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From:   Jason Wang <jasowang@redhat.com>
Date:   Fri, 17 Jun 2022 09:15:19 +0800
Message-ID: <CACGkMEtytpnCdWdmSh-BuFGXt55DJ9dYxnbw7JQwMXi9bQ8fvQ@mail.gmail.com>
Subject: Re: [PATCH v4 0/4] Implement vdpasim stop operation
To:     Parav Pandit <parav@nvidia.com>
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On Fri, Jun 17, 2022 at 3:36 AM Parav Pandit <parav@nvidia.com> wrote:
>
>
> > From: Jason Wang <jasowang@redhat.com>
> > Sent: Tuesday, June 14, 2022 9:29 PM
> >
> > Well, it's an example of how vDPA is implemented. I think we agree that=
 for
> > vDPA, vendors have the flexibility to implement their perferrable datap=
ath.
> >
> Yes for the vdpa level and for the virtio level.
>
> > >
> > > I remember few months back, you acked in the weekly meeting that TC h=
as
> > approved the AQ direction.
> > > And we are still in this circle of debating the AQ.
> >
> > I think not. Just to make sure we are on the same page, the proposal he=
re is
> > for vDPA, and hope it can provide forward compatibility to virtio. So i=
n the
> > context of vDPA, admin virtqueue is not a must.
> In context of vdpa over virtio, an efficient transport interface is neede=
d.
> If AQ is not much any other interface such as hundreds to thousands of re=
gisters is not must either.
>
> AQ is one interface proposed with multiple benefits.
> I haven=E2=80=99t seen any other alternatives that delivers all the benef=
its.
> Only one I have seen is synchronous config registers.
>
> If you let vendors progress, handful of sensible interfaces can exist, ea=
ch with different characteristics.
> How would we proceed from here?

I'm pretty fine with having admin virtqueue in the virtio spec. If you
remember, I've even submitted a proposal to use admin virtqueue as a
transport last year.

Let's just proceed in the virtio-dev list.

Thanks