inet: Minimize use of cached route inetpeer.

Only use it in the absolutely required cases:

1) COW'ing metrics

2) ipv4 PMTU

3) ipv4 redirects

Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 17 insertions, 5 deletions

diff --git a/net/ipv6/icmp.c b/net/ipv6/icmp.c
index c7da1422cbde..a113f7d7e938 100644
--- a/net/ipv6/icmp.c
+++ b/net/ipv6/icmp.c
@@ -194,8 +194,10 @@ static inline bool icmpv6_xrlim_allow(struct sock *sk, u8 type,
                 if (rt->rt6i_dst.plen < 128)
                         tmo >>= ((128 - rt->rt6i_dst.plen)>>5);
 
-                peer = rt6_get_peer_create(rt);
+                peer = inet_getpeer_v6(net->ipv6.peers, &rt->rt6i_dst.addr, 1);
                 res = inet_peer_xrlim_allow(peer, tmo);
+                if (peer)
+                        inet_putpeer(peer);
         }
         dst_release(dst);
         return res;
diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
index c6af5963a202..5b2d63ed793e 100644
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -466,13 +466,15 @@ int ip6_forward(struct sk_buff *skb)
                 else
                         target = &hdr->daddr;
 
-                peer = rt6_get_peer_create(rt);
+                peer = inet_getpeer_v6(net->ipv6.peers, &rt->rt6i_dst.addr, 1);
 
                 /* Limit redirects both by destination (here)
                    and by source (inside ndisc_send_redirect)
                  */
                 if (inet_peer_xrlim_allow(peer, 1*HZ))
                         ndisc_send_redirect(skb, target);
+                if (peer)
+                        inet_putpeer(peer);
         } else {
                 int addrtype = ipv6_addr_type(&hdr->saddr);
 
@@ -592,10 +594,14 @@ void ipv6_select_ident(struct frag_hdr *fhdr, struct rt6_info *rt)
         int old, new;
 
         if (rt && !(rt->dst.flags & DST_NOPEER)) {
-                struct inet_peer *peer = rt6_get_peer_create(rt);
+                struct inet_peer *peer;
+                struct net *net;
 
+                net = dev_net(rt->dst.dev);
+                peer = inet_getpeer_v6(net->ipv6.peers, &rt->rt6i_dst.addr, 1);
                 if (peer) {
                         fhdr->identification = htonl(inet_getid(peer, 0));
+                        inet_putpeer(peer);
                         return;
                 }
         }
diff --git a/net/ipv6/ndisc.c b/net/ipv6/ndisc.c
index 69a6330dea91..0fddd571400d 100644
--- a/net/ipv6/ndisc.c
+++ b/net/ipv6/ndisc.c
@@ -1486,6 +1486,7 @@ void ndisc_send_redirect(struct sk_buff *skb, const struct in6_addr *target)
         int rd_len;
         int err;
         u8 ha_buf[MAX_ADDR_LEN], *ha = NULL;
+        bool ret;
 
         if (ipv6_get_lladdr(dev, &saddr_buf, IFA_F_TENTATIVE)) {
                 ND_PRINTK(2, warn, "Redirect: no link-local address on %s\n",
@@ -1519,8 +1520,11 @@ void ndisc_send_redirect(struct sk_buff *skb, const struct in6_addr *target)
                           "Redirect: destination is not a neighbour\n");
                 goto release;
         }
-        peer = rt6_get_peer_create(rt);
-        if (!inet_peer_xrlim_allow(peer, 1*HZ))
+        peer = inet_getpeer_v6(net->ipv6.peers, &rt->rt6i_dst.addr, 1);
+        ret = inet_peer_xrlim_allow(peer, 1*HZ);
+        if (peer)
+                inet_putpeer(peer);
+        if (!ret)
                 goto release;
 
         if (dev->addr_len) {