+ rte_smp_mb();
+
+ /* Don't kick guest if we don't reach index specified by guest. */
+ if (dev->features & (1ULL << VIRTIO_RING_F_EVENT_IDX)) {
+ uint16_t old = vq->signalled_used;
+ uint16_t new = vq->last_used_idx;
+ bool signalled_used_valid = vq->signalled_used_valid;
+
+ vq->signalled_used = new;
+ vq->signalled_used_valid = true;
+
+ VHOST_LOG_DATA(DEBUG, "%s: used_event_idx=%d, old=%d, new=%d\n",
+ __func__,
+ vhost_used_event(vq),
+ old, new);
+
+ if ((vhost_need_event(vhost_used_event(vq), new, old) &&
+ (vq->callfd >= 0)) ||
+ unlikely(!signalled_used_valid)) {
+ eventfd_write(vq->callfd, (eventfd_t) 1);
+ if (dev->notify_ops->guest_notified)
+ dev->notify_ops->guest_notified(dev->vid);
+ }
+ } else {
+ /* Kick the guest if necessary. */
+ if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT)
+ && (vq->callfd >= 0)) {
+ eventfd_write(vq->callfd, (eventfd_t)1);
+ if (dev->notify_ops->guest_notified)
+ dev->notify_ops->guest_notified(dev->vid);
+ }
+ }
+}
+
+static __rte_always_inline void
+vhost_vring_call_packed(struct virtio_net *dev, struct vhost_virtqueue *vq)
+{
+ uint16_t old, new, off, off_wrap;
+ bool signalled_used_valid, kick = false;
+
+ /* Flush used desc update. */
+ rte_smp_mb();
+
+ if (!(dev->features & (1ULL << VIRTIO_RING_F_EVENT_IDX))) {
+ if (vq->driver_event->flags !=
+ VRING_EVENT_F_DISABLE)
+ kick = true;
+ goto kick;
+ }
+
+ old = vq->signalled_used;
+ new = vq->last_used_idx;
+ vq->signalled_used = new;
+ signalled_used_valid = vq->signalled_used_valid;
+ vq->signalled_used_valid = true;