[Qemu-devel] [PATCH 5/8] virtio: notification tweak for packed ring

[wexu@redhat.com]

From: Wei Xu <wexu@redhat.com>

Always enable notify and bypass set notification
before supporting driver and device area.

Signed-off-by: Wei Xu <wexu@redhat.com>
---
 hw/virtio/virtio.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c
index fdee40f..95a4681 100644
--- a/hw/virtio/virtio.c
+++ b/hw/virtio/virtio.c
@@ -425,6 +425,10 @@ void virtio_queue_set_notification(VirtQueue *vq, int enable)
 {
     vq->notification = enable;
 
+    if (virtio_vdev_has_feature(vq->vdev, VIRTIO_F_RING_PACKED)) {
+        return;
+    }
+
     if (!vq->vring.desc) {
         return;
     }
@@ -1801,6 +1805,11 @@ static bool virtio_should_notify(VirtIODevice *vdev, VirtQueue *vq)
 {
     uint16_t old, new;
     bool v;
+
+    if (virtio_vdev_has_feature(vdev, VIRTIO_F_RING_PACKED)) {
+        return true;
+    }
+
     /* We need to expose used array entries before checking used event. */
     smp_mb();
     /* Always notify when queue is empty (when feature acknowledge) */
-- 
2.7.4