| /* |
| * HW NMI watchdog support |
| * |
| * started by Don Zickus, Copyright (C) 2010 Red Hat, Inc. |
| * |
| * Arch specific calls to support NMI watchdog |
| * |
| * Bits copied from original nmi.c file |
| * |
| */ |
| #include <asm/apic.h> |
| |
| #include <linux/cpumask.h> |
| #include <linux/kdebug.h> |
| #include <linux/notifier.h> |
| #include <linux/kprobes.h> |
| #include <linux/nmi.h> |
| #include <linux/module.h> |
| |
| #ifdef CONFIG_HARDLOCKUP_DETECTOR |
| u64 hw_nmi_get_sample_period(void) |
| { |
| return (u64)(cpu_khz) * 1000 * 60; |
| } |
| #endif |
| |
| #ifndef CONFIG_HARDLOCKUP_DETECTOR |
| void touch_nmi_watchdog(void) |
| { |
| touch_softlockup_watchdog(); |
| } |
| EXPORT_SYMBOL(touch_nmi_watchdog); |
| #endif |
| #ifdef arch_trigger_all_cpu_backtrace |
| /* For reliability, we're prepared to waste bits here. */ |
| static DECLARE_BITMAP(backtrace_mask, NR_CPUS) __read_mostly; |
| |
| void arch_trigger_all_cpu_backtrace(void) |
| { |
| int i; |
| |
| cpumask_copy(to_cpumask(backtrace_mask), cpu_online_mask); |
| |
| printk(KERN_INFO "sending NMI to all CPUs:\n"); |
| apic->send_IPI_all(NMI_VECTOR); |
| |
| /* Wait for up to 10 seconds for all CPUs to do the backtrace */ |
| for (i = 0; i < 10 * 1000; i++) { |
| if (cpumask_empty(to_cpumask(backtrace_mask))) |
| break; |
| 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 |