On 08/05/13 10:18, Gal Hammer wrote:
> Signed-off-by: Gal Hammer <gham...@redhat.com>
> ---
> hw/char/virtio-serial-bus.c | 6 +++++-
> 1 file changed, 5 insertions(+), 1 deletion(-)
>
> diff --git a/hw/char/virtio-serial-bus.c b/hw/char/virtio-serial-bus.c
> index da417c7..0d38b4b 100644
> --- a/hw/char/virtio-serial-bus.c
> +++ b/hw/char/virtio-serial-bus.c
> @@ -105,6 +105,7 @@ static void do_flush_queued_data(VirtIOSerialPort *port,
> VirtQueue *vq,
> VirtIODevice *vdev)
> {
> VirtIOSerialPortClass *vsc;
> + bool elem_pushed = false;
>
> assert(port);
> assert(virtio_queue_ready(vq));
> @@ -145,9 +146,12 @@ static void do_flush_queued_data(VirtIOSerialPort *port,
> VirtQueue *vq,
> break;
> }
> virtqueue_push(vq, &port->elem, 0);
> + elem_pushed = true;
> port->elem.out_num = 0;
> }
> - virtio_notify(vdev, vq);
> + if (elem_pushed) {
> + virtio_notify(vdev, vq);
> + }
> }
>
> static void flush_queued_data(VirtIOSerialPort *port)
>
I could be missing something, but it looks good to me.
BTW the subject should say: "virtio-serial: ...", not generic "virtio: ...".
How did you catch this? Is this a performance problem, or did it expose
a guest driver bug? (The guest driver should be prepared for spurious
wakeups.)
Reviewed-by: Laszlo Ersek <ler...@redhat.com>
