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Date: Tue, 19 Jun 2018 15:58:08 +0800
From: Wei Xu <wexu@redhat.com>
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Subject: Re: [Qemu-devel] [RFC v2 5/8] virtio: queue pop for packed ring
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To: Jason Wang <jasowang@redhat.com>
Cc: jfreimann@redhat.com, qemu-devel@nongnu.org, tiwei.bie@intel.com, mst@redhat.com

On Wed, Jun 06, 2018 at 11:41:18AM +0800, Jason Wang wrote:
>=20
>=20
> On 2018=E5=B9=B406=E6=9C=8806=E6=97=A5 11:38, Wei Xu wrote:
> >>>+
> >>>+    head =3D vq->last_avail_idx;
> >>>+    i =3D head;
> >>>+
> >>>+    caches =3D vring_get_region_caches(vq);
> >>>+    cache =3D &caches->desc;
> >>>+    vring_packed_desc_read(vdev, &desc, cache, i);
> >>I think we'd better find a way to avoid reading descriptor twice.
> >Do you mean here and the read for empty check?
> >
> >Wei
> >
>=20
> Yes.

OK, will figure it out.

>=20
> Thanks
>=20
>=20