Merge branch 'master' into cq_mpsc_based

.gitignore

@@ -118,3 +118,13 @@ gdb.txt
 
 # ctags file
 tags
+
+# perf data
+perf.data
+perf.data.old
+
+# bm_diff
+bm_diff_new/
+bm_diff_old/
+bm_*.json
+

CMakeLists.txt

@@ -391,6 +391,7 @@ add_dependencies(buildtests_c error_test)
 if(_gRPC_PLATFORM_LINUX)
 add_dependencies(buildtests_c ev_epoll_linux_test)
 endif()
+add_dependencies(buildtests_c fake_resolver_test)
 if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_MAC OR _gRPC_PLATFORM_POSIX)
 add_dependencies(buildtests_c fd_conservation_posix_test)
 endif()
@@ -5444,6 +5445,37 @@ target_link_libraries(ev_epoll_linux_test
 )
 
 endif()
+endif (gRPC_BUILD_TESTS)
+if (gRPC_BUILD_TESTS)
+
+add_executable(fake_resolver_test
+  test/core/client_channel/resolvers/fake_resolver_test.c
+)
+
+
+target_include_directories(fake_resolver_test
+  PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}
+  PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}/include
+  PRIVATE ${BORINGSSL_ROOT_DIR}/include
+  PRIVATE ${PROTOBUF_ROOT_DIR}/src
+  PRIVATE ${BENCHMARK_ROOT_DIR}/include
+  PRIVATE ${ZLIB_ROOT_DIR}
+  PRIVATE ${CMAKE_CURRENT_BINARY_DIR}/third_party/zlib
+  PRIVATE ${CARES_BUILD_INCLUDE_DIR}
+  PRIVATE ${CARES_INCLUDE_DIR}
+  PRIVATE ${CARES_PLATFORM_INCLUDE_DIR}
+  PRIVATE ${CMAKE_CURRENT_BINARY_DIR}/third_party/cares/cares
+  PRIVATE ${CMAKE_CURRENT_BINARY_DIR}/third_party/gflags/include
+)
+
+target_link_libraries(fake_resolver_test
+  ${_gRPC_ALLTARGETS_LIBRARIES}
+  grpc_test_util
+  grpc
+  gpr_test_util
+  gpr
+)
+
 endif (gRPC_BUILD_TESTS)
 if (gRPC_BUILD_TESTS)
 if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_MAC OR _gRPC_PLATFORM_POSIX)

Makefile

@@ -981,6 +981,7 @@ dualstack_socket_test: $(BINDIR)/$(CONFIG)/dualstack_socket_test
 endpoint_pair_test: $(BINDIR)/$(CONFIG)/endpoint_pair_test
 error_test: $(BINDIR)/$(CONFIG)/error_test
 ev_epoll_linux_test: $(BINDIR)/$(CONFIG)/ev_epoll_linux_test
+fake_resolver_test: $(BINDIR)/$(CONFIG)/fake_resolver_test
 fd_conservation_posix_test: $(BINDIR)/$(CONFIG)/fd_conservation_posix_test
 fd_posix_test: $(BINDIR)/$(CONFIG)/fd_posix_test
 fling_client: $(BINDIR)/$(CONFIG)/fling_client
@@ -1366,6 +1367,7 @@ buildtests_c: privatelibs_c \
   $(BINDIR)/$(CONFIG)/endpoint_pair_test \
   $(BINDIR)/$(CONFIG)/error_test \
   $(BINDIR)/$(CONFIG)/ev_epoll_linux_test \
+  $(BINDIR)/$(CONFIG)/fake_resolver_test \
   $(BINDIR)/$(CONFIG)/fd_conservation_posix_test \
   $(BINDIR)/$(CONFIG)/fd_posix_test \
   $(BINDIR)/$(CONFIG)/fling_client \
@@ -1777,6 +1779,8 @@ test_c: buildtests_c
 	$(Q) $(BINDIR)/$(CONFIG)/error_test || ( echo test error_test failed ; exit 1 )
 	$(E) "[RUN]     Testing ev_epoll_linux_test"
 	$(Q) $(BINDIR)/$(CONFIG)/ev_epoll_linux_test || ( echo test ev_epoll_linux_test failed ; exit 1 )
+	$(E) "[RUN]     Testing fake_resolver_test"
+	$(Q) $(BINDIR)/$(CONFIG)/fake_resolver_test || ( echo test fake_resolver_test failed ; exit 1 )
 	$(E) "[RUN]     Testing fd_conservation_posix_test"
 	$(Q) $(BINDIR)/$(CONFIG)/fd_conservation_posix_test || ( echo test fd_conservation_posix_test failed ; exit 1 )
 	$(E) "[RUN]     Testing fd_posix_test"
@@ -9401,6 +9405,38 @@ endif
 endif
 
 
+FAKE_RESOLVER_TEST_SRC = \
+    test/core/client_channel/resolvers/fake_resolver_test.c \
+
+FAKE_RESOLVER_TEST_OBJS = $(addprefix $(OBJDIR)/$(CONFIG)/, $(addsuffix .o, $(basename $(FAKE_RESOLVER_TEST_SRC))))
+ifeq ($(NO_SECURE),true)
+
+# You can't build secure targets if you don't have OpenSSL.
+
+$(BINDIR)/$(CONFIG)/fake_resolver_test: openssl_dep_error
+
+else
+
+
+
+$(BINDIR)/$(CONFIG)/fake_resolver_test: $(FAKE_RESOLVER_TEST_OBJS) $(LIBDIR)/$(CONFIG)/libgrpc_test_util.a $(LIBDIR)/$(CONFIG)/libgrpc.a $(LIBDIR)/$(CONFIG)/libgpr_test_util.a $(LIBDIR)/$(CONFIG)/libgpr.a
+	$(E) "[LD]      Linking $@"
+	$(Q) mkdir -p `dirname $@`
+	$(Q) $(LD) $(LDFLAGS) $(FAKE_RESOLVER_TEST_OBJS) $(LIBDIR)/$(CONFIG)/libgrpc_test_util.a $(LIBDIR)/$(CONFIG)/libgrpc.a $(LIBDIR)/$(CONFIG)/libgpr_test_util.a $(LIBDIR)/$(CONFIG)/libgpr.a $(LDLIBS) $(LDLIBS_SECURE) -o $(BINDIR)/$(CONFIG)/fake_resolver_test
+
+endif
+
+$(OBJDIR)/$(CONFIG)/test/core/client_channel/resolvers/fake_resolver_test.o:  $(LIBDIR)/$(CONFIG)/libgrpc_test_util.a $(LIBDIR)/$(CONFIG)/libgrpc.a $(LIBDIR)/$(CONFIG)/libgpr_test_util.a $(LIBDIR)/$(CONFIG)/libgpr.a
+
+deps_fake_resolver_test: $(FAKE_RESOLVER_TEST_OBJS:.o=.dep)
+
+ifneq ($(NO_SECURE),true)
+ifneq ($(NO_DEPS),true)
+-include $(FAKE_RESOLVER_TEST_OBJS:.o=.dep)
+endif
+endif
+
+
 FD_CONSERVATION_POSIX_TEST_SRC = \
     test/core/iomgr/fd_conservation_posix_test.c \
 

PYTHON-MANIFEST.in

@@ -7,7 +7,7 @@ graft include/grpc
 graft third_party/boringssl
 graft third_party/nanopb
 graft third_party/zlib
-graft third_party/c-ares
+graft third_party/cares
 include src/python/grpcio/_spawn_patch.py
 include src/python/grpcio/commands.py
 include src/python/grpcio/grpc_version.py

build.yaml

@@ -1820,6 +1820,16 @@ targets:
   - uv
   platforms:
   - linux
+- name: fake_resolver_test
+  build: test
+  language: c
+  src:
+  - test/core/client_channel/resolvers/fake_resolver_test.c
+  deps:
+  - grpc_test_util
+  - grpc
+  - gpr_test_util
+  - gpr
 - name: fd_conservation_posix_test
   build: test
   language: c

doc/server_side_auth.md

@@ -13,7 +13,7 @@ The contents of the *auth properties* are populated by an *auth interceptor*. Th
 
 WARNING: AuthContext is the only reliable source of truth when it comes to authenticating RPCs. Using any other call/context properties for authentication purposes is wrong and inherently unsafe.
 
-####Example AuthContext contents
+#### Example AuthContext contents
 
 For secure channel using mutual TLS authentication with both client and server certificates (test certificates from this repository are used).
 
@@ -45,7 +45,7 @@ gRPC comes with some basic "interceptors" already built-in.
 WARNING: While there is a public API that allows anyone to write their own custom interceptor, please think twice before using it.
 There are legitimate uses for custom interceptors but you should keep in mind that as auth interceptors essentially decide which RPCs are authenticated and which are not, their code is very sensitive from the security perspective and getting things wrong might have serious consequences. If unsure, we strongly recommend to rely on official & proven interceptors that come with gRPC.
 
-####Available auth interceptors
+#### Available auth interceptors
 - TLS/SSL certificate authentication (built into gRPC's security layer, automatically used whenever you use a secure connection)
 - (coming soon) JWT auth token authentication
 - more will be added over time

examples/cpp/README.md

@@ -1,4 +1,4 @@
-#gRPC in 3 minutes (C++)
+# gRPC in 3 minutes (C++)
 
 ## Installation
 

examples/cpp/cpptutorial.md

@@ -1,4 +1,4 @@
-#gRPC Basics: C++
+# gRPC Basics: C++
 
 This tutorial provides a basic C++ programmer's introduction to working with
 gRPC. By walking through this example you'll learn how to:

examples/csharp/route_guide/README.md

@@ -1,4 +1,4 @@
-#gRPC Basics: C# sample code
+# gRPC Basics: C# sample code
 
 The files in this folder are the samples used in [gRPC Basics: C#][],
 a detailed tutorial for using gRPC in C#.

examples/node/dynamic_codegen/route_guide/README.md

@@ -1,4 +1,4 @@
-#gRPC Basics: Node.js sample code
+# gRPC Basics: Node.js sample code
 
 The files in this folder are the samples used in [gRPC Basics: Node.js][], a detailed tutorial for using gRPC in Node.js.
 

examples/node/static_codegen/route_guide/README.md

@@ -1,4 +1,4 @@
-#gRPC Basics: Node.js sample code
+# gRPC Basics: Node.js sample code
 
 The files in this folder are the samples used in [gRPC Basics: Node.js][], a detailed tutorial for using gRPC in Node.js.
 

examples/objective-c/auth_sample/README.md

@@ -1,3 +1,3 @@
-#OAuth2 on gRPC: Objective-C
+# OAuth2 on gRPC: Objective-C
 
 This is the supporting code for the tutorial "[OAuth2 on gRPC: Objective-C](http://www.grpc.io/docs/tutorials/auth/oauth2-objective-c.html)."

examples/objective-c/helloworld/README.md

@@ -1,4 +1,4 @@
-#gRPC in 3 minutes (Objective-C)
+# gRPC in 3 minutes (Objective-C)
 
 ## Installation
 

examples/objective-c/route_guide/README.md

@@ -1,4 +1,4 @@
-#gRPC Basics: Objective-C
+# gRPC Basics: Objective-C
 
 This is the supporting code for the tutorial "[gRPC Basics: Objective-C](http://www.grpc.io/docs/tutorials/basic/objective-c.html)."
 

examples/php/route_guide/README.md

@@ -1,4 +1,4 @@
-#gRPC Basics: PHP sample code
+# gRPC Basics: PHP sample code
 
 The files in this folder are the samples used in [gRPC Basics: PHP][],
 a detailed tutorial for using gRPC in PHP.

examples/ruby/errors_and_cancellation/README.md

@@ -1,4 +1,4 @@
-#Errors and Cancelletion code samples for grpc-ruby
+# Errors and Cancelletion code samples for grpc-ruby
 
 The examples in this directory show use of grpc errors.
 

examples/ruby/route_guide/README.md

@@ -1,4 +1,4 @@
-#gRPC Basics: Ruby sample code
+# gRPC Basics: Ruby sample code
 
 The files in this folder are the samples used in [gRPC Basics: Ruby][],
 a detailed tutorial for using gRPC in Ruby.

grpc.def

@@ -72,7 +72,6 @@ EXPORTS
     grpc_channel_create_registered_call
     grpc_call_start_batch
     grpc_call_get_peer
-    grpc_call_set_load_reporting_cost_context
     grpc_census_call_set_context
     grpc_census_call_get_context
     grpc_channel_get_target

include/grpc++/impl/codegen/server_interface.h

@@ -122,9 +122,7 @@ class ServerInterface : public CallHook {
   /// caller is required to keep all completion queues live until the server is
   /// destroyed.
   /// \param num_cqs How many completion queues does \a cqs hold.
-  ///
-  /// \return true on a successful shutdown.
-  virtual bool Start(ServerCompletionQueue** cqs, size_t num_cqs) = 0;
+  virtual void Start(ServerCompletionQueue** cqs, size_t num_cqs) = 0;
 
   virtual void ShutdownInternal(gpr_timespec deadline) = 0;
 

include/grpc++/server.h

@@ -89,7 +89,8 @@ class Server final : public ServerInterface, private GrpcLibraryCodegen {
     /// Called before server is started.
     virtual void PreServerStart(Server* server) {}
     /// Called after a server port is added.
-    virtual void AddPort(Server* server, int port) {}
+    virtual void AddPort(Server* server, const grpc::string& addr,
+                         ServerCredentials* creds, int port) {}
   };
   /// Set the global callback object. Can only be called once. Does not take
   /// ownership of callbacks, and expects the pointed to object to be alive
@@ -177,9 +178,7 @@ class Server final : public ServerInterface, private GrpcLibraryCodegen {
   /// caller is required to keep all completion queues live until the server is
   /// destroyed.
   /// \param num_cqs How many completion queues does \a cqs hold.
-  ///
-  /// \return true on a successful shutdown.
-  bool Start(ServerCompletionQueue** cqs, size_t num_cqs) override;
+  void Start(ServerCompletionQueue** cqs, size_t num_cqs) override;
 
   void PerformOpsOnCall(CallOpSetInterface* ops, Call* call) override;
 

include/grpc/grpc.h

@@ -296,12 +296,6 @@ GRPCAPI grpc_call_error grpc_call_start_batch(grpc_call *call,
     functionality. Instead, use grpc_auth_context. */
 GRPCAPI char *grpc_call_get_peer(grpc_call *call);
 
-struct grpc_load_reporting_cost_context;
-
-/* Associate costs contained in \a cost_context to \a call. */
-GRPCAPI void grpc_call_set_load_reporting_cost_context(
-    grpc_call *call, struct grpc_load_reporting_cost_context *context);
-
 struct census_context;
 
 /** Set census context for a call; Must be called before first call to

include/grpc/impl/codegen/grpc_types.h

@@ -248,6 +248,8 @@ typedef struct {
 /** Secondary user agent: goes at the end of the user-agent metadata
     sent on each request. A string. */
 #define GRPC_ARG_SECONDARY_USER_AGENT_STRING "grpc.secondary_user_agent"
+/** The minimum time between subsequent connection attempts, in ms */
+#define GRPC_ARG_MIN_RECONNECT_BACKOFF_MS "grpc.min_reconnect_backoff_ms"
 /** The maximum time between subsequent connection attempts, in ms */
 #define GRPC_ARG_MAX_RECONNECT_BACKOFF_MS "grpc.max_reconnect_backoff_ms"
 /** The time between the first and second connection attempts, in ms */

include/grpc/load_reporting.h

@@ -35,7 +35,6 @@
 #define GRPC_LOAD_REPORTING_H
 
 #include <grpc/impl/codegen/port_platform.h>
-#include <grpc/slice.h>
 
 #ifdef __cplusplus
 extern "C" {
@@ -50,11 +49,12 @@ extern "C" {
  * gRPC LB system. */
 #define GRPC_LB_TOKEN_MD_KEY "lb-token"
 
-/** A sequence of values for load reporting purposes */
-typedef struct grpc_load_reporting_cost_context {
-  grpc_slice *values;
-  size_t values_count;
-} grpc_load_reporting_cost_context;
+/** Metadata key for gRPC LB cost reporting.
+ *
+ * The value corresponding to this key is an opaque binary blob reported by the
+ * backend as part of its trailing metadata containing cost information for the
+ * call. */
+#define GRPC_LB_COST_MD_KEY "lb-cost-bin"
 
 #ifdef __cplusplus
 }

include/grpc/slice.h

@@ -102,9 +102,9 @@ GPRAPI grpc_slice grpc_slice_from_static_string(const char *source);
 /* Create a slice pointing to constant memory */
 GPRAPI grpc_slice grpc_slice_from_static_buffer(const void *source, size_t len);
 
-/* Return a result slice derived from s, which shares a ref count with s, where
-   result.data==s.data+begin, and result.length==end-begin.
-   The ref count of s is increased by one.
+/* Return a result slice derived from s, which shares a ref count with \a s,
+   where result.data==s.data+begin, and result.length==end-begin. The ref count
+   of \a s is increased by one. Do not assign result back to \a s.
    Requires s initialized, begin <= end, begin <= s.length, and
    end <= source->length. */
 GPRAPI grpc_slice grpc_slice_sub(grpc_slice s, size_t begin, size_t end);

src/core/ext/filters/client_channel/client_channel.c

@@ -238,14 +238,23 @@ static void set_channel_connectivity_state_locked(grpc_exec_ctx *exec_ctx,
                                                   grpc_connectivity_state state,
                                                   grpc_error *error,
                                                   const char *reason) {
-  if ((state == GRPC_CHANNEL_TRANSIENT_FAILURE ||
-       state == GRPC_CHANNEL_SHUTDOWN) &&
-      chand->lb_policy != NULL) {
+  /* TODO: Improve failure handling:
+   * - Make it possible for policies to return GRPC_CHANNEL_TRANSIENT_FAILURE.
+   * - Hand over pending picks from old policies during the switch that happens
+   *   when resolver provides an update. */
+  if (chand->lb_policy != NULL) {
+    if (state == GRPC_CHANNEL_TRANSIENT_FAILURE) {
       /* cancel picks with wait_for_ready=false */
       grpc_lb_policy_cancel_picks_locked(
           exec_ctx, chand->lb_policy,
           /* mask= */ GRPC_INITIAL_METADATA_WAIT_FOR_READY,
           /* check= */ 0, GRPC_ERROR_REF(error));
+    } else if (state == GRPC_CHANNEL_SHUTDOWN) {
+      /* cancel all picks */
+      grpc_lb_policy_cancel_picks_locked(exec_ctx, chand->lb_policy,
+                                         /* mask= */ 0, /* check= */ 0,
+                                         GRPC_ERROR_REF(error));
+    }
   }
   grpc_connectivity_state_set(exec_ctx, &chand->state_tracker, state, error,
                               reason);
@@ -348,6 +357,33 @@ static void parse_retry_throttle_params(const grpc_json *field, void *arg) {
   }
 }
 
+// Wrap a closure associated with \a lb_policy. The associated callback (\a
+// wrapped_on_pick_closure_cb) is responsible for unref'ing \a lb_policy after
+// scheduling \a wrapped_closure.
+typedef struct wrapped_on_pick_closure_arg {
+  /* the closure instance using this struct as argument */
+  grpc_closure wrapper_closure;
+
+  /* the original closure. Usually a on_complete/notify cb for pick() and ping()
+   * calls against the internal RR instance, respectively. */
+  grpc_closure *wrapped_closure;
+
+  /* The policy instance related to the closure */
+  grpc_lb_policy *lb_policy;
+} wrapped_on_pick_closure_arg;
+
+// Invoke \a arg->wrapped_closure, unref \a arg->lb_policy and free \a arg.
+static void wrapped_on_pick_closure_cb(grpc_exec_ctx *exec_ctx, void *arg,
+                                       grpc_error *error) {
+  wrapped_on_pick_closure_arg *wc_arg = arg;
+  GPR_ASSERT(wc_arg != NULL);
+  GPR_ASSERT(wc_arg->wrapped_closure != NULL);
+  GPR_ASSERT(wc_arg->lb_policy != NULL);
+  grpc_closure_run(exec_ctx, wc_arg->wrapped_closure, GRPC_ERROR_REF(error));
+  GRPC_LB_POLICY_UNREF(exec_ctx, wc_arg->lb_policy, "pick_subchannel_wrapping");
+  gpr_free(wc_arg);
+}
+
 static void on_resolver_result_changed_locked(grpc_exec_ctx *exec_ctx,
                                               void *arg, grpc_error *error) {
   channel_data *chand = arg;
@@ -1037,11 +1073,29 @@ static bool pick_subchannel_locked(
     const grpc_lb_policy_pick_args inputs = {
         initial_metadata, initial_metadata_flags, &calld->lb_token_mdelem,
         gpr_inf_future(GPR_CLOCK_MONOTONIC)};
-    const bool result = grpc_lb_policy_pick_locked(
-        exec_ctx, lb_policy, &inputs, connected_subchannel, NULL, on_ready);
+
+    // Wrap the user-provided callback in order to hold a strong reference to
+    // the LB policy for the duration of the pick.
+    wrapped_on_pick_closure_arg *w_on_pick_arg =
+        gpr_zalloc(sizeof(*w_on_pick_arg));
+    grpc_closure_init(&w_on_pick_arg->wrapper_closure,
+                      wrapped_on_pick_closure_cb, w_on_pick_arg,
+                      grpc_schedule_on_exec_ctx);
+    w_on_pick_arg->wrapped_closure = on_ready;
+    GRPC_LB_POLICY_REF(lb_policy, "pick_subchannel_wrapping");
+    w_on_pick_arg->lb_policy = lb_policy;
+    const bool pick_done = grpc_lb_policy_pick_locked(
+        exec_ctx, lb_policy, &inputs, connected_subchannel, NULL,
+        &w_on_pick_arg->wrapper_closure);
+    if (pick_done) {
+      /* synchronous grpc_lb_policy_pick call. Unref the LB policy. */
+      GRPC_LB_POLICY_UNREF(exec_ctx, w_on_pick_arg->lb_policy,
+                           "pick_subchannel_wrapping");
+      gpr_free(w_on_pick_arg);
+    }
     GRPC_LB_POLICY_UNREF(exec_ctx, lb_policy, "pick_subchannel");
     GPR_TIMER_END("pick_subchannel", 0);
-    return result;
+    return pick_done;
   }
   if (chand->resolver != NULL && !chand->started_resolving) {
     chand->started_resolving = true;

src/core/ext/filters/client_channel/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.c

@@ -16,6 +16,12 @@ const pb_field_t grpc_lb_v1_Duration_fields[3] = {
     PB_LAST_FIELD
 };
 
+const pb_field_t grpc_lb_v1_Timestamp_fields[3] = {
+    PB_FIELD(  1, INT64   , OPTIONAL, STATIC  , FIRST, grpc_lb_v1_Timestamp, seconds, seconds, 0),
+    PB_FIELD(  2, INT32   , OPTIONAL, STATIC  , OTHER, grpc_lb_v1_Timestamp, nanos, seconds, 0),
+    PB_LAST_FIELD
+};
+
 const pb_field_t grpc_lb_v1_LoadBalanceRequest_fields[3] = {
     PB_FIELD(  1, MESSAGE , OPTIONAL, STATIC  , FIRST, grpc_lb_v1_LoadBalanceRequest, initial_request, initial_request, &grpc_lb_v1_InitialLoadBalanceRequest_fields),
     PB_FIELD(  2, MESSAGE , OPTIONAL, STATIC  , OTHER, grpc_lb_v1_LoadBalanceRequest, client_stats, initial_request, &grpc_lb_v1_ClientStats_fields),
@@ -27,10 +33,14 @@ const pb_field_t grpc_lb_v1_InitialLoadBalanceRequest_fields[2] = {
     PB_LAST_FIELD
 };
 
-const pb_field_t grpc_lb_v1_ClientStats_fields[4] = {
-    PB_FIELD(  1, INT64   , OPTIONAL, STATIC  , FIRST, grpc_lb_v1_ClientStats, total_requests, total_requests, 0),
-    PB_FIELD(  2, INT64   , OPTIONAL, STATIC  , OTHER, grpc_lb_v1_ClientStats, client_rpc_errors, total_requests, 0),
-    PB_FIELD(  3, INT64   , OPTIONAL, STATIC  , OTHER, grpc_lb_v1_ClientStats, dropped_requests, client_rpc_errors, 0),
+const pb_field_t grpc_lb_v1_ClientStats_fields[8] = {
+    PB_FIELD(  1, MESSAGE , OPTIONAL, STATIC  , FIRST, grpc_lb_v1_ClientStats, timestamp, timestamp, &grpc_lb_v1_Timestamp_fields),
+    PB_FIELD(  2, INT64   , OPTIONAL, STATIC  , OTHER, grpc_lb_v1_ClientStats, num_calls_started, timestamp, 0),
+    PB_FIELD(  3, INT64   , OPTIONAL, STATIC  , OTHER, grpc_lb_v1_ClientStats, num_calls_finished, num_calls_started, 0),
+    PB_FIELD(  4, INT64   , OPTIONAL, STATIC  , OTHER, grpc_lb_v1_ClientStats, num_calls_finished_with_drop_for_rate_limiting, num_calls_finished, 0),
+    PB_FIELD(  5, INT64   , OPTIONAL, STATIC  , OTHER, grpc_lb_v1_ClientStats, num_calls_finished_with_drop_for_load_balancing, num_calls_finished_with_drop_for_rate_limiting, 0),
+    PB_FIELD(  6, INT64   , OPTIONAL, STATIC  , OTHER, grpc_lb_v1_ClientStats, num_calls_finished_with_client_failed_to_send, num_calls_finished_with_drop_for_load_balancing, 0),
+    PB_FIELD(  7, INT64   , OPTIONAL, STATIC  , OTHER, grpc_lb_v1_ClientStats, num_calls_finished_known_received, num_calls_finished_with_client_failed_to_send, 0),
     PB_LAST_FIELD
 };
 
@@ -52,11 +62,12 @@ const pb_field_t grpc_lb_v1_ServerList_fields[3] = {
     PB_LAST_FIELD
 };
 
-const pb_field_t grpc_lb_v1_Server_fields[5] = {
+const pb_field_t grpc_lb_v1_Server_fields[6] = {
     PB_FIELD(  1, BYTES   , OPTIONAL, STATIC  , FIRST, grpc_lb_v1_Server, ip_address, ip_address, 0),
     PB_FIELD(  2, INT32   , OPTIONAL, STATIC  , OTHER, grpc_lb_v1_Server, port, ip_address, 0),
     PB_FIELD(  3, STRING  , OPTIONAL, STATIC  , OTHER, grpc_lb_v1_Server, load_balance_token, port, 0),
-    PB_FIELD(  4, BOOL    , OPTIONAL, STATIC  , OTHER, grpc_lb_v1_Server, drop_request, load_balance_token, 0),
+    PB_FIELD(  4, BOOL    , OPTIONAL, STATIC  , OTHER, grpc_lb_v1_Server, drop_for_rate_limiting, load_balance_token, 0),
+    PB_FIELD(  5, BOOL    , OPTIONAL, STATIC  , OTHER, grpc_lb_v1_Server, drop_for_load_balancing, drop_for_rate_limiting, 0),
     PB_LAST_FIELD
 };
 
@@ -70,7 +81,7 @@ const pb_field_t grpc_lb_v1_Server_fields[5] = {
  * numbers or field sizes that are larger than what can fit in 8 or 16 bit
  * field descriptors.
  */
-PB_STATIC_ASSERT((pb_membersize(grpc_lb_v1_LoadBalanceRequest, initial_request) < 65536 && pb_membersize(grpc_lb_v1_LoadBalanceRequest, client_stats) < 65536 && pb_membersize(grpc_lb_v1_LoadBalanceResponse, initial_response) < 65536 && pb_membersize(grpc_lb_v1_LoadBalanceResponse, server_list) < 65536 && pb_membersize(grpc_lb_v1_InitialLoadBalanceResponse, client_stats_report_interval) < 65536 && pb_membersize(grpc_lb_v1_ServerList, servers) < 65536 && pb_membersize(grpc_lb_v1_ServerList, expiration_interval) < 65536), YOU_MUST_DEFINE_PB_FIELD_32BIT_FOR_MESSAGES_grpc_lb_v1_Duration_grpc_lb_v1_LoadBalanceRequest_grpc_lb_v1_InitialLoadBalanceRequest_grpc_lb_v1_ClientStats_grpc_lb_v1_LoadBalanceResponse_grpc_lb_v1_InitialLoadBalanceResponse_grpc_lb_v1_ServerList_grpc_lb_v1_Server)
+PB_STATIC_ASSERT((pb_membersize(grpc_lb_v1_LoadBalanceRequest, initial_request) < 65536 && pb_membersize(grpc_lb_v1_LoadBalanceRequest, client_stats) < 65536 && pb_membersize(grpc_lb_v1_ClientStats, timestamp) < 65536 && pb_membersize(grpc_lb_v1_LoadBalanceResponse, initial_response) < 65536 && pb_membersize(grpc_lb_v1_LoadBalanceResponse, server_list) < 65536 && pb_membersize(grpc_lb_v1_InitialLoadBalanceResponse, client_stats_report_interval) < 65536 && pb_membersize(grpc_lb_v1_ServerList, servers) < 65536 && pb_membersize(grpc_lb_v1_ServerList, expiration_interval) < 65536), YOU_MUST_DEFINE_PB_FIELD_32BIT_FOR_MESSAGES_grpc_lb_v1_Duration_grpc_lb_v1_Timestamp_grpc_lb_v1_LoadBalanceRequest_grpc_lb_v1_InitialLoadBalanceRequest_grpc_lb_v1_ClientStats_grpc_lb_v1_LoadBalanceResponse_grpc_lb_v1_InitialLoadBalanceResponse_grpc_lb_v1_ServerList_grpc_lb_v1_Server)
 #endif
 
 #if !defined(PB_FIELD_16BIT) && !defined(PB_FIELD_32BIT)
@@ -81,7 +92,7 @@ PB_STATIC_ASSERT((pb_membersize(grpc_lb_v1_LoadBalanceRequest, initial_request)
  * numbers or field sizes that are larger than what can fit in the default
  * 8 bit descriptors.
  */
-PB_STATIC_ASSERT((pb_membersize(grpc_lb_v1_LoadBalanceRequest, initial_request) < 256 && pb_membersize(grpc_lb_v1_LoadBalanceRequest, client_stats) < 256 && pb_membersize(grpc_lb_v1_LoadBalanceResponse, initial_response) < 256 && pb_membersize(grpc_lb_v1_LoadBalanceResponse, server_list) < 256 && pb_membersize(grpc_lb_v1_InitialLoadBalanceResponse, client_stats_report_interval) < 256 && pb_membersize(grpc_lb_v1_ServerList, servers) < 256 && pb_membersize(grpc_lb_v1_ServerList, expiration_interval) < 256), YOU_MUST_DEFINE_PB_FIELD_16BIT_FOR_MESSAGES_grpc_lb_v1_Duration_grpc_lb_v1_LoadBalanceRequest_grpc_lb_v1_InitialLoadBalanceRequest_grpc_lb_v1_ClientStats_grpc_lb_v1_LoadBalanceResponse_grpc_lb_v1_InitialLoadBalanceResponse_grpc_lb_v1_ServerList_grpc_lb_v1_Server)
+PB_STATIC_ASSERT((pb_membersize(grpc_lb_v1_LoadBalanceRequest, initial_request) < 256 && pb_membersize(grpc_lb_v1_LoadBalanceRequest, client_stats) < 256 && pb_membersize(grpc_lb_v1_ClientStats, timestamp) < 256 && pb_membersize(grpc_lb_v1_LoadBalanceResponse, initial_response) < 256 && pb_membersize(grpc_lb_v1_LoadBalanceResponse, server_list) < 256 && pb_membersize(grpc_lb_v1_InitialLoadBalanceResponse, client_stats_report_interval) < 256 && pb_membersize(grpc_lb_v1_ServerList, servers) < 256 && pb_membersize(grpc_lb_v1_ServerList, expiration_interval) < 256), YOU_MUST_DEFINE_PB_FIELD_16BIT_FOR_MESSAGES_grpc_lb_v1_Duration_grpc_lb_v1_Timestamp_grpc_lb_v1_LoadBalanceRequest_grpc_lb_v1_InitialLoadBalanceRequest_grpc_lb_v1_ClientStats_grpc_lb_v1_LoadBalanceResponse_grpc_lb_v1_InitialLoadBalanceResponse_grpc_lb_v1_ServerList_grpc_lb_v1_Server)
 #endif
 
 

src/core/ext/filters/client_channel/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.h

@@ -14,16 +14,6 @@ extern "C" {
 #endif
 
 /* Struct definitions */
-typedef struct _grpc_lb_v1_ClientStats {
-    bool has_total_requests;
-    int64_t total_requests;
-    bool has_client_rpc_errors;
-    int64_t client_rpc_errors;
-    bool has_dropped_requests;
-    int64_t dropped_requests;
-/* @@protoc_insertion_point(struct:grpc_lb_v1_ClientStats) */
-} grpc_lb_v1_ClientStats;
-
 typedef struct _grpc_lb_v1_Duration {
     bool has_seconds;
     int64_t seconds;
@@ -46,11 +36,39 @@ typedef struct _grpc_lb_v1_Server {
     int32_t port;
     bool has_load_balance_token;
     char load_balance_token[50];
-    bool has_drop_request;
-    bool drop_request;
+    bool has_drop_for_rate_limiting;
+    bool drop_for_rate_limiting;
+    bool has_drop_for_load_balancing;
+    bool drop_for_load_balancing;
 /* @@protoc_insertion_point(struct:grpc_lb_v1_Server) */
 } grpc_lb_v1_Server;
 
+typedef struct _grpc_lb_v1_Timestamp {
+    bool has_seconds;
+    int64_t seconds;
+    bool has_nanos;
+    int32_t nanos;
+/* @@protoc_insertion_point(struct:grpc_lb_v1_Timestamp) */
+} grpc_lb_v1_Timestamp;
+
+typedef struct _grpc_lb_v1_ClientStats {
+    bool has_timestamp;
+    grpc_lb_v1_Timestamp timestamp;
+    bool has_num_calls_started;
+    int64_t num_calls_started;
+    bool has_num_calls_finished;
+    int64_t num_calls_finished;
+    bool has_num_calls_finished_with_drop_for_rate_limiting;
+    int64_t num_calls_finished_with_drop_for_rate_limiting;
+    bool has_num_calls_finished_with_drop_for_load_balancing;
+    int64_t num_calls_finished_with_drop_for_load_balancing;
+    bool has_num_calls_finished_with_client_failed_to_send;
+    int64_t num_calls_finished_with_client_failed_to_send;
+    bool has_num_calls_finished_known_received;
+    int64_t num_calls_finished_known_received;
+/* @@protoc_insertion_point(struct:grpc_lb_v1_ClientStats) */
+} grpc_lb_v1_ClientStats;
+
 typedef struct _grpc_lb_v1_InitialLoadBalanceResponse {
     bool has_load_balancer_delegate;
     char load_balancer_delegate[64];
@@ -59,6 +77,13 @@ typedef struct _grpc_lb_v1_InitialLoadBalanceResponse {
 /* @@protoc_insertion_point(struct:grpc_lb_v1_InitialLoadBalanceResponse) */
 } grpc_lb_v1_InitialLoadBalanceResponse;
 
+typedef struct _grpc_lb_v1_ServerList {
+    pb_callback_t servers;
+    bool has_expiration_interval;
+    grpc_lb_v1_Duration expiration_interval;
+/* @@protoc_insertion_point(struct:grpc_lb_v1_ServerList) */
+} grpc_lb_v1_ServerList;
+
 typedef struct _grpc_lb_v1_LoadBalanceRequest {
     bool has_initial_request;
     grpc_lb_v1_InitialLoadBalanceRequest initial_request;
@@ -67,13 +92,6 @@ typedef struct _grpc_lb_v1_LoadBalanceRequest {
 /* @@protoc_insertion_point(struct:grpc_lb_v1_LoadBalanceRequest) */
 } grpc_lb_v1_LoadBalanceRequest;
 
-typedef struct _grpc_lb_v1_ServerList {
-    pb_callback_t servers;
-    bool has_expiration_interval;
-    grpc_lb_v1_Duration expiration_interval;
-/* @@protoc_insertion_point(struct:grpc_lb_v1_ServerList) */
-} grpc_lb_v1_ServerList;
-
 typedef struct _grpc_lb_v1_LoadBalanceResponse {
     bool has_initial_response;
     grpc_lb_v1_InitialLoadBalanceResponse initial_response;
@@ -86,61 +104,72 @@ typedef struct _grpc_lb_v1_LoadBalanceResponse {
 
 /* Initializer values for message structs */
 #define grpc_lb_v1_Duration_init_default         {false, 0, false, 0}
+#define grpc_lb_v1_Timestamp_init_default        {false, 0, false, 0}
 #define grpc_lb_v1_LoadBalanceRequest_init_default {false, grpc_lb_v1_InitialLoadBalanceRequest_init_default, false, grpc_lb_v1_ClientStats_init_default}
 #define grpc_lb_v1_InitialLoadBalanceRequest_init_default {false, ""}
-#define grpc_lb_v1_ClientStats_init_default      {false, 0, false, 0, false, 0}
+#define grpc_lb_v1_ClientStats_init_default      {false, grpc_lb_v1_Timestamp_init_default, false, 0, false, 0, false, 0, false, 0, false, 0, false, 0}
 #define grpc_lb_v1_LoadBalanceResponse_init_default {false, grpc_lb_v1_InitialLoadBalanceResponse_init_default, false, grpc_lb_v1_ServerList_init_default}
 #define grpc_lb_v1_InitialLoadBalanceResponse_init_default {false, "", false, grpc_lb_v1_Duration_init_default}
 #define grpc_lb_v1_ServerList_init_default       {{{NULL}, NULL}, false, grpc_lb_v1_Duration_init_default}
-#define grpc_lb_v1_Server_init_default           {false, {0, {0}}, false, 0, false, "", false, 0}
+#define grpc_lb_v1_Server_init_default           {false, {0, {0}}, false, 0, false, "", false, 0, false, 0}
 #define grpc_lb_v1_Duration_init_zero            {false, 0, false, 0}
+#define grpc_lb_v1_Timestamp_init_zero           {false, 0, false, 0}
 #define grpc_lb_v1_LoadBalanceRequest_init_zero  {false, grpc_lb_v1_InitialLoadBalanceRequest_init_zero, false, grpc_lb_v1_ClientStats_init_zero}
 #define grpc_lb_v1_InitialLoadBalanceRequest_init_zero {false, ""}
-#define grpc_lb_v1_ClientStats_init_zero         {false, 0, false, 0, false, 0}
+#define grpc_lb_v1_ClientStats_init_zero         {false, grpc_lb_v1_Timestamp_init_zero, false, 0, false, 0, false, 0, false, 0, false, 0, false, 0}
 #define grpc_lb_v1_LoadBalanceResponse_init_zero {false, grpc_lb_v1_InitialLoadBalanceResponse_init_zero, false, grpc_lb_v1_ServerList_init_zero}
 #define grpc_lb_v1_InitialLoadBalanceResponse_init_zero {false, "", false, grpc_lb_v1_Duration_init_zero}
 #define grpc_lb_v1_ServerList_init_zero          {{{NULL}, NULL}, false, grpc_lb_v1_Duration_init_zero}
-#define grpc_lb_v1_Server_init_zero              {false, {0, {0}}, false, 0, false, "", false, 0}
+#define grpc_lb_v1_Server_init_zero              {false, {0, {0}}, false, 0, false, "", false, 0, false, 0}
 
 /* Field tags (for use in manual encoding/decoding) */
-#define grpc_lb_v1_ClientStats_total_requests_tag 1
-#define grpc_lb_v1_ClientStats_client_rpc_errors_tag 2
-#define grpc_lb_v1_ClientStats_dropped_requests_tag 3
 #define grpc_lb_v1_Duration_seconds_tag          1
 #define grpc_lb_v1_Duration_nanos_tag            2
 #define grpc_lb_v1_InitialLoadBalanceRequest_name_tag 1
 #define grpc_lb_v1_Server_ip_address_tag         1
 #define grpc_lb_v1_Server_port_tag               2
 #define grpc_lb_v1_Server_load_balance_token_tag 3
-#define grpc_lb_v1_Server_drop_request_tag       4
+#define grpc_lb_v1_Server_drop_for_rate_limiting_tag 4
+#define grpc_lb_v1_Server_drop_for_load_balancing_tag 5
+#define grpc_lb_v1_Timestamp_seconds_tag         1
+#define grpc_lb_v1_Timestamp_nanos_tag           2
+#define grpc_lb_v1_ClientStats_timestamp_tag     1
+#define grpc_lb_v1_ClientStats_num_calls_started_tag 2
+#define grpc_lb_v1_ClientStats_num_calls_finished_tag 3
+#define grpc_lb_v1_ClientStats_num_calls_finished_with_drop_for_rate_limiting_tag 4
+#define grpc_lb_v1_ClientStats_num_calls_finished_with_drop_for_load_balancing_tag 5
+#define grpc_lb_v1_ClientStats_num_calls_finished_with_client_failed_to_send_tag 6
+#define grpc_lb_v1_ClientStats_num_calls_finished_known_received_tag 7
 #define grpc_lb_v1_InitialLoadBalanceResponse_load_balancer_delegate_tag 1
 #define grpc_lb_v1_InitialLoadBalanceResponse_client_stats_report_interval_tag 2
-#define grpc_lb_v1_LoadBalanceRequest_initial_request_tag 1
-#define grpc_lb_v1_LoadBalanceRequest_client_stats_tag 2
 #define grpc_lb_v1_ServerList_servers_tag        1
 #define grpc_lb_v1_ServerList_expiration_interval_tag 3
+#define grpc_lb_v1_LoadBalanceRequest_initial_request_tag 1
+#define grpc_lb_v1_LoadBalanceRequest_client_stats_tag 2
 #define grpc_lb_v1_LoadBalanceResponse_initial_response_tag 1
 #define grpc_lb_v1_LoadBalanceResponse_server_list_tag 2
 
 /* Struct field encoding specification for nanopb */
 extern const pb_field_t grpc_lb_v1_Duration_fields[3];
+extern const pb_field_t grpc_lb_v1_Timestamp_fields[3];
 extern const pb_field_t grpc_lb_v1_LoadBalanceRequest_fields[3];
 extern const pb_field_t grpc_lb_v1_InitialLoadBalanceRequest_fields[2];
-extern const pb_field_t grpc_lb_v1_ClientStats_fields[4];
+extern const pb_field_t grpc_lb_v1_ClientStats_fields[8];
 extern const pb_field_t grpc_lb_v1_LoadBalanceResponse_fields[3];
 extern const pb_field_t grpc_lb_v1_InitialLoadBalanceResponse_fields[3];
 extern const pb_field_t grpc_lb_v1_ServerList_fields[3];
-extern const pb_field_t grpc_lb_v1_Server_fields[5];
+extern const pb_field_t grpc_lb_v1_Server_fields[6];
 
 /* Maximum encoded size of messages (where known) */
 #define grpc_lb_v1_Duration_size                 22
-#define grpc_lb_v1_LoadBalanceRequest_size       169
+#define grpc_lb_v1_Timestamp_size                22
+#define grpc_lb_v1_LoadBalanceRequest_size       226
 #define grpc_lb_v1_InitialLoadBalanceRequest_size 131
-#define grpc_lb_v1_ClientStats_size              33
+#define grpc_lb_v1_ClientStats_size              90
 #define grpc_lb_v1_LoadBalanceResponse_size      (98 + grpc_lb_v1_ServerList_size)
 #define grpc_lb_v1_InitialLoadBalanceResponse_size 90
 /* grpc_lb_v1_ServerList_size depends on runtime parameters */
-#define grpc_lb_v1_Server_size                   83
+#define grpc_lb_v1_Server_size                   85
 
 /* Message IDs (where set with "msgid" option) */
 #ifdef PB_MSGID

src/core/ext/filters/client_channel/lb_policy_factory.c

@@ -36,16 +36,18 @@
 #include <grpc/support/alloc.h>
 #include <grpc/support/string_util.h>
 
+#include "src/core/lib/channel/channel_args.h"
+
 #include "src/core/ext/filters/client_channel/lb_policy_factory.h"
+#include "src/core/ext/filters/client_channel/parse_address.h"
 
 grpc_lb_addresses* grpc_lb_addresses_create(
     size_t num_addresses, const grpc_lb_user_data_vtable* user_data_vtable) {
-  grpc_lb_addresses* addresses = gpr_malloc(sizeof(grpc_lb_addresses));
+  grpc_lb_addresses* addresses = gpr_zalloc(sizeof(grpc_lb_addresses));
   addresses->num_addresses = num_addresses;
   addresses->user_data_vtable = user_data_vtable;
   const size_t addresses_size = sizeof(grpc_lb_address) * num_addresses;
-  addresses->addresses = gpr_malloc(addresses_size);
-  memset(addresses->addresses, 0, addresses_size);
+  addresses->addresses = gpr_zalloc(addresses_size);
   return addresses;
 }
 
@@ -69,7 +71,7 @@ grpc_lb_addresses* grpc_lb_addresses_copy(const grpc_lb_addresses* addresses) {
 
 void grpc_lb_addresses_set_address(grpc_lb_addresses* addresses, size_t index,
                                    void* address, size_t address_len,
-                                   bool is_balancer, char* balancer_name,
+                                   bool is_balancer, const char* balancer_name,
                                    void* user_data) {
   GPR_ASSERT(index < addresses->num_addresses);
   if (user_data != NULL) GPR_ASSERT(addresses->user_data_vtable != NULL);
@@ -77,10 +79,22 @@ void grpc_lb_addresses_set_address(grpc_lb_addresses* addresses, size_t index,
   memcpy(target->address.addr, address, address_len);
   target->address.len = address_len;
   target->is_balancer = is_balancer;
-  target->balancer_name = balancer_name;
+  target->balancer_name = gpr_strdup(balancer_name);
   target->user_data = user_data;
 }
 
+bool grpc_lb_addresses_set_address_from_uri(grpc_lb_addresses* addresses,
+                                            size_t index, const grpc_uri* uri,
+                                            bool is_balancer,
+                                            const char* balancer_name,
+                                            void* user_data) {
+  grpc_resolved_address address;
+  if (!grpc_parse_uri(uri, &address)) return false;
+  grpc_lb_addresses_set_address(addresses, index, address.addr, address.len,
+                                is_balancer, balancer_name, user_data);
+  return true;
+}
+
 int grpc_lb_addresses_cmp(const grpc_lb_addresses* addresses1,
                           const grpc_lb_addresses* addresses2) {
   if (addresses1->num_addresses > addresses2->num_addresses) return 1;
@@ -147,6 +161,15 @@ grpc_arg grpc_lb_addresses_create_channel_arg(
   return arg;
 }
 
+grpc_lb_addresses* grpc_lb_addresses_find_channel_arg(
+    const grpc_channel_args* channel_args) {
+  const grpc_arg* lb_addresses_arg =
+      grpc_channel_args_find(channel_args, GRPC_ARG_LB_ADDRESSES);
+  if (lb_addresses_arg == NULL || lb_addresses_arg->type != GRPC_ARG_POINTER)
+    return NULL;
+  return lb_addresses_arg->value.pointer.p;
+}
+
 void grpc_lb_policy_factory_ref(grpc_lb_policy_factory* factory) {
   factory->vtable->ref(factory);
 }

src/core/ext/filters/client_channel/lb_policy_factory.h

@@ -34,12 +34,13 @@
 #ifndef GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_LB_POLICY_FACTORY_H
 #define GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_LB_POLICY_FACTORY_H
 
-#include "src/core/ext/filters/client_channel/client_channel_factory.h"
-#include "src/core/ext/filters/client_channel/lb_policy.h"
-
 #include "src/core/lib/iomgr/exec_ctx.h"
 #include "src/core/lib/iomgr/resolve_address.h"
 
+#include "src/core/ext/filters/client_channel/client_channel_factory.h"
+#include "src/core/ext/filters/client_channel/lb_policy.h"
+#include "src/core/ext/filters/client_channel/uri_parser.h"
+
 // Channel arg key for grpc_lb_addresses.
 #define GRPC_ARG_LB_ADDRESSES "grpc.lb_addresses"
 
@@ -88,7 +89,16 @@ grpc_lb_addresses *grpc_lb_addresses_copy(const grpc_lb_addresses *addresses);
  * Takes ownership of \a balancer_name. */
 void grpc_lb_addresses_set_address(grpc_lb_addresses *addresses, size_t index,
                                    void *address, size_t address_len,
-                                   bool is_balancer, char *balancer_name,
+                                   bool is_balancer, const char *balancer_name,
+                                   void *user_data);
+
+/** Sets the value of the address at index \a index of \a addresses from \a uri.
+ * Returns true upon success, false otherwise. Takes ownership of \a
+ * balancer_name. */
+bool grpc_lb_addresses_set_address_from_uri(grpc_lb_addresses *addresses,
+                                            size_t index, const grpc_uri *uri,
+                                            bool is_balancer,
+                                            const char *balancer_name,
                                             void *user_data);
 
 /** Compares \a addresses1 and \a addresses2. */
@@ -103,6 +113,10 @@ void grpc_lb_addresses_destroy(grpc_exec_ctx *exec_ctx,
 grpc_arg grpc_lb_addresses_create_channel_arg(
     const grpc_lb_addresses *addresses);
 
+/** Returns the \a grpc_lb_addresses instance in \a channel_args or NULL */
+grpc_lb_addresses *grpc_lb_addresses_find_channel_arg(
+    const grpc_channel_args *channel_args);
+
 /** Arguments passed to LB policies. */
 typedef struct grpc_lb_policy_args {
   grpc_client_channel_factory *client_channel_factory;

src/core/ext/filters/client_channel/parse_address.c

@@ -48,7 +48,12 @@
 
 #ifdef GRPC_HAVE_UNIX_SOCKET
 
-int parse_unix(grpc_uri *uri, grpc_resolved_address *resolved_addr) {
+bool grpc_parse_unix(const grpc_uri *uri,
+                     grpc_resolved_address *resolved_addr) {
+  if (strcmp("unix", uri->scheme) != 0) {
+    gpr_log(GPR_ERROR, "Expected 'unix' scheme, got '%s'", uri->scheme);
+    return false;
+  }
   struct sockaddr_un *un = (struct sockaddr_un *)resolved_addr->addr;
   const size_t maxlen = sizeof(un->sun_path);
   const size_t path_len = strnlen(uri->path, maxlen);
@@ -61,21 +66,29 @@ int parse_unix(grpc_uri *uri, grpc_resolved_address *resolved_addr) {
 
 #else /* GRPC_HAVE_UNIX_SOCKET */
 
-int parse_unix(grpc_uri *uri, grpc_resolved_address *resolved_addr) { abort(); }
+bool grpc_parse_unix(const grpc_uri *uri,
+                     grpc_resolved_address *resolved_addr) {
+  abort();
+}
 
 #endif /* GRPC_HAVE_UNIX_SOCKET */
 
-int parse_ipv4(grpc_uri *uri, grpc_resolved_address *resolved_addr) {
+bool grpc_parse_ipv4(const grpc_uri *uri,
+                     grpc_resolved_address *resolved_addr) {
+  if (strcmp("ipv4", uri->scheme) != 0) {
+    gpr_log(GPR_ERROR, "Expected 'ipv4' scheme, got '%s'", uri->scheme);
+    return false;
+  }
   const char *host_port = uri->path;
   char *host;
   char *port;
   int port_num;
-  int result = 0;
+  bool result = false;
   struct sockaddr_in *in = (struct sockaddr_in *)resolved_addr->addr;
 
   if (*host_port == '/') ++host_port;
   if (!gpr_split_host_port(host_port, &host, &port)) {
-    return 0;
+    return false;
   }
 
   memset(resolved_addr, 0, sizeof(grpc_resolved_address));
@@ -98,14 +111,19 @@ int parse_ipv4(grpc_uri *uri, grpc_resolved_address *resolved_addr) {
     goto done;
   }
 
-  result = 1;
+  result = true;
 done:
   gpr_free(host);
   gpr_free(port);
   return result;
 }
 
-int parse_ipv6(grpc_uri *uri, grpc_resolved_address *resolved_addr) {
+bool grpc_parse_ipv6(const grpc_uri *uri,
+                     grpc_resolved_address *resolved_addr) {
+  if (strcmp("ipv6", uri->scheme) != 0) {
+    gpr_log(GPR_ERROR, "Expected 'ipv6' scheme, got '%s'", uri->scheme);
+    return false;
+  }
   const char *host_port = uri->path;
   char *host;
   char *port;
@@ -168,3 +186,15 @@ done:
   gpr_free(port);
   return result;
 }
+
+bool grpc_parse_uri(const grpc_uri *uri, grpc_resolved_address *resolved_addr) {
+  if (strcmp("unix", uri->scheme) == 0) {
+    return grpc_parse_unix(uri, resolved_addr);
+  } else if (strcmp("ipv4", uri->scheme) == 0) {
+    return grpc_parse_ipv4(uri, resolved_addr);
+  } else if (strcmp("ipv6", uri->scheme) == 0) {
+    return grpc_parse_ipv6(uri, resolved_addr);
+  }
+  gpr_log(GPR_ERROR, "Can't parse scheme '%s'", uri->scheme);
+  return false;
+}

src/core/ext/filters/client_channel/parse_address.h

@@ -39,16 +39,19 @@
 #include "src/core/ext/filters/client_channel/uri_parser.h"
 #include "src/core/lib/iomgr/resolve_address.h"
 
-/** Populate \a addr and \a len from \a uri, whose path is expected to contain a
+/** Populate \a resolved_addr from \a uri, whose path is expected to contain a
  * unix socket path. Returns true upon success. */
-int parse_unix(grpc_uri *uri, grpc_resolved_address *resolved_addr);
+bool grpc_parse_unix(const grpc_uri *uri, grpc_resolved_address *resolved_addr);
 
-/** Populate /a addr and \a len from \a uri, whose path is expected to contain a
- * host:port pair. Returns true upon success. */
-int parse_ipv4(grpc_uri *uri, grpc_resolved_address *resolved_addr);
+/** Populate \a resolved_addr from \a uri, whose path is expected to contain an
+ * IPv4 host:port pair. Returns true upon success. */
+bool grpc_parse_ipv4(const grpc_uri *uri, grpc_resolved_address *resolved_addr);
 
-/** Populate /a addr and \a len from \a uri, whose path is expected to contain a
- * host:port pair. Returns true upon success. */
-int parse_ipv6(grpc_uri *uri, grpc_resolved_address *resolved_addr);
+/** Populate \a resolved_addr from \a uri, whose path is expected to contain an
+ * IPv6 host:port pair. Returns true upon success. */
+bool grpc_parse_ipv6(const grpc_uri *uri, grpc_resolved_address *resolved_addr);
+
+/** Populate \a resolved_addr from \a uri. Returns true upon success. */
+bool grpc_parse_uri(const grpc_uri *uri, grpc_resolved_address *resolved_addr);
 
 #endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_PARSE_ADDRESS_H */

src/core/ext/filters/client_channel/resolver/sockaddr/sockaddr_resolver.c

@@ -157,7 +157,7 @@ static void do_nothing(void *ignored) {}
 
 static grpc_resolver *sockaddr_create(grpc_exec_ctx *exec_ctx,
                                       grpc_resolver_args *args,
-                                      int parse(grpc_uri *uri,
+                                      bool parse(const grpc_uri *uri,
                                                  grpc_resolved_address *dst)) {
   if (0 != strcmp(args->uri->authority, "")) {
     gpr_log(GPR_ERROR, "authority based uri's not supported by the %s scheme",
@@ -209,7 +209,7 @@ static void sockaddr_factory_unref(grpc_resolver_factory *factory) {}
   static grpc_resolver *name##_factory_create_resolver(                     \
       grpc_exec_ctx *exec_ctx, grpc_resolver_factory *factory,              \
       grpc_resolver_args *args) {                                           \
-    return sockaddr_create(exec_ctx, args, parse_##name);                   \
+    return sockaddr_create(exec_ctx, args, grpc_parse_##name);              \
   }                                                                         \
   static const grpc_resolver_factory_vtable name##_factory_vtable = {       \
       sockaddr_factory_ref, sockaddr_factory_unref,                         \

src/core/ext/filters/client_channel/subchannel.c

@@ -59,9 +59,9 @@
 #define INTERNAL_REF_BITS 16
 #define STRONG_REF_MASK (~(gpr_atm)((1 << INTERNAL_REF_BITS) - 1))
 
-#define GRPC_SUBCHANNEL_MIN_CONNECT_TIMEOUT_SECONDS 20
 #define GRPC_SUBCHANNEL_INITIAL_CONNECT_BACKOFF_SECONDS 1
 #define GRPC_SUBCHANNEL_RECONNECT_BACKOFF_MULTIPLIER 1.6
+#define GRPC_SUBCHANNEL_RECONNECT_MIN_BACKOFF_SECONDS 20
 #define GRPC_SUBCHANNEL_RECONNECT_MAX_BACKOFF_SECONDS 120
 #define GRPC_SUBCHANNEL_RECONNECT_JITTER 0.2
 
@@ -353,8 +353,8 @@ grpc_subchannel *grpc_subchannel_create(grpc_exec_ctx *exec_ctx,
                                "subchannel");
   int initial_backoff_ms =
       GRPC_SUBCHANNEL_INITIAL_CONNECT_BACKOFF_SECONDS * 1000;
+  int min_backoff_ms = GRPC_SUBCHANNEL_RECONNECT_MIN_BACKOFF_SECONDS * 1000;
   int max_backoff_ms = GRPC_SUBCHANNEL_RECONNECT_MAX_BACKOFF_SECONDS * 1000;
-  int min_backoff_ms = GRPC_SUBCHANNEL_MIN_CONNECT_TIMEOUT_SECONDS * 1000;
   bool fixed_reconnect_backoff = false;
   if (c->args) {
     for (size_t i = 0; i < c->args->num_args; i++) {
@@ -365,6 +365,12 @@ grpc_subchannel *grpc_subchannel_create(grpc_exec_ctx *exec_ctx,
             grpc_channel_arg_get_integer(
                 &c->args->args[i],
                 (grpc_integer_options){initial_backoff_ms, 100, INT_MAX});
+      } else if (0 == strcmp(c->args->args[i].key,
+                             GRPC_ARG_MIN_RECONNECT_BACKOFF_MS)) {
+        fixed_reconnect_backoff = false;
+        min_backoff_ms = grpc_channel_arg_get_integer(
+            &c->args->args[i],
+            (grpc_integer_options){min_backoff_ms, 100, INT_MAX});
       } else if (0 == strcmp(c->args->args[i].key,
                              GRPC_ARG_MAX_RECONNECT_BACKOFF_MS)) {
         fixed_reconnect_backoff = false;
@@ -797,13 +803,7 @@ static void grpc_uri_to_sockaddr(grpc_exec_ctx *exec_ctx, const char *uri_str,
                                  grpc_resolved_address *addr) {
   grpc_uri *uri = grpc_uri_parse(exec_ctx, uri_str, 0 /* suppress_errors */);
   GPR_ASSERT(uri != NULL);
-  if (strcmp(uri->scheme, "ipv4") == 0) {
-    GPR_ASSERT(parse_ipv4(uri, addr));
-  } else if (strcmp(uri->scheme, "ipv6") == 0) {
-    GPR_ASSERT(parse_ipv6(uri, addr));
-  } else {
-    GPR_ASSERT(parse_unix(uri, addr));
-  }
+  if (!grpc_parse_uri(uri, addr)) memset(addr, 0, sizeof(*addr));
   grpc_uri_destroy(uri);
 }
 

src/core/ext/filters/client_channel/uri_parser.c

@@ -50,7 +50,7 @@
 #define NOT_SET (~(size_t)0)
 
 static grpc_uri *bad_uri(const char *uri_text, size_t pos, const char *section,
-                         int suppress_errors) {
+                         bool suppress_errors) {
   char *line_prefix;
   size_t pfx_len;
 
@@ -83,6 +83,11 @@ static char *decode_and_copy_component(grpc_exec_ctx *exec_ctx, const char *src,
   return out;
 }
 
+static bool valid_hex(char c) {
+  return ((c >= 'a') && (c <= 'f')) || ((c >= 'A') && (c <= 'F')) ||
+         ((c >= '0') && (c <= '9'));
+}
+
 /** Returns how many chars to advance if \a uri_text[i] begins a valid \a pchar
  * production. If \a uri_text[i] introduces an invalid \a pchar (such as percent
  * sign not followed by two hex digits), NOT_SET is returned. */
@@ -93,28 +98,37 @@ static size_t parse_pchar(const char *uri_text, size_t i) {
    * sub-delims = "!" / "$" / "&" / "'" / "(" / ")"
    / "*" / "+" / "," / ";" / "=" */
   char c = uri_text[i];
-  if (((c >= 'A') && (c <= 'Z')) || ((c >= 'a') && (c <= 'z')) ||
-      ((c >= '0') && (c <= '9')) ||
-      (c == '-' || c == '.' || c == '_' || c == '~') || /* unreserved */
-      (c == '!' || c == '$' || c == '&' || c == '\'' || c == '$' || c == '&' ||
-       c == '(' || c == ')' || c == '*' || c == '+' || c == ',' || c == ';' ||
-       c == '=') /* sub-delims */) {
+  switch (c) {
+    default:
+      if (((c >= 'a') && (c <= 'z')) || ((c >= 'A') && (c <= 'Z')) ||
+          ((c >= '0') && (c <= '9'))) {
         return 1;
       }
-  if (c == '%') { /* pct-encoded */
-    size_t j;
-    if (uri_text[i + 1] == 0 || uri_text[i + 2] == 0) {
-      return NOT_SET;
+      break;
+    case ':':
+    case '@':
+    case '-':
+    case '.':
+    case '_':
+    case '~':
+    case '!':
+    case '$':
+    case '&':
+    case '\'':
+    case '(':
+    case ')':
+    case '*':
+    case '+':
+    case ',':
+    case ';':
+    case '=':
+      return 1;
+    case '%': /* pct-encoded */
+      if (valid_hex(uri_text[i + 1]) && valid_hex(uri_text[i + 2])) {
+        return 2;
       }
-    for (j = i + 1; j < 2; j++) {
-      c = uri_text[j];
-      if (!(((c >= '0') && (c <= '9')) || ((c >= 'a') && (c <= 'f')) ||
-            ((c >= 'A') && (c <= 'F')))) {
       return NOT_SET;
   }
-    }
-    return 2;
-  }
   return 0;
 }
 
@@ -183,7 +197,7 @@ static void parse_query_parts(grpc_uri *uri) {
 }
 
 grpc_uri *grpc_uri_parse(grpc_exec_ctx *exec_ctx, const char *uri_text,
-                         int suppress_errors) {
+                         bool suppress_errors) {
   grpc_uri *uri;
   size_t scheme_begin = 0;
   size_t scheme_end = NOT_SET;

src/core/ext/filters/client_channel/uri_parser.h

@@ -53,7 +53,7 @@ typedef struct {
 
 /** parse a uri, return NULL on failure */
 grpc_uri *grpc_uri_parse(grpc_exec_ctx *exec_ctx, const char *uri_text,
-                         int suppress_errors);
+                         bool suppress_errors);
 
 /** return the part of a query string after the '=' in "?key=xxx&...", or NULL
  * if key is not present */

src/core/ext/filters/http/client/http_client_filter.c

@@ -220,8 +220,11 @@ static void continue_send_message(grpc_exec_ctx *exec_ctx,
   call_data *calld = elem->call_data;
   uint8_t *wrptr = calld->payload_bytes;
   while (grpc_byte_stream_next(
-      exec_ctx, calld->send_op->payload->send_message.send_message,
-      &calld->incoming_slice, ~(size_t)0, &calld->got_slice)) {
+      exec_ctx, calld->send_op->payload->send_message.send_message, ~(size_t)0,
+      &calld->got_slice)) {
+    grpc_byte_stream_pull(exec_ctx,
+                          calld->send_op->payload->send_message.send_message,
+                          &calld->incoming_slice);
     if (GRPC_SLICE_LENGTH(calld->incoming_slice) > 0) {
       memcpy(wrptr, GRPC_SLICE_START_PTR(calld->incoming_slice),
              GRPC_SLICE_LENGTH(calld->incoming_slice));
@@ -239,6 +242,13 @@ static void got_slice(grpc_exec_ctx *exec_ctx, void *elemp, grpc_error *error) {
   grpc_call_element *elem = elemp;
   call_data *calld = elem->call_data;
   calld->send_message_blocked = false;
+  if (GRPC_ERROR_NONE !=
+      grpc_byte_stream_pull(exec_ctx,
+                            calld->send_op->payload->send_message.send_message,
+                            &calld->incoming_slice)) {
+    /* Should never reach here */
+    abort();
+  }
   grpc_slice_buffer_add(&calld->slices, calld->incoming_slice);
   if (calld->send_length == calld->slices.length) {
     /* Pass down the original send_message op that was blocked.*/
@@ -313,7 +323,6 @@ static grpc_error *hc_mutate_op(grpc_exec_ctx *exec_ctx,
         estimated_len += grpc_base64_estimate_encoded_size(
             op->payload->send_message.send_message->length, k_url_safe,
             k_multi_line);
-        estimated_len += 1; /* for the trailing 0 */
         grpc_slice path_with_query_slice = grpc_slice_malloc(estimated_len);
 
         /* memcopy individual pieces into this slice */
@@ -334,10 +343,8 @@ static grpc_error *hc_mutate_op(grpc_exec_ctx *exec_ctx,
          */
         char *t = (char *)GRPC_SLICE_START_PTR(path_with_query_slice);
         /* safe to use strlen since base64_encode will always add '\0' */
-        size_t path_length = strlen(t) + 1;
-        *(t + path_length) = '\0';
         path_with_query_slice =
-            grpc_slice_sub(path_with_query_slice, 0, path_length);
+            grpc_slice_sub_no_ref(path_with_query_slice, 0, strlen(t));
 
         /* substitute previous path with the new path+query */
         grpc_mdelem mdelem_path_and_query = grpc_mdelem_from_slices(
@@ -351,7 +358,6 @@ static grpc_error *hc_mutate_op(grpc_exec_ctx *exec_ctx,
         calld->on_complete = op->on_complete;
         op->on_complete = &calld->hc_on_complete;
         op->send_message = false;
-        grpc_slice_unref_internal(exec_ctx, path_with_query_slice);
       } else {
         /* Not all data is available. Fall back to POST. */
         gpr_log(GPR_DEBUG,

src/core/ext/filters/http/message_compress/message_compress_filter.c

@@ -239,6 +239,13 @@ static void finish_send_message(grpc_exec_ctx *exec_ctx,
 static void got_slice(grpc_exec_ctx *exec_ctx, void *elemp, grpc_error *error) {
   grpc_call_element *elem = elemp;
   call_data *calld = elem->call_data;
+  if (GRPC_ERROR_NONE !=
+      grpc_byte_stream_pull(exec_ctx,
+                            calld->send_op->payload->send_message.send_message,
+                            &calld->incoming_slice)) {
+    /* Should never reach here */
+    abort();
+  }
   grpc_slice_buffer_add(&calld->slices, calld->incoming_slice);
   if (calld->send_length == calld->slices.length) {
     finish_send_message(exec_ctx, elem);
@@ -251,8 +258,11 @@ static void continue_send_message(grpc_exec_ctx *exec_ctx,
                                   grpc_call_element *elem) {
   call_data *calld = elem->call_data;
   while (grpc_byte_stream_next(
-      exec_ctx, calld->send_op->payload->send_message.send_message,
-      &calld->incoming_slice, ~(size_t)0, &calld->got_slice)) {
+      exec_ctx, calld->send_op->payload->send_message.send_message, ~(size_t)0,
+      &calld->got_slice)) {
+    grpc_byte_stream_pull(exec_ctx,
+                          calld->send_op->payload->send_message.send_message,
+                          &calld->incoming_slice);
     grpc_slice_buffer_add(&calld->slices, calld->incoming_slice);
     if (calld->send_length == calld->slices.length) {
       finish_send_message(exec_ctx, elem);

src/core/ext/filters/http/server/http_server_filter.c

@@ -240,9 +240,9 @@ static grpc_error *server_filter_incoming_metadata(grpc_exec_ctx *exec_ctx,
       const int k_url_safe = 1;
       grpc_slice_buffer_add(
           &calld->read_slice_buffer,
-          grpc_base64_decode(exec_ctx,
-                             (const char *)GRPC_SLICE_START_PTR(query_slice),
-                             k_url_safe));
+          grpc_base64_decode_with_len(
+              exec_ctx, (const char *)GRPC_SLICE_START_PTR(query_slice),
+              GRPC_SLICE_LENGTH(query_slice), k_url_safe));
       grpc_slice_buffer_stream_init(&calld->read_stream,
                                     &calld->read_slice_buffer, 0);
       calld->seen_path_with_query = true;

src/core/ext/filters/load_reporting/load_reporting.c

@@ -47,23 +47,6 @@
 #include "src/core/lib/surface/call.h"
 #include "src/core/lib/surface/channel_init.h"
 
-static void destroy_lr_cost_context(void *c) {
-  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
-  grpc_load_reporting_cost_context *cost_ctx = c;
-  for (size_t i = 0; i < cost_ctx->values_count; ++i) {
-    grpc_slice_unref_internal(&exec_ctx, cost_ctx->values[i]);
-  }
-  grpc_exec_ctx_finish(&exec_ctx);
-  gpr_free(cost_ctx->values);
-  gpr_free(cost_ctx);
-}
-
-void grpc_call_set_load_reporting_cost_context(
-    grpc_call *call, grpc_load_reporting_cost_context *ctx) {
-  grpc_call_context_set(call, GRPC_CONTEXT_LR_COST, ctx,
-                        destroy_lr_cost_context);
-}
-
 static bool is_load_reporting_enabled(const grpc_channel_args *a) {
   return grpc_channel_arg_get_bool(
       grpc_channel_args_find(a, GRPC_ARG_ENABLE_LOAD_REPORTING), false);

src/core/ext/filters/load_reporting/load_reporting_filter.c

@@ -48,6 +48,8 @@
 
 typedef struct call_data {
   intptr_t id; /**< an id unique to the call */
+  bool have_trailing_md_string;
+  grpc_slice trailing_md_string;
   bool have_initial_md_string;
   grpc_slice initial_md_string;
   bool have_service_method;
@@ -140,6 +142,9 @@ static void destroy_call_elem(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
   if (calld->have_initial_md_string) {
     grpc_slice_unref_internal(exec_ctx, calld->initial_md_string);
   }
+  if (calld->have_trailing_md_string) {
+    grpc_slice_unref_internal(exec_ctx, calld->trailing_md_string);
+  }
   if (calld->have_service_method) {
     grpc_slice_unref_internal(exec_ctx, calld->service_method);
   }
@@ -183,6 +188,18 @@ static void destroy_channel_elem(grpc_exec_ctx *exec_ctx,
   */
 }
 
+static grpc_filtered_mdelem lr_trailing_md_filter(grpc_exec_ctx *exec_ctx,
+                                                  void *user_data,
+                                                  grpc_mdelem md) {
+  grpc_call_element *elem = user_data;
+  call_data *calld = elem->call_data;
+  if (grpc_slice_eq(GRPC_MDKEY(md), GRPC_MDSTR_LB_COST_BIN)) {
+    calld->trailing_md_string = GRPC_MDVALUE(md);
+    return GRPC_FILTERED_REMOVE();
+  }
+  return GRPC_FILTERED_MDELEM(md);
+}
+
 static void lr_start_transport_stream_op_batch(
     grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
     grpc_transport_stream_op_batch *op) {
@@ -190,13 +207,21 @@ static void lr_start_transport_stream_op_batch(
   call_data *calld = elem->call_data;
 
   if (op->recv_initial_metadata) {
+    /* substitute our callback for the higher callback */
     calld->recv_initial_metadata =
         op->payload->recv_initial_metadata.recv_initial_metadata;
-    /* substitute our callback for the higher callback */
     calld->ops_recv_initial_metadata_ready =
         op->payload->recv_initial_metadata.recv_initial_metadata_ready;
     op->payload->recv_initial_metadata.recv_initial_metadata_ready =
         &calld->on_initial_md_ready;
+  } else if (op->send_trailing_metadata) {
+    GRPC_LOG_IF_ERROR(
+        "grpc_metadata_batch_filter",
+        grpc_metadata_batch_filter(
+            exec_ctx,
+            op->payload->send_trailing_metadata.send_trailing_metadata,
+            lr_trailing_md_filter, elem,
+            "LR trailing metadata filtering error"));
   }
   grpc_call_next_op(exec_ctx, elem, op);
 

src/core/ext/transport/chttp2/transport/chttp2_transport.c

@@ -44,6 +44,7 @@
 #include <grpc/support/string_util.h>
 #include <grpc/support/useful.h>
 
+#include "src/core/ext/transport/chttp2/transport/frame_data.h"
 #include "src/core/ext/transport/chttp2/transport/internal.h"
 #include "src/core/ext/transport/chttp2/transport/varint.h"
 #include "src/core/lib/channel/channel_args.h"
@@ -129,6 +130,11 @@ static void incoming_byte_stream_update_flow_control(grpc_exec_ctx *exec_ctx,
 static void incoming_byte_stream_destroy_locked(grpc_exec_ctx *exec_ctx,
                                                 void *byte_stream,
                                                 grpc_error *error_ignored);
+static void incoming_byte_stream_publish_error(
+    grpc_exec_ctx *exec_ctx, grpc_chttp2_incoming_byte_stream *bs,
+    grpc_error *error);
+static void incoming_byte_stream_unref(grpc_exec_ctx *exec_ctx,
+                                       grpc_chttp2_incoming_byte_stream *bs);
 
 static void benign_reclaimer_locked(grpc_exec_ctx *exec_ctx, void *t,
                                     grpc_error *error);
@@ -174,6 +180,9 @@ static void finish_keepalive_ping_locked(grpc_exec_ctx *exec_ctx, void *arg,
 static void keepalive_watchdog_fired_locked(grpc_exec_ctx *exec_ctx, void *arg,
                                             grpc_error *error);
 
+static void reset_byte_stream(grpc_exec_ctx *exec_ctx, void *arg,
+                              grpc_error *error);
+
 /*******************************************************************************
  * CONSTRUCTION/DESTRUCTION/REFCOUNTING
  */
@@ -550,6 +559,10 @@ static void init_transport(grpc_exec_ctx *exec_ctx, grpc_chttp2_transport *t,
         exec_ctx, &t->keepalive_ping_timer,
         gpr_time_add(gpr_now(GPR_CLOCK_MONOTONIC), t->keepalive_time),
         &t->init_keepalive_ping_locked, gpr_now(GPR_CLOCK_MONOTONIC));
+  } else {
+    /* Use GRPC_CHTTP2_KEEPALIVE_STATE_DISABLED to indicate there are no
+       inflight keeaplive timers */
+    t->keepalive_state = GRPC_CHTTP2_KEEPALIVE_STATE_DISABLED;
   }
 
   grpc_chttp2_initiate_write(exec_ctx, t, false, "init");
@@ -598,22 +611,19 @@ static void close_transport_locked(grpc_exec_ctx *exec_ctx,
     connectivity_state_set(exec_ctx, t, GRPC_CHANNEL_SHUTDOWN,
                            GRPC_ERROR_REF(error), "close_transport");
     grpc_endpoint_shutdown(exec_ctx, t->ep, GRPC_ERROR_REF(error));
-    if (t->is_client) {
     switch (t->keepalive_state) {
-        case GRPC_CHTTP2_KEEPALIVE_STATE_WAITING: {
+      case GRPC_CHTTP2_KEEPALIVE_STATE_WAITING:
         grpc_timer_cancel(exec_ctx, &t->keepalive_ping_timer);
         break;
-        }
-        case GRPC_CHTTP2_KEEPALIVE_STATE_PINGING: {
+      case GRPC_CHTTP2_KEEPALIVE_STATE_PINGING:
         grpc_timer_cancel(exec_ctx, &t->keepalive_ping_timer);
         grpc_timer_cancel(exec_ctx, &t->keepalive_watchdog_timer);
         break;
-        }
-        case GRPC_CHTTP2_KEEPALIVE_STATE_DYING: {
+      case GRPC_CHTTP2_KEEPALIVE_STATE_DYING:
+      case GRPC_CHTTP2_KEEPALIVE_STATE_DISABLED:
+        /* keepalive timers are not set in these two states */
         break;
     }
-      }
-    }
 
     /* flush writable stream list to avoid dangling references */
     grpc_chttp2_stream *s;
@@ -655,7 +665,6 @@ static int init_stream(grpc_exec_ctx *exec_ctx, grpc_transport *gt,
   /* We reserve one 'active stream' that's dropped when the stream is
      read-closed. The others are for incoming_byte_streams that are actively
      reading */
-  gpr_ref_init(&s->active_streams, 1);
   GRPC_CHTTP2_STREAM_REF(s, "chttp2");
 
   grpc_chttp2_incoming_metadata_buffer_init(&s->metadata_buffer[0], arena);
@@ -665,6 +674,11 @@ static int init_stream(grpc_exec_ctx *exec_ctx, grpc_transport *gt,
   s->deadline = gpr_inf_future(GPR_CLOCK_MONOTONIC);
   grpc_closure_init(&s->complete_fetch_locked, complete_fetch_locked, s,
                     grpc_schedule_on_exec_ctx);
+  grpc_slice_buffer_init(&s->unprocessed_incoming_frames_buffer);
+  grpc_slice_buffer_init(&s->frame_storage);
+  s->pending_byte_stream = false;
+  grpc_closure_init(&s->reset_byte_stream, reset_byte_stream, s,
+                    grpc_combiner_scheduler(t->combiner, false));
 
   GRPC_CHTTP2_REF_TRANSPORT(t, "stream");
 
@@ -682,7 +696,6 @@ static int init_stream(grpc_exec_ctx *exec_ctx, grpc_transport *gt,
 
 static void destroy_stream_locked(grpc_exec_ctx *exec_ctx, void *sp,
                                   grpc_error *error) {
-  grpc_byte_stream *bs;
   grpc_chttp2_stream *s = sp;
   grpc_chttp2_transport *t = s->t;
 
@@ -693,9 +706,9 @@ static void destroy_stream_locked(grpc_exec_ctx *exec_ctx, void *sp,
     GPR_ASSERT(grpc_chttp2_stream_map_find(&t->stream_map, s->id) == NULL);
   }
 
-  while ((bs = grpc_chttp2_incoming_frame_queue_pop(&s->incoming_frames))) {
-    incoming_byte_stream_destroy_locked(exec_ctx, bs, GRPC_ERROR_NONE);
-  }
+  grpc_slice_buffer_destroy_internal(exec_ctx,
+                                     &s->unprocessed_incoming_frames_buffer);
+  grpc_slice_buffer_destroy_internal(exec_ctx, &s->frame_storage);
 
   grpc_chttp2_list_remove_stalled_by_transport(t, s);
   grpc_chttp2_list_remove_stalled_by_stream(t, s);
@@ -722,6 +735,7 @@ static void destroy_stream_locked(grpc_exec_ctx *exec_ctx, void *sp,
   grpc_slice_buffer_destroy_internal(exec_ctx, &s->flow_controlled_buffer);
   GRPC_ERROR_UNREF(s->read_closed_error);
   GRPC_ERROR_UNREF(s->write_closed_error);
+  GRPC_ERROR_UNREF(s->byte_stream_error);
 
   if (s->incoming_window_delta > 0) {
     GRPC_CHTTP2_FLOW_DEBIT_STREAM_INCOMING_WINDOW_DELTA(
@@ -1175,8 +1189,9 @@ static void continue_fetching_send_locked(grpc_exec_ctx *exec_ctx,
       s->fetching_send_message = NULL;
       return; /* early out */
     } else if (grpc_byte_stream_next(exec_ctx, s->fetching_send_message,
-                                     &s->fetching_slice, UINT32_MAX,
-                                     &s->complete_fetch_locked)) {
+                                     UINT32_MAX, &s->complete_fetch_locked)) {
+      grpc_byte_stream_pull(exec_ctx, s->fetching_send_message,
+                            &s->fetching_slice);
       add_fetched_slice_locked(exec_ctx, t, s);
     }
   }
@@ -1186,10 +1201,16 @@ static void complete_fetch_locked(grpc_exec_ctx *exec_ctx, void *gs,
                                   grpc_error *error) {
   grpc_chttp2_stream *s = gs;
   grpc_chttp2_transport *t = s->t;
+  if (error == GRPC_ERROR_NONE) {
+    error = grpc_byte_stream_pull(exec_ctx, s->fetching_send_message,
+                                  &s->fetching_slice);
     if (error == GRPC_ERROR_NONE) {
       add_fetched_slice_locked(exec_ctx, t, s);
       continue_fetching_send_locked(exec_ctx, t, s);
-  } else {
+    }
+  }
+
+  if (error != GRPC_ERROR_NONE) {
     /* TODO(ctiller): what to do here */
     abort();
   }
@@ -1421,12 +1442,20 @@ static void perform_stream_op_locked(grpc_exec_ctx *exec_ctx, void *stream_op,
   }
 
   if (op->recv_message) {
+    size_t already_received;
     GPR_ASSERT(s->recv_message_ready == NULL);
+    GPR_ASSERT(!s->pending_byte_stream);
     s->recv_message_ready = op_payload->recv_message.recv_message_ready;
     s->recv_message = op_payload->recv_message.recv_message;
-    if (s->id != 0 &&
-        (s->incoming_frames.head == NULL || s->incoming_frames.head->is_tail)) {
-      incoming_byte_stream_update_flow_control(exec_ctx, t, s, 5, 0);
+    if (s->id != 0) {
+      if (s->pending_byte_stream) {
+        already_received = s->frame_storage.length;
+      } else {
+        already_received = s->frame_storage.length +
+                           s->unprocessed_incoming_frames_buffer.length;
+      }
+      incoming_byte_stream_update_flow_control(exec_ctx, t, s, 5,
+                                               already_received);
     }
     grpc_chttp2_maybe_complete_recv_message(exec_ctx, t, s);
   }
@@ -1614,13 +1643,13 @@ static void perform_transport_op(grpc_exec_ctx *exec_ctx, grpc_transport *gt,
 void grpc_chttp2_maybe_complete_recv_initial_metadata(grpc_exec_ctx *exec_ctx,
                                                       grpc_chttp2_transport *t,
                                                       grpc_chttp2_stream *s) {
-  grpc_byte_stream *bs;
   if (s->recv_initial_metadata_ready != NULL &&
       s->published_metadata[0] != GRPC_METADATA_NOT_PUBLISHED) {
     if (s->seen_error) {
-      while ((bs = grpc_chttp2_incoming_frame_queue_pop(&s->incoming_frames)) !=
-             NULL) {
-        incoming_byte_stream_destroy_locked(exec_ctx, bs, GRPC_ERROR_NONE);
+      grpc_slice_buffer_reset_and_unref_internal(exec_ctx, &s->frame_storage);
+      if (!s->pending_byte_stream) {
+        grpc_slice_buffer_reset_and_unref_internal(
+            exec_ctx, &s->unprocessed_incoming_frames_buffer);
       }
     }
     grpc_chttp2_incoming_metadata_buffer_publish(
@@ -1633,39 +1662,65 @@ void grpc_chttp2_maybe_complete_recv_initial_metadata(grpc_exec_ctx *exec_ctx,
 void grpc_chttp2_maybe_complete_recv_message(grpc_exec_ctx *exec_ctx,
                                              grpc_chttp2_transport *t,
                                              grpc_chttp2_stream *s) {
-  grpc_byte_stream *bs;
+  grpc_error *error = GRPC_ERROR_NONE;
   if (s->recv_message_ready != NULL) {
-    while (s->final_metadata_requested && s->seen_error &&
-           (bs = grpc_chttp2_incoming_frame_queue_pop(&s->incoming_frames)) !=
-               NULL) {
-      incoming_byte_stream_destroy_locked(exec_ctx, bs, GRPC_ERROR_NONE);
-    }
-    if (s->incoming_frames.head != NULL) {
-      *s->recv_message =
-          grpc_chttp2_incoming_frame_queue_pop(&s->incoming_frames);
-      GPR_ASSERT(*s->recv_message != NULL);
+    *s->recv_message = NULL;
+    if (s->final_metadata_requested && s->seen_error) {
+      grpc_slice_buffer_reset_and_unref_internal(exec_ctx, &s->frame_storage);
+      if (!s->pending_byte_stream) {
+        grpc_slice_buffer_reset_and_unref_internal(
+            exec_ctx, &s->unprocessed_incoming_frames_buffer);
+      }
+    }
+    if (!s->pending_byte_stream) {
+      while (s->unprocessed_incoming_frames_buffer.length > 0 ||
+             s->frame_storage.length > 0) {
+        if (s->unprocessed_incoming_frames_buffer.length == 0) {
+          grpc_slice_buffer_swap(&s->unprocessed_incoming_frames_buffer,
+                                 &s->frame_storage);
+        }
+        error = deframe_unprocessed_incoming_frames(
+            exec_ctx, &s->data_parser, s,
+            &s->unprocessed_incoming_frames_buffer, NULL, s->recv_message);
+        if (error != GRPC_ERROR_NONE) {
+          s->seen_error = true;
+          grpc_slice_buffer_reset_and_unref_internal(exec_ctx,
+                                                     &s->frame_storage);
+          grpc_slice_buffer_reset_and_unref_internal(
+              exec_ctx, &s->unprocessed_incoming_frames_buffer);
+          break;
+        } else if (*s->recv_message != NULL) {
+          break;
+        }
+      }
+    }
+    if (error == GRPC_ERROR_NONE && *s->recv_message != NULL) {
       null_then_run_closure(exec_ctx, &s->recv_message_ready, GRPC_ERROR_NONE);
     } else if (s->published_metadata[1] != GRPC_METADATA_NOT_PUBLISHED) {
       *s->recv_message = NULL;
       null_then_run_closure(exec_ctx, &s->recv_message_ready, GRPC_ERROR_NONE);
     }
+    GRPC_ERROR_UNREF(error);
   }
 }
 
 void grpc_chttp2_maybe_complete_recv_trailing_metadata(grpc_exec_ctx *exec_ctx,
                                                        grpc_chttp2_transport *t,
                                                        grpc_chttp2_stream *s) {
-  grpc_byte_stream *bs;
   grpc_chttp2_maybe_complete_recv_message(exec_ctx, t, s);
   if (s->recv_trailing_metadata_finished != NULL && s->read_closed &&
       s->write_closed) {
     if (s->seen_error) {
-      while ((bs = grpc_chttp2_incoming_frame_queue_pop(&s->incoming_frames)) !=
-             NULL) {
-        incoming_byte_stream_destroy_locked(exec_ctx, bs, GRPC_ERROR_NONE);
+      grpc_slice_buffer_reset_and_unref_internal(exec_ctx, &s->frame_storage);
+      if (!s->pending_byte_stream) {
+        grpc_slice_buffer_reset_and_unref_internal(
+            exec_ctx, &s->unprocessed_incoming_frames_buffer);
       }
     }
-    if (s->all_incoming_byte_streams_finished &&
+    bool pending_data = s->pending_byte_stream ||
+                        s->unprocessed_incoming_frames_buffer.length > 0;
+    if (s->read_closed && s->frame_storage.length == 0 &&
+        (!pending_data || s->seen_error) &&
         s->recv_trailing_metadata_finished != NULL) {
       grpc_chttp2_incoming_metadata_buffer_publish(
           exec_ctx, &s->metadata_buffer[1], s->recv_trailing_metadata);
@@ -1676,14 +1731,6 @@ void grpc_chttp2_maybe_complete_recv_trailing_metadata(grpc_exec_ctx *exec_ctx,
   }
 }
 
-static void decrement_active_streams_locked(grpc_exec_ctx *exec_ctx,
-                                            grpc_chttp2_transport *t,
-                                            grpc_chttp2_stream *s) {
-  if ((s->all_incoming_byte_streams_finished = gpr_unref(&s->active_streams))) {
-    grpc_chttp2_maybe_complete_recv_trailing_metadata(exec_ctx, t, s);
-  }
-}
-
 static void remove_stream(grpc_exec_ctx *exec_ctx, grpc_chttp2_transport *t,
                           uint32_t id, grpc_error *error) {
   grpc_chttp2_stream *s = grpc_chttp2_stream_map_delete(&t->stream_map, id);
@@ -1692,10 +1739,19 @@ static void remove_stream(grpc_exec_ctx *exec_ctx, grpc_chttp2_transport *t,
     t->incoming_stream = NULL;
     grpc_chttp2_parsing_become_skip_parser(exec_ctx, t);
   }
-  if (s->data_parser.parsing_frame != NULL) {
-    grpc_chttp2_incoming_byte_stream_finished(
-        exec_ctx, s->data_parser.parsing_frame, GRPC_ERROR_REF(error));
+  if (s->pending_byte_stream) {
+    if (s->on_next != NULL) {
+      grpc_chttp2_incoming_byte_stream *bs = s->data_parser.parsing_frame;
+      if (error == GRPC_ERROR_NONE) {
+        error = GRPC_ERROR_CREATE_FROM_STATIC_STRING("Truncated message");
+      }
+      incoming_byte_stream_publish_error(exec_ctx, bs, error);
+      incoming_byte_stream_unref(exec_ctx, bs);
       s->data_parser.parsing_frame = NULL;
+    } else {
+      GRPC_ERROR_UNREF(s->byte_stream_error);
+      s->byte_stream_error = GRPC_ERROR_REF(error);
+    }
   }
 
   if (grpc_chttp2_stream_map_size(&t->stream_map) == 0) {
@@ -1881,7 +1937,6 @@ void grpc_chttp2_mark_stream_closed(grpc_exec_ctx *exec_ctx,
         s->published_metadata[i] = GPRC_METADATA_PUBLISHED_AT_CLOSE;
       }
     }
-    decrement_active_streams_locked(exec_ctx, t, s);
     grpc_chttp2_maybe_complete_recv_initial_metadata(exec_ctx, t, s);
     grpc_chttp2_maybe_complete_recv_message(exec_ctx, t, s);
   }
@@ -2312,7 +2367,9 @@ static void init_keepalive_ping_locked(grpc_exec_ctx *exec_ctx, void *arg,
                                        grpc_error *error) {
   grpc_chttp2_transport *t = arg;
   GPR_ASSERT(t->keepalive_state == GRPC_CHTTP2_KEEPALIVE_STATE_WAITING);
-  if (error == GRPC_ERROR_NONE && !(t->destroying || t->closed)) {
+  if (t->destroying || t->closed) {
+    t->keepalive_state = GRPC_CHTTP2_KEEPALIVE_STATE_DYING;
+  } else if (error == GRPC_ERROR_NONE) {
     if (t->keepalive_permit_without_calls ||
         grpc_chttp2_stream_map_size(&t->stream_map) > 0) {
       t->keepalive_state = GRPC_CHTTP2_KEEPALIVE_STATE_PINGING;
@@ -2327,7 +2384,7 @@ static void init_keepalive_ping_locked(grpc_exec_ctx *exec_ctx, void *arg,
           gpr_time_add(gpr_now(GPR_CLOCK_MONOTONIC), t->keepalive_time),
           &t->init_keepalive_ping_locked, gpr_now(GPR_CLOCK_MONOTONIC));
     }
-  } else if (error == GRPC_ERROR_CANCELLED && !(t->destroying || t->closed)) {
+  } else if (error == GRPC_ERROR_CANCELLED) {
     /* The keepalive ping timer may be cancelled by bdp */
     GRPC_CHTTP2_REF_TRANSPORT(t, "init keepalive ping");
     grpc_timer_init(
@@ -2419,12 +2476,28 @@ static void set_pollset_set(grpc_exec_ctx *exec_ctx, grpc_transport *gt,
  * BYTE STREAM
  */
 
+static void reset_byte_stream(grpc_exec_ctx *exec_ctx, void *arg,
+                              grpc_error *error) {
+  grpc_chttp2_stream *s = (grpc_chttp2_stream *)arg;
+
+  s->pending_byte_stream = false;
+  if (error == GRPC_ERROR_NONE) {
+    grpc_chttp2_maybe_complete_recv_message(exec_ctx, s->t, s);
+    grpc_chttp2_maybe_complete_recv_trailing_metadata(exec_ctx, s->t, s);
+  } else {
+    GPR_ASSERT(error != GRPC_ERROR_NONE);
+    grpc_closure_sched(exec_ctx, s->on_next, GRPC_ERROR_REF(error));
+    s->on_next = NULL;
+    GRPC_ERROR_UNREF(s->byte_stream_error);
+    s->byte_stream_error = GRPC_ERROR_NONE;
+    grpc_chttp2_cancel_stream(exec_ctx, s->t, s, GRPC_ERROR_REF(error));
+    s->byte_stream_error = error;
+  }
+}
+
 static void incoming_byte_stream_unref(grpc_exec_ctx *exec_ctx,
                                        grpc_chttp2_incoming_byte_stream *bs) {
   if (gpr_unref(&bs->refs)) {
-    GRPC_ERROR_UNREF(bs->error);
-    grpc_slice_buffer_destroy_internal(exec_ctx, &bs->slices);
-    gpr_mu_destroy(&bs->slice_mu);
     gpr_free(bs);
   }
 }
@@ -2484,37 +2557,54 @@ static void incoming_byte_stream_next_locked(grpc_exec_ctx *exec_ctx,
   grpc_chttp2_transport *t = bs->transport;
   grpc_chttp2_stream *s = bs->stream;
 
-  if (bs->is_tail) {
-    gpr_mu_lock(&bs->slice_mu);
-    size_t cur_length = bs->slices.length;
-    gpr_mu_unlock(&bs->slice_mu);
+  size_t cur_length = s->frame_storage.length;
   incoming_byte_stream_update_flow_control(
       exec_ctx, t, s, bs->next_action.max_size_hint, cur_length);
+
+  GPR_ASSERT(s->unprocessed_incoming_frames_buffer.length == 0);
+  if (s->frame_storage.length > 0) {
+    grpc_slice_buffer_swap(&s->frame_storage,
+                           &s->unprocessed_incoming_frames_buffer);
+    grpc_closure_sched(exec_ctx, bs->next_action.on_complete, GRPC_ERROR_NONE);
+  } else if (s->byte_stream_error != GRPC_ERROR_NONE) {
+    grpc_closure_sched(exec_ctx, bs->next_action.on_complete,
+                       GRPC_ERROR_REF(s->byte_stream_error));
+    if (s->data_parser.parsing_frame != NULL) {
+      incoming_byte_stream_unref(exec_ctx, s->data_parser.parsing_frame);
+      s->data_parser.parsing_frame = NULL;
+    }
+  } else if (s->read_closed) {
+    if (bs->remaining_bytes != 0) {
+      s->byte_stream_error =
+          GRPC_ERROR_CREATE_FROM_STATIC_STRING("Truncated message");
+      grpc_closure_sched(exec_ctx, bs->next_action.on_complete,
+                         GRPC_ERROR_REF(s->byte_stream_error));
+      if (s->data_parser.parsing_frame != NULL) {
+        incoming_byte_stream_unref(exec_ctx, s->data_parser.parsing_frame);
+        s->data_parser.parsing_frame = NULL;
       }
-  gpr_mu_lock(&bs->slice_mu);
-  if (bs->slices.count > 0) {
-    *bs->next_action.slice = grpc_slice_buffer_take_first(&bs->slices);
-    grpc_closure_run(exec_ctx, bs->next_action.on_complete, GRPC_ERROR_NONE);
-  } else if (bs->error != GRPC_ERROR_NONE) {
-    grpc_closure_run(exec_ctx, bs->next_action.on_complete,
-                     GRPC_ERROR_REF(bs->error));
     } else {
-    bs->on_next = bs->next_action.on_complete;
-    bs->next = bs->next_action.slice;
+      /* Should never reach here. */
+      GPR_ASSERT(false);
+    }
+  } else {
+    s->on_next = bs->next_action.on_complete;
   }
-  gpr_mu_unlock(&bs->slice_mu);
   incoming_byte_stream_unref(exec_ctx, bs);
 }
 
-static int incoming_byte_stream_next(grpc_exec_ctx *exec_ctx,
+static bool incoming_byte_stream_next(grpc_exec_ctx *exec_ctx,
                                       grpc_byte_stream *byte_stream,
-                                     grpc_slice *slice, size_t max_size_hint,
+                                      size_t max_size_hint,
                                       grpc_closure *on_complete) {
   GPR_TIMER_BEGIN("incoming_byte_stream_next", 0);
   grpc_chttp2_incoming_byte_stream *bs =
       (grpc_chttp2_incoming_byte_stream *)byte_stream;
+  grpc_chttp2_stream *s = bs->stream;
+  if (s->unprocessed_incoming_frames_buffer.length > 0) {
+    return true;
+  } else {
     gpr_ref(&bs->refs);
-  bs->next_action.slice = slice;
     bs->next_action.max_size_hint = max_size_hint;
     bs->next_action.on_complete = on_complete;
     grpc_closure_sched(
@@ -2524,7 +2614,33 @@ static int incoming_byte_stream_next(grpc_exec_ctx *exec_ctx,
             grpc_combiner_scheduler(bs->transport->combiner, false)),
         GRPC_ERROR_NONE);
     GPR_TIMER_END("incoming_byte_stream_next", 0);
-  return 0;
+    return false;
+  }
+}
+
+static grpc_error *incoming_byte_stream_pull(grpc_exec_ctx *exec_ctx,
+                                             grpc_byte_stream *byte_stream,
+                                             grpc_slice *slice) {
+  GPR_TIMER_BEGIN("incoming_byte_stream_pull", 0);
+  grpc_chttp2_incoming_byte_stream *bs =
+      (grpc_chttp2_incoming_byte_stream *)byte_stream;
+  grpc_chttp2_stream *s = bs->stream;
+
+  if (s->unprocessed_incoming_frames_buffer.length > 0) {
+    grpc_error *error = deframe_unprocessed_incoming_frames(
+        exec_ctx, &s->data_parser, s, &s->unprocessed_incoming_frames_buffer,
+        slice, NULL);
+    if (error != GRPC_ERROR_NONE) {
+      return error;
+    }
+  } else {
+    grpc_error *error =
+        GRPC_ERROR_CREATE_FROM_STATIC_STRING("Truncated message");
+    grpc_closure_sched(exec_ctx, &s->reset_byte_stream, GRPC_ERROR_REF(error));
+    return error;
+  }
+  GPR_TIMER_END("incoming_byte_stream_pull", 0);
+  return GRPC_ERROR_NONE;
 }
 
 static void incoming_byte_stream_destroy(grpc_exec_ctx *exec_ctx,
@@ -2534,9 +2650,14 @@ static void incoming_byte_stream_destroy_locked(grpc_exec_ctx *exec_ctx,
                                                 void *byte_stream,
                                                 grpc_error *error_ignored) {
   grpc_chttp2_incoming_byte_stream *bs = byte_stream;
+  grpc_chttp2_stream *s = bs->stream;
+  grpc_chttp2_transport *t = s->t;
+
   GPR_ASSERT(bs->base.destroy == incoming_byte_stream_destroy);
-  decrement_active_streams_locked(exec_ctx, bs->transport, bs->stream);
   incoming_byte_stream_unref(exec_ctx, bs);
+  s->pending_byte_stream = false;
+  grpc_chttp2_maybe_complete_recv_message(exec_ctx, t, s);
+  grpc_chttp2_maybe_complete_recv_trailing_metadata(exec_ctx, t, s);
 }
 
 static void incoming_byte_stream_destroy(grpc_exec_ctx *exec_ctx,
@@ -2556,50 +2677,53 @@ static void incoming_byte_stream_destroy(grpc_exec_ctx *exec_ctx,
 static void incoming_byte_stream_publish_error(
     grpc_exec_ctx *exec_ctx, grpc_chttp2_incoming_byte_stream *bs,
     grpc_error *error) {
+  grpc_chttp2_stream *s = bs->stream;
+
   GPR_ASSERT(error != GRPC_ERROR_NONE);
-  grpc_closure_sched(exec_ctx, bs->on_next, GRPC_ERROR_REF(error));
-  bs->on_next = NULL;
-  GRPC_ERROR_UNREF(bs->error);
+  grpc_closure_sched(exec_ctx, s->on_next, GRPC_ERROR_REF(error));
+  s->on_next = NULL;
+  GRPC_ERROR_UNREF(s->byte_stream_error);
+  s->byte_stream_error = GRPC_ERROR_REF(error);
   grpc_chttp2_cancel_stream(exec_ctx, bs->transport, bs->stream,
                             GRPC_ERROR_REF(error));
-  bs->error = error;
 }
 
-void grpc_chttp2_incoming_byte_stream_push(grpc_exec_ctx *exec_ctx,
-                                           grpc_chttp2_incoming_byte_stream *bs,
-                                           grpc_slice slice) {
-  gpr_mu_lock(&bs->slice_mu);
+grpc_error *grpc_chttp2_incoming_byte_stream_push(
+    grpc_exec_ctx *exec_ctx, grpc_chttp2_incoming_byte_stream *bs,
+    grpc_slice slice, grpc_slice *slice_out) {
+  grpc_chttp2_stream *s = bs->stream;
+
   if (bs->remaining_bytes < GRPC_SLICE_LENGTH(slice)) {
-    incoming_byte_stream_publish_error(
-        exec_ctx, bs,
-        GRPC_ERROR_CREATE_FROM_STATIC_STRING("Too many bytes in stream"));
+    grpc_error *error =
+        GRPC_ERROR_CREATE_FROM_STATIC_STRING("Too many bytes in stream");
+
+    grpc_closure_sched(exec_ctx, &s->reset_byte_stream, GRPC_ERROR_REF(error));
+    grpc_slice_unref_internal(exec_ctx, slice);
+    return error;
   } else {
     bs->remaining_bytes -= (uint32_t)GRPC_SLICE_LENGTH(slice);
-    if (bs->on_next != NULL) {
-      *bs->next = slice;
-      grpc_closure_sched(exec_ctx, bs->on_next, GRPC_ERROR_NONE);
-      bs->on_next = NULL;
-    } else {
-      grpc_slice_buffer_add(&bs->slices, slice);
+    if (slice_out != NULL) {
+      *slice_out = slice;
     }
+    return GRPC_ERROR_NONE;
   }
-  gpr_mu_unlock(&bs->slice_mu);
 }
 
-void grpc_chttp2_incoming_byte_stream_finished(
+grpc_error *grpc_chttp2_incoming_byte_stream_finished(
     grpc_exec_ctx *exec_ctx, grpc_chttp2_incoming_byte_stream *bs,
-    grpc_error *error) {
+    grpc_error *error, bool reset_on_error) {
+  grpc_chttp2_stream *s = bs->stream;
+
   if (error == GRPC_ERROR_NONE) {
-    gpr_mu_lock(&bs->slice_mu);
     if (bs->remaining_bytes != 0) {
       error = GRPC_ERROR_CREATE_FROM_STATIC_STRING("Truncated message");
     }
-    gpr_mu_unlock(&bs->slice_mu);
   }
-  if (error != GRPC_ERROR_NONE) {
-    incoming_byte_stream_publish_error(exec_ctx, bs, error);
+  if (error != GRPC_ERROR_NONE && reset_on_error) {
+    grpc_closure_sched(exec_ctx, &s->reset_byte_stream, GRPC_ERROR_REF(error));
   }
   incoming_byte_stream_unref(exec_ctx, bs);
+  return error;
 }
 
 grpc_chttp2_incoming_byte_stream *grpc_chttp2_incoming_byte_stream_create(
@@ -2611,26 +2735,12 @@ grpc_chttp2_incoming_byte_stream *grpc_chttp2_incoming_byte_stream_create(
   incoming_byte_stream->remaining_bytes = frame_size;
   incoming_byte_stream->base.flags = flags;
   incoming_byte_stream->base.next = incoming_byte_stream_next;
+  incoming_byte_stream->base.pull = incoming_byte_stream_pull;
   incoming_byte_stream->base.destroy = incoming_byte_stream_destroy;
-  gpr_mu_init(&incoming_byte_stream->slice_mu);
   gpr_ref_init(&incoming_byte_stream->refs, 2);
-  incoming_byte_stream->next_message = NULL;
   incoming_byte_stream->transport = t;
   incoming_byte_stream->stream = s;
-  gpr_ref(&incoming_byte_stream->stream->active_streams);
-  grpc_slice_buffer_init(&incoming_byte_stream->slices);
-  incoming_byte_stream->on_next = NULL;
-  incoming_byte_stream->is_tail = 1;
-  incoming_byte_stream->error = GRPC_ERROR_NONE;
-  grpc_chttp2_incoming_frame_queue *q = &s->incoming_frames;
-  if (q->head == NULL) {
-    q->head = incoming_byte_stream;
-  } else {
-    q->tail->is_tail = 0;
-    q->tail->next_message = incoming_byte_stream;
-  }
-  q->tail = incoming_byte_stream;
-  grpc_chttp2_maybe_complete_recv_message(exec_ctx, t, s);
+  s->byte_stream_error = GRPC_ERROR_NONE;
   return incoming_byte_stream;
 }
 

src/core/ext/transport/chttp2/transport/frame_data.c

@@ -40,6 +40,7 @@
 #include <grpc/support/string_util.h>
 #include <grpc/support/useful.h>
 #include "src/core/ext/transport/chttp2/transport/internal.h"
+#include "src/core/lib/slice/slice_internal.h"
 #include "src/core/lib/slice/slice_string_helpers.h"
 #include "src/core/lib/support/string.h"
 #include "src/core/lib/transport/transport.h"
@@ -53,16 +54,17 @@ grpc_error *grpc_chttp2_data_parser_init(grpc_chttp2_data_parser *parser) {
 void grpc_chttp2_data_parser_destroy(grpc_exec_ctx *exec_ctx,
                                      grpc_chttp2_data_parser *parser) {
   if (parser->parsing_frame != NULL) {
-    grpc_chttp2_incoming_byte_stream_finished(
+    GRPC_ERROR_UNREF(grpc_chttp2_incoming_byte_stream_finished(
         exec_ctx, parser->parsing_frame,
-        GRPC_ERROR_CREATE_FROM_STATIC_STRING("Parser destroyed"));
+        GRPC_ERROR_CREATE_FROM_STATIC_STRING("Parser destroyed"), false));
   }
   GRPC_ERROR_UNREF(parser->error);
 }
 
 grpc_error *grpc_chttp2_data_parser_begin_frame(grpc_chttp2_data_parser *parser,
                                                 uint8_t flags,
-                                                uint32_t stream_id) {
+                                                uint32_t stream_id,
+                                                grpc_chttp2_stream *s) {
   if (flags & ~GRPC_CHTTP2_DATA_FLAG_END_STREAM) {
     char *msg;
     gpr_asprintf(&msg, "unsupported data flags: 0x%02x", flags);
@@ -74,47 +76,14 @@ grpc_error *grpc_chttp2_data_parser_begin_frame(grpc_chttp2_data_parser *parser,
   }
 
   if (flags & GRPC_CHTTP2_DATA_FLAG_END_STREAM) {
-    parser->is_last_frame = 1;
+    s->received_last_frame = true;
   } else {
-    parser->is_last_frame = 0;
+    s->received_last_frame = false;
   }
 
   return GRPC_ERROR_NONE;
 }
 
-void grpc_chttp2_incoming_frame_queue_merge(
-    grpc_chttp2_incoming_frame_queue *head_dst,
-    grpc_chttp2_incoming_frame_queue *tail_src) {
-  if (tail_src->head == NULL) {
-    return;
-  }
-
-  if (head_dst->head == NULL) {
-    *head_dst = *tail_src;
-    memset(tail_src, 0, sizeof(*tail_src));
-    return;
-  }
-
-  head_dst->tail->next_message = tail_src->head;
-  head_dst->tail = tail_src->tail;
-  memset(tail_src, 0, sizeof(*tail_src));
-}
-
-grpc_byte_stream *grpc_chttp2_incoming_frame_queue_pop(
-    grpc_chttp2_incoming_frame_queue *q) {
-  grpc_byte_stream *out;
-  if (q->head == NULL) {
-    return NULL;
-  }
-  out = &q->head->base;
-  if (q->head == q->tail) {
-    memset(q, 0, sizeof(*q));
-  } else {
-    q->head = q->head->next_message;
-  }
-  return out;
-}
-
 void grpc_chttp2_encode_data(uint32_t id, grpc_slice_buffer *inbuf,
                              uint32_t write_bytes, int is_eof,
                              grpc_transport_one_way_stats *stats,
@@ -143,35 +112,46 @@ void grpc_chttp2_encode_data(uint32_t id, grpc_slice_buffer *inbuf,
   stats->data_bytes += write_bytes;
 }
 
-static grpc_error *parse_inner(grpc_exec_ctx *exec_ctx,
+grpc_error *deframe_unprocessed_incoming_frames(grpc_exec_ctx *exec_ctx,
                                                 grpc_chttp2_data_parser *p,
-                               grpc_chttp2_transport *t, grpc_chttp2_stream *s,
-                               grpc_slice slice) {
-  uint8_t *const beg = GRPC_SLICE_START_PTR(slice);
-  uint8_t *const end = GRPC_SLICE_END_PTR(slice);
-  uint8_t *cur = beg;
+                                                grpc_chttp2_stream *s,
+                                                grpc_slice_buffer *slices,
+                                                grpc_slice *slice_out,
+                                                grpc_byte_stream **stream_out) {
+  grpc_error *error = GRPC_ERROR_NONE;
+  grpc_chttp2_transport *t = s->t;
+
+  while (slices->count > 0) {
+    uint8_t *beg = NULL;
+    uint8_t *end = NULL;
+    uint8_t *cur = NULL;
+
+    grpc_slice slice = grpc_slice_buffer_take_first(slices);
+
+    beg = GRPC_SLICE_START_PTR(slice);
+    end = GRPC_SLICE_END_PTR(slice);
+    cur = beg;
     uint32_t message_flags;
-  grpc_chttp2_incoming_byte_stream *incoming_byte_stream;
     char *msg;
 
     if (cur == end) {
-    return GRPC_ERROR_NONE;
+      grpc_slice_unref_internal(exec_ctx, slice);
+      continue;
     }
 
     switch (p->state) {
       case GRPC_CHTTP2_DATA_ERROR:
         p->state = GRPC_CHTTP2_DATA_ERROR;
+        grpc_slice_unref_internal(exec_ctx, slice);
         return GRPC_ERROR_REF(p->error);
-    fh_0:
       case GRPC_CHTTP2_DATA_FH_0:
-      s->stats.incoming.framing_bytes++;
         p->frame_type = *cur;
         switch (p->frame_type) {
           case 0:
-          p->is_frame_compressed = 0; /* GPR_FALSE */
+            p->is_frame_compressed = false; /* GPR_FALSE */
             break;
           case 1:
-          p->is_frame_compressed = 1; /* GPR_TRUE */
+            p->is_frame_compressed = true; /* GPR_TRUE */
             break;
           default:
             gpr_asprintf(&msg, "Bad GRPC frame type 0x%02x", p->frame_type);
@@ -186,39 +166,42 @@ static grpc_error *parse_inner(grpc_exec_ctx *exec_ctx,
             p->error =
                 grpc_error_set_int(p->error, GRPC_ERROR_INT_OFFSET, cur - beg);
             p->state = GRPC_CHTTP2_DATA_ERROR;
+            grpc_slice_unref_internal(exec_ctx, slice);
             return GRPC_ERROR_REF(p->error);
         }
         if (++cur == end) {
           p->state = GRPC_CHTTP2_DATA_FH_1;
-        return GRPC_ERROR_NONE;
+          grpc_slice_unref_internal(exec_ctx, slice);
+          continue;
         }
       /* fallthrough */
       case GRPC_CHTTP2_DATA_FH_1:
-      s->stats.incoming.framing_bytes++;
         p->frame_size = ((uint32_t)*cur) << 24;
         if (++cur == end) {
           p->state = GRPC_CHTTP2_DATA_FH_2;
-        return GRPC_ERROR_NONE;
+          grpc_slice_unref_internal(exec_ctx, slice);
+          continue;
         }
       /* fallthrough */
       case GRPC_CHTTP2_DATA_FH_2:
-      s->stats.incoming.framing_bytes++;
         p->frame_size |= ((uint32_t)*cur) << 16;
         if (++cur == end) {
           p->state = GRPC_CHTTP2_DATA_FH_3;
-        return GRPC_ERROR_NONE;
+          grpc_slice_unref_internal(exec_ctx, slice);
+          continue;
         }
       /* fallthrough */
       case GRPC_CHTTP2_DATA_FH_3:
-      s->stats.incoming.framing_bytes++;
         p->frame_size |= ((uint32_t)*cur) << 8;
         if (++cur == end) {
           p->state = GRPC_CHTTP2_DATA_FH_4;
-        return GRPC_ERROR_NONE;
+          grpc_slice_unref_internal(exec_ctx, slice);
+          continue;
         }
       /* fallthrough */
       case GRPC_CHTTP2_DATA_FH_4:
-      s->stats.incoming.framing_bytes++;
+        GPR_ASSERT(stream_out != NULL);
+        GPR_ASSERT(p->parsing_frame == NULL);
         p->frame_size |= ((uint32_t)*cur);
         p->state = GRPC_CHTTP2_DATA_FRAME;
         ++cur;
@@ -226,62 +209,120 @@ static grpc_error *parse_inner(grpc_exec_ctx *exec_ctx,
         if (p->is_frame_compressed) {
           message_flags |= GRPC_WRITE_INTERNAL_COMPRESS;
         }
-      p->parsing_frame = incoming_byte_stream =
-          grpc_chttp2_incoming_byte_stream_create(exec_ctx, t, s, p->frame_size,
-                                                  message_flags);
-    /* fallthrough */
-    case GRPC_CHTTP2_DATA_FRAME:
-      if (cur == end) {
+        p->parsing_frame = grpc_chttp2_incoming_byte_stream_create(
+            exec_ctx, t, s, p->frame_size, message_flags);
+        *stream_out = &p->parsing_frame->base;
+        if (p->parsing_frame->remaining_bytes == 0) {
+          GRPC_ERROR_UNREF(grpc_chttp2_incoming_byte_stream_finished(
+              exec_ctx, p->parsing_frame, GRPC_ERROR_NONE, true));
+          p->parsing_frame = NULL;
+          p->state = GRPC_CHTTP2_DATA_FH_0;
+        }
+        s->pending_byte_stream = true;
+
+        if (cur != end) {
+          grpc_slice_buffer_undo_take_first(
+              &s->unprocessed_incoming_frames_buffer,
+              grpc_slice_sub(slice, (size_t)(cur - beg), (size_t)(end - beg)));
+        }
+        grpc_slice_unref_internal(exec_ctx, slice);
         return GRPC_ERROR_NONE;
+      case GRPC_CHTTP2_DATA_FRAME: {
+        GPR_ASSERT(p->parsing_frame != NULL);
+        GPR_ASSERT(slice_out != NULL);
+        if (cur == end) {
+          grpc_slice_unref_internal(exec_ctx, slice);
+          continue;
         }
         uint32_t remaining = (uint32_t)(end - cur);
         if (remaining == p->frame_size) {
-        s->stats.incoming.data_bytes += p->frame_size;
-        grpc_chttp2_incoming_byte_stream_push(
+          if (GRPC_ERROR_NONE != (error = grpc_chttp2_incoming_byte_stream_push(
                                       exec_ctx, p->parsing_frame,
-            grpc_slice_sub(slice, (size_t)(cur - beg), (size_t)(end - beg)));
-        grpc_chttp2_incoming_byte_stream_finished(exec_ctx, p->parsing_frame,
-                                                  GRPC_ERROR_NONE);
+                                      grpc_slice_sub(slice, (size_t)(cur - beg),
+                                                     (size_t)(end - beg)),
+                                      slice_out))) {
+            grpc_slice_unref_internal(exec_ctx, slice);
+            return error;
+          }
+          if (GRPC_ERROR_NONE !=
+              (error = grpc_chttp2_incoming_byte_stream_finished(
+                   exec_ctx, p->parsing_frame, GRPC_ERROR_NONE, true))) {
+            grpc_slice_unref_internal(exec_ctx, slice);
+            return error;
+          }
           p->parsing_frame = NULL;
           p->state = GRPC_CHTTP2_DATA_FH_0;
+          grpc_slice_unref_internal(exec_ctx, slice);
           return GRPC_ERROR_NONE;
-      } else if (remaining > p->frame_size) {
-        s->stats.incoming.data_bytes += p->frame_size;
-        grpc_chttp2_incoming_byte_stream_push(
+        } else if (remaining < p->frame_size) {
+          if (GRPC_ERROR_NONE != (error = grpc_chttp2_incoming_byte_stream_push(
                                       exec_ctx, p->parsing_frame,
                                       grpc_slice_sub(slice, (size_t)(cur - beg),
-                           (size_t)(cur + p->frame_size - beg)));
-        grpc_chttp2_incoming_byte_stream_finished(exec_ctx, p->parsing_frame,
-                                                  GRPC_ERROR_NONE);
-        p->parsing_frame = NULL;
-        cur += p->frame_size;
-        goto fh_0; /* loop */
+                                                     (size_t)(end - beg)),
+                                      slice_out))) {
+            return error;
+          }
+          p->frame_size -= remaining;
+          grpc_slice_unref_internal(exec_ctx, slice);
+          return GRPC_ERROR_NONE;
         } else {
-        GPR_ASSERT(remaining <= p->frame_size);
-        grpc_chttp2_incoming_byte_stream_push(
+          GPR_ASSERT(remaining > p->frame_size);
+          if (GRPC_ERROR_NONE !=
+              (grpc_chttp2_incoming_byte_stream_push(
                   exec_ctx, p->parsing_frame,
+                  grpc_slice_sub(slice, (size_t)(cur - beg),
+                                 (size_t)(cur + p->frame_size - beg)),
+                  slice_out))) {
+            grpc_slice_unref_internal(exec_ctx, slice);
+            return error;
+          }
+          if (GRPC_ERROR_NONE !=
+              (error = grpc_chttp2_incoming_byte_stream_finished(
+                   exec_ctx, p->parsing_frame, GRPC_ERROR_NONE, true))) {
+            grpc_slice_unref_internal(exec_ctx, slice);
+            return error;
+          }
+          p->parsing_frame = NULL;
+          p->state = GRPC_CHTTP2_DATA_FH_0;
+          cur += p->frame_size;
+          grpc_slice_buffer_undo_take_first(
+              &s->unprocessed_incoming_frames_buffer,
               grpc_slice_sub(slice, (size_t)(cur - beg), (size_t)(end - beg)));
-        p->frame_size -= remaining;
-        s->stats.incoming.data_bytes += remaining;
+          grpc_slice_unref_internal(exec_ctx, slice);
           return GRPC_ERROR_NONE;
         }
       }
+    }
+  }
 
-  GPR_UNREACHABLE_CODE(
-      return GRPC_ERROR_CREATE_FROM_STATIC_STRING("Should never reach here"));
+  return GRPC_ERROR_NONE;
 }
 
 grpc_error *grpc_chttp2_data_parser_parse(grpc_exec_ctx *exec_ctx, void *parser,
                                           grpc_chttp2_transport *t,
                                           grpc_chttp2_stream *s,
                                           grpc_slice slice, int is_last) {
-  grpc_chttp2_data_parser *p = parser;
-  grpc_error *error = parse_inner(exec_ctx, p, t, s, slice);
+  /* grpc_error *error = parse_inner_buffer(exec_ctx, p, t, s, slice); */
+  s->stats.incoming.framing_bytes += GRPC_SLICE_LENGTH(slice);
+  if (!s->pending_byte_stream) {
+    grpc_slice_ref_internal(slice);
+    grpc_slice_buffer_add(&s->frame_storage, slice);
+    grpc_chttp2_maybe_complete_recv_message(exec_ctx, t, s);
+  } else if (s->on_next) {
+    GPR_ASSERT(s->frame_storage.length == 0);
+    grpc_slice_ref_internal(slice);
+    grpc_slice_buffer_add(&s->unprocessed_incoming_frames_buffer, slice);
+    grpc_closure_sched(exec_ctx, s->on_next, GRPC_ERROR_NONE);
+    s->on_next = NULL;
+  } else {
+    grpc_slice_ref_internal(slice);
+    grpc_slice_buffer_add(&s->frame_storage, slice);
+  }
 
-  if (is_last && p->is_last_frame) {
+  if (is_last && s->received_last_frame) {
     grpc_chttp2_mark_stream_closed(exec_ctx, t, s, true, false,
                                    GRPC_ERROR_NONE);
   }
 
-  return error;
+  return GRPC_ERROR_NONE;
 }

src/core/ext/transport/chttp2/transport/frame_data.h

@@ -56,28 +56,16 @@ typedef enum {
 typedef struct grpc_chttp2_incoming_byte_stream
     grpc_chttp2_incoming_byte_stream;
 
-typedef struct grpc_chttp2_incoming_frame_queue {
-  grpc_chttp2_incoming_byte_stream *head;
-  grpc_chttp2_incoming_byte_stream *tail;
-} grpc_chttp2_incoming_frame_queue;
-
 typedef struct {
   grpc_chttp2_stream_state state;
-  uint8_t is_last_frame;
   uint8_t frame_type;
   uint32_t frame_size;
   grpc_error *error;
 
-  int is_frame_compressed;
+  bool is_frame_compressed;
   grpc_chttp2_incoming_byte_stream *parsing_frame;
 } grpc_chttp2_data_parser;
 
-void grpc_chttp2_incoming_frame_queue_merge(
-    grpc_chttp2_incoming_frame_queue *head_dst,
-    grpc_chttp2_incoming_frame_queue *tail_src);
-grpc_byte_stream *grpc_chttp2_incoming_frame_queue_pop(
-    grpc_chttp2_incoming_frame_queue *q);
-
 /* initialize per-stream state for data frame parsing */
 grpc_error *grpc_chttp2_data_parser_init(grpc_chttp2_data_parser *parser);
 
@@ -87,7 +75,8 @@ void grpc_chttp2_data_parser_destroy(grpc_exec_ctx *exec_ctx,
 /* start processing a new data frame */
 grpc_error *grpc_chttp2_data_parser_begin_frame(grpc_chttp2_data_parser *parser,
                                                 uint8_t flags,
-                                                uint32_t stream_id);
+                                                uint32_t stream_id,
+                                                grpc_chttp2_stream *s);
 
 /* handle a slice of a data frame - is_last indicates the last slice of a
    frame */
@@ -101,4 +90,11 @@ void grpc_chttp2_encode_data(uint32_t id, grpc_slice_buffer *inbuf,
                              grpc_transport_one_way_stats *stats,
                              grpc_slice_buffer *outbuf);
 
+grpc_error *deframe_unprocessed_incoming_frames(grpc_exec_ctx *exec_ctx,
+                                                grpc_chttp2_data_parser *p,
+                                                grpc_chttp2_stream *s,
+                                                grpc_slice_buffer *slices,
+                                                grpc_slice *slice_out,
+                                                grpc_byte_stream **stream_out);
+
 #endif /* GRPC_CORE_EXT_TRANSPORT_CHTTP2_TRANSPORT_FRAME_DATA_H */

src/core/ext/transport/chttp2/transport/internal.h

@@ -195,22 +195,20 @@ typedef struct grpc_chttp2_write_cb {
 struct grpc_chttp2_incoming_byte_stream {
   grpc_byte_stream base;
   gpr_refcount refs;
-  struct grpc_chttp2_incoming_byte_stream *next_message;
-  grpc_error *error;
 
-  grpc_chttp2_transport *transport;
-  grpc_chttp2_stream *stream;
-  bool is_tail;
+  grpc_chttp2_transport *transport; /* immutable */
+  grpc_chttp2_stream *stream;       /* immutable */
 
-  gpr_mu slice_mu;  // protects slices, on_next
-  grpc_slice_buffer slices;
-  grpc_closure *on_next;
-  grpc_slice *next;
+  /* Accessed only by transport thread when stream->pending_byte_stream == false
+   * Accessed only by application thread when stream->pending_byte_stream ==
+   * true */
   uint32_t remaining_bytes;
 
+  /* Accessed only by transport thread when stream->pending_byte_stream == false
+   * Accessed only by application thread when stream->pending_byte_stream ==
+   * true */
   struct {
     grpc_closure closure;
-    grpc_slice *slice;
     size_t max_size_hint;
     grpc_closure *on_complete;
   } next_action;
@@ -222,6 +220,7 @@ typedef enum {
   GRPC_CHTTP2_KEEPALIVE_STATE_WAITING,
   GRPC_CHTTP2_KEEPALIVE_STATE_PINGING,
   GRPC_CHTTP2_KEEPALIVE_STATE_DYING,
+  GRPC_CHTTP2_KEEPALIVE_STATE_DISABLED,
 } grpc_chttp2_keepalive_state;
 
 struct grpc_chttp2_transport {
@@ -473,9 +472,6 @@ struct grpc_chttp2_stream {
   grpc_transport_stream_stats *collecting_stats;
   grpc_transport_stream_stats stats;
 
-  /** number of streams that are currently being read */
-  gpr_refcount active_streams;
-
   /** Is this stream closed for writing. */
   bool write_closed;
   /** Is this stream reading half-closed. */
@@ -499,7 +495,17 @@ struct grpc_chttp2_stream {
 
   grpc_chttp2_incoming_metadata_buffer metadata_buffer[2];
 
-  grpc_chttp2_incoming_frame_queue incoming_frames;
+  grpc_slice_buffer frame_storage; /* protected by t combiner */
+
+  /* Accessed only by transport thread when stream->pending_byte_stream == false
+   * Accessed only by application thread when stream->pending_byte_stream ==
+   * true */
+  grpc_slice_buffer unprocessed_incoming_frames_buffer;
+  grpc_closure *on_next;    /* protected by t combiner */
+  bool pending_byte_stream; /* protected by t combiner */
+  grpc_closure reset_byte_stream;
+  grpc_error *byte_stream_error; /* protected by t combiner */
+  bool received_last_frame;      /* protected by t combiner */
 
   gpr_timespec deadline;
 
@@ -512,6 +518,9 @@ struct grpc_chttp2_stream {
    * incoming_window = incoming_window_delta + transport.initial_window_size */
   int64_t incoming_window_delta;
   /** parsing state for data frames */
+  /* Accessed only by transport thread when stream->pending_byte_stream == false
+   * Accessed only by application thread when stream->pending_byte_stream ==
+   * true */
   grpc_chttp2_data_parser data_parser;
   /** number of bytes received - reset at end of parse thread execution */
   int64_t received_bytes;
@@ -790,10 +799,13 @@ void grpc_chttp2_ref_transport(grpc_chttp2_transport *t);
 grpc_chttp2_incoming_byte_stream *grpc_chttp2_incoming_byte_stream_create(
     grpc_exec_ctx *exec_ctx, grpc_chttp2_transport *t, grpc_chttp2_stream *s,
     uint32_t frame_size, uint32_t flags);
-void grpc_chttp2_incoming_byte_stream_push(grpc_exec_ctx *exec_ctx,
-                                           grpc_chttp2_incoming_byte_stream *bs,
-                                           grpc_slice slice);
-void grpc_chttp2_incoming_byte_stream_finished(
+grpc_error *grpc_chttp2_incoming_byte_stream_push(
+    grpc_exec_ctx *exec_ctx, grpc_chttp2_incoming_byte_stream *bs,
+    grpc_slice slice, grpc_slice *slice_out);
+grpc_error *grpc_chttp2_incoming_byte_stream_finished(
+    grpc_exec_ctx *exec_ctx, grpc_chttp2_incoming_byte_stream *bs,
+    grpc_error *error, bool reset_on_error);
+void grpc_chttp2_incoming_byte_stream_notify(
     grpc_exec_ctx *exec_ctx, grpc_chttp2_incoming_byte_stream *bs,
     grpc_error *error);
 

src/core/ext/transport/chttp2/transport/parsing.c

@@ -458,12 +458,13 @@ static grpc_error *init_data_frame_parser(grpc_exec_ctx *exec_ctx,
     return init_skip_frame_parser(exec_ctx, t, 0);
   }
   if (err == GRPC_ERROR_NONE) {
-    err = grpc_chttp2_data_parser_begin_frame(&s->data_parser,
-                                              t->incoming_frame_flags, s->id);
+    err = grpc_chttp2_data_parser_begin_frame(
+        &s->data_parser, t->incoming_frame_flags, s->id, s);
   }
 error_handler:
   if (err == GRPC_ERROR_NONE) {
     t->incoming_stream = s;
+    /* t->parser = grpc_chttp2_data_parser_parse;*/
     t->parser = grpc_chttp2_data_parser_parse;
     t->parser_data = &s->data_parser;
     return GRPC_ERROR_NONE;

src/core/ext/transport/chttp2/transport/writing.c

@@ -224,9 +224,9 @@ bool grpc_chttp2_begin_write(grpc_exec_ctx *exec_ctx,
           .is_eof = false,
           .use_true_binary_metadata =
               t->settings
-                  [GRPC_ACKED_SETTINGS]
+                  [GRPC_PEER_SETTINGS]
                   [GRPC_CHTTP2_SETTINGS_GRPC_ALLOW_TRUE_BINARY_METADATA] != 0,
-          .max_frame_size = t->settings[GRPC_ACKED_SETTINGS]
+          .max_frame_size = t->settings[GRPC_PEER_SETTINGS]
                                        [GRPC_CHTTP2_SETTINGS_MAX_FRAME_SIZE],
           .stats = &s->stats.outgoing};
       grpc_chttp2_encode_header(exec_ctx, &t->hpack_compressor,
@@ -267,7 +267,7 @@ bool grpc_chttp2_begin_write(grpc_exec_ctx *exec_ctx,
                 (int64_t)t->settings[GRPC_PEER_SETTINGS]
                                     [GRPC_CHTTP2_SETTINGS_INITIAL_WINDOW_SIZE]);
         uint32_t max_outgoing = (uint32_t)GPR_MIN(
-            t->settings[GRPC_ACKED_SETTINGS]
+            t->settings[GRPC_PEER_SETTINGS]
                        [GRPC_CHTTP2_SETTINGS_MAX_FRAME_SIZE],
             GPR_MIN(stream_outgoing_window, t->outgoing_window));
         if (max_outgoing > 0) {
@@ -328,11 +328,11 @@ bool grpc_chttp2_begin_write(grpc_exec_ctx *exec_ctx,
               .is_eof = true,
               .use_true_binary_metadata =
                   t->settings
-                      [GRPC_ACKED_SETTINGS]
+                      [GRPC_PEER_SETTINGS]
                       [GRPC_CHTTP2_SETTINGS_GRPC_ALLOW_TRUE_BINARY_METADATA] !=
                   0,
               .max_frame_size =
-                  t->settings[GRPC_ACKED_SETTINGS]
+                  t->settings[GRPC_PEER_SETTINGS]
                              [GRPC_CHTTP2_SETTINGS_MAX_FRAME_SIZE],
               .stats = &s->stats.outgoing};
           grpc_chttp2_encode_header(exec_ctx, &t->hpack_compressor,

src/core/ext/transport/cronet/transport/cronet_transport.c

@@ -973,9 +973,20 @@ static enum e_op_result execute_stream_op(grpc_exec_ctx *exec_ctx,
       grpc_slice_buffer write_slice_buffer;
       grpc_slice slice;
       grpc_slice_buffer_init(&write_slice_buffer);
-      grpc_byte_stream_next(
-          NULL, stream_op->payload->send_message.send_message, &slice,
-          stream_op->payload->send_message.send_message->length, NULL);
+      if (1 != grpc_byte_stream_next(
+                   exec_ctx, stream_op->payload->send_message.send_message,
+                   stream_op->payload->send_message.send_message->length,
+                   NULL)) {
+        /* Should never reach here */
+        GPR_ASSERT(false);
+      }
+      if (GRPC_ERROR_NONE !=
+          grpc_byte_stream_pull(exec_ctx,
+                                stream_op->payload->send_message.send_message,
+                                &slice)) {
+        /* Should never reach here */
+        GPR_ASSERT(false);
+      }
       grpc_slice_buffer_add(&write_slice_buffer, slice);
       if (write_slice_buffer.count != 1) {
         /* Empty request not handled yet */

src/core/lib/channel/channel_args.c

@@ -31,17 +31,18 @@
  *
  */
 
-#include "src/core/lib/channel/channel_args.h"
-#include <grpc/grpc.h>
-#include "src/core/lib/support/string.h"
+#include <limits.h>
+#include <string.h>
 
 #include <grpc/compression.h>
+#include <grpc/grpc.h>
 #include <grpc/support/alloc.h>
 #include <grpc/support/log.h>
 #include <grpc/support/string_util.h>
 #include <grpc/support/useful.h>
 
-#include <string.h>
+#include "src/core/lib/channel/channel_args.h"
+#include "src/core/lib/support/string.h"
 
 static grpc_arg copy_arg(const grpc_arg *src) {
   grpc_arg dst;
@@ -330,7 +331,7 @@ const grpc_arg *grpc_channel_args_find(const grpc_channel_args *args,
 }
 
 int grpc_channel_arg_get_integer(const grpc_arg *arg,
-                                 grpc_integer_options options) {
+                                 const grpc_integer_options options) {
   if (arg == NULL) return options.default_value;
   if (arg->type != GRPC_ARG_INTEGER) {
     gpr_log(GPR_ERROR, "%s ignored: it must be an integer", arg->key);

src/core/lib/channel/channel_args.h

@@ -120,9 +120,10 @@ typedef struct grpc_integer_options {
   int min_value;
   int max_value;
 } grpc_integer_options;
+
 /** Returns the value of \a arg, subject to the contraints in \a options. */
 int grpc_channel_arg_get_integer(const grpc_arg *arg,
-                                 grpc_integer_options options);
+                                 const grpc_integer_options options);
 
 bool grpc_channel_arg_get_bool(const grpc_arg *arg, bool default_value);
 

src/core/lib/channel/context.h

@@ -50,9 +50,6 @@ typedef enum {
   /// Reserved for traffic_class_context.
   GRPC_CONTEXT_TRAFFIC,
 
-  /// Costs for Load Reporting.
-  GRPC_CONTEXT_LR_COST,
-
   GRPC_CONTEXT_COUNT
 } grpc_context_index;
 

src/core/lib/iomgr/udp_server.c

@@ -79,10 +79,15 @@ struct grpc_udp_listener {
   grpc_resolved_address addr;
   grpc_closure read_closure;
   grpc_closure write_closure;
+  // To be called when corresponding QuicGrpcServer closes all active
+  // connections.
+  grpc_closure orphan_fd_closure;
   grpc_closure destroyed_closure;
   grpc_udp_server_read_cb read_cb;
   grpc_udp_server_write_cb write_cb;
   grpc_udp_server_orphan_cb orphan_cb;
+  // True if orphan_cb is trigered.
+  bool orphan_notified;
 
   struct grpc_udp_listener *next;
 };
@@ -146,6 +151,14 @@ grpc_udp_server *grpc_udp_server_create(const grpc_channel_args *args) {
   return s;
 }
 
+static void shutdown_fd(grpc_exec_ctx *exec_ctx, void *fd, grpc_error *error) {
+  grpc_fd_shutdown(exec_ctx, (grpc_fd *)fd, GRPC_ERROR_REF(error));
+}
+
+static void dummy_cb(grpc_exec_ctx *exec_ctx, void *arg, grpc_error *error) {
+  // No-op.
+}
+
 static void finish_shutdown(grpc_exec_ctx *exec_ctx, grpc_udp_server *s) {
   if (s->shutdown_complete != NULL) {
     grpc_closure_sched(exec_ctx, s->shutdown_complete, GRPC_ERROR_NONE);
@@ -195,12 +208,16 @@ static void deactivated_all_ports(grpc_exec_ctx *exec_ctx, grpc_udp_server *s) {
 
       grpc_closure_init(&sp->destroyed_closure, destroyed_port, s,
                         grpc_schedule_on_exec_ctx);
-
+      if (!sp->orphan_notified) {
         /* Call the orphan_cb to signal that the FD is about to be closed and
-       * should no longer be used. */
+         * should no longer be used. Because at this point, all listening ports
+         * have been shutdown already, no need to shutdown again.*/
+        grpc_closure_init(&sp->orphan_fd_closure, dummy_cb, sp->emfd,
+                          grpc_schedule_on_exec_ctx);
         GPR_ASSERT(sp->orphan_cb);
-      sp->orphan_cb(exec_ctx, sp->emfd, sp->server->user_data);
-
+        sp->orphan_cb(exec_ctx, sp->emfd, &sp->orphan_fd_closure,
+                      sp->server->user_data);
+      }
       grpc_fd_orphan(exec_ctx, sp->emfd, &sp->destroyed_closure, NULL,
                      "udp_listener_shutdown");
     }
@@ -225,9 +242,11 @@ void grpc_udp_server_destroy(grpc_exec_ctx *exec_ctx, grpc_udp_server *s,
   if (s->active_ports) {
     for (sp = s->head; sp; sp = sp->next) {
       GPR_ASSERT(sp->orphan_cb);
-      sp->orphan_cb(exec_ctx, sp->emfd, sp->server->user_data);
-      grpc_fd_shutdown(exec_ctx, sp->emfd, GRPC_ERROR_CREATE_FROM_STATIC_STRING(
-                                               "Server destroyed"));
+      grpc_closure_init(&sp->orphan_fd_closure, shutdown_fd, sp->emfd,
+                        grpc_schedule_on_exec_ctx);
+      sp->orphan_cb(exec_ctx, sp->emfd, &sp->orphan_fd_closure,
+                    sp->server->user_data);
+      sp->orphan_notified = true;
     }
     gpr_mu_unlock(&s->mu);
   } else {
@@ -391,6 +410,7 @@ static int add_socket_to_server(grpc_udp_server *s, int fd,
     sp->read_cb = read_cb;
     sp->write_cb = write_cb;
     sp->orphan_cb = orphan_cb;
+    sp->orphan_notified = false;
     GPR_ASSERT(sp->emfd);
     gpr_mu_unlock(&s->mu);
     gpr_free(name);

src/core/lib/iomgr/udp_server.h

@@ -55,7 +55,9 @@ typedef void (*grpc_udp_server_write_cb)(grpc_exec_ctx *exec_ctx, grpc_fd *emfd,
 
 /* Called when the grpc_fd is about to be orphaned (and the FD closed). */
 typedef void (*grpc_udp_server_orphan_cb)(grpc_exec_ctx *exec_ctx,
-                                          grpc_fd *emfd, void *user_data);
+                                          grpc_fd *emfd,
+                                          grpc_closure *shutdown_fd_callback,
+                                          void *user_data);
 
 /* Create a server, initially not bound to any ports */
 grpc_udp_server *grpc_udp_server_create(const grpc_channel_args *args);

src/core/lib/security/credentials/fake/fake_credentials.c

@@ -39,11 +39,15 @@
 #include <grpc/support/log.h>
 #include <grpc/support/string_util.h>
 
+#include "src/core/lib/channel/channel_args.h"
 #include "src/core/lib/iomgr/executor.h"
 #include "src/core/lib/support/string.h"
 
 /* -- Fake transport security credentials. -- */
 
+#define GRPC_ARG_FAKE_SECURITY_EXPECTED_TARGETS \
+  "grpc.fake_security.expected_targets"
+
 static grpc_security_status fake_transport_security_create_security_connector(
     grpc_exec_ctx *exec_ctx, grpc_channel_credentials *c,
     grpc_call_credentials *call_creds, const char *target,
@@ -88,6 +92,25 @@ grpc_server_credentials *grpc_fake_transport_security_server_credentials_create(
   return c;
 }
 
+grpc_arg grpc_fake_transport_expected_targets_arg(char *expected_targets) {
+  grpc_arg arg;
+  arg.type = GRPC_ARG_STRING;
+  arg.key = GRPC_ARG_FAKE_SECURITY_EXPECTED_TARGETS;
+  arg.value.string = expected_targets;
+  return arg;
+}
+
+const char *grpc_fake_transport_get_expected_targets(
+    const grpc_channel_args *args) {
+  const grpc_arg *expected_target_arg =
+      grpc_channel_args_find(args, GRPC_ARG_FAKE_SECURITY_EXPECTED_TARGETS);
+  if (expected_target_arg != NULL &&
+      expected_target_arg->type == GRPC_ARG_STRING) {
+    return expected_target_arg->value.string;
+  }
+  return NULL;
+}
+
 /* -- Metadata-only test credentials. -- */
 
 static void md_only_test_destruct(grpc_exec_ctx *exec_ctx,

src/core/lib/security/credentials/fake/fake_credentials.h

@@ -38,10 +38,17 @@
 
 /* -- Fake transport security credentials. -- */
 
+/* Creates a fake transport security credentials object for testing. */
+grpc_channel_credentials *grpc_fake_transport_security_credentials_create(void);
+
+/* Creates a fake server transport security credentials object for testing. */
+grpc_server_credentials *grpc_fake_transport_security_server_credentials_create(
+    void);
+
 /* Used to verify the target names given to the fake transport security
  * connector.
  *
- * Its syntax by example:
+ * The syntax of \a expected_targets by example:
  * For LB channels:
  *     "backend_target_1,backend_target_2,...;lb_target_1,lb_target_2,..."
  * For regular channels:
@@ -50,15 +57,11 @@
  * That is to say, LB channels have a heading list of LB targets separated from
  * the list of backend targets by a semicolon. For non-LB channels, only the
  * latter is present. */
-#define GRPC_ARG_FAKE_SECURITY_EXPECTED_TARGETS \
-  "grpc.test_only.fake_security.expected_target"
+grpc_arg grpc_fake_transport_expected_targets_arg(char *expected_targets);
 
-/* Creates a fake transport security credentials object for testing. */
-grpc_channel_credentials *grpc_fake_transport_security_credentials_create(void);
-
-/* Creates a fake server transport security credentials object for testing. */
-grpc_server_credentials *grpc_fake_transport_security_server_credentials_create(
-    void);
+/* Return the value associated with the expected targets channel arg or NULL */
+const char *grpc_fake_transport_get_expected_targets(
+    const grpc_channel_args *args);
 
 /* --  Metadata-only Test credentials. -- */
 

src/core/lib/security/transport/security_connector.c

@@ -423,12 +423,8 @@ grpc_channel_security_connector *grpc_fake_channel_security_connector_create(
   c->base.check_call_host = fake_channel_check_call_host;
   c->base.add_handshakers = fake_channel_add_handshakers;
   c->target = gpr_strdup(target);
-  const grpc_arg *expected_target_arg =
-      grpc_channel_args_find(args, GRPC_ARG_FAKE_SECURITY_EXPECTED_TARGETS);
-  if (expected_target_arg != NULL) {
-    GPR_ASSERT(expected_target_arg->type == GRPC_ARG_STRING);
-    c->expected_targets = gpr_strdup(expected_target_arg->value.string);
-  }
+  const char *expected_targets = grpc_fake_transport_get_expected_targets(args);
+  c->expected_targets = gpr_strdup(expected_targets);
   c->is_lb_channel = (grpc_lb_targets_info_find_in_args(args) != NULL);
   return &c->base;
 }

src/core/lib/surface/call.c

@@ -1187,6 +1187,7 @@ static void finish_batch_step(grpc_exec_ctx *exec_ctx, batch_control *bctl) {
 
 static void continue_receiving_slices(grpc_exec_ctx *exec_ctx,
                                       batch_control *bctl) {
+  grpc_error *error;
   grpc_call *call = bctl->call;
   for (;;) {
     size_t remaining = call->receiving_stream->length -
@@ -1198,11 +1199,22 @@ static void continue_receiving_slices(grpc_exec_ctx *exec_ctx,
       finish_batch_step(exec_ctx, bctl);
       return;
     }
-    if (grpc_byte_stream_next(exec_ctx, call->receiving_stream,
-                              &call->receiving_slice, remaining,
+    if (grpc_byte_stream_next(exec_ctx, call->receiving_stream, remaining,
                               &call->receiving_slice_ready)) {
+      error = grpc_byte_stream_pull(exec_ctx, call->receiving_stream,
+                                    &call->receiving_slice);
+      if (error == GRPC_ERROR_NONE) {
         grpc_slice_buffer_add(&(*call->receiving_buffer)->data.raw.slice_buffer,
                               call->receiving_slice);
+      } else {
+        grpc_byte_stream_destroy(exec_ctx, call->receiving_stream);
+        call->receiving_stream = NULL;
+        grpc_byte_buffer_destroy(*call->receiving_buffer);
+        *call->receiving_buffer = NULL;
+        call->receiving_message = 0;
+        finish_batch_step(exec_ctx, bctl);
+        return;
+      }
     } else {
       return;
     }
@@ -1213,12 +1225,24 @@ static void receiving_slice_ready(grpc_exec_ctx *exec_ctx, void *bctlp,
                                   grpc_error *error) {
   batch_control *bctl = bctlp;
   grpc_call *call = bctl->call;
+  grpc_byte_stream *bs = call->receiving_stream;
+  bool release_error = false;
 
+  if (error == GRPC_ERROR_NONE) {
+    grpc_slice slice;
+    error = grpc_byte_stream_pull(exec_ctx, bs, &slice);
     if (error == GRPC_ERROR_NONE) {
       grpc_slice_buffer_add(&(*call->receiving_buffer)->data.raw.slice_buffer,
-                          call->receiving_slice);
+                            slice);
       continue_receiving_slices(exec_ctx, bctl);
     } else {
+      /* Error returned by grpc_byte_stream_pull needs to be released manually
+       */
+      release_error = true;
+    }
+  }
+
+  if (error != GRPC_ERROR_NONE) {
     if (grpc_trace_operation_failures) {
       GRPC_LOG_IF_ERROR("receiving_slice_ready", GRPC_ERROR_REF(error));
     }
@@ -1226,7 +1250,11 @@ static void receiving_slice_ready(grpc_exec_ctx *exec_ctx, void *bctlp,
     call->receiving_stream = NULL;
     grpc_byte_buffer_destroy(*call->receiving_buffer);
     *call->receiving_buffer = NULL;
+    call->receiving_message = 0;
     finish_batch_step(exec_ctx, bctl);
+    if (release_error) {
+      GRPC_ERROR_UNREF(error);
+    }
   }
 }
 

src/core/lib/surface/server.c

@@ -44,6 +44,7 @@
 
 #include "src/core/lib/channel/channel_args.h"
 #include "src/core/lib/channel/connected_channel.h"
+#include "src/core/lib/iomgr/executor.h"
 #include "src/core/lib/iomgr/iomgr.h"
 #include "src/core/lib/slice/slice_internal.h"
 #include "src/core/lib/support/stack_lockfree.h"
@@ -211,6 +212,11 @@ struct grpc_server {
   gpr_mu mu_global; /* mutex for server and channel state */
   gpr_mu mu_call;   /* mutex for call-specific state */
 
+  /* startup synchronization: flag is protected by mu_global, signals whether
+     we are doing the listener start routine or not */
+  bool starting;
+  gpr_cv starting_cv;
+
   registered_method *registered_methods;
   /** one request matcher for unregistered methods */
   request_matcher unregistered_request_matcher;
@@ -388,6 +394,7 @@ static void server_delete(grpc_exec_ctx *exec_ctx, grpc_server *server) {
   grpc_channel_args_destroy(exec_ctx, server->channel_args);
   gpr_mu_destroy(&server->mu_global);
   gpr_mu_destroy(&server->mu_call);
+  gpr_cv_destroy(&server->starting_cv);
   while ((rm = server->registered_methods) != NULL) {
     server->registered_methods = rm->next;
     if (server->started) {
@@ -1030,6 +1037,7 @@ grpc_server *grpc_server_create(const grpc_channel_args *args, void *reserved) {
 
   gpr_mu_init(&server->mu_global);
   gpr_mu_init(&server->mu_call);
+  gpr_cv_init(&server->starting_cv);
 
   /* decremented by grpc_server_destroy */
   gpr_ref_init(&server->internal_refcount, 1);
@@ -1086,8 +1094,22 @@ void *grpc_server_register_method(
   return m;
 }
 
+static void start_listeners(grpc_exec_ctx *exec_ctx, void *s,
+                            grpc_error *error) {
+  grpc_server *server = s;
+  for (listener *l = server->listeners; l; l = l->next) {
+    l->start(exec_ctx, server, l->arg, server->pollsets, server->pollset_count);
+  }
+
+  gpr_mu_lock(&server->mu_global);
+  server->starting = false;
+  gpr_cv_signal(&server->starting_cv);
+  gpr_mu_unlock(&server->mu_global);
+
+  server_unref(exec_ctx, server);
+}
+
 void grpc_server_start(grpc_server *server) {
-  listener *l;
   size_t i;
   grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
 
@@ -1121,10 +1143,11 @@ void grpc_server_start(grpc_server *server) {
                          (size_t)server->max_requested_calls_per_cq, server);
   }
 
-  for (l = server->listeners; l; l = l->next) {
-    l->start(&exec_ctx, server, l->arg, server->pollsets,
-             server->pollset_count);
-  }
+  server_ref(server);
+  server->starting = true;
+  grpc_closure_sched(&exec_ctx, grpc_closure_create(start_listeners, server,
+                                                    grpc_executor_scheduler),
+                     GRPC_ERROR_NONE);
 
   grpc_exec_ctx_finish(&exec_ctx);
 }
@@ -1258,8 +1281,14 @@ void grpc_server_shutdown_and_notify(grpc_server *server,
   GRPC_API_TRACE("grpc_server_shutdown_and_notify(server=%p, cq=%p, tag=%p)", 3,
                  (server, cq, tag));
 
-  /* lock, and gather up some stuff to do */
+  /* wait for startup to be finished: locks mu_global */
   gpr_mu_lock(&server->mu_global);
+  while (server->starting) {
+    gpr_cv_wait(&server->starting_cv, &server->mu_global,
+                gpr_inf_future(GPR_CLOCK_REALTIME));
+  }
+
+  /* stay locked, and gather up some stuff to do */
   grpc_cq_begin_op(cq, tag);
   if (server->shutdown_published) {
     grpc_cq_end_op(&exec_ctx, cq, tag, GRPC_ERROR_NONE, done_published_shutdown,

src/core/lib/transport/byte_stream.c

@@ -40,10 +40,15 @@
 #include "src/core/lib/slice/slice_internal.h"
 
 int grpc_byte_stream_next(grpc_exec_ctx *exec_ctx,
-                          grpc_byte_stream *byte_stream, grpc_slice *slice,
-                          size_t max_size_hint, grpc_closure *on_complete) {
-  return byte_stream->next(exec_ctx, byte_stream, slice, max_size_hint,
-                           on_complete);
+                          grpc_byte_stream *byte_stream, size_t max_size_hint,
+                          grpc_closure *on_complete) {
+  return byte_stream->next(exec_ctx, byte_stream, max_size_hint, on_complete);
+}
+
+grpc_error *grpc_byte_stream_pull(grpc_exec_ctx *exec_ctx,
+                                  grpc_byte_stream *byte_stream,
+                                  grpc_slice *slice) {
+  return byte_stream->pull(exec_ctx, byte_stream, slice);
 }
 
 void grpc_byte_stream_destroy(grpc_exec_ctx *exec_ctx,
@@ -53,16 +58,24 @@ void grpc_byte_stream_destroy(grpc_exec_ctx *exec_ctx,
 
 /* slice_buffer_stream */
 
-static int slice_buffer_stream_next(grpc_exec_ctx *exec_ctx,
+static bool slice_buffer_stream_next(grpc_exec_ctx *exec_ctx,
                                      grpc_byte_stream *byte_stream,
-                                    grpc_slice *slice, size_t max_size_hint,
+                                     size_t max_size_hint,
                                      grpc_closure *on_complete) {
   grpc_slice_buffer_stream *stream = (grpc_slice_buffer_stream *)byte_stream;
   GPR_ASSERT(stream->cursor < stream->backing_buffer->count);
+  return true;
+}
+
+static grpc_error *slice_buffer_stream_pull(grpc_exec_ctx *exec_ctx,
+                                            grpc_byte_stream *byte_stream,
+                                            grpc_slice *slice) {
+  grpc_slice_buffer_stream *stream = (grpc_slice_buffer_stream *)byte_stream;
+  GPR_ASSERT(stream->cursor < stream->backing_buffer->count);
   *slice =
       grpc_slice_ref_internal(stream->backing_buffer->slices[stream->cursor]);
   stream->cursor++;
-  return 1;
+  return GRPC_ERROR_NONE;
 }
 
 static void slice_buffer_stream_destroy(grpc_exec_ctx *exec_ctx,
@@ -75,6 +88,7 @@ void grpc_slice_buffer_stream_init(grpc_slice_buffer_stream *stream,
   stream->base.length = (uint32_t)slice_buffer->length;
   stream->base.flags = flags;
   stream->base.next = slice_buffer_stream_next;
+  stream->base.pull = slice_buffer_stream_pull;
   stream->base.destroy = slice_buffer_stream_destroy;
   stream->backing_buffer = slice_buffer;
   stream->cursor = 0;

src/core/lib/transport/byte_stream.h

@@ -49,9 +49,10 @@ typedef struct grpc_byte_stream grpc_byte_stream;
 struct grpc_byte_stream {
   uint32_t length;
   uint32_t flags;
-  int (*next)(grpc_exec_ctx *exec_ctx, grpc_byte_stream *byte_stream,
-              grpc_slice *slice, size_t max_size_hint,
-              grpc_closure *on_complete);
+  bool (*next)(grpc_exec_ctx *exec_ctx, grpc_byte_stream *byte_stream,
+               size_t max_size_hint, grpc_closure *on_complete);
+  grpc_error *(*pull)(grpc_exec_ctx *exec_ctx, grpc_byte_stream *byte_stream,
+                      grpc_slice *slice);
   void (*destroy)(grpc_exec_ctx *exec_ctx, grpc_byte_stream *byte_stream);
 };
 
@@ -61,12 +62,20 @@ struct grpc_byte_stream {
  *
  * max_size_hint can be set as a hint as to the maximum number
  * of bytes that would be acceptable to read.
+ */
+int grpc_byte_stream_next(grpc_exec_ctx *exec_ctx,
+                          grpc_byte_stream *byte_stream, size_t max_size_hint,
+                          grpc_closure *on_complete);
+
+/* returns the next slice in the byte stream when it is ready (indicated by
+ * either grpc_byte_stream_next returning 1 or on_complete passed to
+ * grpc_byte_stream_next is called).
  *
  * once a slice is returned into *slice, it is owned by the caller.
  */
-int grpc_byte_stream_next(grpc_exec_ctx *exec_ctx,
-                          grpc_byte_stream *byte_stream, grpc_slice *slice,
-                          size_t max_size_hint, grpc_closure *on_complete);
+grpc_error *grpc_byte_stream_pull(grpc_exec_ctx *exec_ctx,
+                                  grpc_byte_stream *byte_stream,
+                                  grpc_slice *slice);
 
 void grpc_byte_stream_destroy(grpc_exec_ctx *exec_ctx,
                               grpc_byte_stream *byte_stream);

src/core/lib/transport/static_metadata.c

@@ -97,23 +97,23 @@ static uint8_t g_bytes[] = {
     101, 105, 102, 45,  110, 111, 110, 101, 45,  109, 97,  116, 99,  104, 105,
     102, 45,  114, 97,  110, 103, 101, 105, 102, 45,  117, 110, 109, 111, 100,
     105, 102, 105, 101, 100, 45,  115, 105, 110, 99,  101, 108, 97,  115, 116,
-    45,  109, 111, 100, 105, 102, 105, 101, 100, 108, 105, 110, 107, 108, 111,
-    99,  97,  116, 105, 111, 110, 109, 97,  120, 45,  102, 111, 114, 119, 97,
-    114, 100, 115, 112, 114, 111, 120, 121, 45,  97,  117, 116, 104, 101, 110,
-    116, 105, 99,  97,  116, 101, 112, 114, 111, 120, 121, 45,  97,  117, 116,
-    104, 111, 114, 105, 122, 97,  116, 105, 111, 110, 114, 97,  110, 103, 101,
-    114, 101, 102, 101, 114, 101, 114, 114, 101, 102, 114, 101, 115, 104, 114,
-    101, 116, 114, 121, 45,  97,  102, 116, 101, 114, 115, 101, 114, 118, 101,
-    114, 115, 101, 116, 45,  99,  111, 111, 107, 105, 101, 115, 116, 114, 105,
-    99,  116, 45,  116, 114, 97,  110, 115, 112, 111, 114, 116, 45,  115, 101,
-    99,  117, 114, 105, 116, 121, 116, 114, 97,  110, 115, 102, 101, 114, 45,
-    101, 110, 99,  111, 100, 105, 110, 103, 118, 97,  114, 121, 118, 105, 97,
-    119, 119, 119, 45,  97,  117, 116, 104, 101, 110, 116, 105, 99,  97,  116,
-    101, 105, 100, 101, 110, 116, 105, 116, 121, 44,  100, 101, 102, 108, 97,
-    116, 101, 105, 100, 101, 110, 116, 105, 116, 121, 44,  103, 122, 105, 112,
-    100, 101, 102, 108, 97,  116, 101, 44,  103, 122, 105, 112, 105, 100, 101,
-    110, 116, 105, 116, 121, 44,  100, 101, 102, 108, 97,  116, 101, 44,  103,
-    122, 105, 112};
+    45,  109, 111, 100, 105, 102, 105, 101, 100, 108, 98,  45,  99,  111, 115,
+    116, 45,  98,  105, 110, 108, 105, 110, 107, 108, 111, 99,  97,  116, 105,
+    111, 110, 109, 97,  120, 45,  102, 111, 114, 119, 97,  114, 100, 115, 112,
+    114, 111, 120, 121, 45,  97,  117, 116, 104, 101, 110, 116, 105, 99,  97,
+    116, 101, 112, 114, 111, 120, 121, 45,  97,  117, 116, 104, 111, 114, 105,
+    122, 97,  116, 105, 111, 110, 114, 97,  110, 103, 101, 114, 101, 102, 101,
+    114, 101, 114, 114, 101, 102, 114, 101, 115, 104, 114, 101, 116, 114, 121,
+    45,  97,  102, 116, 101, 114, 115, 101, 114, 118, 101, 114, 115, 101, 116,
+    45,  99,  111, 111, 107, 105, 101, 115, 116, 114, 105, 99,  116, 45,  116,
+    114, 97,  110, 115, 112, 111, 114, 116, 45,  115, 101, 99,  117, 114, 105,
+    116, 121, 116, 114, 97,  110, 115, 102, 101, 114, 45,  101, 110, 99,  111,
+    100, 105, 110, 103, 118, 97,  114, 121, 118, 105, 97,  119, 119, 119, 45,
+    97,  117, 116, 104, 101, 110, 116, 105, 99,  97,  116, 101, 105, 100, 101,
+    110, 116, 105, 116, 121, 44,  100, 101, 102, 108, 97,  116, 101, 105, 100,
+    101, 110, 116, 105, 116, 121, 44,  103, 122, 105, 112, 100, 101, 102, 108,
+    97,  116, 101, 44,  103, 122, 105, 112, 105, 100, 101, 110, 116, 105, 116,
+    121, 44,  100, 101, 102, 108, 97,  116, 101, 44,  103, 122, 105, 112};
 
 static void static_ref(void *unused) {}
 static void static_unref(grpc_exec_ctx *exec_ctx, void *unused) {}
@@ -223,6 +223,7 @@ grpc_slice_refcount grpc_static_metadata_refcounts[GRPC_STATIC_MDSTR_COUNT] = {
     {&grpc_static_metadata_vtable, &static_sub_refcnt},
     {&grpc_static_metadata_vtable, &static_sub_refcnt},
     {&grpc_static_metadata_vtable, &static_sub_refcnt},
+    {&grpc_static_metadata_vtable, &static_sub_refcnt},
 };
 
 const grpc_slice grpc_static_slice_table[GRPC_STATIC_MDSTR_COUNT] = {
@@ -383,64 +384,67 @@ const grpc_slice grpc_static_slice_table[GRPC_STATIC_MDSTR_COUNT] = {
     {.refcount = &grpc_static_metadata_refcounts[77],
      .data.refcounted = {g_bytes + 791, 13}},
     {.refcount = &grpc_static_metadata_refcounts[78],
-     .data.refcounted = {g_bytes + 804, 4}},
+     .data.refcounted = {g_bytes + 804, 11}},
     {.refcount = &grpc_static_metadata_refcounts[79],
-     .data.refcounted = {g_bytes + 808, 8}},
+     .data.refcounted = {g_bytes + 815, 4}},
     {.refcount = &grpc_static_metadata_refcounts[80],
-     .data.refcounted = {g_bytes + 816, 12}},
+     .data.refcounted = {g_bytes + 819, 8}},
     {.refcount = &grpc_static_metadata_refcounts[81],
-     .data.refcounted = {g_bytes + 828, 18}},
+     .data.refcounted = {g_bytes + 827, 12}},
     {.refcount = &grpc_static_metadata_refcounts[82],
-     .data.refcounted = {g_bytes + 846, 19}},
+     .data.refcounted = {g_bytes + 839, 18}},
     {.refcount = &grpc_static_metadata_refcounts[83],
-     .data.refcounted = {g_bytes + 865, 5}},
+     .data.refcounted = {g_bytes + 857, 19}},
     {.refcount = &grpc_static_metadata_refcounts[84],
-     .data.refcounted = {g_bytes + 870, 7}},
+     .data.refcounted = {g_bytes + 876, 5}},
     {.refcount = &grpc_static_metadata_refcounts[85],
-     .data.refcounted = {g_bytes + 877, 7}},
+     .data.refcounted = {g_bytes + 881, 7}},
     {.refcount = &grpc_static_metadata_refcounts[86],
-     .data.refcounted = {g_bytes + 884, 11}},
+     .data.refcounted = {g_bytes + 888, 7}},
     {.refcount = &grpc_static_metadata_refcounts[87],
-     .data.refcounted = {g_bytes + 895, 6}},
+     .data.refcounted = {g_bytes + 895, 11}},
     {.refcount = &grpc_static_metadata_refcounts[88],
-     .data.refcounted = {g_bytes + 901, 10}},
+     .data.refcounted = {g_bytes + 906, 6}},
     {.refcount = &grpc_static_metadata_refcounts[89],
-     .data.refcounted = {g_bytes + 911, 25}},
+     .data.refcounted = {g_bytes + 912, 10}},
     {.refcount = &grpc_static_metadata_refcounts[90],
-     .data.refcounted = {g_bytes + 936, 17}},
+     .data.refcounted = {g_bytes + 922, 25}},
     {.refcount = &grpc_static_metadata_refcounts[91],
-     .data.refcounted = {g_bytes + 953, 4}},
+     .data.refcounted = {g_bytes + 947, 17}},
     {.refcount = &grpc_static_metadata_refcounts[92],
-     .data.refcounted = {g_bytes + 957, 3}},
+     .data.refcounted = {g_bytes + 964, 4}},
     {.refcount = &grpc_static_metadata_refcounts[93],
-     .data.refcounted = {g_bytes + 960, 16}},
+     .data.refcounted = {g_bytes + 968, 3}},
     {.refcount = &grpc_static_metadata_refcounts[94],
-     .data.refcounted = {g_bytes + 976, 16}},
+     .data.refcounted = {g_bytes + 971, 16}},
     {.refcount = &grpc_static_metadata_refcounts[95],
-     .data.refcounted = {g_bytes + 992, 13}},
+     .data.refcounted = {g_bytes + 987, 16}},
     {.refcount = &grpc_static_metadata_refcounts[96],
-     .data.refcounted = {g_bytes + 1005, 12}},
+     .data.refcounted = {g_bytes + 1003, 13}},
     {.refcount = &grpc_static_metadata_refcounts[97],
-     .data.refcounted = {g_bytes + 1017, 21}},
+     .data.refcounted = {g_bytes + 1016, 12}},
+    {.refcount = &grpc_static_metadata_refcounts[98],
+     .data.refcounted = {g_bytes + 1028, 21}},
 };
 
 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, 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, 2, 4, 4, 6, 6, 8, 8};
+    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, 0, 0, 0, 0, 0, 0, 0, 0, 2, 4, 4, 6, 6, 8, 8};
 
 static const int8_t elems_r[] = {
-    10, 8,   -3,  0,  9,   21,  -76, 22,  0,   10,  -7,  0,  0,  0,  14, 0,
-    13, 12,  11,  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,  -50, -51, 15, -53, -54, -55, -56, -56, -57, -58, 0,  37, 36, 35, 34,
-    33, 32,  31,  30, 29,  28,  27,  26,  25,  24,  23,  22, 21, 20, 19, 18,
-    17, 16,  15,  14, 13,  12,  11,  10,  13,  12,  11,  10, 9,  8,  7,  0};
+    10,  8,   -3,  0,   9,  21, -77, 22,  0,   10, -7,  0,   0,   0,
+    14,  0,   13,  12,  11, 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,   -50, -51, 16, -53, -54, -55, -56,
+    -56, -57, -58, -59, 0,  37, 36,  35,  34,  33, 32,  31,  30,  29,
+    28,  27,  26,  25,  24, 23, 22,  21,  20,  19, 18,  17,  16,  15,
+    14,  13,  12,  11,  10, 13, 12,  11,  10,  9,  8,   7,   0};
 static uint32_t elems_phash(uint32_t i) {
   i -= 42;
-  uint32_t x = i % 96;
-  uint32_t y = i / 96;
+  uint32_t x = i % 97;
+  uint32_t y = i / 97;
   uint32_t h = x;
   if (y < GPR_ARRAY_SIZE(elems_r)) {
     uint32_t delta = (uint32_t)elems_r[y];
@@ -450,29 +454,30 @@ static uint32_t elems_phash(uint32_t i) {
 }
 
 static const uint16_t elem_keys[] = {
-    1009, 1010, 1011, 240,  241,  242,  243,  244,  138,  139,  42,   43,
-    429,  430,  431,  911,  912,  913,  712,  713,  1392, 522,  714,  1588,
-    1686, 1784, 4822, 4920, 4951, 5116, 5214, 5312, 5410, 1405, 5508, 5606,
-    5704, 5802, 5900, 5998, 6096, 6194, 6292, 6390, 6488, 6586, 6684, 6782,
-    6880, 6978, 7076, 7174, 7272, 7370, 7468, 7566, 7664, 7762, 7860, 7958,
-    8056, 8154, 8252, 8350, 8448, 1074, 1075, 1076, 1077, 8546, 8644, 8742,
-    8840, 8938, 9036, 9134, 0,    314,  0,    0,    0,    0,    0,    0,
+    1019, 1020, 1021, 242,  243,  244,  245,  246,  139,  140,  42,   43,
+    433,  434,  435,  920,  921,  922,  719,  720,  1406, 527,  721,  1604,
+    1703, 1802, 4871, 4970, 5001, 5168, 5267, 5366, 5465, 1419, 5564, 5663,
+    5762, 5861, 5960, 6059, 6158, 6257, 6356, 6455, 6554, 6653, 6752, 6851,
+    6950, 7049, 7148, 7247, 7346, 7445, 7544, 7643, 7742, 7841, 7940, 8039,
+    8138, 8237, 8336, 8435, 8534, 8633, 1085, 1086, 1087, 1088, 8732, 8831,
+    8930, 9029, 9128, 9227, 9326, 0,    317,  0,    0,    0,    0,    0,
+    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,
+    0,    0,    0,    0,    0,    133,  233,  234,  0,    0,    0,    0,
     0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,
-    0,    0,    0,    0,    132,  231,  232,  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};
 static const uint8_t elem_idxs[] = {
-    73,  76,  74,  19,  20,  21,  22,  23,  15,  16,  17,  18,  11,  12,  13,
-    3,   4,   5,   0,   1,   41,  6,   2,   69,  48,  55,  24,  25,  26,  27,
+    74,  77,  75,  19,  20,  21,  22,  23,  15,  16,  17,  18,  11,  12,  13,
+    3,   4,   5,   0,   1,   41,  6,   2,   70,  48,  55,  24,  25,  26,  27,
     28,  29,  30,  7,   31,  32,  33,  34,  35,  36,  37,  38,  39,  40,  42,
     43,  44,  45,  46,  47,  49,  50,  51,  52,  53,  54,  56,  57,  58,  59,
-    60,  61,  62,  63,  64,  75,  77,  78,  79,  65,  66,  67,  68,  70,  71,
-    72,  255, 14,  255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
-    255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 8,   9,   10};
+    60,  61,  62,  63,  64,  65,  76,  78,  79,  80,  66,  67,  68,  69,  71,
+    72,  73,  255, 14,  255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
+    255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 8,   9,   10};
 
 grpc_mdelem grpc_static_mdelem_for_static_strings(int a, int b) {
   if (a == -1 || b == -1) return GRPC_MDNULL;
-  uint32_t k = (uint32_t)(a * 98 + b);
+  uint32_t k = (uint32_t)(a * 99 + b);
   uint32_t h = elems_phash(k);
   return h < GPR_ARRAY_SIZE(elem_keys) && elem_keys[h] == k
              ? GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[elem_idxs[h]],
@@ -706,71 +711,75 @@ grpc_mdelem_data grpc_static_mdelem_table[GRPC_STATIC_MDELEM_COUNT] = {
      {.refcount = &grpc_static_metadata_refcounts[20],
       .data.refcounted = {g_bytes + 234, 0}}},
     {{.refcount = &grpc_static_metadata_refcounts[78],
-      .data.refcounted = {g_bytes + 804, 4}},
+      .data.refcounted = {g_bytes + 804, 11}},
      {.refcount = &grpc_static_metadata_refcounts[20],
       .data.refcounted = {g_bytes + 234, 0}}},
     {{.refcount = &grpc_static_metadata_refcounts[79],
-      .data.refcounted = {g_bytes + 808, 8}},
+      .data.refcounted = {g_bytes + 815, 4}},
      {.refcount = &grpc_static_metadata_refcounts[20],
       .data.refcounted = {g_bytes + 234, 0}}},
     {{.refcount = &grpc_static_metadata_refcounts[80],
-      .data.refcounted = {g_bytes + 816, 12}},
+      .data.refcounted = {g_bytes + 819, 8}},
      {.refcount = &grpc_static_metadata_refcounts[20],
       .data.refcounted = {g_bytes + 234, 0}}},
     {{.refcount = &grpc_static_metadata_refcounts[81],
-      .data.refcounted = {g_bytes + 828, 18}},
+      .data.refcounted = {g_bytes + 827, 12}},
      {.refcount = &grpc_static_metadata_refcounts[20],
       .data.refcounted = {g_bytes + 234, 0}}},
     {{.refcount = &grpc_static_metadata_refcounts[82],
-      .data.refcounted = {g_bytes + 846, 19}},
+      .data.refcounted = {g_bytes + 839, 18}},
      {.refcount = &grpc_static_metadata_refcounts[20],
       .data.refcounted = {g_bytes + 234, 0}}},
     {{.refcount = &grpc_static_metadata_refcounts[83],
-      .data.refcounted = {g_bytes + 865, 5}},
+      .data.refcounted = {g_bytes + 857, 19}},
      {.refcount = &grpc_static_metadata_refcounts[20],
       .data.refcounted = {g_bytes + 234, 0}}},
     {{.refcount = &grpc_static_metadata_refcounts[84],
-      .data.refcounted = {g_bytes + 870, 7}},
+      .data.refcounted = {g_bytes + 876, 5}},
      {.refcount = &grpc_static_metadata_refcounts[20],
       .data.refcounted = {g_bytes + 234, 0}}},
     {{.refcount = &grpc_static_metadata_refcounts[85],
-      .data.refcounted = {g_bytes + 877, 7}},
+      .data.refcounted = {g_bytes + 881, 7}},
      {.refcount = &grpc_static_metadata_refcounts[20],
       .data.refcounted = {g_bytes + 234, 0}}},
     {{.refcount = &grpc_static_metadata_refcounts[86],
-      .data.refcounted = {g_bytes + 884, 11}},
+      .data.refcounted = {g_bytes + 888, 7}},
      {.refcount = &grpc_static_metadata_refcounts[20],
       .data.refcounted = {g_bytes + 234, 0}}},
     {{.refcount = &grpc_static_metadata_refcounts[87],
-      .data.refcounted = {g_bytes + 895, 6}},
+      .data.refcounted = {g_bytes + 895, 11}},
      {.refcount = &grpc_static_metadata_refcounts[20],
       .data.refcounted = {g_bytes + 234, 0}}},
     {{.refcount = &grpc_static_metadata_refcounts[88],
-      .data.refcounted = {g_bytes + 901, 10}},
+      .data.refcounted = {g_bytes + 906, 6}},
      {.refcount = &grpc_static_metadata_refcounts[20],
       .data.refcounted = {g_bytes + 234, 0}}},
     {{.refcount = &grpc_static_metadata_refcounts[89],
-      .data.refcounted = {g_bytes + 911, 25}},
+      .data.refcounted = {g_bytes + 912, 10}},
      {.refcount = &grpc_static_metadata_refcounts[20],
       .data.refcounted = {g_bytes + 234, 0}}},
     {{.refcount = &grpc_static_metadata_refcounts[90],
-      .data.refcounted = {g_bytes + 936, 17}},
+      .data.refcounted = {g_bytes + 922, 25}},
      {.refcount = &grpc_static_metadata_refcounts[20],
       .data.refcounted = {g_bytes + 234, 0}}},
-    {{.refcount = &grpc_static_metadata_refcounts[16],
-      .data.refcounted = {g_bytes + 200, 10}},
+    {{.refcount = &grpc_static_metadata_refcounts[91],
+      .data.refcounted = {g_bytes + 947, 17}},
      {.refcount = &grpc_static_metadata_refcounts[20],
       .data.refcounted = {g_bytes + 234, 0}}},
-    {{.refcount = &grpc_static_metadata_refcounts[91],
-      .data.refcounted = {g_bytes + 953, 4}},
+    {{.refcount = &grpc_static_metadata_refcounts[16],
+      .data.refcounted = {g_bytes + 200, 10}},
      {.refcount = &grpc_static_metadata_refcounts[20],
       .data.refcounted = {g_bytes + 234, 0}}},
     {{.refcount = &grpc_static_metadata_refcounts[92],
-      .data.refcounted = {g_bytes + 957, 3}},
+      .data.refcounted = {g_bytes + 964, 4}},
      {.refcount = &grpc_static_metadata_refcounts[20],
       .data.refcounted = {g_bytes + 234, 0}}},
     {{.refcount = &grpc_static_metadata_refcounts[93],
-      .data.refcounted = {g_bytes + 960, 16}},
+      .data.refcounted = {g_bytes + 968, 3}},
+     {.refcount = &grpc_static_metadata_refcounts[20],
+      .data.refcounted = {g_bytes + 234, 0}}},
+    {{.refcount = &grpc_static_metadata_refcounts[94],
+      .data.refcounted = {g_bytes + 971, 16}},
      {.refcount = &grpc_static_metadata_refcounts[20],
       .data.refcounted = {g_bytes + 234, 0}}},
     {{.refcount = &grpc_static_metadata_refcounts[10],
@@ -783,24 +792,24 @@ grpc_mdelem_data grpc_static_mdelem_table[GRPC_STATIC_MDELEM_COUNT] = {
       .data.refcounted = {g_bytes + 377, 7}}},
     {{.refcount = &grpc_static_metadata_refcounts[10],
       .data.refcounted = {g_bytes + 90, 20}},
-     {.refcount = &grpc_static_metadata_refcounts[94],
-      .data.refcounted = {g_bytes + 976, 16}}},
+     {.refcount = &grpc_static_metadata_refcounts[95],
+      .data.refcounted = {g_bytes + 987, 16}}},
     {{.refcount = &grpc_static_metadata_refcounts[10],
       .data.refcounted = {g_bytes + 90, 20}},
      {.refcount = &grpc_static_metadata_refcounts[30],
       .data.refcounted = {g_bytes + 373, 4}}},
-    {{.refcount = &grpc_static_metadata_refcounts[10],
-      .data.refcounted = {g_bytes + 90, 20}},
-     {.refcount = &grpc_static_metadata_refcounts[95],
-      .data.refcounted = {g_bytes + 992, 13}}},
     {{.refcount = &grpc_static_metadata_refcounts[10],
       .data.refcounted = {g_bytes + 90, 20}},
      {.refcount = &grpc_static_metadata_refcounts[96],
-      .data.refcounted = {g_bytes + 1005, 12}}},
+      .data.refcounted = {g_bytes + 1003, 13}}},
     {{.refcount = &grpc_static_metadata_refcounts[10],
       .data.refcounted = {g_bytes + 90, 20}},
      {.refcount = &grpc_static_metadata_refcounts[97],
-      .data.refcounted = {g_bytes + 1017, 21}}},
+      .data.refcounted = {g_bytes + 1016, 12}}},
+    {{.refcount = &grpc_static_metadata_refcounts[10],
+      .data.refcounted = {g_bytes + 90, 20}},
+     {.refcount = &grpc_static_metadata_refcounts[98],
+      .data.refcounted = {g_bytes + 1028, 21}}},
 };
-const uint8_t grpc_static_accept_encoding_metadata[8] = {0,  73, 74, 75,
-                                                         76, 77, 78, 79};
+const uint8_t grpc_static_accept_encoding_metadata[8] = {0,  74, 75, 76,
+                                                         77, 78, 79, 80};

src/core/lib/transport/static_metadata.h

@@ -44,7 +44,7 @@
 
 #include "src/core/lib/transport/metadata.h"
 
-#define GRPC_STATIC_MDSTR_COUNT 98
+#define GRPC_STATIC_MDSTR_COUNT 99
 extern const grpc_slice grpc_static_slice_table[GRPC_STATIC_MDSTR_COUNT];
 /* ":path" */
 #define GRPC_MDSTR_PATH (grpc_static_slice_table[0])
@@ -205,47 +205,49 @@ extern const grpc_slice grpc_static_slice_table[GRPC_STATIC_MDSTR_COUNT];
 #define GRPC_MDSTR_IF_UNMODIFIED_SINCE (grpc_static_slice_table[76])
 /* "last-modified" */
 #define GRPC_MDSTR_LAST_MODIFIED (grpc_static_slice_table[77])
+/* "lb-cost-bin" */
+#define GRPC_MDSTR_LB_COST_BIN (grpc_static_slice_table[78])
 /* "link" */
-#define GRPC_MDSTR_LINK (grpc_static_slice_table[78])
+#define GRPC_MDSTR_LINK (grpc_static_slice_table[79])
 /* "location" */
-#define GRPC_MDSTR_LOCATION (grpc_static_slice_table[79])
+#define GRPC_MDSTR_LOCATION (grpc_static_slice_table[80])
 /* "max-forwards" */
-#define GRPC_MDSTR_MAX_FORWARDS (grpc_static_slice_table[80])
+#define GRPC_MDSTR_MAX_FORWARDS (grpc_static_slice_table[81])
 /* "proxy-authenticate" */
-#define GRPC_MDSTR_PROXY_AUTHENTICATE (grpc_static_slice_table[81])
+#define GRPC_MDSTR_PROXY_AUTHENTICATE (grpc_static_slice_table[82])
 /* "proxy-authorization" */
-#define GRPC_MDSTR_PROXY_AUTHORIZATION (grpc_static_slice_table[82])
+#define GRPC_MDSTR_PROXY_AUTHORIZATION (grpc_static_slice_table[83])
 /* "range" */
-#define GRPC_MDSTR_RANGE (grpc_static_slice_table[83])
+#define GRPC_MDSTR_RANGE (grpc_static_slice_table[84])
 /* "referer" */
-#define GRPC_MDSTR_REFERER (grpc_static_slice_table[84])
+#define GRPC_MDSTR_REFERER (grpc_static_slice_table[85])
 /* "refresh" */
-#define GRPC_MDSTR_REFRESH (grpc_static_slice_table[85])
+#define GRPC_MDSTR_REFRESH (grpc_static_slice_table[86])
 /* "retry-after" */
-#define GRPC_MDSTR_RETRY_AFTER (grpc_static_slice_table[86])
+#define GRPC_MDSTR_RETRY_AFTER (grpc_static_slice_table[87])
 /* "server" */
-#define GRPC_MDSTR_SERVER (grpc_static_slice_table[87])
+#define GRPC_MDSTR_SERVER (grpc_static_slice_table[88])
 /* "set-cookie" */
-#define GRPC_MDSTR_SET_COOKIE (grpc_static_slice_table[88])
+#define GRPC_MDSTR_SET_COOKIE (grpc_static_slice_table[89])
 /* "strict-transport-security" */
-#define GRPC_MDSTR_STRICT_TRANSPORT_SECURITY (grpc_static_slice_table[89])
+#define GRPC_MDSTR_STRICT_TRANSPORT_SECURITY (grpc_static_slice_table[90])
 /* "transfer-encoding" */
-#define GRPC_MDSTR_TRANSFER_ENCODING (grpc_static_slice_table[90])
+#define GRPC_MDSTR_TRANSFER_ENCODING (grpc_static_slice_table[91])
 /* "vary" */
-#define GRPC_MDSTR_VARY (grpc_static_slice_table[91])
+#define GRPC_MDSTR_VARY (grpc_static_slice_table[92])
 /* "via" */
-#define GRPC_MDSTR_VIA (grpc_static_slice_table[92])
+#define GRPC_MDSTR_VIA (grpc_static_slice_table[93])
 /* "www-authenticate" */
-#define GRPC_MDSTR_WWW_AUTHENTICATE (grpc_static_slice_table[93])
+#define GRPC_MDSTR_WWW_AUTHENTICATE (grpc_static_slice_table[94])
 /* "identity,deflate" */
-#define GRPC_MDSTR_IDENTITY_COMMA_DEFLATE (grpc_static_slice_table[94])
+#define GRPC_MDSTR_IDENTITY_COMMA_DEFLATE (grpc_static_slice_table[95])
 /* "identity,gzip" */
-#define GRPC_MDSTR_IDENTITY_COMMA_GZIP (grpc_static_slice_table[95])
+#define GRPC_MDSTR_IDENTITY_COMMA_GZIP (grpc_static_slice_table[96])
 /* "deflate,gzip" */
-#define GRPC_MDSTR_DEFLATE_COMMA_GZIP (grpc_static_slice_table[96])
+#define GRPC_MDSTR_DEFLATE_COMMA_GZIP (grpc_static_slice_table[97])
 /* "identity,deflate,gzip" */
 #define GRPC_MDSTR_IDENTITY_COMMA_DEFLATE_COMMA_GZIP \
-  (grpc_static_slice_table[97])
+  (grpc_static_slice_table[98])
 
 extern const grpc_slice_refcount_vtable grpc_static_metadata_vtable;
 extern grpc_slice_refcount
@@ -257,7 +259,7 @@ extern grpc_slice_refcount
 #define GRPC_STATIC_METADATA_INDEX(static_slice) \
   ((int)((static_slice).refcount - grpc_static_metadata_refcounts))
 
-#define GRPC_STATIC_MDELEM_COUNT 80
+#define GRPC_STATIC_MDELEM_COUNT 81
 extern grpc_mdelem_data grpc_static_mdelem_table[GRPC_STATIC_MDELEM_COUNT];
 extern uintptr_t grpc_static_mdelem_user_data[GRPC_STATIC_MDELEM_COUNT];
 /* "grpc-status": "0" */
@@ -428,78 +430,81 @@ extern uintptr_t grpc_static_mdelem_user_data[GRPC_STATIC_MDELEM_COUNT];
 /* "lb-token": "" */
 #define GRPC_MDELEM_LB_TOKEN_EMPTY \
   (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[55], GRPC_MDELEM_STORAGE_STATIC))
+/* "lb-cost-bin": "" */
+#define GRPC_MDELEM_LB_COST_BIN_EMPTY \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[56], GRPC_MDELEM_STORAGE_STATIC))
 /* "link": "" */
 #define GRPC_MDELEM_LINK_EMPTY \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[56], GRPC_MDELEM_STORAGE_STATIC))
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[57], GRPC_MDELEM_STORAGE_STATIC))
 /* "location": "" */
 #define GRPC_MDELEM_LOCATION_EMPTY \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[57], GRPC_MDELEM_STORAGE_STATIC))
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[58], GRPC_MDELEM_STORAGE_STATIC))
 /* "max-forwards": "" */
 #define GRPC_MDELEM_MAX_FORWARDS_EMPTY \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[58], GRPC_MDELEM_STORAGE_STATIC))
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[59], GRPC_MDELEM_STORAGE_STATIC))
 /* "proxy-authenticate": "" */
 #define GRPC_MDELEM_PROXY_AUTHENTICATE_EMPTY \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[59], GRPC_MDELEM_STORAGE_STATIC))
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[60], GRPC_MDELEM_STORAGE_STATIC))
 /* "proxy-authorization": "" */
 #define GRPC_MDELEM_PROXY_AUTHORIZATION_EMPTY \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[60], GRPC_MDELEM_STORAGE_STATIC))
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[61], GRPC_MDELEM_STORAGE_STATIC))
 /* "range": "" */
 #define GRPC_MDELEM_RANGE_EMPTY \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[61], GRPC_MDELEM_STORAGE_STATIC))
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[62], GRPC_MDELEM_STORAGE_STATIC))
 /* "referer": "" */
 #define GRPC_MDELEM_REFERER_EMPTY \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[62], GRPC_MDELEM_STORAGE_STATIC))
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[63], GRPC_MDELEM_STORAGE_STATIC))
 /* "refresh": "" */
 #define GRPC_MDELEM_REFRESH_EMPTY \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[63], GRPC_MDELEM_STORAGE_STATIC))
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[64], GRPC_MDELEM_STORAGE_STATIC))
 /* "retry-after": "" */
 #define GRPC_MDELEM_RETRY_AFTER_EMPTY \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[64], GRPC_MDELEM_STORAGE_STATIC))
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[65], GRPC_MDELEM_STORAGE_STATIC))
 /* "server": "" */
 #define GRPC_MDELEM_SERVER_EMPTY \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[65], GRPC_MDELEM_STORAGE_STATIC))
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[66], GRPC_MDELEM_STORAGE_STATIC))
 /* "set-cookie": "" */
 #define GRPC_MDELEM_SET_COOKIE_EMPTY \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[66], GRPC_MDELEM_STORAGE_STATIC))
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[67], GRPC_MDELEM_STORAGE_STATIC))
 /* "strict-transport-security": "" */
 #define GRPC_MDELEM_STRICT_TRANSPORT_SECURITY_EMPTY \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[67], GRPC_MDELEM_STORAGE_STATIC))
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[68], GRPC_MDELEM_STORAGE_STATIC))
 /* "transfer-encoding": "" */
 #define GRPC_MDELEM_TRANSFER_ENCODING_EMPTY \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[68], GRPC_MDELEM_STORAGE_STATIC))
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[69], GRPC_MDELEM_STORAGE_STATIC))
 /* "user-agent": "" */
 #define GRPC_MDELEM_USER_AGENT_EMPTY \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[69], GRPC_MDELEM_STORAGE_STATIC))
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[70], GRPC_MDELEM_STORAGE_STATIC))
 /* "vary": "" */
 #define GRPC_MDELEM_VARY_EMPTY \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[70], GRPC_MDELEM_STORAGE_STATIC))
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[71], GRPC_MDELEM_STORAGE_STATIC))
 /* "via": "" */
 #define GRPC_MDELEM_VIA_EMPTY \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[71], GRPC_MDELEM_STORAGE_STATIC))
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[72], GRPC_MDELEM_STORAGE_STATIC))
 /* "www-authenticate": "" */
 #define GRPC_MDELEM_WWW_AUTHENTICATE_EMPTY \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[72], GRPC_MDELEM_STORAGE_STATIC))
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[73], GRPC_MDELEM_STORAGE_STATIC))
 /* "grpc-accept-encoding": "identity" */
 #define GRPC_MDELEM_GRPC_ACCEPT_ENCODING_IDENTITY \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[73], GRPC_MDELEM_STORAGE_STATIC))
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[74], GRPC_MDELEM_STORAGE_STATIC))
 /* "grpc-accept-encoding": "deflate" */
 #define GRPC_MDELEM_GRPC_ACCEPT_ENCODING_DEFLATE \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[74], GRPC_MDELEM_STORAGE_STATIC))
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[75], GRPC_MDELEM_STORAGE_STATIC))
 /* "grpc-accept-encoding": "identity,deflate" */
 #define GRPC_MDELEM_GRPC_ACCEPT_ENCODING_IDENTITY_COMMA_DEFLATE \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[75], GRPC_MDELEM_STORAGE_STATIC))
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[76], GRPC_MDELEM_STORAGE_STATIC))
 /* "grpc-accept-encoding": "gzip" */
 #define GRPC_MDELEM_GRPC_ACCEPT_ENCODING_GZIP \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[76], GRPC_MDELEM_STORAGE_STATIC))
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[77], GRPC_MDELEM_STORAGE_STATIC))
 /* "grpc-accept-encoding": "identity,gzip" */
 #define GRPC_MDELEM_GRPC_ACCEPT_ENCODING_IDENTITY_COMMA_GZIP \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[77], GRPC_MDELEM_STORAGE_STATIC))
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[78], GRPC_MDELEM_STORAGE_STATIC))
 /* "grpc-accept-encoding": "deflate,gzip" */
 #define GRPC_MDELEM_GRPC_ACCEPT_ENCODING_DEFLATE_COMMA_GZIP \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[78], GRPC_MDELEM_STORAGE_STATIC))
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[79], GRPC_MDELEM_STORAGE_STATIC))
 /* "grpc-accept-encoding": "identity,deflate,gzip" */
 #define GRPC_MDELEM_GRPC_ACCEPT_ENCODING_IDENTITY_COMMA_DEFLATE_COMMA_GZIP \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[79], GRPC_MDELEM_STORAGE_STATIC))
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[80], GRPC_MDELEM_STORAGE_STATIC))
 
 grpc_mdelem grpc_static_mdelem_for_static_strings(int a, int b);
 typedef enum {

src/cpp/server/server_builder.cc

@@ -337,10 +337,7 @@ std::unique_ptr<Server> ServerBuilder::BuildAndStart() {
   }
 
   auto cqs_data = cqs_.empty() ? nullptr : &cqs_[0];
-  if (!server->Start(cqs_data, cqs_.size())) {
-    if (added_port) server->Shutdown();
-    return nullptr;
-  }
+  server->Start(cqs_data, cqs_.size());
 
   for (auto plugin = plugins_.begin(); plugin != plugins_.end(); plugin++) {
     (*plugin)->Finish(initializer);

src/cpp/server/server_cc.cc

@@ -503,11 +503,11 @@ int Server::AddListeningPort(const grpc::string& addr,
                              ServerCredentials* creds) {
   GPR_ASSERT(!started_);
   int port = creds->AddPortToServer(addr, server_);
-  global_callbacks_->AddPort(this, port);
+  global_callbacks_->AddPort(this, addr, creds, port);
   return port;
 }
 
-bool Server::Start(ServerCompletionQueue** cqs, size_t num_cqs) {
+void Server::Start(ServerCompletionQueue** cqs, size_t num_cqs) {
   GPR_ASSERT(!started_);
   global_callbacks_->PreServerStart(this);
   started_ = true;
@@ -543,8 +543,6 @@ bool Server::Start(ServerCompletionQueue** cqs, size_t num_cqs) {
   for (auto it = sync_req_mgrs_.begin(); it != sync_req_mgrs_.end(); it++) {
     (*it)->Start();
   }
-
-  return true;
 }
 
 void Server::ShutdownInternal(gpr_timespec deadline) {

src/cpp/server/server_context.cc

@@ -229,17 +229,9 @@ const struct census_context* ServerContext::census_context() const {
 void ServerContext::SetLoadReportingCosts(
     const std::vector<grpc::string>& cost_data) {
   if (call_ == nullptr) return;
-  grpc_load_reporting_cost_context* cost_ctx =
-      static_cast<grpc_load_reporting_cost_context*>(
-          gpr_malloc(sizeof(*cost_ctx)));
-  cost_ctx->values_count = cost_data.size();
-  cost_ctx->values = static_cast<grpc_slice*>(
-      gpr_malloc(sizeof(*cost_ctx->values) * cost_ctx->values_count));
-  for (size_t i = 0; i < cost_ctx->values_count; ++i) {
-    cost_ctx->values[i] =
-        grpc_slice_from_copied_buffer(cost_data[i].data(), cost_data[i].size());
+  for (const auto& cost_datum : cost_data) {
+    AddTrailingMetadata(GRPC_LB_COST_MD_KEY, cost_datum);
   }
-  grpc_call_set_load_reporting_cost_context(call_, cost_ctx);
 }
 
 }  // namespace grpc

src/csharp/Grpc.Core.Tests/AppDomainUnloadTest.cs

@@ -72,10 +72,6 @@ namespace Grpc.Core.Tests
             public AppDomainTestClass()
             {
                 var helper = new MockServiceHelper(Host);
-                var server = helper.GetServer();
-                server.Start();
-                var channel = helper.GetChannel();
-
                 var readyToShutdown = new TaskCompletionSource<object>();
                 helper.DuplexStreamingHandler = new DuplexStreamingServerMethod<string, string>(async (requestStream, responseStream, context) =>
                 {
@@ -83,6 +79,10 @@ namespace Grpc.Core.Tests
                     await requestStream.ToListAsync();
                 });
 
+                var server = helper.GetServer();
+                server.Start();
+                var channel = helper.GetChannel();
+
                 var call = Calls.AsyncDuplexStreamingCall(helper.CreateDuplexStreamingCall());
                 readyToShutdown.Task.Wait();  // make sure handler is running
             }

src/csharp/Grpc.Core.Tests/UserAgentStringTest.cs

@@ -63,10 +63,6 @@ namespace Grpc.Core.Tests
         public void DefaultUserAgentString()
         {
             helper = new MockServiceHelper(Host);
-            server = helper.GetServer();
-            server.Start();
-            channel = helper.GetChannel();
-
             helper.UnaryHandler = new UnaryServerMethod<string, string>((request, context) =>
             {
                 var userAgentString = context.RequestHeaders.First(m => (m.Key == "user-agent")).Value;
@@ -75,6 +71,11 @@ namespace Grpc.Core.Tests
                 Assert.IsTrue(parts[1].StartsWith("grpc-c/"));
                 return Task.FromResult("PASS");
             });
+
+            server = helper.GetServer();
+            server.Start();
+            channel = helper.GetChannel();
+
             Assert.AreEqual("PASS", Calls.BlockingUnaryCall(helper.CreateUnaryCall(), ""));
         }
 
@@ -83,11 +84,6 @@ namespace Grpc.Core.Tests
         {
             helper = new MockServiceHelper(Host,
                 channelOptions: new[] { new ChannelOption(ChannelOptions.PrimaryUserAgentString, "XYZ") });
-            server = helper.GetServer();
-            server.Start();
-            channel = helper.GetChannel();
-            
-            channel = helper.GetChannel();
             helper.UnaryHandler = new UnaryServerMethod<string, string>((request, context) =>
             {
                 var userAgentString = context.RequestHeaders.First(m => (m.Key == "user-agent")).Value;
@@ -95,6 +91,11 @@ namespace Grpc.Core.Tests
                 Assert.AreEqual("XYZ", parts[0]);
                 return Task.FromResult("PASS");
             });
+
+            server = helper.GetServer();
+            server.Start();
+            channel = helper.GetChannel();
+
             Assert.AreEqual("PASS", Calls.BlockingUnaryCall(helper.CreateUnaryCall(), ""));
         }
     }

src/objective-c/BoringSSL.podspec

@@ -31,7 +31,7 @@
 
 Pod::Spec.new do |s|
   s.name     = 'BoringSSL'
-  version = '8.0'
+  version = '8.1'
   s.version  = version
   s.summary  = 'BoringSSL is a fork of OpenSSL that is designed to meet Google’s needs.'
   # Adapted from the homepage:
@@ -69,8 +69,9 @@ Pod::Spec.new do |s|
 
   s.source = {
     :git => 'https://boringssl.googlesource.com/boringssl',
-    :tag => "version_for_cocoapods_#{version}",
-    # :commit => '4fec04b48406111cb88fdd8d196253adc54f7a31',
+    # Restore this version name hack in the next version!!
+    # :tag => "version_for_cocoapods_#{version}",
+    :tag => "version_for_cocoapods_8.0",
   }
 
   name = 'openssl'
@@ -95,7 +96,7 @@ Pod::Spec.new do |s|
   # The module map and umbrella header created automatically by Cocoapods don't work for C libraries
   # like this one. The following file, and a correct umbrella header, are created on the fly by the
   # `prepare_command` of this pod.
-  s.module_map = 'include/openssl/module.modulemap'
+  s.module_map = 'include/openssl/BoringSSL.modulemap'
 
   # We don't need to inhibit all warnings; only -Wno-shorten-64-to-32. But Cocoapods' linter doesn't
   # want that for some reason.
@@ -112,6 +113,7 @@ Pod::Spec.new do |s|
   s.subspec 'Interface' do |ss|
     ss.header_mappings_dir = 'include/openssl'
     ss.source_files = 'include/openssl/*.h'
+    ss.exclude_files = 'include/openssl/arm_arch.h'
   end
   s.subspec 'Implementation' do |ss|
     ss.header_mappings_dir = '.'
@@ -148,11 +150,6 @@ Pod::Spec.new do |s|
       #include "ssl.h"
       #include "crypto.h"
       #include "aes.h"
-      /* The following macros are defined by base.h. The latter is the first file included by the
-         other headers. */
-      #if defined(OPENSSL_ARM) || defined(OPENSSL_AARCH64)
-      #  include "arm_arch.h"
-      #endif
       #include "asn1.h"
       #include "asn1_mac.h"
       #include "asn1t.h"
@@ -186,7 +183,7 @@ Pod::Spec.new do |s|
       #include "x509.h"
       #include "x509v3.h"
     EOF
-    cat > include/openssl/module.modulemap <<EOF
+    cat > include/openssl/BoringSSL.modulemap <<EOF
       framework module openssl {
         umbrella header "umbrella.h"
         export *

src/objective-c/tests/InteropTestsLocalCleartext.m

@@ -36,7 +36,11 @@
 
 #import "InteropTests.h"
 
-static NSString * const kLocalCleartextHost = @"localhost:5050";
+// The server address is derived from preprocessor macro, which is
+// in turn derived from environment variable of the same name.
+#define NSStringize_helper(x) #x
+#define NSStringize(x) @NSStringize_helper(x)
+static NSString * const kLocalCleartextHost = NSStringize(HOST_PORT_LOCAL);
 
 // The Protocol Buffers encoding overhead of local interop server. Acquired
 // by experiment. Adjust this when server's proto file changes.

src/objective-c/tests/InteropTestsLocalSSL.m

@@ -35,8 +35,11 @@
 #import <GRPCClient/internal_testing/GRPCCall+InternalTests.h>
 
 #import "InteropTests.h"
-
-static NSString * const kLocalSSLHost = @"localhost:5051";
+// The server address is derived from preprocessor macro, which is
+// in turn derived from environment variable of the same name.
+#define NSStringize_helper(x) #x
+#define NSStringize(x) @NSStringize_helper(x)
+static NSString * const kLocalSSLHost = NSStringize(HOST_PORT_LOCALSSL);
 
 // The Protocol Buffers encoding overhead of local interop server. Acquired
 // by experiment. Adjust this when server's proto file changes.

src/objective-c/tests/InteropTestsRemote.m

@@ -36,7 +36,11 @@
 
 #import "InteropTests.h"
 
-static NSString * const kRemoteSSLHost = @"grpc-test.sandbox.googleapis.com";
+// The server address is derived from preprocessor macro, which is
+// in turn derived from environment variable of the same name.
+#define NSStringize_helper(x) #x
+#define NSStringize(x) @NSStringize_helper(x)
+static NSString * const kRemoteSSLHost = NSStringize(HOST_PORT_REMOTE);
 
 // The Protocol Buffers encoding overhead of remote interop server. Acquired
 // by experiment. Adjust this when server's proto file changes.

src/objective-c/tests/InteropTestsRemoteWithCronet/InteropTestsRemoteWithCronet.m

@@ -39,7 +39,12 @@
 
 #import "InteropTests.h"
 
-static NSString * const kRemoteSSLHost = @"grpc-test.sandbox.googleapis.com";
+// The server address is derived from preprocessor macro, which is
+// in turn derived from environment variable of the same name.
+#define NSStringize_helper(x) #x
+#define NSStringize(x) @NSStringize_helper(x)
+static NSString * const kRemoteSSLHost = NSStringize(HOST_PORT_REMOTE);
+
 
 // The Protocol Buffers encoding overhead of remote interop server. Acquired
 // by experiment. Adjust this when server's proto file changes.

src/objective-c/tests/Tests.xcodeproj/project.pbxproj

@@ -1282,6 +1282,9 @@
 				GCC_PREPROCESSOR_DEFINITIONS = (
 					"DEBUG=1",
 					"$(inherited)",
+					"HOST_PORT_LOCALSSL=$(HOST_PORT_LOCALSSL)",
+					"HOST_PORT_LOCAL=$(HOST_PORT_LOCAL)",
+					"HOST_PORT_REMOTE=$(HOST_PORT_REMOTE)",
 				);
 				GCC_SYMBOLS_PRIVATE_EXTERN = NO;
 				GCC_TREAT_WARNINGS_AS_ERRORS = YES;
@@ -1565,6 +1568,7 @@
 				GCC_PREPROCESSOR_DEFINITIONS = (
 					"DEBUG=1",
 					"$(inherited)",
+					"HOST_PORT_REMOTE=$(HOST_PORT_REMOTE)",
 				);
 				GCC_SYMBOLS_PRIVATE_EXTERN = NO;
 				GCC_TREAT_WARNINGS_AS_ERRORS = YES;

src/objective-c/tests/run_tests.sh

@@ -59,6 +59,9 @@ xcodebuild \
     -workspace Tests.xcworkspace \
     -scheme AllTests \
     -destination name="iPhone 6" \
+    HOST_PORT_LOCALSSL=localhost:5051 \
+    HOST_PORT_LOCAL=localhost:5050 \
+    HOST_PORT_REMOTE=grpc-test.sandbox.googleapis.com \
     test | xcpretty
 
 echo "TIME:  $(date)"
@@ -84,4 +87,5 @@ xcodebuild \
     -workspace Tests.xcworkspace \
     -scheme InteropTestsRemoteWithCronet \
     -destination name="iPhone 6" \
+    HOST_PORT_REMOTE=grpc-test.sandbox.googleapis.com \
     test | xcpretty

src/proto/grpc/lb/v1/load_balancer.proto

@@ -45,6 +45,20 @@ message Duration {
   int32 nanos = 2;
 }
 
+message Timestamp {
+
+  // Represents seconds of UTC time since Unix epoch
+  // 1970-01-01T00:00:00Z. Must be from 0001-01-01T00:00:00Z to
+  // 9999-12-31T23:59:59Z inclusive.
+  int64 seconds = 1;
+
+  // Non-negative fractions of a second at nanosecond resolution. Negative
+  // second values with fractions must still have non-negative nanos values
+  // that count forward in time. Must be from 0 to 999,999,999
+  // inclusive.
+  int32 nanos = 2;
+}
+
 service LoadBalancer {
   // Bidirectional rpc to get a list of servers.
   rpc BalanceLoad(stream LoadBalanceRequest)
@@ -63,22 +77,37 @@ message LoadBalanceRequest {
 }
 
 message InitialLoadBalanceRequest {
-  // Name of load balanced service (IE, service.grpc.gslb.google.com). Its
+  // Name of load balanced service (IE, balancer.service.com)
   // length should be less than 256 bytes.
   string name = 1;
 }
 
 // Contains client level statistics that are useful to load balancing. Each
-// count should be reset to zero after reporting the stats.
+// count except the timestamp should be reset to zero after reporting the stats.
 message ClientStats {
-  // The total number of requests sent by the client since the last report.
-  int64 total_requests = 1;
+  // The timestamp of generating the report.
+  Timestamp timestamp = 1;
 
-  // The number of client rpc errors since the last report.
-  int64 client_rpc_errors = 2;
+  // The total number of RPCs that started.
+  int64 num_calls_started = 2;
 
-  // The number of dropped requests since the last report.
-  int64 dropped_requests = 3;
+  // The total number of RPCs that finished.
+  int64 num_calls_finished = 3;
+
+  // The total number of RPCs that were dropped by the client because of rate
+  // limiting.
+  int64 num_calls_finished_with_drop_for_rate_limiting = 4;
+
+  // The total number of RPCs that were dropped by the client because of load
+  // balancing.
+  int64 num_calls_finished_with_drop_for_load_balancing = 5;
+
+  // The total number of RPCs that failed to reach a server except dropped RPCs.
+  int64 num_calls_finished_with_client_failed_to_send = 6;
+
+  // The total number of RPCs that finished and are known to have been received
+  // by a server.
+  int64 num_calls_finished_known_received = 7;
 }
 
 message LoadBalanceResponse {
@@ -120,6 +149,10 @@ message ServerList {
   Duration expiration_interval = 3;
 }
 
+// Contains server information. When none of the [drop_for_*] fields are true,
+// use the other fields. When drop_for_rate_limiting is true, ignore all other
+// fields. Use drop_for_load_balancing only when it is true and
+// drop_for_rate_limiting is false.
 message Server {
   // A resolved address for the server, serialized in network-byte-order. It may
   // either be an IPv4 or IPv6 address.
@@ -137,6 +170,10 @@ message Server {
   string load_balance_token = 3;
 
   // Indicates whether this particular request should be dropped by the client
-  // when this server is chosen from the list.
-  bool drop_request = 4;
+  // for rate limiting.
+  bool drop_for_rate_limiting = 4;
+
+  // Indicates whether this particular request should be dropped by the client
+  // for load balancing.
+  bool drop_for_load_balancing = 5;
 }

src/ruby/ext/grpc/rb_grpc_imports.generated.c

@@ -110,7 +110,6 @@ grpc_channel_register_call_type grpc_channel_register_call_import;
 grpc_channel_create_registered_call_type grpc_channel_create_registered_call_import;
 grpc_call_start_batch_type grpc_call_start_batch_import;
 grpc_call_get_peer_type grpc_call_get_peer_import;
-grpc_call_set_load_reporting_cost_context_type grpc_call_set_load_reporting_cost_context_import;
 grpc_census_call_set_context_type grpc_census_call_set_context_import;
 grpc_census_call_get_context_type grpc_census_call_get_context_import;
 grpc_channel_get_target_type grpc_channel_get_target_import;
@@ -407,7 +406,6 @@ void grpc_rb_load_imports(HMODULE library) {
   grpc_channel_create_registered_call_import = (grpc_channel_create_registered_call_type) GetProcAddress(library, "grpc_channel_create_registered_call");
   grpc_call_start_batch_import = (grpc_call_start_batch_type) GetProcAddress(library, "grpc_call_start_batch");
   grpc_call_get_peer_import = (grpc_call_get_peer_type) GetProcAddress(library, "grpc_call_get_peer");
-  grpc_call_set_load_reporting_cost_context_import = (grpc_call_set_load_reporting_cost_context_type) GetProcAddress(library, "grpc_call_set_load_reporting_cost_context");
   grpc_census_call_set_context_import = (grpc_census_call_set_context_type) GetProcAddress(library, "grpc_census_call_set_context");
   grpc_census_call_get_context_import = (grpc_census_call_get_context_type) GetProcAddress(library, "grpc_census_call_get_context");
   grpc_channel_get_target_import = (grpc_channel_get_target_type) GetProcAddress(library, "grpc_channel_get_target");

src/ruby/ext/grpc/rb_grpc_imports.generated.h

@@ -281,9 +281,6 @@ extern grpc_call_start_batch_type grpc_call_start_batch_import;
 typedef char *(*grpc_call_get_peer_type)(grpc_call *call);
 extern grpc_call_get_peer_type grpc_call_get_peer_import;
 #define grpc_call_get_peer grpc_call_get_peer_import
-typedef void(*grpc_call_set_load_reporting_cost_context_type)(grpc_call *call, struct grpc_load_reporting_cost_context *context);
-extern grpc_call_set_load_reporting_cost_context_type grpc_call_set_load_reporting_cost_context_import;
-#define grpc_call_set_load_reporting_cost_context grpc_call_set_load_reporting_cost_context_import
 typedef void(*grpc_census_call_set_context_type)(grpc_call *call, struct census_context *context);
 extern grpc_census_call_set_context_type grpc_census_call_set_context_import;
 #define grpc_census_call_set_context grpc_census_call_set_context_import

test/core/client_channel/parse_address_test.c

@@ -47,12 +47,12 @@
 
 #ifdef GRPC_HAVE_UNIX_SOCKET
 
-static void test_parse_unix(const char *uri_text, const char *pathname) {
+static void test_grpc_parse_unix(const char *uri_text, const char *pathname) {
   grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
   grpc_uri *uri = grpc_uri_parse(&exec_ctx, uri_text, 0);
   grpc_resolved_address addr;
 
-  GPR_ASSERT(1 == parse_unix(uri, &addr));
+  GPR_ASSERT(1 == grpc_parse_unix(uri, &addr));
   struct sockaddr_un *addr_un = (struct sockaddr_un *)addr.addr;
   GPR_ASSERT(AF_UNIX == addr_un->sun_family);
   GPR_ASSERT(0 == strcmp(addr_un->sun_path, pathname));
@@ -63,18 +63,18 @@ static void test_parse_unix(const char *uri_text, const char *pathname) {
 
 #else /* GRPC_HAVE_UNIX_SOCKET */
 
-static void test_parse_unix(const char *uri_text, const char *pathname) {}
+static void test_grpc_parse_unix(const char *uri_text, const char *pathname) {}
 
 #endif /* GRPC_HAVE_UNIX_SOCKET */
 
-static void test_parse_ipv4(const char *uri_text, const char *host,
+static void test_grpc_parse_ipv4(const char *uri_text, const char *host,
                                  unsigned short port) {
   grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
   grpc_uri *uri = grpc_uri_parse(&exec_ctx, uri_text, 0);
   grpc_resolved_address addr;
   char ntop_buf[INET_ADDRSTRLEN];
 
-  GPR_ASSERT(1 == parse_ipv4(uri, &addr));
+  GPR_ASSERT(1 == grpc_parse_ipv4(uri, &addr));
   struct sockaddr_in *addr_in = (struct sockaddr_in *)addr.addr;
   GPR_ASSERT(AF_INET == addr_in->sin_family);
   GPR_ASSERT(NULL != grpc_inet_ntop(AF_INET, &addr_in->sin_addr, ntop_buf,
@@ -86,14 +86,14 @@ static void test_parse_ipv4(const char *uri_text, const char *host,
   grpc_exec_ctx_finish(&exec_ctx);
 }
 
-static void test_parse_ipv6(const char *uri_text, const char *host,
+static void test_grpc_parse_ipv6(const char *uri_text, const char *host,
                                  unsigned short port, uint32_t scope_id) {
   grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
   grpc_uri *uri = grpc_uri_parse(&exec_ctx, uri_text, 0);
   grpc_resolved_address addr;
   char ntop_buf[INET6_ADDRSTRLEN];
 
-  GPR_ASSERT(1 == parse_ipv6(uri, &addr));
+  GPR_ASSERT(1 == grpc_parse_ipv6(uri, &addr));
   struct sockaddr_in6 *addr_in6 = (struct sockaddr_in6 *)addr.addr;
   GPR_ASSERT(AF_INET6 == addr_in6->sin6_family);
   GPR_ASSERT(NULL != grpc_inet_ntop(AF_INET6, &addr_in6->sin6_addr, ntop_buf,
@@ -109,8 +109,8 @@ static void test_parse_ipv6(const char *uri_text, const char *host,
 int main(int argc, char **argv) {
   grpc_test_init(argc, argv);
 
-  test_parse_unix("unix:/path/name", "/path/name");
-  test_parse_ipv4("ipv4:192.0.2.1:12345", "192.0.2.1", 12345);
-  test_parse_ipv6("ipv6:[2001:db8::1]:12345", "2001:db8::1", 12345, 0);
-  test_parse_ipv6("ipv6:[2001:db8::1%252]:12345", "2001:db8::1", 12345, 2);
+  test_grpc_parse_unix("unix:/path/name", "/path/name");
+  test_grpc_parse_ipv4("ipv4:192.0.2.1:12345", "192.0.2.1", 12345);
+  test_grpc_parse_ipv6("ipv6:[2001:db8::1]:12345", "2001:db8::1", 12345, 0);
+  test_grpc_parse_ipv6("ipv6:[2001:db8::1%252]:12345", "2001:db8::1", 12345, 2);
 }

test/core/client_channel/resolvers/BUILD

@@ -32,20 +32,48 @@ licenses(["notice"])  # 3-clause BSD
 cc_test(
     name = "dns_resolver_connectivity_test",
     srcs = ["dns_resolver_connectivity_test.c"],
-    deps = ["//:grpc", "//test/core/util:grpc_test_util", "//:gpr", "//test/core/util:gpr_test_util"],
-    copts = ['-std=c99']
+    copts = ["-std=c99"],
+    deps = [
+        "//:gpr",
+        "//:grpc",
+        "//test/core/util:gpr_test_util",
+        "//test/core/util:grpc_test_util",
+    ],
 )
 
 cc_test(
     name = "dns_resolver_test",
     srcs = ["dns_resolver_test.c"],
-    deps = ["//:grpc", "//test/core/util:grpc_test_util", "//:gpr", "//test/core/util:gpr_test_util"],
-    copts = ['-std=c99']
+    copts = ["-std=c99"],
+    deps = [
+        "//:gpr",
+        "//:grpc",
+        "//test/core/util:gpr_test_util",
+        "//test/core/util:grpc_test_util",
+    ],
 )
 
 cc_test(
     name = "sockaddr_resolver_test",
     srcs = ["sockaddr_resolver_test.c"],
-    deps = ["//:grpc", "//test/core/util:grpc_test_util", "//:gpr", "//test/core/util:gpr_test_util"],
-    copts = ['-std=c99']
+    copts = ["-std=c99"],
+    deps = [
+        "//:gpr",
+        "//:grpc",
+        "//test/core/util:gpr_test_util",
+        "//test/core/util:grpc_test_util",
+    ],
+)
+
+cc_test(
+    name = "fake_resolver_test",
+    srcs = ["fake_resolver_test.c"],
+    copts = ["-std=c99"],
+    deps = [
+        "//:gpr",
+        "//:grpc",
+        "//test/core/end2end:fake_resolver",
+        "//test/core/util:gpr_test_util",
+        "//test/core/util:grpc_test_util",
+    ],
 )

test/core/client_channel/resolvers/fake_resolver_test.c

@@ -0,0 +1,187 @@
+/*
+ *
+ * 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 <string.h>
+
+#include <grpc/support/alloc.h>
+#include <grpc/support/log.h>
+#include <grpc/support/string_util.h>
+
+#include "src/core/ext/filters/client_channel/lb_policy_factory.h"
+#include "src/core/ext/filters/client_channel/parse_address.h"
+#include "src/core/ext/filters/client_channel/resolver_registry.h"
+#include "src/core/lib/channel/channel_args.h"
+#include "src/core/lib/iomgr/combiner.h"
+#include "src/core/lib/security/credentials/fake/fake_credentials.h"
+
+#include "test/core/end2end/fake_resolver.h"
+#include "test/core/util/test_config.h"
+
+static grpc_resolver *build_fake_resolver(
+    grpc_exec_ctx *exec_ctx, grpc_combiner *combiner,
+    grpc_fake_resolver_response_generator *response_generator) {
+  grpc_resolver_factory *factory = grpc_resolver_factory_lookup("test");
+  grpc_arg generator_arg =
+      grpc_fake_resolver_response_generator_arg(response_generator);
+  grpc_resolver_args args;
+  memset(&args, 0, sizeof(args));
+  grpc_channel_args channel_args = {1, &generator_arg};
+  args.args = &channel_args;
+  args.combiner = combiner;
+  grpc_resolver *resolver =
+      grpc_resolver_factory_create_resolver(exec_ctx, factory, &args);
+  grpc_resolver_factory_unref(factory);
+  return resolver;
+}
+
+typedef struct on_resolution_arg {
+  grpc_channel_args *resolver_result;
+  grpc_channel_args *expected_resolver_result;
+  bool was_called;
+} on_resolution_arg;
+
+void on_resolution_cb(grpc_exec_ctx *exec_ctx, void *arg, grpc_error *error) {
+  on_resolution_arg *res = arg;
+  res->was_called = true;
+  // We only check the addresses channel arg because that's the only one
+  // explicitly set by the test via
+  // grpc_fake_resolver_response_generator_set_response.
+  const grpc_lb_addresses *actual_lb_addresses =
+      grpc_lb_addresses_find_channel_arg(res->resolver_result);
+  const grpc_lb_addresses *expected_lb_addresses =
+      grpc_lb_addresses_find_channel_arg(res->expected_resolver_result);
+  GPR_ASSERT(
+      grpc_lb_addresses_cmp(actual_lb_addresses, expected_lb_addresses) == 0);
+  grpc_channel_args_destroy(exec_ctx, res->resolver_result);
+  grpc_channel_args_destroy(exec_ctx, res->expected_resolver_result);
+}
+
+static void test_fake_resolver() {
+  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
+  grpc_combiner *combiner = grpc_combiner_create(NULL);
+  // Create resolver.
+  grpc_fake_resolver_response_generator *response_generator =
+      grpc_fake_resolver_response_generator_create();
+  grpc_resolver *resolver =
+      build_fake_resolver(&exec_ctx, combiner, response_generator);
+  GPR_ASSERT(resolver != NULL);
+
+  // Setup expectations.
+  grpc_uri *uris[] = {grpc_uri_parse(&exec_ctx, "ipv4:10.2.1.1:1234", true),
+                      grpc_uri_parse(&exec_ctx, "ipv4:127.0.0.1:4321", true)};
+  char *balancer_names[] = {"name1", "name2"};
+  const bool is_balancer[] = {true, false};
+  grpc_lb_addresses *addresses = grpc_lb_addresses_create(3, NULL);
+  for (size_t i = 0; i < GPR_ARRAY_SIZE(uris); ++i) {
+    grpc_lb_addresses_set_address_from_uri(
+        addresses, i, uris[i], is_balancer[i], balancer_names[i], NULL);
+    grpc_uri_destroy(uris[i]);
+  }
+  const grpc_arg addresses_arg =
+      grpc_lb_addresses_create_channel_arg(addresses);
+  grpc_channel_args *results =
+      grpc_channel_args_copy_and_add(NULL, &addresses_arg, 1);
+  grpc_lb_addresses_destroy(&exec_ctx, addresses);
+  on_resolution_arg on_res_arg;
+  memset(&on_res_arg, 0, sizeof(on_res_arg));
+  on_res_arg.expected_resolver_result = results;
+  grpc_closure *on_resolution = grpc_closure_create(
+      on_resolution_cb, &on_res_arg, grpc_combiner_scheduler(combiner, false));
+
+  // Set resolver results and trigger first resolution. on_resolution_cb
+  // performs the checks.
+  grpc_fake_resolver_response_generator_set_response(
+      &exec_ctx, response_generator, results);
+  grpc_resolver_next_locked(&exec_ctx, resolver, &on_res_arg.resolver_result,
+                            on_resolution);
+  grpc_exec_ctx_flush(&exec_ctx);
+  GPR_ASSERT(on_res_arg.was_called);
+
+  // Setup update.
+  grpc_uri *uris_update[] = {
+      grpc_uri_parse(&exec_ctx, "ipv4:192.168.1.0:31416", true)};
+  char *balancer_names_update[] = {"name3"};
+  const bool is_balancer_update[] = {false};
+  grpc_lb_addresses *addresses_update = grpc_lb_addresses_create(1, NULL);
+  for (size_t i = 0; i < GPR_ARRAY_SIZE(uris_update); ++i) {
+    grpc_lb_addresses_set_address_from_uri(addresses_update, i, uris_update[i],
+                                           is_balancer_update[i],
+                                           balancer_names_update[i], NULL);
+    grpc_uri_destroy(uris_update[i]);
+  }
+
+  grpc_arg addresses_update_arg =
+      grpc_lb_addresses_create_channel_arg(addresses_update);
+  grpc_channel_args *results_update =
+      grpc_channel_args_copy_and_add(NULL, &addresses_update_arg, 1);
+  grpc_lb_addresses_destroy(&exec_ctx, addresses_update);
+
+  // Setup expectations for the update.
+  on_resolution_arg on_res_arg_update;
+  memset(&on_res_arg_update, 0, sizeof(on_res_arg_update));
+  on_res_arg_update.expected_resolver_result = results_update;
+  on_resolution = grpc_closure_create(on_resolution_cb, &on_res_arg_update,
+                                      grpc_combiner_scheduler(combiner, false));
+
+  // Set updated resolver results and trigger a second resolution.
+  grpc_fake_resolver_response_generator_set_response(
+      &exec_ctx, response_generator, results_update);
+  grpc_resolver_next_locked(&exec_ctx, resolver,
+                            &on_res_arg_update.resolver_result, on_resolution);
+  grpc_exec_ctx_flush(&exec_ctx);
+  GPR_ASSERT(on_res_arg.was_called);
+
+  // Requesting a new resolution without re-senting the response shouldn't
+  // trigger the resolution callback.
+  memset(&on_res_arg, 0, sizeof(on_res_arg));
+  grpc_resolver_next_locked(&exec_ctx, resolver, &on_res_arg.resolver_result,
+                            on_resolution);
+  grpc_exec_ctx_flush(&exec_ctx);
+  GPR_ASSERT(!on_res_arg.was_called);
+
+  GRPC_COMBINER_UNREF(&exec_ctx, combiner, "test_fake_resolver");
+  GRPC_RESOLVER_UNREF(&exec_ctx, resolver, "test_fake_resolver");
+  grpc_exec_ctx_finish(&exec_ctx);
+  grpc_fake_resolver_response_generator_unref(response_generator);
+}
+
+int main(int argc, char **argv) {
+  grpc_test_init(argc, argv);
+  grpc_fake_resolver_init();  // Registers the "test" scheme.
+  grpc_init();
+
+  test_fake_resolver();
+
+  grpc_shutdown();
+  return 0;
+}

test/core/end2end/BUILD

@@ -32,49 +32,66 @@ licenses(["notice"])  # 3-clause BSD
 load(":generate_tests.bzl", "grpc_end2end_tests")
 
 cc_library(
-  name = 'cq_verifier',
-  srcs = ['cq_verifier.c'],
-  hdrs = ['cq_verifier.h'],
-  deps = ['//:gpr', '//:grpc', '//test/core/util:grpc_test_util'],
-  copts = ['-std=c99'],
+    name = "cq_verifier",
+    srcs = ["cq_verifier.c"],
+    hdrs = ["cq_verifier.h"],
+    copts = ["-std=c99"],
     visibility = ["//test:__subpackages__"],
+    deps = [
+        "//:gpr",
+        "//:grpc",
+        "//test/core/util:grpc_test_util",
+    ],
 )
 
 cc_library(
-  name = 'ssl_test_data',
-  visibility = ["//test:__subpackages__"],
-  hdrs = ['data/ssl_test_data.h'],
-  copts = ['-std=c99'],
+    name = "ssl_test_data",
     srcs = [
         "data/client_certs.c",
         "data/server1_cert.c",
         "data/server1_key.c",
         "data/test_root_cert.c",
-  ]
+    ],
+    hdrs = ["data/ssl_test_data.h"],
+    copts = ["-std=c99"],
+    visibility = ["//test:__subpackages__"],
 )
 
 cc_library(
-  name = 'fake_resolver',
-  hdrs = ['fake_resolver.h'],
-  srcs = ['fake_resolver.c'],
-  copts = ['-std=c99'],
-  deps = ['//:gpr', '//:grpc', '//test/core/util:grpc_test_util']
+    name = "fake_resolver",
+    srcs = ["fake_resolver.c"],
+    hdrs = ["fake_resolver.h"],
+    copts = ["-std=c99"],
+    visibility = ["//test:__subpackages__"],
+    deps = [
+        "//:gpr",
+        "//:grpc",
+        "//test/core/util:grpc_test_util",
+    ],
 )
 
 cc_library(
-  name = 'http_proxy',
-  hdrs = ['fixtures/http_proxy_fixture.h'],
-  srcs = ['fixtures/http_proxy_fixture.c'],
-  copts = ['-std=c99'],
-  deps = ['//:gpr', '//:grpc', '//test/core/util:grpc_test_util']
+    name = "http_proxy",
+    srcs = ["fixtures/http_proxy_fixture.c"],
+    hdrs = ["fixtures/http_proxy_fixture.h"],
+    copts = ["-std=c99"],
+    deps = [
+        "//:gpr",
+        "//:grpc",
+        "//test/core/util:grpc_test_util",
+    ],
 )
 
 cc_library(
-  name = 'proxy',
-  hdrs = ['fixtures/proxy.h'],
-  srcs = ['fixtures/proxy.c'],
-  copts = ['-std=c99'],
-  deps = ['//:gpr', '//:grpc', '//test/core/util:grpc_test_util']
+    name = "proxy",
+    srcs = ["fixtures/proxy.c"],
+    hdrs = ["fixtures/proxy.h"],
+    copts = ["-std=c99"],
+    deps = [
+        "//:gpr",
+        "//:grpc",
+        "//test/core/util:grpc_test_util",
+    ],
 )
 
 grpc_end2end_tests()

test/core/end2end/fake_resolver.c

@@ -32,6 +32,7 @@
 // This is similar to the sockaddr resolver, except that it supports a
 // bunch of query args that are useful for dependency injection in tests.
 
+#include <limits.h>
 #include <stdbool.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -46,12 +47,18 @@
 #include "src/core/ext/filters/client_channel/parse_address.h"
 #include "src/core/ext/filters/client_channel/resolver_registry.h"
 #include "src/core/lib/channel/channel_args.h"
+#include "src/core/lib/iomgr/combiner.h"
 #include "src/core/lib/iomgr/resolve_address.h"
 #include "src/core/lib/iomgr/unix_sockets_posix.h"
 #include "src/core/lib/slice/slice_internal.h"
 #include "src/core/lib/slice/slice_string_helpers.h"
 #include "src/core/lib/support/string.h"
 
+#include "test/core/end2end/fake_resolver.h"
+
+#define GRPC_ARG_FAKE_RESOLVER_RESPONSE_GENERATOR \
+  "grpc.fake_resolver.response_generator"
+
 //
 // fake_resolver
 //
@@ -62,12 +69,11 @@ typedef struct {
 
   // passed-in parameters
   grpc_channel_args* channel_args;
-  grpc_lb_addresses* addresses;
 
-  // mutex guarding the rest of the state
-  gpr_mu mu;
-  // have we published?
-  bool published;
+  // If not NULL, the next set of resolution results to be returned to
+  // grpc_resolver_next_locked()'s closure.
+  grpc_channel_args* next_results;
+
   // pending next completion, or NULL
   grpc_closure* next_completion;
   // target result address for next completion
@@ -76,60 +82,137 @@ typedef struct {
 
 static void fake_resolver_destroy(grpc_exec_ctx* exec_ctx, grpc_resolver* gr) {
   fake_resolver* r = (fake_resolver*)gr;
-  gpr_mu_destroy(&r->mu);
+  grpc_channel_args_destroy(exec_ctx, r->next_results);
   grpc_channel_args_destroy(exec_ctx, r->channel_args);
-  grpc_lb_addresses_destroy(exec_ctx, r->addresses);
   gpr_free(r);
 }
 
-static void fake_resolver_shutdown(grpc_exec_ctx* exec_ctx,
+static void fake_resolver_shutdown_locked(grpc_exec_ctx* exec_ctx,
                                           grpc_resolver* resolver) {
   fake_resolver* r = (fake_resolver*)resolver;
-  gpr_mu_lock(&r->mu);
   if (r->next_completion != NULL) {
     *r->target_result = NULL;
     grpc_closure_sched(exec_ctx, r->next_completion, GRPC_ERROR_NONE);
     r->next_completion = NULL;
   }
-  gpr_mu_unlock(&r->mu);
 }
 
 static void fake_resolver_maybe_finish_next_locked(grpc_exec_ctx* exec_ctx,
                                                    fake_resolver* r) {
-  if (r->next_completion != NULL && !r->published) {
-    r->published = true;
-    grpc_arg arg = grpc_lb_addresses_create_channel_arg(r->addresses);
+  if (r->next_completion != NULL && r->next_results != NULL) {
     *r->target_result =
-        grpc_channel_args_copy_and_add(r->channel_args, &arg, 1);
+        grpc_channel_args_merge(r->channel_args, r->next_results);
+    grpc_channel_args_destroy(exec_ctx, r->next_results);
     grpc_closure_sched(exec_ctx, r->next_completion, GRPC_ERROR_NONE);
     r->next_completion = NULL;
+    r->next_results = NULL;
   }
 }
 
-static void fake_resolver_channel_saw_error(grpc_exec_ctx* exec_ctx,
+static void fake_resolver_channel_saw_error_locked(grpc_exec_ctx* exec_ctx,
                                                    grpc_resolver* resolver) {
   fake_resolver* r = (fake_resolver*)resolver;
-  gpr_mu_lock(&r->mu);
-  r->published = false;
   fake_resolver_maybe_finish_next_locked(exec_ctx, r);
-  gpr_mu_unlock(&r->mu);
 }
 
-static void fake_resolver_next(grpc_exec_ctx* exec_ctx, grpc_resolver* resolver,
+static void fake_resolver_next_locked(grpc_exec_ctx* exec_ctx,
+                                      grpc_resolver* resolver,
                                       grpc_channel_args** target_result,
                                       grpc_closure* on_complete) {
   fake_resolver* r = (fake_resolver*)resolver;
-  gpr_mu_lock(&r->mu);
   GPR_ASSERT(!r->next_completion);
   r->next_completion = on_complete;
   r->target_result = target_result;
   fake_resolver_maybe_finish_next_locked(exec_ctx, r);
-  gpr_mu_unlock(&r->mu);
 }
 
 static const grpc_resolver_vtable fake_resolver_vtable = {
-    fake_resolver_destroy, fake_resolver_shutdown,
-    fake_resolver_channel_saw_error, fake_resolver_next};
+    fake_resolver_destroy, fake_resolver_shutdown_locked,
+    fake_resolver_channel_saw_error_locked, fake_resolver_next_locked};
+
+struct grpc_fake_resolver_response_generator {
+  fake_resolver* resolver;  // Set by the fake_resolver constructor to itself.
+  grpc_channel_args* next_response;
+  gpr_refcount refcount;
+};
+
+grpc_fake_resolver_response_generator*
+grpc_fake_resolver_response_generator_create() {
+  grpc_fake_resolver_response_generator* generator =
+      gpr_zalloc(sizeof(*generator));
+  gpr_ref_init(&generator->refcount, 1);
+  return generator;
+}
+
+grpc_fake_resolver_response_generator*
+grpc_fake_resolver_response_generator_ref(
+    grpc_fake_resolver_response_generator* generator) {
+  gpr_ref(&generator->refcount);
+  return generator;
+}
+
+void grpc_fake_resolver_response_generator_unref(
+    grpc_fake_resolver_response_generator* generator) {
+  if (gpr_unref(&generator->refcount)) {
+    gpr_free(generator);
+  }
+}
+
+static void set_response_cb(grpc_exec_ctx* exec_ctx, void* arg,
+                            grpc_error* error) {
+  grpc_fake_resolver_response_generator* generator = arg;
+  fake_resolver* r = generator->resolver;
+  if (r->next_results != NULL) {
+    grpc_channel_args_destroy(exec_ctx, r->next_results);
+  }
+  r->next_results = generator->next_response;
+  fake_resolver_maybe_finish_next_locked(exec_ctx, r);
+}
+
+void grpc_fake_resolver_response_generator_set_response(
+    grpc_exec_ctx* exec_ctx, grpc_fake_resolver_response_generator* generator,
+    grpc_channel_args* next_response) {
+  GPR_ASSERT(generator->resolver != NULL);
+  generator->next_response = grpc_channel_args_copy(next_response);
+  grpc_closure_sched(
+      exec_ctx,
+      grpc_closure_create(
+          set_response_cb, generator,
+          grpc_combiner_scheduler(generator->resolver->base.combiner, false)),
+      GRPC_ERROR_NONE);
+}
+
+static void* response_generator_arg_copy(void* p) {
+  return grpc_fake_resolver_response_generator_ref(p);
+}
+
+static void response_generator_arg_destroy(grpc_exec_ctx* exec_ctx, void* p) {
+  grpc_fake_resolver_response_generator_unref(p);
+}
+
+static int response_generator_cmp(void* a, void* b) { return GPR_ICMP(a, b); }
+
+static const grpc_arg_pointer_vtable response_generator_arg_vtable = {
+    response_generator_arg_copy, response_generator_arg_destroy,
+    response_generator_cmp};
+
+grpc_arg grpc_fake_resolver_response_generator_arg(
+    grpc_fake_resolver_response_generator* generator) {
+  grpc_arg arg;
+  arg.type = GRPC_ARG_POINTER;
+  arg.key = GRPC_ARG_FAKE_RESOLVER_RESPONSE_GENERATOR;
+  arg.value.pointer.p = generator;
+  arg.value.pointer.vtable = &response_generator_arg_vtable;
+  return arg;
+}
+
+grpc_fake_resolver_response_generator*
+grpc_fake_resolver_get_response_generator(const grpc_channel_args* args) {
+  const grpc_arg* arg =
+      grpc_channel_args_find(args, GRPC_ARG_FAKE_RESOLVER_RESPONSE_GENERATOR);
+  if (arg == NULL || arg->type != GRPC_ARG_POINTER) return NULL;
+  return arg->value.pointer.p;
+}
 
 //
 // fake_resolver_factory
@@ -139,81 +222,15 @@ static void fake_resolver_factory_ref(grpc_resolver_factory* factory) {}
 
 static void fake_resolver_factory_unref(grpc_resolver_factory* factory) {}
 
-static void do_nothing(void* ignored) {}
-
 static grpc_resolver* fake_resolver_create(grpc_exec_ctx* exec_ctx,
                                            grpc_resolver_factory* factory,
                                            grpc_resolver_args* args) {
-  if (0 != strcmp(args->uri->authority, "")) {
-    gpr_log(GPR_ERROR, "authority based uri's not supported by the %s scheme",
-            args->uri->scheme);
-    return NULL;
-  }
-  // Get lb_enabled arg.  Anything other than "0" is interpreted as true.
-  const char* lb_enabled_qpart =
-      grpc_uri_get_query_arg(args->uri, "lb_enabled");
-  const bool lb_enabled =
-      lb_enabled_qpart != NULL && strcmp("0", lb_enabled_qpart) != 0;
-
-  // Get the balancer's names.
-  const char* balancer_names =
-      grpc_uri_get_query_arg(args->uri, "balancer_names");
-  grpc_slice_buffer balancer_names_parts;
-  grpc_slice_buffer_init(&balancer_names_parts);
-  if (balancer_names != NULL) {
-    const grpc_slice balancer_names_slice =
-        grpc_slice_from_copied_string(balancer_names);
-    grpc_slice_split(balancer_names_slice, ",", &balancer_names_parts);
-    grpc_slice_unref(balancer_names_slice);
-  }
-
-  // Construct addresses.
-  grpc_slice path_slice =
-      grpc_slice_new(args->uri->path, strlen(args->uri->path), do_nothing);
-  grpc_slice_buffer path_parts;
-  grpc_slice_buffer_init(&path_parts);
-  grpc_slice_split(path_slice, ",", &path_parts);
-  if (balancer_names_parts.count > 0 &&
-      path_parts.count != balancer_names_parts.count) {
-    gpr_log(GPR_ERROR,
-            "Balancer names present but mismatched with number of addresses: "
-            "%lu balancer names != %lu addresses",
-            (unsigned long)balancer_names_parts.count,
-            (unsigned long)path_parts.count);
-    return NULL;
-  }
-  grpc_lb_addresses* addresses =
-      grpc_lb_addresses_create(path_parts.count, NULL /* user_data_vtable */);
-  bool errors_found = false;
-  for (size_t i = 0; i < addresses->num_addresses; i++) {
-    grpc_uri ith_uri = *args->uri;
-    char* part_str = grpc_slice_to_c_string(path_parts.slices[i]);
-    ith_uri.path = part_str;
-    if (!parse_ipv4(&ith_uri, &addresses->addresses[i].address)) {
-      errors_found = true;
-    }
-    gpr_free(part_str);
-    if (errors_found) break;
-    addresses->addresses[i].is_balancer = lb_enabled;
-    addresses->addresses[i].balancer_name =
-        balancer_names_parts.count > 0
-            ? grpc_dump_slice(balancer_names_parts.slices[i], GPR_DUMP_ASCII)
-            : NULL;
-  }
-  grpc_slice_buffer_destroy_internal(exec_ctx, &path_parts);
-  grpc_slice_buffer_destroy_internal(exec_ctx, &balancer_names_parts);
-  grpc_slice_unref(path_slice);
-  if (errors_found) {
-    grpc_lb_addresses_destroy(exec_ctx, addresses);
-    return NULL;
-  }
-  // Instantiate resolver.
-  fake_resolver* r = gpr_malloc(sizeof(fake_resolver));
-  memset(r, 0, sizeof(*r));
+  fake_resolver* r = gpr_zalloc(sizeof(*r));
   r->channel_args = grpc_channel_args_copy(args->args);
-  r->addresses = addresses;
-  gpr_mu_init(&r->mu);
   grpc_resolver_init(&r->base, &fake_resolver_vtable, args->combiner);
+  grpc_fake_resolver_response_generator* response_generator =
+      grpc_fake_resolver_get_response_generator(args->args);
+  if (response_generator != NULL) response_generator->resolver = r;
   return &r->base;
 }
 

test/core/end2end/fake_resolver.h

@@ -32,8 +32,42 @@
 #ifndef GRPC_TEST_CORE_END2END_FAKE_RESOLVER_H
 #define GRPC_TEST_CORE_END2END_FAKE_RESOLVER_H
 
+#include "src/core/ext/filters/client_channel/lb_policy_factory.h"
+#include "src/core/ext/filters/client_channel/uri_parser.h"
+#include "src/core/lib/channel/channel_args.h"
+
 #include "test/core/util/test_config.h"
 
 void grpc_fake_resolver_init();
 
+// Instances of \a grpc_fake_resolver_response_generator are passed to the
+// fake resolver in a channel argument (see \a
+// grpc_fake_resolver_response_generator_arg) in order to inject and trigger
+// custom resolutions. See also \a
+// grpc_fake_resolver_response_generator_set_response.
+typedef struct grpc_fake_resolver_response_generator
+    grpc_fake_resolver_response_generator;
+grpc_fake_resolver_response_generator*
+grpc_fake_resolver_response_generator_create();
+
+// Instruct the fake resolver associated with the \a response_generator instance
+// to trigger a new resolution for \a uri and \a args.
+void grpc_fake_resolver_response_generator_set_response(
+    grpc_exec_ctx* exec_ctx, grpc_fake_resolver_response_generator* generator,
+    grpc_channel_args* next_response);
+
+// Return a \a grpc_arg for a \a grpc_fake_resolver_response_generator instance.
+grpc_arg grpc_fake_resolver_response_generator_arg(
+    grpc_fake_resolver_response_generator* generator);
+// Return the \a grpc_fake_resolver_response_generator instance in \a args or
+// NULL.
+grpc_fake_resolver_response_generator*
+grpc_fake_resolver_get_response_generator(const grpc_channel_args* args);
+
+grpc_fake_resolver_response_generator*
+grpc_fake_resolver_response_generator_ref(
+    grpc_fake_resolver_response_generator* generator);
+void grpc_fake_resolver_response_generator_unref(
+    grpc_fake_resolver_response_generator* generator);
+
 #endif /* GRPC_TEST_CORE_END2END_FAKE_RESOLVER_H */

test/core/end2end/fuzzers/api_fuzzer.c

@@ -932,6 +932,9 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
         }
         uint32_t propagation_mask = read_uint32(&inp);
         grpc_slice method = read_string_like_slice(&inp);
+        if (GRPC_SLICE_LENGTH(method) == 0) {
+          ok = false;
+        }
         grpc_slice host = read_string_like_slice(&inp);
         gpr_timespec deadline =
             gpr_time_add(gpr_now(GPR_CLOCK_REALTIME),

test/core/end2end/fuzzers/hpack.dictionary

@@ -77,6 +77,7 @@
 "\x08if-range"
 "\x13if-unmodified-since"
 "\x0Dlast-modified"
+"\x0Blb-cost-bin"
 "\x04link"
 "\x08location"
 "\x0Cmax-forwards"
@@ -153,6 +154,7 @@
 "\x00\x13if-unmodified-since\x00"
 "\x00\x0Dlast-modified\x00"
 "\x00\x08lb-token\x00"
+"\x00\x0Blb-cost-bin\x00"
 "\x00\x04link\x00"
 "\x00\x08location\x00"
 "\x00\x0Cmax-forwards\x00"

test/core/end2end/tests/keepalive_timeout.c

@@ -190,8 +190,6 @@ static void test_keepalive_timeout(grpc_end2end_test_config config) {
   GPR_ASSERT(GRPC_CALL_OK == error);
 
   CQ_EXPECT_COMPLETION(cqv, tag(102), 1);
-  cq_verify(cqv);
-
   CQ_EXPECT_COMPLETION(cqv, tag(1), 1);
   cq_verify(cqv);
 

test/core/end2end/tests/load_reporting_hook.c

@@ -129,8 +129,7 @@ static void end_test(grpc_end2end_test_fixture *f) {
 static void request_response_with_payload(
     grpc_end2end_test_config config, grpc_end2end_test_fixture f,
     const char *method_name, const char *request_msg, const char *response_msg,
-    grpc_metadata *initial_lr_metadata,
-    grpc_load_reporting_cost_context *cost_ctx) {
+    grpc_metadata *initial_lr_metadata, grpc_metadata *trailing_lr_metadata) {
   grpc_slice request_payload_slice = grpc_slice_from_static_string(request_msg);
   grpc_slice response_payload_slice =
       grpc_slice_from_static_string(response_msg);
@@ -243,8 +242,9 @@ static void request_response_with_payload(
   op->reserved = NULL;
   op++;
   op->op = GRPC_OP_SEND_STATUS_FROM_SERVER;
-  GPR_ASSERT(cost_ctx != NULL);
-  grpc_call_set_load_reporting_cost_context(s, cost_ctx);
+  GPR_ASSERT(trailing_lr_metadata != NULL);
+  op->data.send_status_from_server.trailing_metadata_count = 1;
+  op->data.send_status_from_server.trailing_metadata = trailing_lr_metadata;
   op->data.send_status_from_server.status = GRPC_STATUS_OK;
   grpc_slice status_details = grpc_slice_from_static_string("xyz");
   op->data.send_status_from_server.status_details = &status_details;
@@ -298,21 +298,21 @@ static void test_load_reporting_hook(grpc_end2end_test_config config) {
   const char *response_msg = "... and the response from the server";
 
   grpc_metadata initial_lr_metadata;
+  grpc_metadata trailing_lr_metadata;
 
   initial_lr_metadata.key = GRPC_MDSTR_LB_TOKEN;
   initial_lr_metadata.value = grpc_slice_from_static_string("client-token");
   memset(&initial_lr_metadata.internal_data, 0,
          sizeof(initial_lr_metadata.internal_data));
 
-  grpc_load_reporting_cost_context *cost_ctx = gpr_malloc(sizeof(*cost_ctx));
-  memset(cost_ctx, 0, sizeof(*cost_ctx));
-  cost_ctx->values_count = 1;
-  cost_ctx->values =
-      gpr_malloc(sizeof(*cost_ctx->values) * cost_ctx->values_count);
-  cost_ctx->values[0] = grpc_slice_from_static_string("cost-token");
+  trailing_lr_metadata.key = GRPC_MDSTR_LB_COST_BIN;
+  trailing_lr_metadata.value = grpc_slice_from_static_string("server-token");
+  memset(&trailing_lr_metadata.internal_data, 0,
+         sizeof(trailing_lr_metadata.internal_data));
 
   request_response_with_payload(config, f, method_name, request_msg,
-                                response_msg, &initial_lr_metadata, cost_ctx);
+                                response_msg, &initial_lr_metadata,
+                                &trailing_lr_metadata);
   end_test(&f);
   {
     grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;

test/core/end2end/tests/resource_quota_server.c

@@ -205,7 +205,7 @@ void resource_quota_server(grpc_end2end_test_config config) {
     op = ops;
     op->op = GRPC_OP_SEND_INITIAL_METADATA;
     op->data.send_initial_metadata.count = 0;
-    op->flags = 0;
+    op->flags = GRPC_INITIAL_METADATA_WAIT_FOR_READY;
     op->reserved = NULL;
     op++;
     op->op = GRPC_OP_SEND_MESSAGE;

test/core/end2end/tests/streaming_error_response.c

@@ -184,6 +184,9 @@ static void test(grpc_end2end_test_config config, bool request_status_early) {
   GPR_ASSERT(GRPC_CALL_OK == error);
 
   CQ_EXPECT_COMPLETION(cqv, tag(102), 1);
+  if (!request_status_early) {
+    CQ_EXPECT_COMPLETION(cqv, tag(1), 1);
+  }
   cq_verify(cqv);
 
   memset(ops, 0, sizeof(ops));
@@ -195,9 +198,6 @@ static void test(grpc_end2end_test_config config, bool request_status_early) {
   GPR_ASSERT(GRPC_CALL_OK == error);
 
   CQ_EXPECT_COMPLETION(cqv, tag(103), 1);
-  if (!request_status_early) {
-    CQ_EXPECT_COMPLETION(cqv, tag(1), 1);
-  }
   cq_verify(cqv);
 
   memset(ops, 0, sizeof(ops));

test/core/iomgr/udp_server_test.c

@@ -91,7 +91,7 @@ static void on_write(grpc_exec_ctx *exec_ctx, grpc_fd *emfd, void *user_data) {
 }
 
 static void on_fd_orphaned(grpc_exec_ctx *exec_ctx, grpc_fd *emfd,
-                           void *user_data) {
+                           grpc_closure *closure, void *user_data) {
   gpr_log(GPR_INFO, "gRPC FD about to be orphaned: %d",
           grpc_fd_wrapped_fd(emfd));
   g_number_of_orphan_calls++;
@@ -228,9 +228,9 @@ static void test_no_op_with_port_and_start(void) {
   grpc_udp_server_destroy(&exec_ctx, s, NULL);
   grpc_exec_ctx_finish(&exec_ctx);
 
-  /* The server had a single FD, which is orphaned once in *
-   * deactivated_all_ports, and once in grpc_udp_server_destroy. */
-  GPR_ASSERT(g_number_of_orphan_calls == 2);
+  /* The server had a single FD, which is orphaned exactly once in *
+   * grpc_udp_server_destroy. */
+  GPR_ASSERT(g_number_of_orphan_calls == 1);
 }
 
 static void test_receive(int number_of_clients) {
@@ -297,9 +297,9 @@ static void test_receive(int number_of_clients) {
   grpc_udp_server_destroy(&exec_ctx, s, NULL);
   grpc_exec_ctx_finish(&exec_ctx);
 
-  /* The server had a single FD, which is orphaned once in *
-   * deactivated_all_ports, and once in grpc_udp_server_destroy. */
-  GPR_ASSERT(g_number_of_orphan_calls == 2);
+  /* The server had a single FD, which is orphaned exactly once in *
+   * grpc_udp_server_destroy. */
+  GPR_ASSERT(g_number_of_orphan_calls == 1);
 
   /* The write callback should have fired a few times. */
   GPR_ASSERT(g_number_of_writes > 0);

test/cpp/grpclb/grpclb_api_test.cc

@@ -106,11 +106,13 @@ TEST_F(GrpclbTest, ParseResponseServerList) {
   auto* server = serverlist->add_servers();
   server->set_ip_address(Ip4ToPackedString("127.0.0.1"));
   server->set_port(12345);
-  server->set_drop_request(true);
+  server->set_drop_for_rate_limiting(true);
+  server->set_drop_for_load_balancing(false);
   server = response.mutable_server_list()->add_servers();
   server->set_ip_address(Ip4ToPackedString("10.0.0.1"));
   server->set_port(54321);
-  server->set_drop_request(false);
+  server->set_drop_for_rate_limiting(false);
+  server->set_drop_for_load_balancing(true);
   auto* expiration_interval = serverlist->mutable_expiration_interval();
   expiration_interval->set_seconds(888);
   expiration_interval->set_nanos(999);
@@ -125,12 +127,14 @@ TEST_F(GrpclbTest, ParseResponseServerList) {
   EXPECT_EQ(PackedStringToIp(c_serverlist->servers[0]->ip_address),
             "127.0.0.1");
   EXPECT_EQ(c_serverlist->servers[0]->port, 12345);
-  EXPECT_TRUE(c_serverlist->servers[0]->drop_request);
+  EXPECT_TRUE(c_serverlist->servers[0]->drop_for_rate_limiting);
+  EXPECT_FALSE(c_serverlist->servers[0]->drop_for_load_balancing);
   EXPECT_TRUE(c_serverlist->servers[1]->has_ip_address);
 
   EXPECT_EQ(PackedStringToIp(c_serverlist->servers[1]->ip_address), "10.0.0.1");
   EXPECT_EQ(c_serverlist->servers[1]->port, 54321);
-  EXPECT_FALSE(c_serverlist->servers[1]->drop_request);
+  EXPECT_FALSE(c_serverlist->servers[1]->drop_for_rate_limiting);
+  EXPECT_TRUE(c_serverlist->servers[1]->drop_for_load_balancing);
 
   EXPECT_TRUE(c_serverlist->expiration_interval.has_seconds);
   EXPECT_EQ(c_serverlist->expiration_interval.seconds, 888);

test/cpp/grpclb/grpclb_test.cc

@@ -573,34 +573,51 @@ static void perform_request(client_fixture *cf) {
 static void setup_client(const server_fixture *lb_server,
                          const server_fixture *backends, client_fixture *cf) {
   grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
-  char *lb_uri;
-  // The grpclb LB policy will be automatically selected by virtue of
-  // the fact that the returned addresses are balancer addresses.
-  gpr_asprintf(&lb_uri, "test:///%s?lb_enabled=1&balancer_names=%s",
-               lb_server->servers_hostport, lb_server->balancer_name);
-
-  grpc_arg expected_target_arg;
-  expected_target_arg.type = GRPC_ARG_STRING;
-  expected_target_arg.key =
-      const_cast<char *>(GRPC_ARG_FAKE_SECURITY_EXPECTED_TARGETS);
 
   char *expected_target_names = NULL;
   const char *backends_name = lb_server->servers_hostport;
   gpr_asprintf(&expected_target_names, "%s;%s", backends_name, BALANCERS_NAME);
 
-  expected_target_arg.value.string = const_cast<char *>(expected_target_names);
+  grpc_fake_resolver_response_generator *response_generator =
+      grpc_fake_resolver_response_generator_create();
+
+  grpc_lb_addresses *addresses = grpc_lb_addresses_create(1, NULL);
+  char *lb_uri_str;
+  gpr_asprintf(&lb_uri_str, "ipv4:%s", lb_server->servers_hostport);
+  grpc_uri *lb_uri = grpc_uri_parse(&exec_ctx, lb_uri_str, true);
+  GPR_ASSERT(lb_uri != NULL);
+  grpc_lb_addresses_set_address_from_uri(addresses, 0, lb_uri, true,
+                                         lb_server->balancer_name, NULL);
+  grpc_uri_destroy(lb_uri);
+  gpr_free(lb_uri_str);
+
+  gpr_asprintf(&cf->server_uri, "test:///%s", lb_server->servers_hostport);
+  const grpc_arg fake_addresses =
+      grpc_lb_addresses_create_channel_arg(addresses);
+  grpc_channel_args *fake_result =
+      grpc_channel_args_copy_and_add(NULL, &fake_addresses, 1);
+  grpc_lb_addresses_destroy(&exec_ctx, addresses);
+
+  const grpc_arg new_args[] = {
+      grpc_fake_transport_expected_targets_arg(expected_target_names),
+      grpc_fake_resolver_response_generator_arg(response_generator)};
+
   grpc_channel_args *args =
-      grpc_channel_args_copy_and_add(NULL, &expected_target_arg, 1);
+      grpc_channel_args_copy_and_add(NULL, new_args, GPR_ARRAY_SIZE(new_args));
   gpr_free(expected_target_names);
 
   cf->cq = grpc_completion_queue_create_for_next(NULL);
-  cf->server_uri = lb_uri;
   grpc_channel_credentials *fake_creds =
       grpc_fake_transport_security_credentials_create();
   cf->client =
       grpc_secure_channel_create(fake_creds, cf->server_uri, args, NULL);
+  grpc_fake_resolver_response_generator_set_response(
+      &exec_ctx, response_generator, fake_result);
+  grpc_channel_args_destroy(&exec_ctx, fake_result);
   grpc_channel_credentials_unref(&exec_ctx, fake_creds);
   grpc_channel_args_destroy(&exec_ctx, args);
+  grpc_fake_resolver_response_generator_unref(response_generator);
+  grpc_exec_ctx_finish(&exec_ctx);
 }
 
 static void teardown_client(client_fixture *cf) {
@@ -787,8 +804,8 @@ TEST(GrpclbTest, InvalidAddressInServerlist) {}
 
 int main(int argc, char **argv) {
   ::testing::InitGoogleTest(&argc, argv);
-  grpc_test_init(argc, argv);
   grpc_fake_resolver_init();
+  grpc_test_init(argc, argv);
   grpc_init();
   const auto result = RUN_ALL_TESTS();
   grpc_shutdown();

test/cpp/interop/client.cc

@@ -163,8 +163,8 @@ int main(int argc, char** argv) {
       std::bind(&grpc::testing::InteropClient::DoUnimplementedMethod, &client);
   actions["unimplemented_service"] =
       std::bind(&grpc::testing::InteropClient::DoUnimplementedService, &client);
-  // actions["cacheable_unary"] =
-  //    std::bind(&grpc::testing::InteropClient::DoCacheableUnary, &client);
+  actions["cacheable_unary"] =
+      std::bind(&grpc::testing::InteropClient::DoCacheableUnary, &client);
 
   UpdateActions(&actions);
 

test/cpp/interop/interop_client.cc

@@ -918,6 +918,26 @@ bool InteropClient::DoCacheableUnary() {
   // second response is a cached copy of the first response
   GPR_ASSERT(response2.payload().body() == response1.payload().body());
 
+  // Request 3
+  // Modify the request body so it will not get a cache hit
+  ts = gpr_now(GPR_CLOCK_PRECISE);
+  timestamp = std::to_string((long long unsigned)ts.tv_nsec);
+  SimpleRequest request1;
+  request1.mutable_payload()->set_body(timestamp.c_str(), timestamp.size());
+  ClientContext context3;
+  SimpleResponse response3;
+  context3.set_cacheable(true);
+  context3.AddMetadata("x-user-ip", "1.2.3.4");
+  Status s3 =
+      serviceStub_.Get()->CacheableUnaryCall(&context3, request1, &response3);
+  if (!AssertStatusOk(s3)) {
+    return false;
+  }
+  gpr_log(GPR_DEBUG, "response 3 payload: %s",
+          response3.payload().body().c_str());
+
+  // Check that the response is different from the previous response.
+  GPR_ASSERT(response3.payload().body() != response1.payload().body());
   return true;
 }
 

test/cpp/microbenchmarks/bm_chttp2_transport.cc

@@ -569,12 +569,17 @@ static void BM_TransportStreamRecv(benchmark::State &state) {
         grpc_closure_sched(exec_ctx, c.get(), GRPC_ERROR_NONE);
         return;
       }
-    } while (grpc_byte_stream_next(exec_ctx, recv_stream, &recv_slice,
+    } while (grpc_byte_stream_next(exec_ctx, recv_stream,
                                    recv_stream->length - received,
-                                   drain_continue.get()));
+                                   drain_continue.get()) &&
+             GRPC_ERROR_NONE ==
+                 grpc_byte_stream_pull(exec_ctx, recv_stream, &recv_slice) &&
+             (received += GRPC_SLICE_LENGTH(recv_slice),
+              grpc_slice_unref_internal(exec_ctx, recv_slice), true));
   });
 
   drain_continue = MakeClosure([&](grpc_exec_ctx *exec_ctx, grpc_error *error) {
+    grpc_byte_stream_pull(exec_ctx, recv_stream, &recv_slice);
     received += GRPC_SLICE_LENGTH(recv_slice);
     grpc_slice_unref_internal(exec_ctx, recv_slice);
     grpc_closure_run(exec_ctx, drain.get(), GRPC_ERROR_NONE);

tools/codegen/core/gen_static_metadata.py

@@ -124,6 +124,7 @@ CONFIG = [
     ('if-unmodified-since', ''),
     ('last-modified', ''),
     ('lb-token', ''),
+    ('lb-cost-bin', ''),
     ('link', ''),
     ('location', ''),
     ('max-forwards', ''),

tools/grift/README.md

@@ -1,6 +1,4 @@
-Copyright 2016 Google Inc.
-
-#Documentation
+# Documentation
 
 grift is integration of [Apache Thrift](https://github.com/apache/thrift.git) Serializer with gRPC.
 
@@ -8,19 +6,19 @@ This integration allows you to use grpc to send thrift messages in C++ and java.
 
 grift uses Compact Protocol to serialize thrift messages. 
 
-##generating grpc plugins for thrift services
+## generating grpc plugins for thrift services
 
-###CPP
+### C++
 ```sh
  $ thrift --gen cpp <thrift-file>
 ```
 
-###JAVA
+### Java
 ```sh
  $ thrift --gen java <thrift-file>
 ```
 
-#Installation
+# Installation
 
 Before Installing thrift make sure to apply this [patch](grpc_plugins_generator.patch) to third_party/thrift.
 Go to third_party/thrift and follow the [INSTALLATION](https://github.com/apache/thrift.git) instructions to install thrift with commit id bcad91771b7f0bff28a1cac1981d7ef2b9bcef3c.

tools/jenkins/run_interop_objc.sh

@@ -0,0 +1,39 @@
+#!/usr/bin/env 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.
+#
+# This script is invoked by Jenkins and runs interop test suite.
+set -ex
+
+export LANG=en_US.UTF-8
+
+# Enter the gRPC repo root
+cd $(dirname $0)/../..
+
+tools/run_tests/run_interop_tests.py -l objc -s all --use_docker -t -j 1 $@ || true

tools/jenkins/run_performance.sh

@@ -32,7 +32,7 @@
 set -ex
 
 # List of benchmarks that provide good signal for analyzing performance changes in pull requests
-BENCHMARKS_TO_RUN="bm_closure bm_cq bm_call_create bm_error bm_chttp2_hpack bm_chttp2_transport bm_pollset bm_metadata"
+BENCHMARKS_TO_RUN="bm_fullstack_unary_ping_pong bm_fullstack_streaming_ping_pong bm_fullstack_streaming_pump bm_closure bm_cq bm_call_create bm_error bm_chttp2_hpack bm_chttp2_transport bm_pollset bm_metadata"
 
 # Enter the gRPC repo root
 cd $(dirname $0)/../..