tree a4c6bc690e612da44dab7e8beb71c5c0bdb8b6ba
parent d527043040740f41192dfd71793f905a998ee4f6
author Eric Dumazet <edumazet@google.com> 1360255262 +0000
committer David S. Miller <davem@davemloft.net> 1360364148 -0500

macvlan: add a salt to mc_hash()

Some multicast addresses are common to all macvlans,
so if a multicast message has a hash value collision, we
have to deliver a copy to all macvlans, adding significant
latency and possible packet drops if netdev_max_backlog
limit is hit.

Having a per macvlan hash function permits to reduce the
impact of hash collisions.

Suggested-by: Maciej Żenczykowski <maze@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>