tunnel: eliminate recursion field

It seems recursion field from "struct ip_tunnel" is not anymore needed.
recursion prevention is done at the upper level (in dev_queue_xmit()),
since we use HARD_TX_LOCK protection for tunnels.

This avoids a cache line ping pong on "struct ip_tunnel" : This structure
should be now mostly read on xmit and receive paths.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 0 insertions, 7 deletions

diff --git a/net/ipv6/ip6_tunnel.c b/net/ipv6/ip6_tunnel.c
index 7d25bbe32110..c595bbe1ed99 100644
--- a/net/ipv6/ip6_tunnel.c
+++ b/net/ipv6/ip6_tunnel.c
@@ -1043,11 +1043,6 @@ ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev)
         struct net_device_stats *stats = &t->dev->stats;
         int ret;
 
-        if (t->recursion++) {
-                stats->collisions++;
-                goto tx_err;
-        }
-
         switch (skb->protocol) {
         case htons(ETH_P_IP):
                 ret = ip4ip6_tnl_xmit(skb, dev);
@@ -1062,14 +1057,12 @@ ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev)
         if (ret < 0)
                 goto tx_err;
 
-        t->recursion--;
         return NETDEV_TX_OK;
 
 tx_err:
         stats->tx_errors++;
         stats->tx_dropped++;
         kfree_skb(skb);
-        t->recursion--;
         return NETDEV_TX_OK;
 }