 @@
 #include "src/core/lib/support/string.h"
 #include "src/core/lib/surface/call.h"
 #include "src/core/lib/surface/channel.h"
+#include "src/core/lib/surface/channel_init.h"
 #include "src/core/lib/transport/static_metadata.h"
 
 #define GRPC_GRPCLB_MIN_CONNECT_TIMEOUT_SECONDS 20
@@ -147,6 +151,10 @@ static grpc_error *initial_metadata_add_lb_token(
                                       lb_token_mdelem_storage, lb_token);
 }
 
+static void destroy_client_stats(void *arg) {
+  grpc_grpclb_client_stats_unref(arg);
+}
+
 typedef struct wrapped_rr_closure_arg {
   /* the closure instance using this struct as argument */
   grpc_closure wrapper_closure;
@@ -163,6 +171,13 @@ typedef struct wrapped_rr_closure_arg {
    * initial metadata */
   grpc_connected_subchannel **target;
 
+  /* the context to be populated for the subchannel call */
+  grpc_call_context_element *context;
+
+  /* Stats for client-side load reporting. Note that this holds a
+   * reference, which must be either passed on via context or unreffed. */
+  grpc_grpclb_client_stats *client_stats;
+
   /* the LB token associated with the pick */
   grpc_mdelem lb_token;
 
@@ -202,6 +217,12 @@ static void wrapped_rr_closure(grpc_exec_ctx *exec_ctx, void *arg,
                 (void *)*wc_arg->target, (void *)wc_arg->rr_policy);
         abort();
       }
+      // 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;
+    } else {
+      grpc_grpclb_client_stats_unref(wc_arg->client_stats);
     }
     if (grpc_lb_glb_trace) {
       gpr_log(GPR_INFO, "Unreffing RR %p", (void *)wc_arg->rr_policy);
@@ -237,6 +258,7 @@ typedef struct pending_pick {
 static void add_pending_pick(pending_pick **root,
                              const grpc_lb_policy_pick_args *pick_args,
                              grpc_connected_subchannel **target,
+                             grpc_call_context_element *context,
                              grpc_closure *on_complete) {
   pending_pick *pp = gpr_zalloc(sizeof(*pp));
   pp->next = *root;
@@ -244,6 +266,7 @@ static void add_pending_pick(pending_pick **root,
   pp->target = target;
   pp->wrapped_on_complete_arg.wrapped_closure = on_complete;
   pp->wrapped_on_complete_arg.target = target;
+  pp->wrapped_on_complete_arg.context = context;
   pp->wrapped_on_complete_arg.initial_metadata = pick_args->initial_metadata;
   pp->wrapped_on_complete_arg.lb_token_mdelem_storage =
       pick_args->lb_token_mdelem_storage;
@@ -316,6 +339,10 @@ typedef struct glb_lb_policy {
   /************************************************************/
   /*  client data associated with the LB server communication */
   /************************************************************/
+
+  /* Finished sending initial request. */
+  grpc_closure lb_on_sent_initial_request;
+
   /* Status from the LB server has been received. This signals the end of the LB
    * call. */
   grpc_closure lb_on_server_status_received;
@@ -348,6 +375,23 @@ typedef struct glb_lb_policy {
 
   /** LB call retry timer */
   grpc_timer lb_call_retry_timer;
+
+  bool initial_request_sent;
+  bool seen_initial_response;
+
+  /* Stats for client-side load reporting. Should be unreffed and
+   * recreated whenever lb_call is replaced. */
+  grpc_grpclb_client_stats *client_stats;
+  /* Interval and timer for next client load report. */
+  gpr_timespec client_stats_report_interval;
+  grpc_timer client_load_report_timer;
+  bool client_load_report_timer_pending;
+  bool last_client_load_report_counters_were_zero;
+  /* Closure used for either the load report timer or the callback for
+   * completion of sending the load report. */
+  grpc_closure client_load_report_closure;
+  /* Client load report message payload. */
+  grpc_byte_buffer *client_load_report_payload;
 } glb_lb_policy;
 
 /* Keeps track and reacts to changes in connectivity of the RR instance */
@@ -552,8 +596,8 @@ static bool pick_from_internal_rr_locked(
     grpc_connected_subchannel **target, wrapped_rr_closure_arg *wc_arg) {
   GPR_ASSERT(rr_policy != NULL);
   const bool pick_done = grpc_lb_policy_pick_locked(
-      exec_ctx, rr_policy, pick_args, target, (void **)&wc_arg->lb_token,
-      &wc_arg->wrapper_closure);
+      exec_ctx, 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. */
     if (grpc_lb_glb_trace) {
@@ -567,7 +611,12 @@ static bool pick_from_internal_rr_locked(
                                   pick_args->lb_token_mdelem_storage,
                                   GRPC_MDELEM_REF(wc_arg->lb_token));
 
-    gpr_free(wc_arg);
+    // 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;
+
+    gpr_free(wc_arg->free_when_done);
   }
   /* else, the pending pick will be registered and taken care of by the
    * pending pick list inside the RR policy (glb_policy->rr_policy).
@@ -690,6 +739,8 @@ static void rr_handover_locked(grpc_exec_ctx *exec_ctx,
     glb_policy->pending_picks = pp->next;
     GRPC_LB_POLICY_REF(glb_policy->rr_policy, "rr_handover_pending_pick");
     pp->wrapped_on_complete_arg.rr_policy = glb_policy->rr_policy;
+    pp->wrapped_on_complete_arg.client_stats =
+        grpc_grpclb_client_stats_ref(glb_policy->client_stats);
     if (grpc_lb_glb_trace) {
       gpr_log(GPR_INFO, "Pending pick about to PICK from 0x%" PRIxPTR "",
               (intptr_t)glb_policy->rr_policy);
@@ -864,9 +915,18 @@ static grpc_lb_policy *glb_create(grpc_exec_ctx *exec_ctx,
   grpc_uri_destroy(uri);
 
   glb_policy->cc_factory = args->client_channel_factory;
-  glb_policy->args = grpc_channel_args_copy(args->args);
   GPR_ASSERT(glb_policy->cc_factory != NULL);
 
+  // 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";
+  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 =
@@ -880,6 +940,8 @@ static grpc_lb_policy *glb_create(grpc_exec_ctx *exec_ctx,
   grpc_channel_args_destroy(exec_ctx, lb_channel_args);
   gpr_free(lb_service_target_addresses);
   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;
   }
@@ -895,6 +957,9 @@ static void glb_destroy(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol) {
   GPR_ASSERT(glb_policy->pending_pings == NULL);
   gpr_free((void *)glb_policy->server_name);
   grpc_channel_args_destroy(exec_ctx, glb_policy->args);
+  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);
@@ -1011,7 +1076,8 @@ static void glb_exit_idle_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol) {
 
 static int glb_pick_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol,
                            const grpc_lb_policy_pick_args *pick_args,
-                           grpc_connected_subchannel **target, void **user_data,
+                           grpc_connected_subchannel **target,
+                           grpc_call_context_element *context, void **user_data,
                            grpc_closure *on_complete) {
   if (pick_args->lb_token_mdelem_storage == NULL) {
     *target = NULL;
@@ -1039,6 +1105,10 @@ static int glb_pick_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol,
                       grpc_schedule_on_exec_ctx);
     wc_arg->rr_policy = glb_policy->rr_policy;
     wc_arg->target = target;
+    wc_arg->context = context;
+    GPR_ASSERT(glb_policy->client_stats != NULL);
+    wc_arg->client_stats =
+        grpc_grpclb_client_stats_ref(glb_policy->client_stats);
     wc_arg->wrapped_closure = on_complete;
     wc_arg->lb_token_mdelem_storage = pick_args->lb_token_mdelem_storage;
     wc_arg->initial_metadata = pick_args->initial_metadata;
@@ -1052,7 +1122,7 @@ static int glb_pick_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol,
               "picks",
               (void *)(glb_policy));
     }
-    add_pending_pick(&glb_policy->pending_picks, pick_args, target,
+    add_pending_pick(&glb_policy->pending_picks, pick_args, target, context,
                      on_complete);
 
     if (!glb_policy->started_picking) {
@@ -1093,6 +1163,104 @@ static void glb_notify_on_state_change_locked(grpc_exec_ctx *exec_ctx,
       exec_ctx, &glb_policy->state_tracker, current, notify);
 }
 
+static void send_client_load_report_locked(grpc_exec_ctx *exec_ctx, void *arg,
+                                           grpc_error *error);
+
+static void schedule_next_client_load_report(grpc_exec_ctx *exec_ctx,
+                                             glb_lb_policy *glb_policy) {
+  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,
+                    send_client_load_report_locked, glb_policy,
+                    grpc_combiner_scheduler(glb_policy->base.combiner, false));
+  grpc_timer_init(exec_ctx, &glb_policy->client_load_report_timer,
+                  next_client_load_report_time,
+                  &glb_policy->client_load_report_closure, now);
+}
+
+static void client_load_report_done_locked(grpc_exec_ctx *exec_ctx, void *arg,
+                                           grpc_error *error) {
+  glb_lb_policy *glb_policy = arg;
+  grpc_byte_buffer_destroy(glb_policy->client_load_report_payload);
+  glb_policy->client_load_report_payload = NULL;
+  if (error != GRPC_ERROR_NONE || glb_policy->lb_call == NULL) {
+    glb_policy->client_load_report_timer_pending = false;
+    GRPC_LB_POLICY_WEAK_UNREF(exec_ctx, &glb_policy->base,
+                              "client_load_report");
+    return;
+  }
+  schedule_next_client_load_report(exec_ctx, glb_policy);
+}
+
+static void do_send_client_load_report_locked(grpc_exec_ctx *exec_ctx,
+                                              glb_lb_policy *glb_policy) {
+  grpc_op op;
+  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,
+                    client_load_report_done_locked, glb_policy,
+                    grpc_combiner_scheduler(glb_policy->base.combiner, false));
+  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);
+  GPR_ASSERT(GRPC_CALL_OK == call_error);
+}
+
+static bool load_report_counters_are_zero(grpc_grpclb_request *request) {
+  return request->client_stats.num_calls_started == 0 &&
+         request->client_stats.num_calls_finished == 0 &&
+         request->client_stats.num_calls_finished_with_drop_for_rate_limiting ==
+             0 &&
+         request->client_stats
+                 .num_calls_finished_with_drop_for_load_balancing == 0 &&
+         request->client_stats.num_calls_finished_with_client_failed_to_send ==
+             0 &&
+         request->client_stats.num_calls_finished_known_received == 0;
+}
+
+static void send_client_load_report_locked(grpc_exec_ctx *exec_ctx, void *arg,
+                                           grpc_error *error) {
+  glb_lb_policy *glb_policy = arg;
+  if (error == GRPC_ERROR_CANCELLED || glb_policy->lb_call == NULL) {
+    glb_policy->client_load_report_timer_pending = false;
+    GRPC_LB_POLICY_WEAK_UNREF(exec_ctx, &glb_policy->base,
+                              "client_load_report");
+    return;
+  }
+  // Construct message payload.
+  GPR_ASSERT(glb_policy->client_load_report_payload == NULL);
+  grpc_grpclb_request *request =
+      grpc_grpclb_load_report_request_create(glb_policy->client_stats);
+  // Skip client load report if the counters were all zero in the last
+  // report and they are still zero in this one.
+  if (load_report_counters_are_zero(request)) {
+    if (glb_policy->last_client_load_report_counters_were_zero) {
+      grpc_grpclb_request_destroy(request);
+      schedule_next_client_load_report(exec_ctx, glb_policy);
+      return;
+    }
+    glb_policy->last_client_load_report_counters_were_zero = true;
+  } else {
+    glb_policy->last_client_load_report_counters_were_zero = false;
+  }
+  grpc_slice request_payload_slice = grpc_grpclb_request_encode(request);
+  glb_policy->client_load_report_payload =
+      grpc_raw_byte_buffer_create(&request_payload_slice, 1);
+  grpc_slice_unref_internal(exec_ctx, request_payload_slice);
+  grpc_grpclb_request_destroy(request);
+  // If we've already sent the initial request, then we can go ahead and
+  // sent the load report.  Otherwise, we need to wait until the initial
+  // request has been sent to send this
+  // (see lb_on_sent_initial_request_locked() below).
+  if (glb_policy->initial_request_sent) {
+    do_send_client_load_report_locked(exec_ctx, glb_policy);
+  }
+}
+
+static void lb_on_sent_initial_request_locked(grpc_exec_ctx *exec_ctx,
+                                              void *arg, grpc_error *error);
 static void lb_on_server_status_received_locked(grpc_exec_ctx *exec_ctx,
                                                 void *arg, grpc_error *error);
 static void lb_on_response_received_locked(grpc_exec_ctx *exec_ctx, void *arg,
@@ -1114,6 +1282,11 @@ static void lb_call_init_locked(grpc_exec_ctx *exec_ctx,
       &host, glb_policy->deadline, NULL);
   grpc_slice_unref_internal(exec_ctx, host);
 
+  if (glb_policy->client_stats != NULL) {
+    grpc_grpclb_client_stats_unref(glb_policy->client_stats);
+  }
+  glb_policy->client_stats = grpc_grpclb_client_stats_create();
+
   grpc_metadata_array_init(&glb_policy->lb_initial_metadata_recv);
   grpc_metadata_array_init(&glb_policy->lb_trailing_metadata_recv);
 
@@ -1125,6 +1298,9 @@ 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,
+                    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,
                     lb_on_server_status_received_locked, glb_policy,
                     grpc_combiner_scheduler(glb_policy->base.combiner, false));
@@ -1138,6 +1314,10 @@ static void lb_call_init_locked(grpc_exec_ctx *exec_ctx,
                    GRPC_GRPCLB_RECONNECT_JITTER,
                    GRPC_GRPCLB_MIN_CONNECT_TIMEOUT_SECONDS * 1000,
                    GRPC_GRPCLB_RECONNECT_MAX_BACKOFF_SECONDS * 1000);
+
+  glb_policy->initial_request_sent = false;
+  glb_policy->seen_initial_response = false;
+  glb_policy->last_client_load_report_counters_were_zero = false;
 }
 
 static void lb_call_destroy_locked(grpc_exec_ctx *exec_ctx,
@@ -1151,6 +1331,10 @@ static void lb_call_destroy_locked(grpc_exec_ctx *exec_ctx,
 
   grpc_byte_buffer_destroy(glb_policy->lb_request_payload);
   grpc_slice_unref_internal(exec_ctx, glb_policy->lb_call_status_details);
+
+  if (!glb_policy->client_load_report_timer_pending) {
+    grpc_timer_cancel(exec_ctx, &glb_policy->client_load_report_timer);
+  }
 }
 
 /*
@@ -1179,21 +1363,27 @@ static void query_for_backends_locked(grpc_exec_ctx *exec_ctx,
   op->flags = 0;
   op->reserved = NULL;
   op++;
-
   op->op = GRPC_OP_RECV_INITIAL_METADATA;
   op->data.recv_initial_metadata.recv_initial_metadata =
       &glb_policy->lb_initial_metadata_recv;
   op->flags = 0;
   op->reserved = NULL;
   op++;
-
   GPR_ASSERT(glb_policy->lb_request_payload != NULL);
   op->op = GRPC_OP_SEND_MESSAGE;
   op->data.send_message.send_message = glb_policy->lb_request_payload;
   op->flags = 0;
   op->reserved = NULL;
   op++;
+  /* take a weak ref (won't prevent calling of \a glb_shutdown if the strong ref
+   * count goes to zero) to be unref'd in lb_on_sent_initial_request_locked() */
+  GRPC_LB_POLICY_WEAK_REF(&glb_policy->base, "lb_on_server_status_received");
+  call_error = grpc_call_start_batch_and_execute(
+      exec_ctx, glb_policy->lb_call, ops, (size_t)(op - ops),
+      &glb_policy->lb_on_sent_initial_request);
+  GPR_ASSERT(GRPC_CALL_OK == call_error);
 
+  op = ops;
   op->op = GRPC_OP_RECV_STATUS_ON_CLIENT;
   op->data.recv_status_on_client.trailing_metadata =
       &glb_policy->lb_trailing_metadata_recv;
@@ -1225,6 +1415,19 @@ static void query_for_backends_locked(grpc_exec_ctx *exec_ctx,
   GPR_ASSERT(GRPC_CALL_OK == call_error);
 }
 
+static void lb_on_sent_initial_request_locked(grpc_exec_ctx *exec_ctx,
+                                              void *arg, grpc_error *error) {
+  glb_lb_policy *glb_policy = arg;
+  glb_policy->initial_request_sent = true;
+  // If we attempted to send a client load report before the initial
+  // request was sent, send the load report now.
+  if (glb_policy->client_load_report_payload != NULL) {
+    do_send_client_load_report_locked(exec_ctx, glb_policy);
+  }
+  GRPC_LB_POLICY_WEAK_UNREF(exec_ctx, &glb_policy->base,
+                            "lb_on_response_received_locked");
+}
+
 static void lb_on_response_received_locked(grpc_exec_ctx *exec_ctx, void *arg,
                                            grpc_error *error) {
   glb_lb_policy *glb_policy = arg;
@@ -1240,58 +1443,91 @@ static void lb_on_response_received_locked(grpc_exec_ctx *exec_ctx, void *arg,
     grpc_byte_buffer_reader_init(&bbr, glb_policy->lb_response_payload);
     grpc_slice response_slice = grpc_byte_buffer_reader_readall(&bbr);
     grpc_byte_buffer_destroy(glb_policy->lb_response_payload);
-    grpc_grpclb_serverlist *serverlist =
-        grpc_grpclb_response_parse_serverlist(response_slice);
-    if (serverlist != NULL) {
-      GPR_ASSERT(glb_policy->lb_call != NULL);
-      grpc_slice_unref_internal(exec_ctx, response_slice);
-      if (grpc_lb_glb_trace) {
-        gpr_log(GPR_INFO, "Serverlist with %lu servers received",
-                (unsigned long)serverlist->num_servers);
-        for (size_t i = 0; i < serverlist->num_servers; ++i) {
-          grpc_resolved_address addr;
-          parse_server(serverlist->servers[i], &addr);
-          char *ipport;
-          grpc_sockaddr_to_string(&ipport, &addr, false);
-          gpr_log(GPR_INFO, "Serverlist[%lu]: %s", (unsigned long)i, ipport);
-          gpr_free(ipport);
+
+    grpc_grpclb_initial_response *response = NULL;
+    if (!glb_policy->seen_initial_response &&
+        (response = grpc_grpclb_initial_response_parse(response_slice)) !=
+            NULL) {
+      if (response->has_client_stats_report_interval) {
+        glb_policy->client_stats_report_interval =
+            gpr_time_max(gpr_time_from_seconds(1, GPR_TIMESPAN),
+                         grpc_grpclb_duration_to_timespec(
+                             &response->client_stats_report_interval));
+        if (grpc_lb_glb_trace) {
+          gpr_log(GPR_INFO,
+                  "received initial LB response message; "
+                  "client load reporting interval = %" PRId64 ".%09d sec",
+                  glb_policy->client_stats_report_interval.tv_sec,
+                  glb_policy->client_stats_report_interval.tv_nsec);
         }
+        /* take a weak ref (won't prevent calling of \a glb_shutdown() if the
+         * strong ref count goes to zero) to be unref'd in
+         * send_client_load_report() */
+        glb_policy->client_load_report_timer_pending = true;
+        GRPC_LB_POLICY_WEAK_REF(&glb_policy->base, "client_load_report");
+        schedule_next_client_load_report(exec_ctx, glb_policy);
+      } else if (grpc_lb_glb_trace) {
+        gpr_log(GPR_INFO,
+                "received initial LB response message; "
+                "client load reporting NOT enabled");
       }
+      grpc_grpclb_initial_response_destroy(response);
+      glb_policy->seen_initial_response = true;
+    } else {
+      grpc_grpclb_serverlist *serverlist =
+          grpc_grpclb_response_parse_serverlist(response_slice);
+      if (serverlist != NULL) {
+        GPR_ASSERT(glb_policy->lb_call != NULL);
+        if (grpc_lb_glb_trace) {
+          gpr_log(GPR_INFO, "Serverlist with %lu servers received",
+                  (unsigned long)serverlist->num_servers);
+          for (size_t i = 0; i < serverlist->num_servers; ++i) {
+            grpc_resolved_address addr;
+            parse_server(serverlist->servers[i], &addr);
+            char *ipport;
+            grpc_sockaddr_to_string(&ipport, &addr, false);
+            gpr_log(GPR_INFO, "Serverlist[%lu]: %s", (unsigned long)i, ipport);
+            gpr_free(ipport);
+          }
+        }
 
-      /* update serverlist */
-      if (serverlist->num_servers > 0) {
-        if (grpc_grpclb_serverlist_equals(glb_policy->serverlist, serverlist)) {
+        /* update serverlist */
+        if (serverlist->num_servers > 0) {
+          if (grpc_grpclb_serverlist_equals(glb_policy->serverlist,
+                                            serverlist)) {
+            if (grpc_lb_glb_trace) {
+              gpr_log(GPR_INFO,
+                      "Incoming server list identical to current, ignoring.");
+            }
+            grpc_grpclb_destroy_serverlist(serverlist);
+          } else { /* new serverlist */
+            if (glb_policy->serverlist != NULL) {
+              /* dispose of the old serverlist */
+              grpc_grpclb_destroy_serverlist(glb_policy->serverlist);
+            }
+            /* and update the copy in the glb_lb_policy instance. This
+             * serverlist instance will be destroyed either upon the next
+             * update or in glb_destroy() */
+            glb_policy->serverlist = serverlist;
+
+            rr_handover_locked(exec_ctx, glb_policy);
+          }
+        } else {
           if (grpc_lb_glb_trace) {
             gpr_log(GPR_INFO,
-                    "Incoming server list identical to current, ignoring.");
+                    "Received empty server list. Picks will stay pending until "
+                    "a response with > 0 servers is received");
           }
           grpc_grpclb_destroy_serverlist(serverlist);
-        } else { /* new serverlist */
-          if (glb_policy->serverlist != NULL) {
-            /* dispose of the old serverlist */
-            grpc_grpclb_destroy_serverlist(glb_policy->serverlist);
-          }
-          /* and update the copy in the glb_lb_policy instance. This serverlist
-           * instance will be destroyed either upon the next update or in
-           * glb_destroy() */
-          glb_policy->serverlist = serverlist;
-
-          rr_handover_locked(exec_ctx, glb_policy);
         }
-      } else {
-        if (grpc_lb_glb_trace) {
-          gpr_log(GPR_INFO,
-                  "Received empty server list. Picks will stay pending until a "
-                  "response with > 0 servers is received");
-        }
-        grpc_grpclb_destroy_serverlist(serverlist);
+      } else { /* serverlist == NULL */
+        gpr_log(GPR_ERROR, "Invalid LB response received: '%s'. Ignoring.",
+                grpc_dump_slice(response_slice, GPR_DUMP_ASCII | GPR_DUMP_HEX));
       }
-    } else { /* serverlist == NULL */
-      gpr_log(GPR_ERROR, "Invalid LB response received: '%s'. Ignoring.",
-              grpc_dump_slice(response_slice, GPR_DUMP_ASCII | GPR_DUMP_HEX));
-      grpc_slice_unref_internal(exec_ctx, response_slice);
     }
 
+    grpc_slice_unref_internal(exec_ctx, response_slice);
+
     if (!glb_policy->shutting_down) {
       /* keep listening for serverlist updates */
       op->op = GRPC_OP_RECV_MESSAGE;
@@ -1403,9 +1639,29 @@ grpc_lb_policy_factory *grpc_glb_lb_factory_create() {
 }
 
 /* Plugin registration */
+
+// Only add client_load_reporting filter if the grpclb LB policy is used.
+static bool maybe_add_client_load_reporting_filter(
+    grpc_exec_ctx *exec_ctx, grpc_channel_stack_builder *builder, void *arg) {
+  const grpc_channel_args *args =
+      grpc_channel_stack_builder_get_channel_arguments(builder);
+  const grpc_arg *channel_arg =
+      grpc_channel_args_find(args, GRPC_ARG_LB_POLICY_NAME);
+  if (channel_arg != NULL && channel_arg->type == GRPC_ARG_STRING &&
+      strcmp(channel_arg->value.string, "grpclb") == 0) {
+    return grpc_channel_stack_builder_append_filter(
+        builder, (const grpc_channel_filter *)arg, NULL, NULL);
+  }
+  return true;
+}
+
 void grpc_lb_policy_grpclb_init() {
   grpc_register_lb_policy(grpc_glb_lb_factory_create());
   grpc_register_tracer("glb", &grpc_lb_glb_trace);
+  grpc_channel_init_register_stage(GRPC_CLIENT_SUBCHANNEL,
+                                   GRPC_CHANNEL_INIT_BUILTIN_PRIORITY,
+                                   maybe_add_client_load_reporting_filter,
+                                   (void *)&grpc_client_load_reporting_filter);
 }
 
 void grpc_lb_policy_grpclb_shutdown() {}
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
new file mode 100644
index 0000000000..444c03b9aa
--- /dev/null
+++ b/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_client_stats.c
@@ -0,0 +1,133 @@
+/*
+ *
+ * Copyright 2017, 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/ext/filters/client_channel/lb_policy/grpclb/grpclb_client_stats.h"
+
+#include <grpc/support/alloc.h>
+#include <grpc/support/atm.h>
+#include <grpc/support/sync.h>
+#include <grpc/support/useful.h>
+
+#include "src/core/lib/channel/channel_args.h"
+
+#define GRPC_ARG_GRPCLB_CLIENT_STATS "grpc.grpclb_client_stats"
+
+struct grpc_grpclb_client_stats {
+  gpr_refcount refs;
+  gpr_atm num_calls_started;
+  gpr_atm num_calls_finished;
+  gpr_atm num_calls_finished_with_drop_for_rate_limiting;
+  gpr_atm num_calls_finished_with_drop_for_load_balancing;
+  gpr_atm num_calls_finished_with_client_failed_to_send;
+  gpr_atm num_calls_finished_known_received;
+};
+
+grpc_grpclb_client_stats* grpc_grpclb_client_stats_create() {
+  grpc_grpclb_client_stats* client_stats = gpr_zalloc(sizeof(*client_stats));
+  gpr_ref_init(&client_stats->refs, 1);
+  return client_stats;
+}
+
+grpc_grpclb_client_stats* grpc_grpclb_client_stats_ref(
+    grpc_grpclb_client_stats* client_stats) {
+  gpr_ref(&client_stats->refs);
+  return client_stats;
+}
+
+void grpc_grpclb_client_stats_unref(grpc_grpclb_client_stats* client_stats) {
+  if (gpr_unref(&client_stats->refs)) {
+    gpr_free(client_stats);
+  }
+}
+
+void grpc_grpclb_client_stats_add_call_started(
+    grpc_grpclb_client_stats* client_stats) {
+  gpr_atm_full_fetch_add(&client_stats->num_calls_started, (gpr_atm)1);
+}
+
+void grpc_grpclb_client_stats_add_call_finished(
+    bool finished_with_drop_for_rate_limiting,
+    bool finished_with_drop_for_load_balancing,
+    bool finished_with_client_failed_to_send, bool finished_known_received,
+    grpc_grpclb_client_stats* client_stats) {
+  gpr_atm_full_fetch_add(&client_stats->num_calls_finished, (gpr_atm)1);
+  if (finished_with_drop_for_rate_limiting) {
+    gpr_atm_full_fetch_add(
+        &client_stats->num_calls_finished_with_drop_for_rate_limiting,
+        (gpr_atm)1);
+  }
+  if (finished_with_drop_for_load_balancing) {
+    gpr_atm_full_fetch_add(
+        &client_stats->num_calls_finished_with_drop_for_load_balancing,
+        (gpr_atm)1);
+  }
+  if (finished_with_client_failed_to_send) {
+    gpr_atm_full_fetch_add(
+        &client_stats->num_calls_finished_with_client_failed_to_send,
+        (gpr_atm)1);
+  }
+  if (finished_known_received) {
+    gpr_atm_full_fetch_add(&client_stats->num_calls_finished_known_received,
+                           (gpr_atm)1);
+  }
+}
+
+static void atomic_get_and_reset_counter(int64_t* value, gpr_atm* counter) {
+  *value = (int64_t)gpr_atm_acq_load(counter);
+  gpr_atm_full_fetch_add(counter, (gpr_atm)(-*value));
+}
+
+void grpc_grpclb_client_stats_get(
+    grpc_grpclb_client_stats* client_stats, int64_t* num_calls_started,
+    int64_t* num_calls_finished,
+    int64_t* num_calls_finished_with_drop_for_rate_limiting,
+    int64_t* num_calls_finished_with_drop_for_load_balancing,
+    int64_t* num_calls_finished_with_client_failed_to_send,
+    int64_t* num_calls_finished_known_received) {
+  atomic_get_and_reset_counter(num_calls_started,
+                               &client_stats->num_calls_started);
+  atomic_get_and_reset_counter(num_calls_finished,
+                               &client_stats->num_calls_finished);
+  atomic_get_and_reset_counter(
+      num_calls_finished_with_drop_for_rate_limiting,
+      &client_stats->num_calls_finished_with_drop_for_rate_limiting);
+  atomic_get_and_reset_counter(
+      num_calls_finished_with_drop_for_load_balancing,
+      &client_stats->num_calls_finished_with_drop_for_load_balancing);
+  atomic_get_and_reset_counter(
+      num_calls_finished_with_client_failed_to_send,
+      &client_stats->num_calls_finished_with_client_failed_to_send);
+  atomic_get_and_reset_counter(
+      num_calls_finished_known_received,
+      &client_stats->num_calls_finished_known_received);
+}
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
new file mode 100644
index 0000000000..0af4a919f8
--- /dev/null
+++ b/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_client_stats.h
@@ -0,0 +1,65 @@
+/*
+ *
+ * Copyright 2017, 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_EXT_FILTERS_CLIENT_CHANNEL_LB_POLICY_GRPCLB_GRPCLB_CLIENT_STATS_H
+#define GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_LB_POLICY_GRPCLB_GRPCLB_CLIENT_STATS_H
+
+#include <stdbool.h>
+
+#include <grpc/impl/codegen/grpc_types.h>
+
+typedef struct grpc_grpclb_client_stats grpc_grpclb_client_stats;
+
+grpc_grpclb_client_stats* grpc_grpclb_client_stats_create();
+grpc_grpclb_client_stats* grpc_grpclb_client_stats_ref(
+    grpc_grpclb_client_stats* client_stats);
+void grpc_grpclb_client_stats_unref(grpc_grpclb_client_stats* client_stats);
+
+void grpc_grpclb_client_stats_add_call_started(
+    grpc_grpclb_client_stats* client_stats);
+void grpc_grpclb_client_stats_add_call_finished(
+    bool finished_with_drop_for_rate_limiting,
+    bool finished_with_drop_for_load_balancing,
+    bool finished_with_client_failed_to_send, bool finished_known_received,
+    grpc_grpclb_client_stats* client_stats);
+
+void grpc_grpclb_client_stats_get(
+    grpc_grpclb_client_stats* client_stats, int64_t* num_calls_started,
+    int64_t* num_calls_finished,
+    int64_t* num_calls_finished_with_drop_for_rate_limiting,
+    int64_t* num_calls_finished_with_drop_for_load_balancing,
+    int64_t* num_calls_finished_with_client_failed_to_send,
+    int64_t* num_calls_finished_known_received);
+
+#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_LB_POLICY_GRPCLB_GRPCLB_CLIENT_STATS_H \
+          */
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 87549b78f0..81b6932fae 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
@@ -80,15 +80,45 @@ static bool decode_serverlist(pb_istream_t *stream, const pb_field_t *field,
 
 grpc_grpclb_request *grpc_grpclb_request_create(const char *lb_service_name) {
   grpc_grpclb_request *req = gpr_malloc(sizeof(grpc_grpclb_request));
-
-  req->has_client_stats = 0; /* TODO(dgq): add support for stats once defined */
-  req->has_initial_request = 1;
-  req->initial_request.has_name = 1;
+  req->has_client_stats = false;
+  req->has_initial_request = true;
+  req->initial_request.has_name = true;
   strncpy(req->initial_request.name, lb_service_name,
           GRPC_GRPCLB_SERVICE_NAME_MAX_LENGTH);
   return req;
 }
 
+static void populate_timestamp(gpr_timespec timestamp,
+                               struct _grpc_lb_v1_Timestamp *timestamp_pb) {
+  timestamp_pb->has_seconds = true;
+  timestamp_pb->seconds = timestamp.tv_sec;
+  timestamp_pb->has_nanos = true;
+  timestamp_pb->nanos = timestamp.tv_nsec;
+}
+
+grpc_grpclb_request *grpc_grpclb_load_report_request_create(
+    grpc_grpclb_client_stats *client_stats) {
+  grpc_grpclb_request *req = gpr_zalloc(sizeof(grpc_grpclb_request));
+  req->has_client_stats = true;
+  req->client_stats.has_timestamp = true;
+  populate_timestamp(gpr_now(GPR_CLOCK_REALTIME), &req->client_stats.timestamp);
+  req->client_stats.has_num_calls_started = true;
+  req->client_stats.has_num_calls_finished = true;
+  req->client_stats.has_num_calls_finished_with_drop_for_rate_limiting = true;
+  req->client_stats.has_num_calls_finished_with_drop_for_load_balancing = true;
+  req->client_stats.has_num_calls_finished_with_client_failed_to_send = true;
+  req->client_stats.has_num_calls_finished_with_client_failed_to_send = true;
+  req->client_stats.has_num_calls_finished_known_received = true;
+  grpc_grpclb_client_stats_get(
+      client_stats, &req->client_stats.num_calls_started,
+      &req->client_stats.num_calls_finished,
+      &req->client_stats.num_calls_finished_with_drop_for_rate_limiting,
+      &req->client_stats.num_calls_finished_with_drop_for_load_balancing,
+      &req->client_stats.num_calls_finished_with_client_failed_to_send,
+      &req->client_stats.num_calls_finished_known_received);
+  return req;
+}
+
 grpc_slice grpc_grpclb_request_encode(const grpc_grpclb_request *request) {
   size_t encoded_length;
   pb_ostream_t sizestream;
@@ -122,6 +152,9 @@ grpc_grpclb_initial_response *grpc_grpclb_initial_response_parse(
     gpr_log(GPR_ERROR, "nanopb error: %s", PB_GET_ERROR(&stream));
     return NULL;
   }
+
+  if (!res.has_initial_response) return NULL;
+
   grpc_grpclb_initial_response *initial_res =
       gpr_malloc(sizeof(grpc_grpclb_initial_response));
   memcpy(initial_res, &res.initial_response,
@@ -243,6 +276,15 @@ int grpc_grpclb_duration_compare(const grpc_grpclb_duration *lhs,
   return 0;
 }
 
+gpr_timespec grpc_grpclb_duration_to_timespec(
+    grpc_grpclb_duration *duration_pb) {
+  gpr_timespec duration;
+  duration.tv_sec = duration_pb->has_seconds ? duration_pb->seconds : 0;
+  duration.tv_nsec = duration_pb->has_nanos ? duration_pb->nanos : 0;
+  duration.clock_type = GPR_TIMESPAN;
+  return duration;
+}
+
 void grpc_grpclb_initial_response_destroy(
     grpc_grpclb_initial_response *response) {
   gpr_free(response);
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 d014b8800c..06873821bd 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
@@ -36,6 +36,7 @@
 
 #include <grpc/slice_buffer.h>
 
+#include "src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_client_stats.h"
 #include "src/core/ext/filters/client_channel/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.h"
 #include "src/core/ext/filters/client_channel/lb_policy_factory.h"
 
@@ -58,6 +59,8 @@ typedef struct grpc_grpclb_serverlist {
 
 /** Create a request for a gRPC LB service under \a lb_service_name */
 grpc_grpclb_request *grpc_grpclb_request_create(const char *lb_service_name);
+grpc_grpclb_request *grpc_grpclb_load_report_request_create(
+    grpc_grpclb_client_stats *client_stats);
 
 /** Protocol Buffers v3-encode \a request */
 grpc_slice grpc_grpclb_request_encode(const grpc_grpclb_request *request);
@@ -93,6 +96,9 @@ void grpc_grpclb_destroy_serverlist(grpc_grpclb_serverlist *serverlist);
 int grpc_grpclb_duration_compare(const grpc_grpclb_duration *lhs,
                                  const grpc_grpclb_duration *rhs);
 
+gpr_timespec grpc_grpclb_duration_to_timespec(
+    grpc_grpclb_duration *duration_pb);
+
 /** Destroy \a initial_response */
 void grpc_grpclb_initial_response_destroy(
     grpc_grpclb_initial_response *response);
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 2b77cd39b8..b1c5dfc61c 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
@@ -189,7 +189,8 @@ static void pf_exit_idle_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol) {
 
 static int pf_pick_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol,
                           const grpc_lb_policy_pick_args *pick_args,
-                          grpc_connected_subchannel **target, void **user_data,
+                          grpc_connected_subchannel **target,
+                          grpc_call_context_element *context, void **user_data,
                           grpc_closure *on_complete) {
   pick_first_lb_policy *p = (pick_first_lb_policy *)pol;
   pending_pick *pp;
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 ff41e61b3e..4c17f9c082 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
@@ -414,7 +414,8 @@ static void rr_exit_idle_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol) {
 
 static int rr_pick_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol,
                           const grpc_lb_policy_pick_args *pick_args,
-                          grpc_connected_subchannel **target, void **user_data,
+                          grpc_connected_subchannel **target,
+                          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;
diff --git a/src/core/ext/filters/client_channel/subchannel.c b/src/core/ext/filters/client_channel/subchannel.c
index b2de85c4a1..1af3393a62 100644
--- a/src/core/ext/filters/client_channel/subchannel.c
+++ b/src/core/ext/filters/client_channel/subchannel.c
@@ -781,7 +781,7 @@ grpc_error *grpc_connected_subchannel_create_call(
   (*call)->connection = GRPC_CONNECTED_SUBCHANNEL_REF(con, "subchannel_call");
   const grpc_call_element_args call_args = {.call_stack = callstk,
                                             .server_transport_data = NULL,
-                                            .context = NULL,
+                                            .context = args->context,
                                             .path = args->path,
                                             .start_time = args->start_time,
                                             .deadline = args->deadline,
diff --git a/src/core/ext/filters/client_channel/subchannel.h b/src/core/ext/filters/client_channel/subchannel.h
index 6473de49b0..e433c33e40 100644
--- a/src/core/ext/filters/client_channel/subchannel.h
+++ b/src/core/ext/filters/client_channel/subchannel.h
@@ -119,6 +119,7 @@ typedef struct {
   gpr_timespec start_time;
   gpr_timespec deadline;
   gpr_arena *arena;
+  grpc_call_context_element *context;
 } grpc_connected_subchannel_call_args;
 
 grpc_error *grpc_connected_subchannel_create_call(
diff --git a/src/core/lib/channel/context.h b/src/core/lib/channel/context.h
index 6c931ad28a..f0a21113c5 100644
--- a/src/core/lib/channel/context.h
+++ b/src/core/lib/channel/context.h
@@ -50,6 +50,9 @@ typedef enum {
   /// Reserved for traffic_class_context.
   GRPC_CONTEXT_TRAFFIC,
 
+  /// Value is a \a grpc_grpclb_client_stats.
+  GRPC_GRPCLB_CLIENT_STATS,
+
   GRPC_CONTEXT_COUNT
 } grpc_context_index;
 
diff --git a/src/csharp/Grpc.IntegrationTesting/ClientRunners.cs b/src/csharp/Grpc.IntegrationTesting/ClientRunners.cs
index b9c0fe6d0d..c9f7c42b71 100644
--- a/src/csharp/Grpc.IntegrationTesting/ClientRunners.cs
+++ b/src/csharp/Grpc.IntegrationTesting/ClientRunners.cs
@@ -179,6 +179,9 @@ namespace Grpc.IntegrationTesting
                 statsResetCount.Increment();
             }
 
+            GrpcEnvironment.Logger.Info("[ClientRunnerImpl.GetStats] GC collection counts: gen0 {0}, gen1 {1}, gen2 {2}, gen3 {3} (histogram reset count:{4}, seconds since reset: {5})",
+                GC.CollectionCount(0), GC.CollectionCount(1), GC.CollectionCount(2), GC.CollectionCount(3), statsResetCount.Count, secondsElapsed);
+
             // TODO: populate user time and system time
             return new ClientStats
             {
diff --git a/src/csharp/Grpc.IntegrationTesting/QpsWorker.cs b/src/csharp/Grpc.IntegrationTesting/QpsWorker.cs
index b17b2c2183..486befe964 100644
--- a/src/csharp/Grpc.IntegrationTesting/QpsWorker.cs
+++ b/src/csharp/Grpc.IntegrationTesting/QpsWorker.cs
@@ -95,10 +95,13 @@ namespace Grpc.IntegrationTesting
                 Ports = { new ServerPort(host, options.DriverPort, ServerCredentials.Insecure )}
             };
             int boundPort = server.Ports.Single().BoundPort;
-            Console.WriteLine("Running qps worker server on " + string.Format("{0}:{1}", host, boundPort));
+            GrpcEnvironment.Logger.Info("Running qps worker server on {0}:{1}", host, boundPort);
             server.Start();
             await tcs.Task;
             await server.ShutdownAsync();
+
+            GrpcEnvironment.Logger.Info("GC collection counts (after shutdown): gen0 {0}, gen1 {1}, gen2 {2}, gen3 {3}",
+                GC.CollectionCount(0), GC.CollectionCount(1), GC.CollectionCount(2), GC.CollectionCount(3));
         }
     }
 }
diff --git a/src/csharp/Grpc.IntegrationTesting/ServerRunners.cs b/src/csharp/Grpc.IntegrationTesting/ServerRunners.cs
index 8689d188ae..7ab7734700 100644
--- a/src/csharp/Grpc.IntegrationTesting/ServerRunners.cs
+++ b/src/csharp/Grpc.IntegrationTesting/ServerRunners.cs
@@ -154,6 +154,9 @@ namespace Grpc.IntegrationTesting
         {
             var secondsElapsed = wallClockStopwatch.GetElapsedSnapshot(reset).TotalSeconds;
 
+            GrpcEnvironment.Logger.Info("[ServerRunner.GetStats] GC collection counts: gen0 {0}, gen1 {1}, gen2 {2}, gen3 {3} (seconds since last reset {4})",
+                GC.CollectionCount(0), GC.CollectionCount(1), GC.CollectionCount(2), GC.CollectionCount(3), secondsElapsed);
+
             // TODO: populate user time and system time
             return new ServerStats
             {
diff --git a/src/python/grpcio/grpc_core_dependencies.py b/src/python/grpcio/grpc_core_dependencies.py
index d2a570cc87..42c13b2cb6 100644
--- a/src/python/grpcio/grpc_core_dependencies.py
+++ b/src/python/grpcio/grpc_core_dependencies.py
@@ -280,8 +280,10 @@ CORE_SOURCE_FILES = [
   'src/core/ext/transport/chttp2/server/insecure/server_chttp2_posix.c',
   'src/core/ext/transport/chttp2/client/insecure/channel_create.c',
   'src/core/ext/transport/chttp2/client/insecure/channel_create_posix.c',
+  'src/core/ext/filters/client_channel/lb_policy/grpclb/client_load_reporting_filter.c',
   'src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.c',
   'src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel_secure.c',
+  'src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_client_stats.c',
   'src/core/ext/filters/client_channel/lb_policy/grpclb/load_balancer_api.c',
   'src/core/ext/filters/client_channel/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.c',
   'third_party/nanopb/pb_common.c',
diff --git a/test/cpp/end2end/BUILD b/test/cpp/end2end/BUILD
index 0bd41d153b..e867493fb9 100644
--- a/test/cpp/end2end/BUILD
+++ b/test/cpp/end2end/BUILD
@@ -198,6 +198,7 @@ cc_test(
     ],
 )
 
+
 cc_test(
     name = "grpclb_end2end_test",
     srcs = ["grpclb_end2end_test.cc"],
diff --git a/test/cpp/end2end/grpclb_end2end_test.cc b/test/cpp/end2end/grpclb_end2end_test.cc
index 8ebeba3522..30e1a1e0c9 100644
--- a/test/cpp/end2end/grpclb_end2end_test.cc
+++ b/test/cpp/end2end/grpclb_end2end_test.cc
@@ -147,12 +147,38 @@ grpc::string Ip4ToPackedString(const char* ip_str) {
   return grpc::string(reinterpret_cast<const char*>(&ip4), sizeof(ip4));
 }
 
+struct ClientStats {
+  size_t num_calls_started = 0;
+  size_t num_calls_finished = 0;
+  size_t num_calls_finished_with_drop_for_rate_limiting = 0;
+  size_t num_calls_finished_with_drop_for_load_balancing = 0;
+  size_t num_calls_finished_with_client_failed_to_send = 0;
+  size_t num_calls_finished_known_received = 0;
+
+  ClientStats& operator+=(const ClientStats& other) {
+    num_calls_started += other.num_calls_started;
+    num_calls_finished += other.num_calls_finished;
+    num_calls_finished_with_drop_for_rate_limiting +=
+        other.num_calls_finished_with_drop_for_rate_limiting;
+    num_calls_finished_with_drop_for_load_balancing +=
+        other.num_calls_finished_with_drop_for_load_balancing;
+    num_calls_finished_with_client_failed_to_send +=
+        other.num_calls_finished_with_client_failed_to_send;
+    num_calls_finished_known_received +=
+        other.num_calls_finished_known_received;
+    return *this;
+  }
+};
+
 class BalancerServiceImpl : public BalancerService {
  public:
   using Stream = ServerReaderWriter<LoadBalanceResponse, LoadBalanceRequest>;
   using ResponseDelayPair = std::pair<LoadBalanceResponse, int>;
 
-  BalancerServiceImpl() : shutdown_(false) {}
+  explicit BalancerServiceImpl(int client_load_reporting_interval_seconds)
+      : client_load_reporting_interval_seconds_(
+            client_load_reporting_interval_seconds),
+        shutdown_(false) {}
 
   Status BalanceLoad(ServerContext* context, Stream* stream) override {
     LoadBalanceRequest request;
@@ -160,16 +186,49 @@ class BalancerServiceImpl : public BalancerService {
     IncreaseRequestCount();
     gpr_log(GPR_INFO, "LB: recv msg '%s'", request.DebugString().c_str());
 
+    if (client_load_reporting_interval_seconds_ > 0) {
+      LoadBalanceResponse initial_response;
+      initial_response.mutable_initial_response()
+          ->mutable_client_stats_report_interval()
+          ->set_seconds(client_load_reporting_interval_seconds_);
+      stream->Write(initial_response);
+    }
+
     std::vector<ResponseDelayPair> responses_and_delays;
     {
       std::unique_lock<std::mutex> lock(mu_);
       responses_and_delays = responses_and_delays_;
     }
-
     for (const auto& response_and_delay : responses_and_delays) {
       if (shutdown_) break;
       SendResponse(stream, response_and_delay.first, response_and_delay.second);
     }
+
+    if (client_load_reporting_interval_seconds_ > 0) {
+      request.Clear();
+      stream->Read(&request);
+      gpr_log(GPR_INFO, "LB: recv client load report msg: '%s'",
+              request.DebugString().c_str());
+      GPR_ASSERT(request.has_client_stats());
+      client_stats_.num_calls_started +=
+          request.client_stats().num_calls_started();
+      client_stats_.num_calls_finished +=
+          request.client_stats().num_calls_finished();
+      client_stats_.num_calls_finished_with_drop_for_rate_limiting +=
+          request.client_stats()
+              .num_calls_finished_with_drop_for_rate_limiting();
+      client_stats_.num_calls_finished_with_drop_for_load_balancing +=
+          request.client_stats()
+              .num_calls_finished_with_drop_for_load_balancing();
+      client_stats_.num_calls_finished_with_client_failed_to_send +=
+          request.client_stats()
+              .num_calls_finished_with_client_failed_to_send();
+      client_stats_.num_calls_finished_known_received +=
+          request.client_stats().num_calls_finished_known_received();
+      std::lock_guard<std::mutex> lock(mu_);
+      cond_.notify_one();
+    }
+
     return Status::OK;
   }
 
@@ -194,6 +253,12 @@ class BalancerServiceImpl : public BalancerService {
     return response;
   }
 
+  const ClientStats& WaitForLoadReport() {
+    std::unique_lock<std::mutex> lock(mu_);
+    cond_.wait(lock);
+    return client_stats_;
+  }
+
  private:
   void SendResponse(Stream* stream, const LoadBalanceResponse& response,
                     int delay_ms) {
@@ -206,16 +271,23 @@ class BalancerServiceImpl : public BalancerService {
     IncreaseResponseCount();
   }
 
+  const int client_load_reporting_interval_seconds_;
   std::vector<ResponseDelayPair> responses_and_delays_;
+  std::mutex mu_;
+  std::condition_variable cond_;
+  ClientStats client_stats_;
   bool shutdown_;
 };
 
 class GrpclbEnd2endTest : public ::testing::Test {
  protected:
-  GrpclbEnd2endTest(int num_backends, int num_balancers)
+  GrpclbEnd2endTest(int num_backends, int num_balancers,
+                    int client_load_reporting_interval_seconds)
       : server_host_("localhost"),
         num_backends_(num_backends),
-        num_balancers_(num_balancers) {}
+        num_balancers_(num_balancers),
+        client_load_reporting_interval_seconds_(
+            client_load_reporting_interval_seconds) {}
 
   void SetUp() override {
     response_generator_ = grpc_fake_resolver_response_generator_create();
@@ -227,7 +299,8 @@ class GrpclbEnd2endTest : public ::testing::Test {
     }
     // Start the load balancers.
     for (size_t i = 0; i < num_balancers_; ++i) {
-      balancers_.emplace_back(new BalancerServiceImpl());
+      balancers_.emplace_back(
+          new BalancerServiceImpl(client_load_reporting_interval_seconds_));
       balancer_servers_.emplace_back(ServerThread<BalancerService>(
           "balancer", server_host_, balancers_.back().get()));
     }
@@ -261,6 +334,14 @@ class GrpclbEnd2endTest : public ::testing::Test {
     stub_ = grpc::testing::EchoTestService::NewStub(channel_);
   }
 
+  ClientStats WaitForLoadReports() {
+    ClientStats client_stats;
+    for (const auto& balancer : balancers_) {
+      client_stats += balancer->WaitForLoadReport();
+    }
+    return client_stats;
+  }
+
   struct AddressData {
     int port;
     bool is_balancer;
@@ -367,6 +448,7 @@ class GrpclbEnd2endTest : public ::testing::Test {
   const grpc::string server_host_;
   const size_t num_backends_;
   const size_t num_balancers_;
+  const int client_load_reporting_interval_seconds_;
   std::shared_ptr<Channel> channel_;
   std::unique_ptr<grpc::testing::EchoTestService::Stub> stub_;
 
@@ -381,7 +463,7 @@ class GrpclbEnd2endTest : public ::testing::Test {
 
 class SingleBalancerTest : public GrpclbEnd2endTest {
  public:
-  SingleBalancerTest() : GrpclbEnd2endTest(4, 1) {}
+  SingleBalancerTest() : GrpclbEnd2endTest(4, 1, 0) {}
 };
 
 TEST_F(SingleBalancerTest, Vanilla) {
@@ -505,6 +587,41 @@ TEST_F(SingleBalancerTest, RepeatedServerlist) {
   EXPECT_EQ("grpclb", channel_->GetLoadBalancingPolicyName());
 }
 
+class SingleBalancerWithClientLoadReportingTest : public GrpclbEnd2endTest {
+ public:
+  SingleBalancerWithClientLoadReportingTest() : GrpclbEnd2endTest(4, 1, 2) {}
+};
+
+TEST_F(SingleBalancerWithClientLoadReportingTest, Vanilla) {
+  ScheduleResponseForBalancer(
+      0, BalancerServiceImpl::BuildResponseForBackends(GetBackendPorts()), 0);
+  // Start servers and send 100 RPCs per server.
+  const auto& statuses_and_responses = SendRpc(kMessage_, 100 * num_backends_);
+
+  for (const auto& status_and_response : statuses_and_responses) {
+    EXPECT_TRUE(status_and_response.first.ok());
+    EXPECT_EQ(status_and_response.second.message(), kMessage_);
+  }
+
+  // Each backend should have gotten 100 requests.
+  for (size_t i = 0; i < backends_.size(); ++i) {
+    EXPECT_EQ(100, backend_servers_[i].service_->request_count());
+  }
+  // The balancer got a single request.
+  EXPECT_EQ(1, balancer_servers_[0].service_->request_count());
+  // and sent a single response.
+  EXPECT_EQ(1, balancer_servers_[0].service_->response_count());
+
+  const ClientStats client_stats = WaitForLoadReports();
+  EXPECT_EQ(100 * num_backends_, client_stats.num_calls_started);
+  EXPECT_EQ(100 * num_backends_, client_stats.num_calls_finished);
+  EXPECT_EQ(0U, client_stats.num_calls_finished_with_drop_for_rate_limiting);
+  EXPECT_EQ(0U, client_stats.num_calls_finished_with_drop_for_load_balancing);
+  EXPECT_EQ(0U, client_stats.num_calls_finished_with_client_failed_to_send);
+  EXPECT_EQ(100 * num_backends_,
+            client_stats.num_calls_finished_known_received);
+}
+
 }  // namespace
 }  // namespace testing
 }  // namespace grpc
diff --git a/tools/doxygen/Doxyfile.core.internal b/tools/doxygen/Doxyfile.core.internal
index f49c2de76c..51d77c2b52 100644
--- a/tools/doxygen/Doxyfile.core.internal
+++ b/tools/doxygen/Doxyfile.core.internal
@@ -910,10 +910,14 @@ src/core/ext/filters/client_channel/http_proxy.c \
 src/core/ext/filters/client_channel/http_proxy.h \
 src/core/ext/filters/client_channel/lb_policy.c \
 src/core/ext/filters/client_channel/lb_policy.h \
+src/core/ext/filters/client_channel/lb_policy/grpclb/client_load_reporting_filter.c \
+src/core/ext/filters/client_channel/lb_policy/grpclb/client_load_reporting_filter.h \
 src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.c \
 src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.h \
 src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel.h \
 src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel_secure.c \
+src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_client_stats.c \
+src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_client_stats.h \
 src/core/ext/filters/client_channel/lb_policy/grpclb/load_balancer_api.c \
 src/core/ext/filters/client_channel/lb_policy/grpclb/load_balancer_api.h \
 src/core/ext/filters/client_channel/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.c \
diff --git a/tools/internal_ci/linux/grpc_master.sh b/tools/internal_ci/linux/grpc_master.sh
index 9ecf123959..ec4bb2bda1 100755
--- a/tools/internal_ci/linux/grpc_master.sh
+++ b/tools/internal_ci/linux/grpc_master.sh
@@ -47,12 +47,4 @@ git submodule update --init
 
 # download docker images from dockerhub
 export DOCKERHUB_ORGANIZATION=grpctesting
-tools/run_tests/run_tests.py -l c -t -x sponge_log.xml || FAILED="true"
-
-# kill port_server.py to prevent the build from hanging
-ps aux | grep port_server\\.py | awk '{print $2}' | xargs kill -9
-
-if [ "$FAILED" != "" ]
-then
-  exit 1
-fi
+tools/run_tests/run_tests_matrix.py -f basictests linux --internal_ci
diff --git a/tools/internal_ci/macos/grpc_master.cfg b/tools/internal_ci/macos/grpc_master.cfg
new file mode 100644
index 0000000000..039c99ec42
--- /dev/null
+++ b/tools/internal_ci/macos/grpc_master.cfg
@@ -0,0 +1,39 @@
+# Copyright 2017, 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.
+
+# Config file for the internal CI (in protobuf text format)
+
+# Location of the continuous shell script in repository.
+build_file: "grpc/tools/internal_ci/macos/grpc_master.sh"
+timeout_mins: 240
+action {
+  define_artifacts {
+    regex: "**/*sponge_log.xml"
+  }
+}
diff --git a/tools/internal_ci/macos/grpc_master.sh b/tools/internal_ci/macos/grpc_master.sh
new file mode 100755
index 0000000000..4ce1af73a5
--- /dev/null
+++ b/tools/internal_ci/macos/grpc_master.sh
@@ -0,0 +1,46 @@
+#!/bin/bash
+# Copyright 2017, 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.
+
+set -ex
+
+# change to grpc repo root
+cd $(dirname $0)/../../..
+
+git submodule update --init
+
+tools/run_tests/run_tests_matrix.py -f basictests macos --internal_ci || FAILED="true"
+
+# kill port_server.py to prevent the build from hanging
+ps aux | grep port_server\\.py | awk '{print $2}' | xargs kill -9
+
+if [ "$FAILED" != "" ]
+then
+  exit 1
+fi
diff --git a/tools/internal_ci/windows/grpc_master.bat b/tools/internal_ci/windows/grpc_master.bat
index 8943390a8d..b6f3c8790f 100644
--- a/tools/internal_ci/windows/grpc_master.bat
+++ b/tools/internal_ci/windows/grpc_master.bat
@@ -36,7 +36,7 @@ cd /d %~dp0\..\..\..
 
 git submodule update --init
 
-python tools/run_tests/run_tests_matrix.py -f basictests windows -j 1 --inner_jobs 8 || goto :error
+python tools/run_tests/run_tests_matrix.py -f basictests windows -j 1 --inner_jobs 8 --internal_ci || goto :error
 goto :EOF
 
 :error
diff --git a/tools/internal_ci/windows/grpc_portability_master.bat b/tools/internal_ci/windows/grpc_portability_master.bat
index b98c70146c..789808664b 100644
--- a/tools/internal_ci/windows/grpc_portability_master.bat
+++ b/tools/internal_ci/windows/grpc_portability_master.bat
@@ -36,7 +36,7 @@ cd /d %~dp0\..\..\..
 
 git submodule update --init
 
-python tools/run_tests/run_tests_matrix.py -f portability windows -j 1 --inner_jobs 8 || goto :error
+python tools/run_tests/run_tests_matrix.py -f portability windows -j 1 --inner_jobs 8 --internal_ci || goto :error
 goto :EOF
 
 :error
diff --git a/tools/run_tests/generated/sources_and_headers.json b/tools/run_tests/generated/sources_and_headers.json
index adaf5481b2..c962823437 100644
--- a/tools/run_tests/generated/sources_and_headers.json
+++ b/tools/run_tests/generated/sources_and_headers.json
@@ -8234,8 +8234,10 @@
       "nanopb"
     ], 
     "headers": [
+      "src/core/ext/filters/client_channel/lb_policy/grpclb/client_load_reporting_filter.h", 
       "src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.h", 
       "src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel.h", 
+      "src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_client_stats.h", 
       "src/core/ext/filters/client_channel/lb_policy/grpclb/load_balancer_api.h", 
       "src/core/ext/filters/client_channel/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.h"
     ], 
@@ -8243,10 +8245,14 @@
     "language": "c", 
     "name": "grpc_lb_policy_grpclb", 
     "src": [
+      "src/core/ext/filters/client_channel/lb_policy/grpclb/client_load_reporting_filter.c", 
+      "src/core/ext/filters/client_channel/lb_policy/grpclb/client_load_reporting_filter.h", 
       "src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.c", 
       "src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.h", 
       "src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel.c", 
       "src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel.h", 
+      "src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_client_stats.c", 
+      "src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_client_stats.h", 
       "src/core/ext/filters/client_channel/lb_policy/grpclb/load_balancer_api.c", 
       "src/core/ext/filters/client_channel/lb_policy/grpclb/load_balancer_api.h", 
       "src/core/ext/filters/client_channel/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.c", 
@@ -8264,8 +8270,10 @@
       "nanopb"
     ], 
     "headers": [
+      "src/core/ext/filters/client_channel/lb_policy/grpclb/client_load_reporting_filter.h", 
       "src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.h", 
       "src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel.h", 
+      "src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_client_stats.h", 
       "src/core/ext/filters/client_channel/lb_policy/grpclb/load_balancer_api.h", 
       "src/core/ext/filters/client_channel/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.h"
     ], 
@@ -8273,10 +8281,14 @@
     "language": "c", 
     "name": "grpc_lb_policy_grpclb_secure", 
     "src": [
+      "src/core/ext/filters/client_channel/lb_policy/grpclb/client_load_reporting_filter.c", 
+      "src/core/ext/filters/client_channel/lb_policy/grpclb/client_load_reporting_filter.h", 
       "src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.c", 
       "src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.h", 
       "src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel.h", 
       "src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_channel_secure.c", 
+      "src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_client_stats.c", 
+      "src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb_client_stats.h", 
       "src/core/ext/filters/client_channel/lb_policy/grpclb/load_balancer_api.c", 
       "src/core/ext/filters/client_channel/lb_policy/grpclb/load_balancer_api.h", 
       "src/core/ext/filters/client_channel/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.c", 
diff --git a/tools/run_tests/helper_scripts/pre_build_cmake.bat b/tools/run_tests/helper_scripts/pre_build_cmake.bat
index c937b9e09f..c721e1624d 100644
--- a/tools/run_tests/helper_scripts/pre_build_cmake.bat
+++ b/tools/run_tests/helper_scripts/pre_build_cmake.bat
@@ -37,7 +37,10 @@ mkdir build
 cd build
 
 @rem TODO(jtattermusch): Stop hardcoding path to yasm once Jenkins workers can locate yasm correctly
-cmake -G "Visual Studio 14 2015" -DgRPC_BUILD_TESTS=ON -DCMAKE_ASM_NASM_COMPILER="C:/Program Files (x86)/yasm/yasm.exe" ../.. || goto :error
+@rem If yasm is not on the path, use hardcoded path instead.
+yasm --version || set USE_HARDCODED_YASM_PATH_MAYBE=-DCMAKE_ASM_NASM_COMPILER="C:/Program Files (x86)/yasm/yasm.exe"
+
+cmake -G "Visual Studio 14 2015" -DgRPC_BUILD_TESTS=ON %USE_HARDCODED_YASM_PATH_MAYBE% ../.. || goto :error
 
 endlocal
 
diff --git a/tools/run_tests/helper_scripts/pre_build_csharp.bat b/tools/run_tests/helper_scripts/pre_build_csharp.bat
index e59dac4edc..47ebd8bee3 100644
--- a/tools/run_tests/helper_scripts/pre_build_csharp.bat
+++ b/tools/run_tests/helper_scripts/pre_build_csharp.bat
@@ -42,8 +42,12 @@ mkdir build
 cd build
 mkdir %ARCHITECTURE%
 cd %ARCHITECTURE%
+
 @rem TODO(jtattermusch): Stop hardcoding path to yasm once Jenkins workers can locate yasm correctly
-cmake -G "Visual Studio 14 2015" -A %ARCHITECTURE% -DgRPC_BUILD_TESTS=OFF -DgRPC_MSVC_STATIC_RUNTIME=ON -DCMAKE_ASM_NASM_COMPILER="C:/Program Files (x86)/yasm/yasm.exe" ../../.. || goto :error
+@rem If yasm is not on the path, use hardcoded path instead.
+yasm --version || set USE_HARDCODED_YASM_PATH_MAYBE=-DCMAKE_ASM_NASM_COMPILER="C:/Program Files (x86)/yasm/yasm.exe"
+
+cmake -G "Visual Studio 14 2015" -A %ARCHITECTURE% -DgRPC_BUILD_TESTS=OFF -DgRPC_MSVC_STATIC_RUNTIME=ON %USE_HARDCODED_YASM_PATH_MAYBE% ../../.. || goto :error
 
 cd ..\..\..\src\csharp
 
diff --git a/tools/run_tests/performance/scenario_config.py b/tools/run_tests/performance/scenario_config.py
index ce0808829f..08411bf9a4 100644
--- a/tools/run_tests/performance/scenario_config.py
+++ b/tools/run_tests/performance/scenario_config.py
@@ -410,6 +410,21 @@ class CSharpLanguage:
         categories=[SMOKETEST, SCALABLE])
 
     yield _ping_pong_scenario(
+        'csharp_generic_async_streaming_ping_pong_insecure_1MB', rpc_type='STREAMING',
+        client_type='ASYNC_CLIENT', server_type='ASYNC_GENERIC_SERVER',
+        req_size=1024*1024, resp_size=1024*1024,
+        use_generic_payload=True,
+        secure=False,
+        categories=[SMOKETEST, SCALABLE])
+
+    yield _ping_pong_scenario(
+        'csharp_generic_async_streaming_qps_unconstrained_insecure', rpc_type='STREAMING',
+        client_type='ASYNC_CLIENT', server_type='ASYNC_GENERIC_SERVER',
+        unconstrained_client='async', use_generic_payload=True,
+        secure=False,
+        categories=[SMOKETEST, SCALABLE])
+
+    yield _ping_pong_scenario(
         'csharp_protobuf_async_streaming_ping_pong', rpc_type='STREAMING',
         client_type='ASYNC_CLIENT', server_type='ASYNC_SERVER')
 
@@ -469,7 +484,6 @@ class CSharpLanguage:
         req_size=1024*1024, resp_size=1024*1024,
         categories=[SMOKETEST, SCALABLE])
 
-
   def __str__(self):
     return 'csharp'
 
diff --git a/vsprojects/vcxproj/grpc/grpc.vcxproj b/vsprojects/vcxproj/grpc/grpc.vcxproj
index 71520098a6..86b5856d68 100644
--- a/vsprojects/vcxproj/grpc/grpc.vcxproj
+++ b/vsprojects/vcxproj/grpc/grpc.vcxproj
@@ -475,8 +475,10 @@
     <ClInclude Include="$(SolutionDir)\..\src\core\ext\filters\client_channel\uri_parser.h" />
     <ClInclude Include="$(SolutionDir)\..\src\core\ext\filters\deadline\deadline_filter.h" />
     <ClInclude Include="$(SolutionDir)\..\src\core\ext\transport\chttp2\client\chttp2_connector.h" />
+    <ClInclude Include="$(SolutionDir)\..\src\core\ext\filters\client_channel\lb_policy\grpclb\client_load_reporting_filter.h" />
     <ClInclude Include="$(SolutionDir)\..\src\core\ext\filters\client_channel\lb_policy\grpclb\grpclb.h" />
     <ClInclude Include="$(SolutionDir)\..\src\core\ext\filters\client_channel\lb_policy\grpclb\grpclb_channel.h" />
+    <ClInclude Include="$(SolutionDir)\..\src\core\ext\filters\client_channel\lb_policy\grpclb\grpclb_client_stats.h" />
     <ClInclude Include="$(SolutionDir)\..\src\core\ext\filters\client_channel\lb_policy\grpclb\load_balancer_api.h" />
     <ClInclude Include="$(SolutionDir)\..\src\core\ext\filters\client_channel\lb_policy\grpclb\proto\grpc\lb\v1\load_balancer.pb.h" />
     <ClInclude Include="$(SolutionDir)\..\third_party\nanopb\pb.h" />
@@ -915,10 +917,14 @@
     </ClCompile>
     <ClCompile Include="$(SolutionDir)\..\src\core\ext\transport\chttp2\client\insecure\channel_create_posix.c">
     </ClCompile>
+    <ClCompile Include="$(SolutionDir)\..\src\core\ext\filters\client_channel\lb_policy\grpclb\client_load_reporting_filter.c">
+    </ClCompile>
     <ClCompile Include="$(SolutionDir)\..\src\core\ext\filters\client_channel\lb_policy\grpclb\grpclb.c">
     </ClCompile>
     <ClCompile Include="$(SolutionDir)\..\src\core\ext\filters\client_channel\lb_policy\grpclb\grpclb_channel_secure.c">
     </ClCompile>
+    <ClCompile Include="$(SolutionDir)\..\src\core\ext\filters\client_channel\lb_policy\grpclb\grpclb_client_stats.c">
+    </ClCompile>
     <ClCompile Include="$(SolutionDir)\..\src\core\ext\filters\client_channel\lb_policy\grpclb\load_balancer_api.c">
     </ClCompile>
     <ClCompile Include="$(SolutionDir)\..\src\core\ext\filters\client_channel\lb_policy\grpclb\proto\grpc\lb\v1\load_balancer.pb.c">
diff --git a/vsprojects/vcxproj/grpc/grpc.vcxproj.filters b/vsprojects/vcxproj/grpc/grpc.vcxproj.filters
index de2dfe67e6..943ad521f7 100644
--- a/vsprojects/vcxproj/grpc/grpc.vcxproj.filters
+++ b/vsprojects/vcxproj/grpc/grpc.vcxproj.filters
@@ -613,12 +613,18 @@
     <ClCompile Include="$(SolutionDir)\..\src\core\ext\transport\chttp2\client\insecure\channel_create_posix.c">
       <Filter>src\core\ext\transport\chttp2\client\insecure</Filter>
     </ClCompile>
+    <ClCompile Include="$(SolutionDir)\..\src\core\ext\filters\client_channel\lb_policy\grpclb\client_load_reporting_filter.c">
+      <Filter>src\core\ext\filters\client_channel\lb_policy\grpclb</Filter>
+    </ClCompile>
     <ClCompile Include="$(SolutionDir)\..\src\core\ext\filters\client_channel\lb_policy\grpclb\grpclb.c">
       <Filter>src\core\ext\filters\client_channel\lb_policy\grpclb</Filter>
     </ClCompile>
     <ClCompile Include="$(SolutionDir)\..\src\core\ext\filters\client_channel\lb_policy\grpclb\grpclb_channel_secure.c">
       <Filter>src\core\ext\filters\client_channel\lb_policy\grpclb</Filter>
     </ClCompile>
+    <ClCompile Include="$(SolutionDir)\..\src\core\ext\filters\client_channel\lb_policy\grpclb\grpclb_client_stats.c">
+      <Filter>src\core\ext\filters\client_channel\lb_policy\grpclb</Filter>
+    </ClCompile>
     <ClCompile Include="$(SolutionDir)\..\src\core\ext\filters\client_channel\lb_policy\grpclb\load_balancer_api.c">
       <Filter>src\core\ext\filters\client_channel\lb_policy\grpclb</Filter>
     </ClCompile>
@@ -1334,12 +1340,18 @@
     <ClInclude Include="$(SolutionDir)\..\src\core\ext\transport\chttp2\client\chttp2_connector.h">
       <Filter>src\core\ext\transport\chttp2\client</Filter>
     </ClInclude>
+    <ClInclude Include="$(SolutionDir)\..\src\core\ext\filters\client_channel\lb_policy\grpclb\client_load_reporting_filter.h">
+      <Filter>src\core\ext\filters\client_channel\lb_policy\grpclb</Filter>
+    </ClInclude>
     <ClInclude Include="$(SolutionDir)\..\src\core\ext\filters\client_channel\lb_policy\grpclb\grpclb.h">
       <Filter>src\core\ext\filters\client_channel\lb_policy\grpclb</Filter>
     </ClInclude>
     <ClInclude Include="$(SolutionDir)\..\src\core\ext\filters\client_channel\lb_policy\grpclb\grpclb_channel.h">
       <Filter>src\core\ext\filters\client_channel\lb_policy\grpclb</Filter>
     </ClInclude>
+    <ClInclude Include="$(SolutionDir)\..\src\core\ext\filters\client_channel\lb_policy\grpclb\grpclb_client_stats.h">
+      <Filter>src\core\ext\filters\client_channel\lb_policy\grpclb</Filter>
+    </ClInclude>
     <ClInclude Include="$(SolutionDir)\..\src\core\ext\filters\client_channel\lb_policy\grpclb\load_balancer_api.h">
       <Filter>src\core\ext\filters\client_channel\lb_policy\grpclb</Filter>
     </ClInclude>
diff --git a/vsprojects/vcxproj/grpc_unsecure/grpc_unsecure.vcxproj b/vsprojects/vcxproj/grpc_unsecure/grpc_unsecure.vcxproj
index 0bfda72e81..2db0ffa692 100644
--- a/vsprojects/vcxproj/grpc_unsecure/grpc_unsecure.vcxproj
+++ b/vsprojects/vcxproj/grpc_unsecure/grpc_unsecure.vcxproj
@@ -444,8 +444,10 @@
     <ClInclude Include="$(SolutionDir)\..\src\core\ext\filters\client_channel\resolver\dns\c_ares\grpc_ares_wrapper.h" />
     <ClInclude Include="$(SolutionDir)\..\src\core\ext\filters\load_reporting\load_reporting.h" />
     <ClInclude Include="$(SolutionDir)\..\src\core\ext\filters\load_reporting\load_reporting_filter.h" />
+    <ClInclude Include="$(SolutionDir)\..\src\core\ext\filters\client_channel\lb_policy\grpclb\client_load_reporting_filter.h" />
     <ClInclude Include="$(SolutionDir)\..\src\core\ext\filters\client_channel\lb_policy\grpclb\grpclb.h" />
     <ClInclude Include="$(SolutionDir)\..\src\core\ext\filters\client_channel\lb_policy\grpclb\grpclb_channel.h" />
+    <ClInclude Include="$(SolutionDir)\..\src\core\ext\filters\client_channel\lb_policy\grpclb\grpclb_client_stats.h" />
     <ClInclude Include="$(SolutionDir)\..\src\core\ext\filters\client_channel\lb_policy\grpclb\load_balancer_api.h" />
     <ClInclude Include="$(SolutionDir)\..\src\core\ext\filters\client_channel\lb_policy\grpclb\proto\grpc\lb\v1\load_balancer.pb.h" />
     <ClInclude Include="$(SolutionDir)\..\third_party\nanopb\pb.h" />
@@ -836,10 +838,14 @@
     </ClCompile>
     <ClCompile Include="$(SolutionDir)\..\src\core\ext\filters\load_reporting\load_reporting_filter.c">
     </ClCompile>
+    <ClCompile Include="$(SolutionDir)\..\src\core\ext\filters\client_channel\lb_policy\grpclb\client_load_reporting_filter.c">
+    </ClCompile>
     <ClCompile Include="$(SolutionDir)\..\src\core\ext\filters\client_channel\lb_policy\grpclb\grpclb.c">
     </ClCompile>
     <ClCompile Include="$(SolutionDir)\..\src\core\ext\filters\client_channel\lb_policy\grpclb\grpclb_channel.c">
     </ClCompile>
+    <ClCompile Include="$(SolutionDir)\..\src\core\ext\filters\client_channel\lb_policy\grpclb\grpclb_client_stats.c">
+    </ClCompile>
     <ClCompile Include="$(SolutionDir)\..\src\core\ext\filters\client_channel\lb_policy\grpclb\load_balancer_api.c">
     </ClCompile>
     <ClCompile Include="$(SolutionDir)\..\src\core\ext\filters\client_channel\lb_policy\grpclb\proto\grpc\lb\v1\load_balancer.pb.c">
diff --git a/vsprojects/vcxproj/grpc_unsecure/grpc_unsecure.vcxproj.filters b/vsprojects/vcxproj/grpc_unsecure/grpc_unsecure.vcxproj.filters
index 63c8d7f254..c7d6670db1 100644
--- a/vsprojects/vcxproj/grpc_unsecure/grpc_unsecure.vcxproj.filters
+++ b/vsprojects/vcxproj/grpc_unsecure/grpc_unsecure.vcxproj.filters
@@ -547,12 +547,18 @@
     <ClCompile Include="$(SolutionDir)\..\src\core\ext\filters\load_reporting\load_reporting_filter.c">
       <Filter>src\core\ext\filters\load_reporting</Filter>
     </ClCompile>
+    <ClCompile Include="$(SolutionDir)\..\src\core\ext\filters\client_channel\lb_policy\grpclb\client_load_reporting_filter.c">
+      <Filter>src\core\ext\filters\client_channel\lb_policy\grpclb</Filter>
+    </ClCompile>
     <ClCompile Include="$(SolutionDir)\..\src\core\ext\filters\client_channel\lb_policy\grpclb\grpclb.c">
       <Filter>src\core\ext\filters\client_channel\lb_policy\grpclb</Filter>
     </ClCompile>
     <ClCompile Include="$(SolutionDir)\..\src\core\ext\filters\client_channel\lb_policy\grpclb\grpclb_channel.c">
       <Filter>src\core\ext\filters\client_channel\lb_policy\grpclb</Filter>
     </ClCompile>
+    <ClCompile Include="$(SolutionDir)\..\src\core\ext\filters\client_channel\lb_policy\grpclb\grpclb_client_stats.c">
+      <Filter>src\core\ext\filters\client_channel\lb_policy\grpclb</Filter>
+    </ClCompile>
     <ClCompile Include="$(SolutionDir)\..\src\core\ext\filters\client_channel\lb_policy\grpclb\load_balancer_api.c">
       <Filter>src\core\ext\filters\client_channel\lb_policy\grpclb</Filter>
     </ClCompile>
@@ -1181,12 +1187,18 @@
     <ClInclude Include="$(SolutionDir)\..\src\core\ext\filters\load_reporting\load_reporting_filter.h">
       <Filter>src\core\ext\filters\load_reporting</Filter>
     </ClInclude>
+    <ClInclude Include="$(SolutionDir)\..\src\core\ext\filters\client_channel\lb_policy\grpclb\client_load_reporting_filter.h">
+      <Filter>src\core\ext\filters\client_channel\lb_policy\grpclb</Filter>
+    </ClInclude>
     <ClInclude Include="$(SolutionDir)\..\src\core\ext\filters\client_channel\lb_policy\grpclb\grpclb.h">
       <Filter>src\core\ext\filters\client_channel\lb_policy\grpclb</Filter>
     </ClInclude>
     <ClInclude Include="$(SolutionDir)\..\src\core\ext\filters\client_channel\lb_policy\grpclb\grpclb_channel.h">
       <Filter>src\core\ext\filters\client_channel\lb_policy\grpclb</Filter>
     </ClInclude>
+    <ClInclude Include="$(SolutionDir)\..\src\core\ext\filters\client_channel\lb_policy\grpclb\grpclb_client_stats.h">
+      <Filter>src\core\ext\filters\client_channel\lb_policy\grpclb</Filter>
+    </ClInclude>
     <ClInclude Include="$(SolutionDir)\..\src\core\ext\filters\client_channel\lb_policy\grpclb\load_balancer_api.h">
       <Filter>src\core\ext\filters\client_channel\lb_policy\grpclb</Filter>
     </ClInclude>