From 556e5ae525c4fbcffaebc7f0f60b3f0192e3003a Mon Sep 17 00:00:00 2001 From: Craig Tiller Date: Mon, 16 May 2016 11:00:33 -0700 Subject: [PATCH] Fix accelerated wakeups We can end up in situations where a pollset needs to kick itself. This is supposed to be an accelerated codepath, however a bug crept in whereby we missed the opportunity to do so, resulting in needing to round trip these wakeups redundantly through the OS and wake other threads unnecessarily. --- src/core/lib/iomgr/ev_poll_posix.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/src/core/lib/iomgr/ev_poll_posix.c b/src/core/lib/iomgr/ev_poll_posix.c index d1752327a2b..e91ae402122 100644 --- a/src/core/lib/iomgr/ev_poll_posix.c +++ b/src/core/lib/iomgr/ev_poll_posix.c @@ -824,6 +824,7 @@ static void pollset_work(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset, re-evaluate our pollers (this allows poll() based pollers to ensure they don't miss wakeups) */ keep_polling = 1; + gpr_tls_set(&g_current_thread_poller, (intptr_t)pollset); while (keep_polling) { keep_polling = 0; if (!pollset->kicked_without_pollers) { @@ -832,7 +833,6 @@ static void pollset_work(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset, added_worker = 1; gpr_tls_set(&g_current_thread_worker, (intptr_t)&worker); } - gpr_tls_set(&g_current_thread_poller, (intptr_t)pollset); GPR_TIMER_BEGIN("maybe_work_and_unlock", 0); #define POLLOUT_CHECK (POLLOUT | POLLHUP | POLLERR) #define POLLIN_CHECK (POLLIN | POLLHUP | POLLERR) @@ -926,7 +926,6 @@ static void pollset_work(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset, gpr_free(watchers); GPR_TIMER_END("maybe_work_and_unlock", 0); locked = 0; - gpr_tls_set(&g_current_thread_poller, 0); } else { GPR_TIMER_MARK("pollset_work.kicked_without_pollers", 0); pollset->kicked_without_pollers = 0; @@ -958,6 +957,7 @@ static void pollset_work(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset, now = gpr_now(now.clock_type); } } + gpr_tls_set(&g_current_thread_poller, 0); if (added_worker) { remove_worker(pollset, &worker); gpr_tls_set(&g_current_thread_worker, 0);