From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Fri, 18 Nov 2011 17:32:46 +0000 (+0000)
Subject: netfilter: use jump_label for nf_hooks
X-Git-Tag: v3.3-rc1~182^2~522
X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=a2d7ec58ac09f30ab726f216827f7c7095b2a98f;p=pandora-kernel.git

netfilter: use jump_label for nf_hooks

On configs where CONFIG_JUMP_LABEL=y, we can replace in fast path a
load/compare/conditional jump by a single jump with no dcache reference.

Jump target is modified as soon as nf_hooks[pf][hook] switches from
empty state to non empty states. jump_label state is kept outside of
nf_hooks array so has no cost on cpu caches.

This patch removes the test on CONFIG_NETFILTER_DEBUG : No need to call
nf_hook_slow() at all if nf_hooks[pf][hook] is empty, this didnt give
useful information, but slowed down things a lot.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
CC: Patrick McHardy <kaber@trash.net>
CC: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
---

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