From: Eric Dumazet <edumazet@google.com>
Date: Wed, 27 May 2015 17:46:02 +0000 (-0700)
Subject: tcp: connect() from bound sockets can be faster
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=e2baad9e4b153c67dddc5ccf987395b842329c84;p=GitHub%2FLineageOS%2FG12%2Fandroid_kernel_amlogic_linux-4.9.git

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>
---

diff --git a/net/ipv4/inet_hashtables.c b/net/ipv4/inet_hashtables.c
index 1b336dc179f8..5f9b063bbe8a 100644
--- a/net/ipv4/inet_hashtables.c
+++ b/net/ipv4/inet_hashtables.c
@@ -394,9 +394,10 @@ not_unique:
 	return -EADDRNOTAVAIL;
 }
 
-static inline u32 inet_sk_port_offset(const struct sock *sk)
+static u32 inet_sk_port_offset(const struct sock *sk)
 {
 	const struct inet_sock *inet = inet_sk(sk);
+
 	return secure_ipv4_port_ephemeral(inet->inet_rcv_saddr,
 					  inet->inet_daddr,
 					  inet->inet_dport);
@@ -600,7 +601,11 @@ out:
 int inet_hash_connect(struct inet_timewait_death_row *death_row,
 		      struct sock *sk)
 {
-	return __inet_hash_connect(death_row, sk, inet_sk_port_offset(sk),
+	u32 port_offset = 0;
+
+	if (!inet_sk(sk)->inet_num)
+		port_offset = inet_sk_port_offset(sk);
+	return __inet_hash_connect(death_row, sk, port_offset,
 				   __inet_check_established);
 }
 EXPORT_SYMBOL_GPL(inet_hash_connect);
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);