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Date:   Wed, 21 Dec 2022 10:17:32 +0100
From:   Stefano Garzarella <sgarzare@redhat.com>
To:     Jason Wang <jasowang@redhat.com>
Cc:     mst@redhat.com, eperezma@redhat.com,
        virtualization@lists.linux-foundation.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] vdpa_sim: use weak barriers
Message-ID: <20221221091732.gvc724dnq2ntza7g@sgarzare-redhat>
References: <20221221062146.15356-1-jasowang@redhat.com>
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On Wed, Dec 21, 2022 at 02:21:46PM +0800, Jason Wang wrote:
>vDPA simulators are software emulated device, so let's switch to use
>weak barriers to avoid extra overhead in the driver.
>
>Signed-off-by: Jason Wang <jasowang@redhat.com>
>---
> drivers/vdpa/vdpa_sim/vdpa_sim.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)

I was going to propose the same :-)

Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>

>
>diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim.c b/drivers/vdpa/vdpa_sim/vdpa_sim.c
>index b071f0d842fb..eeaeaf43b476 100644
>--- a/drivers/vdpa/vdpa_sim/vdpa_sim.c
>+++ b/drivers/vdpa/vdpa_sim/vdpa_sim.c
>@@ -68,7 +68,7 @@ static void vdpasim_queue_ready(struct vdpasim *vdpasim, unsigned int idx)
> 	struct vdpasim_virtqueue *vq = &vdpasim->vqs[idx];
>
> 	vringh_init_iotlb(&vq->vring, vdpasim->dev_attr.supported_features,
>-			  VDPASIM_QUEUE_MAX, false,
>+			  VDPASIM_QUEUE_MAX, true,
> 			  (struct vring_desc *)(uintptr_t)vq->desc_addr,
> 			  (struct vring_avail *)
> 			  (uintptr_t)vq->driver_addr,
>-- 
>2.25.1
>