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Date:   Fri, 19 Mar 2021 11:43:09 +0000
To:     Paolo Abeni <pabeni@redhat.com>
From:   Alexander Lobakin <alobakin@pm.me>
Cc:     Alexander Lobakin <alobakin@pm.me>,
        "David S. Miller" <davem@davemloft.net>,
        Jakub Kicinski <kuba@kernel.org>,
        Mauro Carvalho Chehab <mchehab+huawei@kernel.org>,
        Kirill Tkhai <ktkhai@virtuozzo.com>,
        Bartosz Golaszewski <bgolaszewski@baylibre.com>,
        Leon Romanovsky <leon@kernel.org>,
        Eric Dumazet <edumazet@google.com>, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org
Reply-To: Alexander Lobakin <alobakin@pm.me>
Subject: Re: [PATCH net-next 2/4] gro: add combined call_gro_receive() + INDIRECT_CALL_INET() helper
Message-ID: <20210319114300.108808-1-alobakin@pm.me>
In-Reply-To: <20210319111315.3069-1-alobakin@pm.me>
References: <20210318184157.700604-1-alobakin@pm.me> <20210318184157.700604-3-alobakin@pm.me> <1ebd301832ff86cc414dd17eee0b3dfc91ff3c08.camel@redhat.com> <20210319111315.3069-1-alobakin@pm.me>
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From: Alexander Lobakin <alobakin@pm.me>
Date: Fri, 19 Mar 2021 11:13:25 +0000

> From: Paolo Abeni <pabeni@redhat.com>
> Date: Fri, 19 Mar 2021 11:53:42 +0100
>
> > Hello,
>
> Hi!
>
> > On Thu, 2021-03-18 at 18:42 +0000, Alexander Lobakin wrote:
> > > call_gro_receive() is used to limit GRO recursion, but it works only
> > > with callback pointers.
> > > There's a combined version of call_gro_receive() + INDIRECT_CALL_2()
> > > in <net/inet_common.h>, but it doesn't check for IPv6 modularity.
> >
> > AFAICS, ip6_offload is builtin even when IPv6 is a module, so the above
> > should not be needed.
>
> Aww, you are right. I overlooked that since dev_gro_receive() still
> use INDIRECT_CALL_INET(), though all GRO callbacks were made
> built-in.

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 for the sake of more optimized path for the
kernels with moduled IPv6, or I can replace INDIRECT_CALL_INET()
with INDIRECT_CALL_2() here too? I want to keep GRO callbacks that
make use of indirect call wrappers unified.

> Seems like more code can be optimized, thanks!
>
> > Cheers,
> >
> > Paolo
>
> Al

Thanks,
Al