From 93ee4a5af8633370476f83a51f0e63349097005d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Stefan=20B=C3=BChler?= <source@stbuehler.de>
Date: Thu, 15 Apr 2021 17:30:59 +0800
Subject: [PATCH] io_uring: remove unnecessary barrier after incrementing
 dropped counter
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

mainline inclusion
from mainline-5.1
commit b841f19524a16cd93a39f9306191f85c549a2bc2
category: feature
bugzilla: https://bugzilla.openeuler.org/show_bug.cgi?id=27
CVE: NA
---------------------------

smp_store_release in io_commit_sqring already orders the store to
dropped before the update to SQ head.

Signed-off-by: Stefan Bühler <source@stbuehler.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: yangerkun <yangerkun@huawei.com>
Reviewed-by: zhangyi (F) <yi.zhang@huawei.com>
Signed-off-by: Cheng Jian <cj.chengjian@huawei.com>
---
 fs/io_uring.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/fs/io_uring.c b/fs/io_uring.c
index ba3fb2d8ec27..0a0fbb236147 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -1843,8 +1843,6 @@ static bool io_get_sqring(struct io_ring_ctx *ctx, struct sqe_submit *s)
 	/* drop invalid entries */
 	ctx->cached_sq_head++;
 	ring->dropped++;
-	/* See comment at the top of this file */
-	smp_wmb();
 	return false;
 }
 
-- 
GitLab