tcp: connect() from bound sockets can be faster

__inet_hash_connect() does not use its third argument (port_offset)
if socket was already bound to a source port.

No need to perform useless but expensive md5 computations.

Reported-by: Crestez Dan Leonard <cdleonard@gmail.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 6 insertions, 2 deletions

diff --git a/net/ipv6/inet6_hashtables.c b/net/ipv6/inet6_hashtables.c
index 871641bc1ed4..b4fd96de97e6 100644
--- a/net/ipv6/inet6_hashtables.c
+++ b/net/ipv6/inet6_hashtables.c
@@ -257,7 +257,7 @@ not_unique:
         return -EADDRNOTAVAIL;
 }
 
-static inline u32 inet6_sk_port_offset(const struct sock *sk)
+static u32 inet6_sk_port_offset(const struct sock *sk)
 {
         const struct inet_sock *inet = inet_sk(sk);
 
@@ -269,7 +269,11 @@ static inline u32 inet6_sk_port_offset(const struct sock *sk)
 int inet6_hash_connect(struct inet_timewait_death_row *death_row,
                        struct sock *sk)
 {
-        return __inet_hash_connect(death_row, sk, inet6_sk_port_offset(sk),
+        u32 port_offset = 0;
+
+        if (!inet_sk(sk)->inet_num)
+                port_offset = inet6_sk_port_offset(sk);
+        return __inet_hash_connect(death_row, sk, port_offset,
                                    __inet6_check_established);
 }
 EXPORT_SYMBOL_GPL(inet6_hash_connect);