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-rw-r--r--arch/i386/kernel/cpu/intel.c6
-rw-r--r--arch/i386/kernel/nmi.c65
2 files changed, 70 insertions, 1 deletions
diff --git a/arch/i386/kernel/cpu/intel.c b/arch/i386/kernel/cpu/intel.c
index 5386b29bb5a..10afc645c54 100644
--- a/arch/i386/kernel/cpu/intel.c
+++ b/arch/i386/kernel/cpu/intel.c
@@ -122,6 +122,12 @@ static void __cpuinit init_intel(struct cpuinfo_x86 *c)
select_idle_routine(c);
l2 = 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);
+ }
/* SEP CPUID bug: Pentium Pro reports SEP but doesn't have it until model 3 mask 3 */
if ((c->x86<<8 | c->x86_model<<4 | c->x86_mask) < 0x633)
diff --git a/arch/i386/kernel/nmi.c b/arch/i386/kernel/nmi.c
index bd387541963..a76e9314658 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 */