Re: [RFC v5 0/5] virtio: support packed ring

From: Tiwei Bie
Date: Fri May 25 2018 - 07:59:20 EST


On Fri, May 25, 2018 at 10:31:26AM +0800, Jason Wang wrote:
> On 2018å05æ22æ 16:16, Tiwei Bie wrote:
> > Hello everyone,
> >
> > This RFC implements packed ring support in virtio driver.
> >
> > Some simple functional tests have been done with Jason's
> > packed ring implementation in vhost (RFC v4):
> >
> > https://lkml.org/lkml/2018/5/16/501
> >
> > Both of ping and netperf worked as expected w/ EVENT_IDX
> > disabled. Ping worked as expected w/ EVENT_IDX enabled,
> > but netperf didn't (A hack has been added in the driver
> > to make netperf test pass in this case. The hack can be
> > found by `grep -rw XXX` in the code).
>
> Looks like this is because a bug in vhost which wrongly track signalled_used
> and may miss an interrupt. After fixing that, both side works like a charm.
>
> I'm testing vIOMMU and zerocopy, and will post a new version shortly. (Hope
> it would be the last RFC version).

Great to know that. Thanks a lot! :)

Best regards,
Tiwei Bie