Commit 44f4d5a2 authored by Rémi Denis-Courmont's avatar Rémi Denis-Courmont Committed by David S. Miller
Browse files

Phonet: convert bound sockets hash list to RCU 



This gets rid of the last spinlock in the Phonet stack proper.

Signed-off-by: default avatarRémi Denis-Courmont <remi.denis-courmont@nokia.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent fce55922

net/phonet/socket.c

+21 −24
Original line number Diff line number Diff line
@@ -52,7 +52,7 @@ static int pn_socket_release(struct socket *sock) 


static struct  {

	struct hlist_head hlist[PN_HASHSIZE];

	spinlock_t lock;

	struct mutex lock;

} pnsocks;



void __init pn_sock_init(void)
@@ -61,7 +61,7 @@ void __init pn_sock_init(void) 


	for (i = 0; i < PN_HASHSIZE; i++)

		INIT_HLIST_HEAD(pnsocks.hlist + i);

	spin_lock_init(&pnsocks.lock);

	mutex_init(&pnsocks.lock);

}



static struct hlist_head *pn_hash_list(u16 obj)
@@ -82,9 +82,8 @@ struct sock *pn_find_sock_by_sa(struct net *net, const struct sockaddr_pn *spn) 
	u8 res = spn->spn_resource;

	struct hlist_head *hlist = pn_hash_list(obj);



	spin_lock_bh(&pnsocks.lock);



	sk_for_each(sknode, node, hlist) {

	rcu_read_lock();

	sk_for_each_rcu(sknode, node, hlist) {

		struct pn_sock *pn = pn_sk(sknode);

		BUG_ON(!pn->sobject); /* unbound socket */
@@ -107,8 +106,7 @@ struct sock *pn_find_sock_by_sa(struct net *net, const struct sockaddr_pn *spn) 
		sock_hold(sknode);

		break;

	}



	spin_unlock_bh(&pnsocks.lock);

	rcu_read_unlock();



	return rval;

}
@@ -119,7 +117,7 @@ void pn_deliver_sock_broadcast(struct net *net, struct sk_buff *skb) 
	struct hlist_head *hlist = pnsocks.hlist;

	unsigned h;



	spin_lock(&pnsocks.lock);

	rcu_read_lock();

	for (h = 0; h < PN_HASHSIZE; h++) {

		struct hlist_node *node;

		struct sock *sknode;
@@ -140,25 +138,26 @@ void pn_deliver_sock_broadcast(struct net *net, struct sk_buff *skb) 
		}

		hlist++;

	}

	spin_unlock(&pnsocks.lock);

	rcu_read_unlock();

}



void pn_sock_hash(struct sock *sk)

{

	struct hlist_head *hlist = pn_hash_list(pn_sk(sk)->sobject);



	spin_lock_bh(&pnsocks.lock);

	sk_add_node(sk, hlist);

	spin_unlock_bh(&pnsocks.lock);

	mutex_lock(&pnsocks.lock);

	sk_add_node_rcu(sk, hlist);

	mutex_unlock(&pnsocks.lock);

}

EXPORT_SYMBOL(pn_sock_hash);



void pn_sock_unhash(struct sock *sk)

{

	spin_lock_bh(&pnsocks.lock);

	sk_del_node_init(sk);

	spin_unlock_bh(&pnsocks.lock);

	mutex_lock(&pnsocks.lock);

	sk_del_node_init_rcu(sk);

	mutex_unlock(&pnsocks.lock);

	pn_sock_unbind_all_res(sk);

	synchronize_rcu();

}

EXPORT_SYMBOL(pn_sock_unhash);
@@ -548,7 +547,7 @@ static struct sock *pn_sock_get_idx(struct seq_file *seq, loff_t pos) 
	unsigned h;



	for (h = 0; h < PN_HASHSIZE; h++) {

		sk_for_each(sknode, node, hlist) {

		sk_for_each_rcu(sknode, node, hlist) {

			if (!net_eq(net, sock_net(sknode)))

				continue;

			if (!pos)
@@ -572,9 +571,9 @@ static struct sock *pn_sock_get_next(struct seq_file *seq, struct sock *sk) 
}



static void *pn_sock_seq_start(struct seq_file *seq, loff_t *pos)

	__acquires(pnsocks.lock)

	__acquires(rcu)

{

	spin_lock_bh(&pnsocks.lock);

	rcu_read_lock();

	return *pos ? pn_sock_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;

}
@@ -591,9 +590,9 @@ static void *pn_sock_seq_next(struct seq_file *seq, void *v, loff_t *pos) 
}



static void pn_sock_seq_stop(struct seq_file *seq, void *v)

	__releases(pnsocks.lock)

	__releases(rcu)

{

	spin_unlock_bh(&pnsocks.lock);

	rcu_read_unlock();

}



static int pn_sock_seq_show(struct seq_file *seq, void *v)
@@ -721,13 +720,11 @@ void pn_sock_unbind_all_res(struct sock *sk) 
	}

	mutex_unlock(&resource_mutex);



	if (match == 0)

		return;

	synchronize_rcu();

	while (match > 0) {

		sock_put(sk);

		__sock_put(sk);

		match--;

	}

	/* Caller is responsible for RCU sync before final sock_put() */

}



#ifdef CONFIG_PROC_FS