inet: Minimize use of cached route inetpeer.
authorDavid S. Miller <davem@davemloft.net>
Tue, 10 Jul 2012 10:58:16 +0000 (03:58 -0700)
committerDavid S. Miller <davem@davemloft.net>
Wed, 11 Jul 2012 05:40:11 +0000 (22:40 -0700)
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>
net/ipv4/icmp.c
net/ipv4/route.c
net/ipv6/icmp.c
net/ipv6/ip6_output.c
net/ipv6/ndisc.c

index 4bce5a2..4a04944 100644 (file)
@@ -254,9 +254,10 @@ static inline bool icmpv4_xrlim_allow(struct net *net, struct rtable *rt,
 
        /* Limit if icmp type is enabled in ratemask. */
        if ((1 << type) & net->ipv4.sysctl_icmp_ratemask) {
-               struct inet_peer *peer = rt_get_peer_create(rt, fl4->daddr);
+               struct inet_peer *peer = inet_getpeer_v4(net->ipv4.peers, fl4->daddr, 1);
                rc = inet_peer_xrlim_allow(peer,
                                           net->ipv4.sysctl_icmp_ratelimit);
+               inet_putpeer(peer);
        }
 out:
        return rc;
index 78d8154..e376354 100644 (file)
@@ -1289,20 +1289,15 @@ static void ip_select_fb_ident(struct iphdr *iph)
 
 void __ip_select_ident(struct iphdr *iph, struct dst_entry *dst, int more)
 {
-       struct rtable *rt = (struct rtable *) dst;
-
-       if (rt && !(rt->dst.flags & DST_NOPEER)) {
-               struct inet_peer *peer = rt_get_peer_create(rt, rt->rt_dst);
+       struct net *net = dev_net(dst->dev);
+       struct inet_peer *peer;
 
-               /* If peer is attached to destination, it is never detached,
-                  so that we need not to grab a lock to dereference it.
-                */
-               if (peer) {
-                       iph->id = htons(inet_getid(peer, more));
-                       return;
-               }
-       } else if (!rt)
-               pr_debug("rt_bind_peer(0) @%p\n", __builtin_return_address(0));
+       peer = inet_getpeer_v4(net->ipv4.peers, iph->daddr, 1);
+       if (peer) {
+               iph->id = htons(inet_getid(peer, more));
+               inet_putpeer(peer);
+               return;
+       }
 
        ip_select_fb_ident(iph);
 }
@@ -1492,6 +1487,7 @@ void ip_rt_send_redirect(struct sk_buff *skb)
        struct rtable *rt = skb_rtable(skb);
        struct in_device *in_dev;
        struct inet_peer *peer;
+       struct net *net;
        int log_martians;
 
        rcu_read_lock();
@@ -1503,7 +1499,8 @@ void ip_rt_send_redirect(struct sk_buff *skb)
        log_martians = IN_DEV_LOG_MARTIANS(in_dev);
        rcu_read_unlock();
 
-       peer = rt_get_peer_create(rt, rt->rt_dst);
+       net = dev_net(rt->dst.dev);
+       peer = inet_getpeer_v4(net->ipv4.peers, ip_hdr(skb)->saddr, 1);
        if (!peer) {
                icmp_send(skb, ICMP_REDIRECT, ICMP_REDIR_HOST, rt->rt_gateway);
                return;
@@ -1520,7 +1517,7 @@ void ip_rt_send_redirect(struct sk_buff *skb)
         */
        if (peer->rate_tokens >= ip_rt_redirect_number) {
                peer->rate_last = jiffies;
-               return;
+               goto out_put_peer;
        }
 
        /* Check for load limit; set rate_last to the latest sent
@@ -1541,6 +1538,8 @@ void ip_rt_send_redirect(struct sk_buff *skb)
                                             &rt->rt_dst, &rt->rt_gateway);
 #endif
        }
+out_put_peer:
+       inet_putpeer(peer);
 }
 
 static int ip_error(struct sk_buff *skb)
@@ -1583,7 +1582,7 @@ static int ip_error(struct sk_buff *skb)
                break;
        }
 
-       peer = rt_get_peer_create(rt, rt->rt_dst);
+       peer = inet_getpeer_v4(net->ipv4.peers, ip_hdr(skb)->saddr, 1);
 
        send = true;
        if (peer) {
@@ -1596,6 +1595,7 @@ static int ip_error(struct sk_buff *skb)
                        peer->rate_tokens -= ip_rt_error_cost;
                else
                        send = false;
+               inet_putpeer(peer);
        }
        if (send)
                icmp_send(skb, ICMP_DEST_UNREACH, code, 0);
index c7da142..a113f7d 100644 (file)
@@ -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;
index c6af596..5b2d63e 100644 (file)
@@ -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;
                }
        }
index 69a6330..0fddd57 100644 (file)
@@ -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) {