gre: 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, 10 insertions, 5 deletions

diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c
index 40f043915235..a77807d449e3 100644
--- a/net/ipv4/ip_gre.c
+++ b/net/ipv4/ip_gre.c
@@ -1290,16 +1290,19 @@ static const struct net_protocol ipgre_protocol = {
         .netns_ok       =       1,
 };
 
-static void ipgre_destroy_tunnels(struct ipgre_net *ign)
+static void ipgre_destroy_tunnels(struct ipgre_net *ign, struct list_head *head)
 {
         int prio;
 
         for (prio = 0; prio < 4; prio++) {
                 int h;
                 for (h = 0; h < HASH_SIZE; h++) {
-                        struct ip_tunnel *t;
-                        while ((t = ign->tunnels[prio][h]) != NULL)
-                                unregister_netdevice(t->dev);
+                        struct ip_tunnel *t = ign->tunnels[prio][h];
+
+                        while (t != NULL) {
+                                unregister_netdevice_queue(t->dev, head);
+                                t = t->next;
+                        }
                 }
         }
 }
@@ -1347,10 +1350,12 @@ err_alloc:
 static void ipgre_exit_net(struct net *net)
 {
         struct ipgre_net *ign;
+        LIST_HEAD(list);
 
         ign = net_generic(net, ipgre_net_id);
         rtnl_lock();
-        ipgre_destroy_tunnels(ign);
+        ipgre_destroy_tunnels(ign, &list);
+        unregister_netdevice_many(&list);
         rtnl_unlock();
         kfree(ign);
 }