RE: [PATCH v4 0/4] Implement vdpasim stop operation

From: Parav Pandit
Date: Thu Jun 16 2022 - 22:42:35 EST




> From: Jason Wang <jasowang@xxxxxxxxxx>
> Sent: Thursday, June 16, 2022 9:15 PM
>
> On Fri, Jun 17, 2022 at 3:36 AM Parav Pandit <parav@xxxxxxxxxx> wrote:
> >
> >
> > > From: Jason Wang <jasowang@xxxxxxxxxx>
> > > 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
> datapath.
> > >
> > Yes for the vdpa level and for the virtio level.
> >
> > > >
> > > > I remember few months back, you acked in the weekly meeting that
> > > > TC has
> > > 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
> > > here is for vDPA, and hope it can provide forward compatibility to
> > > virtio. So in the context of vDPA, admin virtqueue is not a must.
> > In context of vdpa over virtio, an efficient transport interface is needed.
> > If AQ is not much any other interface such as hundreds to thousands of
> registers is not must either.
> >
> > AQ is one interface proposed with multiple benefits.
> > I haven’t seen any other alternatives that delivers all the benefits.
> > Only one I have seen is synchronous config registers.
> >
> > If you let vendors progress, handful of sensible interfaces can exist, each
> 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.

o.k. thanks. I am aligned with your thoughts now.