On Sat, Dec 27, 2025 at 3:57 AM Michael S. Tsirkin <[email protected]> wrote: > > On Thu, Dec 25, 2025 at 12:26:08PM +0800, Jason Wang wrote: > > This patch implements in order support for both split virtqueue and > > packed virtqueue. Performance could be gained for the device where the > > memory access could be expensive (e.g vhost-net or a real PCI device): > > > > Benchmark with KVM guest: > > > > Vhost-net on the host: (pktgen + XDP_DROP): > > > > in_order=off | in_order=on | +% > > TX: 4.51Mpps | 5.30Mpps | +17% > > RX: 3.47Mpps | 3.61Mpps | + 4% > > > > Vhost-user(testpmd) on the host: (pktgen/XDP_DROP): > > > > For split virtqueue: > > > > in_order=off | in_order=on | +% > > TX: 5.60Mpps | 5.60Mpps | +0.0% > > RX: 9.16Mpps | 9.61Mpps | +4.9% > > > > For packed virtqueue: > > > > in_order=off | in_order=on | +% > > TX: 5.60Mpps | 5.70Mpps | +1.7% > > RX: 10.6Mpps | 10.8Mpps | +1.8% > > > > Benchmark also shows no performance impact for in_order=off for queue > > size with 256 and 1024. > > > > Reviewed-by: Eugenio Pérez <[email protected]> > > Signed-off-by: Jason Wang <[email protected]> > > ---
[...] > > +unmap_release: > > + err_idx = i; > > + i = head; > > + vq->packed.avail_used_flags = avail_used_flags; > > Hmm. But this does not roll back packed.avail_wrap_counter. > Shouldn't it? Fixed. Thanks
