ipv4: Fix input route performance regression.

With the routing cache removal we lost the "noref" code paths on
input, and this can kill some routing workloads.

Reinstate the noref path when we hit a cached route in the FIB
nexthops.

With help from Eric Dumazet.

Reported-by: Alexander Duyck <alexander.duyck@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 2 insertions, 2 deletions

diff --git a/net/ipv4/xfrm4_input.c b/net/ipv4/xfrm4_input.c
index 58d23a572509..06814b6216dc 100644
--- a/net/ipv4/xfrm4_input.c
+++ b/net/ipv4/xfrm4_input.c
@@ -27,8 +27,8 @@ static inline int xfrm4_rcv_encap_finish(struct sk_buff *skb)
         if (skb_dst(skb) == NULL) {
                 const struct iphdr *iph = ip_hdr(skb);
 
-                if (ip_route_input(skb, iph->daddr, iph->saddr,
-                                   iph->tos, skb->dev))
+                if (ip_route_input_noref(skb, iph->daddr, iph->saddr,
+                                         iph->tos, skb->dev))
                         goto drop;
         }
         return dst_input(skb);