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/ip_input.c b/net/ipv4/ip_input.c
index 93134b0eab0c..bda8cac2ae91 100644
--- a/net/ipv4/ip_input.c
+++ b/net/ipv4/ip_input.c
@@ -339,8 +339,8 @@ static int ip_rcv_finish(struct sk_buff *skb)
          *      how the packet travels inside Linux networking.
          */
         if (!skb_dst(skb)) {
-                int err = ip_route_input(skb, iph->daddr, iph->saddr,
-                                         iph->tos, skb->dev);
+                int err = ip_route_input_noref(skb, iph->daddr, iph->saddr,
+                                               iph->tos, skb->dev);
                 if (unlikely(err)) {
                         if (err == -EXDEV)
                                 NET_INC_STATS_BH(dev_net(skb->dev),