[PATCH] more for_each_cpu() conversions
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>
diff --git a/arch/i386/kernel/cpu/cpufreq/powernow-k8.c b/arch/i386/kernel/cpu/cpufreq/powernow-k8.c
index e11a092..3d5110b 100644
--- a/arch/i386/kernel/cpu/cpufreq/powernow-k8.c
+++ b/arch/i386/kernel/cpu/cpufreq/powernow-k8.c
@@ -1145,9 +1145,7 @@
{
unsigned int i, supported_cpus = 0;
- for (i=0; i<NR_CPUS; i++) {
- if (!cpu_online(i))
- continue;
+ for_each_cpu(i) {
if (check_supported_cpu(i))
supported_cpus++;
}
diff --git a/arch/i386/kernel/io_apic.c b/arch/i386/kernel/io_apic.c
index fd1c60c..311b4e7 100644
--- a/arch/i386/kernel/io_apic.c
+++ b/arch/i386/kernel/io_apic.c
@@ -351,8 +351,8 @@
{
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 @@
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 @@
}
}
/* 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 @@
*/
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 @@
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 @@
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;
}
diff --git a/arch/i386/kernel/nmi.c b/arch/i386/kernel/nmi.c
index 1db34ef..9074818 100644
--- a/arch/i386/kernel/nmi.c
+++ b/arch/i386/kernel/nmi.c
@@ -143,7 +143,7 @@
local_irq_enable();
mdelay((10*1000)/nmi_hz); // wait 10 ticks
- for (cpu = 0; cpu < NR_CPUS; cpu++) {
+ for_each_cpu(cpu) {
#ifdef CONFIG_SMP
/* Check cpu_callin_map here because that is set
after the timer is started. */
@@ -510,7 +510,7 @@
* Just reset the alert counters, (other CPUs might be
* spinning on locks we hold):
*/
- for (i = 0; i < NR_CPUS; i++)
+ for_each_cpu(i)
alert_counter[i] = 0;
/*