[PATCH net-next 1/2] vxlan: speedup vxlan tunnels dismantle

[Haishuang Yan]

Since we now hold RTNL lock in vxlan_exit_net, it's better to batch them
to speedup vxlan tunnels dismantle.

Signed-off-by: Haishuang Yan <yanhaishu...@cmss.chinamobile.com>
---
 drivers/net/vxlan.c | 26 +++++++++++++++++---------
 1 file changed, 17 insertions(+), 9 deletions(-)

diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c
index 19b9cc5..48a0dc2 100644
--- a/drivers/net/vxlan.c
+++ b/drivers/net/vxlan.c
@@ -3692,18 +3692,16 @@ static __net_init int vxlan_init_net(struct net *net)
        return 0;
 }
 
-static void __net_exit vxlan_exit_net(struct net *net)
+static void vxlan_destroy_tunnels(struct net *net, struct list_head *head)
 {
        struct vxlan_net *vn = net_generic(net, vxlan_net_id);
        struct vxlan_dev *vxlan, *next;
        struct net_device *dev, *aux;
        unsigned int h;
-       LIST_HEAD(list);
 
-       rtnl_lock();
        for_each_netdev_safe(net, dev, aux)
                if (dev->rtnl_link_ops == &vxlan_link_ops)
-                       unregister_netdevice_queue(dev, &list);
+                       unregister_netdevice_queue(dev, head);
 
        list_for_each_entry_safe(vxlan, next, &vn->vxlan_list, next) {
                /* If vxlan->dev is in the same netns, it has already been added
@@ -3711,20 +3709,30 @@ static void __net_exit vxlan_exit_net(struct net *net)
                 */
                if (!net_eq(dev_net(vxlan->dev), net)) {
                        gro_cells_destroy(&vxlan->gro_cells);
-                       unregister_netdevice_queue(vxlan->dev, &list);
+                       unregister_netdevice_queue(vxlan->dev, head);
                }
        }
 
-       unregister_netdevice_many(&list);
-       rtnl_unlock();
-
        for (h = 0; h < PORT_HASH_SIZE; ++h)
                WARN_ON_ONCE(!hlist_empty(&vn->sock_list[h]));
 }
 
+static void __net_exit vxlan_exit_batch_net(struct list_head *net_list)
+{
+       struct net *net;
+       LIST_HEAD(list);
+
+       rtnl_lock();
+       list_for_each_entry(net, net_list, exit_list)
+               vxlan_destroy_tunnels(net, &list);
+
+       unregister_netdevice_many(&list);
+       rtnl_unlock();
+}
+
 static struct pernet_operations vxlan_net_ops = {
        .init = vxlan_init_net,
-       .exit = vxlan_exit_net,
+       .exit_batch = vxlan_exit_batch_net,
        .id   = &vxlan_net_id,
        .size = sizeof(struct vxlan_net),
 };
-- 
1.8.3.1