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

[PATCH] more for_each_cpu() conversions

Browse Source 
When we stop allocating percpu memory for not-possible CPUs we must not touch
the percpu data for not-possible CPUs at all.  The correct way of doing this
is to test cpu_possible() or to use for_each_cpu().

This patch is a kernel-wide sweep of all instances of NR_CPUS.  I found very
few instances of this bug, if any.  But the patch converts lots of open-coded
test to use the preferred helper macros.

Cc: Mikael Starvik <starvik@axis.com>
Cc: David Howells <dhowells@redhat.com>
Acked-by: Kyle McMartin <kyle@parisc-linux.org>
Cc: Anton Blanchard <anton@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: William Lee Irwin III <wli@holomorphy.com>
Cc: Andi Kleen <ak@muc.de>
Cc: Christian Zankel <chris@zankel.net>
Cc: Philippe Elie <phil.el@wanadoo.fr>
Cc: Nathan Scott <nathans@sgi.com>
Cc: Jens Axboe <axboe@suse.de>
Cc: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Andrew Morton
2006-03-23 03:01:05 -08:00
committed by Linus Torvalds
parent 63872f87a1
commit 394e3902c5
42 changed files with 137 additions and 222 deletions
Download Patch File Download Diff File Expand all files Collapse all files

22
arch/i386/kernel/io_apic.c
View File

@ -351,8 +351,8 @@ static inline void rotate_irqs_among_cpus(unsigned long useful_load_threshold)
{
int i, j;
Dprintk("Rotating IRQs among CPUs.\n");
for (i = 0; i < NR_CPUS; i++) {
for (j = 0; cpu_online(i) && (j < NR_IRQS); j++) {
for_each_online_cpu(i) {
for (j = 0; j < NR_IRQS; j++) {
if (!irq_desc[j].action)
continue;
/* Is it a significant load ? */
@ -381,7 +381,7 @@ static void do_irq_balance(void)
unsigned long imbalance = 0;
cpumask_t allowed_mask, target_cpu_mask, tmp;
for (i = 0; i < NR_CPUS; i++) {
for_each_cpu(i) {
int package_index;
CPU_IRQ(i) = 0;
if (!cpu_online(i))
@ -422,9 +422,7 @@ static void do_irq_balance(void)
}
}
/* Find the least loaded processor package */
for (i = 0; i < NR_CPUS; i++) {
if (!cpu_online(i))
continue;
for_each_online_cpu(i) {
if (i != CPU_TO_PACKAGEINDEX(i))
continue;
if (min_cpu_irq > CPU_IRQ(i)) {
@ -441,9 +439,7 @@ tryanothercpu:
*/
tmp_cpu_irq = 0;
tmp_loaded = -1;
for (i = 0; i < NR_CPUS; i++) {
if (!cpu_online(i))
continue;
for_each_online_cpu(i) {
if (i != CPU_TO_PACKAGEINDEX(i))
continue;
if (max_cpu_irq <= CPU_IRQ(i))
@ -619,9 +615,7 @@ static int __init balanced_irq_init(void)
if (smp_num_siblings > 1 && !cpus_empty(tmp))
physical_balance = 1;
for (i = 0; i < NR_CPUS; i++) {
if (!cpu_online(i))
continue;
for_each_online_cpu(i) {
irq_cpu_data[i].irq_delta = kmalloc(sizeof(unsigned long) * NR_IRQS, GFP_KERNEL);
irq_cpu_data[i].last_irq = kmalloc(sizeof(unsigned long) * NR_IRQS, GFP_KERNEL);
if (irq_cpu_data[i].irq_delta == NULL || irq_cpu_data[i].last_irq == NULL) {
@ -638,9 +632,11 @@ static int __init balanced_irq_init(void)
else
printk(KERN_ERR "balanced_irq_init: failed to spawn balanced_irq");
failed:
for (i = 0; i < NR_CPUS; i++) {
for_each_cpu(i) {
kfree(irq_cpu_data[i].irq_delta);
irq_cpu_data[i].irq_delta = NULL;
kfree(irq_cpu_data[i].last_irq);
irq_cpu_data[i].last_irq = NULL;
}
return 0;
}