net: Simplfy default_device_exit and improve batching.

- Defer dellink to net_cleanup() allowing for batching.
- Fix comment.
- Use for_each_netdev_safe again as dev_change_net_namespace touches
  at most one network device (unlike veth dellink).

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/core/dev.c b/net/core/dev.c
index bb37ee1..e3e18de 100644 (file)
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -5736,14 +5736,13 @@ static struct pernet_operations __net_initdata netdev_net_ops = {
 
 static void __net_exit default_device_exit(struct net *net)
 {
-       struct net_device *dev;
+       struct net_device *dev, *aux;
        /*
-        * Push all migratable of the network devices back to the
+        * Push all migratable network devices back to the
         * initial network namespace
         */
        rtnl_lock();
-restart:
-       for_each_netdev(net, dev) {
+       for_each_netdev_safe(net, dev, aux) {
                int err;
                char fb_name[IFNAMSIZ];
 
@@ -5751,11 +5750,9 @@ restart:
                if (dev->features & NETIF_F_NETNS_LOCAL)
                        continue;
 
-               /* Delete virtual devices */
-               if (dev->rtnl_link_ops && dev->rtnl_link_ops->dellink) {
-                       dev->rtnl_link_ops->dellink(dev, NULL);
-                       goto restart;
-               }
+               /* Leave virtual devices for the generic cleanup */
+               if (dev->rtnl_link_ops)
+                       continue;
 
                /* Push remaing network devices to init_net */
                snprintf(fb_name, IFNAMSIZ, "dev%d", dev->ifindex);
@@ -5765,7 +5762,6 @@ restart:
                                __func__, dev->name, err);
                        BUG();
                }
-               goto restart;
        }
        rtnl_unlock();
 }