Merge pull request #11873 from ctiller/stats

Add a simple stats framework to gRPC C core

16 files changed, 232 insertions, 6 deletions

diff --git a/src/core/lib/debug/stats.c b/src/core/lib/debug/stats.c
new file mode 100644
index 0000000000..4dbd94c724
--- /dev/null
+++ b/src/core/lib/debug/stats.c
@@ -0,0 +1,67 @@
+/*
+ *
+ * Copyright 2017 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+#include "src/core/lib/debug/stats.h"
+
+#include <inttypes.h>
+#include <string.h>
+
+#include <grpc/support/alloc.h>
+#include <grpc/support/string_util.h>
+#include <grpc/support/useful.h>
+
+#include "src/core/lib/support/string.h"
+
+grpc_stats_data *grpc_stats_per_cpu_storage = NULL;
+static size_t g_num_cores;
+
+void grpc_stats_init(void) {
+  g_num_cores = GPR_MAX(1, gpr_cpu_num_cores());
+  grpc_stats_per_cpu_storage =
+      gpr_zalloc(sizeof(grpc_stats_data) * g_num_cores);
+}
+
+void grpc_stats_shutdown(void) { gpr_free(grpc_stats_per_cpu_storage); }
+
+void grpc_stats_collect(grpc_stats_data *output) {
+  memset(output, 0, sizeof(*output));
+  for (size_t core = 0; core < g_num_cores; core++) {
+    for (size_t i = 0; i < GRPC_STATS_COUNTER_COUNT; i++) {
+      output->counters[i] += gpr_atm_no_barrier_load(
+          &grpc_stats_per_cpu_storage[core].counters[i]);
+    }
+  }
+}
+
+char *grpc_stats_data_as_json(const grpc_stats_data *data) {
+  gpr_strvec v;
+  char *tmp;
+  bool is_first = true;
+  gpr_strvec_init(&v);
+  gpr_strvec_add(&v, gpr_strdup("{"));
+  for (size_t i = 0; i < GRPC_STATS_COUNTER_COUNT; i++) {
+    gpr_asprintf(&tmp, "%s\"%s\": %" PRIdPTR, is_first ? "" : ", ",
+                 grpc_stats_counter_name[i], data->counters[i]);
+    gpr_strvec_add(&v, tmp);
+    is_first = false;
+  }
+  gpr_strvec_add(&v, gpr_strdup("}"));
+  tmp = gpr_strvec_flatten(&v, NULL);
+  gpr_strvec_destroy(&v);
+  return tmp;
+}
diff --git a/src/core/lib/debug/stats.h b/src/core/lib/debug/stats.h
new file mode 100644
index 0000000000..563b108dff
--- /dev/null
+++ b/src/core/lib/debug/stats.h
@@ -0,0 +1,44 @@
+/*
+ *
+ * Copyright 2017 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+#ifndef GRPC_CORE_LIB_DEBUG_STATS_H
+#define GRPC_CORE_LIB_DEBUG_STATS_H
+
+#include <grpc/support/atm.h>
+#include "src/core/lib/debug/stats_data.h"
+#include "src/core/lib/iomgr/exec_ctx.h"
+
+typedef struct grpc_stats_data {
+  gpr_atm counters[GRPC_STATS_COUNTER_COUNT];
+} grpc_stats_data;
+
+extern grpc_stats_data *grpc_stats_per_cpu_storage;
+
+#define GRPC_THREAD_STATS_DATA(exec_ctx) \
+  (&grpc_stats_per_cpu_storage[(exec_ctx)->starting_cpu])
+
+#define GRPC_STATS_INC_COUNTER(exec_ctx, ctr) \
+  (gpr_atm_no_barrier_fetch_add(              \
+      &GRPC_THREAD_STATS_DATA((exec_ctx))->counters[(ctr)], 1))
+
+void grpc_stats_init(void);
+void grpc_stats_shutdown(void);
+void grpc_stats_collect(grpc_stats_data *output);
+char *grpc_stats_data_as_json(const grpc_stats_data *data);
+
+#endif
diff --git a/src/core/lib/debug/stats_data.c b/src/core/lib/debug/stats_data.c
new file mode 100644
index 0000000000..2203358a7e
--- /dev/null
+++ b/src/core/lib/debug/stats_data.c
@@ -0,0 +1,25 @@
+/*
+ * Copyright 2017 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/*
+ * Automatically generated by tools/codegen/core/gen_stats_data.py
+ */
+
+#include "src/core/lib/debug/stats_data.h"
+const char *grpc_stats_counter_name[GRPC_STATS_COUNTER_COUNT] = {
+    "client_calls_created", "server_calls_created", "syscall_write",
+    "syscall_read",         "syscall_poll",         "syscall_wait",
+};
diff --git a/src/core/lib/debug/stats_data.h b/src/core/lib/debug/stats_data.h
new file mode 100644
index 0000000000..c9c2f65c30
--- /dev/null
+++ b/src/core/lib/debug/stats_data.h
@@ -0,0 +1,47 @@
+/*
+ * Copyright 2017 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/*
+ * Automatically generated by tools/codegen/core/gen_stats_data.py
+ */
+
+#ifndef GRPC_CORE_LIB_DEBUG_STATS_DATA_H
+#define GRPC_CORE_LIB_DEBUG_STATS_DATA_H
+
+typedef enum {
+  GRPC_STATS_COUNTER_CLIENT_CALLS_CREATED,
+  GRPC_STATS_COUNTER_SERVER_CALLS_CREATED,
+  GRPC_STATS_COUNTER_SYSCALL_WRITE,
+  GRPC_STATS_COUNTER_SYSCALL_READ,
+  GRPC_STATS_COUNTER_SYSCALL_POLL,
+  GRPC_STATS_COUNTER_SYSCALL_WAIT,
+  GRPC_STATS_COUNTER_COUNT
+} grpc_stats_counters;
+#define GRPC_STATS_INC_CLIENT_CALLS_CREATED(exec_ctx) \
+  GRPC_STATS_INC_COUNTER((exec_ctx), GRPC_STATS_COUNTER_CLIENT_CALLS_CREATED)
+#define GRPC_STATS_INC_SERVER_CALLS_CREATED(exec_ctx) \
+  GRPC_STATS_INC_COUNTER((exec_ctx), GRPC_STATS_COUNTER_SERVER_CALLS_CREATED)
+#define GRPC_STATS_INC_SYSCALL_WRITE(exec_ctx) \
+  GRPC_STATS_INC_COUNTER((exec_ctx), GRPC_STATS_COUNTER_SYSCALL_WRITE)
+#define GRPC_STATS_INC_SYSCALL_READ(exec_ctx) \
+  GRPC_STATS_INC_COUNTER((exec_ctx), GRPC_STATS_COUNTER_SYSCALL_READ)
+#define GRPC_STATS_INC_SYSCALL_POLL(exec_ctx) \
+  GRPC_STATS_INC_COUNTER((exec_ctx), GRPC_STATS_COUNTER_SYSCALL_POLL)
+#define GRPC_STATS_INC_SYSCALL_WAIT(exec_ctx) \
+  GRPC_STATS_INC_COUNTER((exec_ctx), GRPC_STATS_COUNTER_SYSCALL_WAIT)
+extern const char *grpc_stats_counter_name[GRPC_STATS_COUNTER_COUNT];
+
+#endif /* GRPC_CORE_LIB_DEBUG_STATS_DATA_H */
diff --git a/src/core/lib/debug/stats_data.yaml b/src/core/lib/debug/stats_data.yaml
new file mode 100644
index 0000000000..8afe48f5cd
--- /dev/null
+++ b/src/core/lib/debug/stats_data.yaml
@@ -0,0 +1,9 @@
+# Stats data declaration
+# use tools/codegen/core/gen_stats_data.py to turn this into stats_data.h
+
+- counter: client_calls_created
+- counter: server_calls_created
+- counter: syscall_write
+- counter: syscall_read
+- counter: syscall_poll
+- counter: syscall_wait
diff --git a/src/core/lib/iomgr/ev_epoll1_linux.c b/src/core/lib/iomgr/ev_epoll1_linux.c
index 8b0a65006e..7f053fa728 100644
--- a/src/core/lib/iomgr/ev_epoll1_linux.c
+++ b/src/core/lib/iomgr/ev_epoll1_linux.c
@@ -39,6 +39,7 @@
 #include <grpc/support/tls.h>
 #include <grpc/support/useful.h>
 
+#include "src/core/lib/debug/stats.h"
 #include "src/core/lib/iomgr/ev_posix.h"
 #include "src/core/lib/iomgr/iomgr_internal.h"
 #include "src/core/lib/iomgr/lockfree_event.h"
@@ -635,6 +636,7 @@ static grpc_error *do_epoll_wait(grpc_exec_ctx *exec_ctx, grpc_pollset *ps,
     GRPC_SCHEDULING_START_BLOCKING_REGION;
   }
   do {
+    GRPC_STATS_INC_SYSCALL_POLL(exec_ctx);
     r = epoll_wait(g_epoll_set.epfd, g_epoll_set.events, MAX_EPOLL_EVENTS,
                    timeout);
   } while (r < 0 && errno == EINTR);
diff --git a/src/core/lib/iomgr/ev_epoll_limited_pollers_linux.c b/src/core/lib/iomgr/ev_epoll_limited_pollers_linux.c
index f2f3e15704..e2e3cd9003 100644
--- a/src/core/lib/iomgr/ev_epoll_limited_pollers_linux.c
+++ b/src/core/lib/iomgr/ev_epoll_limited_pollers_linux.c
@@ -40,6 +40,7 @@
 #include <grpc/support/tls.h>
 #include <grpc/support/useful.h>
 
+#include "src/core/lib/debug/stats.h"
 #include "src/core/lib/debug/trace.h"
 #include "src/core/lib/iomgr/ev_posix.h"
 #include "src/core/lib/iomgr/iomgr_internal.h"
@@ -1286,7 +1287,8 @@ static void pollset_destroy(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset) {
 }
 
 /* NOTE: This function may modify 'now' */
-static bool acquire_polling_lease(grpc_pollset_worker *worker,
+static bool acquire_polling_lease(grpc_exec_ctx *exec_ctx,
+                                  grpc_pollset_worker *worker,
                                   polling_island *pi, gpr_timespec deadline,
                                   gpr_timespec *now) {
   bool is_lease_acquired = false;
@@ -1306,6 +1308,7 @@ static bool acquire_polling_lease(grpc_pollset_worker *worker,
     } else {
       struct timespec sigwait_timeout = millis_to_timespec(timeout_ms);
       GRPC_SCHEDULING_START_BLOCKING_REGION;
+      GRPC_STATS_INC_SYSCALL_WAIT(exec_ctx);
       ret = sigtimedwait(&g_wakeup_sig_set, NULL, &sigwait_timeout);
       GRPC_SCHEDULING_END_BLOCKING_REGION;
     }
@@ -1378,7 +1381,7 @@ static void pollset_do_epoll_pwait(grpc_exec_ctx *exec_ctx, int epoll_fd,
                                    sigset_t *sig_mask, grpc_error **error) {
   /* Only g_max_pollers_per_pi threads can be doing polling in parallel.
      If we cannot get a lease, we cannot continue to do epoll_pwait() */
-  if (!acquire_polling_lease(worker, pi, deadline, &now)) {
+  if (!acquire_polling_lease(exec_ctx, worker, pi, deadline, &now)) {
     return;
   }
 
@@ -1391,6 +1394,7 @@ static void pollset_do_epoll_pwait(grpc_exec_ctx *exec_ctx, int epoll_fd,
   int timeout_ms = poll_deadline_to_millis_timeout(deadline, now);
 
   GRPC_SCHEDULING_START_BLOCKING_REGION;
+  GRPC_STATS_INC_SYSCALL_POLL(exec_ctx);
   ep_rv =
       epoll_pwait(epoll_fd, ep_ev, GRPC_EPOLL_MAX_EVENTS, timeout_ms, sig_mask);
   GRPC_SCHEDULING_END_BLOCKING_REGION;
diff --git a/src/core/lib/iomgr/ev_epoll_thread_pool_linux.c b/src/core/lib/iomgr/ev_epoll_thread_pool_linux.c
index 07c8eadf4f..ddb8c74d2d 100644
--- a/src/core/lib/iomgr/ev_epoll_thread_pool_linux.c
+++ b/src/core/lib/iomgr/ev_epoll_thread_pool_linux.c
@@ -41,6 +41,7 @@
 #include <grpc/support/tls.h>
 #include <grpc/support/useful.h>
 
+#include "src/core/lib/debug/stats.h"
 #include "src/core/lib/iomgr/ev_posix.h"
 #include "src/core/lib/iomgr/iomgr_internal.h"
 #include "src/core/lib/iomgr/lockfree_event.h"
@@ -776,6 +777,7 @@ static void do_epoll_wait(grpc_exec_ctx *exec_ctx, int epoll_fd, epoll_set *eps,
 
   GRPC_SCHEDULING_START_BLOCKING_REGION;
   acquire_epoll_lease(eps);
+  GRPC_STATS_INC_SYSCALL_POLL(exec_ctx);
   ep_rv = epoll_wait(epoll_fd, ep_ev, GRPC_EPOLL_MAX_EVENTS, timeout_ms);
   release_epoll_lease(eps);
   GRPC_SCHEDULING_END_BLOCKING_REGION;
diff --git a/src/core/lib/iomgr/ev_epollex_linux.c b/src/core/lib/iomgr/ev_epollex_linux.c
index 1f4adea5d4..0e42f76af3 100644
--- a/src/core/lib/iomgr/ev_epollex_linux.c
+++ b/src/core/lib/iomgr/ev_epollex_linux.c
@@ -37,6 +37,7 @@
 #include <grpc/support/tls.h>
 #include <grpc/support/useful.h>
 
+#include "src/core/lib/debug/stats.h"
 #include "src/core/lib/iomgr/ev_posix.h"
 #include "src/core/lib/iomgr/iomgr_internal.h"
 #include "src/core/lib/iomgr/is_epollexclusive_available.h"
@@ -814,6 +815,7 @@ static grpc_error *pollset_epoll(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
   }
   int r;
   do {
+    GRPC_STATS_INC_SYSCALL_POLL(exec_ctx);
     r = epoll_wait(p->epfd, pollset->events, MAX_EPOLL_EVENTS, timeout);
   } while (r < 0 && errno == EINTR);
   if (timeout != 0) {
diff --git a/src/core/lib/iomgr/ev_epollsig_linux.c b/src/core/lib/iomgr/ev_epollsig_linux.c
index fad12ff65c..59c7cdc285 100644
--- a/src/core/lib/iomgr/ev_epollsig_linux.c
+++ b/src/core/lib/iomgr/ev_epollsig_linux.c
@@ -39,6 +39,7 @@
 #include <grpc/support/tls.h>
 #include <grpc/support/useful.h>
 
+#include "src/core/lib/debug/stats.h"
 #include "src/core/lib/iomgr/ev_posix.h"
 #include "src/core/lib/iomgr/iomgr_internal.h"
 #include "src/core/lib/iomgr/lockfree_event.h"
@@ -1236,6 +1237,7 @@ static void pollset_work_and_unlock(grpc_exec_ctx *exec_ctx,
   g_current_thread_polling_island = pi;
 
   GRPC_SCHEDULING_START_BLOCKING_REGION;
+  GRPC_STATS_INC_SYSCALL_POLL(exec_ctx);
   ep_rv =
       epoll_pwait(epoll_fd, ep_ev, GRPC_EPOLL_MAX_EVENTS, timeout_ms, sig_mask);
   GRPC_SCHEDULING_END_BLOCKING_REGION;
diff --git a/src/core/lib/iomgr/ev_poll_posix.c b/src/core/lib/iomgr/ev_poll_posix.c
index 9472a8e520..fbd265f3ce 100644
--- a/src/core/lib/iomgr/ev_poll_posix.c
+++ b/src/core/lib/iomgr/ev_poll_posix.c
@@ -36,6 +36,7 @@
 #include <grpc/support/tls.h>
 #include <grpc/support/useful.h>
 
+#include "src/core/lib/debug/stats.h"
 #include "src/core/lib/iomgr/iomgr_internal.h"
 #include "src/core/lib/iomgr/timer.h"
 #include "src/core/lib/iomgr/wakeup_fd_cv.h"
@@ -983,6 +984,7 @@ static grpc_error *pollset_work(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
       /* TODO(vpai): Consider first doing a 0 timeout poll here to avoid
          even going into the blocking annotation if possible */
       GRPC_SCHEDULING_START_BLOCKING_REGION;
+      GRPC_STATS_INC_SYSCALL_POLL(exec_ctx);
       r = grpc_poll_function(pfds, pfd_count, timeout);
       GRPC_SCHEDULING_END_BLOCKING_REGION;
 
diff --git a/src/core/lib/iomgr/exec_ctx.h b/src/core/lib/iomgr/exec_ctx.h
index a0d2a965d5..c89792c8c4 100644
--- a/src/core/lib/iomgr/exec_ctx.h
+++ b/src/core/lib/iomgr/exec_ctx.h
@@ -19,6 +19,7 @@
 #ifndef GRPC_CORE_LIB_IOMGR_EXEC_CTX_H
 #define GRPC_CORE_LIB_IOMGR_EXEC_CTX_H
 
+#include <grpc/support/cpu.h>
 #include "src/core/lib/iomgr/closure.h"
 
 /* #define GRPC_EXECUTION_CONTEXT_SANITIZER 1 */
@@ -62,6 +63,7 @@ struct grpc_exec_ctx {
   /** last active combiner in the active combiner list */
   grpc_combiner *last_combiner;
   uintptr_t flags;
+  unsigned starting_cpu;
   void *check_ready_to_finish_arg;
   bool (*check_ready_to_finish)(grpc_exec_ctx *exec_ctx, void *arg);
 };
@@ -69,7 +71,10 @@ struct grpc_exec_ctx {
 /* initializer for grpc_exec_ctx:
    prefer to use GRPC_EXEC_CTX_INIT whenever possible */
 #define GRPC_EXEC_CTX_INITIALIZER(flags, finish_check, finish_check_arg) \
-  { GRPC_CLOSURE_LIST_INIT, NULL, NULL, flags, finish_check_arg, finish_check }
+  {                                                                      \
+    GRPC_CLOSURE_LIST_INIT, NULL, NULL, flags, gpr_cpu_current_cpu(),    \
+        finish_check_arg, finish_check                                   \
+  }
 
 /* initialize an execution context at the top level of an API call into grpc
    (this is safe to use elsewhere, though possibly not as efficient) */
diff --git a/src/core/lib/iomgr/iocp_windows.c b/src/core/lib/iomgr/iocp_windows.c
index e343f8a794..c082179c0b 100644
--- a/src/core/lib/iomgr/iocp_windows.c
+++ b/src/core/lib/iomgr/iocp_windows.c
@@ -27,6 +27,7 @@
 #include <grpc/support/log_windows.h>
 #include <grpc/support/thd.h>
 
+#include "src/core/lib/debug/stats.h"
 #include "src/core/lib/iomgr/iocp_windows.h"
 #include "src/core/lib/iomgr/iomgr_internal.h"
 #include "src/core/lib/iomgr/socket_windows.h"
@@ -65,6 +66,7 @@ grpc_iocp_work_status grpc_iocp_work(grpc_exec_ctx *exec_ctx,
   LPOVERLAPPED overlapped;
   grpc_winsocket *socket;
   grpc_winsocket_callback_info *info;
+  GRPC_STATS_INC_SYSCALL_POLL(exec_ctx);
   success = GetQueuedCompletionStatus(
       g_iocp, &bytes, &completion_key, &overlapped,
       deadline_to_millis_timeout(deadline, gpr_now(deadline.clock_type)));
diff --git a/src/core/lib/iomgr/tcp_posix.c b/src/core/lib/iomgr/tcp_posix.c
index 2f543fd8a9..7e789cc5b5 100644
--- a/src/core/lib/iomgr/tcp_posix.c
+++ b/src/core/lib/iomgr/tcp_posix.c
@@ -40,6 +40,7 @@
 #include <grpc/support/useful.h>
 
 #include "src/core/lib/channel/channel_args.h"
+#include "src/core/lib/debug/stats.h"
 #include "src/core/lib/debug/trace.h"
 #include "src/core/lib/iomgr/ev_posix.h"
 #include "src/core/lib/profiling/timers.h"
@@ -258,6 +259,7 @@ static void tcp_do_read(grpc_exec_ctx *exec_ctx, grpc_tcp *tcp) {
 
   GPR_TIMER_BEGIN("recvmsg", 0);
   do {
+    GRPC_STATS_INC_SYSCALL_READ(exec_ctx);
     read_bytes = recvmsg(tcp->fd, &msg, 0);
   } while (read_bytes < 0 && errno == EINTR);
   GPR_TIMER_END("recvmsg", read_bytes >= 0);
@@ -361,7 +363,8 @@ static void tcp_read(grpc_exec_ctx *exec_ctx, grpc_endpoint *ep,
 
 /* returns true if done, false if pending; if returning true, *error is set */
 #define MAX_WRITE_IOVEC 1000
-static bool tcp_flush(grpc_tcp *tcp, grpc_error **error) {
+static bool tcp_flush(grpc_exec_ctx *exec_ctx, grpc_tcp *tcp,
+                      grpc_error **error) {
   struct msghdr msg;
   struct iovec iov[MAX_WRITE_IOVEC];
   msg_iovlen_type iov_size;
@@ -403,6 +406,7 @@ static bool tcp_flush(grpc_tcp *tcp, grpc_error **error) {
     GPR_TIMER_BEGIN("sendmsg", 1);
     do {
       /* TODO(klempner): Cork if this is a partial write */
+      GRPC_STATS_INC_SYSCALL_WRITE(exec_ctx);
       sent_length = sendmsg(tcp->fd, &msg, SENDMSG_FLAGS);
     } while (sent_length < 0 && errno == EINTR);
     GPR_TIMER_END("sendmsg", 0);
@@ -459,7 +463,7 @@ static void tcp_handle_write(grpc_exec_ctx *exec_ctx, void *arg /* grpc_tcp */,
     return;
   }
 
-  if (!tcp_flush(tcp, &error)) {
+  if (!tcp_flush(exec_ctx, tcp, &error)) {
     if (GRPC_TRACER_ON(grpc_tcp_trace)) {
       gpr_log(GPR_DEBUG, "write: delayed");
     }
@@ -510,7 +514,7 @@ static void tcp_write(grpc_exec_ctx *exec_ctx, grpc_endpoint *ep,
   tcp->outgoing_slice_idx = 0;
   tcp->outgoing_byte_idx = 0;
 
-  if (!tcp_flush(tcp, &error)) {
+  if (!tcp_flush(exec_ctx, tcp, &error)) {
     TCP_REF(tcp, "write");
     tcp->write_cb = cb;
     if (GRPC_TRACER_ON(grpc_tcp_trace)) {
diff --git a/src/core/lib/surface/call.c b/src/core/lib/surface/call.c
index 62d542d2c5..e68c201134 100644
--- a/src/core/lib/surface/call.c
+++ b/src/core/lib/surface/call.c
@@ -32,6 +32,7 @@
 
 #include "src/core/lib/channel/channel_stack.h"
 #include "src/core/lib/compression/algorithm_metadata.h"
+#include "src/core/lib/debug/stats.h"
 #include "src/core/lib/iomgr/timer.h"
 #include "src/core/lib/profiling/timers.h"
 #include "src/core/lib/slice/slice_internal.h"
@@ -334,6 +335,11 @@ grpc_error *grpc_call_create(grpc_exec_ctx *exec_ctx,
   /* Always support no compression */
   GPR_BITSET(&call->encodings_accepted_by_peer, GRPC_COMPRESS_NONE);
   call->is_client = args->server_transport_data == NULL;
+  if (call->is_client) {
+    GRPC_STATS_INC_CLIENT_CALLS_CREATED(exec_ctx);
+  } else {
+    GRPC_STATS_INC_SERVER_CALLS_CREATED(exec_ctx);
+  }
   call->stream_op_payload.context = call->context;
   grpc_slice path = grpc_empty_slice();
   if (call->is_client) {
diff --git a/src/core/lib/surface/init.c b/src/core/lib/surface/init.c
index d199ac060e..898476daee 100644
--- a/src/core/lib/surface/init.c
+++ b/src/core/lib/surface/init.c
@@ -28,6 +28,7 @@
 #include "src/core/lib/channel/channel_stack.h"
 #include "src/core/lib/channel/connected_channel.h"
 #include "src/core/lib/channel/handshaker_registry.h"
+#include "src/core/lib/debug/stats.h"
 #include "src/core/lib/debug/trace.h"
 #include "src/core/lib/http/parser.h"
 #include "src/core/lib/iomgr/combiner.h"
@@ -118,6 +119,7 @@ void grpc_init(void) {
   gpr_mu_lock(&g_init_mu);
   if (++g_initializations == 1) {
     gpr_time_init();
+    grpc_stats_init();
     grpc_slice_intern_init();
     grpc_mdctx_global_init();
     grpc_channel_init_init();
@@ -186,6 +188,7 @@ void grpc_shutdown(void) {
     grpc_mdctx_global_shutdown(&exec_ctx);
     grpc_handshaker_factory_registry_shutdown(&exec_ctx);
     grpc_slice_intern_shutdown();
+    grpc_stats_shutdown();
   }
   gpr_mu_unlock(&g_init_mu);
   grpc_exec_ctx_finish(&exec_ctx);