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 <davem@davemloft.net>

1 files changed, 27 insertions, 3 deletions

diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index a8ccd9bca09c..c6388e825ed3 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -108,6 +108,7 @@
 #ifdef CONFIG_SYSCTL
 #include <linux/sysctl.h>
 #endif
+#include <net/atmclip.h>
 
 #define RT_FL_TOS(oldflp4) \
     ((u32)(oldflp4->flowi4_tos & (IPTOS_RT_MASK | RTO_ONLINK)))
@@ -1006,6 +1007,29 @@ static int slow_chain_length(const struct rtable *head)
         return length >> FRACT_BITS;
 }
 
+static int rt_bind_neighbour(struct rtable *rt)
+{
+        static const __be32 inaddr_any = 0;
+        struct net_device *dev = rt->dst.dev;
+        struct neigh_table *tbl = &arp_tbl;
+        const __be32 *nexthop;
+        struct neighbour *n;
+
+#if defined(CONFIG_ATM_CLIP) || defined(CONFIG_ATM_CLIP_MODULE)
+        if (dev->type == ARPHRD_ATM)
+                tbl = clip_tbl_hook;
+#endif
+        nexthop = &rt->rt_gateway;
+        if (dev->flags & (IFF_LOOPBACK | IFF_POINTOPOINT))
+                nexthop = &inaddr_any;
+        n = ipv4_neigh_lookup(tbl, dev, nexthop);
+        if (IS_ERR(n))
+                return PTR_ERR(n);
+        rt->dst.neighbour = n;
+
+        return 0;
+}
+
 static struct rtable *rt_intern_hash(unsigned hash, struct rtable *rt,
                                      struct sk_buff *skb, int ifindex)
 {
@@ -1042,7 +1066,7 @@ restart:
 
                 rt->dst.flags |= DST_NOCACHE;
                 if (rt->rt_type == RTN_UNICAST || rt_is_output_route(rt)) {
-                        int err = arp_bind_neighbour(&rt->dst);
+                        int err = rt_bind_neighbour(rt);
                         if (err) {
                                 if (net_ratelimit())
                                         printk(KERN_WARNING
@@ -1138,7 +1162,7 @@ restart:
            route or unicast forwarding path.
          */
         if (rt->rt_type == RTN_UNICAST || rt_is_output_route(rt)) {
-                int err = arp_bind_neighbour(&rt->dst);
+                int err = rt_bind_neighbour(rt);
                 if (err) {
                         spin_unlock_bh(rt_hash_lock_addr(hash));
 
@@ -1599,7 +1623,7 @@ static int check_peer_redir(struct dst_entry *dst, struct inet_peer *peer)
         rt->dst.neighbour = NULL;
 
         rt->rt_gateway = peer->redirect_learned.a4;
-        if (arp_bind_neighbour(&rt->dst) ||
+        if (rt_bind_neighbour(rt) ||
             !(rt->dst.neighbour->nud_state & NUD_VALID)) {
                 if (rt->dst.neighbour)
                         neigh_event_send(rt->dst.neighbour, NULL);