RE: [virtio-comment] Re: [PATCH 0/3] Rename queue index to queue number

[Parav Pandit <parav@nvidia.com>]

> From: Michael S. Tsirkin <mst@redhat.com>
> Sent: Wednesday, March 1, 2023 12:38 PM
> 
> On Wed, Mar 01, 2023 at 06:22:07PM +0100, Halil Pasic wrote:
> > On Mon, 27 Feb 2023 09:45:31 +0100
> > Cornelia Huck <cohuck@redhat.com> wrote:
> >
> > > For the vq index/number, I'm not that sure that "virtqueue number"
> > > is better that "virtqueue index" -- actually, I'd prefer the latter.
> > > We'd need some renaming either way.
> >
> > I prefer index as well. Especially that we start indexing with 0. Also
> > seems to be the more common term for such stuff in both Mathematics
> > and CS.
> >
> > Regards,
> > Halil
> 
> 
> Basically I am saying that this:
> 
> /* Queue size for the currently selected queue - Write Only */
> #define VIRTIO_MMIO_QUEUE_NUM           0x038
> 
> is a bad name because queue number seems to be ambiguous.
> 
> Maybe start with just getting rid of uses of QUEUE_NUM meaning size?
> 
> 
> If we want to use queue index we need to fix RSS spec in networking
> since that seems to want to use queue index in a very weird way:
> networking has this idea of calling queues like this:
> receiveq1 receiveq2 ....
> why 1-based? I guess we wanted this to be clear even to a 5 year olds ;)
> 
> And then for extra fun, in the RSS section we say "0 based index" where we
> seem to mean "this number in the queue name, but subtract 1 in your head".
> Why subtract 1? I guess we wanted these 5 year olds to practice math ...

:)

I think vqn is just fine that helps to keep things simple.

I will insert the patch to fix the net device's index text and other text suggestions that Michael had for MMIO side.