[Devel] [PATCH net-2.6.25 (resend) 1/3] Uninline the __inet_hash function

[Pavel Emelyanov]

This one is used in quite many places in the networking code and
seems to big to be inline.

After the patch net/ipv4/build-in.o loses ~650 bytes:
add/remove: 2/0 grow/shrink: 0/5 up/down: 461/-1114 (-653)
function                                     old     new   delta
__inet_hash_nolisten                           -     282    +282
__inet_hash                                    -     179    +179
tcp_sacktag_write_queue                     2255    2254      -1
__inet_lookup_listener                       284     274     -10
tcp_v4_syn_recv_sock                         755     493    -262
tcp_v4_hash                                  389      35    -354
inet_hash_connect                           1086     599    -487

This version addresses the issue pointed by Eric, that
while being inline this function was optimized by gcc
in respect to the 'listen_possible' argument.

(Patches 2 and 3 in this series are still applied after this)

Signed-off-by: Pavel Emelyanov <xemul at openvz.org>

---

diff --git a/include/net/inet_hashtables.h b/include/net/inet_hashtables.h
index fef4442..65ddb25 100644
--- a/include/net/inet_hashtables.h
+++ b/include/net/inet_hashtables.h
@@ -264,37 +264,14 @@ static inline void inet_listen_unlock(struct inet_hashinfo *hashinfo)
 		wake_up(&hashinfo->lhash_wait);
 }
 
-static inline void __inet_hash(struct inet_hashinfo *hashinfo,
-			       struct sock *sk, const int listen_possible)
-{
-	struct hlist_head *list;
-	rwlock_t *lock;
-
-	BUG_TRAP(sk_unhashed(sk));
-	if (listen_possible && sk->sk_state == TCP_LISTEN) {
-		list = &hashinfo->listening_hash[inet_sk_listen_hashfn(sk)];
-		lock = &hashinfo->lhash_lock;
-		inet_listen_wlock(hashinfo);
-	} else {
-		struct inet_ehash_bucket *head;
-		sk->sk_hash = inet_sk_ehashfn(sk);
-		head = inet_ehash_bucket(hashinfo, sk->sk_hash);
-		list = &head->chain;
-		lock = inet_ehash_lockp(hashinfo, sk->sk_hash);
-		write_lock(lock);
-	}
-	__sk_add_node(sk, list);
-	sock_prot_inc_use(sk->sk_prot);
-	write_unlock(lock);
-	if (listen_possible && sk->sk_state == TCP_LISTEN)
-		wake_up(&hashinfo->lhash_wait);
-}
+extern void __inet_hash(struct inet_hashinfo *hashinfo, struct sock *sk);
+extern void __inet_hash_nolisten(struct inet_hashinfo *hinfo, struct sock *sk);
 
 static inline void inet_hash(struct inet_hashinfo *hashinfo, struct sock *sk)
 {
 	if (sk->sk_state != TCP_CLOSE) {
 		local_bh_disable();
-		__inet_hash(hashinfo, sk, 1);
+		__inet_hash(hashinfo, sk);
 		local_bh_enable();
 	}
 }
diff --git a/net/dccp/ipv4.c b/net/dccp/ipv4.c
index 02fc91c..f450df2 100644
--- a/net/dccp/ipv4.c
+++ b/net/dccp/ipv4.c
@@ -408,7 +408,7 @@ struct sock *dccp_v4_request_recv_sock(struct sock *sk, struct sk_buff *skb,
 
 	dccp_sync_mss(newsk, dst_mtu(dst));
 
-	__inet_hash(&dccp_hashinfo, newsk, 0);
+	__inet_hash_nolisten(&dccp_hashinfo, newsk);
 	__inet_inherit_port(&dccp_hashinfo, sk, newsk);
 
 	return newsk;
diff --git a/net/ipv4/inet_hashtables.c b/net/ipv4/inet_hashtables.c
index b07e2d3..2e5814a 100644
--- a/net/ipv4/inet_hashtables.c
+++ b/net/ipv4/inet_hashtables.c
@@ -305,6 +305,48 @@ static inline u32 inet_sk_port_offset(const struct sock *sk)
 					  inet->dport);
 }
 
+void __inet_hash_nolisten(struct inet_hashinfo *hashinfo, struct sock *sk)
+{
+	struct hlist_head *list;
+	rwlock_t *lock;
+	struct inet_ehash_bucket *head;
+
+	BUG_TRAP(sk_unhashed(sk));
+
+	sk->sk_hash = inet_sk_ehashfn(sk);
+	head = inet_ehash_bucket(hashinfo, sk->sk_hash);
+	list = &head->chain;
+	lock = inet_ehash_lockp(hashinfo, sk->sk_hash);
+
+	write_lock(lock);
+	__sk_add_node(sk, list);
+	sock_prot_inc_use(sk->sk_prot);
+	write_unlock(lock);
+}
+EXPORT_SYMBOL_GPL(__inet_hash_nolisten);
+
+void __inet_hash(struct inet_hashinfo *hashinfo, struct sock *sk)
+{
+	struct hlist_head *list;
+	rwlock_t *lock;
+
+	if (sk->sk_state != TCP_LISTEN) {
+		__inet_hash_nolisten(hashinfo, sk);
+		return;
+	}
+
+	BUG_TRAP(sk_unhashed(sk));
+	list = &hashinfo->listening_hash[inet_sk_listen_hashfn(sk)];
+	lock = &hashinfo->lhash_lock;
+
+	inet_listen_wlock(hashinfo);
+	__sk_add_node(sk, list);
+	sock_prot_inc_use(sk->sk_prot);
+	write_unlock(lock);
+	wake_up(&hashinfo->lhash_wait);
+}
+EXPORT_SYMBOL_GPL(__inet_hash);
+
 /*
  * Bind a port for a connect operation and hash it.
  */
@@ -372,7 +414,7 @@ ok:
 		inet_bind_hash(sk, tb, port);
 		if (sk_unhashed(sk)) {
 			inet_sk(sk)->sport = htons(port);
-			__inet_hash(hinfo, sk, 0);
+			__inet_hash_nolisten(hinfo, sk);
 		}
 		spin_unlock(&head->lock);
 
@@ -389,7 +431,7 @@ ok:
 	tb  = inet_csk(sk)->icsk_bind_hash;
 	spin_lock_bh(&head->lock);
 	if (sk_head(&tb->owners) == sk && !sk->sk_bind_node.next) {
-		__inet_hash(hinfo, sk, 0);
+		__inet_hash_nolisten(hinfo, sk);
 		spin_unlock_bh(&head->lock);
 		return 0;
 	} else {
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index 652c323..fc9bdd8 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -1478,7 +1478,7 @@ struct sock *tcp_v4_syn_recv_sock(struct sock *sk, struct sk_buff *skb,
 	}
 #endif
 
-	__inet_hash(&tcp_hashinfo, newsk, 0);
+	__inet_hash_nolisten(&tcp_hashinfo, newsk);
 	__inet_inherit_port(&tcp_hashinfo, sk, newsk);
 
 	return newsk;