net: Move network device exit batching

Move network device exit batching from a special case in
net_namespace.c to using common mechanisms in dev.c

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

2 files changed, 25 insertions, 24 deletions

diff --git a/net/core/dev.c b/net/core/dev.c
index e3e18dee0bd3..0913a08a87d6 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -5766,8 +5766,33 @@ static void __net_exit default_device_exit(struct net *net)
         rtnl_unlock();
 }
 
+static void __net_exit default_device_exit_batch(struct list_head *net_list)
+{
+        /* At exit all network devices most be removed from a network
+         * namespace.  Do this in the reverse order of registeration.
+         * Do this across as many network namespaces as possible to
+         * improve batching efficiency.
+         */
+        struct net_device *dev;
+        struct net *net;
+        LIST_HEAD(dev_kill_list);
+
+        rtnl_lock();
+        list_for_each_entry(net, net_list, exit_list) {
+                for_each_netdev_reverse(net, dev) {
+                        if (dev->rtnl_link_ops)
+                                dev->rtnl_link_ops->dellink(dev, &dev_kill_list);
+                        else
+                                unregister_netdevice_queue(dev, &dev_kill_list);
+                }
+        }
+        unregister_netdevice_many(&dev_kill_list);
+        rtnl_unlock();
+}
+
 static struct pernet_operations __net_initdata default_device_ops = {
         .exit = default_device_exit,
+        .exit_batch = default_device_exit_batch,
 };
 
 /*
diff --git a/net/core/net_namespace.c b/net/core/net_namespace.c
index 6c7f6e04dbbf..4026a4cff93c 100644
--- a/net/core/net_namespace.c
+++ b/net/core/net_namespace.c
@@ -8,10 +8,8 @@
 #include <linux/idr.h>
 #include <linux/rculist.h>
 #include <linux/nsproxy.h>
-#include <linux/netdevice.h>
 #include <net/net_namespace.h>
 #include <net/netns/generic.h>
-#include <net/rtnetlink.h>
 
 /*
  *      Our network namespace constructor/destructor lists
@@ -29,20 +27,6 @@ EXPORT_SYMBOL(init_net);
 
 #define INITIAL_NET_GEN_PTRS    13 /* +1 for len +2 for rcu_head */
 
-static void unregister_netdevices(struct net *net, struct list_head *list)
-{
-        struct net_device *dev;
-        /* At exit all network devices most be removed from a network
-         * namespace.  Do this in the reverse order of registeration.
-         */
-        for_each_netdev_reverse(net, dev) {
-                if (dev->rtnl_link_ops)
-                        dev->rtnl_link_ops->dellink(dev, list);
-                else
-                        unregister_netdevice_queue(dev, list);
-        }
-}
-
 static int ops_init(const struct pernet_operations *ops, struct net *net)
 {
         int err;
@@ -78,14 +62,6 @@ static void ops_exit_list(const struct pernet_operations *ops,
                 list_for_each_entry(net, net_exit_list, exit_list)
                         ops->exit(net);
         }
-        if (&ops->list == first_device) {
-                LIST_HEAD(dev_kill_list);
-                rtnl_lock();
-                list_for_each_entry(net, net_exit_list, exit_list)
-                        unregister_netdevices(net, &dev_kill_list);
-                unregister_netdevice_many(&dev_kill_list);
-                rtnl_unlock();
-        }
         if (ops->exit_batch)
                 ops->exit_batch(net_exit_list);
 }