diff options
Diffstat (limited to 'arch/x86_64/kernel/nmi.c')
| -rw-r--r-- | arch/x86_64/kernel/nmi.c | 81 |
1 files changed, 76 insertions, 5 deletions
diff --git a/arch/x86_64/kernel/nmi.c b/arch/x86_64/kernel/nmi.c index ab421e22fa67..399489c93132 100644 --- a/arch/x86_64/kernel/nmi.c +++ b/arch/x86_64/kernel/nmi.c @@ -27,6 +27,7 @@ #include <asm/proto.h> #include <asm/kdebug.h> #include <asm/mce.h> +#include <asm/intel_arch_perfmon.h> /* * lapic_nmi_owner tracks the ownership of the lapic NMI hardware: @@ -66,6 +67,9 @@ static unsigned int nmi_p4_cccr_val; #define K7_EVENT_CYCLES_PROCESSOR_IS_RUNNING 0x76 #define K7_NMI_EVENT K7_EVENT_CYCLES_PROCESSOR_IS_RUNNING +#define ARCH_PERFMON_NMI_EVENT_SEL ARCH_PERFMON_UNHALTED_CORE_CYCLES_SEL +#define ARCH_PERFMON_NMI_EVENT_UMASK ARCH_PERFMON_UNHALTED_CORE_CYCLES_UMASK + #define MSR_P4_MISC_ENABLE 0x1A0 #define MSR_P4_MISC_ENABLE_PERF_AVAIL (1<<7) #define MSR_P4_MISC_ENABLE_PEBS_UNAVAIL (1<<12) @@ -97,7 +101,10 @@ static __cpuinit inline int nmi_known_cpu(void) case X86_VENDOR_AMD: return boot_cpu_data.x86 == 15; case X86_VENDOR_INTEL: - return boot_cpu_data.x86 == 15; + if (cpu_has(&boot_cpu_data, X86_FEATURE_ARCH_PERFMON)) + return 1; + else + return (boot_cpu_data.x86 == 15); } return 0; } @@ -203,6 +210,8 @@ 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) @@ -215,6 +224,8 @@ static void disable_lapic_nmi_watchdog(void) if (boot_cpu_data.x86 == 15) { wrmsr(MSR_P4_IQ_CCCR0, 0, 0); wrmsr(MSR_P4_CRU_ESCR0, 0, 0); + } else if (cpu_has(&boot_cpu_data, X86_FEATURE_ARCH_PERFMON)) { + disable_intel_arch_watchdog(); } break; } @@ -367,6 +378,53 @@ static void setup_k7_watchdog(void) wrmsr(MSR_K7_EVNTSEL0, evntsel, 0); } +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); + wrmsrl(MSR_ARCH_PERFMON_PERFCTR0, -((u64)cpu_khz * 1000 / nmi_hz)); + apic_write(APIC_LVTPC, APIC_DM_NMI); + evntsel |= ARCH_PERFMON_EVENTSEL0_ENABLE; + wrmsr(MSR_ARCH_PERFMON_EVENTSEL0, evntsel, 0); + return 1; +} + static int setup_p4_watchdog(void) { @@ -420,10 +478,16 @@ void setup_apic_nmi_watchdog(void) setup_k7_watchdog(); break; case X86_VENDOR_INTEL: - if (boot_cpu_data.x86 != 15) - return; - if (!setup_p4_watchdog()) + if (cpu_has(&boot_cpu_data, X86_FEATURE_ARCH_PERFMON)) { + if (!setup_intel_arch_watchdog()) + return; + } else if (boot_cpu_data.x86 == 15) { + if (!setup_p4_watchdog()) + return; + } else { return; + } + break; default: @@ -508,7 +572,14 @@ void __kprobes nmi_watchdog_tick(struct pt_regs * regs, unsigned reason) */ wrmsr(MSR_P4_IQ_CCCR0, nmi_p4_cccr_val, 0); apic_write(APIC_LVTPC, APIC_DM_NMI); - } + } else if (nmi_perfctr_msr == MSR_ARCH_PERFMON_PERFCTR0) { + /* + * For Intel based architectural perfmon + * - LVTPC is masked on interrupt and must be + * unmasked by the LVTPC handler. + */ + apic_write(APIC_LVTPC, APIC_DM_NMI); + } wrmsrl(nmi_perfctr_msr, -((u64)cpu_khz * 1000 / nmi_hz)); } } |