diff --git a/util/aio-posix.c b/util/aio-posix.c index b339aab12c..65964a2597 100644 --- a/util/aio-posix.c +++ b/util/aio-posix.c @@ -361,12 +361,13 @@ void aio_set_event_notifier_poll(AioContext *ctx, (IOHandler *)io_poll_end); } -static void poll_set_started(AioContext *ctx, bool started) +static bool poll_set_started(AioContext *ctx, bool started) { AioHandler *node; + bool progress = false; if (started == ctx->poll_started) { - return; + return false; } ctx->poll_started = started; @@ -388,8 +389,15 @@ static void poll_set_started(AioContext *ctx, bool started) if (fn) { fn(node->opaque); } + + /* Poll one last time in case ->io_poll_end() raced with the event */ + if (!started) { + progress = node->io_poll(node->opaque) || progress; + } } qemu_lockcnt_dec(&ctx->list_lock); + + return progress; } @@ -670,12 +678,12 @@ static bool try_poll_mode(AioContext *ctx, int64_t *timeout) } } - poll_set_started(ctx, false); + if (poll_set_started(ctx, false)) { + *timeout = 0; + return true; + } - /* Even if we don't run busy polling, try polling once in case it can make - * progress and the caller will be able to avoid ppoll(2)/epoll_wait(2). - */ - return run_poll_handlers_once(ctx, timeout); + return false; } bool aio_poll(AioContext *ctx, bool blocking)