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>
This commit is contained in:
Changli Gao 2010-08-02 17:35:49 +02:00 committed by Patrick McHardy
parent f43dc98b3b
commit 2452a99dc0
3 changed files with 6 additions and 6 deletions

View file

@ -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;

View file

@ -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;
}

View file

@ -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;