Fixes

src/core/ext/client_config/subchannel_call_holder.c

@@ -207,6 +207,10 @@ typedef struct {
 
 static void retry_waiting_locked(grpc_exec_ctx *exec_ctx,
                                  grpc_subchannel_call_holder *holder) {
+  if (holder->waiting_ops_count == 0) {
+    return;
+  }
+
   retry_ops_args *a = gpr_malloc(sizeof(*a));
   a->ops = holder->waiting_ops;
   a->nops = holder->waiting_ops_count;

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

@@ -311,7 +311,7 @@ static void init_transport(grpc_exec_ctx *exec_ctx, grpc_chttp2_transport *t,
 
   if (is_client) {
     gpr_slice_buffer_add(
-        &t->global.qbuf,
+        &t->writing.outbuf,
         gpr_slice_from_copied_string(GRPC_CHTTP2_CLIENT_CONNECT_STRING));
     grpc_chttp2_initiate_write(exec_ctx, &t->global, false, "initial_write");
   }
@@ -768,7 +768,7 @@ static void start_writing(grpc_exec_ctx *exec_ctx, grpc_chttp2_transport *t) {
       set_write_state(t, GRPC_CHTTP2_WRITING_INACTIVE,
                       "start_writing:nothing_to_write");
     }
-    end_waiting_for_write(exec_ctx, t, GRPC_ERROR_CREATE("Nothing to write"));
+    end_waiting_for_write(exec_ctx, t, GRPC_ERROR_NONE);
     UNREF_TRANSPORT(exec_ctx, t, "writing");
   }
   GPR_TIMER_END("start_writing", 0);

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

@@ -51,15 +51,6 @@ int grpc_chttp2_unlocking_check_writes(
 
   GPR_TIMER_BEGIN("grpc_chttp2_unlocking_check_writes", 0);
 
-  /* simple writes are queued to qbuf, and flushed here */
-  gpr_slice_buffer_swap(&transport_global->qbuf, &transport_writing->outbuf);
-  GPR_ASSERT(transport_global->qbuf.count == 0);
-
-  grpc_chttp2_hpack_compressor_set_max_table_size(
-      &transport_writing->hpack_compressor,
-      transport_global->settings[GRPC_PEER_SETTINGS]
-                                [GRPC_CHTTP2_SETTINGS_HEADER_TABLE_SIZE]);
-
   if (transport_global->dirtied_local_settings &&
       !transport_global->sent_local_settings) {
     gpr_slice_buffer_add(
@@ -73,6 +64,16 @@ int grpc_chttp2_unlocking_check_writes(
     transport_global->sent_local_settings = 1;
   }
 
+  /* simple writes are queued to qbuf, and flushed here */
+  gpr_slice_buffer_move_into(&transport_global->qbuf,
+                             &transport_writing->outbuf);
+  GPR_ASSERT(transport_global->qbuf.count == 0);
+
+  grpc_chttp2_hpack_compressor_set_max_table_size(
+      &transport_writing->hpack_compressor,
+      transport_global->settings[GRPC_PEER_SETTINGS]
+                                [GRPC_CHTTP2_SETTINGS_HEADER_TABLE_SIZE]);
+
   GRPC_CHTTP2_FLOW_MOVE_TRANSPORT("write", transport_writing, outgoing_window,
                                   transport_global, outgoing_window);
   if (transport_writing->outgoing_window > 0) {

src/core/lib/iomgr/ev_epoll_linux.c

@@ -1526,6 +1526,8 @@ static grpc_error *pollset_work(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
 
 static void pollset_add_fd(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
                            grpc_fd *fd) {
+  GPR_TIMER_BEGIN("pollset_add_fd", 0);
+
   grpc_error *error = GRPC_ERROR_NONE;
 
   gpr_mu_lock(&pollset->mu);
@@ -1638,6 +1640,8 @@ retry:
   gpr_mu_unlock(&pollset->mu);
 
   GRPC_LOG_IF_ERROR("pollset_add_fd", error);
+
+  GPR_TIMER_END("pollset_add_fd", 0);
 }
 
 /*******************************************************************************

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

@@ -40,6 +40,7 @@
 #include <grpc/support/string_util.h>
 
 #include "src/core/lib/channel/channel_stack.h"
+#include "src/core/lib/profiling/timers.h"
 #include "src/core/lib/security/context/security_context.h"
 #include "src/core/lib/security/credentials/credentials.h"
 #include "src/core/lib/security/transport/security_connector.h"
@@ -218,6 +219,8 @@ static void on_host_checked(grpc_exec_ctx *exec_ctx, void *user_data,
 static void auth_start_transport_op(grpc_exec_ctx *exec_ctx,
                                     grpc_call_element *elem,
                                     grpc_transport_stream_op *op) {
+  GPR_TIMER_BEGIN("auth_start_transport_op", 0);
+
   /* grab pointers to our data from the call element */
   call_data *calld = elem->call_data;
   channel_data *chand = elem->channel_data;
@@ -258,12 +261,14 @@ static void auth_start_transport_op(grpc_exec_ctx *exec_ctx,
       grpc_channel_security_connector_check_call_host(
           exec_ctx, chand->security_connector, call_host, chand->auth_context,
           on_host_checked, elem);
+      GPR_TIMER_END("auth_start_transport_op", 0);
       return; /* early exit */
     }
   }
 
   /* pass control down the stack */
   grpc_call_next_op(exec_ctx, elem, op);
+  GPR_TIMER_END("auth_start_transport_op", 0);
 }
 
 /* Constructor for call_data */

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

@@ -38,6 +38,7 @@
 #include <grpc/support/slice_buffer.h>
 #include <grpc/support/sync.h>
 #include "src/core/lib/debug/trace.h"
+#include "src/core/lib/profiling/timers.h"
 #include "src/core/lib/security/transport/tsi_error.h"
 #include "src/core/lib/support/string.h"
 #include "src/core/lib/tsi/transport_security_interface.h"
@@ -248,6 +249,8 @@ static void flush_write_staging_buffer(secure_endpoint *ep, uint8_t **cur,
 
 static void endpoint_write(grpc_exec_ctx *exec_ctx, grpc_endpoint *secure_ep,
                            gpr_slice_buffer *slices, grpc_closure *cb) {
+  GPR_TIMER_BEGIN("secure_endpoint.endpoint_write", 0);
+
   unsigned i;
   tsi_result result = TSI_OK;
   secure_endpoint *ep = (secure_endpoint *)secure_ep;
@@ -323,10 +326,12 @@ static void endpoint_write(grpc_exec_ctx *exec_ctx, grpc_endpoint *secure_ep,
         exec_ctx, cb,
         grpc_set_tsi_error_result(GRPC_ERROR_CREATE("Wrap failed"), result),
         NULL);
+    GPR_TIMER_END("secure_endpoint.endpoint_write", 0);
     return;
   }
 
   grpc_endpoint_write(exec_ctx, ep->wrapped_ep, &ep->output_buffer, cb);
+  GPR_TIMER_END("secure_endpoint.endpoint_write", 0);
 }
 
 static void endpoint_shutdown(grpc_exec_ctx *exec_ctx,

src/core/lib/surface/channel_ping.c

@@ -61,6 +61,8 @@ static void ping_done(grpc_exec_ctx *exec_ctx, void *arg, grpc_error *error) {
 
 void grpc_channel_ping(grpc_channel *channel, grpc_completion_queue *cq,
                        void *tag, void *reserved) {
+  GRPC_API_TRACE("grpc_channel_ping(channel=%p, cq=%p, tag=%p, reserved=%p)", 4,
+                 (channel, cq, tag, reserved));
   grpc_transport_op *op = grpc_make_transport_op(NULL);
   ping_result *pr = gpr_malloc(sizeof(*pr));
   grpc_channel_element *top_elem =

src/core/lib/surface/lame_client.c

@@ -97,14 +97,14 @@ static void lame_start_transport_op(grpc_exec_ctx *exec_ctx,
     grpc_exec_ctx_sched(exec_ctx, op->on_connectivity_state_change,
                         GRPC_ERROR_NONE, NULL);
   }
-  if (op->on_consumed != NULL) {
-    grpc_exec_ctx_sched(exec_ctx, op->on_consumed, GRPC_ERROR_NONE, NULL);
-  }
   if (op->send_ping != NULL) {
     grpc_exec_ctx_sched(exec_ctx, op->send_ping,
                         GRPC_ERROR_CREATE("lame client channel"), NULL);
   }
   GRPC_ERROR_UNREF(op->disconnect_with_error);
+  if (op->on_consumed != NULL) {
+    grpc_exec_ctx_sched(exec_ctx, op->on_consumed, GRPC_ERROR_NONE, NULL);
+  }
 }
 
 static void init_call_elem(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,

src/core/lib/surface/server.c

@@ -428,7 +428,8 @@ static void finish_destroy_channel(grpc_exec_ctx *exec_ctx, void *cd,
   server_unref(exec_ctx, server);
 }
 
-static void destroy_channel(grpc_exec_ctx *exec_ctx, channel_data *chand) {
+static void destroy_channel(grpc_exec_ctx *exec_ctx, channel_data *chand,
+                            grpc_error *error) {
   if (is_channel_orphaned(chand)) return;
   GPR_ASSERT(chand->server != NULL);
   orphan_channel(chand);
@@ -444,6 +445,8 @@ static void destroy_channel(grpc_exec_ctx *exec_ctx, channel_data *chand) {
                        grpc_channel_stack_element(
                            grpc_channel_get_channel_stack(chand->channel), 0),
                        op);
+
+  GRPC_LOG_IF_ERROR("disconnecting client", error);
 }
 
 static void cpstr(char **dest, size_t *capacity, grpc_mdstr *value) {
@@ -845,7 +848,7 @@ static void channel_connectivity_changed(grpc_exec_ctx *exec_ctx, void *cd,
                          op);
   } else {
     gpr_mu_lock(&server->mu_global);
-    destroy_channel(exec_ctx, chand);
+    destroy_channel(exec_ctx, chand, GRPC_ERROR_REF(error));
     gpr_mu_unlock(&server->mu_global);
     GRPC_CHANNEL_INTERNAL_UNREF(exec_ctx, chand->channel, "connectivity");
   }

test/core/surface/lame_client_test.c

@@ -49,8 +49,8 @@ static void *tag(intptr_t x) { return (void *)x; }
 
 void verify_connectivity(grpc_exec_ctx *exec_ctx, void *arg,
                          grpc_error *error) {
-  grpc_transport_op *op = arg;
+  grpc_connectivity_state *state = arg;
-  GPR_ASSERT(GRPC_CHANNEL_SHUTDOWN == *op->connectivity_state);
+  GPR_ASSERT(GRPC_CHANNEL_SHUTDOWN == *state);
   GPR_ASSERT(error == GRPC_ERROR_NONE);
 }
 
@@ -62,7 +62,7 @@ void test_transport_op(grpc_channel *channel) {
   grpc_connectivity_state state = GRPC_CHANNEL_IDLE;
   grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
 
-  grpc_closure_init(&transport_op_cb, verify_connectivity, &op);
+  grpc_closure_init(&transport_op_cb, verify_connectivity, &state);
 
   op = grpc_make_transport_op(NULL);
   op->on_connectivity_state_change = &transport_op_cb;