From: SF Markus Elfring <elfring@users.sourceforge.net>
Date: Sun, 15 Nov 2015 06:17:46 +0000
Subject: Re: net-ipv6: Delete unnecessary checks before the function call "kfree_skb"
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List-Id: <kernel-janitors.vger.kernel.org>
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To: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>, "David S. Miller" <davem@davemloft.net>, Hideaki Yoshfuji <yoshfuji@linux-ipv6.org>, James Morris <jmorris@namei.org>, Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>, Pablo Neira Ayuso <pablo@netfilter.org>, Patrick McHardy <kaber@trash.net>, netdev@vger.kernel.org, netfilter-devel@vger.kernel.org, coreteam@netfilter.org, LKML <linux-kernel@vger.kernel.org>, kernel-janitors@vger.kernel.org, Julia Lawall <julia.lawall@lip6.fr>

> While if the test is done in kfree_skb(), the branch predictor of the
> cpu wont be able to predict things.
> 
> By feeding too many NULL pointers to kfree_skb(), we slow down it.

Would it make sense to annotate checks before such function calls
as "UNLIKELY"?

Regards,
Markus