openkylin
/
linux
mirror of https://gitee.com/openkylin/linux.git
9
0
Fork 0
Code Issues Projects Releases Wiki Activity

[NET]: NET_CLS_ROUTE : convert ip_rt_acct to per_cpu variables 

ip_rt_acct needs 4096 bytes per cpu to perform some accounting.
It is actually allocated as a single huge array [4096*NR_CPUS]
(rounded up to a power of two)

Converting it to a per cpu variable is wanted to :
 - Save space on machines were num_possible_cpus() < NR_CPUS
 - Better NUMA placement (each cpu gets memory on its node)

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet 2007-11-16 03:32:10 -08:00 committed by David S. Miller
parent 68f8353b48
commit 8dbde28d97
2 changed files with 4 additions and 13 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
net/ipv4/ip_input.c
View File

@ -347,7 +347,7 @@ static int ip_rcv_finish(struct sk_buff *skb)
#ifdef CONFIG_NET_CLS_ROUTE
if (unlikely(skb->dst->tclassid)) {
struct ip_rt_acct *st = ip_rt_acct + 256*smp_processor_id();
struct ip_rt_acct *st = per_cpu_ptr(ip_rt_acct, smp_processor_id());
u32 idx = skb->dst->tclassid;
st[idx&0xFF].o_packets++;
st[idx&0xFF].o_bytes+=skb->len;

15
net/ipv4/route.c
View File

@ -2858,12 +2858,10 @@ ctl_table ipv4_route_table[] = {
#endif
#ifdef CONFIG_NET_CLS_ROUTE
struct ip_rt_acct *ip_rt_acct;
/* This code sucks. But you should have seen it before! --RR */
struct ip_rt_acct *ip_rt_acct __read_mostly;
/* IP route accounting ptr for this logical cpu number. */
#define IP_RT_ACCT_CPU(i) (ip_rt_acct + i * 256)
#define IP_RT_ACCT_CPU(cpu) (per_cpu_ptr(ip_rt_acct, cpu))
#ifdef CONFIG_PROC_FS
static int ip_rt_acct_read(char *buffer, char **start, off_t offset,
@ -2923,16 +2921,9 @@ int __init ip_rt_init(void)
(jiffies ^ (jiffies >> 7)));
#ifdef CONFIG_NET_CLS_ROUTE
{
int order;
for (order = 0;
(PAGE_SIZE << order) < 256 * sizeof(struct ip_rt_acct) * NR_CPUS; order++)
/* NOTHING */;
ip_rt_acct = (struct ip_rt_acct *)__get_free_pages(GFP_KERNEL, order);
ip_rt_acct = __alloc_percpu(256 * sizeof(struct ip_rt_acct));
if (!ip_rt_acct)
panic("IP: failed to allocate ip_rt_acct\n");
memset(ip_rt_acct, 0, PAGE_SIZE << order);
}
#endif
ipv4_dst_ops.kmem_cachep =