Add counters, fix race

src/core/lib/debug/stats_data.c

@@ -20,5 +20,6 @@
 
 #include "src/core/lib/debug/stats_data.h"
 const char *grpc_stats_counter_name[GRPC_STATS_COUNTER_COUNT] = {
-    "client_calls_created", "server_calls_created",
+    "client_calls_created", "server_calls_created", "syscall_write",
+    "syscall_read",         "syscall_poll",         "syscall_wait",
 };

src/core/lib/debug/stats_data.h

@@ -24,12 +24,24 @@
 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 */

src/core/lib/debug/stats_data.yaml

@@ -3,3 +3,7 @@
 
 - counter: client_calls_created
 - counter: server_calls_created
+- counter: syscall_write
+- counter: syscall_read
+- counter: syscall_poll
+- counter: syscall_wait

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"
@@ -474,6 +475,7 @@ 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(g_epfd, events, MAX_EPOLL_EVENTS, timeout);
   } while (r < 0 && errno == EINTR);
   if (timeout != 0) {

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"
@@ -1307,6 +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;
     }
@@ -1392,6 +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;

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;

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) {

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"
@@ -1237,6 +1238,7 @@ 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;

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"
@@ -958,6 +959,7 @@ 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;
 

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)));

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)) {

test/cpp/microbenchmarks/bm_cq_multiple_threads.cc

@@ -38,6 +38,8 @@ struct grpc_pollset {
 namespace grpc {
 namespace testing {
 
+auto& force_library_initialization = Library::get();
+
 static void* g_tag = (void*)(intptr_t)10;  // Some random number
 static grpc_completion_queue* g_cq;
 static grpc_event_engine_vtable g_vtable;