Merge branch 'merge-parse' of github.com:ctiller/grpc into merge-parse

src/core/ext/client_config/subchannel.c

@@ -219,8 +219,8 @@ static gpr_atm ref_mutate(grpc_subchannel *c, gpr_atm delta,
                             : gpr_atm_no_barrier_fetch_add(&c->ref_pair, delta);
 #ifdef GRPC_STREAM_REFCOUNT_DEBUG
   gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
-          "SUBCHANNEL: %p % 12s 0x%08x -> 0x%08x [%s]", c, purpose, old_val,
-          old_val + delta, reason);
+          "SUBCHANNEL: %p %s 0x%08" PRIxPTR " -> 0x%08" PRIxPTR " [%s]", c,
+          purpose, old_val, old_val + delta, reason);
 #endif
   return old_val;
 }

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

@@ -163,11 +163,9 @@ static void destruct_transport(grpc_exec_ctx *exec_ctx,
     GPR_ASSERT(t->lists[i].tail == NULL);
   }
 
-  GPR_ASSERT(grpc_chttp2_stream_map_size(&t->parsing_stream_map) == 0);
-  GPR_ASSERT(grpc_chttp2_stream_map_size(&t->new_stream_map) == 0);
+  GPR_ASSERT(grpc_chttp2_stream_map_size(&t->stream_map) == 0);
 
-  grpc_chttp2_stream_map_destroy(&t->parsing_stream_map);
-  grpc_chttp2_stream_map_destroy(&t->new_stream_map);
+  grpc_chttp2_stream_map_destroy(&t->stream_map);
   grpc_connectivity_state_destroy(exec_ctx, &t->channel_callback.state_tracker);
 
   grpc_combiner_destroy(exec_ctx, t->executor.combiner);
@@ -277,8 +275,7 @@ static void init_transport(grpc_exec_ctx *exec_ctx, grpc_chttp2_transport *t,
      large enough that the exponential growth should happen nicely when it's
      needed.
      TODO(ctiller): tune this */
-  grpc_chttp2_stream_map_init(&t->parsing_stream_map, 8);
-  grpc_chttp2_stream_map_init(&t->new_stream_map, 8);
+  grpc_chttp2_stream_map_init(&t->stream_map, 8);
 
   /* copy in initial settings to all setting sets */
   for (i = 0; i < GRPC_CHTTP2_NUM_SETTINGS; i++) {
@@ -501,7 +498,6 @@ static int init_stream(grpc_exec_ctx *exec_ctx, grpc_transport *gt,
   REF_TRANSPORT(t, "stream");
 
   if (server_data) {
-    GPR_ASSERT(t->executor.parsing_active);
     s->global.id = (uint32_t)(uintptr_t)server_data;
     s->global.outgoing_window =
         t->global.settings[GRPC_PEER_SETTINGS]
@@ -510,15 +506,16 @@ static int init_stream(grpc_exec_ctx *exec_ctx, grpc_transport *gt,
         t->global.settings[GRPC_SENT_SETTINGS]
                           [GRPC_CHTTP2_SETTINGS_INITIAL_WINDOW_SIZE];
     *t->accepting_stream = s;
-    grpc_chttp2_stream_map_add(&t->parsing_stream_map, s->global.id, s);
+    grpc_chttp2_stream_map_add(&t->stream_map, s->global.id, s);
+    grpc_chttp2_register_stream(t, s);
     s->global.in_stream_map = true;
+  } else {
+    grpc_closure_init(&s->init_stream, finish_init_stream_locked, s);
+    GRPC_CHTTP2_STREAM_REF(&s->global, "init");
+    grpc_combiner_execute(exec_ctx, t->executor.combiner, &s->init_stream,
+                          GRPC_ERROR_NONE);
   }
 
-  grpc_closure_init(&s->init_stream, finish_init_stream_locked, s);
-  GRPC_CHTTP2_STREAM_REF(&s->global, "init");
-  grpc_combiner_execute(exec_ctx, t->executor.combiner, &s->init_stream,
-                        GRPC_ERROR_NONE);
-
   GPR_TIMER_END("init_stream", 0);
 
   return 0;
@@ -540,9 +537,9 @@ static void destroy_stream_locked(grpc_exec_ctx *exec_ctx, void *sp,
         exec_ctx, t,
         GRPC_ERROR_CREATE("Last stream closed after sending goaway"));
   }
-  if (!t->executor.parsing_active && s->global.id) {
-    GPR_ASSERT(grpc_chttp2_stream_map_find(&t->parsing_stream_map,
-                                           s->global.id) == NULL);
+  if (s->global.id != 0) {
+    GPR_ASSERT(grpc_chttp2_stream_map_find(&t->stream_map, s->global.id) ==
+               NULL);
   }
 
   while (
@@ -597,8 +594,7 @@ static void destroy_stream(grpc_exec_ctx *exec_ctx, grpc_transport *gt,
 grpc_chttp2_stream_global *grpc_chttp2_parsing_lookup_stream(
     grpc_chttp2_transport_global *transport_global, uint32_t id) {
   grpc_chttp2_transport *t = TRANSPORT_FROM_GLOBAL(transport_global);
-  grpc_chttp2_stream *s =
-      grpc_chttp2_stream_map_find(&t->parsing_stream_map, id);
+  grpc_chttp2_stream *s = grpc_chttp2_stream_map_find(&t->stream_map, id);
   return s ? &s->global : NULL;
 }
 
@@ -879,7 +875,8 @@ static void maybe_start_some_streams(
   /* start streams where we have free grpc_chttp2_stream ids and free
    * concurrency */
   while (transport_global->next_stream_id <= MAX_CLIENT_STREAM_ID &&
-         transport_global->concurrent_stream_count <
+         grpc_chttp2_stream_map_size(
+             &TRANSPORT_FROM_GLOBAL(transport_global)->stream_map) <
              transport_global
                  ->settings[GRPC_PEER_SETTINGS]
                            [GRPC_CHTTP2_SETTINGS_MAX_CONCURRENT_STREAMS] &&
@@ -910,10 +907,9 @@ static void maybe_start_some_streams(
     stream_global->max_recv_bytes =
         GPR_MAX(stream_incoming_window, stream_global->max_recv_bytes);
     grpc_chttp2_stream_map_add(
-        &TRANSPORT_FROM_GLOBAL(transport_global)->new_stream_map,
-        stream_global->id, STREAM_FROM_GLOBAL(stream_global));
+        &TRANSPORT_FROM_GLOBAL(transport_global)->stream_map, stream_global->id,
+        STREAM_FROM_GLOBAL(stream_global));
     stream_global->in_stream_map = true;
-    transport_global->concurrent_stream_count++;
     grpc_chttp2_become_writable(exec_ctx, transport_global, stream_global, true,
                                 "new_stream");
   }
@@ -1246,15 +1242,6 @@ static void perform_transport_op_locked(grpc_exec_ctx *exec_ctx,
   grpc_chttp2_transport *t = op->transport_private.args[0];
   grpc_error *close_transport = op->disconnect_with_error;
 
-  /* If there's a set_accept_stream ensure that we're not parsing
-     to avoid changing things out from underneath */
-  if (t->executor.parsing_active && op->set_accept_stream) {
-    GPR_ASSERT(t->post_parsing_op == NULL);
-    t->post_parsing_op = gpr_malloc(sizeof(*op));
-    memcpy(t->post_parsing_op, op, sizeof(*op));
-    return;
-  }
-
   if (op->on_connectivity_state_change != NULL) {
     grpc_connectivity_state_notify_on_state_change(
         exec_ctx, &t->channel_callback.state_tracker, op->connectivity_state,
@@ -1407,12 +1394,7 @@ static void decrement_active_streams_locked(
 
 static void remove_stream(grpc_exec_ctx *exec_ctx, grpc_chttp2_transport *t,
                           uint32_t id, grpc_error *error) {
-  size_t new_stream_count;
-  grpc_chttp2_stream *s =
-      grpc_chttp2_stream_map_delete(&t->parsing_stream_map, id);
-  if (!s) {
-    s = grpc_chttp2_stream_map_delete(&t->new_stream_map, id);
-  }
+  grpc_chttp2_stream *s = grpc_chttp2_stream_map_delete(&t->stream_map, id);
   GPR_ASSERT(s);
   s->global.in_stream_map = false;
   if (t->global.incoming_stream == &s->global) {
@@ -1435,14 +1417,9 @@ static void remove_stream(grpc_exec_ctx *exec_ctx, grpc_chttp2_transport *t,
     GRPC_CHTTP2_STREAM_UNREF(exec_ctx, &s->global, "chttp2_writing");
   }
 
-  new_stream_count = grpc_chttp2_stream_map_size(&t->parsing_stream_map) +
-                     grpc_chttp2_stream_map_size(&t->new_stream_map);
-  GPR_ASSERT(new_stream_count <= UINT32_MAX);
-  if (new_stream_count != t->global.concurrent_stream_count) {
-    t->global.concurrent_stream_count = (uint32_t)new_stream_count;
-    maybe_start_some_streams(exec_ctx, &t->global);
-  }
   GRPC_ERROR_UNREF(error);
+
+  maybe_start_some_streams(exec_ctx, &t->global);
 }
 
 static void status_codes_from_error(grpc_error *error, gpr_timespec deadline,
@@ -1627,18 +1604,12 @@ void grpc_chttp2_mark_stream_closed(
     }
   }
   if (stream_global->read_closed && stream_global->write_closed) {
-    if (stream_global->id != 0 &&
-        TRANSPORT_FROM_GLOBAL(transport_global)->executor.parsing_active) {
-      grpc_chttp2_list_add_closed_waiting_for_parsing(transport_global,
-                                                      stream_global);
-    } else {
-      if (stream_global->id != 0) {
-        remove_stream(exec_ctx, TRANSPORT_FROM_GLOBAL(transport_global),
-                      stream_global->id,
-                      removal_error(GRPC_ERROR_REF(error), stream_global));
-      }
-      GRPC_CHTTP2_STREAM_UNREF(exec_ctx, stream_global, "chttp2");
+    if (stream_global->id != 0) {
+      remove_stream(exec_ctx, TRANSPORT_FROM_GLOBAL(transport_global),
+                    stream_global->id,
+                    removal_error(GRPC_ERROR_REF(error), stream_global));
     }
+    GRPC_CHTTP2_STREAM_UNREF(exec_ctx, stream_global, "chttp2");
   }
   GRPC_ERROR_UNREF(error);
 }
@@ -1874,13 +1845,7 @@ static void reading_action_locked(grpc_exec_ctx *exec_ctx, void *tp,
 
   GRPC_ERROR_REF(error);
 
-  GPR_ASSERT(!t->executor.parsing_active);
   if (!t->closed) {
-    t->executor.parsing_active = 1;
-    /* merge stream lists */
-    grpc_chttp2_stream_map_move_into(&t->new_stream_map,
-                                     &t->parsing_stream_map);
-
     GPR_TIMER_BEGIN("reading_action.parse", 0);
     size_t i = 0;
     grpc_error *errors[3] = {GRPC_ERROR_REF(error), GRPC_ERROR_NONE,
@@ -1903,8 +1868,8 @@ static void reading_action_locked(grpc_exec_ctx *exec_ctx, void *tp,
     GPR_TIMER_BEGIN("post_parse_locked", 0);
     if (transport_global->initial_window_update != 0) {
       update_global_window_args args = {t, exec_ctx};
-      grpc_chttp2_stream_map_for_each(&t->parsing_stream_map,
-                                      update_global_window, &args);
+      grpc_chttp2_stream_map_for_each(&t->stream_map, update_global_window,
+                                      &args);
       transport_global->initial_window_update = 0;
     }
     /* handle higher level things */
@@ -1919,27 +1884,6 @@ static void reading_action_locked(grpc_exec_ctx *exec_ctx, void *tp,
       grpc_chttp2_initiate_write(exec_ctx, transport_global, false,
                                  "global incoming window");
     }
-    t->executor.parsing_active = 0;
-    /* handle delayed transport ops (if there is one) */
-    if (t->post_parsing_op) {
-      grpc_transport_op *op = t->post_parsing_op;
-      t->post_parsing_op = NULL;
-      perform_transport_op_locked(exec_ctx, op, GRPC_ERROR_NONE);
-      gpr_free(op);
-    }
-    /* if a stream is in the stream map, and gets cancelled, we need to
-     * ensure we are not parsing before continuing the cancellation to keep
-     * things in a sane state */
-    grpc_chttp2_stream_global *stream_global;
-    while (grpc_chttp2_list_pop_closed_waiting_for_parsing(transport_global,
-                                                           &stream_global)) {
-      GPR_ASSERT(stream_global->in_stream_map);
-      GPR_ASSERT(stream_global->write_closed);
-      GPR_ASSERT(stream_global->read_closed);
-      remove_stream(exec_ctx, t, stream_global->id,
-                    removal_error(GRPC_ERROR_NONE, stream_global));
-      GRPC_CHTTP2_STREAM_UNREF(exec_ctx, stream_global, "chttp2");
-    }
 
     GPR_TIMER_END("post_parse_locked", 0);
   }

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

@@ -64,7 +64,6 @@ typedef enum {
   GRPC_CHTTP2_LIST_WRITABLE,
   GRPC_CHTTP2_LIST_WRITING,
   GRPC_CHTTP2_LIST_WRITTEN,
-  GRPC_CHTTP2_LIST_CLOSED_WAITING_FOR_PARSING,
   GRPC_CHTTP2_LIST_CLOSED_WAITING_FOR_WRITING,
   GRPC_CHTTP2_LIST_STALLED_BY_TRANSPORT,
   /* streams waiting for the outgoing window in the writing path, they will be
@@ -218,10 +217,6 @@ struct grpc_chttp2_transport_global {
   /** next payload for an outgoing ping */
   uint64_t ping_counter;
 
-  /** concurrent stream count: updated when not parsing,
-      so this is a strict over-estimation on the client */
-  uint32_t concurrent_stream_count;
-
   /** parser for headers */
   grpc_chttp2_hpack_parser hpack_parser;
   /** simple one shot parsers */
@@ -308,10 +303,6 @@ struct grpc_chttp2_transport {
   struct {
     grpc_combiner *combiner;
 
-    /** is a thread currently in the global lock */
-    bool global_active;
-    /** is a thread currently parsing */
-    bool parsing_active;
     /** write execution state of the transport */
     grpc_chttp2_write_state write_state;
     /** has a check_read_ops been scheduled */
@@ -336,14 +327,8 @@ struct grpc_chttp2_transport {
       chain. */
   grpc_chttp2_transport_writing writing;
 
-  /** maps stream id to grpc_chttp2_stream objects;
-      owned by the parsing thread when parsing */
-  grpc_chttp2_stream_map parsing_stream_map;
-
-  /** streams created by the client (possibly during parsing);
-      merged with parsing_stream_map during unlock when no
-      parsing is occurring */
-  grpc_chttp2_stream_map new_stream_map;
+  /** maps stream id to grpc_chttp2_stream objects */
+  grpc_chttp2_stream_map stream_map;
 
   /** closure to execute writing */
   grpc_closure writing_action;
@@ -374,9 +359,6 @@ struct grpc_chttp2_transport {
     /** connectivity tracking */
     grpc_connectivity_state_tracker state_tracker;
   } channel_callback;
-
-  /** Transport op to be applied post-parsing */
-  grpc_transport_op *post_parsing_op;
 };
 
 struct grpc_chttp2_stream_global {
@@ -602,13 +584,6 @@ void grpc_chttp2_list_remove_stalled_by_transport(
     grpc_chttp2_transport_global *transport_global,
     grpc_chttp2_stream_global *stream_global);
 
-void grpc_chttp2_list_add_closed_waiting_for_parsing(
-    grpc_chttp2_transport_global *transport_global,
-    grpc_chttp2_stream_global *stream_global);
-int grpc_chttp2_list_pop_closed_waiting_for_parsing(
-    grpc_chttp2_transport_global *transport_global,
-    grpc_chttp2_stream_global **stream_global);
-
 void grpc_chttp2_list_add_closed_waiting_for_writing(
     grpc_chttp2_transport_global *transport_global,
     grpc_chttp2_stream_global *stream_global);

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

@@ -334,26 +334,6 @@ void grpc_chttp2_list_remove_stalled_by_transport(
                            GRPC_CHTTP2_LIST_STALLED_BY_TRANSPORT);
 }
 
-void grpc_chttp2_list_add_closed_waiting_for_parsing(
-    grpc_chttp2_transport_global *transport_global,
-    grpc_chttp2_stream_global *stream_global) {
-  stream_list_add(TRANSPORT_FROM_GLOBAL(transport_global),
-                  STREAM_FROM_GLOBAL(stream_global),
-                  GRPC_CHTTP2_LIST_CLOSED_WAITING_FOR_PARSING);
-}
-
-int grpc_chttp2_list_pop_closed_waiting_for_parsing(
-    grpc_chttp2_transport_global *transport_global,
-    grpc_chttp2_stream_global **stream_global) {
-  grpc_chttp2_stream *stream;
-  int r = stream_list_pop(TRANSPORT_FROM_GLOBAL(transport_global), &stream,
-                          GRPC_CHTTP2_LIST_CLOSED_WAITING_FOR_PARSING);
-  if (r != 0) {
-    *stream_global = &stream->global;
-  }
-  return r;
-}
-
 void grpc_chttp2_list_add_closed_waiting_for_writing(
     grpc_chttp2_transport_global *transport_global,
     grpc_chttp2_stream_global *stream_global) {

src/core/lib/iomgr/error.c

@@ -265,7 +265,7 @@ static grpc_error *copy_error_and_unref(grpc_error *in) {
   } else {
     out = gpr_malloc(sizeof(*out));
 #ifdef GRPC_ERROR_REFCOUNT_DEBUG
-    gpr_log(GPR_DEBUG, "%p create copying", out);
+    gpr_log(GPR_DEBUG, "%p create copying %p", out, in);
 #endif
     out->ints = gpr_avl_ref(in->ints);
     out->strs = gpr_avl_ref(in->strs);

src/core/lib/surface/call.c

@@ -230,33 +230,33 @@ static void destroy_call(grpc_exec_ctx *exec_ctx, void *call_stack,
 static void receiving_slice_ready(grpc_exec_ctx *exec_ctx, void *bctlp,
                                   grpc_error *error);
 
-grpc_call *grpc_call_create(
-    grpc_channel *channel, grpc_call *parent_call, uint32_t propagation_mask,
-    grpc_completion_queue *cq, grpc_pollset_set *pollset_set_alternative,
-    const void *server_transport_data, grpc_mdelem **add_initial_metadata,
-    size_t add_initial_metadata_count, gpr_timespec send_deadline) {
+grpc_error *grpc_call_create(const grpc_call_create_args *args,
+                             grpc_call **out_call) {
   size_t i, j;
-  grpc_channel_stack *channel_stack = grpc_channel_get_channel_stack(channel);
+  grpc_channel_stack *channel_stack =
+      grpc_channel_get_channel_stack(args->channel);
   grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
   grpc_call *call;
   GPR_TIMER_BEGIN("grpc_call_create", 0);
-  call = gpr_malloc(sizeof(grpc_call) + channel_stack->call_stack_size);
+  *out_call = call =
+      gpr_malloc(sizeof(grpc_call) + channel_stack->call_stack_size);
   memset(call, 0, sizeof(grpc_call));
   gpr_mu_init(&call->mu);
-  call->channel = channel;
-  call->cq = cq;
-  call->parent = parent_call;
+  call->channel = args->channel;
+  call->cq = args->cq;
+  call->parent = args->parent_call;
   /* Always support no compression */
   GPR_BITSET(&call->encodings_accepted_by_peer, GRPC_COMPRESS_NONE);
-  call->is_client = server_transport_data == NULL;
+  call->is_client = args->server_transport_data == NULL;
   if (call->is_client) {
-    GPR_ASSERT(add_initial_metadata_count < MAX_SEND_EXTRA_METADATA_COUNT);
-    for (i = 0; i < add_initial_metadata_count; i++) {
-      call->send_extra_metadata[i].md = add_initial_metadata[i];
+    GPR_ASSERT(args->add_initial_metadata_count <
+               MAX_SEND_EXTRA_METADATA_COUNT);
+    for (i = 0; i < args->add_initial_metadata_count; i++) {
+      call->send_extra_metadata[i].md = args->add_initial_metadata[i];
     }
-    call->send_extra_metadata_count = (int)add_initial_metadata_count;
+    call->send_extra_metadata_count = (int)args->add_initial_metadata_count;
   } else {
-    GPR_ASSERT(add_initial_metadata_count == 0);
+    GPR_ASSERT(args->add_initial_metadata_count == 0);
     call->send_extra_metadata_count = 0;
   }
   for (i = 0; i < 2; i++) {
@@ -265,78 +265,79 @@ grpc_call *grpc_call_create(
     }
   }
   call->send_deadline =
-      gpr_convert_clock_type(send_deadline, GPR_CLOCK_MONOTONIC);
-  GRPC_CHANNEL_INTERNAL_REF(channel, "call");
+      gpr_convert_clock_type(args->send_deadline, GPR_CLOCK_MONOTONIC);
+  GRPC_CHANNEL_INTERNAL_REF(args->channel, "call");
   /* initial refcount dropped by grpc_call_destroy */
   grpc_error *error = grpc_call_stack_init(
       &exec_ctx, channel_stack, 1, destroy_call, call, call->context,
-      server_transport_data, CALL_STACK_FROM_CALL(call));
+      args->server_transport_data, CALL_STACK_FROM_CALL(call));
   if (error != GRPC_ERROR_NONE) {
     intptr_t status;
-    if (!grpc_error_get_int(error, GRPC_ERROR_INT_GRPC_STATUS, &status))
+    if (!grpc_error_get_int(error, GRPC_ERROR_INT_GRPC_STATUS, &status)) {
       status = GRPC_STATUS_UNKNOWN;
+    }
     const char *error_str =
         grpc_error_get_str(error, GRPC_ERROR_STR_DESCRIPTION);
     close_with_status(&exec_ctx, call, (grpc_status_code)status,
                       error_str == NULL ? "unknown error" : error_str);
-    GRPC_ERROR_UNREF(error);
   }
-  if (cq != NULL) {
+  if (args->cq != NULL) {
     GPR_ASSERT(
-        pollset_set_alternative == NULL &&
+        args->pollset_set_alternative == NULL &&
         "Only one of 'cq' and 'pollset_set_alternative' should be non-NULL.");
-    GRPC_CQ_INTERNAL_REF(cq, "bind");
+    GRPC_CQ_INTERNAL_REF(args->cq, "bind");
     call->pollent =
-        grpc_polling_entity_create_from_pollset(grpc_cq_pollset(cq));
+        grpc_polling_entity_create_from_pollset(grpc_cq_pollset(args->cq));
   }
-  if (pollset_set_alternative != NULL) {
-    call->pollent =
-        grpc_polling_entity_create_from_pollset_set(pollset_set_alternative);
+  if (args->pollset_set_alternative != NULL) {
+    call->pollent = grpc_polling_entity_create_from_pollset_set(
+        args->pollset_set_alternative);
   }
   if (!grpc_polling_entity_is_empty(&call->pollent)) {
     grpc_call_stack_set_pollset_or_pollset_set(
         &exec_ctx, CALL_STACK_FROM_CALL(call), &call->pollent);
   }
-  if (parent_call != NULL) {
-    GRPC_CALL_INTERNAL_REF(parent_call, "child");
+  gpr_timespec send_deadline = args->send_deadline;
+  if (args->parent_call != NULL) {
+    GRPC_CALL_INTERNAL_REF(args->parent_call, "child");
     GPR_ASSERT(call->is_client);
-    GPR_ASSERT(!parent_call->is_client);
+    GPR_ASSERT(!args->parent_call->is_client);
 
-    gpr_mu_lock(&parent_call->mu);
+    gpr_mu_lock(&args->parent_call->mu);
 
-    if (propagation_mask & GRPC_PROPAGATE_DEADLINE) {
+    if (args->propagation_mask & GRPC_PROPAGATE_DEADLINE) {
       send_deadline = gpr_time_min(
           gpr_convert_clock_type(send_deadline,
-                                 parent_call->send_deadline.clock_type),
-          parent_call->send_deadline);
+                                 args->parent_call->send_deadline.clock_type),
+          args->parent_call->send_deadline);
     }
     /* for now GRPC_PROPAGATE_TRACING_CONTEXT *MUST* be passed with
      * GRPC_PROPAGATE_STATS_CONTEXT */
     /* TODO(ctiller): This should change to use the appropriate census start_op
      * call. */
-    if (propagation_mask & GRPC_PROPAGATE_CENSUS_TRACING_CONTEXT) {
-      GPR_ASSERT(propagation_mask & GRPC_PROPAGATE_CENSUS_STATS_CONTEXT);
-      grpc_call_context_set(call, GRPC_CONTEXT_TRACING,
-                            parent_call->context[GRPC_CONTEXT_TRACING].value,
-                            NULL);
+    if (args->propagation_mask & GRPC_PROPAGATE_CENSUS_TRACING_CONTEXT) {
+      GPR_ASSERT(args->propagation_mask & GRPC_PROPAGATE_CENSUS_STATS_CONTEXT);
+      grpc_call_context_set(
+          call, GRPC_CONTEXT_TRACING,
+          args->parent_call->context[GRPC_CONTEXT_TRACING].value, NULL);
     } else {
-      GPR_ASSERT(propagation_mask & GRPC_PROPAGATE_CENSUS_STATS_CONTEXT);
+      GPR_ASSERT(args->propagation_mask & GRPC_PROPAGATE_CENSUS_STATS_CONTEXT);
     }
-    if (propagation_mask & GRPC_PROPAGATE_CANCELLATION) {
+    if (args->propagation_mask & GRPC_PROPAGATE_CANCELLATION) {
       call->cancellation_is_inherited = 1;
     }
 
-    if (parent_call->first_child == NULL) {
-      parent_call->first_child = call;
+    if (args->parent_call->first_child == NULL) {
+      args->parent_call->first_child = call;
       call->sibling_next = call->sibling_prev = call;
     } else {
-      call->sibling_next = parent_call->first_child;
-      call->sibling_prev = parent_call->first_child->sibling_prev;
+      call->sibling_next = args->parent_call->first_child;
+      call->sibling_prev = args->parent_call->first_child->sibling_prev;
       call->sibling_next->sibling_prev = call->sibling_prev->sibling_next =
           call;
     }
 
-    gpr_mu_unlock(&parent_call->mu);
+    gpr_mu_unlock(&args->parent_call->mu);
   }
   if (gpr_time_cmp(send_deadline, gpr_inf_future(send_deadline.clock_type)) !=
       0) {
@@ -344,7 +345,7 @@ grpc_call *grpc_call_create(
   }
   grpc_exec_ctx_finish(&exec_ctx);
   GPR_TIMER_END("grpc_call_create", 0);
-  return call;
+  return error;
 }
 
 void grpc_call_set_completion_queue(grpc_exec_ctx *exec_ctx, grpc_call *call,

src/core/lib/surface/call.h

@@ -49,15 +49,29 @@ typedef void (*grpc_ioreq_completion_func)(grpc_exec_ctx *exec_ctx,
                                            grpc_call *call, int success,
                                            void *user_data);
 
-grpc_call *grpc_call_create(grpc_channel *channel, grpc_call *parent_call,
-                            uint32_t propagation_mask,
-                            grpc_completion_queue *cq,
-                            /* if not NULL, it'll be used in lieu of \a cq */
-                            grpc_pollset_set *pollset_set_alternative,
-                            const void *server_transport_data,
-                            grpc_mdelem **add_initial_metadata,
-                            size_t add_initial_metadata_count,
-                            gpr_timespec send_deadline);
+typedef struct grpc_call_create_args {
+  grpc_channel *channel;
+
+  grpc_call *parent_call;
+  uint32_t propagation_mask;
+
+  grpc_completion_queue *cq;
+  /* if not NULL, it'll be used in lieu of cq */
+  grpc_pollset_set *pollset_set_alternative;
+
+  const void *server_transport_data;
+
+  grpc_mdelem **add_initial_metadata;
+  size_t add_initial_metadata_count;
+
+  gpr_timespec send_deadline;
+} grpc_call_create_args;
+
+/* Create a new call based on \a args.
+   Regardless of success or failure, always returns a valid new call into *call
+   */
+grpc_error *grpc_call_create(const grpc_call_create_args *args,
+                             grpc_call **call);
 
 void grpc_call_set_completion_queue(grpc_exec_ctx *exec_ctx, grpc_call *call,
                                     grpc_completion_queue *cq);

src/core/lib/surface/channel.c

@@ -208,9 +208,21 @@ static grpc_call *grpc_channel_create_call_internal(
     send_metadata[num_metadata++] = GRPC_MDELEM_REF(channel->default_authority);
   }
 
-  return grpc_call_create(channel, parent_call, propagation_mask, cq,
-                          pollset_set_alternative, NULL, send_metadata,
-                          num_metadata, deadline);
+  grpc_call_create_args args;
+  memset(&args, 0, sizeof(args));
+  args.channel = channel;
+  args.parent_call = parent_call;
+  args.propagation_mask = propagation_mask;
+  args.cq = cq;
+  args.pollset_set_alternative = pollset_set_alternative;
+  args.server_transport_data = NULL;
+  args.add_initial_metadata = send_metadata;
+  args.add_initial_metadata_count = num_metadata;
+  args.send_deadline = deadline;
+
+  grpc_call *call;
+  GRPC_LOG_IF_ERROR("call_create", grpc_call_create(&args, &call));
+  return call;
 }
 
 grpc_call *grpc_channel_create_call(grpc_channel *channel,

src/core/lib/surface/server.c

@@ -824,11 +824,20 @@ static void accept_stream(grpc_exec_ctx *exec_ctx, void *cd,
                           const void *transport_server_data) {
   channel_data *chand = cd;
   /* create a call */
-  grpc_call *call = grpc_call_create(chand->channel, NULL, 0, NULL, NULL,
-                                     transport_server_data, NULL, 0,
-                                     gpr_inf_future(GPR_CLOCK_MONOTONIC));
+  grpc_call_create_args args;
+  memset(&args, 0, sizeof(args));
+  args.channel = chand->channel;
+  args.server_transport_data = transport_server_data;
+  args.send_deadline = gpr_inf_future(GPR_CLOCK_MONOTONIC);
+  grpc_call *call;
+  grpc_error *error = grpc_call_create(&args, &call);
   grpc_call_element *elem =
       grpc_call_stack_element(grpc_call_get_call_stack(call), 0);
+  if (error != GRPC_ERROR_NONE) {
+    got_initial_metadata(exec_ctx, elem, error);
+    GRPC_ERROR_UNREF(error);
+    return;
+  }
   call_data *calld = elem->call_data;
   grpc_op op;
   memset(&op, 0, sizeof(op));

src/core/lib/transport/transport.c

@@ -46,8 +46,9 @@
 #ifdef GRPC_STREAM_REFCOUNT_DEBUG
 void grpc_stream_ref(grpc_stream_refcount *refcount, const char *reason) {
   gpr_atm val = gpr_atm_no_barrier_load(&refcount->refs.count);
-  gpr_log(GPR_DEBUG, "%s %p:%p   REF %d->%d %s", refcount->object_type,
-          refcount, refcount->destroy.cb_arg, val, val + 1, reason);
+  gpr_log(GPR_DEBUG, "%s %p:%p   REF %" PRIdPTR "->%" PRIdPTR " %s",
+          refcount->object_type, refcount, refcount->destroy.cb_arg, val,
+          val + 1, reason);
 #else
 void grpc_stream_ref(grpc_stream_refcount *refcount) {
 #endif
@@ -58,8 +59,9 @@ void grpc_stream_ref(grpc_stream_refcount *refcount) {
 void grpc_stream_unref(grpc_exec_ctx *exec_ctx, grpc_stream_refcount *refcount,
                        const char *reason) {
   gpr_atm val = gpr_atm_no_barrier_load(&refcount->refs.count);
-  gpr_log(GPR_DEBUG, "%s %p:%p UNREF %d->%d %s", refcount->object_type,
-          refcount, refcount->destroy.cb_arg, val, val - 1, reason);
+  gpr_log(GPR_DEBUG, "%s %p:%p UNREF %" PRIdPTR "->%" PRIdPTR " %s",
+          refcount->object_type, refcount, refcount->destroy.cb_arg, val,
+          val - 1, reason);
 #else
 void grpc_stream_unref(grpc_exec_ctx *exec_ctx,
                        grpc_stream_refcount *refcount) {

src/core/lib/transport/transport.h

@@ -55,7 +55,7 @@ typedef struct grpc_transport grpc_transport;
    for a stream. */
 typedef struct grpc_stream grpc_stream;
 
-//#define GRPC_STREAM_REFCOUNT_DEBUG
+#define GRPC_STREAM_REFCOUNT_DEBUG
 
 typedef struct grpc_stream_refcount {
   gpr_refcount refs;