net: Remove spinlock from get_net_ns_by_id()

idr_find() is safe under rcu_read_lock() and
maybe_get_net() guarantees that net is alive.

Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/core/net_namespace.c b/net/core/net_namespace.c
index 3c77d84..1ccb953 100644 (file)
--- a/net/core/net_namespace.c
+++ b/net/core/net_namespace.c
@@ -273,11 +273,9 @@ struct net *get_net_ns_by_id(struct net *net, int id)
                return NULL;
 
        rcu_read_lock();
-       spin_lock_bh(&net->nsid_lock);
        peer = idr_find(&net->netns_ids, id);
        if (peer)
                peer = maybe_get_net(peer);
-       spin_unlock_bh(&net->nsid_lock);
        rcu_read_unlock();
 
        return peer;