From 3769cffb1c48f64640ffab7ce3bffe867342c0f0 Mon Sep 17 00:00:00 2001 From: David Miller Date: Mon, 11 Jul 2011 22:44:24 +0000 Subject: ipv4: Inline neigh binding. Get rid of all of the useless and costly indirection by doing the neigh hash table lookup directly inside of the neighbour binding. Rename from arp_bind_neighbour to rt_bind_neighbour. Use new helpers {__,}ipv4_neigh_lookup() In rt_bind_neighbour() get rid of useless tests which are never true in the context this function is called, namely dev is never NULL and the dst->neighbour is always NULL. Signed-off-by: David S. Miller --- include/net/arp.h | 33 ++++++++++++++++++++++++++++++++- 1 file changed, 32 insertions(+), 1 deletion(-) (limited to 'include/net') diff --git a/include/net/arp.h b/include/net/arp.h index 723bde501c64..5e669e6ffb42 100644 --- a/include/net/arp.h +++ b/include/net/arp.h @@ -15,6 +15,38 @@ 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 neigh_table *tbl, struct net_device *dev, u32 key) +{ + struct neigh_hash_table *nht; + struct neighbour *n; + u32 hash_val; + + rcu_read_lock_bh(); + nht = rcu_dereference_bh(tbl->nht); + hash_val = arp_hashfn(key, dev, nht->hash_rnd) >> (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; + } + } + rcu_read_unlock_bh(); + + return n; +} + +static inline struct neighbour *ipv4_neigh_lookup(struct neigh_table *tbl, struct net_device *dev, const __be32 *pkey) +{ + struct neighbour *n = __ipv4_neigh_lookup(tbl, dev, + *(__force u32 *)pkey); + if (n) + return n; + return neigh_create(tbl, pkey, dev); +} + extern void arp_init(void); extern int arp_find(unsigned char *haddr, struct sk_buff *skb); extern int arp_ioctl(struct net *net, unsigned int cmd, void __user *arg); @@ -22,7 +54,6 @@ extern void arp_send(int type, int ptype, __be32 dest_ip, struct net_device *dev, __be32 src_ip, const unsigned char *dest_hw, const unsigned char *src_hw, const unsigned char *th); -extern int arp_bind_neighbour(struct dst_entry *dst); extern int arp_mc_map(__be32 addr, u8 *haddr, struct net_device *dev, int dir); extern void arp_ifdown(struct net_device *dev); -- cgit v1.2.3