From a263b3093641fb1ec377582c90986a7fd0625184 Mon Sep 17 00:00:00 2001 From: "David S. Miller" Date: Mon, 2 Jul 2012 02:02:15 -0700 Subject: ipv4: Make neigh lookups directly in output packet path. Do not use the dst cached neigh, we'll be getting rid of that. Signed-off-by: David S. Miller --- include/net/arp.h | 28 +++++++++++++++++++--------- 1 file changed, 19 insertions(+), 9 deletions(-) (limited to 'include/net/arp.h') diff --git a/include/net/arp.h b/include/net/arp.h index 4a1f3fb562eb..4617d9841132 100644 --- a/include/net/arp.h +++ b/include/net/arp.h @@ -15,24 +15,34 @@ static inline u32 arp_hashfn(u32 key, const struct net_device *dev, u32 hash_rnd return val * hash_rnd; } -static inline struct neighbour *__ipv4_neigh_lookup(struct net_device *dev, u32 key) +static inline struct neighbour *__ipv4_neigh_lookup_noref(struct net_device *dev, u32 key) { - struct neigh_hash_table *nht; + struct neigh_hash_table *nht = rcu_dereference_bh(arp_tbl.nht); struct neighbour *n; u32 hash_val; - rcu_read_lock_bh(); - nht = rcu_dereference_bh(arp_tbl.nht); + if (dev->flags & (IFF_LOOPBACK | IFF_POINTOPOINT)) + key = 0; + hash_val = arp_hashfn(key, dev, nht->hash_rnd[0]) >> (32 - nht->hash_shift); for (n = rcu_dereference_bh(nht->hash_buckets[hash_val]); n != NULL; n = rcu_dereference_bh(n->next)) { - if (n->dev == dev && *(u32 *)n->primary_key == key) { - if (!atomic_inc_not_zero(&n->refcnt)) - n = NULL; - break; - } + if (n->dev == dev && *(u32 *)n->primary_key == key) + return n; } + + return NULL; +} + +static inline struct neighbour *__ipv4_neigh_lookup(struct net_device *dev, u32 key) +{ + struct neighbour *n; + + rcu_read_lock_bh(); + n = __ipv4_neigh_lookup_noref(dev, key); + if (n && !atomic_inc_not_zero(&n->refcnt)) + n = NULL; rcu_read_unlock_bh(); return n; -- cgit v1.2.3