Re: [Qemu-devel] [PATCH v3 12/12] virtio-scsi-dataplane: Add "device IO" op blocker listener

[Fam Zheng <famz@redhat.com>]

On Fri, 05/15 08:50, Paolo Bonzini wrote:
> 
> 
> On 15/05/2015 08:04, Fam Zheng wrote:
> > @@ -111,6 +111,10 @@ static void virtio_scsi_iothread_handle_ctrl(EventNotifier *notifier)
> >      VirtIOSCSI *s = VIRTIO_SCSI(vring->parent);
> >      VirtIOSCSIReq *req;
> >  
> > +    if (s->pause_counter) {
> > +        virtio_scsi_stop_ioeventfd(s);
> > +        return;
> > +    }
> >      event_notifier_test_and_clear(notifier);
> >      while ((req = virtio_scsi_pop_req_vring(s, vring))) {
> >          virtio_scsi_handle_ctrl_req(s, req);
> > @@ -124,6 +128,10 @@ static void virtio_scsi_iothread_handle_event(EventNotifier *notifier)
> >      VirtIOSCSI *s = vring->parent;
> >      VirtIODevice *vdev = VIRTIO_DEVICE(s);
> >  
> > +    if (s->pause_counter) {
> > +        virtio_scsi_stop_ioeventfd(s);
> > +        return;
> > +    }
> >      event_notifier_test_and_clear(notifier);
> >  
> >      if (!(vdev->status & VIRTIO_CONFIG_S_DRIVER_OK)) {
> 
> Why are these needed?

Not strictly. I think it's something like an "assert(!s->pause_counter)" but
said gently.

Fam