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 <xiaosuo@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
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 @@
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;