commit 0ed8ddf4045fcfcac36bad753dc4046118c603ec
author Eric Dumazet <eric.dumazet@gmail.com> Thu Oct 07 10:44:07 2010 +0000
committer David S. Miller <davem@davemloft.net> Mon Oct 11 12:54:04 2010 -0700
tree cf1d9eb14668c4d2257b3519ed7deec8c5cb396d
parent d122179a3c0fdc71b88cb9e3605f372b1651a9ff

neigh: Protect neigh->ha[] with a seqlock

Add a seqlock in struct neighbour to protect neigh->ha[], and avoid
dirtying neighbour in stress situation (many different flows / dsts)

Dirtying takes place because of read_lock(&n->lock) and n->used writes.

Switching to a seqlock, and writing n->used only on jiffies changes
permits less dirtying.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>