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Date: Mon, 11 Jan 2016 11:12:06 +0000
From: David Vrabel <david.vrabel@citrix.com>
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To: "Michael S. Tsirkin" <mst@redhat.com>, <linux-kernel@vger.kernel.org>
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Subject: Re: [PATCH v3 39/41] xen/events: use virt_xxx barriers
References: <1452426622-4471-1-git-send-email-mst@redhat.com>
 <1452426622-4471-40-git-send-email-mst@redhat.com>
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On 10/01/16 14:21, Michael S. Tsirkin wrote:
> drivers/xen/events/events_fifo.c uses rmb() to communicate with the
> other side.
> 
> For guests compiled with CONFIG_SMP, smp_rmb would be sufficient, so
> rmb() here is only needed if a non-SMP guest runs on an SMP host.
> 
> Switch to the virt_rmb barrier which serves this exact purpose.
> 
> Pull in asm/barrier.h here to make sure the file is self-contained.
> 
> Suggested-by: David Vrabel <david.vrabel@citrix.com>
> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

Acked-by: David Vrabel <david.vrabel@citrix.com>

David