ipv4: use l4 hash for locally generated multipath flows
authorPaolo Abeni <pabeni@redhat.com>
Thu, 29 Oct 2015 21:20:40 +0000 (22:20 +0100)
committerDavid S. Miller <davem@davemloft.net>
Mon, 2 Nov 2015 19:38:43 +0000 (14:38 -0500)
This patch changes how the multipath hash is computed for locally
generated flows: now the hash comprises l4 information.

This allows better utilization of the available paths when the existing
flows have the same source IP and the same destination IP: with l3 hash,
even when multiple connections are in place simultaneously, a single path
will be used, while with l4 hash we can use all the available paths.

v2 changes:
- use get_hash_from_flowi4() instead of implementing just another l4 hash
  function

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net/ipv4/fib_semantics.c

index 42778d9d71e532cf658d8aabd37d178d06ebb081..f30df0ee4f4d8b93814d6f24aa6e020ce381c40c 100644 (file)
@@ -1564,7 +1564,8 @@ void fib_select_path(struct net *net, struct fib_result *res,
 #ifdef CONFIG_IP_ROUTE_MULTIPATH
        if (res->fi->fib_nhs > 1 && fl4->flowi4_oif == 0) {
                if (mp_hash < 0)
-                       mp_hash = fib_multipath_hash(fl4->saddr, fl4->daddr);
+                       mp_hash = get_hash_from_flowi4(fl4) >> 1;
+
                fib_select_multipath(res, mp_hash);
        }
        else