Virtualization - Jun 2022 - [PATCH v4 0/4] Implement vdpasim stop operation

> From: Jason Wang <jasowang at 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 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?

On Fri, Jun 17, 2022 at 3:36 AM Parav Pandit <parav at nvidia.com>
wrote:
>
>
> > From: Jason Wang <jasowang at 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
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.

Thanks