diff options
Diffstat (limited to 'arch/i386/kernel/nmi.c')
| -rw-r--r-- | arch/i386/kernel/nmi.c | 107 |
1 files changed, 87 insertions, 20 deletions
diff --git a/arch/i386/kernel/nmi.c b/arch/i386/kernel/nmi.c index 1a6f8bb8881..821df34d2b3 100644 --- a/arch/i386/kernel/nmi.c +++ b/arch/i386/kernel/nmi.c @@ -23,6 +23,7 @@ #include <linux/dmi.h> #include <linux/kprobes.h> #include <linux/cpumask.h> +#include <linux/kernel_stat.h> #include <asm/smp.h> #include <asm/nmi.h> @@ -185,7 +186,8 @@ 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)); + 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; @@ -216,6 +218,28 @@ 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; @@ -281,18 +305,10 @@ static int __init check_nmi_watchdog(void) struct nmi_watchdog_ctlblk *wd = &__get_cpu_var(nmi_watchdog_ctlblk); nmi_hz = 1; - /* - * On Intel CPUs with 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 - */ - if (wd->perfctr_msr == MSR_ARCH_PERFMON_PERFCTR0 && - ((u64)cpu_khz * 1000) > 0x7fffffffULL) { - u64 count = (u64)cpu_khz * 1000; - do_div(count, 0x7fffffffUL); - nmi_hz = count + 1; + + if (wd->perfctr_msr == MSR_P6_PERFCTR0 || + wd->perfctr_msr == MSR_ARCH_PERFMON_PERFCTR0) { + nmi_hz = adjust_for_32bit_ctr(nmi_hz); } } @@ -369,6 +385,34 @@ void enable_timer_nmi_watchdog(void) } } +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); +} + #ifdef CONFIG_PM static int nmi_pm_active; /* nmi_active before suspend */ @@ -442,6 +486,17 @@ static void write_watchdog_counter(unsigned int perfctr_msr, const char *descr) 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. */ @@ -531,7 +586,8 @@ static int setup_p6_watchdog(void) /* setup the timer */ wrmsr(evntsel_msr, evntsel, 0); - write_watchdog_counter(perfctr_msr, "P6_PERFCTR0"); + 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); @@ -704,7 +760,8 @@ static int setup_intel_arch_watchdog(void) /* setup the timer */ wrmsr(evntsel_msr, evntsel, 0); - write_watchdog_counter(perfctr_msr, "INTEL_ARCH_PERFCTR0"); + 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); @@ -762,7 +819,8 @@ void setup_apic_nmi_watchdog (void *unused) 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) + if (boot_cpu_data.x86 != 6 && boot_cpu_data.x86 != 15 && + boot_cpu_data.x86 != 16) return; if (!setup_k7_watchdog()) return; @@ -916,9 +974,13 @@ __kprobes int nmi_watchdog_tick(struct pt_regs * regs, unsigned reason) cpu_clear(cpu, backtrace_mask); } - sum = per_cpu(irq_stat, cpu).apic_timer_irqs; + /* + * 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 + kstat_irqs(0); - /* if the apic timer isn't firing, this cpu isn't doing much */ + /* if the none of the timers isn't firing, this cpu isn't doing much */ if (!touched && last_irq_sums[cpu] == sum) { /* * Ayiee, looks like this CPU is stuck ... @@ -956,6 +1018,8 @@ __kprobes int nmi_watchdog_tick(struct pt_regs * regs, unsigned reason) 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_PERFCTR0) { @@ -964,9 +1028,12 @@ __kprobes int nmi_watchdog_tick(struct pt_regs * regs, unsigned reason) * 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); } - /* 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. |