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stream: use harder sync restrictions for osx-hack

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Synchronize harder to avoid excessive spins, invokations of async
callback and sporadic assertion failures on double-call of async
callback.
This commit is contained in:
Fedor Indutny 2013-04-30 12:51:32 +04:00
parent 4e5b8dc2ef
commit 67f9b91a8b
1 changed files with 18 additions and 16 deletions
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34
src/unix/stream.c
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@ -46,8 +46,8 @@ typedef struct uv__stream_select_s uv__stream_select_t;
struct uv__stream_select_s {
uv_stream_t* stream;
uv_thread_t thread;
uv_sem_t sem;
uv_mutex_t mutex;
uv_sem_t close_sem;
uv_sem_t async_sem;
uv_async_t async;
int events;
int fake_fd;
@ -148,7 +148,7 @@ static void uv__stream_osx_select(void* arg) {
while (1) {
/* Terminate on semaphore */
if (uv_sem_trywait(&s->sem) == 0)
if (uv_sem_trywait(&s->close_sem) == 0)
break;
/* Watch fd using select(2) */
@ -204,11 +204,13 @@ static void uv__stream_osx_select(void* arg) {
assert(events != 0 || FD_ISSET(s->int_fd, &sread));
if (events != 0) {
uv_mutex_lock(&s->mutex);
s->events |= events;
ACCESS_ONCE(int, s->events) = events;
uv_async_send(&s->async);
uv_mutex_unlock(&s->mutex);
uv_sem_wait(&s->async_sem);
/* Should be processed at this stage */
assert((s->events == 0) || (stream->flags & UV_CLOSING));
}
}
}
@ -242,10 +244,9 @@ static void uv__stream_osx_select_cb(uv_async_t* handle, int status) {
stream = s->stream;
/* Get and reset stream's events */
uv_mutex_lock(&s->mutex);
events = s->events;
s->events = 0;
uv_mutex_unlock(&s->mutex);
ACCESS_ONCE(int, s->events) = 0;
uv_sem_post(&s->async_sem);
assert(events != 0);
assert(events == (events & (UV__POLLIN | UV__POLLOUT)));
@ -318,10 +319,10 @@ int uv__stream_try_select(uv_stream_t* stream, int* fd) {
s->async.flags |= UV__HANDLE_INTERNAL;
uv__handle_unref(&s->async);
if (uv_sem_init(&s->sem, 0))
if (uv_sem_init(&s->close_sem, 0))
goto fatal1;
if (uv_mutex_init(&s->mutex))
if (uv_sem_init(&s->async_sem, 0))
goto fatal2;
/* Create fds for io watcher and to interrupt the select() loop. */
@ -346,9 +347,9 @@ fatal4:
s->fake_fd = -1;
s->int_fd = -1;
fatal3:
uv_mutex_destroy(&s->mutex);
uv_sem_destroy(&s->async_sem);
fatal2:
uv_sem_destroy(&s->sem);
uv_sem_destroy(&s->close_sem);
fatal1:
uv_close((uv_handle_t*) &s->async, uv__stream_osx_cb_close);
return uv__set_sys_error(stream->loop, errno);
@ -1360,11 +1361,12 @@ void uv__stream_close(uv_stream_t* handle) {
s = handle->select;
uv_sem_post(&s->sem);
uv_sem_post(&s->close_sem);
uv_sem_post(&s->async_sem);
uv__stream_osx_interrupt_select(handle);
uv_thread_join(&s->thread);
uv_sem_destroy(&s->sem);
uv_mutex_destroy(&s->mutex);
uv_sem_destroy(&s->close_sem);
uv_sem_destroy(&s->async_sem);
close(s->fake_fd);
close(s->int_fd);
uv_close((uv_handle_t*) &s->async, uv__stream_osx_cb_close);