Re: [PATCH net-next v3 2/8] taprio: Add support for frame preemption offload

Vladimir Oltean
2021-01-29T23:21:20Z

On Fri, Jan 29, 2021 at 01:13:24PM -0800, Vinicius Costa Gomes wrote:
> > Secondly, why should at least one queue be preemptible? What's wrong
> > with frame preemption being triggered by a tc-taprio window smaller than
> > the packet size? This can happen regardless of traffic class.
>
> It's the opposite, at least one queue needs to be marked
> express/non-preemptible.

I meant to ask why should at least one queue be express. The second part
of the question remains valid.

> But as I said above, perhaps this should be handled in a per-driver
> way. I will remove this from taprio.
>
> I think removing this check/limitation from taprio should solve the
> second part of your question, right?

Nope. Can you point me to either 802.1Q or 802.3 saying that at least
one priority should go to the express MAC?