From a43912ab1925788765208da5cd664b6f8e011d08 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Wed, 23 Sep 2009 10:28:33 +0000 Subject: 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 Signed-off-by: David S. Miller --- net/ipv4/ip_gre.c | 13 +------------ 1 file changed, 1 insertion(+), 12 deletions(-) (limited to 'net/ipv4/ip_gre.c') diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c index d9645c94a06..41ada9904d3 100644 --- a/net/ipv4/ip_gre.c +++ b/net/ipv4/ip_gre.c @@ -66,10 +66,7 @@ solution, but it supposes maintaing new variable in ALL skb, even if no tunneling is used. - Current solution: t->recursion lock breaks dead loops. It looks - like dev->tbusy flag, but I preferred new variable, because - the semantics is different. One day, when hard_start_xmit - will be multithreaded we will have to use skb->encapsulation. + Current solution: HARD_TX_LOCK lock breaks dead loops. @@ -678,11 +675,6 @@ static netdev_tx_t ipgre_tunnel_xmit(struct sk_buff *skb, struct net_device *dev __be32 dst; int mtu; - if (tunnel->recursion++) { - stats->collisions++; - goto tx_error; - } - if (dev->type == ARPHRD_ETHER) IPCB(skb)->flags = 0; @@ -820,7 +812,6 @@ static netdev_tx_t ipgre_tunnel_xmit(struct sk_buff *skb, struct net_device *dev ip_rt_put(rt); stats->tx_dropped++; dev_kfree_skb(skb); - tunnel->recursion--; return NETDEV_TX_OK; } if (skb->sk) @@ -888,7 +879,6 @@ static netdev_tx_t ipgre_tunnel_xmit(struct sk_buff *skb, struct net_device *dev nf_reset(skb); IPTUNNEL_XMIT(); - tunnel->recursion--; return NETDEV_TX_OK; tx_error_icmp: @@ -897,7 +887,6 @@ tx_error_icmp: tx_error: stats->tx_errors++; dev_kfree_skb(skb); - tunnel->recursion--; return NETDEV_TX_OK; } -- cgit v1.2.3