Remove return status from maybe_work.

Since alarm checks may mutate work deadlines for pollsets, the value
returned from maybe_work is meaningless. Instead, maybe pollset_work
always return 1 if maybe_work is invoked, and then redo the deadline
check _on the next call_ to pollset_work.

src/core/iomgr/pollset_multipoller_with_epoll.c

@@ -83,7 +83,7 @@ static void multipoll_with_epoll_pollset_del_fd(grpc_pollset *pollset,
 /* TODO(klempner): We probably want to turn this down a bit */
 #define GRPC_EPOLL_MAX_EVENTS 1000
 
-static int multipoll_with_epoll_pollset_maybe_work(
+static void multipoll_with_epoll_pollset_maybe_work(
     grpc_pollset *pollset, gpr_timespec deadline, gpr_timespec now,
     int allow_synchronous_callback) {
   struct epoll_event ep_ev[GRPC_EPOLL_MAX_EVENTS];
@@ -133,7 +133,6 @@ static int multipoll_with_epoll_pollset_maybe_work(
 
   gpr_mu_lock(&pollset->mu);
   pollset->counter -= 1;
-  return 1;
 }
 
 static void multipoll_with_epoll_pollset_finish_shutdown(

src/core/iomgr/pollset_multipoller_with_poll_posix.c

@@ -103,7 +103,7 @@ static void end_polling(grpc_pollset *pollset) {
   }
 }
 
-static int multipoll_with_poll_pollset_maybe_work(
+static void multipoll_with_poll_pollset_maybe_work(
     grpc_pollset *pollset, gpr_timespec deadline, gpr_timespec now,
     int allow_synchronous_callback) {
   int timeout;
@@ -126,7 +126,7 @@ static int multipoll_with_poll_pollset_maybe_work(
   kfd = grpc_pollset_kick_pre_poll(&pollset->kick_state);
   if (kfd == NULL) {
     /* Already kicked */
-    return 1;
+    return;
   }
   h->pfds[0].fd = GRPC_POLLSET_KICK_GET_FD(kfd);
   h->pfds[0].events = POLLIN;
@@ -154,7 +154,7 @@ static int multipoll_with_poll_pollset_maybe_work(
   h->del_count = 0;
   if (h->pfd_count == 0) {
     end_polling(pollset);
-    return 0;
+    return;
   }
   pollset->counter++;
   gpr_mu_unlock(&pollset->mu);
@@ -191,8 +191,6 @@ static int multipoll_with_poll_pollset_maybe_work(
 
   gpr_mu_lock(&pollset->mu);
   pollset->counter--;
-
-  return 1;
 }
 
 static void multipoll_with_poll_pollset_kick(grpc_pollset *p) {

src/core/iomgr/pollset_posix.c

@@ -123,7 +123,6 @@ static void finish_shutdown(grpc_pollset *pollset) {
 int grpc_pollset_work(grpc_pollset *pollset, gpr_timespec deadline) {
   /* pollset->mu already held */
   gpr_timespec now = gpr_now();
-  int r;
   if (gpr_time_cmp(now, deadline) > 0) {
     return 0;
   }
@@ -137,7 +136,7 @@ int grpc_pollset_work(grpc_pollset *pollset, gpr_timespec deadline) {
     return 1;
   }
   gpr_tls_set(&g_current_thread_poller, (gpr_intptr)pollset);
-  r = pollset->vtable->maybe_work(pollset, deadline, now, 1);
+  pollset->vtable->maybe_work(pollset, deadline, now, 1);
   gpr_tls_set(&g_current_thread_poller, 0);
   if (pollset->shutting_down) {
     if (pollset->counter > 0) {
@@ -153,7 +152,7 @@ int grpc_pollset_work(grpc_pollset *pollset, gpr_timespec deadline) {
       gpr_mu_lock(&pollset->mu);
     }
   }
-  return r;
+  return 1;
 }
 
 void grpc_pollset_shutdown(grpc_pollset *pollset,
@@ -338,9 +337,9 @@ static void basic_pollset_del_fd(grpc_pollset *pollset, grpc_fd *fd) {
   }
 }
 
-static int basic_pollset_maybe_work(grpc_pollset *pollset,
-                                    gpr_timespec deadline, gpr_timespec now,
-                                    int allow_synchronous_callback) {
+static void basic_pollset_maybe_work(grpc_pollset *pollset,
+                                     gpr_timespec deadline, gpr_timespec now,
+                                     int allow_synchronous_callback) {
   struct pollfd pfd[2];
   grpc_fd *fd;
   grpc_fd_watcher fd_watcher;
@@ -353,7 +352,7 @@ static int basic_pollset_maybe_work(grpc_pollset *pollset,
     /* Give do_promote priority so we don't starve it out */
     gpr_mu_unlock(&pollset->mu);
     gpr_mu_lock(&pollset->mu);
-    return 1;
+    return;
   }
   fd = pollset->data.ptr;
   if (fd && grpc_fd_is_orphaned(fd)) {
@@ -364,7 +363,7 @@ static int basic_pollset_maybe_work(grpc_pollset *pollset,
   kfd = grpc_pollset_kick_pre_poll(&pollset->kick_state);
   if (kfd == NULL) {
     /* Already kicked */
-    return 1;
+    return;
   }
   pfd[0].fd = GRPC_POLLSET_KICK_GET_FD(kfd);
   pfd[0].events = POLLIN;
@@ -418,7 +417,6 @@ static int basic_pollset_maybe_work(grpc_pollset *pollset,
 
   gpr_mu_lock(&pollset->mu);
   pollset->counter--;
-  return 1;
 }
 
 static void basic_pollset_destroy(grpc_pollset *pollset) {

src/core/iomgr/pollset_posix.h

@@ -68,8 +68,8 @@ typedef struct grpc_pollset {
 struct grpc_pollset_vtable {
   void (*add_fd)(grpc_pollset *pollset, struct grpc_fd *fd);
   void (*del_fd)(grpc_pollset *pollset, struct grpc_fd *fd);
-  int (*maybe_work)(grpc_pollset *pollset, gpr_timespec deadline,
-                    gpr_timespec now, int allow_synchronous_callback);
+  void (*maybe_work)(grpc_pollset *pollset, gpr_timespec deadline,
+                     gpr_timespec now, int allow_synchronous_callback);
   void (*kick)(grpc_pollset *pollset);
   void (*finish_shutdown)(grpc_pollset *pollset);
   void (*destroy)(grpc_pollset *pollset);