 */
static void netdev_wait_allrefs(struct net_device *dev)
{
	unsigned long rebroadcast_time, warning_time;
	int refcnt;

	linkwatch_forget_dev(dev);

	rebroadcast_time = warning_time = jiffies;
	refcnt = netdev_refcnt_read(dev);

	while (refcnt != 0) {
		if (time_after(jiffies, rebroadcast_time + 1 * HZ)) {
			rtnl_lock();

			/* Rebroadcast unregister notification */
			call_netdevice_notifiers(NETDEV_UNREGISTER, dev);

			__rtnl_unlock();
			rcu_barrier();
			rtnl_lock();

			call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev);
			if (test_bit(__LINK_STATE_LINKWATCH_PENDING,
				     &dev->state)) {
				/* We must not have linkwatch events
				 * pending on unregister. If this
				 * happens, we simply run the queue
				 * unscheduled, resulting in a noop
				 * for this device.
				 */
				linkwatch_run_queue();
			}

			__rtnl_unlock();

			rebroadcast_time = jiffies;
		}

		msleep(250);

		refcnt = netdev_refcnt_read(dev);

		if (time_after(jiffies, warning_time + 10 * HZ)) {
			pr_emerg("unregister_netdevice: waiting for %s to become free. Usage count = %d\n",
				 dev->name, refcnt);
			warning_time = jiffies;
		}
	}
 */
static void netdev_wait_allrefs(struct net_device *dev)
{
	unsigned long rebroadcast_time, warning_time;
	int refcnt;

	linkwatch_forget_dev(dev);

	rebroadcast_time = warning_time = jiffies;
	refcnt = netdev_refcnt_read(dev);

	while (refcnt != 0) {
		if (time_after(jiffies, rebroadcast_time + 1 * HZ)) {
			rtnl_lock();

			 
			call_netdevice_notifiers(NETDEV_UNREGISTER, dev);

			__rtnl_unlock();
			rcu_barrier();
			rtnl_lock();

			call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev);
			if (test_bit(__LINK_STATE_LINKWATCH_PENDING,
				     &dev->state)) {
				 
				linkwatch_run_queue();
			}

			__rtnl_unlock();

			rebroadcast_time = jiffies;
		}

		msleep(250);

		refcnt = netdev_refcnt_read(dev);

		if (time_after(jiffies, warning_time + 10 * HZ)) {
			pr_emerg("unregister_netdevice: waiting for %s to become free. Usage count = %d\n",
				 dev->name, refcnt);
			warning_time = jiffies;
		}
	}