X-Git-Url: http://ftp.safe.ca/?p=safe%2Fjmp%2Flinux-2.6;a=blobdiff_plain;f=arch%2Fx86%2Fkernel%2Fnmi.c;fp=arch%2Fx86%2Fkernel%2Fnmi_32.c;h=ec024b3baad0764821c036d0aa2552397f76f017;hp=11008e0857c053d67f746c0b1d91aae6436ffc7b;hb=1a781a777b2f6ac46523fe92396215762ced624d;hpb=42a2f217a5e324ed5f2373ab1b7a0a15187c4d6c diff --git a/arch/x86/kernel/nmi_32.c b/arch/x86/kernel/nmi.c similarity index 68% rename from arch/x86/kernel/nmi_32.c rename to arch/x86/kernel/nmi.c index 11008e0..ec024b3 100644 --- a/arch/x86/kernel/nmi_32.c +++ b/arch/x86/kernel/nmi.c @@ -11,10 +11,13 @@ * Mikael Pettersson : PM converted to driver model. Disable/enable API. */ +#include + +#include +#include #include #include #include -#include #include #include #include @@ -22,12 +25,18 @@ #include #include #include -#include +#include +#include +#include #include #include +#include +#include -#include "mach_traps.h" +#include + +#include int unknown_nmi_panic; int nmi_watchdog_enabled; @@ -41,28 +50,65 @@ static cpumask_t backtrace_mask = CPU_MASK_NONE; * 0: the lapic NMI watchdog is disabled, but can be enabled */ atomic_t nmi_active = ATOMIC_INIT(0); /* oprofile uses this */ +EXPORT_SYMBOL(nmi_active); -unsigned int nmi_watchdog = NMI_DEFAULT; -static unsigned int nmi_hz = HZ; +unsigned int nmi_watchdog = NMI_NONE; +EXPORT_SYMBOL(nmi_watchdog); +static int panic_on_timeout; + +static unsigned int nmi_hz = HZ; static DEFINE_PER_CPU(short, wd_enabled); +static int endflag __initdata; -static int endflag __initdata = 0; +static inline unsigned int get_nmi_count(int cpu) +{ +#ifdef CONFIG_X86_64 + return cpu_pda(cpu)->__nmi_count; +#else + return nmi_count(cpu); +#endif +} + +static inline int mce_in_progress(void) +{ +#if defined(CONFIG_X86_64) && defined(CONFIG_X86_MCE) + return atomic_read(&mce_entry) > 0; +#endif + return 0; +} + +/* + * Take the local apic timer and PIT/HPET into account. We don't + * know which one is active, when we have highres/dyntick on + */ +static inline unsigned int get_timer_irqs(int cpu) +{ +#ifdef CONFIG_X86_64 + return read_pda(apic_timer_irqs) + read_pda(irq0_irqs); +#else + return per_cpu(irq_stat, cpu).apic_timer_irqs + + per_cpu(irq_stat, cpu).irq0_irqs; +#endif +} #ifdef CONFIG_SMP -/* The performance counters used by NMI_LOCAL_APIC don't trigger when +/* + * The performance counters used by NMI_LOCAL_APIC don't trigger when * the CPU is idle. To make sure the NMI watchdog really ticks on all * CPUs during the test make them busy. */ static __init void nmi_cpu_busy(void *data) { local_irq_enable_in_hardirq(); - /* Intentionally don't use cpu_relax here. This is - to make sure that the performance counter really ticks, - even if there is a simulator or similar that catches the - pause instruction. On a real HT machine this is fine because - all other CPUs are busy with "useless" delay loops and don't - care if they get somewhat less cycles. */ + /* + * Intentionally don't use cpu_relax here. This is + * to make sure that the performance counter really ticks, + * even if there is a simulator or similar that catches the + * pause instruction. On a real HT machine this is fine because + * all other CPUs are busy with "useless" delay loops and don't + * care if they get somewhat less cycles. + */ while (endflag == 0) mb(); } @@ -73,15 +119,12 @@ int __init check_nmi_watchdog(void) unsigned int *prev_nmi_count; int cpu; - if ((nmi_watchdog == NMI_NONE) || (nmi_watchdog == NMI_DISABLED)) - return 0; - - if (!atomic_read(&nmi_active)) + if (!nmi_watchdog_active() || !atomic_read(&nmi_active)) return 0; - prev_nmi_count = kmalloc(NR_CPUS * sizeof(int), GFP_KERNEL); + prev_nmi_count = kmalloc(nr_cpu_ids * sizeof(int), GFP_KERNEL); if (!prev_nmi_count) - return -1; + goto error; printk(KERN_INFO "Testing NMI watchdog ... "); @@ -91,25 +134,19 @@ int __init check_nmi_watchdog(void) #endif for_each_possible_cpu(cpu) - prev_nmi_count[cpu] = nmi_count(cpu); + prev_nmi_count[cpu] = get_nmi_count(cpu); local_irq_enable(); - mdelay((20*1000)/nmi_hz); // wait 20 ticks + mdelay((20 * 1000) / nmi_hz); /* wait 20 ticks */ - for_each_possible_cpu(cpu) { -#ifdef CONFIG_SMP - /* Check cpu_callin_map here because that is set - after the timer is started. */ - if (!cpu_isset(cpu, cpu_callin_map)) - continue; -#endif + for_each_online_cpu(cpu) { if (!per_cpu(wd_enabled, cpu)) continue; - if (nmi_count(cpu) - prev_nmi_count[cpu] <= 5) { + if (get_nmi_count(cpu) - prev_nmi_count[cpu] <= 5) { printk(KERN_WARNING "WARNING: CPU#%d: NMI " "appears to be stuck (%d->%d)!\n", cpu, prev_nmi_count[cpu], - nmi_count(cpu)); + get_nmi_count(cpu)); per_cpu(wd_enabled, cpu) = 0; atomic_dec(&nmi_active); } @@ -118,37 +155,53 @@ int __init check_nmi_watchdog(void) if (!atomic_read(&nmi_active)) { kfree(prev_nmi_count); atomic_set(&nmi_active, -1); - return -1; + goto error; } printk("OK.\n"); - /* now that we know it works we can reduce NMI frequency to - something more reasonable; makes a difference in some configs */ + /* + * now that we know it works we can reduce NMI frequency to + * something more reasonable; makes a difference in some configs + */ if (nmi_watchdog == NMI_LOCAL_APIC) nmi_hz = lapic_adjust_nmi_hz(1); kfree(prev_nmi_count); return 0; +error: + if (nmi_watchdog == NMI_IO_APIC && !timer_through_8259) + disable_8259A_irq(0); +#ifdef CONFIG_X86_32 + timer_ack = 0; +#endif + return -1; } static int __init setup_nmi_watchdog(char *str) { - int nmi; + unsigned int nmi; + + if (!strncmp(str, "panic", 5)) { + panic_on_timeout = 1; + str = strchr(str, ','); + if (!str) + return 1; + ++str; + } get_option(&str, &nmi); - if ((nmi >= NMI_INVALID) || (nmi < NMI_NONE)) + if (nmi >= NMI_INVALID) return 0; nmi_watchdog = nmi; return 1; } - __setup("nmi_watchdog=", setup_nmi_watchdog); - -/* Suspend/resume support */ - +/* + * Suspend/resume support + */ #ifdef CONFIG_PM static int nmi_pm_active; /* nmi_active before suspend */ @@ -172,7 +225,6 @@ static int lapic_nmi_resume(struct sys_device *dev) return 0; } - static struct sysdev_class nmi_sysclass = { .name = "lapic_nmi", .resume = lapic_nmi_resume, @@ -188,7 +240,8 @@ static int __init init_lapic_nmi_sysfs(void) { int error; - /* should really be a BUG_ON but b/c this is an + /* + * should really be a BUG_ON but b/c this is an * init call, it just doesn't work. -dcz */ if (nmi_watchdog != NMI_LOCAL_APIC) @@ -202,6 +255,7 @@ static int __init init_lapic_nmi_sysfs(void) error = sysdev_register(&device_lapic_nmi); return error; } + /* must come after the local APIC's device_initcall() */ late_initcall(init_lapic_nmi_sysfs); @@ -223,7 +277,7 @@ void acpi_nmi_enable(void) static void __acpi_nmi_disable(void *__unused) { - apic_write(APIC_LVT0, APIC_DM_NMI | APIC_LVT_MASKED); + apic_write_around(APIC_LVT0, APIC_DM_NMI | APIC_LVT_MASKED); } /* @@ -242,12 +296,13 @@ void setup_apic_nmi_watchdog(void *unused) /* cheap hack to support suspend/resume */ /* if cpu0 is not active neither should the other cpus */ - if ((smp_processor_id() != 0) && (atomic_read(&nmi_active) <= 0)) + if (smp_processor_id() != 0 && atomic_read(&nmi_active) <= 0) return; switch (nmi_watchdog) { case NMI_LOCAL_APIC: - __get_cpu_var(wd_enabled) = 1; /* enable it before to avoid race with handler */ + /* enable it before to avoid race with handler */ + __get_cpu_var(wd_enabled) = 1; if (lapic_watchdog_init(nmi_hz) < 0) { __get_cpu_var(wd_enabled) = 0; return; @@ -262,9 +317,8 @@ void setup_apic_nmi_watchdog(void *unused) void stop_apic_nmi_watchdog(void *unused) { /* only support LOCAL and IO APICs for now */ - if ((nmi_watchdog != NMI_LOCAL_APIC) && - (nmi_watchdog != NMI_IO_APIC)) - return; + if (!nmi_watchdog_active()) + return; if (__get_cpu_var(wd_enabled) == 0) return; if (nmi_watchdog == NMI_LOCAL_APIC) @@ -284,26 +338,26 @@ void stop_apic_nmi_watchdog(void *unused) * since NMIs don't listen to _any_ locks, we have to be extremely * careful not to rely on unsafe variables. The printk might lock * up though, so we have to break up any console locks first ... - * [when there will be more tty-related locks, break them up - * here too!] + * [when there will be more tty-related locks, break them up here too!] */ -static unsigned int - last_irq_sums [NR_CPUS], - alert_counter [NR_CPUS]; +static DEFINE_PER_CPU(unsigned, last_irq_sum); +static DEFINE_PER_CPU(local_t, alert_counter); +static DEFINE_PER_CPU(int, nmi_touch); void touch_nmi_watchdog(void) { - if (nmi_watchdog > 0) { + if (nmi_watchdog_active()) { unsigned cpu; /* - * Just reset the alert counters, (other CPUs might be - * spinning on locks we hold): + * Tell other CPUs to reset their alert counters. We cannot + * do it ourselves because the alert count increase is not + * atomic. */ for_each_present_cpu(cpu) { - if (alert_counter[cpu]) - alert_counter[cpu] = 0; + if (per_cpu(nmi_touch, cpu) != 1) + per_cpu(nmi_touch, cpu) = 1; } } @@ -314,12 +368,9 @@ void touch_nmi_watchdog(void) } EXPORT_SYMBOL(touch_nmi_watchdog); -extern void die_nmi(struct pt_regs *, const char *msg); - notrace __kprobes int nmi_watchdog_tick(struct pt_regs *regs, unsigned reason) { - /* * Since current_thread_info()-> is always on the stack, and we * always switch the stack NMI-atomically, it's safe to use @@ -337,39 +388,45 @@ nmi_watchdog_tick(struct pt_regs *regs, unsigned reason) touched = 1; } + sum = get_timer_irqs(cpu); + + if (__get_cpu_var(nmi_touch)) { + __get_cpu_var(nmi_touch) = 0; + touched = 1; + } + if (cpu_isset(cpu, backtrace_mask)) { static DEFINE_SPINLOCK(lock); /* Serialise the printks */ spin_lock(&lock); - printk("NMI backtrace for cpu %d\n", cpu); + printk(KERN_WARNING "NMI backtrace for cpu %d\n", cpu); dump_stack(); spin_unlock(&lock); cpu_clear(cpu, backtrace_mask); } - /* - * Take the local apic timer and PIT/HPET into account. We don't - * know which one is active, when we have highres/dyntick on - */ - sum = per_cpu(irq_stat, cpu).apic_timer_irqs + - per_cpu(irq_stat, cpu).irq0_irqs; + /* Could check oops_in_progress here too, but it's safer not to */ + if (mce_in_progress()) + touched = 1; /* if the none of the timers isn't firing, this cpu isn't doing much */ - if (!touched && last_irq_sums[cpu] == sum) { + if (!touched && __get_cpu_var(last_irq_sum) == sum) { /* * Ayiee, looks like this CPU is stuck ... * wait a few IRQs (5 seconds) before doing the oops ... */ - alert_counter[cpu]++; - if (alert_counter[cpu] == 5*nmi_hz) + local_inc(&__get_cpu_var(alert_counter)); + if (local_read(&__get_cpu_var(alert_counter)) == 5 * nmi_hz) /* * die_nmi will return ONLY if NOTIFY_STOP happens.. */ - die_nmi(regs, "BUG: NMI Watchdog detected LOCKUP"); + die_nmi("BUG: NMI Watchdog detected LOCKUP", + regs, panic_on_timeout); } else { - last_irq_sums[cpu] = sum; - alert_counter[cpu] = 0; + __get_cpu_var(last_irq_sum) = sum; + local_set(&__get_cpu_var(alert_counter), 0); } + /* see if the nmi watchdog went off */ if (!__get_cpu_var(wd_enabled)) return rc; @@ -378,7 +435,8 @@ nmi_watchdog_tick(struct pt_regs *regs, unsigned reason) rc |= lapic_wd_event(nmi_hz); break; case NMI_IO_APIC: - /* don't know how to accurately check for this. + /* + * don't know how to accurately check for this. * just assume it was a watchdog timer interrupt * This matches the old behaviour. */ @@ -396,7 +454,7 @@ static int unknown_nmi_panic_callback(struct pt_regs *regs, int cpu) char buf[64]; sprintf(buf, "NMI received for unknown reason %02x\n", reason); - die_nmi(regs, buf); + die_nmi(buf, regs, 1); /* Always panic here */ return 0; } @@ -414,32 +472,26 @@ int proc_nmi_enabled(struct ctl_table *table, int write, struct file *file, if (!!old_state == !!nmi_watchdog_enabled) return 0; - if (atomic_read(&nmi_active) < 0 || nmi_watchdog == NMI_DISABLED) { - printk( KERN_WARNING "NMI watchdog is permanently disabled\n"); + if (atomic_read(&nmi_active) < 0 || !nmi_watchdog_active()) { + printk(KERN_WARNING + "NMI watchdog is permanently disabled\n"); return -EIO; } - if (nmi_watchdog == NMI_DEFAULT) { - if (lapic_watchdog_ok()) - nmi_watchdog = NMI_LOCAL_APIC; - else - nmi_watchdog = NMI_IO_APIC; - } - if (nmi_watchdog == NMI_LOCAL_APIC) { if (nmi_watchdog_enabled) enable_lapic_nmi_watchdog(); else disable_lapic_nmi_watchdog(); } else { - printk( KERN_WARNING + printk(KERN_WARNING "NMI watchdog doesn't know what hardware to touch\n"); return -EIO; } return 0; } -#endif +#endif /* CONFIG_SYSCTL */ int do_nmi_callback(struct pt_regs *regs, int cpu) { @@ -462,6 +514,3 @@ void __trigger_all_cpu_backtrace(void) mdelay(1); } } - -EXPORT_SYMBOL(nmi_active); -EXPORT_SYMBOL(nmi_watchdog);