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Diffstat (limited to 'arch/x86_64/kernel/nmi.c')
-rw-r--r--arch/x86_64/kernel/nmi.c89
1 files changed, 76 insertions, 13 deletions
diff --git a/arch/x86_64/kernel/nmi.c b/arch/x86_64/kernel/nmi.c
index 4e6357fe0ec3..399489c93132 100644
--- a/arch/x86_64/kernel/nmi.c
+++ b/arch/x86_64/kernel/nmi.c
@@ -15,11 +15,7 @@
#include <linux/config.h>
#include <linux/mm.h>
#include <linux/delay.h>
-#include <linux/bootmem.h>
-#include <linux/smp_lock.h>
#include <linux/interrupt.h>
-#include <linux/mc146818rtc.h>
-#include <linux/kernel_stat.h>
#include <linux/module.h>
#include <linux/sysdev.h>
#include <linux/nmi.h>
@@ -27,14 +23,11 @@
#include <linux/kprobes.h>
#include <asm/smp.h>
-#include <asm/mtrr.h>
-#include <asm/mpspec.h>
#include <asm/nmi.h>
-#include <asm/msr.h>
#include <asm/proto.h>
#include <asm/kdebug.h>
-#include <asm/local.h>
#include <asm/mce.h>
+#include <asm/intel_arch_perfmon.h>
/*
* lapic_nmi_owner tracks the ownership of the lapic NMI hardware:
@@ -74,6 +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)
@@ -105,7 +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;
}
@@ -211,6 +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)
@@ -223,6 +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;
}
@@ -375,6 +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)
{
@@ -428,10 +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:
@@ -516,7 +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));
}
}