Merge pull request #9850 from markdroth/retry_throttle

Retry throttling implementation.

BUILD

@@ -310,6 +310,7 @@ grpc_cc_library(
         "src/core/lib/profiling/stap_timers.c",
         "src/core/lib/support/arena.c",
         "src/core/lib/support/alloc.c",
+        "src/core/lib/support/atm.c",
         "src/core/lib/support/avl.c",
         "src/core/lib/support/backoff.c",
         "src/core/lib/support/cmdline.c",
@@ -698,6 +699,7 @@ grpc_cc_library(
         "src/core/ext/client_channel/resolver.c",
         "src/core/ext/client_channel/resolver_factory.c",
         "src/core/ext/client_channel/resolver_registry.c",
+        "src/core/ext/client_channel/retry_throttle.c",
         "src/core/ext/client_channel/subchannel.c",
         "src/core/ext/client_channel/subchannel_index.c",
         "src/core/ext/client_channel/uri_parser.c",
@@ -718,6 +720,7 @@ grpc_cc_library(
         "src/core/ext/client_channel/resolver.h",
         "src/core/ext/client_channel/resolver_factory.h",
         "src/core/ext/client_channel/resolver_registry.h",
+        "src/core/ext/client_channel/retry_throttle.h",
         "src/core/ext/client_channel/subchannel.h",
         "src/core/ext/client_channel/subchannel_index.h",
         "src/core/ext/client_channel/uri_parser.h",

CMakeLists.txt

@@ -698,6 +698,7 @@ add_library(gpr
   src/core/lib/profiling/stap_timers.c
   src/core/lib/support/alloc.c
   src/core/lib/support/arena.c
+  src/core/lib/support/atm.c
   src/core/lib/support/avl.c
   src/core/lib/support/backoff.c
   src/core/lib/support/cmdline.c
@@ -1054,6 +1055,7 @@ add_library(grpc
   src/core/ext/client_channel/resolver.c
   src/core/ext/client_channel/resolver_factory.c
   src/core/ext/client_channel/resolver_registry.c
+  src/core/ext/client_channel/retry_throttle.c
   src/core/ext/client_channel/subchannel.c
   src/core/ext/client_channel/subchannel_index.c
   src/core/ext/client_channel/uri_parser.c
@@ -1339,6 +1341,7 @@ add_library(grpc_cronet
   src/core/ext/client_channel/resolver.c
   src/core/ext/client_channel/resolver_factory.c
   src/core/ext/client_channel/resolver_registry.c
+  src/core/ext/client_channel/retry_throttle.c
   src/core/ext/client_channel/subchannel.c
   src/core/ext/client_channel/subchannel_index.c
   src/core/ext/client_channel/uri_parser.c
@@ -1893,6 +1896,7 @@ add_library(grpc_unsecure
   src/core/ext/client_channel/resolver.c
   src/core/ext/client_channel/resolver_factory.c
   src/core/ext/client_channel/resolver_registry.c
+  src/core/ext/client_channel/retry_throttle.c
   src/core/ext/client_channel/subchannel.c
   src/core/ext/client_channel/subchannel_index.c
   src/core/ext/client_channel/uri_parser.c
@@ -2477,6 +2481,7 @@ add_library(grpc++_cronet
   src/core/ext/client_channel/resolver.c
   src/core/ext/client_channel/resolver_factory.c
   src/core/ext/client_channel/resolver_registry.c
+  src/core/ext/client_channel/retry_throttle.c
   src/core/ext/client_channel/subchannel.c
   src/core/ext/client_channel/subchannel_index.c
   src/core/ext/client_channel/uri_parser.c

Makefile

@@ -2609,6 +2609,7 @@ LIBGPR_SRC = \
     src/core/lib/profiling/stap_timers.c \
     src/core/lib/support/alloc.c \
     src/core/lib/support/arena.c \
+    src/core/lib/support/atm.c \
     src/core/lib/support/avl.c \
     src/core/lib/support/backoff.c \
     src/core/lib/support/cmdline.c \
@@ -2946,6 +2947,7 @@ LIBGRPC_SRC = \
     src/core/ext/client_channel/resolver.c \
     src/core/ext/client_channel/resolver_factory.c \
     src/core/ext/client_channel/resolver_registry.c \
+    src/core/ext/client_channel/retry_throttle.c \
     src/core/ext/client_channel/subchannel.c \
     src/core/ext/client_channel/subchannel_index.c \
     src/core/ext/client_channel/uri_parser.c \
@@ -3234,6 +3236,7 @@ LIBGRPC_CRONET_SRC = \
     src/core/ext/client_channel/resolver.c \
     src/core/ext/client_channel/resolver_factory.c \
     src/core/ext/client_channel/resolver_registry.c \
+    src/core/ext/client_channel/retry_throttle.c \
     src/core/ext/client_channel/subchannel.c \
     src/core/ext/client_channel/subchannel_index.c \
     src/core/ext/client_channel/uri_parser.c \
@@ -3771,6 +3774,7 @@ LIBGRPC_UNSECURE_SRC = \
     src/core/ext/client_channel/resolver.c \
     src/core/ext/client_channel/resolver_factory.c \
     src/core/ext/client_channel/resolver_registry.c \
+    src/core/ext/client_channel/retry_throttle.c \
     src/core/ext/client_channel/subchannel.c \
     src/core/ext/client_channel/subchannel_index.c \
     src/core/ext/client_channel/uri_parser.c \
@@ -4357,6 +4361,7 @@ LIBGRPC++_CRONET_SRC = \
     src/core/ext/client_channel/resolver.c \
     src/core/ext/client_channel/resolver_factory.c \
     src/core/ext/client_channel/resolver_registry.c \
+    src/core/ext/client_channel/retry_throttle.c \
     src/core/ext/client_channel/subchannel.c \
     src/core/ext/client_channel/subchannel_index.c \
     src/core/ext/client_channel/uri_parser.c \

binding.gyp

@@ -545,6 +545,7 @@
         'src/core/lib/profiling/stap_timers.c',
         'src/core/lib/support/alloc.c',
         'src/core/lib/support/arena.c',
+        'src/core/lib/support/atm.c',
         'src/core/lib/support/avl.c',
         'src/core/lib/support/backoff.c',
         'src/core/lib/support/cmdline.c',
@@ -800,6 +801,7 @@
         'src/core/ext/client_channel/resolver.c',
         'src/core/ext/client_channel/resolver_factory.c',
         'src/core/ext/client_channel/resolver_registry.c',
+        'src/core/ext/client_channel/retry_throttle.c',
         'src/core/ext/client_channel/subchannel.c',
         'src/core/ext/client_channel/subchannel_index.c',
         'src/core/ext/client_channel/uri_parser.c',

build.yaml

@@ -103,6 +103,7 @@ filegroups:
   - src/core/lib/profiling/stap_timers.c
   - src/core/lib/support/alloc.c
   - src/core/lib/support/arena.c
+  - src/core/lib/support/atm.c
   - src/core/lib/support/avl.c
   - src/core/lib/support/backoff.c
   - src/core/lib/support/cmdline.c
@@ -423,6 +424,7 @@ filegroups:
   - src/core/ext/client_channel/resolver.h
   - src/core/ext/client_channel/resolver_factory.h
   - src/core/ext/client_channel/resolver_registry.h
+  - src/core/ext/client_channel/retry_throttle.h
   - src/core/ext/client_channel/subchannel.h
   - src/core/ext/client_channel/subchannel_index.h
   - src/core/ext/client_channel/uri_parser.h
@@ -445,6 +447,7 @@ filegroups:
   - src/core/ext/client_channel/resolver.c
   - src/core/ext/client_channel/resolver_factory.c
   - src/core/ext/client_channel/resolver_registry.c
+  - src/core/ext/client_channel/retry_throttle.c
   - src/core/ext/client_channel/subchannel.c
   - src/core/ext/client_channel/subchannel_index.c
   - src/core/ext/client_channel/uri_parser.c

config.m4

@@ -40,6 +40,7 @@ if test "$PHP_GRPC" != "no"; then
     src/core/lib/profiling/stap_timers.c \
     src/core/lib/support/alloc.c \
     src/core/lib/support/arena.c \
+    src/core/lib/support/atm.c \
     src/core/lib/support/avl.c \
     src/core/lib/support/backoff.c \
     src/core/lib/support/cmdline.c \
@@ -273,6 +274,7 @@ if test "$PHP_GRPC" != "no"; then
     src/core/ext/client_channel/resolver.c \
     src/core/ext/client_channel/resolver_factory.c \
     src/core/ext/client_channel/resolver_registry.c \
+    src/core/ext/client_channel/retry_throttle.c \
     src/core/ext/client_channel/subchannel.c \
     src/core/ext/client_channel/subchannel_index.c \
     src/core/ext/client_channel/uri_parser.c \

gRPC-Core.podspec

@@ -213,6 +213,7 @@ Pod::Spec.new do |s|
                       'src/core/lib/profiling/stap_timers.c',
                       'src/core/lib/support/alloc.c',
                       'src/core/lib/support/arena.c',
+                      'src/core/lib/support/atm.c',
                       'src/core/lib/support/avl.c',
                       'src/core/lib/support/backoff.c',
                       'src/core/lib/support/cmdline.c',
@@ -421,6 +422,7 @@ Pod::Spec.new do |s|
                       'src/core/ext/client_channel/resolver.h',
                       'src/core/ext/client_channel/resolver_factory.h',
                       'src/core/ext/client_channel/resolver_registry.h',
+                      'src/core/ext/client_channel/retry_throttle.h',
                       'src/core/ext/client_channel/subchannel.h',
                       'src/core/ext/client_channel/subchannel_index.h',
                       'src/core/ext/client_channel/uri_parser.h',
@@ -643,6 +645,7 @@ Pod::Spec.new do |s|
                       'src/core/ext/client_channel/resolver.c',
                       'src/core/ext/client_channel/resolver_factory.c',
                       'src/core/ext/client_channel/resolver_registry.c',
+                      'src/core/ext/client_channel/retry_throttle.c',
                       'src/core/ext/client_channel/subchannel.c',
                       'src/core/ext/client_channel/subchannel_index.c',
                       'src/core/ext/client_channel/uri_parser.c',
@@ -861,6 +864,7 @@ Pod::Spec.new do |s|
                               'src/core/ext/client_channel/resolver.h',
                               'src/core/ext/client_channel/resolver_factory.h',
                               'src/core/ext/client_channel/resolver_registry.h',
+                              'src/core/ext/client_channel/retry_throttle.h',
                               'src/core/ext/client_channel/subchannel.h',
                               'src/core/ext/client_channel/subchannel_index.h',
                               'src/core/ext/client_channel/uri_parser.h',

grpc.gemspec

@@ -99,6 +99,7 @@ Gem::Specification.new do |s|
   s.files += %w( src/core/lib/profiling/stap_timers.c )
   s.files += %w( src/core/lib/support/alloc.c )
   s.files += %w( src/core/lib/support/arena.c )
+  s.files += %w( src/core/lib/support/atm.c )
   s.files += %w( src/core/lib/support/avl.c )
   s.files += %w( src/core/lib/support/backoff.c )
   s.files += %w( src/core/lib/support/cmdline.c )
@@ -338,6 +339,7 @@ Gem::Specification.new do |s|
   s.files += %w( src/core/ext/client_channel/resolver.h )
   s.files += %w( src/core/ext/client_channel/resolver_factory.h )
   s.files += %w( src/core/ext/client_channel/resolver_registry.h )
+  s.files += %w( src/core/ext/client_channel/retry_throttle.h )
   s.files += %w( src/core/ext/client_channel/subchannel.h )
   s.files += %w( src/core/ext/client_channel/subchannel_index.h )
   s.files += %w( src/core/ext/client_channel/uri_parser.h )
@@ -560,6 +562,7 @@ Gem::Specification.new do |s|
   s.files += %w( src/core/ext/client_channel/resolver.c )
   s.files += %w( src/core/ext/client_channel/resolver_factory.c )
   s.files += %w( src/core/ext/client_channel/resolver_registry.c )
+  s.files += %w( src/core/ext/client_channel/retry_throttle.c )
   s.files += %w( src/core/ext/client_channel/subchannel.c )
   s.files += %w( src/core/ext/client_channel/subchannel_index.c )
   s.files += %w( src/core/ext/client_channel/uri_parser.c )

include/grpc/impl/codegen/atm.h

@@ -92,4 +92,9 @@
 #error could not determine platform for atm
 #endif
 
+/** Adds \a delta to \a *value, clamping the result to the range specified
+    by \a min and \a max.  Returns the new value. */
+gpr_atm gpr_atm_no_barrier_clamped_add(gpr_atm *value, gpr_atm delta,
+                                       gpr_atm min, gpr_atm max);
+
 #endif /* GRPC_IMPL_CODEGEN_ATM_H */

package.xml

@@ -108,6 +108,7 @@
     <file baseinstalldir="/" name="src/core/lib/profiling/stap_timers.c" role="src" />
     <file baseinstalldir="/" name="src/core/lib/support/alloc.c" role="src" />
     <file baseinstalldir="/" name="src/core/lib/support/arena.c" role="src" />
+    <file baseinstalldir="/" name="src/core/lib/support/atm.c" role="src" />
     <file baseinstalldir="/" name="src/core/lib/support/avl.c" role="src" />
     <file baseinstalldir="/" name="src/core/lib/support/backoff.c" role="src" />
     <file baseinstalldir="/" name="src/core/lib/support/cmdline.c" role="src" />
@@ -347,6 +348,7 @@
     <file baseinstalldir="/" name="src/core/ext/client_channel/resolver.h" role="src" />
     <file baseinstalldir="/" name="src/core/ext/client_channel/resolver_factory.h" role="src" />
     <file baseinstalldir="/" name="src/core/ext/client_channel/resolver_registry.h" role="src" />
+    <file baseinstalldir="/" name="src/core/ext/client_channel/retry_throttle.h" role="src" />
     <file baseinstalldir="/" name="src/core/ext/client_channel/subchannel.h" role="src" />
     <file baseinstalldir="/" name="src/core/ext/client_channel/subchannel_index.h" role="src" />
     <file baseinstalldir="/" name="src/core/ext/client_channel/uri_parser.h" role="src" />
@@ -569,6 +571,7 @@
     <file baseinstalldir="/" name="src/core/ext/client_channel/resolver.c" role="src" />
     <file baseinstalldir="/" name="src/core/ext/client_channel/resolver_factory.c" role="src" />
     <file baseinstalldir="/" name="src/core/ext/client_channel/resolver_registry.c" role="src" />
+    <file baseinstalldir="/" name="src/core/ext/client_channel/retry_throttle.c" role="src" />
     <file baseinstalldir="/" name="src/core/ext/client_channel/subchannel.c" role="src" />
     <file baseinstalldir="/" name="src/core/ext/client_channel/subchannel_index.c" role="src" />
     <file baseinstalldir="/" name="src/core/ext/client_channel/uri_parser.c" role="src" />

src/core/ext/client_channel/client_channel.c

@@ -47,6 +47,7 @@
 #include "src/core/ext/client_channel/lb_policy_registry.h"
 #include "src/core/ext/client_channel/proxy_mapper_registry.h"
 #include "src/core/ext/client_channel/resolver_registry.h"
+#include "src/core/ext/client_channel/retry_throttle.h"
 #include "src/core/ext/client_channel/subchannel.h"
 #include "src/core/lib/channel/channel_args.h"
 #include "src/core/lib/channel/connected_channel.h"
@@ -189,6 +190,8 @@ typedef struct client_channel_channel_data {
   grpc_combiner *combiner;
   /** currently active load balancer */
   grpc_lb_policy *lb_policy;
+  /** retry throttle data */
+  grpc_server_retry_throttle_data *retry_throttle_data;
   /** maps method names to method_parameters structs */
   grpc_slice_hash_table *method_params_table;
   /** incoming resolver result - set by resolver.next() */
@@ -284,6 +287,65 @@ static void watch_lb_policy_locked(grpc_exec_ctx *exec_ctx, channel_data *chand,
                                                &w->on_changed);
 }
 
+typedef struct {
+  char *server_name;
+  grpc_server_retry_throttle_data *retry_throttle_data;
+} service_config_parsing_state;
+
+static void parse_retry_throttle_params(const grpc_json *field, void *arg) {
+  service_config_parsing_state *parsing_state = arg;
+  if (strcmp(field->key, "retryThrottling") == 0) {
+    if (parsing_state->retry_throttle_data != NULL) return;  // Duplicate.
+    if (field->type != GRPC_JSON_OBJECT) return;
+    int max_milli_tokens = 0;
+    int milli_token_ratio = 0;
+    for (grpc_json *sub_field = field->child; sub_field != NULL;
+         sub_field = sub_field->next) {
+      if (sub_field->key == NULL) return;
+      if (strcmp(sub_field->key, "maxTokens") == 0) {
+        if (max_milli_tokens != 0) return;  // Duplicate.
+        if (sub_field->type != GRPC_JSON_NUMBER) return;
+        max_milli_tokens = gpr_parse_nonnegative_int(sub_field->value);
+        if (max_milli_tokens == -1) return;
+        max_milli_tokens *= 1000;
+      } else if (strcmp(sub_field->key, "tokenRatio") == 0) {
+        if (milli_token_ratio != 0) return;  // Duplicate.
+        if (sub_field->type != GRPC_JSON_NUMBER) return;
+        // We support up to 3 decimal digits.
+        size_t whole_len = strlen(sub_field->value);
+        uint32_t multiplier = 1;
+        uint32_t decimal_value = 0;
+        const char *decimal_point = strchr(sub_field->value, '.');
+        if (decimal_point != NULL) {
+          whole_len = (size_t)(decimal_point - sub_field->value);
+          multiplier = 1000;
+          size_t decimal_len = strlen(decimal_point + 1);
+          if (decimal_len > 3) decimal_len = 3;
+          if (!gpr_parse_bytes_to_uint32(decimal_point + 1, decimal_len,
+                                         &decimal_value)) {
+            return;
+          }
+          uint32_t decimal_multiplier = 1;
+          for (size_t i = 0; i < (3 - decimal_len); ++i) {
+            decimal_multiplier *= 10;
+          }
+          decimal_value *= decimal_multiplier;
+        }
+        uint32_t whole_value;
+        if (!gpr_parse_bytes_to_uint32(sub_field->value, whole_len,
+                                       &whole_value)) {
+          return;
+        }
+        milli_token_ratio = (int)((whole_value * multiplier) + decimal_value);
+        if (milli_token_ratio <= 0) return;
+      }
+    }
+    parsing_state->retry_throttle_data =
+        grpc_retry_throttle_map_get_data_for_server(
+            parsing_state->server_name, max_milli_tokens, milli_token_ratio);
+  }
+}
+
 static void on_resolver_result_changed_locked(grpc_exec_ctx *exec_ctx,
                                               void *arg, grpc_error *error) {
   channel_data *chand = arg;
@@ -295,6 +357,8 @@ static void on_resolver_result_changed_locked(grpc_exec_ctx *exec_ctx,
   bool exit_idle = false;
   grpc_error *state_error = GRPC_ERROR_CREATE("No load balancing policy");
   char *service_config_json = NULL;
+  service_config_parsing_state parsing_state;
+  memset(&parsing_state, 0, sizeof(parsing_state));
 
   if (chand->resolver_result != NULL) {
     // Find LB policy name.
@@ -355,6 +419,19 @@ static void on_resolver_result_changed_locked(grpc_exec_ctx *exec_ctx,
       grpc_service_config *service_config =
           grpc_service_config_create(service_config_json);
       if (service_config != NULL) {
+        channel_arg =
+            grpc_channel_args_find(chand->resolver_result, GRPC_ARG_SERVER_URI);
+        GPR_ASSERT(channel_arg != NULL);
+        GPR_ASSERT(channel_arg->type == GRPC_ARG_STRING);
+        grpc_uri *uri =
+            grpc_uri_parse(exec_ctx, channel_arg->value.string, true);
+        GPR_ASSERT(uri->path[0] != '\0');
+        parsing_state.server_name =
+            uri->path[0] == '/' ? uri->path + 1 : uri->path;
+        grpc_service_config_parse_global_params(
+            service_config, parse_retry_throttle_params, &parsing_state);
+        parsing_state.server_name = NULL;
+        grpc_uri_destroy(uri);
         method_params_table = grpc_service_config_create_method_config_table(
             exec_ctx, service_config, method_parameters_create_from_json,
             &method_parameters_vtable);
@@ -386,6 +463,11 @@ static void on_resolver_result_changed_locked(grpc_exec_ctx *exec_ctx,
     chand->info_service_config_json = service_config_json;
   }
   gpr_mu_unlock(&chand->info_mu);
+
+  if (chand->retry_throttle_data != NULL) {
+    grpc_server_retry_throttle_data_unref(chand->retry_throttle_data);
+  }
+  chand->retry_throttle_data = parsing_state.retry_throttle_data;
   if (chand->method_params_table != NULL) {
     grpc_slice_hash_table_unref(exec_ctx, chand->method_params_table);
   }
@@ -613,6 +695,9 @@ static void cc_destroy_channel_elem(grpc_exec_ctx *exec_ctx,
   }
   gpr_free(chand->info_lb_policy_name);
   gpr_free(chand->info_service_config_json);
+  if (chand->retry_throttle_data != NULL) {
+    grpc_server_retry_throttle_data_unref(chand->retry_throttle_data);
+  }
   if (chand->method_params_table != NULL) {
     grpc_slice_hash_table_unref(exec_ctx, chand->method_params_table);
   }
@@ -654,6 +739,7 @@ typedef struct client_channel_call_data {
   grpc_slice path;  // Request path.
   gpr_timespec call_start_time;
   gpr_timespec deadline;
+  grpc_server_retry_throttle_data *retry_throttle_data;
   method_parameters *method_params;
 
   grpc_error *cancel_error;
@@ -676,6 +762,9 @@ typedef struct client_channel_call_data {
   grpc_call_stack *owning_call;
 
   grpc_linked_mdelem lb_token_mdelem;
+
+  grpc_closure on_complete;
+  grpc_closure *original_on_complete;
 } call_data;
 
 grpc_subchannel_call *grpc_client_channel_get_subchannel_call(
@@ -728,7 +817,7 @@ static void retry_waiting_locked(grpc_exec_ctx *exec_ctx, call_data *calld) {
   gpr_free(ops);
 }
 
-// Sets calld->method_params.
+// Sets calld->method_params and calld->retry_throttle_data.
 // If the method params specify a timeout, populates
 // *per_method_deadline and returns true.
 static bool set_call_method_params_from_service_config_locked(
@@ -736,6 +825,10 @@ static bool set_call_method_params_from_service_config_locked(
     gpr_timespec *per_method_deadline) {
   channel_data *chand = elem->channel_data;
   call_data *calld = elem->call_data;
+  if (chand->retry_throttle_data != NULL) {
+    calld->retry_throttle_data =
+        grpc_server_retry_throttle_data_ref(chand->retry_throttle_data);
+  }
   if (chand->method_params_table != NULL) {
     calld->method_params = grpc_method_config_table_get(
         exec_ctx, chand->method_params_table, calld->path);
@@ -1056,6 +1149,26 @@ static void start_transport_stream_op_locked_inner(grpc_exec_ctx *exec_ctx,
   add_waiting_locked(calld, op);
 }
 
+static void on_complete(grpc_exec_ctx *exec_ctx, void *arg, grpc_error *error) {
+  grpc_call_element *elem = arg;
+  call_data *calld = elem->call_data;
+  if (calld->retry_throttle_data != NULL) {
+    if (error == GRPC_ERROR_NONE) {
+      grpc_server_retry_throttle_data_record_success(
+          calld->retry_throttle_data);
+    } else {
+      // TODO(roth): In a subsequent PR, check the return value here and
+      // decide whether or not to retry.  Note that we should only
+      // record failures whose statuses match the configured retryable
+      // or non-fatal status codes.
+      grpc_server_retry_throttle_data_record_failure(
+          calld->retry_throttle_data);
+    }
+  }
+  grpc_closure_run(exec_ctx, calld->original_on_complete,
+                   GRPC_ERROR_REF(error));
+}
+
 static void start_transport_stream_op_locked(grpc_exec_ctx *exec_ctx, void *arg,
                                              grpc_error *error_ignored) {
   GPR_TIMER_BEGIN("start_transport_stream_op_locked", 0);
@@ -1064,6 +1177,14 @@ static void start_transport_stream_op_locked(grpc_exec_ctx *exec_ctx, void *arg,
   grpc_call_element *elem = op->handler_private.args[0];
   call_data *calld = elem->call_data;
 
+  if (op->recv_trailing_metadata != NULL) {
+    GPR_ASSERT(op->on_complete != NULL);
+    calld->original_on_complete = op->on_complete;
+    grpc_closure_init(&calld->on_complete, on_complete, elem,
+                      grpc_schedule_on_exec_ctx);
+    op->on_complete = &calld->on_complete;
+  }
+
   start_transport_stream_op_locked_inner(exec_ctx, op, elem);
 
   GRPC_CALL_STACK_UNREF(exec_ctx, calld->owning_call,

src/core/ext/client_channel/client_channel_plugin.c

@@ -43,6 +43,7 @@
 #include "src/core/ext/client_channel/lb_policy_registry.h"
 #include "src/core/ext/client_channel/proxy_mapper_registry.h"
 #include "src/core/ext/client_channel/resolver_registry.h"
+#include "src/core/ext/client_channel/retry_throttle.h"
 #include "src/core/ext/client_channel/subchannel_index.h"
 #include "src/core/lib/surface/channel_init.h"
 
@@ -82,6 +83,7 @@ static bool set_default_host_if_unset(grpc_exec_ctx *exec_ctx,
 void grpc_client_channel_init(void) {
   grpc_lb_policy_registry_init();
   grpc_resolver_registry_init();
+  grpc_retry_throttle_map_init();
   grpc_proxy_mapper_registry_init();
   grpc_register_http_proxy_mapper();
   grpc_subchannel_index_init();
@@ -96,6 +98,7 @@ void grpc_client_channel_shutdown(void) {
   grpc_subchannel_index_shutdown();
   grpc_channel_init_shutdown();
   grpc_proxy_mapper_registry_shutdown();
+  grpc_retry_throttle_map_shutdown();
   grpc_resolver_registry_shutdown();
   grpc_lb_policy_registry_shutdown();
 }

src/core/ext/client_channel/retry_throttle.c

@@ -0,0 +1,210 @@
+/*
+ *
+ * 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/client_channel/retry_throttle.h"
+
+#include <limits.h>
+#include <string.h>
+
+#include <grpc/support/alloc.h>
+#include <grpc/support/atm.h>
+#include <grpc/support/avl.h>
+#include <grpc/support/string_util.h>
+#include <grpc/support/sync.h>
+
+//
+// server_retry_throttle_data
+//
+
+struct grpc_server_retry_throttle_data {
+  gpr_refcount refs;
+  int max_milli_tokens;
+  int milli_token_ratio;
+  gpr_atm milli_tokens;
+  // A pointer to the replacement for this grpc_server_retry_throttle_data
+  // entry.  If non-NULL, then this entry is stale and must not be used.
+  // We hold a reference to the replacement.
+  gpr_atm replacement;
+};
+
+static void get_replacement_throttle_data_if_needed(
+    grpc_server_retry_throttle_data** throttle_data) {
+  while (true) {
+    grpc_server_retry_throttle_data* new_throttle_data =
+        (grpc_server_retry_throttle_data*)gpr_atm_acq_load(
+            &(*throttle_data)->replacement);
+    if (new_throttle_data == NULL) return;
+    *throttle_data = new_throttle_data;
+  }
+}
+
+bool grpc_server_retry_throttle_data_record_failure(
+    grpc_server_retry_throttle_data* throttle_data) {
+  // First, check if we are stale and need to be replaced.
+  get_replacement_throttle_data_if_needed(&throttle_data);
+  // We decrement milli_tokens by 1000 (1 token) for each failure.
+  const int new_value = (int)gpr_atm_no_barrier_clamped_add(
+      &throttle_data->milli_tokens, (gpr_atm)-1000, (gpr_atm)0,
+      (gpr_atm)throttle_data->max_milli_tokens);
+  // Retries are allowed as long as the new value is above the threshold
+  // (max_milli_tokens / 2).
+  return new_value > throttle_data->max_milli_tokens / 2;
+}
+
+void grpc_server_retry_throttle_data_record_success(
+    grpc_server_retry_throttle_data* throttle_data) {
+  // First, check if we are stale and need to be replaced.
+  get_replacement_throttle_data_if_needed(&throttle_data);
+  // We increment milli_tokens by milli_token_ratio for each success.
+  gpr_atm_no_barrier_clamped_add(
+      &throttle_data->milli_tokens, (gpr_atm)throttle_data->milli_token_ratio,
+      (gpr_atm)0, (gpr_atm)throttle_data->max_milli_tokens);
+}
+
+grpc_server_retry_throttle_data* grpc_server_retry_throttle_data_ref(
+    grpc_server_retry_throttle_data* throttle_data) {
+  gpr_ref(&throttle_data->refs);
+  return throttle_data;
+}
+
+void grpc_server_retry_throttle_data_unref(
+    grpc_server_retry_throttle_data* throttle_data) {
+  if (gpr_unref(&throttle_data->refs)) {
+    grpc_server_retry_throttle_data* replacement =
+        (grpc_server_retry_throttle_data*)gpr_atm_acq_load(
+            &throttle_data->replacement);
+    if (replacement != NULL) {
+      grpc_server_retry_throttle_data_unref(replacement);
+    }
+    gpr_free(throttle_data);
+  }
+}
+
+static grpc_server_retry_throttle_data* grpc_server_retry_throttle_data_create(
+    int max_milli_tokens, int milli_token_ratio,
+    grpc_server_retry_throttle_data* old_throttle_data) {
+  grpc_server_retry_throttle_data* throttle_data =
+      gpr_malloc(sizeof(*throttle_data));
+  memset(throttle_data, 0, sizeof(*throttle_data));
+  gpr_ref_init(&throttle_data->refs, 1);
+  throttle_data->max_milli_tokens = max_milli_tokens;
+  throttle_data->milli_token_ratio = milli_token_ratio;
+  int initial_milli_tokens = max_milli_tokens;
+  // If there was a pre-existing entry for this server name, initialize
+  // the token count by scaling proportionately to the old data.  This
+  // ensures that if we're already throttling retries on the old scale,
+  // we will start out doing the same thing on the new one.
+  if (old_throttle_data != NULL) {
+    double token_fraction =
+        (int)gpr_atm_acq_load(&old_throttle_data->milli_tokens) /
+        (double)old_throttle_data->max_milli_tokens;
+    initial_milli_tokens = (int)(token_fraction * max_milli_tokens);
+  }
+  gpr_atm_rel_store(&throttle_data->milli_tokens,
+                    (gpr_atm)initial_milli_tokens);
+  // If there was a pre-existing entry, mark it as stale and give it a
+  // pointer to the new entry, which is its replacement.
+  if (old_throttle_data != NULL) {
+    grpc_server_retry_throttle_data_ref(throttle_data);
+    gpr_atm_rel_store(&old_throttle_data->replacement, (gpr_atm)throttle_data);
+  }
+  return throttle_data;
+}
+
+//
+// avl vtable for string -> server_retry_throttle_data map
+//
+
+static void* copy_server_name(void* key) { return gpr_strdup(key); }
+
+static long compare_server_name(void* key1, void* key2) {
+  return strcmp(key1, key2);
+}
+
+static void destroy_server_retry_throttle_data(void* value) {
+  grpc_server_retry_throttle_data* throttle_data = value;
+  grpc_server_retry_throttle_data_unref(throttle_data);
+}
+
+static void* copy_server_retry_throttle_data(void* value) {
+  grpc_server_retry_throttle_data* throttle_data = value;
+  return grpc_server_retry_throttle_data_ref(throttle_data);
+}
+
+static const gpr_avl_vtable avl_vtable = {
+    gpr_free /* destroy_key */, copy_server_name, compare_server_name,
+    destroy_server_retry_throttle_data, copy_server_retry_throttle_data};
+
+//
+// server_retry_throttle_map
+//
+
+static gpr_mu g_mu;
+static gpr_avl g_avl;
+
+void grpc_retry_throttle_map_init() {
+  gpr_mu_init(&g_mu);
+  g_avl = gpr_avl_create(&avl_vtable);
+}
+
+void grpc_retry_throttle_map_shutdown() {
+  gpr_mu_destroy(&g_mu);
+  gpr_avl_unref(g_avl);
+}
+
+grpc_server_retry_throttle_data* grpc_retry_throttle_map_get_data_for_server(
+    const char* server_name, int max_milli_tokens, int milli_token_ratio) {
+  gpr_mu_lock(&g_mu);
+  grpc_server_retry_throttle_data* throttle_data =
+      gpr_avl_get(g_avl, (char*)server_name);
+  if (throttle_data == NULL) {
+    // Entry not found.  Create a new one.
+    throttle_data = grpc_server_retry_throttle_data_create(
+        max_milli_tokens, milli_token_ratio, NULL);
+    g_avl = gpr_avl_add(g_avl, (char*)server_name, throttle_data);
+  } else {
+    if (throttle_data->max_milli_tokens != max_milli_tokens ||
+        throttle_data->milli_token_ratio != milli_token_ratio) {
+      // Entry found but with old parameters.  Create a new one based on
+      // the original one.
+      throttle_data = grpc_server_retry_throttle_data_create(
+          max_milli_tokens, milli_token_ratio, throttle_data);
+      g_avl = gpr_avl_add(g_avl, (char*)server_name, throttle_data);
+    } else {
+      // Entry found.  Increase refcount.
+      grpc_server_retry_throttle_data_ref(throttle_data);
+    }
+  }
+  gpr_mu_unlock(&g_mu);
+  return throttle_data;
+}

src/core/ext/client_channel/retry_throttle.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_CLIENT_CHANNEL_RETRY_THROTTLE_H
+#define GRPC_CORE_EXT_CLIENT_CHANNEL_RETRY_THROTTLE_H
+
+#include <stdbool.h>
+
+/// Tracks retry throttling data for an individual server name.
+typedef struct grpc_server_retry_throttle_data grpc_server_retry_throttle_data;
+
+/// Records a failure.  Returns true if it's okay to send a retry.
+bool grpc_server_retry_throttle_data_record_failure(
+    grpc_server_retry_throttle_data* throttle_data);
+/// Records a success.
+void grpc_server_retry_throttle_data_record_success(
+    grpc_server_retry_throttle_data* throttle_data);
+
+grpc_server_retry_throttle_data* grpc_server_retry_throttle_data_ref(
+    grpc_server_retry_throttle_data* throttle_data);
+void grpc_server_retry_throttle_data_unref(
+    grpc_server_retry_throttle_data* throttle_data);
+
+/// Initializes global map of failure data for each server name.
+void grpc_retry_throttle_map_init();
+/// Shuts down global map of failure data for each server name.
+void grpc_retry_throttle_map_shutdown();
+
+/// Returns a reference to the failure data for \a server_name, creating
+/// a new entry if needed.
+/// Caller must eventually unref via \a grpc_server_retry_throttle_data_unref().
+grpc_server_retry_throttle_data* grpc_retry_throttle_map_get_data_for_server(
+    const char* server_name, int max_milli_tokens, int milli_token_ratio);
+
+#endif /* GRPC_CORE_EXT_CLIENT_CHANNEL_RETRY_THROTTLE_H */

src/core/lib/support/atm.c

@@ -0,0 +1,47 @@
+/*
+ *
+ * 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 <grpc/support/atm.h>
+#include <grpc/support/useful.h>
+
+gpr_atm gpr_atm_no_barrier_clamped_add(gpr_atm *value, gpr_atm delta,
+                                       gpr_atm min, gpr_atm max) {
+  gpr_atm current;
+  gpr_atm new;
+  do {
+    current = gpr_atm_no_barrier_load(value);
+    new = GPR_CLAMP(current + delta, min, max);
+    if (new == current) break;
+  } while (!gpr_atm_no_barrier_cas(value, current, new));
+  return new;
+}

src/core/lib/transport/service_config.c

@@ -93,6 +93,18 @@ void grpc_service_config_destroy(grpc_service_config* service_config) {
   gpr_free(service_config);
 }
 
+void grpc_service_config_parse_global_params(
+    const grpc_service_config* service_config,
+    void (*process_json)(const grpc_json* json, void* arg), void* arg) {
+  const grpc_json* json = service_config->json_tree;
+  if (json->type != GRPC_JSON_OBJECT || json->key != NULL) return;
+  for (grpc_json* field = json->child; field != NULL; field = field->next) {
+    if (field->key == NULL) return;
+    if (strcmp(field->key, "methodConfig") == 0) continue;
+    process_json(field, arg);
+  }
+}
+
 const char* grpc_service_config_get_lb_policy_name(
     const grpc_service_config* service_config) {
   const grpc_json* json = service_config->json_tree;

src/core/lib/transport/service_config.h

@@ -42,6 +42,12 @@ typedef struct grpc_service_config grpc_service_config;
 grpc_service_config* grpc_service_config_create(const char* json_string);
 void grpc_service_config_destroy(grpc_service_config* service_config);
 
+/// Invokes \a process_json() for each global parameter in the service
+/// config.  \a arg is passed as the second argument to \a process_json().
+void grpc_service_config_parse_global_params(
+    const grpc_service_config* service_config,
+    void (*process_json)(const grpc_json* json, void* arg), void* arg);
+
 /// Gets the LB policy name from \a service_config.
 /// Returns NULL if no LB policy name was specified.
 /// Caller does NOT take ownership.

src/python/grpcio/grpc_core_dependencies.py

@@ -34,6 +34,7 @@ CORE_SOURCE_FILES = [
   'src/core/lib/profiling/stap_timers.c',
   'src/core/lib/support/alloc.c',
   'src/core/lib/support/arena.c',
+  'src/core/lib/support/atm.c',
   'src/core/lib/support/avl.c',
   'src/core/lib/support/backoff.c',
   'src/core/lib/support/cmdline.c',
@@ -267,6 +268,7 @@ CORE_SOURCE_FILES = [
   'src/core/ext/client_channel/resolver.c',
   'src/core/ext/client_channel/resolver_factory.c',
   'src/core/ext/client_channel/resolver_registry.c',
+  'src/core/ext/client_channel/retry_throttle.c',
   'src/core/ext/client_channel/subchannel.c',
   'src/core/ext/client_channel/subchannel_index.c',
   'src/core/ext/client_channel/uri_parser.c',

tools/doxygen/Doxyfile.core.internal

@@ -929,6 +929,8 @@ src/core/ext/client_channel/resolver_factory.c \
 src/core/ext/client_channel/resolver_factory.h \
 src/core/ext/client_channel/resolver_registry.c \
 src/core/ext/client_channel/resolver_registry.h \
+src/core/ext/client_channel/retry_throttle.c \
+src/core/ext/client_channel/retry_throttle.h \
 src/core/ext/client_channel/subchannel.c \
 src/core/ext/client_channel/subchannel.h \
 src/core/ext/client_channel/subchannel_index.c \
@@ -1235,6 +1237,7 @@ src/core/lib/slice/slice_string_helpers.h \
 src/core/lib/support/alloc.c \
 src/core/lib/support/arena.c \
 src/core/lib/support/arena.h \
+src/core/lib/support/atm.c \
 src/core/lib/support/avl.c \
 src/core/lib/support/backoff.c \
 src/core/lib/support/backoff.h \

tools/run_tests/generated/sources_and_headers.json

@@ -7350,6 +7350,7 @@
       "src/core/lib/support/alloc.c", 
       "src/core/lib/support/arena.c", 
       "src/core/lib/support/arena.h", 
+      "src/core/lib/support/atm.c", 
       "src/core/lib/support/avl.c", 
       "src/core/lib/support/backoff.c", 
       "src/core/lib/support/backoff.h", 
@@ -7834,6 +7835,7 @@
       "src/core/ext/client_channel/resolver.h", 
       "src/core/ext/client_channel/resolver_factory.h", 
       "src/core/ext/client_channel/resolver_registry.h", 
+      "src/core/ext/client_channel/retry_throttle.h", 
       "src/core/ext/client_channel/subchannel.h", 
       "src/core/ext/client_channel/subchannel_index.h", 
       "src/core/ext/client_channel/uri_parser.h"
@@ -7875,6 +7877,8 @@
       "src/core/ext/client_channel/resolver_factory.h", 
       "src/core/ext/client_channel/resolver_registry.c", 
       "src/core/ext/client_channel/resolver_registry.h", 
+      "src/core/ext/client_channel/retry_throttle.c", 
+      "src/core/ext/client_channel/retry_throttle.h", 
       "src/core/ext/client_channel/subchannel.c", 
       "src/core/ext/client_channel/subchannel.h", 
       "src/core/ext/client_channel/subchannel_index.c", 

vsprojects/vcxproj/gpr/gpr.vcxproj

@@ -211,6 +211,8 @@
     </ClCompile>
     <ClCompile Include="$(SolutionDir)\..\src\core\lib\support\arena.c">
     </ClCompile>
+    <ClCompile Include="$(SolutionDir)\..\src\core\lib\support\atm.c">
+    </ClCompile>
     <ClCompile Include="$(SolutionDir)\..\src\core\lib\support\avl.c">
     </ClCompile>
     <ClCompile Include="$(SolutionDir)\..\src\core\lib\support\backoff.c">

vsprojects/vcxproj/gpr/gpr.vcxproj.filters

@@ -13,6 +13,9 @@
     <ClCompile Include="$(SolutionDir)\..\src\core\lib\support\arena.c">
       <Filter>src\core\lib\support</Filter>
     </ClCompile>
+    <ClCompile Include="$(SolutionDir)\..\src\core\lib\support\atm.c">
+      <Filter>src\core\lib\support</Filter>
+    </ClCompile>
     <ClCompile Include="$(SolutionDir)\..\src\core\lib\support\avl.c">
       <Filter>src\core\lib\support</Filter>
     </ClCompile>

vsprojects/vcxproj/grpc/grpc.vcxproj

@@ -467,6 +467,7 @@
     <ClInclude Include="$(SolutionDir)\..\src\core\ext\client_channel\resolver.h" />
     <ClInclude Include="$(SolutionDir)\..\src\core\ext\client_channel\resolver_factory.h" />
     <ClInclude Include="$(SolutionDir)\..\src\core\ext\client_channel\resolver_registry.h" />
+    <ClInclude Include="$(SolutionDir)\..\src\core\ext\client_channel\retry_throttle.h" />
     <ClInclude Include="$(SolutionDir)\..\src\core\ext\client_channel\subchannel.h" />
     <ClInclude Include="$(SolutionDir)\..\src\core\ext\client_channel\subchannel_index.h" />
     <ClInclude Include="$(SolutionDir)\..\src\core\ext\client_channel\uri_parser.h" />
@@ -883,6 +884,8 @@
     </ClCompile>
     <ClCompile Include="$(SolutionDir)\..\src\core\ext\client_channel\resolver_registry.c">
     </ClCompile>
+    <ClCompile Include="$(SolutionDir)\..\src\core\ext\client_channel\retry_throttle.c">
+    </ClCompile>
     <ClCompile Include="$(SolutionDir)\..\src\core\ext\client_channel\subchannel.c">
     </ClCompile>
     <ClCompile Include="$(SolutionDir)\..\src\core\ext\client_channel\subchannel_index.c">

vsprojects/vcxproj/grpc/grpc.vcxproj.filters

@@ -577,6 +577,9 @@
     <ClCompile Include="$(SolutionDir)\..\src\core\ext\client_channel\resolver_registry.c">
       <Filter>src\core\ext\client_channel</Filter>
     </ClCompile>
+    <ClCompile Include="$(SolutionDir)\..\src\core\ext\client_channel\retry_throttle.c">
+      <Filter>src\core\ext\client_channel</Filter>
+    </ClCompile>
     <ClCompile Include="$(SolutionDir)\..\src\core\ext\client_channel\subchannel.c">
       <Filter>src\core\ext\client_channel</Filter>
     </ClCompile>
@@ -1283,6 +1286,9 @@
     <ClInclude Include="$(SolutionDir)\..\src\core\ext\client_channel\resolver_registry.h">
       <Filter>src\core\ext\client_channel</Filter>
     </ClInclude>
+    <ClInclude Include="$(SolutionDir)\..\src\core\ext\client_channel\retry_throttle.h">
+      <Filter>src\core\ext\client_channel</Filter>
+    </ClInclude>
     <ClInclude Include="$(SolutionDir)\..\src\core\ext\client_channel\subchannel.h">
       <Filter>src\core\ext\client_channel</Filter>
     </ClInclude>

vsprojects/vcxproj/grpc_unsecure/grpc_unsecure.vcxproj

@@ -433,6 +433,7 @@
     <ClInclude Include="$(SolutionDir)\..\src\core\ext\client_channel\resolver.h" />
     <ClInclude Include="$(SolutionDir)\..\src\core\ext\client_channel\resolver_factory.h" />
     <ClInclude Include="$(SolutionDir)\..\src\core\ext\client_channel\resolver_registry.h" />
+    <ClInclude Include="$(SolutionDir)\..\src\core\ext\client_channel\retry_throttle.h" />
     <ClInclude Include="$(SolutionDir)\..\src\core\ext\client_channel\subchannel.h" />
     <ClInclude Include="$(SolutionDir)\..\src\core\ext\client_channel\subchannel_index.h" />
     <ClInclude Include="$(SolutionDir)\..\src\core\ext\client_channel\uri_parser.h" />
@@ -800,6 +801,8 @@
     </ClCompile>
     <ClCompile Include="$(SolutionDir)\..\src\core\ext\client_channel\resolver_registry.c">
     </ClCompile>
+    <ClCompile Include="$(SolutionDir)\..\src\core\ext\client_channel\retry_throttle.c">
+    </ClCompile>
     <ClCompile Include="$(SolutionDir)\..\src\core\ext\client_channel\subchannel.c">
     </ClCompile>
     <ClCompile Include="$(SolutionDir)\..\src\core\ext\client_channel\subchannel_index.c">

vsprojects/vcxproj/grpc_unsecure/grpc_unsecure.vcxproj.filters

@@ -505,6 +505,9 @@
     <ClCompile Include="$(SolutionDir)\..\src\core\ext\client_channel\resolver_registry.c">
       <Filter>src\core\ext\client_channel</Filter>
     </ClCompile>
+    <ClCompile Include="$(SolutionDir)\..\src\core\ext\client_channel\retry_throttle.c">
+      <Filter>src\core\ext\client_channel</Filter>
+    </ClCompile>
     <ClCompile Include="$(SolutionDir)\..\src\core\ext\client_channel\subchannel.c">
       <Filter>src\core\ext\client_channel</Filter>
     </ClCompile>
@@ -1121,6 +1124,9 @@
     <ClInclude Include="$(SolutionDir)\..\src\core\ext\client_channel\resolver_registry.h">
       <Filter>src\core\ext\client_channel</Filter>
     </ClInclude>
+    <ClInclude Include="$(SolutionDir)\..\src\core\ext\client_channel\retry_throttle.h">
+      <Filter>src\core\ext\client_channel</Filter>
+    </ClInclude>
     <ClInclude Include="$(SolutionDir)\..\src\core\ext\client_channel\subchannel.h">
       <Filter>src\core\ext\client_channel</Filter>
     </ClInclude>