[PATCH net] net: vrf: remove redundant vrf neigh entry

[linmiaohe]

From: Miaohe Lin <linmiaohe@xxxxxxxxxx>

When vrf->rth is created, it wouldn't change in his lifetime.And in
func vrf_finish_output, we always create a neigh with ip_hdr(skb)->daddr
as key because rth->rt_gateway is equal to 0. But I think we only need
one vrf neigh entry because we strip the ethernet header and reset the
dst_entry in vrf_process_v4_outbound.
So I set rth->rt_gateway to loopback addr(It's ok to set any other
valid ip address, just choose one.). And we would only create one vrf
neigh entry. This helps saving some memory and improving the hitting
rate of neigh lookup.
If there is something I misunderstand, it's very nice of you to
let me know. Thanks a lot.

Signed-off-by: linmiaohe <linmiaohe@xxxxxxxxxx>
---
 drivers/net/vrf.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/net/vrf.c b/drivers/net/vrf.c
index 7c1430ed0244..2b0227fb8f53 100644
--- a/drivers/net/vrf.c
+++ b/drivers/net/vrf.c
@@ -738,6 +738,7 @@ static int vrf_rtable_create(struct net_device *dev)
 		return -ENOMEM;

 	rth->dst.output	= vrf_output;
+	rth->rt_gateway = htonl(INADDR_LOOPBACK);

 	rcu_assign_pointer(vrf->rth, rth);

-- 
2.16.2