From 2452a99dc0496a90abd0090c280671370c0f3e1c Mon Sep 17 00:00:00 2001 From: Changli Gao Date: Mon, 2 Aug 2010 17:35:49 +0200 Subject: netfilter: nf_nat: don't check if the tuple is unique when there isn't any other choice The tuple got from unique_tuple() doesn't need to be really unique, so the check for the unique tuple isn't necessary, when there isn't any other choice. Eliminating the unnecessary nf_nat_used_tuple() can save some CPU cycles too. Signed-off-by: Changli Gao Signed-off-by: Patrick McHardy diff --git a/net/ipv4/netfilter/nf_nat_proto_common.c b/net/ipv4/netfilter/nf_nat_proto_common.c index 2844a03..3e61faf 100644 --- a/net/ipv4/netfilter/nf_nat_proto_common.c +++ b/net/ipv4/netfilter/nf_nat_proto_common.c @@ -81,9 +81,9 @@ void nf_nat_proto_unique_tuple(struct nf_conntrack_tuple *tuple, else off = *rover; - for (i = 0; i < range_size; i++, off++) { + for (i = 0; ; ++off) { *portptr = htons(min + off % range_size); - if (nf_nat_used_tuple(tuple, ct)) + if (++i != range_size && nf_nat_used_tuple(tuple, ct)) continue; if (!(range->flags & IP_NAT_RANGE_PROTO_RANDOM)) *rover = off; diff --git a/net/ipv4/netfilter/nf_nat_proto_gre.c b/net/ipv4/netfilter/nf_nat_proto_gre.c index 89933ab..bc8d83a 100644 --- a/net/ipv4/netfilter/nf_nat_proto_gre.c +++ b/net/ipv4/netfilter/nf_nat_proto_gre.c @@ -68,9 +68,9 @@ gre_unique_tuple(struct nf_conntrack_tuple *tuple, pr_debug("min = %u, range_size = %u\n", min, range_size); - for (i = 0; i < range_size; i++, key++) { + for (i = 0; ; ++key) { *keyptr = htons(min + key % range_size); - if (!nf_nat_used_tuple(tuple, ct)) + if (++i == range_size || !nf_nat_used_tuple(tuple, ct)) return; } diff --git a/net/ipv4/netfilter/nf_nat_proto_icmp.c b/net/ipv4/netfilter/nf_nat_proto_icmp.c index 97003fe..5744c3e 100644 --- a/net/ipv4/netfilter/nf_nat_proto_icmp.c +++ b/net/ipv4/netfilter/nf_nat_proto_icmp.c @@ -42,10 +42,10 @@ icmp_unique_tuple(struct nf_conntrack_tuple *tuple, if (!(range->flags & IP_NAT_RANGE_PROTO_SPECIFIED)) range_size = 0xFFFF; - for (i = 0; i < range_size; i++, id++) { + for (i = 0; ; ++id) { tuple->src.u.icmp.id = htons(ntohs(range->min.icmp.id) + (id % range_size)); - if (!nf_nat_used_tuple(tuple, ct)) + if (++i == range_size || !nf_nat_used_tuple(tuple, ct)) return; } return; -- cgit v0.10.2