Subject: Re: [RFC bpf-next v2 06/11] net: veth: Implement devtx timestamp kfuncs

From: Vinicius Costa Gomes <[email-masked]>
Date: Fri, 23 Jun 2023 16:29:29 -0700

Stanislav Fomichev <[email-masked]> writes:

> Have a software-based example for kfuncs to showcase how it
> can be used in the real devices and to have something to
> test against in the selftests.
>
> Both path (skb & xdp) are covered. Only the skb path is really
> tested though.
>
> Cc: [email-masked]
> Signed-off-by: Stanislav Fomichev <[email-masked]>

Not really related to this patch, but to how it would work with
different drivers/hardware.

In some of our hardware (the ones handled by igc/igb, for example), the
timestamp notification comes some time after the transmit completion
event.

>From what I could gather, the idea would be for the driver to "hold" the
completion until the timestamp is ready and then signal the completion
of the frame. Is that right?

Cheers,
-- 
Vinicius