RE: [virtio-dev] [PATCH v14 RESENT] virtio-net: support device stats

[Parav Pandit <parav@nvidia.com>]

> From: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
> Sent: Tuesday, August 15, 2023 9:09 AM

> On Mon, 7 Aug 2023 14:15:13 +0800, Xuan Zhuo
> <xuanzhuo@linux.alibaba.com> wrote:
> > On Mon, 31 Jul 2023 15:49:45 +0800, Xuan Zhuo
> <xuanzhuo@linux.alibaba.com> wrote:
> > > This patch allows the driver to obtain some statistics from the device.
> > >
> > > In the device implementation, we can count a lot of such
> > > information, which can be used for debugging and judging the running
> > > status of the device. We hope to directly display it to the user through
> ethtool.
> > >
> > > To get stats atomically, try to get stats for all queue pairs in one
> > > command.
> > >
> > > If the feature is negotiated, the device must support all the stats
> > > listed in this commit. If we want add new stats in future, one new
> > > feature should be introduced.
> >
All or nothing does not work as its very restrictive model.
Many stats can be cheaply counted (or already counted) by the driver today.
Hence it must be an extendible bitmap.

Finally supported bitmap to be queried via cvq of supported counters.

Didn't review every stat yet.