diff --git a/arch/x86/include/asm/nmi.h b/arch/x86/include/asm/nmi.h index 93da9c3f334..5b41b0feb6d 100644 --- a/arch/x86/include/asm/nmi.h +++ b/arch/x86/include/asm/nmi.h @@ -17,7 +17,9 @@ int do_nmi_callback(struct pt_regs *regs, int cpu); extern void die_nmi(char *str, struct pt_regs *regs, int do_panic); extern int check_nmi_watchdog(void); +#if !defined(CONFIG_NMI_WATCHDOG) extern int nmi_watchdog_enabled; +#endif extern int avail_to_resrv_perfctr_nmi_bit(unsigned int); extern int reserve_perfctr_nmi(unsigned int); extern void release_perfctr_nmi(unsigned int); diff --git a/arch/x86/kernel/apic/hw_nmi.c b/arch/x86/kernel/apic/hw_nmi.c index 8c0e6a410d0..312d772c5c3 100644 --- a/arch/x86/kernel/apic/hw_nmi.c +++ b/arch/x86/kernel/apic/hw_nmi.c @@ -32,8 +32,13 @@ static DEFINE_PER_CPU(unsigned, last_irq_sum); */ static inline unsigned int get_timer_irqs(int cpu) { - return per_cpu(irq_stat, cpu).apic_timer_irqs + - per_cpu(irq_stat, cpu).irq0_irqs; + unsigned int irqs = per_cpu(irq_stat, cpu).irq0_irqs; + +#if defined(CONFIG_X86_LOCAL_APIC) + irqs += per_cpu(irq_stat, cpu).apic_timer_irqs; +#endif + + return irqs; } static inline int mce_in_progress(void) @@ -82,6 +87,11 @@ int hw_nmi_is_cpu_stuck(struct pt_regs *regs) } } +u64 hw_nmi_get_sample_period(void) +{ + return cpu_khz * 1000; +} + void arch_trigger_all_cpu_backtrace(void) { int i; @@ -100,15 +110,16 @@ void arch_trigger_all_cpu_backtrace(void) } /* STUB calls to mimic old nmi_watchdog behaviour */ +#if defined(CONFIG_X86_LOCAL_APIC) unsigned int nmi_watchdog = NMI_NONE; EXPORT_SYMBOL(nmi_watchdog); -atomic_t nmi_active = ATOMIC_INIT(0); /* oprofile uses this */ -EXPORT_SYMBOL(nmi_active); -int nmi_watchdog_enabled; -int unknown_nmi_panic; -void cpu_nmi_set_wd_enabled(void) { return; } void acpi_nmi_enable(void) { return; } void acpi_nmi_disable(void) { return; } +#endif +atomic_t nmi_active = ATOMIC_INIT(0); /* oprofile uses this */ +EXPORT_SYMBOL(nmi_active); +int unknown_nmi_panic; +void cpu_nmi_set_wd_enabled(void) { return; } void stop_apic_nmi_watchdog(void *unused) { return; } void setup_apic_nmi_watchdog(void *unused) { return; } int __init check_nmi_watchdog(void) { return 0; } diff --git a/include/linux/nmi.h b/include/linux/nmi.h index a42ff0bef70..794e7354c5b 100644 --- a/include/linux/nmi.h +++ b/include/linux/nmi.h @@ -20,10 +20,14 @@ extern void touch_nmi_watchdog(void); extern void acpi_nmi_disable(void); extern void acpi_nmi_enable(void); #else +#ifndef CONFIG_NMI_WATCHDOG static inline void touch_nmi_watchdog(void) { touch_softlockup_watchdog(); } +#else +extern void touch_nmi_watchdog(void); +#endif static inline void acpi_nmi_disable(void) { } static inline void acpi_nmi_enable(void) { } #endif @@ -49,6 +53,11 @@ static inline bool trigger_all_cpu_backtrace(void) #ifdef CONFIG_NMI_WATCHDOG int hw_nmi_is_cpu_stuck(struct pt_regs *); +u64 hw_nmi_get_sample_period(void); +extern int nmi_watchdog_enabled; +struct ctl_table; +extern int proc_nmi_enabled(struct ctl_table *, int , + void __user *, size_t *, loff_t *); #endif #endif diff --git a/kernel/nmi_watchdog.c b/kernel/nmi_watchdog.c index 36817b214d6..73c1954a97b 100644 --- a/kernel/nmi_watchdog.c +++ b/kernel/nmi_watchdog.c @@ -30,6 +30,8 @@ static DEFINE_PER_CPU(struct perf_event *, nmi_watchdog_ev); static DEFINE_PER_CPU(int, nmi_watchdog_touch); static DEFINE_PER_CPU(long, alert_counter); +static int panic_on_timeout; + void touch_nmi_watchdog(void) { __raw_get_cpu_var(nmi_watchdog_touch) = 1; @@ -46,19 +48,49 @@ void touch_all_nmi_watchdog(void) touch_softlockup_watchdog(); } +static int __init setup_nmi_watchdog(char *str) +{ + if (!strncmp(str, "panic", 5)) { + panic_on_timeout = 1; + str = strchr(str, ','); + if (!str) + return 1; + ++str; + } + return 1; +} +__setup("nmi_watchdog=", setup_nmi_watchdog); + #ifdef CONFIG_SYSCTL /* * proc handler for /proc/sys/kernel/nmi_watchdog */ +int nmi_watchdog_enabled; + int proc_nmi_enabled(struct ctl_table *table, int write, void __user *buffer, size_t *length, loff_t *ppos) { int cpu; - if (per_cpu(nmi_watchdog_ev, smp_processor_id()) == NULL) + if (!write) { + struct perf_event *event; + for_each_online_cpu(cpu) { + event = per_cpu(nmi_watchdog_ev, cpu); + if (event->state > PERF_EVENT_STATE_OFF) { + nmi_watchdog_enabled = 1; + break; + } + } + proc_dointvec(table, write, buffer, length, ppos); + return 0; + } + + if (per_cpu(nmi_watchdog_ev, smp_processor_id()) == NULL) { nmi_watchdog_enabled = 0; - else - nmi_watchdog_enabled = 1; + proc_dointvec(table, write, buffer, length, ppos); + printk("NMI watchdog failed configuration, can not be enabled\n"); + return 0; + } touch_all_nmi_watchdog(); proc_dointvec(table, write, buffer, length, ppos); @@ -81,8 +113,6 @@ struct perf_event_attr wd_attr = { .disabled = 1, }; -static int panic_on_timeout; - void wd_overflow(struct perf_event *event, int nmi, struct perf_sample_data *data, struct pt_regs *regs) @@ -103,11 +133,11 @@ void wd_overflow(struct perf_event *event, int nmi, */ per_cpu(alert_counter,cpu) += 1; if (per_cpu(alert_counter,cpu) == 5) { - /* - * die_nmi will return ONLY if NOTIFY_STOP happens.. - */ - die_nmi("BUG: NMI Watchdog detected LOCKUP", - regs, panic_on_timeout); + if (panic_on_timeout) { + panic("NMI Watchdog detected LOCKUP on cpu %d", cpu); + } else { + WARN(1, "NMI Watchdog detected LOCKUP on cpu %d", cpu); + } } } else { per_cpu(alert_counter,cpu) = 0; @@ -133,7 +163,7 @@ cpu_callback(struct notifier_block *nfb, unsigned long action, void *hcpu) case CPU_ONLINE: case CPU_ONLINE_FROZEN: /* originally wanted the below chunk to be in CPU_UP_PREPARE, but caps is unpriv for non-CPU0 */ - wd_attr.sample_period = cpu_khz * 1000; + wd_attr.sample_period = hw_nmi_get_sample_period(); event = perf_event_create_kernel_counter(&wd_attr, hotcpu, -1, wd_overflow); if (IS_ERR(event)) { printk(KERN_ERR "nmi watchdog failed to create perf event on %i: %p\n", hotcpu, event); diff --git a/kernel/sysctl.c b/kernel/sysctl.c index 8a68b244846..ac72c9e6bd9 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -60,6 +60,10 @@ #include #endif +#ifdef CONFIG_NMI_WATCHDOG +#include +#endif + #if defined(CONFIG_SYSCTL) @@ -692,7 +696,16 @@ static struct ctl_table kern_table[] = { .mode = 0444, .proc_handler = proc_dointvec, }, -#if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86) +#if defined(CONFIG_NMI_WATCHDOG) + { + .procname = "nmi_watchdog", + .data = &nmi_watchdog_enabled, + .maxlen = sizeof (int), + .mode = 0644, + .proc_handler = proc_nmi_enabled, + }, +#endif +#if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86) && !defined(CONFIG_NMI_WATCHDOG) { .procname = "unknown_nmi_panic", .data = &unknown_nmi_panic,