diff options
Diffstat (limited to 'arch/i386/kernel/nmi.c')
| -rw-r--r-- | arch/i386/kernel/nmi.c | 65 |
1 files changed, 64 insertions, 1 deletions
diff --git a/arch/i386/kernel/nmi.c b/arch/i386/kernel/nmi.c index bd3875419630..a76e93146585 100644 --- a/arch/i386/kernel/nmi.c +++ b/arch/i386/kernel/nmi.c @@ -24,6 +24,7 @@ #include <asm/smp.h> #include <asm/nmi.h> +#include <asm/intel_arch_perfmon.h> #include "mach_traps.h" @@ -95,6 +96,9 @@ int nmi_active; (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) +#define ARCH_PERFMON_NMI_EVENT_SEL ARCH_PERFMON_UNHALTED_CORE_CYCLES_SEL +#define ARCH_PERFMON_NMI_EVENT_UMASK ARCH_PERFMON_UNHALTED_CORE_CYCLES_UMASK + #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 @@ -207,6 +211,8 @@ static int __init setup_nmi_watchdog(char *str) __setup("nmi_watchdog=", setup_nmi_watchdog); +static void disable_intel_arch_watchdog(void); + static void disable_lapic_nmi_watchdog(void) { if (nmi_active <= 0) @@ -216,6 +222,10 @@ static void disable_lapic_nmi_watchdog(void) wrmsr(MSR_K7_EVNTSEL0, 0, 0); break; case X86_VENDOR_INTEL: + if (cpu_has(&boot_cpu_data, X86_FEATURE_ARCH_PERFMON)) { + disable_intel_arch_watchdog(); + break; + } switch (boot_cpu_data.x86) { case 6: if (boot_cpu_data.x86_model > 0xd) @@ -444,6 +454,53 @@ static int setup_p4_watchdog(void) return 1; } +static void disable_intel_arch_watchdog(void) +{ + unsigned ebx; + + /* + * Check whether the Architectural PerfMon supports + * Unhalted Core Cycles Event or not. + * NOTE: Corresponding bit = 0 in ebp indicates event present. + */ + ebx = cpuid_ebx(10); + if (!(ebx & ARCH_PERFMON_UNHALTED_CORE_CYCLES_PRESENT)) + wrmsr(MSR_ARCH_PERFMON_EVENTSEL0, 0, 0); +} + +static int setup_intel_arch_watchdog(void) +{ + unsigned int evntsel; + unsigned ebx; + + /* + * Check whether the Architectural PerfMon supports + * Unhalted Core Cycles Event or not. + * NOTE: Corresponding bit = 0 in ebp indicates event present. + */ + ebx = cpuid_ebx(10); + if ((ebx & ARCH_PERFMON_UNHALTED_CORE_CYCLES_PRESENT)) + return 0; + + nmi_perfctr_msr = MSR_ARCH_PERFMON_PERFCTR0; + + clear_msr_range(MSR_ARCH_PERFMON_EVENTSEL0, 2); + clear_msr_range(MSR_ARCH_PERFMON_PERFCTR0, 2); + + evntsel = ARCH_PERFMON_EVENTSEL_INT + | ARCH_PERFMON_EVENTSEL_OS + | ARCH_PERFMON_EVENTSEL_USR + | ARCH_PERFMON_NMI_EVENT_SEL + | ARCH_PERFMON_NMI_EVENT_UMASK; + + wrmsr(MSR_ARCH_PERFMON_EVENTSEL0, evntsel, 0); + write_watchdog_counter("INTEL_ARCH_PERFCTR0"); + apic_write(APIC_LVTPC, APIC_DM_NMI); + evntsel |= ARCH_PERFMON_EVENTSEL0_ENABLE; + wrmsr(MSR_ARCH_PERFMON_EVENTSEL0, evntsel, 0); + return 1; +} + void setup_apic_nmi_watchdog (void) { switch (boot_cpu_data.x86_vendor) { @@ -453,6 +510,11 @@ void setup_apic_nmi_watchdog (void) setup_k7_watchdog(); 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) @@ -556,7 +618,8 @@ void nmi_watchdog_tick (struct pt_regs * regs) wrmsr(MSR_P4_IQ_CCCR0, nmi_p4_cccr_val, 0); apic_write(APIC_LVTPC, APIC_DM_NMI); } - else if (nmi_perfctr_msr == MSR_P6_PERFCTR0) { + else if (nmi_perfctr_msr == MSR_P6_PERFCTR0 || + nmi_perfctr_msr == MSR_ARCH_PERFMON_PERFCTR0) { /* Only P6 based Pentium M need to re-unmask * the apic vector but it doesn't hurt * other P6 variant */ |