On Mon, Jun 18, 2012 at 7:53 AM, Asias He <asias@xxxxxxxxxx> wrote: > +static void virtblk_add_buf_wait(struct virtio_blk *vblk, > + struct virtblk_req *vbr, > + unsigned long out, > + unsigned long in) > +{ > + DEFINE_WAIT(wait); > + > + for (;;) { > + prepare_to_wait_exclusive(&vblk->queue_wait, &wait, > + TASK_UNINTERRUPTIBLE); > + > + spin_lock_irq(vblk->disk->queue->queue_lock); > + if (virtqueue_add_buf(vblk->vq, vbr->sg, out, in, vbr, > + GFP_ATOMIC) < 0) { > + spin_unlock_irq(vblk->disk->queue->queue_lock); > + io_schedule(); > + } else { > + virtqueue_kick(vblk->vq); > + spin_unlock_irq(vblk->disk->queue->queue_lock); > + break; > + } > + > + } Is there a meaningful condition where we would cancel this request (e.g. signal)? If the vring fills up for some reason and we get stuck here the user might wish to kill hung processes. Stefan -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html