On Wed, Aug 02, 2023 at 11:56:11AM +0000, Parav Pandit wrote:
>
> > From: Michael S. Tsirkin <>
> > Sent: Wednesday, August 2, 2023 5:21 PM
>
> >
> > There's one thing to say about putting everything in one place, and that is that
> > one can then find everything in one place.
>
> When a device grows incrementally and each functionality also,
> grouping it per functionality gives better pace to keep things self-contained.
>
> Think how messy a set command would be if all 3 functionality in one set command.
>
> > For example, at the moment we actually do have a problem with cvq, and the
> > problem is that it sets internal device state that is not observable (unlike original
> > pre-1.0 config space which was writeable).
> >
> Which part is not observable?
e.g. rss config.
> >
> > By the way there's a pci express ECN for relaxed ordering or something like this.
> > I am yet to look at it, I wonder whether it can be used to avoid the issues we
> > have with MMIO in a way that is easier to use than DMA.
>
> Waiting to deliver new features on new PCI standard will drastically slow down virtio.
features? surely not. but when we are building a new transport then
we are building for the future, it takes years for a new
transport to be deployed.
> I don't think its good idea, but I would like to know about such ECN, if there is one.
I am talking about unordered IO (UIO) ECN.