net: Introduce for_each_netdev_rcu() iterator
Adds RCU management to the list of netdevices.
Convert some for_each_netdev() users to RCU version, if
it can avoid read_lock-ing dev_base_lock
Ie:
read_lock(&dev_base_loack);
for_each_netdev(net, dev)
some_action();
read_unlock(&dev_base_lock);
becomes :
rcu_read_lock();
for_each_netdev_rcu(net, dev)
some_action();
rcu_read_unlock();
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/decnet/af_decnet.c b/net/decnet/af_decnet.c
index 664965c..2e35584 100644
--- a/net/decnet/af_decnet.c
+++ b/net/decnet/af_decnet.c
@@ -749,9 +749,9 @@
if (!(saddr->sdn_flags & SDF_WILD)) {
if (le16_to_cpu(saddr->sdn_nodeaddrl)) {
- read_lock(&dev_base_lock);
+ rcu_read_lock();
ldev = NULL;
- for_each_netdev(&init_net, dev) {
+ for_each_netdev_rcu(&init_net, dev) {
if (!dev->dn_ptr)
continue;
if (dn_dev_islocal(dev, dn_saddr2dn(saddr))) {
@@ -759,7 +759,7 @@
break;
}
}
- read_unlock(&dev_base_lock);
+ rcu_read_unlock();
if (ldev == NULL)
return -EADDRNOTAVAIL;
}