net: Introduce for_each_netdev_rcu() iterator

Adds RCU management to the list of netdevices.

Convert some for_each_netdev() users to RCU version, if
it can avoid read_lock-ing dev_base_lock

Ie:
	read_lock(&dev_base_loack);
	for_each_netdev(net, dev)
		some_action();
	read_unlock(&dev_base_lock);

becomes :

	rcu_read_lock();
	for_each_netdev_rcu(net, dev)
		some_action();
	rcu_read_unlock();


Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet 2009-11-04 05:43:23 -08:00 committed by David S. Miller
parent d0075634cf
commit c6d14c8456
11 changed files with 68 additions and 77 deletions

View file

@ -908,8 +908,8 @@ static int dn_route_output_slow(struct dst_entry **pprt, const struct flowi *old
dev_put(dev_out);
goto out;
}
read_lock(&dev_base_lock);
for_each_netdev(&init_net, dev) {
rcu_read_lock();
for_each_netdev_rcu(&init_net, dev) {
if (!dev->dn_ptr)
continue;
if (!dn_dev_islocal(dev, oldflp->fld_src))
@ -922,7 +922,7 @@ static int dn_route_output_slow(struct dst_entry **pprt, const struct flowi *old
dev_out = dev;
break;
}
read_unlock(&dev_base_lock);
rcu_read_unlock();
if (dev_out == NULL)
goto out;
dev_hold(dev_out);