net: avoid two atomic ops in ip_rcv_options()
in_dev_get() -> __in_dev_get_rcu() in a rcu protected function.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/ip_input.c b/net/ipv4/ip_input.c
index d274078..08a3b12 100644
--- a/net/ipv4/ip_input.c
+++ b/net/ipv4/ip_input.c
@@ -293,18 +293,16 @@
}
if (unlikely(opt->srr)) {
- struct in_device *in_dev = in_dev_get(dev);
+ struct in_device *in_dev = __in_dev_get_rcu(dev);
+
if (in_dev) {
if (!IN_DEV_SOURCE_ROUTE(in_dev)) {
if (IN_DEV_LOG_MARTIANS(in_dev) &&
net_ratelimit())
printk(KERN_INFO "source route option %pI4 -> %pI4\n",
&iph->saddr, &iph->daddr);
- in_dev_put(in_dev);
goto drop;
}
-
- in_dev_put(in_dev);
}
if (ip_options_rcv_srr(skb))