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ipv4: Inline neigh binding.

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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 <davem@davemloft.net>
This commit is contained in:
David Miller
2011-07-11 22:44:24 +00:00
committed by David S. Miller
parent e5b1de1f5e
commit 3769cffb1c
3 changed files with 59 additions and 28 deletions
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33
include/net/arp.h
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@@ -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);