From 0bfbedb14a8a96c529341bec88991a92b41fac72 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Mon, 5 Oct 2009 00:11:22 -0700 Subject: [PATCH] tunnels: Optimize tx path We currently dirty a cache line to update tunnel device stats (tx_packets/tx_bytes). We better use the txq->tx_bytes/tx_packets counters that already are present in cpu cache, in the cache line shared with txq->_xmit_lock This patch extends IPTUNNEL_XMIT() macro to use txq pointer provided by the caller. Also &tunnel->dev->stats can be replaced by &dev->stats Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- include/net/ipip.h | 6 +++--- net/ipv4/ip_gre.c | 5 +++-- net/ipv4/ipip.c | 5 +++-- net/ipv6/sit.c | 5 +++-- 4 files changed, 12 insertions(+), 9 deletions(-) diff --git a/include/net/ipip.h b/include/net/ipip.h index 87acf8f3a155..0159221a8509 100644 --- a/include/net/ipip.h +++ b/include/net/ipip.h @@ -42,9 +42,9 @@ struct ip_tunnel_prl_entry ip_select_ident(iph, &rt->u.dst, NULL); \ \ err = ip_local_out(skb); \ - if (net_xmit_eval(err) == 0) { \ - stats->tx_bytes += pkt_len; \ - stats->tx_packets++; \ + if (likely(net_xmit_eval(err) == 0)) { \ + txq->tx_bytes += pkt_len; \ + txq->tx_packets++; \ } else { \ stats->tx_errors++; \ stats->tx_aborted_errors++; \ diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c index 41ada9904d31..89ff9d5b1500 100644 --- a/net/ipv4/ip_gre.c +++ b/net/ipv4/ip_gre.c @@ -662,7 +662,8 @@ drop_nolock: static netdev_tx_t ipgre_tunnel_xmit(struct sk_buff *skb, struct net_device *dev) { struct ip_tunnel *tunnel = netdev_priv(dev); - struct net_device_stats *stats = &tunnel->dev->stats; + struct net_device_stats *stats = &dev->stats; + struct netdev_queue *txq = netdev_get_tx_queue(dev, 0); struct iphdr *old_iph = ip_hdr(skb); struct iphdr *tiph; u8 tos; @@ -810,7 +811,7 @@ static netdev_tx_t ipgre_tunnel_xmit(struct sk_buff *skb, struct net_device *dev struct sk_buff *new_skb = skb_realloc_headroom(skb, max_headroom); if (!new_skb) { ip_rt_put(rt); - stats->tx_dropped++; + txq->tx_dropped++; dev_kfree_skb(skb); return NETDEV_TX_OK; } diff --git a/net/ipv4/ipip.c b/net/ipv4/ipip.c index 08ccd344de7a..6a5539236ab3 100644 --- a/net/ipv4/ipip.c +++ b/net/ipv4/ipip.c @@ -390,7 +390,8 @@ static int ipip_rcv(struct sk_buff *skb) static netdev_tx_t ipip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev) { struct ip_tunnel *tunnel = netdev_priv(dev); - struct net_device_stats *stats = &tunnel->dev->stats; + struct net_device_stats *stats = &dev->stats; + struct netdev_queue *txq = netdev_get_tx_queue(dev, 0); struct iphdr *tiph = &tunnel->parms.iph; u8 tos = tunnel->parms.iph.tos; __be16 df = tiph->frag_off; @@ -478,7 +479,7 @@ static netdev_tx_t ipip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev) struct sk_buff *new_skb = skb_realloc_headroom(skb, max_headroom); if (!new_skb) { ip_rt_put(rt); - stats->tx_dropped++; + txq->tx_dropped++; dev_kfree_skb(skb); return NETDEV_TX_OK; } diff --git a/net/ipv6/sit.c b/net/ipv6/sit.c index dbd19a78ca73..99da272951dc 100644 --- a/net/ipv6/sit.c +++ b/net/ipv6/sit.c @@ -555,7 +555,8 @@ static netdev_tx_t ipip6_tunnel_xmit(struct sk_buff *skb, struct net_device *dev) { struct ip_tunnel *tunnel = netdev_priv(dev); - struct net_device_stats *stats = &tunnel->dev->stats; + struct net_device_stats *stats = &dev->stats; + struct netdev_queue *txq = netdev_get_tx_queue(dev, 0); struct iphdr *tiph = &tunnel->parms.iph; struct ipv6hdr *iph6 = ipv6_hdr(skb); u8 tos = tunnel->parms.iph.tos; @@ -688,7 +689,7 @@ static netdev_tx_t ipip6_tunnel_xmit(struct sk_buff *skb, struct sk_buff *new_skb = skb_realloc_headroom(skb, max_headroom); if (!new_skb) { ip_rt_put(rt); - stats->tx_dropped++; + txq->tx_dropped++; dev_kfree_skb(skb); return NETDEV_TX_OK; }