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 <davem@davemloft.net>
diff --git a/include/net/arp.h b/include/net/arp.h
index 4a1f3fb..4617d98 100644
--- a/include/net/arp.h
+++ b/include/net/arp.h
@@ -15,24 +15,34 @@
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;