diff options
Diffstat (limited to 'arch/x86_64/kernel/nmi.c')
| -rw-r--r-- | arch/x86_64/kernel/nmi.c | 589 |
1 files changed, 0 insertions, 589 deletions
diff --git a/arch/x86_64/kernel/nmi.c b/arch/x86_64/kernel/nmi.c deleted file mode 100644 index 4e44d6e6b7e..00000000000 --- a/arch/x86_64/kernel/nmi.c +++ /dev/null @@ -1,589 +0,0 @@ -/* - * linux/arch/x86_64/nmi.c - * - * NMI watchdog support on APIC systems - * - * Started by Ingo Molnar <mingo@redhat.com> - * - * Fixes: - * Mikael Pettersson : AMD K7 support for local APIC NMI watchdog. - * Mikael Pettersson : Power Management for local APIC NMI watchdog. - * Pavel Machek and - * Mikael Pettersson : PM converted to driver model. Disable/enable API. - */ - -#include <linux/config.h> -#include <linux/mm.h> -#include <linux/irq.h> -#include <linux/delay.h> -#include <linux/bootmem.h> -#include <linux/smp_lock.h> -#include <linux/interrupt.h> -#include <linux/mc146818rtc.h> -#include <linux/kernel_stat.h> -#include <linux/module.h> -#include <linux/sysdev.h> -#include <linux/nmi.h> -#include <linux/sysctl.h> - -#include <asm/smp.h> -#include <asm/mtrr.h> -#include <asm/mpspec.h> -#include <asm/nmi.h> -#include <asm/msr.h> -#include <asm/proto.h> -#include <asm/kdebug.h> -#include <asm/local.h> - -/* - * lapic_nmi_owner tracks the ownership of the lapic NMI hardware: - * - it may be reserved by some other driver, or not - * - when not reserved by some other driver, it may be used for - * the NMI watchdog, or not - * - * This is maintained separately from nmi_active because the NMI - * watchdog may also be driven from the I/O APIC timer. - */ -static DEFINE_SPINLOCK(lapic_nmi_owner_lock); -static unsigned int lapic_nmi_owner; -#define LAPIC_NMI_WATCHDOG (1<<0) -#define LAPIC_NMI_RESERVED (1<<1) - -/* nmi_active: - * +1: the lapic NMI watchdog is active, but can be disabled - * 0: the lapic NMI watchdog has not been set up, and cannot - * be enabled - * -1: the lapic NMI watchdog is disabled, but can be enabled - */ -int nmi_active; /* oprofile uses this */ -int panic_on_timeout; - -unsigned int nmi_watchdog = NMI_DEFAULT; -static unsigned int nmi_hz = HZ; -static unsigned int nmi_perfctr_msr; /* the MSR to reset in NMI handler */ -static unsigned int nmi_p4_cccr_val; - -/* Note that these events don't tick when the CPU idles. This means - the frequency varies with CPU load. */ - -#define K7_EVNTSEL_ENABLE (1 << 22) -#define K7_EVNTSEL_INT (1 << 20) -#define K7_EVNTSEL_OS (1 << 17) -#define K7_EVNTSEL_USR (1 << 16) -#define K7_EVENT_CYCLES_PROCESSOR_IS_RUNNING 0x76 -#define K7_NMI_EVENT K7_EVENT_CYCLES_PROCESSOR_IS_RUNNING - -#define MSR_P4_MISC_ENABLE 0x1A0 -#define MSR_P4_MISC_ENABLE_PERF_AVAIL (1<<7) -#define MSR_P4_MISC_ENABLE_PEBS_UNAVAIL (1<<12) -#define MSR_P4_PERFCTR0 0x300 -#define MSR_P4_CCCR0 0x360 -#define P4_ESCR_EVENT_SELECT(N) ((N)<<25) -#define P4_ESCR_OS (1<<3) -#define P4_ESCR_USR (1<<2) -#define P4_CCCR_OVF_PMI0 (1<<26) -#define P4_CCCR_OVF_PMI1 (1<<27) -#define P4_CCCR_THRESHOLD(N) ((N)<<20) -#define P4_CCCR_COMPLEMENT (1<<19) -#define P4_CCCR_COMPARE (1<<18) -#define P4_CCCR_REQUIRED (3<<16) -#define P4_CCCR_ESCR_SELECT(N) ((N)<<13) -#define P4_CCCR_ENABLE (1<<12) -/* Set up IQ_COUNTER0 to behave like a clock, by having IQ_CCCR0 filter - CRU_ESCR0 (with any non-null event selector) through a complemented - max threshold. [IA32-Vol3, Section 14.9.9] */ -#define MSR_P4_IQ_COUNTER0 0x30C -#define P4_NMI_CRU_ESCR0 (P4_ESCR_EVENT_SELECT(0x3F)|P4_ESCR_OS|P4_ESCR_USR) -#define P4_NMI_IQ_CCCR0 \ - (P4_CCCR_OVF_PMI0|P4_CCCR_THRESHOLD(15)|P4_CCCR_COMPLEMENT| \ - P4_CCCR_COMPARE|P4_CCCR_REQUIRED|P4_CCCR_ESCR_SELECT(4)|P4_CCCR_ENABLE) - -static __cpuinit inline int nmi_known_cpu(void) -{ - switch (boot_cpu_data.x86_vendor) { - case X86_VENDOR_AMD: - return boot_cpu_data.x86 == 15; - case X86_VENDOR_INTEL: - return boot_cpu_data.x86 == 15; - } - return 0; -} - -/* Run after command line and cpu_init init, but before all other checks */ -void __cpuinit nmi_watchdog_default(void) -{ - if (nmi_watchdog != NMI_DEFAULT) - return; - if (nmi_known_cpu()) - nmi_watchdog = NMI_LOCAL_APIC; - else - nmi_watchdog = NMI_IO_APIC; -} - -#ifdef CONFIG_SMP -/* 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) -{ - volatile int *endflag = data; - local_irq_enable(); - /* 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) - barrier(); -} -#endif - -int __init check_nmi_watchdog (void) -{ - volatile int endflag = 0; - int *counts; - int cpu; - - counts = kmalloc(NR_CPUS * sizeof(int), GFP_KERNEL); - if (!counts) - return -1; - - printk(KERN_INFO "testing NMI watchdog ... "); - - if (nmi_watchdog == NMI_LOCAL_APIC) - smp_call_function(nmi_cpu_busy, (void *)&endflag, 0, 0); - - for (cpu = 0; cpu < NR_CPUS; cpu++) - counts[cpu] = cpu_pda[cpu].__nmi_count; - local_irq_enable(); - mdelay((10*1000)/nmi_hz); // wait 10 ticks - - for (cpu = 0; cpu < NR_CPUS; cpu++) { - if (!cpu_online(cpu)) - continue; - if (cpu_pda[cpu].__nmi_count - counts[cpu] <= 5) { - endflag = 1; - printk("CPU#%d: NMI appears to be stuck (%d->%d)!\n", - cpu, - counts[cpu], - cpu_pda[cpu].__nmi_count); - nmi_active = 0; - lapic_nmi_owner &= ~LAPIC_NMI_WATCHDOG; - nmi_perfctr_msr = 0; - kfree(counts); - return -1; - } - } - endflag = 1; - printk("OK.\n"); - - /* 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 = 1; - - kfree(counts); - return 0; -} - -int __init setup_nmi_watchdog(char *str) -{ - 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) - return 0; - nmi_watchdog = nmi; - return 1; -} - -__setup("nmi_watchdog=", setup_nmi_watchdog); - -static void disable_lapic_nmi_watchdog(void) -{ - if (nmi_active <= 0) - return; - switch (boot_cpu_data.x86_vendor) { - case X86_VENDOR_AMD: - wrmsr(MSR_K7_EVNTSEL0, 0, 0); - break; - case X86_VENDOR_INTEL: - if (boot_cpu_data.x86 == 15) { - wrmsr(MSR_P4_IQ_CCCR0, 0, 0); - wrmsr(MSR_P4_CRU_ESCR0, 0, 0); - } - break; - } - nmi_active = -1; - /* tell do_nmi() and others that we're not active any more */ - nmi_watchdog = 0; -} - -static void enable_lapic_nmi_watchdog(void) -{ - if (nmi_active < 0) { - nmi_watchdog = NMI_LOCAL_APIC; - setup_apic_nmi_watchdog(); - } -} - -int reserve_lapic_nmi(void) -{ - unsigned int old_owner; - - spin_lock(&lapic_nmi_owner_lock); - old_owner = lapic_nmi_owner; - lapic_nmi_owner |= LAPIC_NMI_RESERVED; - spin_unlock(&lapic_nmi_owner_lock); - if (old_owner & LAPIC_NMI_RESERVED) - return -EBUSY; - if (old_owner & LAPIC_NMI_WATCHDOG) - disable_lapic_nmi_watchdog(); - return 0; -} - -void release_lapic_nmi(void) -{ - unsigned int new_owner; - - spin_lock(&lapic_nmi_owner_lock); - new_owner = lapic_nmi_owner & ~LAPIC_NMI_RESERVED; - lapic_nmi_owner = new_owner; - spin_unlock(&lapic_nmi_owner_lock); - if (new_owner & LAPIC_NMI_WATCHDOG) - enable_lapic_nmi_watchdog(); -} - -void disable_timer_nmi_watchdog(void) -{ - if ((nmi_watchdog != NMI_IO_APIC) || (nmi_active <= 0)) - return; - - disable_irq(0); - unset_nmi_callback(); - nmi_active = -1; - nmi_watchdog = NMI_NONE; -} - -void enable_timer_nmi_watchdog(void) -{ - if (nmi_active < 0) { - nmi_watchdog = NMI_IO_APIC; - touch_nmi_watchdog(); - nmi_active = 1; - enable_irq(0); - } -} - -#ifdef CONFIG_PM - -static int nmi_pm_active; /* nmi_active before suspend */ - -static int lapic_nmi_suspend(struct sys_device *dev, u32 state) -{ - nmi_pm_active = nmi_active; - disable_lapic_nmi_watchdog(); - return 0; -} - -static int lapic_nmi_resume(struct sys_device *dev) -{ - if (nmi_pm_active > 0) - enable_lapic_nmi_watchdog(); - return 0; -} - -static struct sysdev_class nmi_sysclass = { - set_kset_name("lapic_nmi"), - .resume = lapic_nmi_resume, - .suspend = lapic_nmi_suspend, -}; - -static struct sys_device device_lapic_nmi = { - .id = 0, - .cls = &nmi_sysclass, -}; - -static int __init init_lapic_nmi_sysfs(void) -{ - int error; - - if (nmi_active == 0 || nmi_watchdog != NMI_LOCAL_APIC) - return 0; - - error = sysdev_class_register(&nmi_sysclass); - if (!error) - error = sysdev_register(&device_lapic_nmi); - return error; -} -/* must come after the local APIC's device_initcall() */ -late_initcall(init_lapic_nmi_sysfs); - -#endif /* CONFIG_PM */ - -/* - * Activate the NMI watchdog via the local APIC. - * Original code written by Keith Owens. - */ - -static void clear_msr_range(unsigned int base, unsigned int n) -{ - unsigned int i; - - for(i = 0; i < n; ++i) - wrmsr(base+i, 0, 0); -} - -static void setup_k7_watchdog(void) -{ - int i; - unsigned int evntsel; - - nmi_perfctr_msr = MSR_K7_PERFCTR0; - - for(i = 0; i < 4; ++i) { - /* Simulator may not support it */ - if (checking_wrmsrl(MSR_K7_EVNTSEL0+i, 0UL)) { - nmi_perfctr_msr = 0; - return; - } - wrmsrl(MSR_K7_PERFCTR0+i, 0UL); - } - - evntsel = K7_EVNTSEL_INT - | K7_EVNTSEL_OS - | K7_EVNTSEL_USR - | K7_NMI_EVENT; - - wrmsr(MSR_K7_EVNTSEL0, evntsel, 0); - wrmsr(MSR_K7_PERFCTR0, -(cpu_khz/nmi_hz*1000), -1); - apic_write(APIC_LVTPC, APIC_DM_NMI); - evntsel |= K7_EVNTSEL_ENABLE; - wrmsr(MSR_K7_EVNTSEL0, evntsel, 0); -} - - -static int setup_p4_watchdog(void) -{ - unsigned int misc_enable, dummy; - - rdmsr(MSR_P4_MISC_ENABLE, misc_enable, dummy); - if (!(misc_enable & MSR_P4_MISC_ENABLE_PERF_AVAIL)) - return 0; - - nmi_perfctr_msr = MSR_P4_IQ_COUNTER0; - nmi_p4_cccr_val = P4_NMI_IQ_CCCR0; -#ifdef CONFIG_SMP - if (smp_num_siblings == 2) - nmi_p4_cccr_val |= P4_CCCR_OVF_PMI1; -#endif - - if (!(misc_enable & MSR_P4_MISC_ENABLE_PEBS_UNAVAIL)) - clear_msr_range(0x3F1, 2); - /* MSR 0x3F0 seems to have a default value of 0xFC00, but current - docs doesn't fully define it, so leave it alone for now. */ - if (boot_cpu_data.x86_model >= 0x3) { - /* MSR_P4_IQ_ESCR0/1 (0x3ba/0x3bb) removed */ - clear_msr_range(0x3A0, 26); - clear_msr_range(0x3BC, 3); - } else { - clear_msr_range(0x3A0, 31); - } - clear_msr_range(0x3C0, 6); - clear_msr_range(0x3C8, 6); - clear_msr_range(0x3E0, 2); - clear_msr_range(MSR_P4_CCCR0, 18); - clear_msr_range(MSR_P4_PERFCTR0, 18); - - wrmsr(MSR_P4_CRU_ESCR0, P4_NMI_CRU_ESCR0, 0); - wrmsr(MSR_P4_IQ_CCCR0, P4_NMI_IQ_CCCR0 & ~P4_CCCR_ENABLE, 0); - Dprintk("setting P4_IQ_COUNTER0 to 0x%08lx\n", -(cpu_khz/nmi_hz*1000)); - wrmsr(MSR_P4_IQ_COUNTER0, -(cpu_khz/nmi_hz*1000), -1); - apic_write(APIC_LVTPC, APIC_DM_NMI); - wrmsr(MSR_P4_IQ_CCCR0, nmi_p4_cccr_val, 0); - return 1; -} - -void setup_apic_nmi_watchdog(void) -{ - switch (boot_cpu_data.x86_vendor) { - case X86_VENDOR_AMD: - if (boot_cpu_data.x86 != 15) - return; - if (strstr(boot_cpu_data.x86_model_id, "Screwdriver")) - return; - setup_k7_watchdog(); - break; - case X86_VENDOR_INTEL: - if (boot_cpu_data.x86 != 15) - return; - if (!setup_p4_watchdog()) - return; - break; - - default: - return; - } - lapic_nmi_owner = LAPIC_NMI_WATCHDOG; - nmi_active = 1; -} - -/* - * the best way to detect whether a CPU has a 'hard lockup' problem - * is to check it's local APIC timer IRQ counts. If they are not - * changing then that CPU has some problem. - * - * as these watchdog NMI IRQs are generated on every CPU, we only - * have to check the current processor. - */ - -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) -{ - int i; - - /* - * Tell other CPUs to reset their alert counters. We cannot - * do it ourselves because the alert count increase is not - * atomic. - */ - for (i = 0; i < NR_CPUS; i++) - per_cpu(nmi_touch, i) = 1; -} - -void nmi_watchdog_tick (struct pt_regs * regs, unsigned reason) -{ - int sum; - int touched = 0; - - sum = read_pda(apic_timer_irqs); - if (__get_cpu_var(nmi_touch)) { - __get_cpu_var(nmi_touch) = 0; - touched = 1; - } - 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 ... - */ - local_inc(&__get_cpu_var(alert_counter)); - if (local_read(&__get_cpu_var(alert_counter)) == 5*nmi_hz) { - if (notify_die(DIE_NMI, "nmi", regs, reason, 2, SIGINT) - == NOTIFY_STOP) { - local_set(&__get_cpu_var(alert_counter), 0); - return; - } - die_nmi("NMI Watchdog detected LOCKUP on CPU%d", regs); - } - } else { - __get_cpu_var(last_irq_sum) = sum; - local_set(&__get_cpu_var(alert_counter), 0); - } - if (nmi_perfctr_msr) { - if (nmi_perfctr_msr == MSR_P4_IQ_COUNTER0) { - /* - * P4 quirks: - * - An overflown perfctr will assert its interrupt - * until the OVF flag in its CCCR is cleared. - * - LVTPC is masked on interrupt and must be - * unmasked by the LVTPC handler. - */ - wrmsr(MSR_P4_IQ_CCCR0, nmi_p4_cccr_val, 0); - apic_write(APIC_LVTPC, APIC_DM_NMI); - } - wrmsr(nmi_perfctr_msr, -(cpu_khz/nmi_hz*1000), -1); - } -} - -static int dummy_nmi_callback(struct pt_regs * regs, int cpu) -{ - return 0; -} - -static nmi_callback_t nmi_callback = dummy_nmi_callback; - -asmlinkage void do_nmi(struct pt_regs * regs, long error_code) -{ - int cpu = safe_smp_processor_id(); - - nmi_enter(); - add_pda(__nmi_count,1); - if (!nmi_callback(regs, cpu)) - default_do_nmi(regs); - nmi_exit(); -} - -void set_nmi_callback(nmi_callback_t callback) -{ - nmi_callback = callback; -} - -void unset_nmi_callback(void) -{ - nmi_callback = dummy_nmi_callback; -} - -#ifdef CONFIG_SYSCTL - -static int unknown_nmi_panic_callback(struct pt_regs *regs, int cpu) -{ - unsigned char reason = get_nmi_reason(); - char buf[64]; - - if (!(reason & 0xc0)) { - sprintf(buf, "NMI received for unknown reason %02x\n", reason); - die_nmi(buf,regs); - } - return 0; -} - -/* - * proc handler for /proc/sys/kernel/unknown_nmi_panic - */ -int proc_unknown_nmi_panic(struct ctl_table *table, int write, struct file *file, - void __user *buffer, size_t *length, loff_t *ppos) -{ - int old_state; - - old_state = unknown_nmi_panic; - proc_dointvec(table, write, file, buffer, length, ppos); - if (!!old_state == !!unknown_nmi_panic) - return 0; - - if (unknown_nmi_panic) { - if (reserve_lapic_nmi() < 0) { - unknown_nmi_panic = 0; - return -EBUSY; - } else { - set_nmi_callback(unknown_nmi_panic_callback); - } - } else { - release_lapic_nmi(); - unset_nmi_callback(); - } - return 0; -} - -#endif - -EXPORT_SYMBOL(nmi_active); -EXPORT_SYMBOL(nmi_watchdog); -EXPORT_SYMBOL(reserve_lapic_nmi); -EXPORT_SYMBOL(release_lapic_nmi); -EXPORT_SYMBOL(disable_timer_nmi_watchdog); -EXPORT_SYMBOL(enable_timer_nmi_watchdog); -EXPORT_SYMBOL(touch_nmi_watchdog); |