ipv6: RCU changes in ipv6_get_mtu() and ip6_dst_hoplimit()
Use RCU to avoid atomic ops on idev refcnt in ipv6_get_mtu()
and ip6_dst_hoplimit()
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index f770285..8f2d040 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -1084,11 +1084,11 @@
int mtu = IPV6_MIN_MTU;
struct inet6_dev *idev;
- idev = in6_dev_get(dev);
- if (idev) {
+ rcu_read_lock();
+ idev = __in6_dev_get(dev);
+ if (idev)
mtu = idev->cnf.mtu6;
- in6_dev_put(idev);
- }
+ rcu_read_unlock();
return mtu;
}
@@ -1097,12 +1097,15 @@
int hoplimit = dst_metric(dst, RTAX_HOPLIMIT);
if (hoplimit < 0) {
struct net_device *dev = dst->dev;
- struct inet6_dev *idev = in6_dev_get(dev);
- if (idev) {
+ struct inet6_dev *idev;
+
+ rcu_read_lock();
+ idev = __in6_dev_get(dev);
+ if (idev)
hoplimit = idev->cnf.hop_limit;
- in6_dev_put(idev);
- } else
+ else
hoplimit = dev_net(dev)->ipv6.devconf_all->hop_limit;
+ rcu_read_unlock();
}
return hoplimit;
}