hollalinux
/
linux-sg2042
mirror of https://github.com/sophgo/linux-riscv.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

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>
This commit is contained in:
Eric Dumazet 2009-09-23 10:28:33 +00:00 committed by David S. Miller
parent edf42a27e8
commit a43912ab19
5 changed files with 1 additions and 36 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
include/net/ipip.h
View File

@ -12,7 +12,6 @@ struct ip_tunnel
struct ip_tunnel *next;
struct net_device *dev;
int recursion; /* Depth of hard_start_xmit recursion */
int err_count; /* Number of arrived ICMP errors */
unsigned long err_time; /* Time when the last ICMP error arrived */

13
net/ipv4/ip_gre.c
View File

@ -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;
}

8
net/ipv4/ipip.c
View File

@ -402,11 +402,6 @@ static netdev_tx_t ipip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev)
__be32 dst = tiph->daddr;
int mtu;
if (tunnel->recursion++) {
stats->collisions++;
goto tx_error;
}
if (skb->protocol != htons(ETH_P_IP))
goto tx_error;
@ -485,7 +480,6 @@ static netdev_tx_t ipip_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)
@ -523,7 +517,6 @@ static netdev_tx_t ipip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev)
nf_reset(skb);
IPTUNNEL_XMIT();
tunnel->recursion--;
return NETDEV_TX_OK;
tx_error_icmp:
@ -531,7 +524,6 @@ tx_error_icmp:
tx_error:
stats->tx_errors++;
dev_kfree_skb(skb);
tunnel->recursion--;
return NETDEV_TX_OK;
}

7
net/ipv6/ip6_tunnel.c
View File

@ -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;
}

8
net/ipv6/sit.c
View File

@ -626,11 +626,6 @@ static netdev_tx_t ipip6_tunnel_xmit(struct sk_buff *skb,
struct in6_addr *addr6;
int addr_type;
if (tunnel->recursion++) {
stats->collisions++;
goto tx_error;
}
if (skb->protocol != htons(ETH_P_IPV6))
goto tx_error;
@ -753,7 +748,6 @@ static netdev_tx_t ipip6_tunnel_xmit(struct sk_buff *skb,
ip_rt_put(rt);
stats->tx_dropped++;
dev_kfree_skb(skb);
tunnel->recursion--;
return NETDEV_TX_OK;
}
if (skb->sk)
@ -794,7 +788,6 @@ static netdev_tx_t ipip6_tunnel_xmit(struct sk_buff *skb,
nf_reset(skb);
IPTUNNEL_XMIT();
tunnel->recursion--;
return NETDEV_TX_OK;
tx_error_icmp:
@ -802,7 +795,6 @@ tx_error_icmp:
tx_error:
stats->tx_errors++;
dev_kfree_skb(skb);
tunnel->recursion--;
return NETDEV_TX_OK;
}