Commit 47360228 authored by Eric Dumazet's avatar Eric Dumazet Committed by David S. Miller
Browse files

ipv4: RCU changes in __mkroute_input() 



Avoid two atomic ops on output device refcount

Signed-off-by: default avatarEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent bc10502d

net/ipv4/route.c

+3 −5
Original line number Diff line number Diff line
@@ -1957,22 +1957,22 @@ static void ip_handle_martian_source(struct net_device *dev, 
#endif

}



/* called in rcu_read_lock() section */

static int __mkroute_input(struct sk_buff *skb,

			   struct fib_result *res,

			   struct in_device *in_dev,

			   __be32 daddr, __be32 saddr, u32 tos,

			   struct rtable **result)

{



	struct rtable *rth;

	int err;

	struct in_device *out_dev;

	unsigned flags = 0;

	unsigned int flags = 0;

	__be32 spec_dst;

	u32 itag;



	/* get a working reference to the output device */

	out_dev = in_dev_get(FIB_RES_DEV(*res));

	out_dev = __in_dev_get_rcu(FIB_RES_DEV(*res));

	if (out_dev == NULL) {

		if (net_ratelimit())

			printk(KERN_CRIT "Bug in ip_route_input" \
@@ -2053,8 +2053,6 @@ static int __mkroute_input(struct sk_buff *skb, 
	*result = rth;

	err = 0;

 cleanup:

	/* release the working reference to the output device */

	in_dev_put(out_dev);

	return err;

}