Re: [PATCH V8 0/6] mdev based hardware virtio offloading support

Alex Williamson
2019-11-06T21:13:48Z

On Wed, 6 Nov 2019 14:25:23 -0500
"Michael S. Tsirkin" <mst@redhat.com> wrote:

> On Wed, Nov 06, 2019 at 12:03:12PM -0700, Alex Williamson wrote:
> > On Wed, 6 Nov 2019 11:56:46 +0800
> > Jason Wang <jasowang@redhat.com> wrote:
> >
> > > On 2019/11/6 上午1:58, Alex Williamson wrote:
> > > > On Tue, 5 Nov 2019 17:32:34 +0800
> > > > Jason Wang <jasowang@redhat.com> wrote:
> > > >
> > > >> Hi all:
> > > >>
> > > >> There are hardwares that can do virtio datapath offloading while
> > > >> having its own control path. This path tries to implement a mdev based
> > > >> unified API to support using kernel virtio driver to drive those
> > > >> devices. This is done by introducing a new mdev transport for virtio
> > > >> (virtio_mdev) and register itself as a new kind of mdev driver. Then
> > > >> it provides a unified way for kernel virtio driver to talk with mdev
> > > >> device implementation.
> > > >>
> > > >> Though the series only contains kernel driver support, the goal is to
> > > >> make the transport generic enough to support userspace drivers. This
> > > >> means vhost-mdev[1] could be built on top as well by resuing the
> > > >> transport.
> > > >>
> > > >> A sample driver is also implemented which simulate a virito-net
> > > >> loopback ethernet device on top of vringh + workqueue. This could be
> > > >> used as a reference implementation for real hardware driver.
> > > >>
> > > >> Also a real ICF VF driver was also posted here[2] which is a good
> > > >> reference for vendors who is interested in their own virtio datapath
> > > >> offloading product.
> > > >>
> > > >> Consider mdev framework only support VFIO device and driver right now,
> > > >> this series also extend it to support other types. This is done
> > > >> through introducing class id to the device and pairing it with
> > > >> id_talbe claimed by the driver. On top, this seris also decouple
> > > >> device specific parents ops out of the common ones.
> > > >>
> > > >> Pktgen test was done with virito-net + mvnet loop back device.
> > > >>
> > > >> Please review.
> > > >>
> > > >> [1] https://lkml.org/lkml/2019/10/31/440
> > > >> [2] https://lkml.org/lkml/2019/10/15/1226
> > > >>
> > > >> Changes from V7:
> > > >> - drop {set|get}_mdev_features for virtio
> > > >> - typo and comment style fixes
> > > >
> > > > Seems we're nearly there, all the remaining comments are relatively
> > > > superficial, though I would appreciate a v9 addressing them as well as
> > > > the checkpatch warnings:
> > > >
> > > > https://patchwork.freedesktop.org/series/68977/
> > >
> > >
> > > Will do.
> > >
> > > Btw, do you plan to merge vhost-mdev patch on top? Or you prefer it to
> > > go through Michael's vhost tree?
> >
> > I can include it if you wish. The mdev changes are isolated enough in
> > that patch that I wouldn't presume it, but clearly it would require
> > less merge coordination to drop it in my tree. Let me know. Thanks,
> >
> > Alex
>
> I'm fine with merging through your tree. If you do, feel free to
> include
>
> Acked-by: Michael S. Tsirkin <mst@redhat.com>

AFAICT, it looks like we're expecting at least one more version of
Tiwei's patch after V5, so it'd probably be best to provide the ack and
go-ahead on that next version so there's no confusion. Thanks,

Alex