Enable epoll1 poller

src/core/lib/iomgr/ev_epoll1_linux.c

@@ -668,9 +668,9 @@ static void end_worker(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
       }
     } else {
       gpr_atm_no_barrier_store(&g_active_poller, 0);
-      gpr_mu_unlock(&pollset->mu);
       size_t poller_neighbourhood_idx =
           (size_t)(pollset->neighbourhood - g_neighbourhoods);
+      gpr_mu_unlock(&pollset->mu);
       bool found_worker = false;
       bool scan_state[MAX_NEIGHBOURHOODS];
       for (size_t i = 0; !found_worker && i < g_num_neighbourhoods; i++) {
@@ -948,9 +948,6 @@ static const grpc_event_engine_vtable vtable = {
 /* It is possible that GLIBC has epoll but the underlying kernel doesn't.
  * Create a dummy epoll_fd to make sure epoll support is available */
 const grpc_event_engine_vtable *grpc_init_epoll1_linux(bool explicit_request) {
-  /* TODO(ctiller): temporary, until this stabilizes */
-  if (!explicit_request) return NULL;
-
   if (!grpc_has_wakeup_fd()) {
     return NULL;
   }

src/core/lib/iomgr/ev_epollsig_linux.c

@@ -1937,7 +1937,7 @@ const grpc_event_engine_vtable *grpc_init_epollsig_linux(
   if (!is_grpc_wakeup_signal_initialized) {
     /* TODO(ctiller): when other epoll engines are ready, remove the true || to
      * force this to be explitly chosen if needed */
-    if (true || explicit_request) {
+    if (explicit_request) {
       grpc_use_signal(SIGRTMIN + 6);
     } else {
       return NULL;

tools/run_tests/run_tests.py

@@ -75,8 +75,8 @@ _FORCE_ENVIRON_FOR_WRAPPERS = {
 
 
 _POLLING_STRATEGIES = {
-  'linux': ['epollsig', 'poll', 'poll-cv'],
+  'linux': ['epoll1', 'epollsig', 'poll', 'poll-cv'],
-# TODO(ctiller, sreecha): enable epoll1, epollex, epoll-thread-pool
+# TODO(ctiller, sreecha): enable epollex, epoll-thread-pool
   'mac': ['poll'],
 }