ipv6 sit: Optimize multiple unregistration

Speedup module unloading by factorizing synchronize_rcu() calls

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 11 insertions, 6 deletions

diff --git a/net/ipv6/sit.c b/net/ipv6/sit.c
index b6b16264b305..2362a3397e91 100644
--- a/net/ipv6/sit.c
+++ b/net/ipv6/sit.c
@@ -1145,16 +1145,19 @@ static struct xfrm_tunnel sit_handler = {
         .priority       =       1,
 };
 
-static void sit_destroy_tunnels(struct sit_net *sitn)
+static void sit_destroy_tunnels(struct sit_net *sitn, struct list_head *head)
 {
         int prio;
 
         for (prio = 1; prio < 4; prio++) {
                 int h;
                 for (h = 0; h < HASH_SIZE; h++) {
-                        struct ip_tunnel *t;
-                        while ((t = sitn->tunnels[prio][h]) != NULL)
-                                unregister_netdevice(t->dev);
+                        struct ip_tunnel *t = sitn->tunnels[prio][h];
+
+                        while (t != NULL) {
+                                unregister_netdevice_queue(t->dev, head);
+                                t = t->next;
+                        }
                 }
         }
 }
@@ -1208,11 +1211,13 @@ err_alloc:
 static void sit_exit_net(struct net *net)
 {
         struct sit_net *sitn;
+        LIST_HEAD(list);
 
         sitn = net_generic(net, sit_net_id);
         rtnl_lock();
-        sit_destroy_tunnels(sitn);
-        unregister_netdevice(sitn->fb_tunnel_dev);
+        sit_destroy_tunnels(sitn, &list);
+        unregister_netdevice_queue(sitn->fb_tunnel_dev, &list);
+        unregister_netdevice_many(&list);
         rtnl_unlock();
         kfree(sitn);
 }