[INET]: Generalise the tcp_listen_ lock routines

Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 9 insertions, 61 deletions

diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index f5373f9f00a..5f9ad95304c 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -228,62 +228,11 @@ fail:
         return ret;
 }
 
-/* This lock without WQ_FLAG_EXCLUSIVE is good on UP and it can be very bad on SMP.
- * Look, when several writers sleep and reader wakes them up, all but one
- * immediately hit write lock and grab all the cpus. Exclusive sleep solves
- * this, _but_ remember, it adds useless work on UP machines (wake up each
- * exclusive lock release). It should be ifdefed really.
- */
-
-void tcp_listen_wlock(void)
-{
-        write_lock(&tcp_hashinfo.lhash_lock);
-
-        if (atomic_read(&tcp_hashinfo.lhash_users)) {
-                DEFINE_WAIT(wait);
-
-                for (;;) {
-                        prepare_to_wait_exclusive(&tcp_hashinfo.lhash_wait,
-                                                &wait, TASK_UNINTERRUPTIBLE);
-                        if (!atomic_read(&tcp_hashinfo.lhash_users))
-                                break;
-                        write_unlock_bh(&tcp_hashinfo.lhash_lock);
-                        schedule();
-                        write_lock_bh(&tcp_hashinfo.lhash_lock);
-                }
-
-                finish_wait(&tcp_hashinfo.lhash_wait, &wait);
-        }
-}
-
-static __inline__ void __tcp_v4_hash(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 = &tcp_hashinfo.listening_hash[inet_sk_listen_hashfn(sk)];
-                lock = &tcp_hashinfo.lhash_lock;
-                tcp_listen_wlock();
-        } else {
-                sk->sk_hashent = inet_sk_ehashfn(sk, tcp_hashinfo.ehash_size);
-                list = &tcp_hashinfo.ehash[sk->sk_hashent].chain;
-                lock = &tcp_hashinfo.ehash[sk->sk_hashent].lock;
-                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(&tcp_hashinfo.lhash_wait);
-}
-
 static void tcp_v4_hash(struct sock *sk)
 {
         if (sk->sk_state != TCP_CLOSE) {
                 local_bh_disable();
-                __tcp_v4_hash(sk, 1);
+                __inet_hash(&tcp_hashinfo, sk, 1);
                 local_bh_enable();
         }
 }
@@ -297,7 +246,7 @@ void tcp_unhash(struct sock *sk)
 
         if (sk->sk_state == TCP_LISTEN) {
                 local_bh_disable();
-                tcp_listen_wlock();
+                inet_listen_wlock(&tcp_hashinfo);
                 lock = &tcp_hashinfo.lhash_lock;
         } else {
                 struct inet_ehash_bucket *head = &tcp_hashinfo.ehash[sk->sk_hashent];
@@ -624,7 +573,7 @@ ok:
                 inet_bind_hash(sk, tb, port);
                 if (sk_unhashed(sk)) {
                         inet_sk(sk)->sport = htons(port);
-                        __tcp_v4_hash(sk, 0);
+                        __inet_hash(&tcp_hashinfo, sk, 0);
                 }
                 spin_unlock(&head->lock);
 
@@ -641,7 +590,7 @@ ok:
         tb  = inet_sk(sk)->bind_hash;
         spin_lock_bh(&head->lock);
         if (sk_head(&tb->owners) == sk && !sk->sk_bind_node.next) {
-                __tcp_v4_hash(sk, 0);
+                __inet_hash(&tcp_hashinfo, sk, 0);
                 spin_unlock_bh(&head->lock);
                 return 0;
         } else {
@@ -1479,7 +1428,7 @@ struct sock *tcp_v4_syn_recv_sock(struct sock *sk, struct sk_buff *skb,
         newtp->advmss = dst_metric(dst, RTAX_ADVMSS);
         tcp_initialize_rcv_mss(newsk);
 
-        __tcp_v4_hash(newsk, 0);
+        __inet_hash(&tcp_hashinfo, newsk, 0);
         __inet_inherit_port(&tcp_hashinfo, sk, newsk);
 
         return newsk;
@@ -2102,12 +2051,12 @@ static void *tcp_get_idx(struct seq_file *seq, loff_t pos)
         void *rc;
         struct tcp_iter_state* st = seq->private;
 
-        tcp_listen_lock();
+        inet_listen_lock(&tcp_hashinfo);
         st->state = TCP_SEQ_STATE_LISTENING;
         rc        = listening_get_idx(seq, &pos);
 
         if (!rc) {
-                tcp_listen_unlock();
+                inet_listen_unlock(&tcp_hashinfo);
                 local_bh_disable();
                 st->state = TCP_SEQ_STATE_ESTABLISHED;
                 rc        = established_get_idx(seq, pos);
@@ -2140,7 +2089,7 @@ static void *tcp_seq_next(struct seq_file *seq, void *v, loff_t *pos)
         case TCP_SEQ_STATE_LISTENING:
                 rc = listening_get_next(seq, v);
                 if (!rc) {
-                        tcp_listen_unlock();
+                        inet_listen_unlock(&tcp_hashinfo);
                         local_bh_disable();
                         st->state = TCP_SEQ_STATE_ESTABLISHED;
                         rc        = established_get_first(seq);
@@ -2168,7 +2117,7 @@ static void tcp_seq_stop(struct seq_file *seq, void *v)
                 }
         case TCP_SEQ_STATE_LISTENING:
                 if (v != SEQ_START_TOKEN)
-                        tcp_listen_unlock();
+                        inet_listen_unlock(&tcp_hashinfo);
                 break;
         case TCP_SEQ_STATE_TIME_WAIT:
         case TCP_SEQ_STATE_ESTABLISHED:
@@ -2431,7 +2380,6 @@ void __init tcp_v4_init(struct net_proto_family *ops)
 EXPORT_SYMBOL(ipv4_specific);
 EXPORT_SYMBOL(inet_bind_bucket_create);
 EXPORT_SYMBOL(tcp_hashinfo);
-EXPORT_SYMBOL(tcp_listen_wlock);
 EXPORT_SYMBOL(tcp_prot);
 EXPORT_SYMBOL(tcp_unhash);
 EXPORT_SYMBOL(tcp_v4_conn_request);