diff options
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/i386/kernel/cpu/Makefile | 2 | ||||
| -rw-r--r-- | arch/i386/kernel/cpu/perfctr-watchdog.c | 658 | ||||
| -rw-r--r-- | arch/i386/kernel/nmi.c | 829 |
3 files changed, 713 insertions, 776 deletions
diff --git a/arch/i386/kernel/cpu/Makefile b/arch/i386/kernel/cpu/Makefile index 5fb1a756043..74f27a463db 100644 --- a/arch/i386/kernel/cpu/Makefile +++ b/arch/i386/kernel/cpu/Makefile @@ -17,3 +17,5 @@ obj-$(CONFIG_X86_MCE) += mcheck/ obj-$(CONFIG_MTRR) += mtrr/ obj-$(CONFIG_CPU_FREQ) += cpufreq/ + +obj-$(CONFIG_X86_LOCAL_APIC) += perfctr-watchdog.o diff --git a/arch/i386/kernel/cpu/perfctr-watchdog.c b/arch/i386/kernel/cpu/perfctr-watchdog.c new file mode 100644 index 00000000000..2b04c8f1db6 --- /dev/null +++ b/arch/i386/kernel/cpu/perfctr-watchdog.c @@ -0,0 +1,658 @@ +/* local apic based NMI watchdog for various CPUs. + This file also handles reservation of performance counters for coordination + with other users (like oprofile). + + Note that these events normally don't tick when the CPU idles. This means + the frequency varies with CPU load. + + Original code for K7/P6 written by Keith Owens */ + +#include <linux/percpu.h> +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/bitops.h> +#include <linux/smp.h> +#include <linux/nmi.h> +#include <asm/apic.h> +#include <asm/intel_arch_perfmon.h> + +struct nmi_watchdog_ctlblk { + unsigned int cccr_msr; + unsigned int perfctr_msr; /* the MSR to reset in NMI handler */ + unsigned int evntsel_msr; /* the MSR to select the events to handle */ +}; + +/* Interface defining a CPU specific perfctr watchdog */ +struct wd_ops { + int (*reserve)(void); + void (*unreserve)(void); + int (*setup)(unsigned nmi_hz); + void (*rearm)(struct nmi_watchdog_ctlblk *wd, unsigned nmi_hz); + void (*stop)(void *); + unsigned perfctr; + unsigned evntsel; + u64 checkbit; +}; + +static struct wd_ops *wd_ops; + +/* this number is calculated from Intel's MSR_P4_CRU_ESCR5 register and it's + * offset from MSR_P4_BSU_ESCR0. It will be the max for all platforms (for now) + */ +#define NMI_MAX_COUNTER_BITS 66 + +/* perfctr_nmi_owner tracks the ownership of the perfctr registers: + * evtsel_nmi_owner tracks the ownership of the event selection + * - different performance counters/ event selection may be reserved for + * different subsystems this reservation system just tries to coordinate + * things a little + */ +static DECLARE_BITMAP(perfctr_nmi_owner, NMI_MAX_COUNTER_BITS); +static DECLARE_BITMAP(evntsel_nmi_owner, NMI_MAX_COUNTER_BITS); + +static DEFINE_PER_CPU(struct nmi_watchdog_ctlblk, nmi_watchdog_ctlblk); + +/* converts an msr to an appropriate reservation bit */ +static inline unsigned int nmi_perfctr_msr_to_bit(unsigned int msr) +{ + return wd_ops ? msr - wd_ops->perfctr : 0; +} + +/* converts an msr to an appropriate reservation bit */ +/* returns the bit offset of the event selection register */ +static inline unsigned int nmi_evntsel_msr_to_bit(unsigned int msr) +{ + return wd_ops ? msr - wd_ops->evntsel : 0; +} + +/* checks for a bit availability (hack for oprofile) */ +int avail_to_resrv_perfctr_nmi_bit(unsigned int counter) +{ + BUG_ON(counter > NMI_MAX_COUNTER_BITS); + + return (!test_bit(counter, perfctr_nmi_owner)); +} + +/* checks the an msr for availability */ +int avail_to_resrv_perfctr_nmi(unsigned int msr) +{ + unsigned int counter; + + counter = nmi_perfctr_msr_to_bit(msr); + BUG_ON(counter > NMI_MAX_COUNTER_BITS); + + return (!test_bit(counter, perfctr_nmi_owner)); +} + +int reserve_perfctr_nmi(unsigned int msr) +{ + unsigned int counter; + + counter = nmi_perfctr_msr_to_bit(msr); + BUG_ON(counter > NMI_MAX_COUNTER_BITS); + + if (!test_and_set_bit(counter, perfctr_nmi_owner)) + return 1; + return 0; +} + +void release_perfctr_nmi(unsigned int msr) +{ + unsigned int counter; + + counter = nmi_perfctr_msr_to_bit(msr); + BUG_ON(counter > NMI_MAX_COUNTER_BITS); + + clear_bit(counter, perfctr_nmi_owner); +} + +int reserve_evntsel_nmi(unsigned int msr) +{ + unsigned int counter; + + counter = nmi_evntsel_msr_to_bit(msr); + BUG_ON(counter > NMI_MAX_COUNTER_BITS); + + if (!test_and_set_bit(counter, evntsel_nmi_owner)) + return 1; + return 0; +} + +void release_evntsel_nmi(unsigned int msr) +{ + unsigned int counter; + + counter = nmi_evntsel_msr_to_bit(msr); + BUG_ON(counter > NMI_MAX_COUNTER_BITS); + + clear_bit(counter, evntsel_nmi_owner); +} + +EXPORT_SYMBOL(avail_to_resrv_perfctr_nmi); +EXPORT_SYMBOL(avail_to_resrv_perfctr_nmi_bit); +EXPORT_SYMBOL(reserve_perfctr_nmi); +EXPORT_SYMBOL(release_perfctr_nmi); +EXPORT_SYMBOL(reserve_evntsel_nmi); +EXPORT_SYMBOL(release_evntsel_nmi); + +void disable_lapic_nmi_watchdog(void) +{ + BUG_ON(nmi_watchdog != NMI_LOCAL_APIC); + + if (atomic_read(&nmi_active) <= 0) + return; + + on_each_cpu(wd_ops->stop, NULL, 0, 1); + wd_ops->unreserve(); + + BUG_ON(atomic_read(&nmi_active) != 0); +} + +void enable_lapic_nmi_watchdog(void) +{ + BUG_ON(nmi_watchdog != NMI_LOCAL_APIC); + + /* are we already enabled */ + if (atomic_read(&nmi_active) != 0) + return; + + /* are we lapic aware */ + if (!wd_ops) + return; + if (!wd_ops->reserve()) { + printk(KERN_ERR "NMI watchdog: cannot reserve perfctrs\n"); + return; + } + + on_each_cpu(setup_apic_nmi_watchdog, NULL, 0, 1); + touch_nmi_watchdog(); +} + +/* + * Activate the NMI watchdog via the local APIC. + */ + +static unsigned int adjust_for_32bit_ctr(unsigned int hz) +{ + u64 counter_val; + unsigned int retval = hz; + + /* + * On Intel CPUs with P6/ARCH_PERFMON only 32 bits in the counter + * are writable, with higher bits sign extending from bit 31. + * So, we can only program the counter with 31 bit values and + * 32nd bit should be 1, for 33.. to be 1. + * Find the appropriate nmi_hz + */ + counter_val = (u64)cpu_khz * 1000; + do_div(counter_val, retval); + if (counter_val > 0x7fffffffULL) { + u64 count = (u64)cpu_khz * 1000; + do_div(count, 0x7fffffffUL); + retval = count + 1; + } + return retval; +} + +static void +write_watchdog_counter(unsigned int perfctr_msr, const char *descr, unsigned nmi_hz) +{ + u64 count = (u64)cpu_khz * 1000; + + do_div(count, nmi_hz); + if(descr) + Dprintk("setting %s to -0x%08Lx\n", descr, count); + wrmsrl(perfctr_msr, 0 - count); +} + +static void write_watchdog_counter32(unsigned int perfctr_msr, + const char *descr, unsigned nmi_hz) +{ + u64 count = (u64)cpu_khz * 1000; + + do_div(count, nmi_hz); + if(descr) + Dprintk("setting %s to -0x%08Lx\n", descr, count); + wrmsr(perfctr_msr, (u32)(-count), 0); +} + +/* AMD K7/K8/Family10h/Family11h support. AMD keeps this interface + nicely stable so there is not much variety */ + +#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 + +static int setup_k7_watchdog(unsigned nmi_hz) +{ + unsigned int perfctr_msr, evntsel_msr; + unsigned int evntsel; + struct nmi_watchdog_ctlblk *wd = &__get_cpu_var(nmi_watchdog_ctlblk); + + perfctr_msr = MSR_K7_PERFCTR0; + evntsel_msr = MSR_K7_EVNTSEL0; + + wrmsrl(perfctr_msr, 0UL); + + evntsel = K7_EVNTSEL_INT + | K7_EVNTSEL_OS + | K7_EVNTSEL_USR + | K7_NMI_EVENT; + + /* setup the timer */ + wrmsr(evntsel_msr, evntsel, 0); + write_watchdog_counter(perfctr_msr, "K7_PERFCTR0",nmi_hz); + apic_write(APIC_LVTPC, APIC_DM_NMI); + evntsel |= K7_EVNTSEL_ENABLE; + wrmsr(evntsel_msr, evntsel, 0); + + wd->perfctr_msr = perfctr_msr; + wd->evntsel_msr = evntsel_msr; + wd->cccr_msr = 0; //unused + return 1; +} + +static void single_msr_stop_watchdog(void *arg) +{ + struct nmi_watchdog_ctlblk *wd = &__get_cpu_var(nmi_watchdog_ctlblk); + + wrmsr(wd->evntsel_msr, 0, 0); +} + +static int single_msr_reserve(void) +{ + if (!reserve_perfctr_nmi(wd_ops->perfctr)) + return 0; + + if (!reserve_evntsel_nmi(wd_ops->evntsel)) { + release_perfctr_nmi(wd_ops->perfctr); + return 0; + } + return 1; +} + +static void single_msr_unreserve(void) +{ + release_evntsel_nmi(wd_ops->perfctr); + release_perfctr_nmi(wd_ops->evntsel); +} + +static void single_msr_rearm(struct nmi_watchdog_ctlblk *wd, unsigned nmi_hz) +{ + /* start the cycle over again */ + write_watchdog_counter(wd->perfctr_msr, NULL, nmi_hz); +} + +static struct wd_ops k7_wd_ops = { + .reserve = single_msr_reserve, + .unreserve = single_msr_unreserve, + .setup = setup_k7_watchdog, + .rearm = single_msr_rearm, + .stop = single_msr_stop_watchdog, + .perfctr = MSR_K7_PERFCTR0, + .evntsel = MSR_K7_EVNTSEL0, + .checkbit = 1ULL<<63, +}; + +/* Intel Model 6 (PPro+,P2,P3,P-M,Core1) */ + +#define P6_EVNTSEL0_ENABLE (1 << 22) +#define P6_EVNTSEL_INT (1 << 20) +#define P6_EVNTSEL_OS (1 << 17) +#define P6_EVNTSEL_USR (1 << 16) +#define P6_EVENT_CPU_CLOCKS_NOT_HALTED 0x79 +#define P6_NMI_EVENT P6_EVENT_CPU_CLOCKS_NOT_HALTED + +static int setup_p6_watchdog(unsigned nmi_hz) +{ + unsigned int perfctr_msr, evntsel_msr; + unsigned int evntsel; + struct nmi_watchdog_ctlblk *wd = &__get_cpu_var(nmi_watchdog_ctlblk); + + perfctr_msr = MSR_P6_PERFCTR0; + evntsel_msr = MSR_P6_EVNTSEL0; + + wrmsrl(perfctr_msr, 0UL); + + evntsel = P6_EVNTSEL_INT + | P6_EVNTSEL_OS + | P6_EVNTSEL_USR + | P6_NMI_EVENT; + + /* setup the timer */ + wrmsr(evntsel_msr, evntsel, 0); + nmi_hz = adjust_for_32bit_ctr(nmi_hz); + write_watchdog_counter32(perfctr_msr, "P6_PERFCTR0",nmi_hz); + apic_write(APIC_LVTPC, APIC_DM_NMI); + evntsel |= P6_EVNTSEL0_ENABLE; + wrmsr(evntsel_msr, evntsel, 0); + + wd->perfctr_msr = perfctr_msr; + wd->evntsel_msr = evntsel_msr; + wd->cccr_msr = 0; //unused + return 1; +} + +static void p6_rearm(struct nmi_watchdog_ctlblk *wd, unsigned nmi_hz) +{ + /* P6 based Pentium M need to re-unmask + * the apic vector but it doesn't hurt + * other P6 variant. + * ArchPerfom/Core Duo also needs this */ + apic_write(APIC_LVTPC, APIC_DM_NMI); + /* P6/ARCH_PERFMON has 32 bit counter write */ + write_watchdog_counter32(wd->perfctr_msr, NULL,nmi_hz); +} + +static struct wd_ops p6_wd_ops = { + .reserve = single_msr_reserve, + .unreserve = single_msr_unreserve, + .setup = setup_p6_watchdog, + .rearm = p6_rearm, + .stop = single_msr_stop_watchdog, + .perfctr = MSR_P6_PERFCTR0, + .evntsel = MSR_P6_EVNTSEL0, + .checkbit = 1ULL<<39, +}; + +/* Intel P4 performance counters. By far the most complicated of all. */ + +#define MSR_P4_MISC_ENABLE_PERF_AVAIL (1<<7) +#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) +#define P4_CCCR_OVF (1<<31) + +/* 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] */ + +static int setup_p4_watchdog(unsigned nmi_hz) +{ + unsigned int perfctr_msr, evntsel_msr, cccr_msr; + unsigned int evntsel, cccr_val; + unsigned int misc_enable, dummy; + unsigned int ht_num; + struct nmi_watchdog_ctlblk *wd = &__get_cpu_var(nmi_watchdog_ctlblk); + + rdmsr(MSR_IA32_MISC_ENABLE, misc_enable, dummy); + if (!(misc_enable & MSR_P4_MISC_ENABLE_PERF_AVAIL)) + return 0; + +#ifdef CONFIG_SMP + /* detect which hyperthread we are on */ + if (smp_num_siblings == 2) { + unsigned int ebx, apicid; + + ebx = cpuid_ebx(1); + apicid = (ebx >> 24) & 0xff; + ht_num = apicid & 1; + } else +#endif + ht_num = 0; + + /* performance counters are shared resources + * assign each hyperthread its own set + * (re-use the ESCR0 register, seems safe + * and keeps the cccr_val the same) + */ + if (!ht_num) { + /* logical cpu 0 */ + perfctr_msr = MSR_P4_IQ_PERFCTR0; + evntsel_msr = MSR_P4_CRU_ESCR0; + cccr_msr = MSR_P4_IQ_CCCR0; + cccr_val = P4_CCCR_OVF_PMI0 | P4_CCCR_ESCR_SELECT(4); + } else { + /* logical cpu 1 */ + perfctr_msr = MSR_P4_IQ_PERFCTR1; + evntsel_msr = MSR_P4_CRU_ESCR0; + cccr_msr = MSR_P4_IQ_CCCR1; + cccr_val = P4_CCCR_OVF_PMI1 | P4_CCCR_ESCR_SELECT(4); + } + + evntsel = P4_ESCR_EVENT_SELECT(0x3F) + | P4_ESCR_OS + | P4_ESCR_USR; + + cccr_val |= P4_CCCR_THRESHOLD(15) + | P4_CCCR_COMPLEMENT + | P4_CCCR_COMPARE + | P4_CCCR_REQUIRED; + + wrmsr(evntsel_msr, evntsel, 0); + wrmsr(cccr_msr, cccr_val, 0); + write_watchdog_counter(perfctr_msr, "P4_IQ_COUNTER0", nmi_hz); + apic_write(APIC_LVTPC, APIC_DM_NMI); + cccr_val |= P4_CCCR_ENABLE; + wrmsr(cccr_msr, cccr_val, 0); + wd->perfctr_msr = perfctr_msr; + wd->evntsel_msr = evntsel_msr; + wd->cccr_msr = cccr_msr; + return 1; +} + +static void stop_p4_watchdog(void *arg) +{ + struct nmi_watchdog_ctlblk *wd = &__get_cpu_var(nmi_watchdog_ctlblk); + wrmsr(wd->cccr_msr, 0, 0); + wrmsr(wd->evntsel_msr, 0, 0); +} + +static int p4_reserve(void) +{ + if (!reserve_perfctr_nmi(MSR_P4_IQ_PERFCTR0)) + return 0; +#ifdef CONFIG_SMP + if (smp_num_siblings > 1 && !reserve_perfctr_nmi(MSR_P4_IQ_PERFCTR1)) + goto fail1; +#endif + if (!reserve_evntsel_nmi(MSR_P4_CRU_ESCR0)) + goto fail2; + /* RED-PEN why is ESCR1 not reserved here? */ + return 1; + fail2: +#ifdef CONFIG_SMP + if (smp_num_siblings > 1) + release_perfctr_nmi(MSR_P4_IQ_PERFCTR1); + fail1: +#endif + release_perfctr_nmi(MSR_P4_IQ_PERFCTR0); + return 0; +} + +static void p4_unreserve(void) +{ +#ifdef CONFIG_SMP + if (smp_num_siblings > 1) + release_evntsel_nmi(MSR_P4_IQ_PERFCTR1); +#endif + release_evntsel_nmi(MSR_P4_IQ_PERFCTR0); + release_perfctr_nmi(MSR_P4_CRU_ESCR0); +} + +static void p4_rearm(struct nmi_watchdog_ctlblk *wd, unsigned nmi_hz) +{ + unsigned dummy; + /* + * 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. + */ + rdmsrl(wd->cccr_msr, dummy); + dummy &= ~P4_CCCR_OVF; + wrmsrl(wd->cccr_msr, dummy); + apic_write(APIC_LVTPC, APIC_DM_NMI); + /* start the cycle over again */ + write_watchdog_counter(wd->perfctr_msr, NULL, nmi_hz); +} + +static struct wd_ops p4_wd_ops = { + .reserve = p4_reserve, + .unreserve = p4_unreserve, + .setup = setup_p4_watchdog, + .rearm = p4_rearm, + .stop = stop_p4_watchdog, + /* RED-PEN this is wrong for the other sibling */ + .perfctr = MSR_P4_BPU_PERFCTR0, + .evntsel = MSR_P4_BSU_ESCR0, + .checkbit = 1ULL<<39, +}; + +/* Watchdog using the Intel architected PerfMon. Used for Core2 and hopefully + all future Intel CPUs. */ + +#define ARCH_PERFMON_NMI_EVENT_SEL ARCH_PERFMON_UNHALTED_CORE_CYCLES_SEL +#define ARCH_PERFMON_NMI_EVENT_UMASK ARCH_PERFMON_UNHALTED_CORE_CYCLES_UMASK + +static int setup_intel_arch_watchdog(unsigned nmi_hz) +{ + unsigned int ebx; + union cpuid10_eax eax; + unsigned int unused; + unsigned int perfctr_msr, evntsel_msr; + unsigned int evntsel; + struct nmi_watchdog_ctlblk *wd = &__get_cpu_var(nmi_watchdog_ctlblk); + + /* + * Check whether the Architectural PerfMon supports + * Unhalted Core Cycles Event or not. + * NOTE: Corresponding bit = 0 in ebx indicates event present. + */ + cpuid(10, &(eax.full), &ebx, &unused, &unused); + if ((eax.split.mask_length < (ARCH_PERFMON_UNHALTED_CORE_CYCLES_INDEX+1)) || + (ebx & ARCH_PERFMON_UNHALTED_CORE_CYCLES_PRESENT)) + return 0; + + perfctr_msr = MSR_ARCH_PERFMON_PERFCTR1; + evntsel_msr = MSR_ARCH_PERFMON_EVENTSEL1; + + wrmsrl(perfctr_msr, 0UL); + + evntsel = ARCH_PERFMON_EVENTSEL_INT + | ARCH_PERFMON_EVENTSEL_OS + | ARCH_PERFMON_EVENTSEL_USR + | ARCH_PERFMON_NMI_EVENT_SEL + | ARCH_PERFMON_NMI_EVENT_UMASK; + + /* setup the timer */ + wrmsr(evntsel_msr, evntsel, 0); + nmi_hz = adjust_for_32bit_ctr(nmi_hz); + write_watchdog_counter32(perfctr_msr, "INTEL_ARCH_PERFCTR0", nmi_hz); + apic_write(APIC_LVTPC, APIC_DM_NMI); + evntsel |= ARCH_PERFMON_EVENTSEL0_ENABLE; + wrmsr(evntsel_msr, evntsel, 0); + + wd->perfctr_msr = perfctr_msr; + wd->evntsel_msr = evntsel_msr; + wd->cccr_msr = 0; //unused + wd_ops->checkbit = 1ULL << (eax.split.bit_width - 1); + return 1; +} + +static struct wd_ops intel_arch_wd_ops = { + .reserve = single_msr_reserve, + .unreserve = single_msr_unreserve, + .setup = setup_intel_arch_watchdog, + .rearm = p6_rearm, + .stop = single_msr_stop_watchdog, + .perfctr = MSR_ARCH_PERFMON_PERFCTR0, + .evntsel = MSR_ARCH_PERFMON_EVENTSEL0, +}; + +static void probe_nmi_watchdog(void) +{ + switch (boot_cpu_data.x86_vendor) { + case X86_VENDOR_AMD: + if (boot_cpu_data.x86 != 6 && boot_cpu_data.x86 != 15 && + boot_cpu_data.x86 != 16) + return; + wd_ops = &k7_wd_ops; + break; + case X86_VENDOR_INTEL: + if (cpu_has(&boot_cpu_data, X86_FEATURE_ARCH_PERFMON)) { + wd_ops = &intel_arch_wd_ops; + break; + } + switch (boot_cpu_data.x86) { + case 6: + if (boot_cpu_data.x86_model > 0xd) + return; + + wd_ops = &p6_wd_ops; + break; + case 15: + if (boot_cpu_data.x86_model > 0x4) + return; + + wd_ops = &p4_wd_ops; + break; + default: + return; + } + break; + } +} + +/* Interface to nmi.c */ + +int lapic_watchdog_init(unsigned nmi_hz) +{ + if (!wd_ops) { + probe_nmi_watchdog(); + if (!wd_ops) + return -1; + } + + if (!(wd_ops->setup(nmi_hz))) { + printk(KERN_ERR "Cannot setup NMI watchdog on CPU %d\n", + raw_smp_processor_id()); + return -1; + } + + return 0; +} + +void lapic_watchdog_stop(void) +{ + if (wd_ops) + wd_ops->stop(NULL); +} + +unsigned lapic_adjust_nmi_hz(unsigned hz) +{ + struct nmi_watchdog_ctlblk *wd = &__get_cpu_var(nmi_watchdog_ctlblk); + if (wd->perfctr_msr == MSR_P6_PERFCTR0 || + wd->perfctr_msr == MSR_ARCH_PERFMON_PERFCTR1) + hz = adjust_for_32bit_ctr(hz); + return hz; +} + +int lapic_wd_event(unsigned nmi_hz) +{ + struct nmi_watchdog_ctlblk *wd = &__get_cpu_var(nmi_watchdog_ctlblk); + u64 ctr; + rdmsrl(wd->perfctr_msr, ctr); + if (ctr & wd_ops->checkbit) { /* perfctr still running? */ + return 0; + } + wd_ops->rearm(wd, nmi_hz); + return 1; +} + +int lapic_watchdog_ok(void) +{ + return wd_ops != NULL; +} diff --git a/arch/i386/kernel/nmi.c b/arch/i386/kernel/nmi.c index 2dec1b10573..33cf2f3c444 100644 --- a/arch/i386/kernel/nmi.c +++ b/arch/i386/kernel/nmi.c @@ -20,7 +20,6 @@ #include <linux/sysdev.h> #include <linux/sysctl.h> #include <linux/percpu.h> -#include <linux/dmi.h> #include <linux/kprobes.h> #include <linux/cpumask.h> #include <linux/kernel_stat.h> @@ -28,30 +27,14 @@ #include <asm/smp.h> #include <asm/nmi.h> #include <asm/kdebug.h> -#include <asm/intel_arch_perfmon.h> #include "mach_traps.h" int unknown_nmi_panic; int nmi_watchdog_enabled; -/* perfctr_nmi_owner tracks the ownership of the perfctr registers: - * evtsel_nmi_owner tracks the ownership of the event selection - * - different performance counters/ event selection may be reserved for - * different subsystems this reservation system just tries to coordinate - * things a little - */ - -/* this number is calculated from Intel's MSR_P4_CRU_ESCR5 register and it's - * offset from MSR_P4_BSU_ESCR0. It will be the max for all platforms (for now) - */ -#define NMI_MAX_COUNTER_BITS 66 -#define NMI_MAX_COUNTER_LONGS BITS_TO_LONGS(NMI_MAX_COUNTER_BITS) - -static DEFINE_PER_CPU(unsigned long, perfctr_nmi_owner[NMI_MAX_COUNTER_LONGS]); -static DEFINE_PER_CPU(unsigned long, evntsel_nmi_owner[NMI_MAX_COUNTER_LONGS]); - static cpumask_t backtrace_mask = CPU_MASK_NONE; + /* nmi_active: * >0: the lapic NMI watchdog is active, but can be disabled * <0: the lapic NMI watchdog has not been set up, and cannot @@ -63,203 +46,11 @@ atomic_t nmi_active = ATOMIC_INIT(0); /* oprofile uses this */ unsigned int nmi_watchdog = NMI_DEFAULT; static unsigned int nmi_hz = HZ; -struct nmi_watchdog_ctlblk { - int enabled; - u64 check_bit; - unsigned int cccr_msr; - unsigned int perfctr_msr; /* the MSR to reset in NMI handler */ - unsigned int evntsel_msr; /* the MSR to select the events to handle */ -}; -static DEFINE_PER_CPU(struct nmi_watchdog_ctlblk, nmi_watchdog_ctlblk); +static DEFINE_PER_CPU(short, wd_enabled); /* local prototypes */ static int unknown_nmi_panic_callback(struct pt_regs *regs, int cpu); -/* converts an msr to an appropriate reservation bit */ -static inline unsigned int nmi_perfctr_msr_to_bit(unsigned int msr) -{ - /* returns the bit offset of the performance counter register */ - switch (boot_cpu_data.x86_vendor) { - case X86_VENDOR_AMD: - return (msr - MSR_K7_PERFCTR0); - case X86_VENDOR_INTEL: - if (cpu_has(&boot_cpu_data, X86_FEATURE_ARCH_PERFMON)) - return (msr - MSR_ARCH_PERFMON_PERFCTR0); - - switch (boot_cpu_data.x86) { - case 6: - return (msr - MSR_P6_PERFCTR0); - case 15: - return (msr - MSR_P4_BPU_PERFCTR0); - } - } - return 0; -} - -/* converts an msr to an appropriate reservation bit */ -static inline unsigned int nmi_evntsel_msr_to_bit(unsigned int msr) -{ - /* returns the bit offset of the event selection register */ - switch (boot_cpu_data.x86_vendor) { - case X86_VENDOR_AMD: - return (msr - MSR_K7_EVNTSEL0); - case X86_VENDOR_INTEL: - if (cpu_has(&boot_cpu_data, X86_FEATURE_ARCH_PERFMON)) - return (msr - MSR_ARCH_PERFMON_EVENTSEL0); - - switch (boot_cpu_data.x86) { - case 6: - return (msr - MSR_P6_EVNTSEL0); - case 15: - return (msr - MSR_P4_BSU_ESCR0); - } - } - return 0; -} - -/* checks for a bit availability (hack for oprofile) */ -int avail_to_resrv_perfctr_nmi_bit(unsigned int counter) -{ - int cpu; - BUG_ON(counter > NMI_MAX_COUNTER_BITS); - for_each_possible_cpu (cpu) { - if (test_bit(counter, &per_cpu(perfctr_nmi_owner, cpu)[0])) - return 0; - } - return 1; -} - -/* checks the an msr for availability */ -int avail_to_resrv_perfctr_nmi(unsigned int msr) -{ - unsigned int counter; - int cpu; - - counter = nmi_perfctr_msr_to_bit(msr); - BUG_ON(counter > NMI_MAX_COUNTER_BITS); - - for_each_possible_cpu (cpu) { - if (test_bit(counter, &per_cpu(perfctr_nmi_owner, cpu)[0])) - return 0; - } - return 1; -} - -static int __reserve_perfctr_nmi(int cpu, unsigned int msr) -{ - unsigned int counter; - if (cpu < 0) - cpu = smp_processor_id(); - - counter = nmi_perfctr_msr_to_bit(msr); - BUG_ON(counter > NMI_MAX_COUNTER_BITS); - - if (!test_and_set_bit(counter, &per_cpu(perfctr_nmi_owner, cpu)[0])) - return 1; - return 0; -} - -static void __release_perfctr_nmi(int cpu, unsigned int msr) -{ - unsigned int counter; - if (cpu < 0) - cpu = smp_processor_id(); - - counter = nmi_perfctr_msr_to_bit(msr); - BUG_ON(counter > NMI_MAX_COUNTER_BITS); - - clear_bit(counter, &per_cpu(perfctr_nmi_owner, cpu)[0]); -} - -int reserve_perfctr_nmi(unsigned int msr) -{ - int cpu, i; - for_each_possible_cpu (cpu) { - if (!__reserve_perfctr_nmi(cpu, msr)) { - for_each_possible_cpu (i) { - if (i >= cpu) - break; - __release_perfctr_nmi(i, msr); - } - return 0; - } - } - return 1; -} - -void release_perfctr_nmi(unsigned int msr) -{ - int cpu; - for_each_possible_cpu (cpu) { - __release_perfctr_nmi(cpu, msr); - } -} - -int __reserve_evntsel_nmi(int cpu, unsigned int msr) -{ - unsigned int counter; - if (cpu < 0) - cpu = smp_processor_id(); - - counter = nmi_evntsel_msr_to_bit(msr); - BUG_ON(counter > NMI_MAX_COUNTER_BITS); - - if (!test_and_set_bit(counter, &per_cpu(evntsel_nmi_owner, cpu)[0])) - return 1; - return 0; -} - -static void __release_evntsel_nmi(int cpu, unsigned int msr) -{ - unsigned int counter; - if (cpu < 0) - cpu = smp_processor_id(); - - counter = nmi_evntsel_msr_to_bit(msr); - BUG_ON(counter > NMI_MAX_COUNTER_BITS); - - clear_bit(counter, &per_cpu(evntsel_nmi_owner, cpu)[0]); -} - -int reserve_evntsel_nmi(unsigned int msr) -{ - int cpu, i; - for_each_possible_cpu (cpu) { - if (!__reserve_evntsel_nmi(cpu, msr)) { - for_each_possible_cpu (i) { - if (i >= cpu) - break; - __release_evntsel_nmi(i, msr); - } - return 0; - } - } - return 1; -} - -void release_evntsel_nmi(unsigned int msr) -{ - int cpu; - for_each_possible_cpu (cpu) { - __release_evntsel_nmi(cpu, msr); - } -} - -static __cpuinit inline int nmi_known_cpu(void) -{ - switch (boot_cpu_data.x86_vendor) { - case X86_VENDOR_AMD: - return ((boot_cpu_data.x86 == 15) || (boot_cpu_data.x86 == 6) - || (boot_cpu_data.x86 == 16)); - case X86_VENDOR_INTEL: - if (cpu_has(&boot_cpu_data, X86_FEATURE_ARCH_PERFMON)) - return 1; - else - return ((boot_cpu_data.x86 == 15) || (boot_cpu_data.x86 == 6)); - } - return 0; -} - static int endflag __initdata = 0; #ifdef CONFIG_SMP @@ -281,28 +72,6 @@ static __init void nmi_cpu_busy(void *data) } #endif -static unsigned int adjust_for_32bit_ctr(unsigned int hz) -{ - u64 counter_val; - unsigned int retval = hz; - - /* - * On Intel CPUs with P6/ARCH_PERFMON only 32 bits in the counter - * are writable, with higher bits sign extending from bit 31. - * So, we can only program the counter with 31 bit values and - * 32nd bit should be 1, for 33.. to be 1. - * Find the appropriate nmi_hz - */ - counter_val = (u64)cpu_khz * 1000; - do_div(counter_val, retval); - if (counter_val > 0x7fffffffULL) { - u64 count = (u64)cpu_khz * 1000; - do_div(count, 0x7fffffffUL); - retval = count + 1; - } - return retval; -} - static int __init check_nmi_watchdog(void) { unsigned int *prev_nmi_count; @@ -335,14 +104,14 @@ static int __init check_nmi_watchdog(void) if (!cpu_isset(cpu, cpu_callin_map)) continue; #endif - if (!per_cpu(nmi_watchdog_ctlblk, cpu).enabled) + if (!per_cpu(wd_enabled, cpu)) continue; if (nmi_count(cpu) - prev_nmi_count[cpu] <= 5) { printk("CPU#%d: NMI appears to be stuck (%d->%d)!\n", cpu, prev_nmi_count[cpu], nmi_count(cpu)); - per_cpu(nmi_watchdog_ctlblk, cpu).enabled = 0; + per_cpu(wd_enabled, cpu) = 0; atomic_dec(&nmi_active); } } @@ -356,16 +125,8 @@ static int __init check_nmi_watchdog(void) /* 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) { - struct nmi_watchdog_ctlblk *wd = &__get_cpu_var(nmi_watchdog_ctlblk); - - nmi_hz = 1; - - if (wd->perfctr_msr == MSR_P6_PERFCTR0 || - wd->perfctr_msr == MSR_ARCH_PERFMON_PERFCTR1) { - nmi_hz = adjust_for_32bit_ctr(nmi_hz); - } - } + if (nmi_watchdog == NMI_LOCAL_APIC) + nmi_hz = lapic_adjust_nmi_hz(1); kfree(prev_nmi_count); return 0; @@ -388,85 +149,8 @@ static int __init setup_nmi_watchdog(char *str) __setup("nmi_watchdog=", setup_nmi_watchdog); -static void disable_lapic_nmi_watchdog(void) -{ - BUG_ON(nmi_watchdog != NMI_LOCAL_APIC); - - if (atomic_read(&nmi_active) <= 0) - return; - - on_each_cpu(stop_apic_nmi_watchdog, NULL, 0, 1); - - BUG_ON(atomic_read(&nmi_active) != 0); -} - -static void enable_lapic_nmi_watchdog(void) -{ - BUG_ON(nmi_watchdog != NMI_LOCAL_APIC); - - /* are we already enabled */ - if (atomic_read(&nmi_active) != 0) - return; - - /* are we lapic aware */ - if (nmi_known_cpu() <= 0) - return; - - on_each_cpu(setup_apic_nmi_watchdog, NULL, 0, 1); - touch_nmi_watchdog(); -} - -void disable_timer_nmi_watchdog(void) -{ - BUG_ON(nmi_watchdog != NMI_IO_APIC); - - if (atomic_read(&nmi_active) <= 0) - return; - - disable_irq(0); - on_each_cpu(stop_apic_nmi_watchdog, NULL, 0, 1); - - BUG_ON(atomic_read(&nmi_active) != 0); -} - -void enable_timer_nmi_watchdog(void) -{ - BUG_ON(nmi_watchdog != NMI_IO_APIC); - - if (atomic_read(&nmi_active) == 0) { - touch_nmi_watchdog(); - on_each_cpu(setup_apic_nmi_watchdog, NULL, 0, 1); - enable_irq(0); - } -} - -static void __acpi_nmi_disable(void *__unused) -{ - apic_write_around(APIC_LVT0, APIC_DM_NMI | APIC_LVT_MASKED); -} -/* - * Disable timer based NMIs on all CPUs: - */ -void acpi_nmi_disable(void) -{ - if (atomic_read(&nmi_active) && nmi_watchdog == NMI_IO_APIC) - on_each_cpu(__acpi_nmi_disable, NULL, 0, 1); -} - -static void __acpi_nmi_enable(void *__unused) -{ - apic_write_around(APIC_LVT0, APIC_DM_NMI); -} - -/* - * Enable timer based NMIs on all CPUs: - */ -void acpi_nmi_enable(void) -{ - if (atomic_read(&nmi_active) && nmi_watchdog == NMI_IO_APIC) - on_each_cpu(__acpi_nmi_enable, NULL, 0, 1); -} +/* Suspend/resume support */ #ifdef CONFIG_PM @@ -513,7 +197,7 @@ static int __init init_lapic_nmi_sysfs(void) if (nmi_watchdog != NMI_LOCAL_APIC) return 0; - if ( atomic_read(&nmi_active) < 0 ) + if (atomic_read(&nmi_active) < 0) return 0; error = sysdev_class_register(&nmi_sysclass); @@ -526,433 +210,69 @@ 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 write_watchdog_counter(unsigned int perfctr_msr, const char *descr) -{ - u64 count = (u64)cpu_khz * 1000; - - do_div(count, nmi_hz); - if(descr) - Dprintk("setting %s to -0x%08Lx\n", descr, count); - wrmsrl(perfctr_msr, 0 - count); -} - -static void write_watchdog_counter32(unsigned int perfctr_msr, - const char *descr) -{ - u64 count = (u64)cpu_khz * 1000; - - do_div(count, nmi_hz); - if(descr) - Dprintk("setting %s to -0x%08Lx\n", descr, count); - wrmsr(perfctr_msr, (u32)(-count), 0); -} - -/* 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 - -static int setup_k7_watchdog(void) -{ - unsigned int perfctr_msr, evntsel_msr; - unsigned int evntsel; - struct nmi_watchdog_ctlblk *wd = &__get_cpu_var(nmi_watchdog_ctlblk); - - perfctr_msr = MSR_K7_PERFCTR0; - evntsel_msr = MSR_K7_EVNTSEL0; - if (!__reserve_perfctr_nmi(-1, perfctr_msr)) - goto fail; - - if (!__reserve_evntsel_nmi(-1, evntsel_msr)) - goto fail1; - - wrmsrl(perfctr_msr, 0UL); - - evntsel = K7_EVNTSEL_INT - | K7_EVNTSEL_OS - | K7_EVNTSEL_USR - | K7_NMI_EVENT; - - /* setup the timer */ - wrmsr(evntsel_msr, evntsel, 0); - write_watchdog_counter(perfctr_msr, "K7_PERFCTR0"); - apic_write(APIC_LVTPC, APIC_DM_NMI); - evntsel |= K7_EVNTSEL_ENABLE; - wrmsr(evntsel_msr, evntsel, 0); - - wd->perfctr_msr = perfctr_msr; - wd->evntsel_msr = evntsel_msr; - wd->cccr_msr = 0; //unused - wd->check_bit = 1ULL<<63; - return 1; -fail1: - __release_perfctr_nmi(-1, perfctr_msr); -fail: - return 0; -} - -static void stop_k7_watchdog(void) -{ - struct nmi_watchdog_ctlblk *wd = &__get_cpu_var(nmi_watchdog_ctlblk); - - wrmsr(wd->evntsel_msr, 0, 0); - - __release_evntsel_nmi(-1, wd->evntsel_msr); - __release_perfctr_nmi(-1, wd->perfctr_msr); -} - -#define P6_EVNTSEL0_ENABLE (1 << 22) -#define P6_EVNTSEL_INT (1 << 20) -#define P6_EVNTSEL_OS (1 << 17) -#define P6_EVNTSEL_USR (1 << 16) -#define P6_EVENT_CPU_CLOCKS_NOT_HALTED 0x79 -#define P6_NMI_EVENT P6_EVENT_CPU_CLOCKS_NOT_HALTED - -static int setup_p6_watchdog(void) -{ - unsigned int perfctr_msr, evntsel_msr; - unsigned int evntsel; - struct nmi_watchdog_ctlblk *wd = &__get_cpu_var(nmi_watchdog_ctlblk); - - perfctr_msr = MSR_P6_PERFCTR0; - evntsel_msr = MSR_P6_EVNTSEL0; - if (!__reserve_perfctr_nmi(-1, perfctr_msr)) - goto fail; - - if (!__reserve_evntsel_nmi(-1, evntsel_msr)) - goto fail1; - - wrmsrl(perfctr_msr, 0UL); - - evntsel = P6_EVNTSEL_INT - | P6_EVNTSEL_OS - | P6_EVNTSEL_USR - | P6_NMI_EVENT; - - /* setup the timer */ - wrmsr(evntsel_msr, evntsel, 0); - nmi_hz = adjust_for_32bit_ctr(nmi_hz); - write_watchdog_counter32(perfctr_msr, "P6_PERFCTR0"); - apic_write(APIC_LVTPC, APIC_DM_NMI); - evntsel |= P6_EVNTSEL0_ENABLE; - wrmsr(evntsel_msr, evntsel, 0); - - wd->perfctr_msr = perfctr_msr; - wd->evntsel_msr = evntsel_msr; - wd->cccr_msr = 0; //unused - wd->check_bit = 1ULL<<39; - return 1; -fail1: - __release_perfctr_nmi(-1, perfctr_msr); -fail: - return 0; -} - -static void stop_p6_watchdog(void) -{ - struct nmi_watchdog_ctlblk *wd = &__get_cpu_var(nmi_watchdog_ctlblk); - - wrmsr(wd->evntsel_msr, 0, 0); - - __release_evntsel_nmi(-1, wd->evntsel_msr); - __release_perfctr_nmi(-1, wd->perfctr_msr); -} - -/* Note that these events don't tick when the CPU idles. This means - the frequency varies with CPU load. */ - -#define MSR_P4_MISC_ENABLE_PERF_AVAIL (1<<7) -#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) -#define P4_CCCR_OVF (1<<31) -/* 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] */ - -static int setup_p4_watchdog(void) +static void __acpi_nmi_enable(void *__unused) { - unsigned int perfctr_msr, evntsel_msr, cccr_msr; - unsigned int evntsel, cccr_val; - unsigned int misc_enable, dummy; - unsigned int ht_num; - struct nmi_watchdog_ctlblk *wd = &__get_cpu_var(nmi_watchdog_ctlblk); - - rdmsr(MSR_IA32_MISC_ENABLE, misc_enable, dummy); - if (!(misc_enable & MSR_P4_MISC_ENABLE_PERF_AVAIL)) - return 0; - -#ifdef CONFIG_SMP - /* detect which hyperthread we are on */ - if (smp_num_siblings == 2) { - unsigned int ebx, apicid; - - ebx = cpuid_ebx(1); - apicid = (ebx >> 24) & 0xff; - ht_num = apicid & 1; - } else -#endif - ht_num = 0; - - /* performance counters are shared resources - * assign each hyperthread its own set - * (re-use the ESCR0 register, seems safe - * and keeps the cccr_val the same) - */ - if (!ht_num) { - /* logical cpu 0 */ - perfctr_msr = MSR_P4_IQ_PERFCTR0; - evntsel_msr = MSR_P4_CRU_ESCR0; - cccr_msr = MSR_P4_IQ_CCCR0; - cccr_val = P4_CCCR_OVF_PMI0 | P4_CCCR_ESCR_SELECT(4); - } else { - /* logical cpu 1 */ - perfctr_msr = MSR_P4_IQ_PERFCTR1; - evntsel_msr = MSR_P4_CRU_ESCR0; - cccr_msr = MSR_P4_IQ_CCCR1; - cccr_val = P4_CCCR_OVF_PMI1 | P4_CCCR_ESCR_SELECT(4); - } - - if (!__reserve_perfctr_nmi(-1, perfctr_msr)) - goto fail; - - if (!__reserve_evntsel_nmi(-1, evntsel_msr)) - goto fail1; - - evntsel = P4_ESCR_EVENT_SELECT(0x3F) - | P4_ESCR_OS - | P4_ESCR_USR; - - cccr_val |= P4_CCCR_THRESHOLD(15) - | P4_CCCR_COMPLEMENT - | P4_CCCR_COMPARE - | P4_CCCR_REQUIRED; - - wrmsr(evntsel_msr, evntsel, 0); - wrmsr(cccr_msr, cccr_val, 0); - write_watchdog_counter(perfctr_msr, "P4_IQ_COUNTER0"); - apic_write(APIC_LVTPC, APIC_DM_NMI); - cccr_val |= P4_CCCR_ENABLE; - wrmsr(cccr_msr, cccr_val, 0); - wd->perfctr_msr = perfctr_msr; - wd->evntsel_msr = evntsel_msr; - wd->cccr_msr = cccr_msr; - wd->check_bit = 1ULL<<39; - return 1; -fail1: - __release_perfctr_nmi(-1, perfctr_msr); -fail: - return 0; + apic_write_around(APIC_LVT0, APIC_DM_NMI); } -static void stop_p4_watchdog(void) +/* + * Enable timer based NMIs on all CPUs: + */ +void acpi_nmi_enable(void) { - struct nmi_watchdog_ctlblk *wd = &__get_cpu_var(nmi_watchdog_ctlblk); - - wrmsr(wd->cccr_msr, 0, 0); - wrmsr(wd->evntsel_msr, 0, 0); - - __release_evntsel_nmi(-1, wd->evntsel_msr); - __release_perfctr_nmi(-1, wd->perfctr_msr); + if (atomic_read(&nmi_active) && nmi_watchdog == NMI_IO_APIC) + on_each_cpu(__acpi_nmi_enable, NULL, 0, 1); } -#define ARCH_PERFMON_NMI_EVENT_SEL ARCH_PERFMON_UNHALTED_CORE_CYCLES_SEL -#define ARCH_PERFMON_NMI_EVENT_UMASK ARCH_PERFMON_UNHALTED_CORE_CYCLES_UMASK - -static int setup_intel_arch_watchdog(void) +static void __acpi_nmi_disable(void *__unused) { - unsigned int ebx; - union cpuid10_eax eax; - unsigned int unused; - unsigned int perfctr_msr, evntsel_msr; - unsigned int evntsel; - struct nmi_watchdog_ctlblk *wd = &__get_cpu_var(nmi_watchdog_ctlblk); - - /* - * Check whether the Architectural PerfMon supports - * Unhalted Core Cycles Event or not. - * NOTE: Corresponding bit = 0 in ebx indicates event present. - */ - cpuid(10, &(eax.full), &ebx, &unused, &unused); - if ((eax.split.mask_length < (ARCH_PERFMON_UNHALTED_CORE_CYCLES_INDEX+1)) || - (ebx & ARCH_PERFMON_UNHALTED_CORE_CYCLES_PRESENT)) - goto fail; - - perfctr_msr = MSR_ARCH_PERFMON_PERFCTR1; - evntsel_msr = MSR_ARCH_PERFMON_EVENTSEL1; - - if (!__reserve_perfctr_nmi(-1, perfctr_msr)) - goto fail; - - if (!__reserve_evntsel_nmi(-1, evntsel_msr)) - goto fail1; - - wrmsrl(perfctr_msr, 0UL); - - evntsel = ARCH_PERFMON_EVENTSEL_INT - | ARCH_PERFMON_EVENTSEL_OS - | ARCH_PERFMON_EVENTSEL_USR - | ARCH_PERFMON_NMI_EVENT_SEL - | ARCH_PERFMON_NMI_EVENT_UMASK; - - /* setup the timer */ - wrmsr(evntsel_msr, evntsel, 0); - nmi_hz = adjust_for_32bit_ctr(nmi_hz); - write_watchdog_counter32(perfctr_msr, "INTEL_ARCH_PERFCTR0"); - apic_write(APIC_LVTPC, APIC_DM_NMI); - evntsel |= ARCH_PERFMON_EVENTSEL0_ENABLE; - wrmsr(evntsel_msr, evntsel, 0); - - wd->perfctr_msr = perfctr_msr; - wd->evntsel_msr = evntsel_msr; - wd->cccr_msr = 0; //unused - wd->check_bit = 1ULL << (eax.split.bit_width - 1); - return 1; -fail1: - __release_perfctr_nmi(-1, perfctr_msr); -fail: - return 0; + apic_write(APIC_LVT0, APIC_DM_NMI | APIC_LVT_MASKED); } -static void stop_intel_arch_watchdog(void) +/* + * Disable timer based NMIs on all CPUs: + */ +void acpi_nmi_disable(void) { - unsigned int ebx; - union cpuid10_eax eax; - unsigned int unused; - struct nmi_watchdog_ctlblk *wd = &__get_cpu_var(nmi_watchdog_ctlblk); - - /* - * Check whether the Architectural PerfMon supports - * Unhalted Core Cycles Event or not. - * NOTE: Corresponding bit = 0 in ebx indicates event present. - */ - cpuid(10, &(eax.full), &ebx, &unused, &unused); - if ((eax.split.mask_length < (ARCH_PERFMON_UNHALTED_CORE_CYCLES_INDEX+1)) || - (ebx & ARCH_PERFMON_UNHALTED_CORE_CYCLES_PRESENT)) - return; - - wrmsr(wd->evntsel_msr, 0, 0); - __release_evntsel_nmi(-1, wd->evntsel_msr); - __release_perfctr_nmi(-1, wd->perfctr_msr); + if (atomic_read(&nmi_active) && nmi_watchdog == NMI_IO_APIC) + on_each_cpu(__acpi_nmi_disable, NULL, 0, 1); } void setup_apic_nmi_watchdog (void *unused) { - struct nmi_watchdog_ctlblk *wd = &__get_cpu_var(nmi_watchdog_ctlblk); - - /* only support LOCAL and IO APICs for now */ - if ((nmi_watchdog != NMI_LOCAL_APIC) && - (nmi_watchdog != NMI_IO_APIC)) - return; - - if (wd->enabled == 1) - return; + if (__get_cpu_var(wd_enabled)) + return; /* 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)) return; - if (nmi_watchdog == NMI_LOCAL_APIC) { - switch (boot_cpu_data.x86_vendor) { - case X86_VENDOR_AMD: - if (boot_cpu_data.x86 != 6 && boot_cpu_data.x86 != 15 && - boot_cpu_data.x86 != 16) - return; - if (!setup_k7_watchdog()) - return; - break; - case X86_VENDOR_INTEL: - if (cpu_has(&boot_cpu_data, X86_FEATURE_ARCH_PERFMON)) { - if (!setup_intel_arch_watchdog()) - return; - break; - } - switch (boot_cpu_data.x86) { - case 6: - if (boot_cpu_data.x86_model > 0xd) - return; - - if (!setup_p6_watchdog()) - return; - break; - case 15: - if (boot_cpu_data.x86_model > 0x4) - return; - - if (!setup_p4_watchdog()) - return; - break; - default: - return; - } - break; - default: + switch (nmi_watchdog) { + case NMI_LOCAL_APIC: + __get_cpu_var(wd_enabled) = 1; /* enable it before to avoid race with handler */ + if (lapic_watchdog_init(nmi_hz) < 0) { + __get_cpu_var(wd_enabled) = 0; return; } + /* FALL THROUGH */ + case NMI_IO_APIC: + __get_cpu_var(wd_enabled) = 1; + atomic_inc(&nmi_active); } - wd->enabled = 1; - atomic_inc(&nmi_active); } void stop_apic_nmi_watchdog(void *unused) { - struct nmi_watchdog_ctlblk *wd = &__get_cpu_var(nmi_watchdog_ctlblk); - /* only support LOCAL and IO APICs for now */ if ((nmi_watchdog != NMI_LOCAL_APIC) && (nmi_watchdog != NMI_IO_APIC)) return; - - if (wd->enabled == 0) + if (__get_cpu_var(wd_enabled) == 0) return; - - if (nmi_watchdog == NMI_LOCAL_APIC) { - switch (boot_cpu_data.x86_vendor) { - case X86_VENDOR_AMD: - stop_k7_watchdog(); - break; - case X86_VENDOR_INTEL: - if (cpu_has(&boot_cpu_data, X86_FEATURE_ARCH_PERFMON)) { - stop_intel_arch_watchdog(); - break; - } - switch (boot_cpu_data.x86) { - case 6: - if (boot_cpu_data.x86_model > 0xd) - break; - stop_p6_watchdog(); - break; - case 15: - if (boot_cpu_data.x86_model > 0x4) - break; - stop_p4_watchdog(); - break; - } - break; - default: - return; - } - } - wd->enabled = 0; + if (nmi_watchdog == NMI_LOCAL_APIC) + lapic_watchdog_stop(); + __get_cpu_var(wd_enabled) = 0; atomic_dec(&nmi_active); } @@ -1008,8 +328,6 @@ __kprobes int nmi_watchdog_tick(struct pt_regs * regs, unsigned reason) unsigned int sum; int touched = 0; int cpu = smp_processor_id(); - struct nmi_watchdog_ctlblk *wd = &__get_cpu_var(nmi_watchdog_ctlblk); - u64 dummy; int rc=0; /* check for other users first */ @@ -1052,53 +370,20 @@ __kprobes int nmi_watchdog_tick(struct pt_regs * regs, unsigned reason) alert_counter[cpu] = 0; } /* see if the nmi watchdog went off */ - if (wd->enabled) { - if (nmi_watchdog == NMI_LOCAL_APIC) { - rdmsrl(wd->perfctr_msr, dummy); - if (dummy & wd->check_bit){ - /* this wasn't a watchdog timer interrupt */ - goto done; - } - - /* only Intel P4 uses the cccr msr */ - if (wd->cccr_msr != 0) { - /* - * 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. - */ - rdmsrl(wd->cccr_msr, dummy); - dummy &= ~P4_CCCR_OVF; - wrmsrl(wd->cccr_msr, dummy); - apic_write(APIC_LVTPC, APIC_DM_NMI); - /* start the cycle over again */ - write_watchdog_counter(wd->perfctr_msr, NULL); - } - else if (wd->perfctr_msr == MSR_P6_PERFCTR0 || - wd->perfctr_msr == MSR_ARCH_PERFMON_PERFCTR1) { - /* P6 based Pentium M need to re-unmask - * the apic vector but it doesn't hurt - * other P6 variant. - * ArchPerfom/Core Duo also needs this */ - apic_write(APIC_LVTPC, APIC_DM_NMI); - /* P6/ARCH_PERFMON has 32 bit counter write */ - write_watchdog_counter32(wd->perfctr_msr, NULL); - } else { - /* start the cycle over again */ - write_watchdog_counter(wd->perfctr_msr, NULL); - } - rc = 1; - } else if (nmi_watchdog == NMI_IO_APIC) { - /* don't know how to accurately check for this. - * just assume it was a watchdog timer interrupt - * This matches the old behaviour. - */ - rc = 1; - } + if (!__get_cpu_var(wd_enabled)) + return rc; + switch (nmi_watchdog) { + case NMI_LOCAL_APIC: + rc |= lapic_wd_event(nmi_hz); + break; + case NMI_IO_APIC: + /* don't know how to accurately check for this. + * just assume it was a watchdog timer interrupt + * This matches the old behaviour. + */ + rc = 1; + break; } -done: return rc; } @@ -1143,7 +428,7 @@ int proc_nmi_enabled(struct ctl_table *table, int write, struct file *file, } if (nmi_watchdog == NMI_DEFAULT) { - if (nmi_known_cpu() > 0) + if (lapic_watchdog_ok()) nmi_watchdog = NMI_LOCAL_APIC; else nmi_watchdog = NMI_IO_APIC; @@ -1179,11 +464,3 @@ void __trigger_all_cpu_backtrace(void) EXPORT_SYMBOL(nmi_active); EXPORT_SYMBOL(nmi_watchdog); -EXPORT_SYMBOL(avail_to_resrv_perfctr_nmi); -EXPORT_SYMBOL(avail_to_resrv_perfctr_nmi_bit); -EXPORT_SYMBOL(reserve_perfctr_nmi); -EXPORT_SYMBOL(release_perfctr_nmi); -EXPORT_SYMBOL(reserve_evntsel_nmi); -EXPORT_SYMBOL(release_evntsel_nmi); -EXPORT_SYMBOL(disable_timer_nmi_watchdog); -EXPORT_SYMBOL(enable_timer_nmi_watchdog); |