Commit 394e3902 authored by Andrew Morton's avatar Andrew Morton Committed by Linus Torvalds
Browse files

[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: default avatarKyle 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: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent 63872f87

arch/cris/kernel/irq.c

+4 −6
Original line number Diff line number Diff line
@@ -52,8 +52,7 @@ int show_interrupts(struct seq_file *p, void *v) 


	if (i == 0) {

		seq_printf(p, "           ");

		for (j=0; j<NR_CPUS; j++)

			if (cpu_online(j))

		for_each_online_cpu(j)

			seq_printf(p, "CPU%d       ",j);

		seq_putc(p, '\n');

	}
@@ -67,8 +66,7 @@ int show_interrupts(struct seq_file *p, void *v) 
#ifndef CONFIG_SMP

		seq_printf(p, "%10u ", kstat_irqs(i));

#else

		for (j = 0; j < NR_CPUS; j++)

			if (cpu_online(j))

		for_each_online_cpu(j)

			seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);

#endif

		seq_printf(p, " %14s", irq_desc[i].handler->typename);

arch/frv/kernel/irq.c

+4 −6
Original line number Diff line number Diff line
@@ -75,8 +75,7 @@ int show_interrupts(struct seq_file *p, void *v) 
	switch (i) {

	case 0:

		seq_printf(p, "           ");

		for (j = 0; j < NR_CPUS; j++)

			if (cpu_online(j))

		for_each_online_cpu(j)

			seq_printf(p, "CPU%d       ",j);



		seq_putc(p, '\n');
@@ -100,8 +99,7 @@ int show_interrupts(struct seq_file *p, void *v) 
#ifndef CONFIG_SMP

		seq_printf(p, "%10u ", kstat_irqs(i));

#else

		for (j = 0; j < NR_CPUS; j++)

			if (cpu_online(j))

		for_each_online_cpu(j)

			seq_printf(p, "%10u ", kstat_cpu(j).irqs[i - 1]);

#endif

arch/i386/kernel/cpu/cpufreq/powernow-k8.c

+1 −3
Original line number Diff line number Diff line
@@ -1145,9 +1145,7 @@ static int __cpuinit powernowk8_init(void) 
{

	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++;

	}

arch/i386/kernel/io_apic.c

+9 −13
Original line number Diff line number Diff line
@@ -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;

}

arch/i386/kernel/nmi.c

+2 −2
Original line number Diff line number Diff line
@@ -143,7 +143,7 @@ static int __init check_nmi_watchdog(void) 
	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 @@ void touch_nmi_watchdog (void) 
	 * 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;



	/*

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