Commit 5c578aed authored by stephen hemminger's avatar stephen hemminger Committed by David S. Miller
Browse files

IPv6: convert addrconf hash list to RCU 



Convert from reader/writer lock to RCU and spinlock for addrconf
hash list.

Adds an additional helper macro for hlist_for_each_entry_continue_rcu
to handle the continue case.

Signed-off-by: default avatarStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent c2e21293

include/linux/rculist.h

+13 −0
Original line number Diff line number Diff line
@@ -428,5 +428,18 @@ static inline void hlist_add_after_rcu(struct hlist_node *prev, 
		({ tpos = hlist_entry(pos, typeof(*tpos), member); 1; }); \

		pos = rcu_dereference_raw(pos->next))



/**

 * hlist_for_each_entry_continue_rcu - iterate over a hlist continuing after current point

 * @tpos:	the type * to use as a loop cursor.

 * @pos:	the &struct hlist_node to use as a loop cursor.

 * @member:	the name of the hlist_node within the struct.

 */

#define hlist_for_each_entry_continue_rcu(tpos, pos, member)		\

	for (pos = rcu_dereference((pos)->next);			\

	     pos && ({ prefetch(pos->next); 1; }) &&			\

	     ({ tpos = hlist_entry(pos, typeof(*tpos), member); 1; });  \

	     pos = rcu_dereference(pos->next))





#endif	/* __KERNEL__ */

#endif

include/net/if_inet6.h

+1 −0
Original line number Diff line number Diff line
@@ -64,6 +64,7 @@ struct inet6_ifaddr { 
#endif



	int			dead;

	struct rcu_head		rcu;

};



struct ip6_sf_socklist {

net/ipv6/addrconf.c

+44 −41
Original line number Diff line number Diff line
@@ -127,7 +127,7 @@ static int ipv6_count_addresses(struct inet6_dev *idev); 
 *	Configured unicast address hash table

 */

static struct hlist_head inet6_addr_lst[IN6_ADDR_HSIZE];

static DEFINE_RWLOCK(addrconf_hash_lock);

static DEFINE_SPINLOCK(addrconf_hash_lock);



static void addrconf_verify(unsigned long);
@@ -523,8 +523,13 @@ static int addrconf_fixup_forwarding(struct ctl_table *table, int *p, int old) 
}

#endif



/* Nobody refers to this ifaddr, destroy it */

static void inet6_ifa_finish_destroy_rcu(struct rcu_head *head)

{

	struct inet6_ifaddr *ifp = container_of(head, struct inet6_ifaddr, rcu);

	kfree(ifp);

}



/* Nobody refers to this ifaddr, destroy it */

void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp)

{

	WARN_ON(ifp->if_next != NULL);
@@ -545,7 +550,7 @@ void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp) 
	}

	dst_release(&ifp->rt->u.dst);



	kfree(ifp);

	call_rcu(&ifp->rcu, inet6_ifa_finish_destroy_rcu);

}



static void
@@ -616,7 +621,7 @@ ipv6_add_addr(struct inet6_dev *idev, const struct in6_addr *addr, int pfxlen, 
		goto out2;

	}



	write_lock(&addrconf_hash_lock);

	spin_lock(&addrconf_hash_lock);



	/* Ignore adding duplicate addresses on an interface */

	if (ipv6_chk_same_addr(dev_net(idev->dev), addr, idev->dev)) {
@@ -670,9 +675,9 @@ ipv6_add_addr(struct inet6_dev *idev, const struct in6_addr *addr, int pfxlen, 
	/* Add to big hash table */

	hash = ipv6_addr_hash(addr);



	hlist_add_head(&ifa->addr_lst, &inet6_addr_lst[hash]);

	hlist_add_head_rcu(&ifa->addr_lst, &inet6_addr_lst[hash]);

	in6_ifa_hold(ifa);

	write_unlock(&addrconf_hash_lock);

	spin_unlock(&addrconf_hash_lock);



	write_lock(&idev->lock);

	/* Add to inet6_dev unicast addr list. */
@@ -699,7 +704,7 @@ ipv6_add_addr(struct inet6_dev *idev, const struct in6_addr *addr, int pfxlen, 


	return ifa;

out:

	write_unlock(&addrconf_hash_lock);

	spin_unlock(&addrconf_hash_lock);

	goto out2;

}
@@ -717,10 +722,10 @@ static void ipv6_del_addr(struct inet6_ifaddr *ifp) 


	ifp->dead = 1;



	write_lock_bh(&addrconf_hash_lock);

	hlist_del_init(&ifp->addr_lst);

	spin_lock_bh(&addrconf_hash_lock);

	hlist_del_init_rcu(&ifp->addr_lst);

	__in6_ifa_put(ifp);

	write_unlock_bh(&addrconf_hash_lock);

	spin_unlock_bh(&addrconf_hash_lock);



	write_lock_bh(&idev->lock);

#ifdef CONFIG_IPV6_PRIVACY
@@ -1274,8 +1279,8 @@ int ipv6_chk_addr(struct net *net, struct in6_addr *addr, 
	struct hlist_node *node;

	u8 hash = ipv6_addr_hash(addr);



	read_lock_bh(&addrconf_hash_lock);

	hlist_for_each_entry(ifp, node, &inet6_addr_lst[hash], addr_lst) {

	rcu_read_lock_bh();

	hlist_for_each_entry_rcu(ifp, node, &inet6_addr_lst[hash], addr_lst) {

		if (!net_eq(dev_net(ifp->idev->dev), net))

			continue;

		if (ipv6_addr_equal(&ifp->addr, addr) &&
@@ -1285,7 +1290,8 @@ int ipv6_chk_addr(struct net *net, struct in6_addr *addr, 
				break;

		}

	}

	read_unlock_bh(&addrconf_hash_lock);

	rcu_read_unlock_bh();



	return ifp != NULL;

}

EXPORT_SYMBOL(ipv6_chk_addr);
@@ -1341,8 +1347,8 @@ struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr *add 
	struct hlist_node *node;

	u8 hash = ipv6_addr_hash(addr);



	read_lock_bh(&addrconf_hash_lock);

	hlist_for_each_entry(ifp, node, &inet6_addr_lst[hash], addr_lst) {

	rcu_read_lock_bh();

	hlist_for_each_entry_rcu(ifp, node, &inet6_addr_lst[hash], addr_lst) {

		if (!net_eq(dev_net(ifp->idev->dev), net))

			continue;

		if (ipv6_addr_equal(&ifp->addr, addr)) {
@@ -1353,7 +1359,7 @@ struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr *add 
			}

		}

	}

	read_unlock_bh(&addrconf_hash_lock);

	rcu_read_unlock_bh();



	return ifp;

}
@@ -2698,10 +2704,10 @@ static int addrconf_ifdown(struct net_device *dev, int how) 
		write_unlock_bh(&idev->lock);



		/* clear hash table */

		write_lock_bh(&addrconf_hash_lock);

		hlist_del_init(&ifa->addr_lst);

		spin_lock_bh(&addrconf_hash_lock);

		hlist_del_init_rcu(&ifa->addr_lst);

		__in6_ifa_put(ifa);

		write_unlock_bh(&addrconf_hash_lock);

		spin_unlock_bh(&addrconf_hash_lock);



		__ipv6_ifa_notify(RTM_DELADDR, ifa);

		atomic_notifier_call_chain(&inet6addr_chain, NETDEV_DOWN, ifa);
@@ -2946,12 +2952,11 @@ static struct inet6_ifaddr *if6_get_first(struct seq_file *seq) 


	for (state->bucket = 0; state->bucket < IN6_ADDR_HSIZE; ++state->bucket) {

		struct hlist_node *n;

		hlist_for_each_entry(ifa, n,

				     &inet6_addr_lst[state->bucket], addr_lst) {

		hlist_for_each_entry_rcu(ifa, n, &inet6_addr_lst[state->bucket],

					 addr_lst)

			if (net_eq(dev_net(ifa->idev->dev), net))

				return ifa;

	}

	}

	return NULL;

}
@@ -2962,10 +2967,9 @@ static struct inet6_ifaddr *if6_get_next(struct seq_file *seq, 
	struct net *net = seq_file_net(seq);

	struct hlist_node *n = &ifa->addr_lst;



	hlist_for_each_entry_continue(ifa, n, addr_lst) {

	hlist_for_each_entry_continue_rcu(ifa, n, addr_lst)

		if (net_eq(dev_net(ifa->idev->dev), net))

			return ifa;

	}



	while (++state->bucket < IN6_ADDR_HSIZE) {

		hlist_for_each_entry(ifa, n,
@@ -2989,9 +2993,9 @@ static struct inet6_ifaddr *if6_get_idx(struct seq_file *seq, loff_t pos) 
}



static void *if6_seq_start(struct seq_file *seq, loff_t *pos)

	__acquires(addrconf_hash_lock)

	__acquires(rcu)

{

	read_lock_bh(&addrconf_hash_lock);

	rcu_read_lock_bh();

	return if6_get_idx(seq, *pos);

}
@@ -3005,9 +3009,9 @@ static void *if6_seq_next(struct seq_file *seq, void *v, loff_t *pos) 
}



static void if6_seq_stop(struct seq_file *seq, void *v)

	__releases(addrconf_hash_lock)

	__releases(rcu)

{

	read_unlock_bh(&addrconf_hash_lock);

	rcu_read_unlock_bh();

}



static int if6_seq_show(struct seq_file *seq, void *v)
@@ -3081,8 +3085,8 @@ int ipv6_chk_home_addr(struct net *net, struct in6_addr *addr) 
	struct hlist_node *n;

	u8 hash = ipv6_addr_hash(addr);



	read_lock_bh(&addrconf_hash_lock);

	hlist_for_each_entry(ifp, n, &inet6_addr_lst[hash], addr_lst) {

	rcu_read_lock_bh();

	hlist_for_each_entry_rcu(ifp, n, &inet6_addr_lst[hash], addr_lst) {

		if (!net_eq(dev_net(ifp->idev->dev), net))

			continue;

		if (ipv6_addr_equal(&ifp->addr, addr) &&
@@ -3091,7 +3095,7 @@ int ipv6_chk_home_addr(struct net *net, struct in6_addr *addr) 
			break;

		}

	}

	read_unlock_bh(&addrconf_hash_lock);

	rcu_read_unlock_bh();

	return ret;

}

#endif
@@ -3107,7 +3111,8 @@ static void addrconf_verify(unsigned long foo) 
	unsigned long now, next;

	int i;



	spin_lock_bh(&addrconf_verify_lock);

	rcu_read_lock_bh();

	spin_lock(&addrconf_verify_lock);

	now = jiffies;

	next = now + ADDR_CHECK_FREQUENCY;
@@ -3116,8 +3121,8 @@ static void addrconf_verify(unsigned long foo) 
	for (i=0; i < IN6_ADDR_HSIZE; i++) {



restart:

		read_lock(&addrconf_hash_lock);

		hlist_for_each_entry(ifp, node, &inet6_addr_lst[i], addr_lst) {

		hlist_for_each_entry_rcu(ifp, node,

					 &inet6_addr_lst[i], addr_lst) {

			unsigned long age;

#ifdef CONFIG_IPV6_PRIVACY

			unsigned long regen_advance;
@@ -3139,7 +3144,6 @@ static void addrconf_verify(unsigned long foo) 
			    age >= ifp->valid_lft) {

				spin_unlock(&ifp->lock);

				in6_ifa_hold(ifp);

				read_unlock(&addrconf_hash_lock);

				ipv6_del_addr(ifp);

				goto restart;

			} else if (ifp->prefered_lft == INFINITY_LIFE_TIME) {
@@ -3161,7 +3165,6 @@ static void addrconf_verify(unsigned long foo) 


				if (deprecate) {

					in6_ifa_hold(ifp);

					read_unlock(&addrconf_hash_lock);



					ipv6_ifa_notify(0, ifp);

					in6_ifa_put(ifp);
@@ -3179,7 +3182,7 @@ static void addrconf_verify(unsigned long foo) 
						in6_ifa_hold(ifp);

						in6_ifa_hold(ifpub);

						spin_unlock(&ifp->lock);

						read_unlock(&addrconf_hash_lock);



						spin_lock(&ifpub->lock);

						ifpub->regen_count = 0;

						spin_unlock(&ifpub->lock);
@@ -3199,12 +3202,12 @@ static void addrconf_verify(unsigned long foo) 
				spin_unlock(&ifp->lock);

			}

		}

		read_unlock(&addrconf_hash_lock);

	}



	addr_chk_timer.expires = time_before(next, jiffies + HZ) ? jiffies + HZ : next;

	add_timer(&addr_chk_timer);

	spin_unlock_bh(&addrconf_verify_lock);

	spin_unlock(&addrconf_verify_lock);

	rcu_read_unlock_bh();

}



static struct in6_addr *extract_addr(struct nlattr *addr, struct nlattr *local)
@@ -4621,10 +4624,10 @@ void addrconf_cleanup(void) 
	/*

	 *	Check hash table.

	 */

	write_lock_bh(&addrconf_hash_lock);

	spin_lock_bh(&addrconf_hash_lock);

	for (i = 0; i < IN6_ADDR_HSIZE; i++)

		WARN_ON(!hlist_empty(&inet6_addr_lst[i]));

	write_unlock_bh(&addrconf_hash_lock);

	spin_unlock_bh(&addrconf_hash_lock);



	del_timer(&addr_chk_timer);

	rtnl_unlock();