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 <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet 2009-10-05 00:11:22 -07:00 committed by David S. Miller
parent 16c6cf8bb4
commit 0bfbedb14a
4 changed files with 12 additions and 9 deletions

View File

@ -42,9 +42,9 @@ struct ip_tunnel_prl_entry
ip_select_ident(iph, &rt->u.dst, NULL); \ ip_select_ident(iph, &rt->u.dst, NULL); \
\ \
err = ip_local_out(skb); \ err = ip_local_out(skb); \
if (net_xmit_eval(err) == 0) { \ if (likely(net_xmit_eval(err) == 0)) { \
stats->tx_bytes += pkt_len; \ txq->tx_bytes += pkt_len; \
stats->tx_packets++; \ txq->tx_packets++; \
} else { \ } else { \
stats->tx_errors++; \ stats->tx_errors++; \
stats->tx_aborted_errors++; \ stats->tx_aborted_errors++; \

View File

@ -662,7 +662,8 @@ drop_nolock:
static netdev_tx_t ipgre_tunnel_xmit(struct sk_buff *skb, struct net_device *dev) static netdev_tx_t ipgre_tunnel_xmit(struct sk_buff *skb, struct net_device *dev)
{ {
struct ip_tunnel *tunnel = netdev_priv(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 *old_iph = ip_hdr(skb);
struct iphdr *tiph; struct iphdr *tiph;
u8 tos; 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); struct sk_buff *new_skb = skb_realloc_headroom(skb, max_headroom);
if (!new_skb) { if (!new_skb) {
ip_rt_put(rt); ip_rt_put(rt);
stats->tx_dropped++; txq->tx_dropped++;
dev_kfree_skb(skb); dev_kfree_skb(skb);
return NETDEV_TX_OK; return NETDEV_TX_OK;
} }

View File

@ -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) static netdev_tx_t ipip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev)
{ {
struct ip_tunnel *tunnel = netdev_priv(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 iphdr *tiph = &tunnel->parms.iph;
u8 tos = tunnel->parms.iph.tos; u8 tos = tunnel->parms.iph.tos;
__be16 df = tiph->frag_off; __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); struct sk_buff *new_skb = skb_realloc_headroom(skb, max_headroom);
if (!new_skb) { if (!new_skb) {
ip_rt_put(rt); ip_rt_put(rt);
stats->tx_dropped++; txq->tx_dropped++;
dev_kfree_skb(skb); dev_kfree_skb(skb);
return NETDEV_TX_OK; return NETDEV_TX_OK;
} }

View File

@ -555,7 +555,8 @@ static netdev_tx_t ipip6_tunnel_xmit(struct sk_buff *skb,
struct net_device *dev) struct net_device *dev)
{ {
struct ip_tunnel *tunnel = netdev_priv(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 iphdr *tiph = &tunnel->parms.iph;
struct ipv6hdr *iph6 = ipv6_hdr(skb); struct ipv6hdr *iph6 = ipv6_hdr(skb);
u8 tos = tunnel->parms.iph.tos; 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); struct sk_buff *new_skb = skb_realloc_headroom(skb, max_headroom);
if (!new_skb) { if (!new_skb) {
ip_rt_put(rt); ip_rt_put(rt);
stats->tx_dropped++; txq->tx_dropped++;
dev_kfree_skb(skb); dev_kfree_skb(skb);
return NETDEV_TX_OK; return NETDEV_TX_OK;
} }