[IPV6] NEIGH: Optimize is_router check.

Our interest is not the whole entry of proxy neighbor but the
NTF_ROUTER flag.  Let's test it explicitly.

Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>

diff --git a/net/ipv6/ndisc.c b/net/ipv6/ndisc.c
index e77b74e..510aa74 100644 (file)
--- a/net/ipv6/ndisc.c
+++ b/net/ipv6/ndisc.c
@@ -661,18 +661,19 @@ static void ndisc_solicit(struct neighbour *neigh, struct sk_buff *skb)
        }
 }
 
-static struct pneigh_entry *pndisc_check_router(struct net_device *dev,
-               struct in6_addr *addr, int *is_router)
+static int pndisc_is_router(const void *pkey,
+                           struct net_device *dev)
 {
        struct pneigh_entry *n;
+       int ret = -1;
 
        read_lock_bh(&nd_tbl.lock);
-       n = __pneigh_lookup(&nd_tbl, dev_net(dev), addr, dev);
-       if (n != NULL)
-               *is_router = (n->flags & NTF_ROUTER);
+       n = __pneigh_lookup(&nd_tbl, dev_net(dev), pkey, dev);
+       if (n)
+               ret = !!(n->flags & NTF_ROUTER);
        read_unlock_bh(&nd_tbl.lock);
 
-       return n;
+       return ret;
 }
 
 static void ndisc_recv_ns(struct sk_buff *skb)
@@ -688,10 +689,9 @@ static void ndisc_recv_ns(struct sk_buff *skb)
        struct inet6_ifaddr *ifp;
        struct inet6_dev *idev = NULL;
        struct neighbour *neigh;
-       struct pneigh_entry *pneigh = NULL;
        int dad = ipv6_addr_any(saddr);
        int inc;
-       int is_router = 0;
+       int is_router = -1;
 
        if (ipv6_addr_is_multicast(&msg->target)) {
                ND_PRINTK2(KERN_WARNING
@@ -790,8 +790,7 @@ static void ndisc_recv_ns(struct sk_buff *skb)
                if (ipv6_chk_acast_addr(dev_net(dev), dev, &msg->target) ||
                    (idev->cnf.forwarding &&
                     (ipv6_devconf.proxy_ndp || idev->cnf.proxy_ndp) &&
-                    (pneigh = pndisc_check_router(dev, &msg->target,
-                                                 &is_router)) != NULL)) {
+                    (is_router = pndisc_is_router(&msg->target, dev)) >= 0)) {
                        if (!(NEIGH_CB(skb)->flags & LOCALLY_ENQUEUED) &&
                            skb->pkt_type != PACKET_HOST &&
                            inc != 0 &&
@@ -812,7 +811,8 @@ static void ndisc_recv_ns(struct sk_buff *skb)
                        goto out;
        }
 
-       is_router = !!(pneigh ? is_router : idev->cnf.forwarding);
+       if (is_router < 0)
+               is_router = !!idev->cnf.forwarding;
 
        if (dad) {
                struct in6_addr maddr;