ipv6: make lookups simpler and faster

TCP listener refactoring, part 4 :

To speed up inet lookups, we moved IPv4 addresses from inet to struct
sock_common

Now is time to do the same for IPv6, because it permits us to have fast
lookups for all kind of sockets, including upcoming SYN_RECV.

Getting IPv6 addresses in TCP lookups currently requires two extra cache
lines, plus a dereference (and memory stall).

inet6_sk(sk) does the dereference of inet_sk(__sk)->pinet6

This patch is way bigger than its IPv4 counter part, because for IPv4,
we could add aliases (inet_daddr, inet_rcv_saddr), while on IPv6,
it's not doable easily.

inet6_sk(sk)->daddr becomes sk->sk_v6_daddr
inet6_sk(sk)->rcv_saddr becomes sk->sk_v6_rcv_saddr

And timewait socket also have tw->tw_v6_daddr & tw->tw_v6_rcv_saddr
at the same offset.

We get rid of INET6_TW_MATCH() as INET6_MATCH() is now the generic
macro.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 4 insertions, 6 deletions

diff --git a/net/ipv4/tcp_metrics.c b/net/ipv4/tcp_metrics.c
index 52f3c6b971d2..27535fd5ea10 100644
--- a/net/ipv4/tcp_metrics.c
+++ b/net/ipv4/tcp_metrics.c
@@ -240,7 +240,6 @@ static struct tcp_metrics_block *__tcp_get_metrics_req(struct request_sock *req,
 
 static struct tcp_metrics_block *__tcp_get_metrics_tw(struct inet_timewait_sock *tw)
 {
-        struct inet6_timewait_sock *tw6;
         struct tcp_metrics_block *tm;
         struct inetpeer_addr addr;
         unsigned int hash;
@@ -253,9 +252,8 @@ static struct tcp_metrics_block *__tcp_get_metrics_tw(struct inet_timewait_sock
                 hash = (__force unsigned int) addr.addr.a4;
                 break;
         case AF_INET6:
-                tw6 = inet6_twsk((struct sock *)tw);
-                *(struct in6_addr *)addr.addr.a6 = tw6->tw_v6_daddr;
-                hash = ipv6_addr_hash(&tw6->tw_v6_daddr);
+                *(struct in6_addr *)addr.addr.a6 = tw->tw_v6_daddr;
+                hash = ipv6_addr_hash(&tw->tw_v6_daddr);
                 break;
         default:
                 return NULL;
@@ -289,8 +287,8 @@ static struct tcp_metrics_block *tcp_get_metrics(struct sock *sk,
                 hash = (__force unsigned int) addr.addr.a4;
                 break;
         case AF_INET6:
-                *(struct in6_addr *)addr.addr.a6 = inet6_sk(sk)->daddr;
-                hash = ipv6_addr_hash(&inet6_sk(sk)->daddr);
+                *(struct in6_addr *)addr.addr.a6 = sk->sk_v6_daddr;
+                hash = ipv6_addr_hash(&sk->sk_v6_daddr);
                 break;
         default:
                 return NULL;