On (Thu) 29 Dec 2011 [15:16:55], Christian Borntraeger wrote:
> >> +++ b/hw/virtio-serial-bus.c
> >> @@ -163,7 +163,19 @@ static void do_flush_queued_data(VirtIOS
> >> abort();
> >> }
> >> if (ret == -EAGAIN || (ret >= 0 && ret < buf_size)) {
> >> - virtio_serial_throttle_port(port, true);
> >
> > I'm surprised: did you test this with upstream qemu? That codebase
> > doesn't yet throttle writes, and this code path won't execute. Does
> > it really not reproduce with this patch?
>
> I think
> static void handle_output(VirtIODevice *vdev, VirtQueue *vq)
> [....]
> if (!port->throttled) {
> do_flush_queued_data(port, vq, vdev);
> return;
>
> makes a difference here, since we will never return the buffer to the guest,
> no?
port->throttled never becomes true for qemu. I'm just unsure how this
patch works for you :)
Amit
