@@ -2053,6 +2053,13 @@ static void virtio_queue_host_notifier_aio_read(EventNotifier *n)
}
}
+static void virtio_queue_host_notifier_aio_poll_begin(EventNotifier *n)
+{
+ VirtQueue *vq = container_of(n, VirtQueue, host_notifier);
+
+ virtio_queue_set_notification(vq, 0);
+}
+
static bool virtio_queue_host_notifier_aio_poll(void *opaque)
{
EventNotifier *n = opaque;
@@ -2066,6 +2073,14 @@ static bool virtio_queue_host_notifier_aio_poll(void *opaque)
return true;
}
+static void virtio_queue_host_notifier_aio_poll_end(EventNotifier *n)
+{
+ VirtQueue *vq = container_of(n, VirtQueue, host_notifier);
+
+ /* Caller polls once more after this to catch requests that race with us */
+ virtio_queue_set_notification(vq, 1);
+}
+
void virtio_queue_aio_set_host_notifier_handler(VirtQueue *vq, AioContext *ctx,
VirtIOHandleOutput handle_output)
{
@@ -2074,6 +2089,9 @@ void virtio_queue_aio_set_host_notifier_handler(VirtQueue *vq, AioContext *ctx,
aio_set_event_notifier(ctx, &vq->host_notifier, true,
virtio_queue_host_notifier_aio_read,
virtio_queue_host_notifier_aio_poll);
+ aio_set_event_notifier_poll(ctx, &vq->host_notifier,
+ virtio_queue_host_notifier_aio_poll_begin,
+ virtio_queue_host_notifier_aio_poll_end);
} else {
aio_set_event_notifier(ctx, &vq->host_notifier, true, NULL, NULL);
/* Test and clear notifier before after disabling event,
This is a performance optimization to eliminate vmexits during polling. It also avoids spurious ioeventfd processing after polling ends. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> --- hw/virtio/virtio.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+)