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References: <20221221062146.15356-1-jasowang@redhat.com>
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From:   Eugenio Perez Martin <eperezma@redhat.com>
Date:   Fri, 23 Dec 2022 11:11:00 +0100
Message-ID: <CAJaqyWcb6WniP33fb7UOQvxPN=i4LmBN2Jkmky2aCDs4RS6arw@mail.gmail.com>
Subject: Re: [PATCH] vdpa_sim: use weak barriers
To:     Jason Wang <jasowang@redhat.com>
Cc:     mst@redhat.com, sgarzare@redhat.com,
        virtualization@lists.linux-foundation.org,
        linux-kernel@vger.kernel.org
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On Wed, Dec 21, 2022 at 7:21 AM Jason Wang <jasowang@redhat.com> 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>

Acked-by: Eugenio P=C3=A9rez <eperezma@redhat.com>

Thanks!

> ---
>  drivers/vdpa/vdpa_sim/vdpa_sim.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim.c b/drivers/vdpa/vdpa_sim/vdp=
a_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 =3D &vdpasim->vqs[idx];
>
>         vringh_init_iotlb(&vq->vring, vdpasim->dev_attr.supported_feature=
s,
> -                         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
>