Merge pull request #5901 from dgquintas/lr_hook

Load Reporting hook

22 files changed, 509 insertions, 79 deletions

diff --git a/src/core/ext/census/grpc_filter.c b/src/core/ext/census/grpc_filter.c
index 5e278ef127..8c4c17ad9a 100644
--- a/src/core/ext/census/grpc_filter.c
+++ b/src/core/ext/census/grpc_filter.c
@@ -134,7 +134,9 @@ static void client_init_call_elem(grpc_exec_ctx *exec_ctx,
 }
 
 static void client_destroy_call_elem(grpc_exec_ctx *exec_ctx,
-                                     grpc_call_element *elem, void *ignored) {
+                                     grpc_call_element *elem,
+                                     const grpc_call_stats *stats,
+                                     void *ignored) {
   call_data *d = elem->call_data;
   GPR_ASSERT(d != NULL);
   /* TODO(hongyu): record rpc client stats and census_rpc_end_op here */
@@ -152,7 +154,9 @@ static void server_init_call_elem(grpc_exec_ctx *exec_ctx,
 }
 
 static void server_destroy_call_elem(grpc_exec_ctx *exec_ctx,
-                                     grpc_call_element *elem, void *ignored) {
+                                     grpc_call_element *elem,
+                                     const grpc_call_stats *stats,
+                                     void *ignored) {
   call_data *d = elem->call_data;
   GPR_ASSERT(d != NULL);
   /* TODO(hongyu): record rpc server stats and census_tracing_end_op here */
diff --git a/src/core/ext/client_config/client_channel.c b/src/core/ext/client_config/client_channel.c
index 9b5a078aec..642ae9ce59 100644
--- a/src/core/ext/client_config/client_channel.c
+++ b/src/core/ext/client_config/client_channel.c
@@ -416,6 +416,7 @@ static void init_call_elem(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
 
 /* Destructor for call_data */
 static void destroy_call_elem(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
+                              const grpc_call_stats *stats,
                               void *and_free_memory) {
   grpc_subchannel_call_holder_destroy(exec_ctx, elem->call_data);
   gpr_free(and_free_memory);
diff --git a/src/core/ext/client_config/subchannel.c b/src/core/ext/client_config/subchannel.c
index cfd39e7cfb..f7d98ec4d9 100644
--- a/src/core/ext/client_config/subchannel.c
+++ b/src/core/ext/client_config/subchannel.c
@@ -645,7 +645,7 @@ static void subchannel_call_destroy(grpc_exec_ctx *exec_ctx, void *call,
   grpc_subchannel_call *c = call;
   GPR_TIMER_BEGIN("grpc_subchannel_call_unref.destroy", 0);
   grpc_connected_subchannel *connection = c->connection;
-  grpc_call_stack_destroy(exec_ctx, SUBCHANNEL_CALL_TO_CALL_STACK(c), c);
+  grpc_call_stack_destroy(exec_ctx, SUBCHANNEL_CALL_TO_CALL_STACK(c), NULL, c);
   GRPC_CONNECTED_SUBCHANNEL_UNREF(exec_ctx, connection, "subchannel_call");
   GPR_TIMER_END("grpc_subchannel_call_unref.destroy", 0);
 }
diff --git a/src/core/ext/load_reporting/load_reporting.c b/src/core/ext/load_reporting/load_reporting.c
new file mode 100644
index 0000000000..60082dbaaa
--- /dev/null
+++ b/src/core/ext/load_reporting/load_reporting.c
@@ -0,0 +1,132 @@
+/*
+ *
+ * Copyright 2016, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#include <limits.h>
+#include <string.h>
+
+#include <grpc/support/alloc.h>
+#include <grpc/support/sync.h>
+
+#include "src/core/ext/load_reporting/load_reporting.h"
+#include "src/core/ext/load_reporting/load_reporting_filter.h"
+#include "src/core/lib/channel/channel_stack_builder.h"
+#include "src/core/lib/surface/channel_init.h"
+
+struct grpc_load_reporting_config {
+  grpc_load_reporting_fn fn;
+  void *user_data;
+};
+
+grpc_load_reporting_config *grpc_load_reporting_config_create(
+    grpc_load_reporting_fn fn, void *user_data) {
+  GPR_ASSERT(fn != NULL);
+  grpc_load_reporting_config *lrc =
+      gpr_malloc(sizeof(grpc_load_reporting_config));
+  lrc->fn = fn;
+  lrc->user_data = user_data;
+  return lrc;
+}
+
+grpc_load_reporting_config *grpc_load_reporting_config_copy(
+    grpc_load_reporting_config *src) {
+  return grpc_load_reporting_config_create(src->fn, src->user_data);
+}
+
+void grpc_load_reporting_config_destroy(grpc_load_reporting_config *lrc) {
+  gpr_free(lrc);
+}
+
+void grpc_load_reporting_config_call(
+    grpc_load_reporting_config *lrc,
+    const grpc_load_reporting_call_data *call_data) {
+  lrc->fn(call_data, lrc->user_data);
+}
+
+static bool is_load_reporting_enabled(const grpc_channel_args *a) {
+  if (a == NULL) return false;
+  for (size_t i = 0; i < a->num_args; i++) {
+    if (0 == strcmp(a->args[i].key, GRPC_ARG_ENABLE_LOAD_REPORTING)) {
+      return a->args[i].value.pointer.p != NULL;
+    }
+  }
+  return false;
+}
+
+static bool maybe_add_load_reporting_filter(grpc_channel_stack_builder *builder,
+                                            void *arg) {
+  const grpc_channel_args *args =
+      grpc_channel_stack_builder_get_channel_arguments(builder);
+  if (is_load_reporting_enabled(args)) {
+    return grpc_channel_stack_builder_prepend_filter(
+        builder, (const grpc_channel_filter *)arg, NULL, NULL);
+  }
+  return true;
+}
+
+static void lrd_arg_destroy(void *p) { grpc_load_reporting_config_destroy(p); }
+
+static void *lrd_arg_copy(void *p) {
+  return grpc_load_reporting_config_copy(p);
+}
+
+static int lrd_arg_cmp(void *a, void *b) {
+  grpc_load_reporting_config *lhs = a;
+  grpc_load_reporting_config *rhs = b;
+  return !(lhs->fn == rhs->fn && lhs->user_data == rhs->user_data);
+}
+
+static const grpc_arg_pointer_vtable lrd_ptr_vtable = {
+    lrd_arg_copy, lrd_arg_destroy, lrd_arg_cmp};
+
+grpc_arg grpc_load_reporting_config_create_arg(
+    grpc_load_reporting_config *lrc) {
+  grpc_arg arg;
+  arg.type = GRPC_ARG_POINTER;
+  arg.key = GRPC_ARG_ENABLE_LOAD_REPORTING;
+  arg.value.pointer.p = lrc;
+  arg.value.pointer.vtable = &lrd_ptr_vtable;
+  return arg;
+}
+
+/* Plugin registration */
+
+void grpc_load_reporting_plugin_init(void) {
+  grpc_channel_init_register_stage(GRPC_CLIENT_CHANNEL, INT_MAX,
+                                   maybe_add_load_reporting_filter,
+                                   (void *)&grpc_load_reporting_filter);
+  grpc_channel_init_register_stage(GRPC_SERVER_CHANNEL, INT_MAX,
+                                   maybe_add_load_reporting_filter,
+                                   (void *)&grpc_load_reporting_filter);
+}
+
+void grpc_load_reporting_plugin_shutdown() {}
diff --git a/src/core/ext/load_reporting/load_reporting.h b/src/core/ext/load_reporting/load_reporting.h
new file mode 100644
index 0000000000..316cd89bd7
--- /dev/null
+++ b/src/core/ext/load_reporting/load_reporting.h
@@ -0,0 +1,75 @@
+/*
+ *
+ * Copyright 2016, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#ifndef GRPC_CORE_EXT_LOAD_REPORTING_LOAD_REPORTING_H
+#define GRPC_CORE_EXT_LOAD_REPORTING_LOAD_REPORTING_H
+
+#include "src/core/lib/iomgr/closure.h"
+#include "src/core/lib/surface/call.h"
+
+typedef struct grpc_load_reporting_config grpc_load_reporting_config;
+
+/** Call information to be passed to the provided load reporting function upon
+ * completion of the call */
+typedef struct grpc_load_reporting_call_data {
+  const grpc_call_stats *stats;   /**< Stats for the call */
+  const char *trailing_md_string; /**< LR trailing metadata info */
+} grpc_load_reporting_call_data;
+
+/** Custom function to be called by the load reporting filter. */
+typedef void (*grpc_load_reporting_fn)(
+    const grpc_load_reporting_call_data *call_data, void *user_data);
+
+/** Register \a fn as the function to be invoked by the load reporting filter.
+ * \a fn will be invoked at the beginning and at the end of the call.
+ *
+ * For the first invocation, \a fn's first argument
+ * (grpc_load_reporting_call_data*) will be NULL. \a user_data is always passed
+ * as-is. */
+grpc_load_reporting_config *grpc_load_reporting_config_create(
+    grpc_load_reporting_fn fn, void *user_data);
+
+grpc_load_reporting_config *grpc_load_reporting_config_copy(
+    grpc_load_reporting_config *src);
+
+void grpc_load_reporting_config_destroy(grpc_load_reporting_config *lrc);
+
+/** Invoke the function registered by \a grpc_load_reporting_init. */
+void grpc_load_reporting_config_call(
+    grpc_load_reporting_config *lrc,
+    const grpc_load_reporting_call_data *call_data);
+
+/** Return a \a grpc_arg enabling load reporting */
+grpc_arg grpc_load_reporting_config_create_arg(grpc_load_reporting_config *lrc);
+
+#endif /* GRPC_CORE_EXT_LOAD_REPORTING_LOAD_REPORTING_H */
diff --git a/src/core/ext/load_reporting/load_reporting_filter.c b/src/core/ext/load_reporting/load_reporting_filter.c
new file mode 100644
index 0000000000..f49730fac3
--- /dev/null
+++ b/src/core/ext/load_reporting/load_reporting_filter.c
@@ -0,0 +1,151 @@
+/*
+ *
+ * Copyright 2016, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#include <grpc/support/log.h>
+#include <grpc/support/string_util.h>
+#include <grpc/support/sync.h>
+#include <string.h>
+
+#include "src/core/ext/load_reporting/load_reporting.h"
+#include "src/core/ext/load_reporting/load_reporting_filter.h"
+#include "src/core/lib/channel/channel_args.h"
+#include "src/core/lib/profiling/timers.h"
+#include "src/core/lib/transport/static_metadata.h"
+
+typedef struct call_data { const char *trailing_md_string; } call_data;
+typedef struct channel_data {
+  gpr_mu mu;
+  grpc_load_reporting_config *lrc;
+} channel_data;
+
+static void invoke_lr_fn_locked(grpc_load_reporting_config *lrc,
+                                grpc_load_reporting_call_data *lr_call_data) {
+  GPR_TIMER_BEGIN("load_reporting_config_fn", 0);
+  grpc_load_reporting_config_call(lrc, lr_call_data);
+  GPR_TIMER_END("load_reporting_config_fn", 0);
+}
+
+/* Constructor for call_data */
+static void init_call_elem(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
+                           grpc_call_element_args *args) {
+  call_data *calld = elem->call_data;
+  memset(calld, 0, sizeof(call_data));
+}
+
+/* Destructor for call_data */
+static void destroy_call_elem(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
+                              const grpc_call_stats *stats, void *ignored) {
+  channel_data *chand = elem->channel_data;
+  call_data *calld = elem->call_data;
+
+  grpc_load_reporting_call_data lr_call_data = {stats,
+                                                calld->trailing_md_string};
+
+  gpr_mu_lock(&chand->mu);
+  invoke_lr_fn_locked(chand->lrc, &lr_call_data);
+  gpr_mu_unlock(&chand->mu);
+}
+
+/* Constructor for channel_data */
+static void init_channel_elem(grpc_exec_ctx *exec_ctx,
+                              grpc_channel_element *elem,
+                              grpc_channel_element_args *args) {
+  GPR_ASSERT(!args->is_last);
+
+  channel_data *chand = elem->channel_data;
+  memset(chand, 0, sizeof(channel_data));
+
+  gpr_mu_init(&chand->mu);
+  for (size_t i = 0; i < args->channel_args->num_args; i++) {
+    if (0 == strcmp(args->channel_args->args[i].key,
+                    GRPC_ARG_ENABLE_LOAD_REPORTING)) {
+      grpc_load_reporting_config *arg_lrc =
+          args->channel_args->args[i].value.pointer.p;
+      chand->lrc = grpc_load_reporting_config_copy(arg_lrc);
+      GPR_ASSERT(chand->lrc != NULL);
+      break;
+    }
+  }
+  GPR_ASSERT(chand->lrc != NULL); /* arg actually found */
+
+  gpr_mu_lock(&chand->mu);
+  invoke_lr_fn_locked(chand->lrc, NULL);
+  gpr_mu_unlock(&chand->mu);
+}
+
+/* Destructor for channel data */
+static void destroy_channel_elem(grpc_exec_ctx *exec_ctx,
+                                 grpc_channel_element *elem) {
+  channel_data *chand = elem->channel_data;
+  gpr_mu_destroy(&chand->mu);
+  grpc_load_reporting_config_destroy(chand->lrc);
+}
+
+static grpc_mdelem *lr_trailing_md_filter(void *user_data, grpc_mdelem *md) {
+  grpc_call_element *elem = user_data;
+  call_data *calld = elem->call_data;
+
+  if (md->key == GRPC_MDSTR_LOAD_REPORTING) {
+    calld->trailing_md_string = gpr_strdup(grpc_mdstr_as_c_string(md->value));
+    return NULL;
+  }
+
+  return md;
+}
+
+static void lr_start_transport_stream_op(grpc_exec_ctx *exec_ctx,
+                                         grpc_call_element *elem,
+                                         grpc_transport_stream_op *op) {
+  GPR_TIMER_BEGIN("lr_start_transport_stream_op", 0);
+
+  if (op->send_trailing_metadata) {
+    grpc_metadata_batch_filter(op->send_trailing_metadata,
+                               lr_trailing_md_filter, elem);
+  }
+  grpc_call_next_op(exec_ctx, elem, op);
+
+  GPR_TIMER_END("lr_start_transport_stream_op", 0);
+}
+
+const grpc_channel_filter grpc_load_reporting_filter = {
+    lr_start_transport_stream_op,
+    grpc_channel_next_op,
+    sizeof(call_data),
+    init_call_elem,
+    grpc_call_stack_ignore_set_pollset,
+    destroy_call_elem,
+    sizeof(channel_data),
+    init_channel_elem,
+    destroy_channel_elem,
+    grpc_call_next_get_peer,
+    "load_reporting"};
diff --git a/src/core/ext/load_reporting/load_reporting_filter.h b/src/core/ext/load_reporting/load_reporting_filter.h
new file mode 100644
index 0000000000..f69cd6fdc6
--- /dev/null
+++ b/src/core/ext/load_reporting/load_reporting_filter.h
@@ -0,0 +1,41 @@
+/*
+ *
+ * Copyright 2016, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#ifndef GRPC_CORE_EXT_LOAD_REPORTING_LOAD_REPORTING_FILTER_H
+#define GRPC_CORE_EXT_LOAD_REPORTING_LOAD_REPORTING_FILTER_H
+
+#include "src/core/lib/channel/channel_stack.h"
+
+extern const grpc_channel_filter grpc_load_reporting_filter;
+
+#endif /* GRPC_CORE_EXT_LOAD_REPORTING_LOAD_REPORTING_FILTER_H */
diff --git a/src/core/lib/channel/channel_stack.c b/src/core/lib/channel/channel_stack.c
index ad182d1f69..4892ed283d 100644
--- a/src/core/lib/channel/channel_stack.c
+++ b/src/core/lib/channel/channel_stack.c
@@ -214,6 +214,7 @@ void grpc_call_stack_ignore_set_pollset(grpc_exec_ctx *exec_ctx,
                                         grpc_pollset *pollset) {}
 
 void grpc_call_stack_destroy(grpc_exec_ctx *exec_ctx, grpc_call_stack *stack,
+                             const grpc_call_stats *call_stats,
                              void *and_free_memory) {
   grpc_call_element *elems = CALL_ELEMS_FROM_STACK(stack);
   size_t count = stack->count;
@@ -221,7 +222,7 @@ void grpc_call_stack_destroy(grpc_exec_ctx *exec_ctx, grpc_call_stack *stack,
 
   /* destroy per-filter data */
   for (i = 0; i < count; i++) {
-    elems[i].filter->destroy_call_elem(exec_ctx, &elems[i],
+    elems[i].filter->destroy_call_elem(exec_ctx, &elems[i], call_stats,
                                        i == count - 1 ? and_free_memory : NULL);
   }
 }
diff --git a/src/core/lib/channel/channel_stack.h b/src/core/lib/channel/channel_stack.h
index 36c17cb467..2040002269 100644
--- a/src/core/lib/channel/channel_stack.h
+++ b/src/core/lib/channel/channel_stack.h
@@ -45,6 +45,8 @@
 
 #include <grpc/grpc.h>
 #include <grpc/support/log.h>
+#include <grpc/support/time.h>
+
 #include "src/core/lib/debug/trace.h"
 #include "src/core/lib/transport/transport.h"
 
@@ -67,6 +69,12 @@ typedef struct {
   grpc_call_context_element *context;
 } grpc_call_element_args;
 
+typedef struct {
+  grpc_transport_stream_stats transport_stream_stats;
+  gpr_timespec latency; /* From call creating to enqueing of received status */
+  grpc_status_code final_status;
+} grpc_call_stats;
+
 /* Channel filters specify:
    1. the amount of memory needed in the channel & call (via the sizeof_XXX
       members)
@@ -109,6 +117,7 @@ typedef struct {
      \a and_free_memory that should be passed to gpr_free when destruction
      is complete. */
   void (*destroy_call_elem)(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
+                            const grpc_call_stats *stats,
                             void *and_free_memory);
 
   /* sizeof(per channel data) */
@@ -228,6 +237,7 @@ void grpc_call_stack_set_pollset(grpc_exec_ctx *exec_ctx,
 
 /* Destroy a call stack */
 void grpc_call_stack_destroy(grpc_exec_ctx *exec_ctx, grpc_call_stack *stack,
+                             const grpc_call_stats *call_stats,
                              void *and_free_memory);
 
 /* Ignore set pollset - used by filters to implement the set_pollset method
diff --git a/src/core/lib/channel/compress_filter.c b/src/core/lib/channel/compress_filter.c
index 0e548c61b8..30b18a7274 100644
--- a/src/core/lib/channel/compress_filter.c
+++ b/src/core/lib/channel/compress_filter.c
@@ -271,7 +271,7 @@ static void init_call_elem(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
 
 /* Destructor for call_data */
 static void destroy_call_elem(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
-                              void *ignored) {
+                              const grpc_call_stats *stats, void *ignored) {
   /* grab pointers to our data from the call element */
   call_data *calld = elem->call_data;
   gpr_slice_buffer_destroy(&calld->slices);
diff --git a/src/core/lib/channel/connected_channel.c b/src/core/lib/channel/connected_channel.c
index 68a3a7d6fd..06e87b005f 100644
--- a/src/core/lib/channel/connected_channel.c
+++ b/src/core/lib/channel/connected_channel.c
@@ -103,6 +103,7 @@ static void set_pollset(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
 
 /* Destructor for call_data */
 static void destroy_call_elem(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
+                              const grpc_call_stats *stats,
                               void *and_free_memory) {
   call_data *calld = elem->call_data;
   channel_data *chand = elem->channel_data;
diff --git a/src/core/lib/channel/http_client_filter.c b/src/core/lib/channel/http_client_filter.c
index 516e708d1f..cd9e6e894b 100644
--- a/src/core/lib/channel/http_client_filter.c
+++ b/src/core/lib/channel/http_client_filter.c
@@ -156,7 +156,7 @@ static void init_call_elem(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
 
 /* Destructor for call_data */
 static void destroy_call_elem(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
-                              void *ignored) {}
+                              const grpc_call_stats *stats, void *ignored) {}
 
 static grpc_mdelem *scheme_from_args(const grpc_channel_args *args) {
   unsigned i;
diff --git a/src/core/lib/channel/http_server_filter.c b/src/core/lib/channel/http_server_filter.c
index ba865416de..43d71af473 100644
--- a/src/core/lib/channel/http_server_filter.c
+++ b/src/core/lib/channel/http_server_filter.c
@@ -226,7 +226,7 @@ static void init_call_elem(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
 
 /* Destructor for call_data */
 static void destroy_call_elem(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
-                              void *ignored) {}
+                              const grpc_call_stats *stats, void *ignored) {}
 
 /* Constructor for channel_data */
 static void init_channel_elem(grpc_exec_ctx *exec_ctx,
diff --git a/src/core/lib/security/transport/client_auth_filter.c b/src/core/lib/security/transport/client_auth_filter.c
index e3cbcb4433..27208ebb60 100644
--- a/src/core/lib/security/transport/client_auth_filter.c
+++ b/src/core/lib/security/transport/client_auth_filter.c
@@ -278,7 +278,7 @@ static void set_pollset(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
 
 /* Destructor for call_data */
 static void destroy_call_elem(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
-                              void *ignored) {
+                              const grpc_call_stats *stats, void *ignored) {
   call_data *calld = elem->call_data;
   grpc_call_credentials_unref(calld->creds);
   if (calld->host != NULL) {
diff --git a/src/core/lib/security/transport/server_auth_filter.c b/src/core/lib/security/transport/server_auth_filter.c
index 006a30f0c6..714e0adfc9 100644
--- a/src/core/lib/security/transport/server_auth_filter.c
+++ b/src/core/lib/security/transport/server_auth_filter.c
@@ -225,7 +225,7 @@ static void set_pollset(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
 
 /* Destructor for call_data */
 static void destroy_call_elem(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
-                              void *ignored) {}
+                              const grpc_call_stats *stats, void *ignored) {}
 
 /* Constructor for channel_data */
 static void init_channel_elem(grpc_exec_ctx *exec_ctx,
diff --git a/src/core/lib/surface/call.c b/src/core/lib/surface/call.c
index 34ddfa75ad..74a09cf6ed 100644
--- a/src/core/lib/surface/call.c
+++ b/src/core/lib/surface/call.c
@@ -151,7 +151,7 @@ struct grpc_call {
   received_status status[STATUS_SOURCE_COUNT];
 
   /* Call stats: only valid after trailing metadata received */
-  grpc_transport_stream_stats stats;
+  grpc_call_stats stats;
 
   /* Compression algorithm for the call */
   grpc_compression_algorithm compression_algorithm;
@@ -368,7 +368,7 @@ static void destroy_call(grpc_exec_ctx *exec_ctx, void *call, bool success) {
     GRPC_CQ_INTERNAL_UNREF(c->cq, "bind");
   }
   grpc_channel *channel = c->channel;
-  grpc_call_stack_destroy(exec_ctx, CALL_STACK_FROM_CALL(c), c);
+  grpc_call_stack_destroy(exec_ctx, CALL_STACK_FROM_CALL(c), &c->stats, c);
   GRPC_CHANNEL_INTERNAL_UNREF(exec_ctx, channel, "call");
   GPR_TIMER_END("destroy_call", 0);
 }
@@ -1397,7 +1397,7 @@ static grpc_call_error call_start_batch(grpc_exec_ctx *exec_ctx,
         bctl->recv_final_op = 1;
         stream_op.recv_trailing_metadata =
             &call->metadata_batch[1 /* is_receiving */][1 /* is_trailing */];
-        stream_op.collect_stats = &call->stats;
+        stream_op.collect_stats = &call->stats.transport_stream_stats;
         break;
       case GRPC_OP_RECV_CLOSE_ON_SERVER:
         /* Flag validation: currently allow no flags */
@@ -1419,7 +1419,7 @@ static grpc_call_error call_start_batch(grpc_exec_ctx *exec_ctx,
         bctl->recv_final_op = 1;
         stream_op.recv_trailing_metadata =
             &call->metadata_batch[1 /* is_receiving */][1 /* is_trailing */];
-        stream_op.collect_stats = &call->stats;
+        stream_op.collect_stats = &call->stats.transport_stream_stats;
         break;
     }
   }
diff --git a/src/core/lib/surface/lame_client.c b/src/core/lib/surface/lame_client.c
index f50ec54cea..0f5a762364 100644
--- a/src/core/lib/surface/lame_client.c
+++ b/src/core/lib/surface/lame_client.c
@@ -108,6 +108,7 @@ static void init_call_elem(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
                            grpc_call_element_args *args) {}
 
 static void destroy_call_elem(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
+                              const grpc_call_stats *stats,
                               void *and_free_memory) {
   gpr_free(and_free_memory);
 }
diff --git a/src/core/lib/surface/server.c b/src/core/lib/surface/server.c
index 505b501968..dab7e35748 100644
--- a/src/core/lib/surface/server.c
+++ b/src/core/lib/surface/server.c
@@ -845,7 +845,7 @@ static void init_call_elem(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
 }
 
 static void destroy_call_elem(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
-                              void *ignored) {
+                              const grpc_call_stats *stats, void *ignored) {
   channel_data *chand = elem->channel_data;
   call_data *calld = elem->call_data;
 
diff --git a/src/core/lib/transport/static_metadata.c b/src/core/lib/transport/static_metadata.c
index 73b0041fd4..c5f16e530d 100644
--- a/src/core/lib/transport/static_metadata.c
+++ b/src/core/lib/transport/static_metadata.c
@@ -48,7 +48,7 @@ uintptr_t grpc_static_mdelem_user_data[GRPC_STATIC_MDELEM_COUNT] = {
     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
     0, 0, 0, 0, 0, 0, 4, 8, 6, 2, 4, 8, 6, 0, 0, 0, 0, 0, 0, 0,
     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
-    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
 
 const uint8_t grpc_static_metadata_elem_indices[GRPC_STATIC_MDELEM_COUNT * 2] =
     {11, 35, 10, 35, 12, 35, 12, 49, 13, 35, 14, 35, 15, 35, 16, 35, 17, 35,
@@ -56,10 +56,10 @@ const uint8_t grpc_static_metadata_elem_indices[GRPC_STATIC_MDELEM_COUNT * 2] =
      30, 18, 30, 35, 31, 35, 32, 35, 36, 35, 37, 35, 38, 35, 39, 35, 42, 33,
      42, 34, 42, 48, 42, 53, 42, 54, 42, 55, 42, 56, 43, 33, 43, 48, 43, 53,
      46, 0,  46, 1,  46, 2,  50, 35, 57, 35, 58, 35, 59, 35, 60, 35, 61, 35,
-     62, 35, 63, 35, 64, 35, 65, 35, 66, 40, 66, 68, 66, 71, 67, 79, 67, 80,
-     69, 35, 70, 35, 72, 35, 73, 35, 74, 35, 75, 35, 76, 41, 76, 51, 76, 52,
-     77, 35, 78, 35, 81, 3,  81, 4,  81, 5,  81, 6,  81, 7,  81, 8,  81, 9,
-     82, 35, 83, 84, 85, 35, 86, 35, 87, 35, 88, 35, 89, 35};
+     62, 35, 63, 35, 64, 35, 65, 35, 66, 35, 67, 40, 67, 69, 67, 72, 68, 80,
+     68, 81, 70, 35, 71, 35, 73, 35, 74, 35, 75, 35, 76, 35, 77, 41, 77, 51,
+     77, 52, 78, 35, 79, 35, 82, 3,  82, 4,  82, 5,  82, 6,  82, 7,  82, 8,
+     82, 9,  83, 35, 84, 85, 86, 35, 87, 35, 88, 35, 89, 35, 90, 35};
 
 const char *const grpc_static_metadata_strings[GRPC_STATIC_MDSTR_COUNT] = {
     "0",
@@ -126,6 +126,7 @@ const char *const grpc_static_metadata_strings[GRPC_STATIC_MDSTR_COUNT] = {
     "if-unmodified-since",
     "last-modified",
     "link",
+    "load-reporting",
     "location",
     "max-forwards",
     ":method",
diff --git a/src/core/lib/transport/static_metadata.h b/src/core/lib/transport/static_metadata.h
index f9d8bcdc8f..5ff0d2f3bc 100644
--- a/src/core/lib/transport/static_metadata.h
+++ b/src/core/lib/transport/static_metadata.h
@@ -44,7 +44,7 @@
 
 #include "src/core/lib/transport/metadata.h"
 
-#define GRPC_STATIC_MDSTR_COUNT 90
+#define GRPC_STATIC_MDSTR_COUNT 91
 extern grpc_mdstr grpc_static_mdstr_table[GRPC_STATIC_MDSTR_COUNT];
 /* "0" */
 #define GRPC_MDSTR_0 (&grpc_static_mdstr_table[0])
@@ -175,60 +175,62 @@ extern grpc_mdstr grpc_static_mdstr_table[GRPC_STATIC_MDSTR_COUNT];
 #define GRPC_MDSTR_LAST_MODIFIED (&grpc_static_mdstr_table[62])
 /* "link" */
 #define GRPC_MDSTR_LINK (&grpc_static_mdstr_table[63])
+/* "load-reporting" */
+#define GRPC_MDSTR_LOAD_REPORTING (&grpc_static_mdstr_table[64])
 /* "location" */
-#define GRPC_MDSTR_LOCATION (&grpc_static_mdstr_table[64])
+#define GRPC_MDSTR_LOCATION (&grpc_static_mdstr_table[65])
 /* "max-forwards" */
-#define GRPC_MDSTR_MAX_FORWARDS (&grpc_static_mdstr_table[65])
+#define GRPC_MDSTR_MAX_FORWARDS (&grpc_static_mdstr_table[66])
 /* ":method" */
-#define GRPC_MDSTR_METHOD (&grpc_static_mdstr_table[66])
+#define GRPC_MDSTR_METHOD (&grpc_static_mdstr_table[67])
 /* ":path" */
-#define GRPC_MDSTR_PATH (&grpc_static_mdstr_table[67])
+#define GRPC_MDSTR_PATH (&grpc_static_mdstr_table[68])
 /* "POST" */
-#define GRPC_MDSTR_POST (&grpc_static_mdstr_table[68])
+#define GRPC_MDSTR_POST (&grpc_static_mdstr_table[69])
 /* "proxy-authenticate" */
-#define GRPC_MDSTR_PROXY_AUTHENTICATE (&grpc_static_mdstr_table[69])
+#define GRPC_MDSTR_PROXY_AUTHENTICATE (&grpc_static_mdstr_table[70])
 /* "proxy-authorization" */
-#define GRPC_MDSTR_PROXY_AUTHORIZATION (&grpc_static_mdstr_table[70])
+#define GRPC_MDSTR_PROXY_AUTHORIZATION (&grpc_static_mdstr_table[71])
 /* "PUT" */
-#define GRPC_MDSTR_PUT (&grpc_static_mdstr_table[71])
+#define GRPC_MDSTR_PUT (&grpc_static_mdstr_table[72])
 /* "range" */
-#define GRPC_MDSTR_RANGE (&grpc_static_mdstr_table[72])
+#define GRPC_MDSTR_RANGE (&grpc_static_mdstr_table[73])
 /* "referer" */
-#define GRPC_MDSTR_REFERER (&grpc_static_mdstr_table[73])
+#define GRPC_MDSTR_REFERER (&grpc_static_mdstr_table[74])
 /* "refresh" */
-#define GRPC_MDSTR_REFRESH (&grpc_static_mdstr_table[74])
+#define GRPC_MDSTR_REFRESH (&grpc_static_mdstr_table[75])
 /* "retry-after" */
-#define GRPC_MDSTR_RETRY_AFTER (&grpc_static_mdstr_table[75])
+#define GRPC_MDSTR_RETRY_AFTER (&grpc_static_mdstr_table[76])
 /* ":scheme" */
-#define GRPC_MDSTR_SCHEME (&grpc_static_mdstr_table[76])
+#define GRPC_MDSTR_SCHEME (&grpc_static_mdstr_table[77])
 /* "server" */
-#define GRPC_MDSTR_SERVER (&grpc_static_mdstr_table[77])
+#define GRPC_MDSTR_SERVER (&grpc_static_mdstr_table[78])
 /* "set-cookie" */
-#define GRPC_MDSTR_SET_COOKIE (&grpc_static_mdstr_table[78])
+#define GRPC_MDSTR_SET_COOKIE (&grpc_static_mdstr_table[79])
 /* "/" */
-#define GRPC_MDSTR_SLASH (&grpc_static_mdstr_table[79])
+#define GRPC_MDSTR_SLASH (&grpc_static_mdstr_table[80])
 /* "/index.html" */
-#define GRPC_MDSTR_SLASH_INDEX_DOT_HTML (&grpc_static_mdstr_table[80])
+#define GRPC_MDSTR_SLASH_INDEX_DOT_HTML (&grpc_static_mdstr_table[81])
 /* ":status" */
-#define GRPC_MDSTR_STATUS (&grpc_static_mdstr_table[81])
+#define GRPC_MDSTR_STATUS (&grpc_static_mdstr_table[82])
 /* "strict-transport-security" */
-#define GRPC_MDSTR_STRICT_TRANSPORT_SECURITY (&grpc_static_mdstr_table[82])
+#define GRPC_MDSTR_STRICT_TRANSPORT_SECURITY (&grpc_static_mdstr_table[83])
 /* "te" */
-#define GRPC_MDSTR_TE (&grpc_static_mdstr_table[83])
+#define GRPC_MDSTR_TE (&grpc_static_mdstr_table[84])
 /* "trailers" */
-#define GRPC_MDSTR_TRAILERS (&grpc_static_mdstr_table[84])
+#define GRPC_MDSTR_TRAILERS (&grpc_static_mdstr_table[85])
 /* "transfer-encoding" */
-#define GRPC_MDSTR_TRANSFER_ENCODING (&grpc_static_mdstr_table[85])
+#define GRPC_MDSTR_TRANSFER_ENCODING (&grpc_static_mdstr_table[86])
 /* "user-agent" */
-#define GRPC_MDSTR_USER_AGENT (&grpc_static_mdstr_table[86])
+#define GRPC_MDSTR_USER_AGENT (&grpc_static_mdstr_table[87])
 /* "vary" */
-#define GRPC_MDSTR_VARY (&grpc_static_mdstr_table[87])
+#define GRPC_MDSTR_VARY (&grpc_static_mdstr_table[88])
 /* "via" */
-#define GRPC_MDSTR_VIA (&grpc_static_mdstr_table[88])
+#define GRPC_MDSTR_VIA (&grpc_static_mdstr_table[89])
 /* "www-authenticate" */
-#define GRPC_MDSTR_WWW_AUTHENTICATE (&grpc_static_mdstr_table[89])
+#define GRPC_MDSTR_WWW_AUTHENTICATE (&grpc_static_mdstr_table[90])
 
-#define GRPC_STATIC_MDELEM_COUNT 79
+#define GRPC_STATIC_MDELEM_COUNT 80
 extern grpc_mdelem grpc_static_mdelem_table[GRPC_STATIC_MDELEM_COUNT];
 extern uintptr_t grpc_static_mdelem_user_data[GRPC_STATIC_MDELEM_COUNT];
 /* "accept-charset": "" */
@@ -333,71 +335,73 @@ extern uintptr_t grpc_static_mdelem_user_data[GRPC_STATIC_MDELEM_COUNT];
 #define GRPC_MDELEM_LAST_MODIFIED_EMPTY (&grpc_static_mdelem_table[45])
 /* "link": "" */
 #define GRPC_MDELEM_LINK_EMPTY (&grpc_static_mdelem_table[46])
+/* "load-reporting": "" */
+#define GRPC_MDELEM_LOAD_REPORTING_EMPTY (&grpc_static_mdelem_table[47])
 /* "location": "" */
-#define GRPC_MDELEM_LOCATION_EMPTY (&grpc_static_mdelem_table[47])
+#define GRPC_MDELEM_LOCATION_EMPTY (&grpc_static_mdelem_table[48])
 /* "max-forwards": "" */
-#define GRPC_MDELEM_MAX_FORWARDS_EMPTY (&grpc_static_mdelem_table[48])
+#define GRPC_MDELEM_MAX_FORWARDS_EMPTY (&grpc_static_mdelem_table[49])
 /* ":method": "GET" */
-#define GRPC_MDELEM_METHOD_GET (&grpc_static_mdelem_table[49])
+#define GRPC_MDELEM_METHOD_GET (&grpc_static_mdelem_table[50])
 /* ":method": "POST" */
-#define GRPC_MDELEM_METHOD_POST (&grpc_static_mdelem_table[50])
+#define GRPC_MDELEM_METHOD_POST (&grpc_static_mdelem_table[51])
 /* ":method": "PUT" */
-#define GRPC_MDELEM_METHOD_PUT (&grpc_static_mdelem_table[51])
+#define GRPC_MDELEM_METHOD_PUT (&grpc_static_mdelem_table[52])
 /* ":path": "/" */
-#define GRPC_MDELEM_PATH_SLASH (&grpc_static_mdelem_table[52])
+#define GRPC_MDELEM_PATH_SLASH (&grpc_static_mdelem_table[53])
 /* ":path": "/index.html" */
-#define GRPC_MDELEM_PATH_SLASH_INDEX_DOT_HTML (&grpc_static_mdelem_table[53])
+#define GRPC_MDELEM_PATH_SLASH_INDEX_DOT_HTML (&grpc_static_mdelem_table[54])
 /* "proxy-authenticate": "" */
-#define GRPC_MDELEM_PROXY_AUTHENTICATE_EMPTY (&grpc_static_mdelem_table[54])
+#define GRPC_MDELEM_PROXY_AUTHENTICATE_EMPTY (&grpc_static_mdelem_table[55])
 /* "proxy-authorization": "" */
-#define GRPC_MDELEM_PROXY_AUTHORIZATION_EMPTY (&grpc_static_mdelem_table[55])
+#define GRPC_MDELEM_PROXY_AUTHORIZATION_EMPTY (&grpc_static_mdelem_table[56])
 /* "range": "" */
-#define GRPC_MDELEM_RANGE_EMPTY (&grpc_static_mdelem_table[56])
+#define GRPC_MDELEM_RANGE_EMPTY (&grpc_static_mdelem_table[57])
 /* "referer": "" */
-#define GRPC_MDELEM_REFERER_EMPTY (&grpc_static_mdelem_table[57])
+#define GRPC_MDELEM_REFERER_EMPTY (&grpc_static_mdelem_table[58])
 /* "refresh": "" */
-#define GRPC_MDELEM_REFRESH_EMPTY (&grpc_static_mdelem_table[58])
+#define GRPC_MDELEM_REFRESH_EMPTY (&grpc_static_mdelem_table[59])
 /* "retry-after": "" */
-#define GRPC_MDELEM_RETRY_AFTER_EMPTY (&grpc_static_mdelem_table[59])
+#define GRPC_MDELEM_RETRY_AFTER_EMPTY (&grpc_static_mdelem_table[60])
 /* ":scheme": "grpc" */
-#define GRPC_MDELEM_SCHEME_GRPC (&grpc_static_mdelem_table[60])
+#define GRPC_MDELEM_SCHEME_GRPC (&grpc_static_mdelem_table[61])
 /* ":scheme": "http" */
-#define GRPC_MDELEM_SCHEME_HTTP (&grpc_static_mdelem_table[61])
+#define GRPC_MDELEM_SCHEME_HTTP (&grpc_static_mdelem_table[62])
 /* ":scheme": "https" */
-#define GRPC_MDELEM_SCHEME_HTTPS (&grpc_static_mdelem_table[62])
+#define GRPC_MDELEM_SCHEME_HTTPS (&grpc_static_mdelem_table[63])
 /* "server": "" */
-#define GRPC_MDELEM_SERVER_EMPTY (&grpc_static_mdelem_table[63])
+#define GRPC_MDELEM_SERVER_EMPTY (&grpc_static_mdelem_table[64])
 /* "set-cookie": "" */
-#define GRPC_MDELEM_SET_COOKIE_EMPTY (&grpc_static_mdelem_table[64])
+#define GRPC_MDELEM_SET_COOKIE_EMPTY (&grpc_static_mdelem_table[65])
 /* ":status": "200" */
-#define GRPC_MDELEM_STATUS_200 (&grpc_static_mdelem_table[65])
+#define GRPC_MDELEM_STATUS_200 (&grpc_static_mdelem_table[66])
 /* ":status": "204" */
-#define GRPC_MDELEM_STATUS_204 (&grpc_static_mdelem_table[66])
+#define GRPC_MDELEM_STATUS_204 (&grpc_static_mdelem_table[67])
 /* ":status": "206" */
-#define GRPC_MDELEM_STATUS_206 (&grpc_static_mdelem_table[67])
+#define GRPC_MDELEM_STATUS_206 (&grpc_static_mdelem_table[68])
 /* ":status": "304" */
-#define GRPC_MDELEM_STATUS_304 (&grpc_static_mdelem_table[68])
+#define GRPC_MDELEM_STATUS_304 (&grpc_static_mdelem_table[69])
 /* ":status": "400" */
-#define GRPC_MDELEM_STATUS_400 (&grpc_static_mdelem_table[69])
+#define GRPC_MDELEM_STATUS_400 (&grpc_static_mdelem_table[70])
 /* ":status": "404" */
-#define GRPC_MDELEM_STATUS_404 (&grpc_static_mdelem_table[70])
+#define GRPC_MDELEM_STATUS_404 (&grpc_static_mdelem_table[71])
 /* ":status": "500" */
-#define GRPC_MDELEM_STATUS_500 (&grpc_static_mdelem_table[71])
+#define GRPC_MDELEM_STATUS_500 (&grpc_static_mdelem_table[72])
 /* "strict-transport-security": "" */
 #define GRPC_MDELEM_STRICT_TRANSPORT_SECURITY_EMPTY \
-  (&grpc_static_mdelem_table[72])
+  (&grpc_static_mdelem_table[73])
 /* "te": "trailers" */
-#define GRPC_MDELEM_TE_TRAILERS (&grpc_static_mdelem_table[73])
+#define GRPC_MDELEM_TE_TRAILERS (&grpc_static_mdelem_table[74])
 /* "transfer-encoding": "" */
-#define GRPC_MDELEM_TRANSFER_ENCODING_EMPTY (&grpc_static_mdelem_table[74])
+#define GRPC_MDELEM_TRANSFER_ENCODING_EMPTY (&grpc_static_mdelem_table[75])
 /* "user-agent": "" */
-#define GRPC_MDELEM_USER_AGENT_EMPTY (&grpc_static_mdelem_table[75])
+#define GRPC_MDELEM_USER_AGENT_EMPTY (&grpc_static_mdelem_table[76])
 /* "vary": "" */
-#define GRPC_MDELEM_VARY_EMPTY (&grpc_static_mdelem_table[76])
+#define GRPC_MDELEM_VARY_EMPTY (&grpc_static_mdelem_table[77])
 /* "via": "" */
-#define GRPC_MDELEM_VIA_EMPTY (&grpc_static_mdelem_table[77])
+#define GRPC_MDELEM_VIA_EMPTY (&grpc_static_mdelem_table[78])
 /* "www-authenticate": "" */
-#define GRPC_MDELEM_WWW_AUTHENTICATE_EMPTY (&grpc_static_mdelem_table[78])
+#define GRPC_MDELEM_WWW_AUTHENTICATE_EMPTY (&grpc_static_mdelem_table[79])
 
 extern const uint8_t
     grpc_static_metadata_elem_indices[GRPC_STATIC_MDELEM_COUNT * 2];
diff --git a/src/core/plugin_registry/grpc_plugin_registry.c b/src/core/plugin_registry/grpc_plugin_registry.c
index 822aa6d8b7..905cd59e23 100644
--- a/src/core/plugin_registry/grpc_plugin_registry.c
+++ b/src/core/plugin_registry/grpc_plugin_registry.c
@@ -45,6 +45,8 @@ extern void grpc_resolver_dns_native_init(void);
 extern void grpc_resolver_dns_native_shutdown(void);
 extern void grpc_resolver_sockaddr_init(void);
 extern void grpc_resolver_sockaddr_shutdown(void);
+extern void grpc_load_reporting_plugin_init(void);
+extern void grpc_load_reporting_plugin_shutdown(void);
 extern void census_grpc_plugin_init(void);
 extern void census_grpc_plugin_shutdown(void);
 
@@ -61,6 +63,8 @@ void grpc_register_built_in_plugins(void) {
                        grpc_resolver_dns_native_shutdown);
   grpc_register_plugin(grpc_resolver_sockaddr_init,
                        grpc_resolver_sockaddr_shutdown);
+  grpc_register_plugin(grpc_load_reporting_plugin_init,
+                       grpc_load_reporting_plugin_shutdown);
   grpc_register_plugin(census_grpc_plugin_init,
                        census_grpc_plugin_shutdown);
 }
diff --git a/src/core/plugin_registry/grpc_unsecure_plugin_registry.c b/src/core/plugin_registry/grpc_unsecure_plugin_registry.c
index a6108ae7a9..7995078725 100644
--- a/src/core/plugin_registry/grpc_unsecure_plugin_registry.c
+++ b/src/core/plugin_registry/grpc_unsecure_plugin_registry.c
@@ -41,6 +41,8 @@ extern void grpc_resolver_dns_native_init(void);
 extern void grpc_resolver_dns_native_shutdown(void);
 extern void grpc_resolver_sockaddr_init(void);
 extern void grpc_resolver_sockaddr_shutdown(void);
+extern void grpc_load_reporting_plugin_init(void);
+extern void grpc_load_reporting_plugin_shutdown(void);
 extern void grpc_lb_policy_pick_first_init(void);
 extern void grpc_lb_policy_pick_first_shutdown(void);
 extern void grpc_lb_policy_round_robin_init(void);
@@ -57,6 +59,8 @@ void grpc_register_built_in_plugins(void) {
                        grpc_resolver_dns_native_shutdown);
   grpc_register_plugin(grpc_resolver_sockaddr_init,
                        grpc_resolver_sockaddr_shutdown);
+  grpc_register_plugin(grpc_load_reporting_plugin_init,
+                       grpc_load_reporting_plugin_shutdown);
   grpc_register_plugin(grpc_lb_policy_pick_first_init,
                        grpc_lb_policy_pick_first_shutdown);
   grpc_register_plugin(grpc_lb_policy_round_robin_init,