Re: [PATCH net-next 2/4] gro: add combined call_gro_receive() + INDIRECT_CALL_INET() helper

[Alexander Lobakin]

From: Paolo Abeni <pabeni@xxxxxxxxxx>
Date: Fri, 19 Mar 2021 13:35:41 +0100

> On Fri, 2021-03-19 at 11:43 +0000, Alexander Lobakin wrote:
> > I'm not sure if you did it on purpose in commit aaa5d90b395a7
> > ("net: use indirect call wrappers at GRO network layer").
> > Was that intentional
>
> I must admit that 2y+ later my own intentions are not so clear to me
> too;)

Heh, know that feel (=

> > for the sake of more optimized path for the
> > kernels with moduled IPv6,
>
> Uhm... no I guess that was more an underlook on my side.
>
> > or I can replace INDIRECT_CALL_INET()
> > with INDIRECT_CALL_2() here too?
>
> If that build with IPV6=nmy, I would say yes.

I think you used INDIRECT_CALL_INET() to protect from CONFIG_INET=n.
But this also hurts with retpoline when CONFIG_IPV6=m. Not so common
case, but still.

Plain INDIRECT_CALL_2() won't build without CONFIG_INET, so we either
introduce a new one (e.g. _INET_2() similarly to _INET_1()), or leave
it as it is for now (Dave's already picked this series to net-next).

> > I want to keep GRO callbacks that
> > make use of indirect call wrappers unified.
>
> L4 will still need some special handling as ipv6 udp gro callbacks are
> not builtin with CONFIG_IPV6=m :(

Yep, I remember. I meant {inet,ipv6}_gro_{complete,receive}()
callers, but didn't mention that for some reason.

> Cheers,
>
> Paolo

Thanks,
Al