On Wed, Jan 24, 2018 at 01:47:47PM +0800, Wei Wang wrote: > On 01/24/2018 01:01 PM, Michael S. Tsirkin wrote: > > On Wed, Jan 24, 2018 at 10:50:27AM +0800, Wei Wang wrote: > > This will not DTRT in all cases. It's quite possible > > that host does not need the kick when ring is half full but > > does need it later when ring is full. > > You can kick at ring half full as optimization but you absolutely > > still must kick on ring full. Something like: > > > > if (vq->num_free == virtqueue_get_vring_size(vq) / 2 || > > vq->num_free <= 2) > > Right. Would "if (vq->num_free < virtqueue_get_vring_size(vq) / 2" be > better? > > > Best, > Wei It gives more kicks ... this reminds me, you need to validate that vring size is at least 2, otherwise fail probe. -- MST
