diff options
Diffstat (limited to 'arch/x86/kernel/reboot.c')
-rw-r--r-- | arch/x86/kernel/reboot.c | 83 |
1 files changed, 83 insertions, 0 deletions
diff --git a/arch/x86/kernel/reboot.c b/arch/x86/kernel/reboot.c index 724adfc63cb9..364edeecc235 100644 --- a/arch/x86/kernel/reboot.c +++ b/arch/x86/kernel/reboot.c | |||
@@ -21,6 +21,9 @@ | |||
21 | # include <asm/iommu.h> | 21 | # include <asm/iommu.h> |
22 | #endif | 22 | #endif |
23 | 23 | ||
24 | #include <mach_ipi.h> | ||
25 | |||
26 | |||
24 | /* | 27 | /* |
25 | * Power off function, if any | 28 | * Power off function, if any |
26 | */ | 29 | */ |
@@ -514,3 +517,83 @@ void machine_crash_shutdown(struct pt_regs *regs) | |||
514 | machine_ops.crash_shutdown(regs); | 517 | machine_ops.crash_shutdown(regs); |
515 | } | 518 | } |
516 | #endif | 519 | #endif |
520 | |||
521 | |||
522 | #if defined(CONFIG_SMP) && defined(CONFIG_X86_LOCAL_APIC) | ||
523 | |||
524 | /* This keeps a track of which one is crashing cpu. */ | ||
525 | static int crashing_cpu; | ||
526 | static nmi_shootdown_cb shootdown_callback; | ||
527 | |||
528 | static atomic_t waiting_for_crash_ipi; | ||
529 | |||
530 | static int crash_nmi_callback(struct notifier_block *self, | ||
531 | unsigned long val, void *data) | ||
532 | { | ||
533 | int cpu; | ||
534 | |||
535 | if (val != DIE_NMI_IPI) | ||
536 | return NOTIFY_OK; | ||
537 | |||
538 | cpu = raw_smp_processor_id(); | ||
539 | |||
540 | /* Don't do anything if this handler is invoked on crashing cpu. | ||
541 | * Otherwise, system will completely hang. Crashing cpu can get | ||
542 | * an NMI if system was initially booted with nmi_watchdog parameter. | ||
543 | */ | ||
544 | if (cpu == crashing_cpu) | ||
545 | return NOTIFY_STOP; | ||
546 | local_irq_disable(); | ||
547 | |||
548 | shootdown_callback(cpu, (struct die_args *)data); | ||
549 | |||
550 | atomic_dec(&waiting_for_crash_ipi); | ||
551 | /* Assume hlt works */ | ||
552 | halt(); | ||
553 | for (;;) | ||
554 | cpu_relax(); | ||
555 | |||
556 | return 1; | ||
557 | } | ||
558 | |||
559 | static void smp_send_nmi_allbutself(void) | ||
560 | { | ||
561 | cpumask_t mask = cpu_online_map; | ||
562 | cpu_clear(safe_smp_processor_id(), mask); | ||
563 | if (!cpus_empty(mask)) | ||
564 | send_IPI_mask(mask, NMI_VECTOR); | ||
565 | } | ||
566 | |||
567 | static struct notifier_block crash_nmi_nb = { | ||
568 | .notifier_call = crash_nmi_callback, | ||
569 | }; | ||
570 | |||
571 | void nmi_shootdown_cpus(nmi_shootdown_cb callback) | ||
572 | { | ||
573 | unsigned long msecs; | ||
574 | |||
575 | /* Make a note of crashing cpu. Will be used in NMI callback.*/ | ||
576 | crashing_cpu = safe_smp_processor_id(); | ||
577 | |||
578 | shootdown_callback = callback; | ||
579 | |||
580 | atomic_set(&waiting_for_crash_ipi, num_online_cpus() - 1); | ||
581 | /* Would it be better to replace the trap vector here? */ | ||
582 | if (register_die_notifier(&crash_nmi_nb)) | ||
583 | return; /* return what? */ | ||
584 | /* Ensure the new callback function is set before sending | ||
585 | * out the NMI | ||
586 | */ | ||
587 | wmb(); | ||
588 | |||
589 | smp_send_nmi_allbutself(); | ||
590 | |||
591 | msecs = 1000; /* Wait at most a second for the other cpus to stop */ | ||
592 | while ((atomic_read(&waiting_for_crash_ipi) > 0) && msecs) { | ||
593 | mdelay(1); | ||
594 | msecs--; | ||
595 | } | ||
596 | |||
597 | /* Leave the nmi callback set */ | ||
598 | } | ||
599 | #endif | ||