kybaaz/linux-xiaomi-chiron
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

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
include/linux/netfilter/x_tables.h
View file

@ -397,7 +397,7 @@ struct xt_table_info {
* @stacksize jumps (number of user chains) can possibly be made.
*/
unsigned int stacksize;
unsigned int *stackptr;
unsigned int __percpu *stackptr;
void ***jumpstack;
/* ipt_entry tables: one per CPU */
/* Note : this field MUST be the last one, see XT_TABLE_INFO_SZ */