lk/linux-kernel-test
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

netfilter: xtables: stackptr should be percpu

Browse Source 
commit f3c5c1bfd4 (netfilter: xtables: make ip_tables reentrant)
introduced a performance regression, because stackptr array is shared by
all cpus, adding cache line ping pongs. (16 cpus share a 64 bytes cache
line)

Fix this using alloc_percpu()

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Acked-By: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
This commit is contained in:
Eric Dumazet
2010-05-31 16:41:35 +02:00
committed by Patrick McHardy
parent c936e8bd1d
commit 7489aec8ee
4 changed files with 6 additions and 13 deletions
Download Patch File Download Diff File Expand all files Collapse all files

2
net/ipv4/netfilter/ip_tables.c
View File

@ -336,7 +336,7 @@ ipt_do_table(struct sk_buff *skb,
cpu = smp_processor_id();
table_base = private->entries[cpu];
jumpstack = (struct ipt_entry **)private->jumpstack[cpu];
stackptr = &private->stackptr[cpu];
stackptr = per_cpu_ptr(private->stackptr, cpu);
origptr = *stackptr;
e = get_entry(table_base, private->hook_entry[hook]);