Commit 8a4fc54b authored by Eric Dumazet's avatar Eric Dumazet Committed by David S. Miller
Browse files

net: get rid of rtnl_lock_unregistering() 



After recent patches, and in particular commits
 faab39f6 ("net: allow out-of-order netdev unregistration") and
 e5f80fcf ("ipv6: give an IPv6 dev to blackhole_netdev")
we no longer need the barrier implemented in rtnl_lock_unregistering().

Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent b3ae2d35

net/core/dev.c

+0 −42
Original line number Diff line number Diff line
@@ -10884,36 +10884,6 @@ static void __net_exit default_device_exit_net(struct net *net) 
	}

}



static void __net_exit rtnl_lock_unregistering(struct list_head *net_list)

{

	/* Return (with the rtnl_lock held) when there are no network

	 * devices unregistering in any network namespace in net_list.

	 */

	DEFINE_WAIT_FUNC(wait, woken_wake_function);

	bool unregistering;

	struct net *net;



	ASSERT_RTNL();

	add_wait_queue(&netdev_unregistering_wq, &wait);

	for (;;) {

		unregistering = false;



		list_for_each_entry(net, net_list, exit_list) {

			if (atomic_read(&net->dev_unreg_count) > 0) {

				unregistering = true;

				break;

			}

		}

		if (!unregistering)

			break;

		__rtnl_unlock();



		wait_woken(&wait, TASK_UNINTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT);

		rtnl_lock();

	}

	remove_wait_queue(&netdev_unregistering_wq, &wait);

}



static void __net_exit default_device_exit_batch(struct list_head *net_list)

{

	/* At exit all network devices most be removed from a network
@@ -10930,18 +10900,6 @@ static void __net_exit default_device_exit_batch(struct list_head *net_list) 
		default_device_exit_net(net);

		cond_resched();

	}

	/* To prevent network device cleanup code from dereferencing

	 * loopback devices or network devices that have been freed

	 * wait here for all pending unregistrations to complete,

	 * before unregistring the loopback device and allowing the

	 * network namespace be freed.

	 *

	 * The netdev todo list containing all network devices

	 * unregistrations that happen in default_device_exit_batch

	 * will run in the rtnl_unlock() at the end of

	 * default_device_exit_batch.

	 */

	rtnl_lock_unregistering(net_list);



	list_for_each_entry(net, net_list, exit_list) {

		for_each_netdev_reverse(net, dev) {