Message ID | 20201120185105.279030-11-eperezma@redhat.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Series | vDPA software assisted live migration | expand |
On Fri, Nov 20, 2020 at 07:50:48PM +0100, Eugenio Pérez wrote: > Signed-off-by: Eugenio Pérez <eperezma@redhat.com> > --- > hw/virtio/vhost-sw-lm-ring.c | 7 ++++++- > 1 file changed, 6 insertions(+), 1 deletion(-) > > diff --git a/hw/virtio/vhost-sw-lm-ring.c b/hw/virtio/vhost-sw-lm-ring.c > index cbf53965cd..cd7b5ba772 100644 > --- a/hw/virtio/vhost-sw-lm-ring.c > +++ b/hw/virtio/vhost-sw-lm-ring.c > @@ -16,8 +16,11 @@ > #include "qemu/event_notifier.h" > > typedef struct VhostShadowVirtqueue { > + struct vring vring; > EventNotifier hdev_notifier; > VirtQueue *vq; > + > + vring_desc_t descs[]; > } VhostShadowVirtqueue; VhostShadowVirtqueue is starting to look like VirtQueue. Can the shadow vq code simply use the VirtIODevice's VirtQueues instead of duplicating this? What I mean is: 1. Disable the vhost hdev vq and sync the avail index back to the VirtQueue. 2. Move the irq fd to the VirtQueue as its guest notifier. 3. Install the shadow_vq_handler() as the VirtQueue's handle_output function. 4. Move the call fd to the VirtQueue as its host notifier. Now we can process requests from the VirtIODevice's VirtQueue using virtqueue_pop() and friends. We're also in sync and ready for vmstate save/load.
On Fri, Nov 20, 2020 at 07:50:48PM +0100, Eugenio Pérez wrote: > Signed-off-by: Eugenio Pérez <eperezma@redhat.com> > --- > hw/virtio/vhost-sw-lm-ring.c | 7 ++++++- > 1 file changed, 6 insertions(+), 1 deletion(-) > > diff --git a/hw/virtio/vhost-sw-lm-ring.c b/hw/virtio/vhost-sw-lm-ring.c > index cbf53965cd..cd7b5ba772 100644 > --- a/hw/virtio/vhost-sw-lm-ring.c > +++ b/hw/virtio/vhost-sw-lm-ring.c > @@ -16,8 +16,11 @@ > #include "qemu/event_notifier.h" > > typedef struct VhostShadowVirtqueue { > + struct vring vring; > EventNotifier hdev_notifier; > VirtQueue *vq; > + > + vring_desc_t descs[]; > } VhostShadowVirtqueue; Looking at later patches I see that this is the vhost hdev vring state, not the VirtIODevice vring state. That makes more sense.
On Tue, Dec 8, 2020 at 9:18 AM Stefan Hajnoczi <stefanha@gmail.com> wrote: > > On Fri, Nov 20, 2020 at 07:50:48PM +0100, Eugenio Pérez wrote: > > Signed-off-by: Eugenio Pérez <eperezma@redhat.com> > > --- > > hw/virtio/vhost-sw-lm-ring.c | 7 ++++++- > > 1 file changed, 6 insertions(+), 1 deletion(-) > > > > diff --git a/hw/virtio/vhost-sw-lm-ring.c b/hw/virtio/vhost-sw-lm-ring.c > > index cbf53965cd..cd7b5ba772 100644 > > --- a/hw/virtio/vhost-sw-lm-ring.c > > +++ b/hw/virtio/vhost-sw-lm-ring.c > > @@ -16,8 +16,11 @@ > > #include "qemu/event_notifier.h" > > > > typedef struct VhostShadowVirtqueue { > > + struct vring vring; > > EventNotifier hdev_notifier; > > VirtQueue *vq; > > + > > + vring_desc_t descs[]; > > } VhostShadowVirtqueue; > > Looking at later patches I see that this is the vhost hdev vring state, > not the VirtIODevice vring state. That makes more sense. I will add a comment here too.
diff --git a/hw/virtio/vhost-sw-lm-ring.c b/hw/virtio/vhost-sw-lm-ring.c index cbf53965cd..cd7b5ba772 100644 --- a/hw/virtio/vhost-sw-lm-ring.c +++ b/hw/virtio/vhost-sw-lm-ring.c @@ -16,8 +16,11 @@ #include "qemu/event_notifier.h" typedef struct VhostShadowVirtqueue { + struct vring vring; EventNotifier hdev_notifier; VirtQueue *vq; + + vring_desc_t descs[]; } VhostShadowVirtqueue; static inline bool vhost_vring_should_kick(VhostShadowVirtqueue *vq) @@ -37,10 +40,12 @@ VhostShadowVirtqueue *vhost_sw_lm_shadow_vq(struct vhost_dev *dev, int idx) .index = idx }; VirtQueue *vq = virtio_get_queue(dev->vdev, idx); + unsigned num = virtio_queue_get_num(dev->vdev, idx); + size_t ring_size = vring_size(num, VRING_DESC_ALIGN_SIZE); VhostShadowVirtqueue *svq; int r; - svq = g_new0(VhostShadowVirtqueue, 1); + svq = g_malloc0(sizeof(*svq) + ring_size); svq->vq = vq; r = event_notifier_init(&svq->hdev_notifier, 0);
Signed-off-by: Eugenio Pérez <eperezma@redhat.com> --- hw/virtio/vhost-sw-lm-ring.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)