Re: [Qemu-devel] [PATCH] virtio: Register host notifier handler as external

["Michael S. Tsirkin" <mst@redhat.com>]

On Thu, Apr 21, 2016 at 10:04:28AM +0800, Fam Zheng wrote:
> This ensures the bdrv_drained_begin() in block layer is effective and
> fixes launchpad bug #1570134.
> 
> Signed-off-by: Fam Zheng <famz@redhat.com>
> ---
>  hw/virtio/virtio.c | 7 ++++---
>  1 file changed, 4 insertions(+), 3 deletions(-)
> 
> diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c
> index f745c4a..002c2c6 100644
> --- a/hw/virtio/virtio.c
> +++ b/hw/virtio/virtio.c
> @@ -1829,10 +1829,11 @@ void virtio_queue_set_host_notifier_fd_handler(VirtQueue *vq, bool assign,
>                                                 bool set_handler)
>  {
>      if (assign && set_handler) {
> -        event_notifier_set_handler(&vq->host_notifier,
> -                                   virtio_queue_host_notifier_read);
> +        aio_set_event_notifier(qemu_get_aio_context(), &vq->host_notifier,
> +                               true, virtio_queue_host_notifier_read);
>      } else {
> -        event_notifier_set_handler(&vq->host_notifier, NULL);
> +        aio_set_event_notifier(qemu_get_aio_context(), &vq->host_notifier,
> +                               true, NULL);
>      }
>      if (!assign) {
>          /* Test and clear notifier before after disabling event,

Is this the right thing to do in all cases?
E.g. it doesn't look like event_notifier_set_handler previously called
aio_set_event_notifier on win32. Was there a reason for this?


> -- 
> 2.8.0