From: Li RongQing <lirongqing@baidu.com>
Date: Tue, 26 Feb 2019 09:20:52 +0000 (+0800)
Subject: netfilter: nf_conntrack: ensure that CONNTRACK_LOCKS is power of 2
X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=2e7b162c5e911050be84c86c6226a5e21bba5771;p=openwrt%2Fstaging%2Fblogic.git

netfilter: nf_conntrack: ensure that CONNTRACK_LOCKS is power of 2

CONNTRACK_LOCKS is divisor when computer array index, if it is power of
2, compiler will optimize modulo operation as bitwise AND, or else
modulo will lower performance.

Suggested-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Li RongQing <lirongqing@baidu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---

diff --git a/net/netfilter/nf_conntrack_core.c b/net/netfilter/nf_conntrack_core.c
index ff9313c579b4..82bfbeef46af 100644
--- a/net/netfilter/nf_conntrack_core.c
+++ b/net/netfilter/nf_conntrack_core.c
@@ -2480,6 +2480,7 @@ int nf_conntrack_init_net(struct net *net)
 	int cpu;
 
 	BUILD_BUG_ON(IP_CT_UNTRACKED == IP_CT_NUMBER);
+	BUILD_BUG_ON_NOT_POWER_OF_2(CONNTRACK_LOCKS);
 	atomic_set(&net->ct.count, 0);
 
 	net->ct.pcpu_lists = alloc_percpu(struct ct_pcpu);