x86: Move trigger_all_cpu_backtrace to its own die_notifier

As part of the transition of the nmi watchdog to something more
generic, the trigger_all_cpu_backtrace code is getting left behind.
Put it in its own die_notifier so it can still be used.

V2:
- use arch_spin_locks

Signed-off-by: Don Zickus <dzickus@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Eric Paris <eparis@redhat.com>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
LKML-Reference: <1273266711-18706-6-git-send-email-dzickus@redhat.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
This commit is contained in:
Don Zickus 2010-05-07 17:11:48 -04:00 committed by Frederic Weisbecker
parent f69bcf60c3
commit 7cbb7e7fa4

View File

@ -17,6 +17,10 @@
#include <linux/cpumask.h> #include <linux/cpumask.h>
#include <linux/kernel_stat.h> #include <linux/kernel_stat.h>
#include <asm/mce.h> #include <asm/mce.h>
#include <linux/kdebug.h>
#include <linux/notifier.h>
#include <linux/kprobes.h>
#include <linux/nmi.h> #include <linux/nmi.h>
#include <linux/module.h> #include <linux/module.h>
@ -54,20 +58,6 @@ int hw_nmi_is_cpu_stuck(struct pt_regs *regs)
unsigned int sum; unsigned int sum;
int cpu = smp_processor_id(); int cpu = smp_processor_id();
/* FIXME: cheap hack for this check, probably should get its own
* die_notifier handler
*/
if (cpumask_test_cpu(cpu, to_cpumask(backtrace_mask))) {
static DEFINE_SPINLOCK(lock); /* Serialise the printks */
spin_lock(&lock);
printk(KERN_WARNING "NMI backtrace for cpu %d\n", cpu);
show_regs(regs);
dump_stack();
spin_unlock(&lock);
cpumask_clear_cpu(cpu, to_cpumask(backtrace_mask));
}
/* if we are doing an mce, just assume the cpu is not stuck */ /* if we are doing an mce, just assume the cpu is not stuck */
/* Could check oops_in_progress here too, but it's safer not to */ /* Could check oops_in_progress here too, but it's safer not to */
if (mce_in_progress()) if (mce_in_progress())
@ -109,6 +99,53 @@ void arch_trigger_all_cpu_backtrace(void)
mdelay(1); mdelay(1);
} }
} }
static int __kprobes
arch_trigger_all_cpu_backtrace_handler(struct notifier_block *self,
unsigned long cmd, void *__args)
{
struct die_args *args = __args;
struct pt_regs *regs;
int cpu = smp_processor_id();
switch (cmd) {
case DIE_NMI:
case DIE_NMI_IPI:
break;
default:
return NOTIFY_DONE;
}
regs = args->regs;
if (cpumask_test_cpu(cpu, to_cpumask(backtrace_mask))) {
static arch_spinlock_t lock = __ARCH_SPIN_LOCK_UNLOCKED;
arch_spin_lock(&lock);
printk(KERN_WARNING "NMI backtrace for cpu %d\n", cpu);
show_regs(regs);
dump_stack();
arch_spin_unlock(&lock);
cpumask_clear_cpu(cpu, to_cpumask(backtrace_mask));
return NOTIFY_STOP;
}
return NOTIFY_DONE;
}
static __read_mostly struct notifier_block backtrace_notifier = {
.notifier_call = arch_trigger_all_cpu_backtrace_handler,
.next = NULL,
.priority = 1
};
static int __init register_trigger_all_cpu_backtrace(void)
{
register_die_notifier(&backtrace_notifier);
return 0;
}
early_initcall(register_trigger_all_cpu_backtrace);
#endif #endif
/* STUB calls to mimic old nmi_watchdog behaviour */ /* STUB calls to mimic old nmi_watchdog behaviour */