diff mbox

[net-next,v2,3/5] ipv6: Use multipath hash from flow info if available

Message ID 1477657955-5157-4-git-send-email-jkbs@redhat.com
State Changes Requested, archived
Delegated to: David Miller
Headers show

Commit Message

Jakub Sitnicki Oct. 28, 2016, 12:32 p.m. UTC 
Allow our callers to influence the choice of ECMP link by honoring the
hash passed together with the flow info. This will allow for special
treatment of ICMP errors which we would like to route over the same link
as the IP datagram that triggered the error.

Signed-off-by: Jakub Sitnicki <jkbs@redhat.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
---
 net/ipv6/route.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)
diff mbox

Patch

diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index 0514b35..1184c2b 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -430,9 +430,11 @@  static struct rt6_info *rt6_multipath_select(struct rt6_info *match,
 					     int strict)
 {
 	struct rt6_info *sibling, *next_sibling;
+	unsigned int hash;
 	int route_choosen;
 
-	route_choosen = get_hash_from_flowi6(fl6) % (match->rt6i_nsiblings + 1);
+	hash = fl6->mp_hash ? : get_hash_from_flowi6(fl6);
+	route_choosen = hash % (match->rt6i_nsiblings + 1);
 	/* Don't change the route, if route_choosen == 0
 	 * (siblings does not include ourself)
 	 */