From 2af9e86a554433a249e37d93e5b384ecca5e2ca2 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Stefan=20B=C3=BChler?= <source@stbuehler.de>
Date: Wed, 24 Apr 2019 23:54:21 +0200
Subject: [PATCH 0469/2944] io_uring: remove unnecessary barrier after
 incrementing dropped counter
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commit b841f19524a16cd93a39f9306191f85c549a2bc2 upstream.

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: Joseph Qi <joseph.qi@linux.alibaba.com>
Reviewed-by: Jeffle Xu <jefflexu@linux.alibaba.com>
Acked-by: Caspar Zhang <caspar@linux.alibaba.com>
---
 fs/io_uring.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/fs/io_uring.c b/fs/io_uring.c
index 743adde..4f0f3f8 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -1846,8 +1846,6 @@ 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;
 }
 
-- 
1.8.3.1