[PATCH] xen/netfront: remove unnecessary wmb

[PATCH] xen/netfront: remove unnecessary wmb

[Jacob Wen]

RING_PUSH_REQUESTS_AND_CHECK_NOTIFY is already able to make sure backend sees
requests before req_prod is updated.

Signed-off-by: Jacob Wen <jian.w.wen@oracle.com>
---
 drivers/net/xen-netfront.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c
index f17f602e6171..a8303afa15f1 100644
--- a/drivers/net/xen-netfront.c
+++ b/drivers/net/xen-netfront.c
@@ -337,8 +337,6 @@ static void xennet_alloc_rx_buffers(struct netfront_queue *queue)
 		return;
 	}
 
-	wmb();		/* barrier so backend seens requests */
-
 	RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(&queue->rx, notify);
 	if (notify)
 		notify_remote_via_irq(queue->rx_irq);
-- 
2.17.1

Re: [PATCH] xen/netfront: remove unnecessary wmb

[Juergen Gross]

On 09/11/2018 07:53, Jacob Wen wrote:
> RING_PUSH_REQUESTS_AND_CHECK_NOTIFY is already able to make sure backend sees
> requests before req_prod is updated.
> 
> Signed-off-by: Jacob Wen <jian.w.wen@oracle.com>

Reviewed-by: Juergen Gross <jgross@suse.com>


Juergen

Re: [Xen-devel] [PATCH] xen/netfront: remove unnecessary wmb

[Wei Liu]

On Fri, Nov 09, 2018 at 02:53:59PM +0800, Jacob Wen wrote:
> RING_PUSH_REQUESTS_AND_CHECK_NOTIFY is already able to make sure backend sees
> requests before req_prod is updated.
> 
> Signed-off-by: Jacob Wen <jian.w.wen@oracle.com>

Reviewed-by: Wei Liu <wei.liu2@citrix.com>

Re: [PATCH] xen/netfront: remove unnecessary wmb

[David Miller]

From: Jacob Wen <jian.w.wen@oracle.com>
Date: Fri,  9 Nov 2018 14:53:59 +0800

> RING_PUSH_REQUESTS_AND_CHECK_NOTIFY is already able to make sure backend sees
> requests before req_prod is updated.
> 
> Signed-off-by: Jacob Wen <jian.w.wen@oracle.com>

Applied to net-next.