From 51097e80f6e91cb9c714bcf236176b5e6d07df70 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Stefan=20B=C3=BChler?= Date: Wed, 24 Apr 2019 23:54:22 +0200 Subject: [PATCH 0470/2944] io_uring: remove unnecessary barrier after unsetting IORING_SQ_NEED_WAKEUP MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit commit 62977281a6384d3904c02272a638cc3ac3bac54d upstream. There is no operation to order with afterwards, and removing the flag is not critical in any way. There will always be a "race condition" where the application will trigger IORING_ENTER_SQ_WAKEUP when it isn't actually needed. Signed-off-by: Stefan Bühler Signed-off-by: Jens Axboe Signed-off-by: Joseph Qi Reviewed-by: Jeffle Xu Acked-by: Caspar Zhang --- fs/io_uring.c | 2 -- 1 file changed, 2 deletions(-) diff --git a/fs/io_uring.c b/fs/io_uring.c index 4f0f3f8..a94444a 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -1969,13 +1969,11 @@ static int io_sq_thread(void *data) finish_wait(&ctx->sqo_wait, &wait); ctx->sq_ring->flags &= ~IORING_SQ_NEED_WAKEUP; - smp_wmb(); continue; } finish_wait(&ctx->sqo_wait, &wait); ctx->sq_ring->flags &= ~IORING_SQ_NEED_WAKEUP; - smp_wmb(); } i = 0; -- 1.8.3.1