| Message ID | 20230224155438.112797-9-eperezma@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Dynamically switch to vhost shadow virtqueues at vdpa net migration | expand |
在 2023/2/24 23:54, Eugenio Pérez 写道: > At this moment it is only possible to migrate to a vdpa device running > with x-svq=on. As a protective measure, the rewind of the inflight > descriptors was done at the destination. That way if the source sent a > virtqueue with inuse descriptors they are always discarded. > > Since this series allows to migrate also to passthrough devices with no > SVQ, the right thing to do is to rewind at the source so the base of > vrings are correct. > > Support for inflight descriptors may be added in the future. > > Signed-off-by: Eugenio Pérez <eperezma@redhat.com> Acked-by: Jason Wang <jasowang@redhat.com> Thanks > --- > v4: > * Use virtqueue_unpop at vhost_svq_stop instead of rewinding at > vhost_vdpa_get_vring_base. > --- > hw/virtio/vhost-shadow-virtqueue.c | 8 ++++++-- > hw/virtio/vhost-vdpa.c | 11 ----------- > 2 files changed, 6 insertions(+), 13 deletions(-) > > diff --git a/hw/virtio/vhost-shadow-virtqueue.c b/hw/virtio/vhost-shadow-virtqueue.c > index 4307296358..523b379439 100644 > --- a/hw/virtio/vhost-shadow-virtqueue.c > +++ b/hw/virtio/vhost-shadow-virtqueue.c > @@ -694,13 +694,17 @@ void vhost_svq_stop(VhostShadowVirtqueue *svq) > g_autofree VirtQueueElement *elem = NULL; > elem = g_steal_pointer(&svq->desc_state[i].elem); > if (elem) { > - virtqueue_detach_element(svq->vq, elem, 0); > + /* > + * TODO: This is ok for networking, but other kinds of devices > + * might have problems with just unpop these. > + */ > + virtqueue_unpop(svq->vq, elem, 0); > } > } > > next_avail_elem = g_steal_pointer(&svq->next_guest_avail_elem); > if (next_avail_elem) { > - virtqueue_detach_element(svq->vq, next_avail_elem, 0); > + virtqueue_unpop(svq->vq, next_avail_elem, 0); > } > svq->vq = NULL; > g_free(svq->desc_next); > diff --git a/hw/virtio/vhost-vdpa.c b/hw/virtio/vhost-vdpa.c > index f542960a64..71e3dc21fe 100644 > --- a/hw/virtio/vhost-vdpa.c > +++ b/hw/virtio/vhost-vdpa.c > @@ -1218,18 +1218,7 @@ static int vhost_vdpa_set_vring_base(struct vhost_dev *dev, > struct vhost_vring_state *ring) > { > struct vhost_vdpa *v = dev->opaque; > - VirtQueue *vq = virtio_get_queue(dev->vdev, ring->index); > > - /* > - * vhost-vdpa devices does not support in-flight requests. Set all of them > - * as available. > - * > - * TODO: This is ok for networking, but other kinds of devices might > - * have problems with these retransmissions. > - */ > - while (virtqueue_rewind(vq, 1)) { > - continue; > - } > if (v->shadow_vqs_enabled) { > /* > * Device vring base was set at device start. SVQ base is handled by
diff --git a/hw/virtio/vhost-shadow-virtqueue.c b/hw/virtio/vhost-shadow-virtqueue.c index 4307296358..523b379439 100644 --- a/hw/virtio/vhost-shadow-virtqueue.c +++ b/hw/virtio/vhost-shadow-virtqueue.c @@ -694,13 +694,17 @@ void vhost_svq_stop(VhostShadowVirtqueue *svq) g_autofree VirtQueueElement *elem = NULL; elem = g_steal_pointer(&svq->desc_state[i].elem); if (elem) { - virtqueue_detach_element(svq->vq, elem, 0); + /* + * TODO: This is ok for networking, but other kinds of devices + * might have problems with just unpop these. + */ + virtqueue_unpop(svq->vq, elem, 0); } } next_avail_elem = g_steal_pointer(&svq->next_guest_avail_elem); if (next_avail_elem) { - virtqueue_detach_element(svq->vq, next_avail_elem, 0); + virtqueue_unpop(svq->vq, next_avail_elem, 0); } svq->vq = NULL; g_free(svq->desc_next); diff --git a/hw/virtio/vhost-vdpa.c b/hw/virtio/vhost-vdpa.c index f542960a64..71e3dc21fe 100644 --- a/hw/virtio/vhost-vdpa.c +++ b/hw/virtio/vhost-vdpa.c @@ -1218,18 +1218,7 @@ static int vhost_vdpa_set_vring_base(struct vhost_dev *dev, struct vhost_vring_state *ring) { struct vhost_vdpa *v = dev->opaque; - VirtQueue *vq = virtio_get_queue(dev->vdev, ring->index); - /* - * vhost-vdpa devices does not support in-flight requests. Set all of them - * as available. - * - * TODO: This is ok for networking, but other kinds of devices might - * have problems with these retransmissions. - */ - while (virtqueue_rewind(vq, 1)) { - continue; - } if (v->shadow_vqs_enabled) { /* * Device vring base was set at device start. SVQ base is handled by
At this moment it is only possible to migrate to a vdpa device running with x-svq=on. As a protective measure, the rewind of the inflight descriptors was done at the destination. That way if the source sent a virtqueue with inuse descriptors they are always discarded. Since this series allows to migrate also to passthrough devices with no SVQ, the right thing to do is to rewind at the source so the base of vrings are correct. Support for inflight descriptors may be added in the future. Signed-off-by: Eugenio Pérez <eperezma@redhat.com> --- v4: * Use virtqueue_unpop at vhost_svq_stop instead of rewinding at vhost_vdpa_get_vring_base. --- hw/virtio/vhost-shadow-virtqueue.c | 8 ++++++-- hw/virtio/vhost-vdpa.c | 11 ----------- 2 files changed, 6 insertions(+), 13 deletions(-)