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x86, mrst: Fix APB timer per cpu clockevent 

The current APB timer code incorrectly registers a static copy of the
clockevent device for the boot CPU. The per cpu clockevent should be
used instead.

This bug was hidden by zero-initialized data; as such it did not get
exposed in testing, but was discovered by code review.

Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
LKML-Reference: <1267592494-7723-1-git-send-email-jacob.jun.pan@linux.intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
This commit is contained in:
Jacob Pan 2010-03-02 21:01:34 -08:00 committed by H. Peter Anvin
parent d8111cd91a
commit 3010673ef5
1 changed files with 8 additions and 4 deletions
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12
arch/x86/kernel/apb_timer.c
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@ -84,9 +84,10 @@ struct apbt_dev {
int disable_apbt_percpu __cpuinitdata;
static DEFINE_PER_CPU(struct apbt_dev, cpu_apbt_dev);
#ifdef CONFIG_SMP
static unsigned int apbt_num_timers_used;
static DEFINE_PER_CPU(struct apbt_dev, cpu_apbt_dev);
static struct apbt_dev *apbt_devs;
#endif
@ -302,6 +303,7 @@ static void apbt_disable_int(int n)
static int __init apbt_clockevent_register(void)
{
struct sfi_timer_table_entry *mtmr;
struct apbt_dev *adev = &__get_cpu_var(cpu_apbt_dev);
mtmr = sfi_get_mtmr(APBT_CLOCKEVENT0_NUM);
if (mtmr == NULL) {
@ -329,22 +331,24 @@ static int __init apbt_clockevent_register(void)
* global if not used for per cpu timer.
*/
apbt_clockevent.cpumask = cpumask_of(smp_processor_id());
adev->num = smp_processor_id();
memcpy(&adev->evt, &apbt_clockevent, sizeof(struct clock_event_device));
if (disable_apbt_percpu) {
apbt_clockevent.rating = APBT_CLOCKEVENT_RATING - 100;
global_clock_event = &apbt_clockevent;
global_clock_event = &adev->evt;
printk(KERN_DEBUG "%s clockevent registered as global\n",
global_clock_event->name);
}
if (request_irq(apbt_clockevent.irq, apbt_interrupt_handler,
IRQF_TIMER | IRQF_DISABLED | IRQF_NOBALANCING,
apbt_clockevent.name, &apbt_clockevent)) {
apbt_clockevent.name, adev)) {
printk(KERN_ERR "Failed request IRQ for APBT%d\n",
apbt_clockevent.irq);
}
clockevents_register_device(&apbt_clockevent);
clockevents_register_device(&adev->evt);
/* Start APBT 0 interrupts */
apbt_enable_int(APBT_CLOCKEVENT0_NUM);