ipsec: pfkey should ignore events when no listeners

When pfkey has no km listeners, it still does a lot of work before finding out there aint nobody out there. If a tree falls in a forest and no one is around to hear it, does it make a sound? In this case it makes a lot of noise: With this short-circuit adding 10s of thousands of SAs using netlink improves performance by ~10%. Signed-off-by: Jamal Hadi Salim <hadi@cyberus.ca> Signed-off-by: David S. Miller <davem@davemloft.net>

ipsec: pfkey should ignore events when no listeners
When pfkey has no km listeners, it still does a lot of work before finding out there aint nobody out there. If a tree falls in a forest and no one is around to hear it, does it make a sound? In this case it makes a lot of noise: With this short-circuit adding 10s of thousands of SAs using netlink improves performance by ~10%. Signed-off-by: Jamal Hadi Salim <hadi@cyberus.ca> Signed-off-by: David S. Miller <davem@davemloft.net>
Jamal Hadi Salim · David S. Miller
1 parent bc6cffd177
Showing 1 changed file with 3 additions and 0 deletions Side-by-side Diff
net/key/af_key.c
@@ -3030,6 +3030,9 @@
  
 static int pfkey_send_notify(struct xfrm_state *x, struct km_event *c)
 {
+	if (atomic_read(&pfkey_socks_nr) == 0)
+		return 0;
+
 	switch (c->event) {
 	case XFRM_MSG_EXPIRE:
 		return key_notify_sa_expire(x, c);
...	...	@@ -3030,6 +3030,9 @@
3030	3030
3031	3031	static int pfkey_send_notify(struct xfrm_state x, struct km_event c)
3032	3032	{
	3033	+ if (atomic_read(&pfkey_socks_nr) == 0)
	3034	+ return 0;
	3035	+
3033	3036	switch (c->event) {
3034	3037	case XFRM_MSG_EXPIRE:
3035	3038	return key_notify_sa_expire(x, c);