Merge branch 'percpu-for-linus' into percpu-for-next

Conflicts:
	arch/sparc/kernel/smp_64.c
	arch/x86/kernel/cpu/perf_counter.c
	arch/x86/kernel/setup_percpu.c
	drivers/cpufreq/cpufreq_ondemand.c
	mm/percpu.c

Conflicts in core and arch percpu codes are mostly from commit
ed78e1e078dd44249f88b1dd8c76dafb39567161 which substituted many
num_possible_cpus() with nr_cpu_ids.  As for-next branch has moved all
the first chunk allocators into mm/percpu.c, the changes are moved
from arch code to mm/percpu.c.

Signed-off-by: Tejun Heo <tj@kernel.org>

8 files changed, 332 insertions, 90 deletions

diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
index 28e5f595604..63fddcd082c 100644
--- a/arch/x86/kernel/cpu/amd.c
+++ b/arch/x86/kernel/cpu/amd.c
@@ -356,7 +356,7 @@ static void __cpuinit early_init_amd(struct cpuinfo_x86 *c)
 #endif
 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_PCI)
 	/* check CPU config space for extended APIC ID */
-	if (c->x86 >= 0xf) {
+	if (cpu_has_apic && c->x86 >= 0xf) {
 		unsigned int val;
 		val = read_pci_config(0, 24, 0, 0x68);
 		if ((val & ((1 << 17) | (1 << 18))) == ((1 << 17) | (1 << 18)))
@@ -400,6 +400,13 @@ static void __cpuinit init_amd(struct cpuinfo_x86 *c)
 		level = cpuid_eax(1);
 		if((level >= 0x0f48 && level < 0x0f50) || level >= 0x0f58)
 			set_cpu_cap(c, X86_FEATURE_REP_GOOD);
+
+		/*
+		 * Some BIOSes incorrectly force this feature, but only K8
+		 * revision D (model = 0x14) and later actually support it.
+		 */
+		if (c->x86_model < 0x14)
+			clear_cpu_cap(c, X86_FEATURE_LAHF_LM);
 	}
 	if (c->x86 == 0x10 || c->x86 == 0x11)
 		set_cpu_cap(c, X86_FEATURE_REP_GOOD);
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index f1961c07af9..5ce60a88027 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -59,7 +59,30 @@ void __init setup_cpu_local_masks(void)
 	alloc_bootmem_cpumask_var(&cpu_sibling_setup_mask);
 }
 
-static const struct cpu_dev *this_cpu __cpuinitdata;
+static void __cpuinit default_init(struct cpuinfo_x86 *c)
+{
+#ifdef CONFIG_X86_64
+	display_cacheinfo(c);
+#else
+	/* Not much we can do here... */
+	/* Check if at least it has cpuid */
+	if (c->cpuid_level == -1) {
+		/* No cpuid. It must be an ancient CPU */
+		if (c->x86 == 4)
+			strcpy(c->x86_model_id, "486");
+		else if (c->x86 == 3)
+			strcpy(c->x86_model_id, "386");
+	}
+#endif
+}
+
+static const struct cpu_dev __cpuinitconst default_cpu = {
+	.c_init		= default_init,
+	.c_vendor	= "Unknown",
+	.c_x86_vendor	= X86_VENDOR_UNKNOWN,
+};
+
+static const struct cpu_dev *this_cpu __cpuinitdata = &default_cpu;
 
 DEFINE_PER_CPU_PAGE_ALIGNED(struct gdt_page, gdt_page) = { .gdt = {
 #ifdef CONFIG_X86_64
@@ -332,29 +355,6 @@ void switch_to_new_gdt(int cpu)
 
 static const struct cpu_dev *__cpuinitdata cpu_devs[X86_VENDOR_NUM] = {};
 
-static void __cpuinit default_init(struct cpuinfo_x86 *c)
-{
-#ifdef CONFIG_X86_64
-	display_cacheinfo(c);
-#else
-	/* Not much we can do here... */
-	/* Check if at least it has cpuid */
-	if (c->cpuid_level == -1) {
-		/* No cpuid. It must be an ancient CPU */
-		if (c->x86 == 4)
-			strcpy(c->x86_model_id, "486");
-		else if (c->x86 == 3)
-			strcpy(c->x86_model_id, "386");
-	}
-#endif
-}
-
-static const struct cpu_dev __cpuinitconst default_cpu = {
-	.c_init	= default_init,
-	.c_vendor = "Unknown",
-	.c_x86_vendor = X86_VENDOR_UNKNOWN,
-};
-
 static void __cpuinit get_model_name(struct cpuinfo_x86 *c)
 {
 	unsigned int *v;
diff --git a/arch/x86/kernel/cpu/cpufreq/powernow-k8.c b/arch/x86/kernel/cpu/cpufreq/powernow-k8.c
index 81cbe64ed6b..2a50ef89100 100644
--- a/arch/x86/kernel/cpu/cpufreq/powernow-k8.c
+++ b/arch/x86/kernel/cpu/cpufreq/powernow-k8.c
@@ -299,7 +299,7 @@ static int transition_pstate(struct powernow_k8_data *data, u32 pstate)
 static int transition_fid_vid(struct powernow_k8_data *data,
 		u32 reqfid, u32 reqvid)
 {
-	if (core_voltage_pre_transition(data, reqvid))
+	if (core_voltage_pre_transition(data, reqvid, reqfid))
 		return 1;
 
 	if (core_frequency_transition(data, reqfid))
@@ -327,17 +327,20 @@ static int transition_fid_vid(struct powernow_k8_data *data,
 
 /* Phase 1 - core voltage transition ... setup voltage */
 static int core_voltage_pre_transition(struct powernow_k8_data *data,
-		u32 reqvid)
+		u32 reqvid, u32 reqfid)
 {
 	u32 rvosteps = data->rvo;
 	u32 savefid = data->currfid;
-	u32 maxvid, lo;
+	u32 maxvid, lo, rvomult = 1;
 
 	dprintk("ph1 (cpu%d): start, currfid 0x%x, currvid 0x%x, "
 		"reqvid 0x%x, rvo 0x%x\n",
 		smp_processor_id(),
 		data->currfid, data->currvid, reqvid, data->rvo);
 
+	if ((savefid < LO_FID_TABLE_TOP) && (reqfid < LO_FID_TABLE_TOP))
+		rvomult = 2;
+	rvosteps *= rvomult;
 	rdmsr(MSR_FIDVID_STATUS, lo, maxvid);
 	maxvid = 0x1f & (maxvid >> 16);
 	dprintk("ph1 maxvid=0x%x\n", maxvid);
@@ -351,7 +354,8 @@ static int core_voltage_pre_transition(struct powernow_k8_data *data,
 			return 1;
 	}
 
-	while ((rvosteps > 0) && ((data->rvo + data->currvid) > reqvid)) {
+	while ((rvosteps > 0) &&
+			((rvomult * data->rvo + data->currvid) > reqvid)) {
 		if (data->currvid == maxvid) {
 			rvosteps = 0;
 		} else {
@@ -384,13 +388,6 @@ static int core_frequency_transition(struct powernow_k8_data *data, u32 reqfid)
 	u32 vcoreqfid, vcocurrfid, vcofiddiff;
 	u32 fid_interval, savevid = data->currvid;
 
-	if ((reqfid < HI_FID_TABLE_BOTTOM) &&
-	    (data->currfid < HI_FID_TABLE_BOTTOM)) {
-		printk(KERN_ERR PFX "ph2: illegal lo-lo transition "
-				"0x%x 0x%x\n", reqfid, data->currfid);
-		return 1;
-	}
-
 	if (data->currfid == reqfid) {
 		printk(KERN_ERR PFX "ph2 null fid transition 0x%x\n",
 				data->currfid);
@@ -407,6 +404,9 @@ static int core_frequency_transition(struct powernow_k8_data *data, u32 reqfid)
 	vcofiddiff = vcocurrfid > vcoreqfid ? vcocurrfid - vcoreqfid
 	    : vcoreqfid - vcocurrfid;
 
+	if ((reqfid <= LO_FID_TABLE_TOP) && (data->currfid <= LO_FID_TABLE_TOP))
+		vcofiddiff = 0;
+
 	while (vcofiddiff > 2) {
 		(data->currfid & 1) ? (fid_interval = 1) : (fid_interval = 2);
 
@@ -1081,14 +1081,6 @@ static int transition_frequency_fidvid(struct powernow_k8_data *data,
 		return 0;
 	}
 
-	if ((fid < HI_FID_TABLE_BOTTOM) &&
-	    (data->currfid < HI_FID_TABLE_BOTTOM)) {
-		printk(KERN_ERR PFX
-		       "ignoring illegal change in lo freq table-%x to 0x%x\n",
-		       data->currfid, fid);
-		return 1;
-	}
-
 	dprintk("cpu %d, changing to fid 0x%x, vid 0x%x\n",
 		smp_processor_id(), fid, vid);
 	freqs.old = find_khz_freq_from_fid(data->currfid);
@@ -1267,7 +1259,7 @@ static int __cpuinit powernowk8_cpu_init(struct cpufreq_policy *pol)
 {
 	static const char ACPI_PSS_BIOS_BUG_MSG[] =
 		KERN_ERR FW_BUG PFX "No compatible ACPI _PSS objects found.\n"
-		KERN_ERR FW_BUG PFX "Try again with latest BIOS.\n";
+		FW_BUG PFX "Try again with latest BIOS.\n";
 	struct powernow_k8_data *data;
 	struct init_on_cpu init_on_cpu;
 	int rc;
diff --git a/arch/x86/kernel/cpu/cpufreq/powernow-k8.h b/arch/x86/kernel/cpu/cpufreq/powernow-k8.h
index c9c1190b5e1..02ce824073c 100644
--- a/arch/x86/kernel/cpu/cpufreq/powernow-k8.h
+++ b/arch/x86/kernel/cpu/cpufreq/powernow-k8.h
@@ -215,7 +215,8 @@ struct pst_s {
 
 #define dprintk(msg...) cpufreq_debug_printk(CPUFREQ_DEBUG_DRIVER, "powernow-k8", msg)
 
-static int core_voltage_pre_transition(struct powernow_k8_data *data, u32 reqvid);
+static int core_voltage_pre_transition(struct powernow_k8_data *data,
+	u32 reqvid, u32 regfid);
 static int core_voltage_post_transition(struct powernow_k8_data *data, u32 reqvid);
 static int core_frequency_transition(struct powernow_k8_data *data, u32 reqfid);
 
diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c
index 20d49835110..14ce5d49b2a 100644
--- a/arch/x86/kernel/cpu/mcheck/mce.c
+++ b/arch/x86/kernel/cpu/mcheck/mce.c
@@ -194,14 +194,14 @@ static void print_mce(struct mce *m)
 		       m->cs, m->ip);
 		if (m->cs == __KERNEL_CS)
 			print_symbol("{%s}", m->ip);
-		printk("\n");
+		printk(KERN_CONT "\n");
 	}
 	printk(KERN_EMERG "TSC %llx ", m->tsc);
 	if (m->addr)
-		printk("ADDR %llx ", m->addr);
+		printk(KERN_CONT "ADDR %llx ", m->addr);
 	if (m->misc)
-		printk("MISC %llx ", m->misc);
-	printk("\n");
+		printk(KERN_CONT "MISC %llx ", m->misc);
+	printk(KERN_CONT "\n");
 	printk(KERN_EMERG "PROCESSOR %u:%x TIME %llu SOCKET %u APIC %x\n",
 			m->cpuvendor, m->cpuid, m->time, m->socketid,
 			m->apicid);
@@ -209,13 +209,13 @@ static void print_mce(struct mce *m)
 
 static void print_mce_head(void)
 {
-	printk(KERN_EMERG "\n" KERN_EMERG "HARDWARE ERROR\n");
+	printk(KERN_EMERG "\nHARDWARE ERROR\n");
 }
 
 static void print_mce_tail(void)
 {
 	printk(KERN_EMERG "This is not a software problem!\n"
-	       KERN_EMERG "Run through mcelog --ascii to decode and contact your hardware vendor\n");
+	       "Run through mcelog --ascii to decode and contact your hardware vendor\n");
 }
 
 #define PANIC_TIMEOUT 5 /* 5 seconds */
@@ -1692,17 +1692,15 @@ static ssize_t set_trigger(struct sys_device *s, struct sysdev_attribute *attr,
 				const char *buf, size_t siz)
 {
 	char *p;
-	int len;
 
 	strncpy(mce_helper, buf, sizeof(mce_helper));
 	mce_helper[sizeof(mce_helper)-1] = 0;
-	len = strlen(mce_helper);
 	p = strchr(mce_helper, '\n');
 
-	if (*p)
+	if (p)
 		*p = 0;
 
-	return len;
+	return strlen(mce_helper) + !!p;
 }
 
 static ssize_t set_ignore_ce(struct sys_device *s,
diff --git a/arch/x86/kernel/cpu/mcheck/therm_throt.c b/arch/x86/kernel/cpu/mcheck/therm_throt.c
index bff8dd191dd..8bc64cfbe93 100644
--- a/arch/x86/kernel/cpu/mcheck/therm_throt.c
+++ b/arch/x86/kernel/cpu/mcheck/therm_throt.c
@@ -36,6 +36,7 @@
 
 static DEFINE_PER_CPU(__u64, next_check) = INITIAL_JIFFIES;
 static DEFINE_PER_CPU(unsigned long, thermal_throttle_count);
+static DEFINE_PER_CPU(bool, thermal_throttle_active);
 
 static atomic_t therm_throt_en		= ATOMIC_INIT(0);
 
@@ -96,24 +97,27 @@ static int therm_throt_process(int curr)
 {
 	unsigned int cpu = smp_processor_id();
 	__u64 tmp_jiffs = get_jiffies_64();
+	bool was_throttled = __get_cpu_var(thermal_throttle_active);
+	bool is_throttled = __get_cpu_var(thermal_throttle_active) = curr;
 
-	if (curr)
+	if (is_throttled)
 		__get_cpu_var(thermal_throttle_count)++;
 
-	if (time_before64(tmp_jiffs, __get_cpu_var(next_check)))
+	if (!(was_throttled ^ is_throttled) &&
+	    time_before64(tmp_jiffs, __get_cpu_var(next_check)))
 		return 0;
 
 	__get_cpu_var(next_check) = tmp_jiffs + CHECK_INTERVAL;
 
 	/* if we just entered the thermal event */
-	if (curr) {
+	if (is_throttled) {
 		printk(KERN_CRIT "CPU%d: Temperature above threshold, "
-		       "cpu clock throttled (total events = %lu)\n", cpu,
-		       __get_cpu_var(thermal_throttle_count));
+		       "cpu clock throttled (total events = %lu)\n",
+		       cpu, __get_cpu_var(thermal_throttle_count));
 
 		add_taint(TAINT_MACHINE_CHECK);
-	} else {
-		printk(KERN_CRIT "CPU%d: Temperature/speed normal\n", cpu);
+	} else if (was_throttled) {
+		printk(KERN_INFO "CPU%d: Temperature/speed normal\n", cpu);
 	}
 
 	return 1;
diff --git a/arch/x86/kernel/cpu/perf_counter.c b/arch/x86/kernel/cpu/perf_counter.c
index 13bd6d6cf0b..3d4ebbd2e12 100644
--- a/arch/x86/kernel/cpu/perf_counter.c
+++ b/arch/x86/kernel/cpu/perf_counter.c
@@ -55,6 +55,7 @@ struct x86_pmu {
 	int		num_counters_fixed;
 	int		counter_bits;
 	u64		counter_mask;
+	int		apic;
 	u64		max_period;
 	u64		intel_ctrl;
 };
@@ -66,6 +67,52 @@ static DEFINE_PER_CPU(struct cpu_hw_counters, cpu_hw_counters) = {
 };
 
 /*
+ * Not sure about some of these
+ */
+static const u64 p6_perfmon_event_map[] =
+{
+  [PERF_COUNT_HW_CPU_CYCLES]		= 0x0079,
+  [PERF_COUNT_HW_INSTRUCTIONS]		= 0x00c0,
+  [PERF_COUNT_HW_CACHE_REFERENCES]	= 0x0f2e,
+  [PERF_COUNT_HW_CACHE_MISSES]		= 0x012e,
+  [PERF_COUNT_HW_BRANCH_INSTRUCTIONS]	= 0x00c4,
+  [PERF_COUNT_HW_BRANCH_MISSES]		= 0x00c5,
+  [PERF_COUNT_HW_BUS_CYCLES]		= 0x0062,
+};
+
+static u64 p6_pmu_event_map(int event)
+{
+	return p6_perfmon_event_map[event];
+}
+
+/*
+ * Counter setting that is specified not to count anything.
+ * We use this to effectively disable a counter.
+ *
+ * L2_RQSTS with 0 MESI unit mask.
+ */
+#define P6_NOP_COUNTER			0x0000002EULL
+
+static u64 p6_pmu_raw_event(u64 event)
+{
+#define P6_EVNTSEL_EVENT_MASK		0x000000FFULL
+#define P6_EVNTSEL_UNIT_MASK		0x0000FF00ULL
+#define P6_EVNTSEL_EDGE_MASK		0x00040000ULL
+#define P6_EVNTSEL_INV_MASK		0x00800000ULL
+#define P6_EVNTSEL_COUNTER_MASK		0xFF000000ULL
+
+#define P6_EVNTSEL_MASK			\
+	(P6_EVNTSEL_EVENT_MASK |	\
+	 P6_EVNTSEL_UNIT_MASK  |	\
+	 P6_EVNTSEL_EDGE_MASK  |	\
+	 P6_EVNTSEL_INV_MASK   |	\
+	 P6_EVNTSEL_COUNTER_MASK)
+
+	return event & P6_EVNTSEL_MASK;
+}
+
+
+/*
  * Intel PerfMon v3. Used on Core2 and later.
  */
 static const u64 intel_perfmon_event_map[] =
@@ -567,6 +614,7 @@ static DEFINE_MUTEX(pmc_reserve_mutex);
 
 static bool reserve_pmc_hardware(void)
 {
+#ifdef CONFIG_X86_LOCAL_APIC
 	int i;
 
 	if (nmi_watchdog == NMI_LOCAL_APIC)
@@ -581,9 +629,11 @@ static bool reserve_pmc_hardware(void)
 		if (!reserve_evntsel_nmi(x86_pmu.eventsel + i))
 			goto eventsel_fail;
 	}
+#endif
 
 	return true;
 
+#ifdef CONFIG_X86_LOCAL_APIC
 eventsel_fail:
 	for (i--; i >= 0; i--)
 		release_evntsel_nmi(x86_pmu.eventsel + i);
@@ -598,10 +648,12 @@ perfctr_fail:
 		enable_lapic_nmi_watchdog();
 
 	return false;
+#endif
 }
 
 static void release_pmc_hardware(void)
 {
+#ifdef CONFIG_X86_LOCAL_APIC
 	int i;
 
 	for (i = 0; i < x86_pmu.num_counters; i++) {
@@ -611,6 +663,7 @@ static void release_pmc_hardware(void)
 
 	if (nmi_watchdog == NMI_LOCAL_APIC)
 		enable_lapic_nmi_watchdog();
+#endif
 }
 
 static void hw_perf_counter_destroy(struct perf_counter *counter)
@@ -666,6 +719,7 @@ static int __hw_perf_counter_init(struct perf_counter *counter)
 {
 	struct perf_counter_attr *attr = &counter->attr;
 	struct hw_perf_counter *hwc = &counter->hw;
+	u64 config;
 	int err;
 
 	if (!x86_pmu_initialized())
@@ -701,6 +755,15 @@ static int __hw_perf_counter_init(struct perf_counter *counter)
 		hwc->sample_period = x86_pmu.max_period;
 		hwc->last_period = hwc->sample_period;
 		atomic64_set(&hwc->period_left, hwc->sample_period);
+	} else {
+		/*
+		 * If we have a PMU initialized but no APIC
+		 * interrupts, we cannot sample hardware
+		 * counters (user-space has to fall back and
+		 * sample via a hrtimer based software counter):
+		 */
+		if (!x86_pmu.apic)
+			return -EOPNOTSUPP;
 	}
 
 	counter->destroy = hw_perf_counter_destroy;
@@ -718,14 +781,40 @@ static int __hw_perf_counter_init(struct perf_counter *counter)
 
 	if (attr->config >= x86_pmu.max_events)
 		return -EINVAL;
+
 	/*
 	 * The generic map:
 	 */
-	hwc->config |= x86_pmu.event_map(attr->config);
+	config = x86_pmu.event_map(attr->config);
+
+	if (config == 0)
+		return -ENOENT;
+
+	if (config == -1LL)
+		return -EINVAL;
+
+	hwc->config |= config;
 
 	return 0;
 }
 
+static void p6_pmu_disable_all(void)
+{
+	struct cpu_hw_counters *cpuc = &__get_cpu_var(cpu_hw_counters);
+	u64 val;
+
+	if (!cpuc->enabled)
+		return;
+
+	cpuc->enabled = 0;
+	barrier();
+
+	/* p6 only has one enable register */
+	rdmsrl(MSR_P6_EVNTSEL0, val);
+	val &= ~ARCH_PERFMON_EVENTSEL0_ENABLE;
+	wrmsrl(MSR_P6_EVNTSEL0, val);
+}
+
 static void intel_pmu_disable_all(void)
 {
 	wrmsrl(MSR_CORE_PERF_GLOBAL_CTRL, 0);
@@ -767,6 +856,23 @@ void hw_perf_disable(void)
 	return x86_pmu.disable_all();
 }
 
+static void p6_pmu_enable_all(void)
+{
+	struct cpu_hw_counters *cpuc = &__get_cpu_var(cpu_hw_counters);
+	unsigned long val;
+
+	if (cpuc->enabled)
+		return;
+
+	cpuc->enabled = 1;
+	barrier();
+
+	/* p6 only has one enable register */
+	rdmsrl(MSR_P6_EVNTSEL0, val);
+	val |= ARCH_PERFMON_EVENTSEL0_ENABLE;
+	wrmsrl(MSR_P6_EVNTSEL0, val);
+}
+
 static void intel_pmu_enable_all(void)
 {
 	wrmsrl(MSR_CORE_PERF_GLOBAL_CTRL, x86_pmu.intel_ctrl);
@@ -784,13 +890,13 @@ static void amd_pmu_enable_all(void)
 	barrier();
 
 	for (idx = 0; idx < x86_pmu.num_counters; idx++) {
+		struct perf_counter *counter = cpuc->counters[idx];
 		u64 val;
 
 		if (!test_bit(idx, cpuc->active_mask))
 			continue;
-		rdmsrl(MSR_K7_EVNTSEL0 + idx, val);
-		if (val & ARCH_PERFMON_EVENTSEL0_ENABLE)
-			continue;
+
+		val = counter->hw.config;
 		val |= ARCH_PERFMON_EVENTSEL0_ENABLE;
 		wrmsrl(MSR_K7_EVNTSEL0 + idx, val);
 	}
@@ -819,16 +925,13 @@ static inline void intel_pmu_ack_status(u64 ack)
 
 static inline void x86_pmu_enable_counter(struct hw_perf_counter *hwc, int idx)
 {
-	int err;
-	err = checking_wrmsrl(hwc->config_base + idx,
+	(void)checking_wrmsrl(hwc->config_base + idx,
 			      hwc->config | ARCH_PERFMON_EVENTSEL0_ENABLE);
 }
 
 static inline void x86_pmu_disable_counter(struct hw_perf_counter *hwc, int idx)
 {
-	int err;
-	err = checking_wrmsrl(hwc->config_base + idx,
-			      hwc->config);
+	(void)checking_wrmsrl(hwc->config_base + idx, hwc->config);
 }
 
 static inline void
@@ -836,13 +939,24 @@ intel_pmu_disable_fixed(struct hw_perf_counter *hwc, int __idx)
 {
 	int idx = __idx - X86_PMC_IDX_FIXED;
 	u64 ctrl_val, mask;
-	int err;
 
 	mask = 0xfULL << (idx * 4);
 
 	rdmsrl(hwc->config_base, ctrl_val);
 	ctrl_val &= ~mask;
-	err = checking_wrmsrl(hwc->config_base, ctrl_val);
+	(void)checking_wrmsrl(hwc->config_base, ctrl_val);
+}
+
+static inline void
+p6_pmu_disable_counter(struct hw_perf_counter *hwc, int idx)
+{
+	struct cpu_hw_counters *cpuc = &__get_cpu_var(cpu_hw_counters);
+	u64 val = P6_NOP_COUNTER;
+
+	if (cpuc->enabled)
+		val |= ARCH_PERFMON_EVENTSEL0_ENABLE;
+
+	(void)checking_wrmsrl(hwc->config_base + idx, val);
 }
 
 static inline void
@@ -943,6 +1057,19 @@ intel_pmu_enable_fixed(struct hw_perf_counter *hwc, int __idx)
 	err = checking_wrmsrl(hwc->config_base, ctrl_val);
 }
 
+static void p6_pmu_enable_counter(struct hw_perf_counter *hwc, int idx)
+{
+	struct cpu_hw_counters *cpuc = &__get_cpu_var(cpu_hw_counters);
+	u64 val;
+
+	val = hwc->config;
+	if (cpuc->enabled)
+		val |= ARCH_PERFMON_EVENTSEL0_ENABLE;
+
+	(void)checking_wrmsrl(hwc->config_base + idx, val);
+}
+
+
 static void intel_pmu_enable_counter(struct hw_perf_counter *hwc, int idx)
 {
 	if (unlikely(hwc->config_base == MSR_ARCH_PERFMON_FIXED_CTR_CTRL)) {
@@ -959,8 +1086,6 @@ static void amd_pmu_enable_counter(struct hw_perf_counter *hwc, int idx)
 
 	if (cpuc->enabled)
 		x86_pmu_enable_counter(hwc, idx);
-	else
-		x86_pmu_disable_counter(hwc, idx);
 }
 
 static int
@@ -1176,6 +1301,49 @@ static void intel_pmu_reset(void)
 	local_irq_restore(flags);
 }
 
+static int p6_pmu_handle_irq(struct pt_regs *regs)
+{
+	struct perf_sample_data data;
+	struct cpu_hw_counters *cpuc;
+	struct perf_counter *counter;
+	struct hw_perf_counter *hwc;
+	int idx, handled = 0;
+	u64 val;
+
+	data.regs = regs;
+	data.addr = 0;
+
+	cpuc = &__get_cpu_var(cpu_hw_counters);
+
+	for (idx = 0; idx < x86_pmu.num_counters; idx++) {
+		if (!test_bit(idx, cpuc->active_mask))
+			continue;
+
+		counter = cpuc->counters[idx];
+		hwc = &counter->hw;
+
+		val = x86_perf_counter_update(counter, hwc, idx);
+		if (val & (1ULL << (x86_pmu.counter_bits - 1)))
+			continue;
+
+		/*
+		 * counter overflow
+		 */
+		handled		= 1;
+		data.period	= counter->hw.last_period;
+
+		if (!x86_perf_counter_set_period(counter, hwc, idx))
+			continue;
+
+		if (perf_counter_overflow(counter, 1, &data))
+			p6_pmu_disable_counter(hwc, idx);
+	}
+
+	if (handled)
+		inc_irq_stat(apic_perf_irqs);
+
+	return handled;
+}
 
 /*
  * This handler is triggered by the local APIC, so the APIC IRQ handling
@@ -1185,14 +1353,13 @@ static int intel_pmu_handle_irq(struct pt_regs *regs)
 {
 	struct perf_sample_data data;
 	struct cpu_hw_counters *cpuc;
-	int bit, cpu, loops;
+	int bit, loops;
 	u64 ack, status;
 
 	data.regs = regs;
 	data.addr = 0;
 
-	cpu = smp_processor_id();
-	cpuc = &per_cpu(cpu_hw_counters, cpu);
+	cpuc = &__get_cpu_var(cpu_hw_counters);
 
 	perf_disable();
 	status = intel_pmu_get_status();
@@ -1249,14 +1416,13 @@ static int amd_pmu_handle_irq(struct pt_regs *regs)
 	struct cpu_hw_counters *cpuc;
 	struct perf_counter *counter;
 	struct hw_perf_counter *hwc;
-	int cpu, idx, handled = 0;
+	int idx, handled = 0;
 	u64 val;
 
 	data.regs = regs;
 	data.addr = 0;
 
-	cpu = smp_processor_id();
-	cpuc = &per_cpu(cpu_hw_counters, cpu);
+	cpuc = &__get_cpu_var(cpu_hw_counters);
 
 	for (idx = 0; idx < x86_pmu.num_counters; idx++) {
 		if (!test_bit(idx, cpuc->active_mask))
@@ -1299,18 +1465,22 @@ void smp_perf_pending_interrupt(struct pt_regs *regs)
 
 void set_perf_counter_pending(void)
 {
+#ifdef CONFIG_X86_LOCAL_APIC
 	apic->send_IPI_self(LOCAL_PENDING_VECTOR);
+#endif
 }
 
 void perf_counters_lapic_init(void)
 {
-	if (!x86_pmu_initialized())
+#ifdef CONFIG_X86_LOCAL_APIC
+	if (!x86_pmu.apic || !x86_pmu_initialized())
 		return;
 
 	/*
 	 * Always use NMI for PMU
 	 */
 	apic_write(APIC_LVTPC, APIC_DM_NMI);
+#endif
 }
 
 static int __kprobes
@@ -1334,7 +1504,9 @@ perf_counter_nmi_handler(struct notifier_block *self,
 
 	regs = args->regs;
 
+#ifdef CONFIG_X86_LOCAL_APIC
 	apic_write(APIC_LVTPC, APIC_DM_NMI);
+#endif
 	/*
 	 * Can't rely on the handled return value to say it was our NMI, two
 	 * counters could trigger 'simultaneously' raising two back-to-back NMIs.
@@ -1353,6 +1525,33 @@ static __read_mostly struct notifier_block perf_counter_nmi_notifier = {
 	.priority		= 1
 };
 
+static struct x86_pmu p6_pmu = {
+	.name			= "p6",
+	.handle_irq		= p6_pmu_handle_irq,
+	.disable_all		= p6_pmu_disable_all,
+	.enable_all		= p6_pmu_enable_all,
+	.enable			= p6_pmu_enable_counter,
+	.disable		= p6_pmu_disable_counter,
+	.eventsel		= MSR_P6_EVNTSEL0,
+	.perfctr		= MSR_P6_PERFCTR0,
+	.event_map		= p6_pmu_event_map,
+	.raw_event		= p6_pmu_raw_event,
+	.max_events		= ARRAY_SIZE(p6_perfmon_event_map),
+	.apic			= 1,
+	.max_period		= (1ULL << 31) - 1,
+	.version		= 0,
+	.num_counters		= 2,
+	/*
+	 * Counters have 40 bits implemented. However they are designed such
+	 * that bits [32-39] are sign extensions of bit 31. As such the
+	 * effective width of a counter for P6-like PMU is 32 bits only.
+	 *
+	 * See IA-32 Intel Architecture Software developer manual Vol 3B
+	 */
+	.counter_bits		= 32,
+	.counter_mask		= (1ULL << 32) - 1,
+};
+
 static struct x86_pmu intel_pmu = {
 	.name			= "Intel",
 	.handle_irq		= intel_pmu_handle_irq,
@@ -1365,6 +1564,7 @@ static struct x86_pmu intel_pmu = {
 	.event_map		= intel_pmu_event_map,
 	.raw_event		= intel_pmu_raw_event,
 	.max_events		= ARRAY_SIZE(intel_perfmon_event_map),
+	.apic			= 1,
 	/*
 	 * Intel PMCs cannot be accessed sanely above 32 bit width,
 	 * so we install an artificial 1<<31 period regardless of
@@ -1388,10 +1588,43 @@ static struct x86_pmu amd_pmu = {
 	.num_counters		= 4,
 	.counter_bits		= 48,
 	.counter_mask		= (1ULL << 48) - 1,
+	.apic			= 1,
 	/* use highest bit to detect overflow */
 	.max_period		= (1ULL << 47) - 1,
 };
 
+static int p6_pmu_init(void)
+{
+	switch (boot_cpu_data.x86_model) {
+	case 1:
+	case 3:  /* Pentium Pro */
+	case 5:
+	case 6:  /* Pentium II */
+	case 7:
+	case 8:
+	case 11: /* Pentium III */
+		break;
+	case 9:
+	case 13:
+		/* Pentium M */
+		break;
+	default:
+		pr_cont("unsupported p6 CPU model %d ",
+			boot_cpu_data.x86_model);
+		return -ENODEV;
+	}
+
+	x86_pmu = p6_pmu;
+
+	if (!cpu_has_apic) {
+		pr_info("no APIC, boot with the \"lapic\" boot parameter to force-enable it.\n");
+		pr_info("no hardware sampling interrupt available.\n");
+		x86_pmu.apic = 0;
+	}
+
+	return 0;
+}
+
 static int intel_pmu_init(void)
 {
 	union cpuid10_edx edx;
@@ -1400,8 +1633,14 @@ static int intel_pmu_init(void)
 	unsigned int ebx;
 	int version;
 
-	if (!cpu_has(&boot_cpu_data, X86_FEATURE_ARCH_PERFMON))
+	if (!cpu_has(&boot_cpu_data, X86_FEATURE_ARCH_PERFMON)) {
+		/* check for P6 processor family */
+	   if (boot_cpu_data.x86 == 6) {
+		return p6_pmu_init();
+	   } else {
 		return -ENODEV;
+	   }
+	}
 
 	/*
 	 * Check whether the Architectural PerfMon supports
@@ -1561,6 +1800,7 @@ void callchain_store(struct perf_callchain_entry *entry, u64 ip)
 
 static DEFINE_PER_CPU(struct perf_callchain_entry, pmc_irq_entry);
 static DEFINE_PER_CPU(struct perf_callchain_entry, pmc_nmi_entry);
+static DEFINE_PER_CPU(int, in_nmi_frame);
 
 
 static void
@@ -1576,7 +1816,9 @@ static void backtrace_warning(void *data, char *msg)
 
 static int backtrace_stack(void *data, char *name)
 {
-	/* Process all stacks: */
+	per_cpu(in_nmi_frame, smp_processor_id()) =
+			x86_is_stack_id(NMI_STACK, name);
+
 	return 0;
 }
 
@@ -1584,6 +1826,9 @@ static void backtrace_address(void *data, unsigned long addr, int reliable)
 {
 	struct perf_callchain_entry *entry = data;
 
+	if (per_cpu(in_nmi_frame, smp_processor_id()))
+		return;
+
 	if (reliable)
 		callchain_store(entry, addr);
 }
diff --git a/arch/x86/kernel/cpu/perfctr-watchdog.c b/arch/x86/kernel/cpu/perfctr-watchdog.c
index 5c481f6205b..e60ed740d2b 100644
--- a/arch/x86/kernel/cpu/perfctr-watchdog.c
+++ b/arch/x86/kernel/cpu/perfctr-watchdog.c
@@ -803,8 +803,3 @@ int __kprobes lapic_wd_event(unsigned nmi_hz)
 	wd_ops->rearm(wd, nmi_hz);
 	return 1;
 }
-
-int lapic_watchdog_ok(void)
-{
-	return wd_ops != NULL;
-}