#include <asm/apic.h>
#include <asm/perf_event.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 const 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.
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)
{
clear_bit(counter, evntsel_nmi_owner);
}
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(stop_apic_nmi_watchdog, NULL, 1);
-
- if (wd_ops)
- 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, 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)
- pr_debug("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)
- pr_debug("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 = wd_ops->perfctr;
- evntsel_msr = wd_ops->evntsel;
-
- 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);
-
- /* initialize the wd struct before enabling */
- wd->perfctr_msr = perfctr_msr;
- wd->evntsel_msr = evntsel_msr;
- wd->cccr_msr = 0; /* unused */
-
- /* ok, everything is initialized, announce that we're set */
- cpu_nmi_set_wd_enabled();
-
- apic_write(APIC_LVTPC, APIC_DM_NMI);
- evntsel |= K7_EVNTSEL_ENABLE;
- wrmsr(evntsel_msr, evntsel, 0);
-
- return 1;
-}
-
-static void single_msr_stop_watchdog(void)
-{
- 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->evntsel);
- release_perfctr_nmi(wd_ops->perfctr);
-}
-
-static void __kprobes
-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 const 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 << 47,
-};
-
-/*
- * 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 = wd_ops->perfctr;
- evntsel_msr = wd_ops->evntsel;
-
- /* KVM doesn't implement this MSR */
- if (wrmsr_safe(perfctr_msr, 0, 0) < 0)
- return 0;
-
- 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);
-
- /* initialize the wd struct before enabling */
- wd->perfctr_msr = perfctr_msr;
- wd->evntsel_msr = evntsel_msr;
- wd->cccr_msr = 0; /* unused */
-
- /* ok, everything is initialized, announce that we're set */
- cpu_nmi_set_wd_enabled();
-
- apic_write(APIC_LVTPC, APIC_DM_NMI);
- evntsel |= P6_EVNTSEL0_ENABLE;
- wrmsr(evntsel_msr, evntsel, 0);
-
- return 1;
-}
-
-static void __kprobes 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 const 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)
-
-#define P4_CONTROLS 18
-static unsigned int p4_controls[18] = {
- MSR_P4_BPU_CCCR0,
- MSR_P4_BPU_CCCR1,
- MSR_P4_BPU_CCCR2,
- MSR_P4_BPU_CCCR3,
- MSR_P4_MS_CCCR0,
- MSR_P4_MS_CCCR1,
- MSR_P4_MS_CCCR2,
- MSR_P4_MS_CCCR3,
- MSR_P4_FLAME_CCCR0,
- MSR_P4_FLAME_CCCR1,
- MSR_P4_FLAME_CCCR2,
- MSR_P4_FLAME_CCCR3,
- MSR_P4_IQ_CCCR0,
- MSR_P4_IQ_CCCR1,
- MSR_P4_IQ_CCCR2,
- MSR_P4_IQ_CCCR3,
- MSR_P4_IQ_CCCR4,
- MSR_P4_IQ_CCCR5,
-};
-/*
- * 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);
-
- /*
- * If we're on the kdump kernel or other situation, we may
- * still have other performance counter registers set to
- * interrupt and they'll keep interrupting forever because
- * of the P4_CCCR_OVF quirk. So we need to ACK all the
- * pending interrupts and disable all the registers here,
- * before reenabling the NMI delivery. Refer to p4_rearm()
- * about the P4_CCCR_OVF quirk.
- */
- if (reset_devices) {
- unsigned int low, high;
- int i;
-
- for (i = 0; i < P4_CONTROLS; i++) {
- rdmsr(p4_controls[i], low, high);
- low &= ~(P4_CCCR_ENABLE | P4_CCCR_OVF);
- wrmsr(p4_controls[i], low, high);
- }
- }
- } else {
- /* logical cpu 1 */
- perfctr_msr = MSR_P4_IQ_PERFCTR1;
- evntsel_msr = MSR_P4_CRU_ESCR0;
- cccr_msr = MSR_P4_IQ_CCCR1;
-
- /* Pentium 4 D processors don't support P4_CCCR_OVF_PMI1 */
- if (boot_cpu_data.x86_model == 4 && boot_cpu_data.x86_mask == 4)
- cccr_val = P4_CCCR_OVF_PMI0;
- else
- cccr_val = P4_CCCR_OVF_PMI1;
- cccr_val |= 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);
-
- wd->perfctr_msr = perfctr_msr;
- wd->evntsel_msr = evntsel_msr;
- wd->cccr_msr = cccr_msr;
-
- /* ok, everything is initialized, announce that we're set */
- cpu_nmi_set_wd_enabled();
-
- apic_write(APIC_LVTPC, APIC_DM_NMI);
- cccr_val |= P4_CCCR_ENABLE;
- wrmsr(cccr_msr, cccr_val, 0);
- return 1;
-}
-
-static void stop_p4_watchdog(void)
-{
- 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_perfctr_nmi(MSR_P4_IQ_PERFCTR1);
-#endif
- release_evntsel_nmi(MSR_P4_CRU_ESCR0);
- release_perfctr_nmi(MSR_P4_IQ_PERFCTR0);
-}
-
-static void __kprobes 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 const 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 struct wd_ops intel_arch_wd_ops;
-
-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 = wd_ops->perfctr;
- evntsel_msr = wd_ops->evntsel;
-
- 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);
-
- wd->perfctr_msr = perfctr_msr;
- wd->evntsel_msr = evntsel_msr;
- wd->cccr_msr = 0; /* unused */
-
- /* ok, everything is initialized, announce that we're set */
- cpu_nmi_set_wd_enabled();
-
- apic_write(APIC_LVTPC, APIC_DM_NMI);
- evntsel |= ARCH_PERFMON_EVENTSEL_ENABLE;
- wrmsr(evntsel_msr, evntsel, 0);
- intel_arch_wd_ops.checkbit = 1ULL << (eax.split.bit_width - 1);
- return 1;
-}
-
-static struct wd_ops intel_arch_wd_ops __read_mostly = {
- .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_PERFCTR1,
- .evntsel = MSR_ARCH_PERFMON_EVENTSEL1,
-};
-
-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 >= 0xf && boot_cpu_data.x86 <= 0x15))
- wd_ops = &k7_wd_ops;
- return;
- case X86_VENDOR_INTEL:
- /* Work around where perfctr1 doesn't have a working enable
- * bit as described in the following errata:
- * AE49 Core Duo and Intel Core Solo 65 nm
- * AN49 Intel Pentium Dual-Core
- * AF49 Dual-Core Intel Xeon Processor LV
- */
- if ((boot_cpu_data.x86 == 6 && boot_cpu_data.x86_model == 14) ||
- ((boot_cpu_data.x86 == 6 && boot_cpu_data.x86_model == 15 &&
- boot_cpu_data.x86_mask == 4))) {
- intel_arch_wd_ops.perfctr = MSR_ARCH_PERFMON_PERFCTR0;
- intel_arch_wd_ops.evntsel = MSR_ARCH_PERFMON_EVENTSEL0;
- }
- 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 > 13)
- return;
-
- wd_ops = &p6_wd_ops;
- break;
- case 15:
- 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) {
- printk(KERN_INFO "NMI watchdog: CPU not supported\n");
- return -1;
- }
-
- if (!wd_ops->reserve()) {
- printk(KERN_ERR
- "NMI watchdog: cannot reserve perfctrs\n");
- 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();
-}
-
-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 __kprobes 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;
-}