Merge tag 'v3.3-rc7' into sched/core

Merge reason: merge back final fixes, prepare for the merge window.

Signed-off-by: Ingo Molnar <mingo@elte.hu>

5 files changed, 64 insertions, 35 deletions

diff --git a/arch/arm/kernel/ecard.c b/arch/arm/kernel/ecard.c
index 4dd0edab6a65..1651d4950744 100644
--- a/arch/arm/kernel/ecard.c
+++ b/arch/arm/kernel/ecard.c
@@ -242,6 +242,7 @@ static void ecard_init_pgtables(struct mm_struct *mm)
 
 	memcpy(dst_pgd, src_pgd, sizeof(pgd_t) * (EASI_SIZE / PGDIR_SIZE));
 
+	vma.vm_flags = VM_EXEC;
 	vma.vm_mm = mm;
 
 	flush_tlb_range(&vma, IO_START, IO_START + IO_SIZE);
diff --git a/arch/arm/kernel/perf_event.c b/arch/arm/kernel/perf_event.c
index 5bb91bf3d47f..b2abfa18f137 100644
--- a/arch/arm/kernel/perf_event.c
+++ b/arch/arm/kernel/perf_event.c
@@ -180,7 +180,7 @@ armpmu_event_set_period(struct perf_event *event,
 u64
 armpmu_event_update(struct perf_event *event,
 		    struct hw_perf_event *hwc,
-		    int idx, int overflow)
+		    int idx)
 {
 	struct arm_pmu *armpmu = to_arm_pmu(event->pmu);
 	u64 delta, prev_raw_count, new_raw_count;
@@ -193,13 +193,7 @@ again:
 			     new_raw_count) != prev_raw_count)
 		goto again;
 
-	new_raw_count &= armpmu->max_period;
-	prev_raw_count &= armpmu->max_period;
-
-	if (overflow)
-		delta = armpmu->max_period - prev_raw_count + new_raw_count + 1;
-	else
-		delta = new_raw_count - prev_raw_count;
+	delta = (new_raw_count - prev_raw_count) & armpmu->max_period;
 
 	local64_add(delta, &event->count);
 	local64_sub(delta, &hwc->period_left);
@@ -216,7 +210,7 @@ armpmu_read(struct perf_event *event)
 	if (hwc->idx < 0)
 		return;
 
-	armpmu_event_update(event, hwc, hwc->idx, 0);
+	armpmu_event_update(event, hwc, hwc->idx);
 }
 
 static void
@@ -232,7 +226,7 @@ armpmu_stop(struct perf_event *event, int flags)
 	if (!(hwc->state & PERF_HES_STOPPED)) {
 		armpmu->disable(hwc, hwc->idx);
 		barrier(); /* why? */
-		armpmu_event_update(event, hwc, hwc->idx, 0);
+		armpmu_event_update(event, hwc, hwc->idx);
 		hwc->state |= PERF_HES_STOPPED | PERF_HES_UPTODATE;
 	}
 }
@@ -518,7 +512,13 @@ __hw_perf_event_init(struct perf_event *event)
 	hwc->config_base	    |= (unsigned long)mapping;
 
 	if (!hwc->sample_period) {
-		hwc->sample_period  = armpmu->max_period;
+		/*
+		 * For non-sampling runs, limit the sample_period to half
+		 * of the counter width. That way, the new counter value
+		 * is far less likely to overtake the previous one unless
+		 * you have some serious IRQ latency issues.
+		 */
+		hwc->sample_period  = armpmu->max_period >> 1;
 		hwc->last_period    = hwc->sample_period;
 		local64_set(&hwc->period_left, hwc->sample_period);
 	}
@@ -680,6 +680,28 @@ static void __init cpu_pmu_init(struct arm_pmu *armpmu)
 }
 
 /*
+ * PMU hardware loses all context when a CPU goes offline.
+ * When a CPU is hotplugged back in, since some hardware registers are
+ * UNKNOWN at reset, the PMU must be explicitly reset to avoid reading
+ * junk values out of them.
+ */
+static int __cpuinit pmu_cpu_notify(struct notifier_block *b,
+					unsigned long action, void *hcpu)
+{
+	if ((action & ~CPU_TASKS_FROZEN) != CPU_STARTING)
+		return NOTIFY_DONE;
+
+	if (cpu_pmu && cpu_pmu->reset)
+		cpu_pmu->reset(NULL);
+
+	return NOTIFY_OK;
+}
+
+static struct notifier_block __cpuinitdata pmu_cpu_notifier = {
+	.notifier_call = pmu_cpu_notify,
+};
+
+/*
  * CPU PMU identification and registration.
  */
 static int __init
@@ -730,6 +752,7 @@ init_hw_perf_events(void)
 		pr_info("enabled with %s PMU driver, %d counters available\n",
 			cpu_pmu->name, cpu_pmu->num_events);
 		cpu_pmu_init(cpu_pmu);
+		register_cpu_notifier(&pmu_cpu_notifier);
 		armpmu_register(cpu_pmu, "cpu", PERF_TYPE_RAW);
 	} else {
 		pr_info("no hardware support available\n");
diff --git a/arch/arm/kernel/perf_event_v6.c b/arch/arm/kernel/perf_event_v6.c
index 533be9930ec2..b78af0cc6ef3 100644
--- a/arch/arm/kernel/perf_event_v6.c
+++ b/arch/arm/kernel/perf_event_v6.c
@@ -467,23 +467,6 @@ armv6pmu_enable_event(struct hw_perf_event *hwc,
 	raw_spin_unlock_irqrestore(&events->pmu_lock, flags);
 }
 
-static int counter_is_active(unsigned long pmcr, int idx)
-{
-	unsigned long mask = 0;
-	if (idx == ARMV6_CYCLE_COUNTER)
-		mask = ARMV6_PMCR_CCOUNT_IEN;
-	else if (idx == ARMV6_COUNTER0)
-		mask = ARMV6_PMCR_COUNT0_IEN;
-	else if (idx == ARMV6_COUNTER1)
-		mask = ARMV6_PMCR_COUNT1_IEN;
-
-	if (mask)
-		return pmcr & mask;
-
-	WARN_ONCE(1, "invalid counter number (%d)\n", idx);
-	return 0;
-}
-
 static irqreturn_t
 armv6pmu_handle_irq(int irq_num,
 		    void *dev)
@@ -513,7 +496,8 @@ armv6pmu_handle_irq(int irq_num,
 		struct perf_event *event = cpuc->events[idx];
 		struct hw_perf_event *hwc;
 
-		if (!counter_is_active(pmcr, idx))
+		/* Ignore if we don't have an event. */
+		if (!event)
 			continue;
 
 		/*
@@ -524,7 +508,7 @@ armv6pmu_handle_irq(int irq_num,
 			continue;
 
 		hwc = &event->hw;
-		armpmu_event_update(event, hwc, idx, 1);
+		armpmu_event_update(event, hwc, idx);
 		data.period = event->hw.last_period;
 		if (!armpmu_event_set_period(event, hwc, idx))
 			continue;
diff --git a/arch/arm/kernel/perf_event_v7.c b/arch/arm/kernel/perf_event_v7.c
index 6933244c68f9..4d7095af2ab3 100644
--- a/arch/arm/kernel/perf_event_v7.c
+++ b/arch/arm/kernel/perf_event_v7.c
@@ -809,6 +809,11 @@ static inline int armv7_pmnc_disable_intens(int idx)
 
 	counter = ARMV7_IDX_TO_COUNTER(idx);
 	asm volatile("mcr p15, 0, %0, c9, c14, 2" : : "r" (BIT(counter)));
+	isb();
+	/* Clear the overflow flag in case an interrupt is pending. */
+	asm volatile("mcr p15, 0, %0, c9, c12, 3" : : "r" (BIT(counter)));
+	isb();
+
 	return idx;
 }
 
@@ -955,6 +960,10 @@ static irqreturn_t armv7pmu_handle_irq(int irq_num, void *dev)
 		struct perf_event *event = cpuc->events[idx];
 		struct hw_perf_event *hwc;
 
+		/* Ignore if we don't have an event. */
+		if (!event)
+			continue;
+
 		/*
 		 * We have a single interrupt for all counters. Check that
 		 * each counter has overflowed before we process it.
@@ -963,7 +972,7 @@ static irqreturn_t armv7pmu_handle_irq(int irq_num, void *dev)
 			continue;
 
 		hwc = &event->hw;
-		armpmu_event_update(event, hwc, idx, 1);
+		armpmu_event_update(event, hwc, idx);
 		data.period = event->hw.last_period;
 		if (!armpmu_event_set_period(event, hwc, idx))
 			continue;
diff --git a/arch/arm/kernel/perf_event_xscale.c b/arch/arm/kernel/perf_event_xscale.c
index 3b99d8269829..71a21e6712f5 100644
--- a/arch/arm/kernel/perf_event_xscale.c
+++ b/arch/arm/kernel/perf_event_xscale.c
@@ -255,11 +255,14 @@ xscale1pmu_handle_irq(int irq_num, void *dev)
 		struct perf_event *event = cpuc->events[idx];
 		struct hw_perf_event *hwc;
 
+		if (!event)
+			continue;
+
 		if (!xscale1_pmnc_counter_has_overflowed(pmnc, idx))
 			continue;
 
 		hwc = &event->hw;
-		armpmu_event_update(event, hwc, idx, 1);
+		armpmu_event_update(event, hwc, idx);
 		data.period = event->hw.last_period;
 		if (!armpmu_event_set_period(event, hwc, idx))
 			continue;
@@ -592,11 +595,14 @@ xscale2pmu_handle_irq(int irq_num, void *dev)
 		struct perf_event *event = cpuc->events[idx];
 		struct hw_perf_event *hwc;
 
-		if (!xscale2_pmnc_counter_has_overflowed(pmnc, idx))
+		if (!event)
+			continue;
+
+		if (!xscale2_pmnc_counter_has_overflowed(of_flags, idx))
 			continue;
 
 		hwc = &event->hw;
-		armpmu_event_update(event, hwc, idx, 1);
+		armpmu_event_update(event, hwc, idx);
 		data.period = event->hw.last_period;
 		if (!armpmu_event_set_period(event, hwc, idx))
 			continue;
@@ -663,7 +669,7 @@ xscale2pmu_enable_event(struct hw_perf_event *hwc, int idx)
 static void
 xscale2pmu_disable_event(struct hw_perf_event *hwc, int idx)
 {
-	unsigned long flags, ien, evtsel;
+	unsigned long flags, ien, evtsel, of_flags;
 	struct pmu_hw_events *events = cpu_pmu->get_hw_events();
 
 	ien = xscale2pmu_read_int_enable();
@@ -672,26 +678,31 @@ xscale2pmu_disable_event(struct hw_perf_event *hwc, int idx)
 	switch (idx) {
 	case XSCALE_CYCLE_COUNTER:
 		ien &= ~XSCALE2_CCOUNT_INT_EN;
+		of_flags = XSCALE2_CCOUNT_OVERFLOW;
 		break;
 	case XSCALE_COUNTER0:
 		ien &= ~XSCALE2_COUNT0_INT_EN;
 		evtsel &= ~XSCALE2_COUNT0_EVT_MASK;
 		evtsel |= XSCALE_PERFCTR_UNUSED << XSCALE2_COUNT0_EVT_SHFT;
+		of_flags = XSCALE2_COUNT0_OVERFLOW;
 		break;
 	case XSCALE_COUNTER1:
 		ien &= ~XSCALE2_COUNT1_INT_EN;
 		evtsel &= ~XSCALE2_COUNT1_EVT_MASK;
 		evtsel |= XSCALE_PERFCTR_UNUSED << XSCALE2_COUNT1_EVT_SHFT;
+		of_flags = XSCALE2_COUNT1_OVERFLOW;
 		break;
 	case XSCALE_COUNTER2:
 		ien &= ~XSCALE2_COUNT2_INT_EN;
 		evtsel &= ~XSCALE2_COUNT2_EVT_MASK;
 		evtsel |= XSCALE_PERFCTR_UNUSED << XSCALE2_COUNT2_EVT_SHFT;
+		of_flags = XSCALE2_COUNT2_OVERFLOW;
 		break;
 	case XSCALE_COUNTER3:
 		ien &= ~XSCALE2_COUNT3_INT_EN;
 		evtsel &= ~XSCALE2_COUNT3_EVT_MASK;
 		evtsel |= XSCALE_PERFCTR_UNUSED << XSCALE2_COUNT3_EVT_SHFT;
+		of_flags = XSCALE2_COUNT3_OVERFLOW;
 		break;
 	default:
 		WARN_ONCE(1, "invalid counter number (%d)\n", idx);
@@ -701,6 +712,7 @@ xscale2pmu_disable_event(struct hw_perf_event *hwc, int idx)
 	raw_spin_lock_irqsave(&events->pmu_lock, flags);
 	xscale2pmu_write_event_select(evtsel);
 	xscale2pmu_write_int_enable(ien);
+	xscale2pmu_write_overflow_flags(of_flags);
 	raw_spin_unlock_irqrestore(&events->pmu_lock, flags);
 }