From: Paul E. McKenney Date: Mon, 27 Nov 2017 17:45:10 +0000 (-0800) Subject: drivers/vhost: Remove now-redundant read_barrier_depends() X-Git-Tag: v4.16-rc1~169^2^2^4 X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=3a5db0b108e0a40f08c2bcff6a675dbf632b91e0;p=linux.git drivers/vhost: Remove now-redundant read_barrier_depends() Because READ_ONCE() now implies read_barrier_depends(), the read_barrier_depends() in next_desc() is now redundant. This commit therefore removes it and the related comments. Signed-off-by: Paul E. McKenney Cc: "Michael S. Tsirkin" Cc: Jason Wang Cc: Cc: Cc: --- diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index 33ac2b186b85..78b5940a415a 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -1877,12 +1877,7 @@ static unsigned next_desc(struct vhost_virtqueue *vq, struct vring_desc *desc) return -1U; /* Check they're not leading us off end of descriptors. */ - next = vhost16_to_cpu(vq, desc->next); - /* Make sure compiler knows to grab that: we don't want it changing! */ - /* We will use the result as an index in an array, so most - * architectures only need a compiler barrier here. */ - read_barrier_depends(); - + next = vhost16_to_cpu(vq, READ_ONCE(desc->next)); return next; }