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-rw-r--r--arch/x86_64/kernel/nmi.c81
-rw-r--r--arch/x86_64/kernel/setup.c7
2 files changed, 83 insertions, 5 deletions
diff --git a/arch/x86_64/kernel/nmi.c b/arch/x86_64/kernel/nmi.c
index ab421e22fa6..399489c9313 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));
}
}
diff --git a/arch/x86_64/kernel/setup.c b/arch/x86_64/kernel/setup.c
index 2a5fce0fd1c..594642a6c03 100644
--- a/arch/x86_64/kernel/setup.c
+++ b/arch/x86_64/kernel/setup.c
@@ -988,6 +988,13 @@ static void __cpuinit init_intel(struct cpuinfo_x86 *c)
unsigned n;
init_intel_cacheinfo(c);
+ if (c->cpuid_level > 9 ) {
+ unsigned eax = cpuid_eax(10);
+ /* Check for version and the number of counters */
+ if ((eax & 0xff) && (((eax>>8) & 0xff) > 1))
+ set_bit(X86_FEATURE_ARCH_PERFMON, &c->x86_capability);
+ }
+
n = c->extended_cpuid_level;
if (n >= 0x80000008) {
unsigned eax = cpuid_eax(0x80000008);