Merge branch 'for-rmk/perf' of... (bcc8fa83) · Commits · 戴 / test

arch/arm/include/asm/perf_event.h

+7 −0

Original line number	Diff line number	Diff line
		@@ -19,4 +19,11 @@ extern unsigned long perf_misc_flags(struct pt_regs *regs);
		#define perf_misc_flags(regs) perf_misc_flags(regs)
		#endif

		#define perf_arch_fetch_caller_regs(regs, __ip) { \
		(regs)->ARM_pc = (__ip); \
		(regs)->ARM_fp = (unsigned long) __builtin_frame_address(0); \
		(regs)->ARM_sp = current_stack_pointer; \
		(regs)->ARM_cpsr = SVC_MODE; \
		}

		#endif /* __ARM_PERF_EVENT_H__ */

arch/arm/include/asm/pmu.h

+5 −14

Original line number	Diff line number	Diff line
		@@ -24,22 +24,10 @@
		* interrupt and passed the address of the low level handler,
		* and can be used to implement any platform specific handling
		* before or after calling it.
		* @runtime_resume: an optional handler which will be called by the
		* runtime PM framework following a call to pm_runtime_get().
		* Note that if pm_runtime_get() is called more than once in
		* succession this handler will only be called once.
		* @runtime_suspend: an optional handler which will be called by the
		* runtime PM framework following a call to pm_runtime_put().
		* Note that if pm_runtime_get() is called more than once in
		* succession this handler will only be called following the
		* final call to pm_runtime_put() that actually disables the
		* hardware.
		*/
		struct arm_pmu_platdata {
		irqreturn_t (handle_irq)(int irq, void dev,
		irq_handler_t pmu_handler);
		int (runtime_resume)(struct device dev);
		int (runtime_suspend)(struct device dev);
		};

		#ifdef CONFIG_HW_PERF_EVENTS
		@@ -92,6 +80,7 @@ struct pmu_hw_events {
		struct arm_pmu {
		struct pmu pmu;
		cpumask_t active_irqs;
		cpumask_t supported_cpus;
		int *irq_affinity;
		char *name;
		irqreturn_t (handle_irq)(int irq_num, void dev);
		@@ -122,8 +111,6 @@ struct arm_pmu {

		#define to_arm_pmu(p) (container_of(p, struct arm_pmu, pmu))

		extern const struct dev_pm_ops armpmu_dev_pm_ops;

		int armpmu_register(struct arm_pmu *armpmu, int type);

		u64 armpmu_event_update(struct perf_event *event);
		@@ -158,6 +145,10 @@ struct pmu_probe_info {
		#define XSCALE_PMU_PROBE(_version, _fn) \
		PMU_PROBE(ARM_CPU_IMP_INTEL << 24 \| _version, ARM_PMU_XSCALE_MASK, _fn)

		int arm_pmu_device_probe(struct platform_device *pdev,
		const struct of_device_id *of_table,
		const struct pmu_probe_info *probe_table);

		#endif /* CONFIG_HW_PERF_EVENTS */

		#endif /* __ARM_PMU_H__ */

arch/arm/kernel/Makefile

+3 −1

Original line number	Diff line number	Diff line
		@@ -70,7 +70,9 @@ obj-$(CONFIG_CPU_PJ4) += pj4-cp0.o
		obj-$(CONFIG_CPU_PJ4B) += pj4-cp0.o
		obj-$(CONFIG_IWMMXT) += iwmmxt.o
		obj-$(CONFIG_PERF_EVENTS) += perf_regs.o perf_callchain.o
		obj-$(CONFIG_HW_PERF_EVENTS) += perf_event.o perf_event_cpu.o
		obj-$(CONFIG_HW_PERF_EVENTS) += perf_event.o \
		perf_event_xscale.o perf_event_v6.o \
		perf_event_v7.o
		CFLAGS_pj4-cp0.o := -marm
		AFLAGS_iwmmxt.o := -Wa,-mcpu=iwmmxt
		obj-$(CONFIG_ARM_CPU_TOPOLOGY) += topology.o

arch/arm/kernel/perf_event.c

+375 −33

Original line number	Diff line number	Diff line
		@@ -11,12 +11,18 @@
		*/
		#define pr_fmt(fmt) "hw perfevents: " fmt

		#include <linux/bitmap.h>
		#include <linux/cpumask.h>
		#include <linux/export.h>
		#include <linux/kernel.h>
		#include <linux/of.h>
		#include <linux/platform_device.h>
		#include <linux/pm_runtime.h>
		#include <linux/slab.h>
		#include <linux/spinlock.h>
		#include <linux/irq.h>
		#include <linux/irqdesc.h>

		#include <asm/cputype.h>
		#include <asm/irq_regs.h>
		#include <asm/pmu.h>

		@@ -229,6 +235,10 @@ armpmu_add(struct perf_event *event, int flags)
		int idx;
		int err = 0;

		/* An event following a process won't be stopped earlier */
		if (!cpumask_test_cpu(smp_processor_id(), &armpmu->supported_cpus))
		return -ENOENT;

		perf_pmu_disable(event->pmu);

		/* If we don't have a space for the counter then finish early. */
		@@ -344,20 +354,12 @@ static void
		armpmu_release_hardware(struct arm_pmu *armpmu)
		{
		armpmu->free_irq(armpmu);
		pm_runtime_put_sync(&armpmu->plat_device->dev);
		}

		static int
		armpmu_reserve_hardware(struct arm_pmu *armpmu)
		{
		int err;
		struct platform_device *pmu_device = armpmu->plat_device;

		if (!pmu_device)
		return -ENODEV;

		pm_runtime_get_sync(&pmu_device->dev);
		err = armpmu->request_irq(armpmu, armpmu_dispatch_irq);
		int err = armpmu->request_irq(armpmu, armpmu_dispatch_irq);
		if (err) {
		armpmu_release_hardware(armpmu);
		return err;
		@@ -454,6 +456,17 @@ static int armpmu_event_init(struct perf_event *event)
		int err = 0;
		atomic_t *active_events = &armpmu->active_events;

		/*
		* Reject CPU-affine events for CPUs that are of a different class to
		* that which this PMU handles. Process-following events (where
		* event->cpu == -1) can be migrated between CPUs, and thus we have to
		* reject them later (in armpmu_add) if they're scheduled on a
		* different class of CPU.
		*/
		if (event->cpu != -1 &&
		!cpumask_test_cpu(event->cpu, &armpmu->supported_cpus))
		return -ENOENT;

		/* does not support taken branch sampling */
		if (has_branch_stack(event))
		return -EOPNOTSUPP;
		@@ -489,6 +502,10 @@ static void armpmu_enable(struct pmu *pmu)
		struct pmu_hw_events *hw_events = this_cpu_ptr(armpmu->hw_events);
		int enabled = bitmap_weight(hw_events->used_mask, armpmu->num_events);

		/* For task-bound events we may be called on other CPUs */
		if (!cpumask_test_cpu(smp_processor_id(), &armpmu->supported_cpus))
		return;

		if (enabled)
		armpmu->start(armpmu);
		}
		@@ -496,34 +513,25 @@ static void armpmu_enable(struct pmu *pmu)
		static void armpmu_disable(struct pmu *pmu)
		{
		struct arm_pmu *armpmu = to_arm_pmu(pmu);
		armpmu->stop(armpmu);
		}

		#ifdef CONFIG_PM
		static int armpmu_runtime_resume(struct device *dev)
		{
		struct arm_pmu_platdata *plat = dev_get_platdata(dev);

		if (plat && plat->runtime_resume)
		return plat->runtime_resume(dev);
		/* For task-bound events we may be called on other CPUs */
		if (!cpumask_test_cpu(smp_processor_id(), &armpmu->supported_cpus))
		return;

		return 0;
		armpmu->stop(armpmu);
		}

		static int armpmu_runtime_suspend(struct device *dev)
		/*
		* In heterogeneous systems, events are specific to a particular
		* microarchitecture, and aren't suitable for another. Thus, only match CPUs of
		* the same microarchitecture.
		*/
		static int armpmu_filter_match(struct perf_event *event)
		{
		struct arm_pmu_platdata *plat = dev_get_platdata(dev);

		if (plat && plat->runtime_suspend)
		return plat->runtime_suspend(dev);

		return 0;
		struct arm_pmu *armpmu = to_arm_pmu(event->pmu);
		unsigned int cpu = smp_processor_id();
		return cpumask_test_cpu(cpu, &armpmu->supported_cpus);
		}
		#endif

		const struct dev_pm_ops armpmu_dev_pm_ops = {
		SET_RUNTIME_PM_OPS(armpmu_runtime_suspend, armpmu_runtime_resume, NULL)
		};

		static void armpmu_init(struct arm_pmu *armpmu)
		{
		@@ -539,15 +547,349 @@ static void armpmu_init(struct arm_pmu *armpmu)
		.start = armpmu_start,
		.stop = armpmu_stop,
		.read = armpmu_read,
		.filter_match = armpmu_filter_match,
		};
		}

		int armpmu_register(struct arm_pmu *armpmu, int type)
		{
		armpmu_init(armpmu);
		pm_runtime_enable(&armpmu->plat_device->dev);
		pr_info("enabled with %s PMU driver, %d counters available\n",
		armpmu->name, armpmu->num_events);
		return perf_pmu_register(&armpmu->pmu, armpmu->name, type);
		}

		/* Set at runtime when we know what CPU type we are. */
		static struct arm_pmu *__oprofile_cpu_pmu;

		/*
		* Despite the names, these two functions are CPU-specific and are used
		* by the OProfile/perf code.
		*/
		const char *perf_pmu_name(void)
		{
		if (!__oprofile_cpu_pmu)
		return NULL;

		return __oprofile_cpu_pmu->name;
		}
		EXPORT_SYMBOL_GPL(perf_pmu_name);

		int perf_num_counters(void)
		{
		int max_events = 0;

		if (__oprofile_cpu_pmu != NULL)
		max_events = __oprofile_cpu_pmu->num_events;

		return max_events;
		}
		EXPORT_SYMBOL_GPL(perf_num_counters);

		static void cpu_pmu_enable_percpu_irq(void *data)
		{
		int irq = (int )data;

		enable_percpu_irq(irq, IRQ_TYPE_NONE);
		}

		static void cpu_pmu_disable_percpu_irq(void *data)
		{
		int irq = (int )data;

		disable_percpu_irq(irq);
		}

		static void cpu_pmu_free_irq(struct arm_pmu *cpu_pmu)
		{
		int i, irq, irqs;
		struct platform_device *pmu_device = cpu_pmu->plat_device;
		struct pmu_hw_events __percpu *hw_events = cpu_pmu->hw_events;

		irqs = min(pmu_device->num_resources, num_possible_cpus());

		irq = platform_get_irq(pmu_device, 0);
		if (irq >= 0 && irq_is_percpu(irq)) {
		on_each_cpu(cpu_pmu_disable_percpu_irq, &irq, 1);
		free_percpu_irq(irq, &hw_events->percpu_pmu);
		} else {
		for (i = 0; i < irqs; ++i) {
		int cpu = i;

		if (cpu_pmu->irq_affinity)
		cpu = cpu_pmu->irq_affinity[i];

		if (!cpumask_test_and_clear_cpu(cpu, &cpu_pmu->active_irqs))
		continue;
		irq = platform_get_irq(pmu_device, i);
		if (irq >= 0)
		free_irq(irq, per_cpu_ptr(&hw_events->percpu_pmu, cpu));
		}
		}
		}

		static int cpu_pmu_request_irq(struct arm_pmu *cpu_pmu, irq_handler_t handler)
		{
		int i, err, irq, irqs;
		struct platform_device *pmu_device = cpu_pmu->plat_device;
		struct pmu_hw_events __percpu *hw_events = cpu_pmu->hw_events;

		if (!pmu_device)
		return -ENODEV;

		irqs = min(pmu_device->num_resources, num_possible_cpus());
		if (irqs < 1) {
		pr_warn_once("perf/ARM: No irqs for PMU defined, sampling events not supported\n");
		return 0;
		}

		irq = platform_get_irq(pmu_device, 0);
		if (irq >= 0 && irq_is_percpu(irq)) {
		err = request_percpu_irq(irq, handler, "arm-pmu",
		&hw_events->percpu_pmu);
		if (err) {
		pr_err("unable to request IRQ%d for ARM PMU counters\n",
		irq);
		return err;
		}
		on_each_cpu(cpu_pmu_enable_percpu_irq, &irq, 1);
		} else {
		for (i = 0; i < irqs; ++i) {
		int cpu = i;

		err = 0;
		irq = platform_get_irq(pmu_device, i);
		if (irq < 0)
		continue;

		if (cpu_pmu->irq_affinity)
		cpu = cpu_pmu->irq_affinity[i];

		/*
		* If we have a single PMU interrupt that we can't shift,
		* assume that we're running on a uniprocessor machine and
		* continue. Otherwise, continue without this interrupt.
		*/
		if (irq_set_affinity(irq, cpumask_of(cpu)) && irqs > 1) {
		pr_warn("unable to set irq affinity (irq=%d, cpu=%u)\n",
		irq, cpu);
		continue;
		}

		err = request_irq(irq, handler,
		IRQF_NOBALANCING \| IRQF_NO_THREAD, "arm-pmu",
		per_cpu_ptr(&hw_events->percpu_pmu, cpu));
		if (err) {
		pr_err("unable to request IRQ%d for ARM PMU counters\n",
		irq);
		return err;
		}

		cpumask_set_cpu(cpu, &cpu_pmu->active_irqs);
		}
		}

		return 0;
		}

		/*
		* 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 cpu_pmu_notify(struct notifier_block *b, unsigned long action,
		void *hcpu)
		{
		int cpu = (unsigned long)hcpu;
		struct arm_pmu *pmu = container_of(b, struct arm_pmu, hotplug_nb);

		if ((action & ~CPU_TASKS_FROZEN) != CPU_STARTING)
		return NOTIFY_DONE;

		if (!cpumask_test_cpu(cpu, &pmu->supported_cpus))
		return NOTIFY_DONE;

		if (pmu->reset)
		pmu->reset(pmu);
		else
		return NOTIFY_DONE;

		return NOTIFY_OK;
		}

		static int cpu_pmu_init(struct arm_pmu *cpu_pmu)
		{
		int err;
		int cpu;
		struct pmu_hw_events __percpu *cpu_hw_events;

		cpu_hw_events = alloc_percpu(struct pmu_hw_events);
		if (!cpu_hw_events)
		return -ENOMEM;

		cpu_pmu->hotplug_nb.notifier_call = cpu_pmu_notify;
		err = register_cpu_notifier(&cpu_pmu->hotplug_nb);
		if (err)
		goto out_hw_events;

		for_each_possible_cpu(cpu) {
		struct pmu_hw_events *events = per_cpu_ptr(cpu_hw_events, cpu);
		raw_spin_lock_init(&events->pmu_lock);
		events->percpu_pmu = cpu_pmu;
		}

		cpu_pmu->hw_events = cpu_hw_events;
		cpu_pmu->request_irq = cpu_pmu_request_irq;
		cpu_pmu->free_irq = cpu_pmu_free_irq;

		/* Ensure the PMU has sane values out of reset. */
		if (cpu_pmu->reset)
		on_each_cpu_mask(&cpu_pmu->supported_cpus, cpu_pmu->reset,
		cpu_pmu, 1);

		/* If no interrupts available, set the corresponding capability flag */
		if (!platform_get_irq(cpu_pmu->plat_device, 0))
		cpu_pmu->pmu.capabilities \|= PERF_PMU_CAP_NO_INTERRUPT;

		return 0;

		out_hw_events:
		free_percpu(cpu_hw_events);
		return err;
		}

		static void cpu_pmu_destroy(struct arm_pmu *cpu_pmu)
		{
		unregister_cpu_notifier(&cpu_pmu->hotplug_nb);
		free_percpu(cpu_pmu->hw_events);
		}

		/*
		* CPU PMU identification and probing.
		*/
		static int probe_current_pmu(struct arm_pmu *pmu,
		const struct pmu_probe_info *info)
		{
		int cpu = get_cpu();
		unsigned int cpuid = read_cpuid_id();
		int ret = -ENODEV;

		pr_info("probing PMU on CPU %d\n", cpu);

		for (; info->init != NULL; info++) {
		if ((cpuid & info->mask) != info->cpuid)
		continue;
		ret = info->init(pmu);
		break;
		}

		put_cpu();
		return ret;
		}

		static int of_pmu_irq_cfg(struct arm_pmu *pmu)
		{
		int i, irq, *irqs;
		struct platform_device *pdev = pmu->plat_device;

		/* Don't bother with PPIs; they're already affine */
		irq = platform_get_irq(pdev, 0);
		if (irq >= 0 && irq_is_percpu(irq))
		return 0;

		irqs = kcalloc(pdev->num_resources, sizeof(*irqs), GFP_KERNEL);
		if (!irqs)
		return -ENOMEM;

		for (i = 0; i < pdev->num_resources; ++i) {
		struct device_node *dn;
		int cpu;

		dn = of_parse_phandle(pdev->dev.of_node, "interrupt-affinity",
		i);
		if (!dn) {
		pr_warn("Failed to parse %s/interrupt-affinity[%d]\n",
		of_node_full_name(pdev->dev.of_node), i);
		break;
		}

		for_each_possible_cpu(cpu)
		if (arch_find_n_match_cpu_physical_id(dn, cpu, NULL))
		break;

		of_node_put(dn);
		if (cpu >= nr_cpu_ids) {
		pr_warn("Failed to find logical CPU for %s\n",
		dn->name);
		break;
		}

		irqs[i] = cpu;
		cpumask_set_cpu(cpu, &pmu->supported_cpus);
		}

		if (i == pdev->num_resources) {
		pmu->irq_affinity = irqs;
		} else {
		kfree(irqs);
		cpumask_setall(&pmu->supported_cpus);
		}

		return 0;
		}

		int arm_pmu_device_probe(struct platform_device *pdev,
		const struct of_device_id *of_table,
		const struct pmu_probe_info *probe_table)
		{
		const struct of_device_id *of_id;
		const int (init_fn)(struct arm_pmu );
		struct device_node *node = pdev->dev.of_node;
		struct arm_pmu *pmu;
		int ret = -ENODEV;

		pmu = kzalloc(sizeof(struct arm_pmu), GFP_KERNEL);
		if (!pmu) {
		pr_info("failed to allocate PMU device!\n");
		return -ENOMEM;
		}

		if (!__oprofile_cpu_pmu)
		__oprofile_cpu_pmu = pmu;

		pmu->plat_device = pdev;

		if (node && (of_id = of_match_node(of_table, pdev->dev.of_node))) {
		init_fn = of_id->data;

		ret = of_pmu_irq_cfg(pmu);
		if (!ret)
		ret = init_fn(pmu);
		} else {
		ret = probe_current_pmu(pmu, probe_table);
		cpumask_setall(&pmu->supported_cpus);
		}

		if (ret) {
		pr_info("failed to probe PMU!\n");
		goto out_free;
		}

		ret = cpu_pmu_init(pmu);
		if (ret)
		goto out_free;

		ret = armpmu_register(pmu, -1);
		if (ret)
		goto out_destroy;

		return 0;

		out_destroy:
		cpu_pmu_destroy(pmu);
		out_free:
		pr_info("failed to register PMU devices!\n");
		kfree(pmu);
		return ret;
		}

arch/arm/kernel/perf_event_cpu.c

deleted100644 → 0

+0 −415

Original line number	Diff line number	Diff line
		/*
		* This program is free software; you can redistribute it and/or modify
		* it under the terms of the GNU General Public License version 2 as
		* published by the Free Software Foundation.
		*
		* This program is distributed in the hope that it will be useful,
		* but WITHOUT ANY WARRANTY; without even the implied warranty of
		* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
		* GNU General Public License for more details.
		*
		* You should have received a copy of the GNU General Public License
		* along with this program; if not, write to the Free Software
		* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
		*
		* Copyright (C) 2012 ARM Limited
		*
		* Author: Will Deacon <will.deacon@arm.com>
		*/
		#define pr_fmt(fmt) "CPU PMU: " fmt

		#include <linux/bitmap.h>
		#include <linux/export.h>
		#include <linux/kernel.h>
		#include <linux/of.h>
		#include <linux/platform_device.h>
		#include <linux/slab.h>
		#include <linux/spinlock.h>
		#include <linux/irq.h>
		#include <linux/irqdesc.h>

		#include <asm/cputype.h>
		#include <asm/irq_regs.h>
		#include <asm/pmu.h>

		/* Set at runtime when we know what CPU type we are. */
		static struct arm_pmu *cpu_pmu;

		/*
		* Despite the names, these two functions are CPU-specific and are used
		* by the OProfile/perf code.
		*/
		const char *perf_pmu_name(void)
		{
		if (!cpu_pmu)
		return NULL;

		return cpu_pmu->name;
		}
		EXPORT_SYMBOL_GPL(perf_pmu_name);

		int perf_num_counters(void)
		{
		int max_events = 0;

		if (cpu_pmu != NULL)
		max_events = cpu_pmu->num_events;

		return max_events;
		}
		EXPORT_SYMBOL_GPL(perf_num_counters);

		/* Include the PMU-specific implementations. */
		#include "perf_event_xscale.c"
		#include "perf_event_v6.c"
		#include "perf_event_v7.c"

		static void cpu_pmu_enable_percpu_irq(void *data)
		{
		int irq = (int )data;

		enable_percpu_irq(irq, IRQ_TYPE_NONE);
		}

		static void cpu_pmu_disable_percpu_irq(void *data)
		{
		int irq = (int )data;

		disable_percpu_irq(irq);
		}

		static void cpu_pmu_free_irq(struct arm_pmu *cpu_pmu)
		{
		int i, irq, irqs;
		struct platform_device *pmu_device = cpu_pmu->plat_device;
		struct pmu_hw_events __percpu *hw_events = cpu_pmu->hw_events;

		irqs = min(pmu_device->num_resources, num_possible_cpus());

		irq = platform_get_irq(pmu_device, 0);
		if (irq >= 0 && irq_is_percpu(irq)) {
		on_each_cpu(cpu_pmu_disable_percpu_irq, &irq, 1);
		free_percpu_irq(irq, &hw_events->percpu_pmu);
		} else {
		for (i = 0; i < irqs; ++i) {
		int cpu = i;

		if (cpu_pmu->irq_affinity)
		cpu = cpu_pmu->irq_affinity[i];

		if (!cpumask_test_and_clear_cpu(cpu, &cpu_pmu->active_irqs))
		continue;
		irq = platform_get_irq(pmu_device, i);
		if (irq >= 0)
		free_irq(irq, per_cpu_ptr(&hw_events->percpu_pmu, cpu));
		}
		}
		}

		static int cpu_pmu_request_irq(struct arm_pmu *cpu_pmu, irq_handler_t handler)
		{
		int i, err, irq, irqs;
		struct platform_device *pmu_device = cpu_pmu->plat_device;
		struct pmu_hw_events __percpu *hw_events = cpu_pmu->hw_events;

		if (!pmu_device)
		return -ENODEV;

		irqs = min(pmu_device->num_resources, num_possible_cpus());
		if (irqs < 1) {
		pr_warn_once("perf/ARM: No irqs for PMU defined, sampling events not supported\n");
		return 0;
		}

		irq = platform_get_irq(pmu_device, 0);
		if (irq >= 0 && irq_is_percpu(irq)) {
		err = request_percpu_irq(irq, handler, "arm-pmu",
		&hw_events->percpu_pmu);
		if (err) {
		pr_err("unable to request IRQ%d for ARM PMU counters\n",
		irq);
		return err;
		}
		on_each_cpu(cpu_pmu_enable_percpu_irq, &irq, 1);
		} else {
		for (i = 0; i < irqs; ++i) {
		int cpu = i;

		err = 0;
		irq = platform_get_irq(pmu_device, i);
		if (irq < 0)
		continue;

		if (cpu_pmu->irq_affinity)
		cpu = cpu_pmu->irq_affinity[i];

		/*
		* If we have a single PMU interrupt that we can't shift,
		* assume that we're running on a uniprocessor machine and
		* continue. Otherwise, continue without this interrupt.
		*/
		if (irq_set_affinity(irq, cpumask_of(cpu)) && irqs > 1) {
		pr_warn("unable to set irq affinity (irq=%d, cpu=%u)\n",
		irq, cpu);
		continue;
		}

		err = request_irq(irq, handler,
		IRQF_NOBALANCING \| IRQF_NO_THREAD, "arm-pmu",
		per_cpu_ptr(&hw_events->percpu_pmu, cpu));
		if (err) {
		pr_err("unable to request IRQ%d for ARM PMU counters\n",
		irq);
		return err;
		}

		cpumask_set_cpu(cpu, &cpu_pmu->active_irqs);
		}
		}

		return 0;
		}

		/*
		* 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 cpu_pmu_notify(struct notifier_block *b, unsigned long action,
		void *hcpu)
		{
		struct arm_pmu *pmu = container_of(b, struct arm_pmu, hotplug_nb);

		if ((action & ~CPU_TASKS_FROZEN) != CPU_STARTING)
		return NOTIFY_DONE;

		if (pmu->reset)
		pmu->reset(pmu);
		else
		return NOTIFY_DONE;

		return NOTIFY_OK;
		}

		static int cpu_pmu_init(struct arm_pmu *cpu_pmu)
		{
		int err;
		int cpu;
		struct pmu_hw_events __percpu *cpu_hw_events;

		cpu_hw_events = alloc_percpu(struct pmu_hw_events);
		if (!cpu_hw_events)
		return -ENOMEM;

		cpu_pmu->hotplug_nb.notifier_call = cpu_pmu_notify;
		err = register_cpu_notifier(&cpu_pmu->hotplug_nb);
		if (err)
		goto out_hw_events;

		for_each_possible_cpu(cpu) {
		struct pmu_hw_events *events = per_cpu_ptr(cpu_hw_events, cpu);
		raw_spin_lock_init(&events->pmu_lock);
		events->percpu_pmu = cpu_pmu;
		}

		cpu_pmu->hw_events = cpu_hw_events;
		cpu_pmu->request_irq = cpu_pmu_request_irq;
		cpu_pmu->free_irq = cpu_pmu_free_irq;

		/* Ensure the PMU has sane values out of reset. */
		if (cpu_pmu->reset)
		on_each_cpu(cpu_pmu->reset, cpu_pmu, 1);

		/* If no interrupts available, set the corresponding capability flag */
		if (!platform_get_irq(cpu_pmu->plat_device, 0))
		cpu_pmu->pmu.capabilities \|= PERF_PMU_CAP_NO_INTERRUPT;

		return 0;

		out_hw_events:
		free_percpu(cpu_hw_events);
		return err;
		}

		static void cpu_pmu_destroy(struct arm_pmu *cpu_pmu)
		{
		unregister_cpu_notifier(&cpu_pmu->hotplug_nb);
		free_percpu(cpu_pmu->hw_events);
		}

		/*
		* PMU platform driver and devicetree bindings.
		*/
		static const struct of_device_id cpu_pmu_of_device_ids[] = {
		{.compatible = "arm,cortex-a17-pmu", .data = armv7_a17_pmu_init},
		{.compatible = "arm,cortex-a15-pmu", .data = armv7_a15_pmu_init},
		{.compatible = "arm,cortex-a12-pmu", .data = armv7_a12_pmu_init},
		{.compatible = "arm,cortex-a9-pmu", .data = armv7_a9_pmu_init},
		{.compatible = "arm,cortex-a8-pmu", .data = armv7_a8_pmu_init},
		{.compatible = "arm,cortex-a7-pmu", .data = armv7_a7_pmu_init},
		{.compatible = "arm,cortex-a5-pmu", .data = armv7_a5_pmu_init},
		{.compatible = "arm,arm11mpcore-pmu", .data = armv6mpcore_pmu_init},
		{.compatible = "arm,arm1176-pmu", .data = armv6_1176_pmu_init},
		{.compatible = "arm,arm1136-pmu", .data = armv6_1136_pmu_init},
		{.compatible = "qcom,krait-pmu", .data = krait_pmu_init},
		{.compatible = "qcom,scorpion-pmu", .data = scorpion_pmu_init},
		{.compatible = "qcom,scorpion-mp-pmu", .data = scorpion_mp_pmu_init},
		{},
		};

		static struct platform_device_id cpu_pmu_plat_device_ids[] = {
		{.name = "arm-pmu"},
		{.name = "armv6-pmu"},
		{.name = "armv7-pmu"},
		{.name = "xscale-pmu"},
		{},
		};

		static const struct pmu_probe_info pmu_probe_table[] = {
		ARM_PMU_PROBE(ARM_CPU_PART_ARM1136, armv6_1136_pmu_init),
		ARM_PMU_PROBE(ARM_CPU_PART_ARM1156, armv6_1156_pmu_init),
		ARM_PMU_PROBE(ARM_CPU_PART_ARM1176, armv6_1176_pmu_init),
		ARM_PMU_PROBE(ARM_CPU_PART_ARM11MPCORE, armv6mpcore_pmu_init),
		ARM_PMU_PROBE(ARM_CPU_PART_CORTEX_A8, armv7_a8_pmu_init),
		ARM_PMU_PROBE(ARM_CPU_PART_CORTEX_A9, armv7_a9_pmu_init),
		XSCALE_PMU_PROBE(ARM_CPU_XSCALE_ARCH_V1, xscale1pmu_init),
		XSCALE_PMU_PROBE(ARM_CPU_XSCALE_ARCH_V2, xscale2pmu_init),
		{ /* sentinel value */ }
		};

		/*
		* CPU PMU identification and probing.
		*/
		static int probe_current_pmu(struct arm_pmu *pmu)
		{
		int cpu = get_cpu();
		unsigned int cpuid = read_cpuid_id();
		int ret = -ENODEV;
		const struct pmu_probe_info *info;

		pr_info("probing PMU on CPU %d\n", cpu);

		for (info = pmu_probe_table; info->init != NULL; info++) {
		if ((cpuid & info->mask) != info->cpuid)
		continue;
		ret = info->init(pmu);
		break;
		}

		put_cpu();
		return ret;
		}

		static int of_pmu_irq_cfg(struct platform_device *pdev)
		{
		int i;
		int irqs = kcalloc(pdev->num_resources, sizeof(irqs), GFP_KERNEL);

		if (!irqs)
		return -ENOMEM;

		for (i = 0; i < pdev->num_resources; ++i) {
		struct device_node *dn;
		int cpu;

		dn = of_parse_phandle(pdev->dev.of_node, "interrupt-affinity",
		i);
		if (!dn) {
		pr_warn("Failed to parse %s/interrupt-affinity[%d]\n",
		of_node_full_name(dn), i);
		break;
		}

		for_each_possible_cpu(cpu)
		if (arch_find_n_match_cpu_physical_id(dn, cpu, NULL))
		break;

		of_node_put(dn);
		if (cpu >= nr_cpu_ids) {
		pr_warn("Failed to find logical CPU for %s\n",
		dn->name);
		break;
		}

		irqs[i] = cpu;
		}

		if (i == pdev->num_resources)
		cpu_pmu->irq_affinity = irqs;
		else
		kfree(irqs);

		return 0;
		}

		static int cpu_pmu_device_probe(struct platform_device *pdev)
		{
		const struct of_device_id *of_id;
		const int (init_fn)(struct arm_pmu );
		struct device_node *node = pdev->dev.of_node;
		struct arm_pmu *pmu;
		int ret = -ENODEV;

		if (cpu_pmu) {
		pr_info("attempt to register multiple PMU devices!\n");
		return -ENOSPC;
		}

		pmu = kzalloc(sizeof(struct arm_pmu), GFP_KERNEL);
		if (!pmu) {
		pr_info("failed to allocate PMU device!\n");
		return -ENOMEM;
		}

		cpu_pmu = pmu;
		cpu_pmu->plat_device = pdev;

		if (node && (of_id = of_match_node(cpu_pmu_of_device_ids, pdev->dev.of_node))) {
		init_fn = of_id->data;

		ret = of_pmu_irq_cfg(pdev);
		if (!ret)
		ret = init_fn(pmu);
		} else {
		ret = probe_current_pmu(pmu);
		}

		if (ret) {
		pr_info("failed to probe PMU!\n");
		goto out_free;
		}

		ret = cpu_pmu_init(cpu_pmu);
		if (ret)
		goto out_free;

		ret = armpmu_register(cpu_pmu, -1);
		if (ret)
		goto out_destroy;

		return 0;

		out_destroy:
		cpu_pmu_destroy(cpu_pmu);
		out_free:
		pr_info("failed to register PMU devices!\n");
		kfree(pmu);
		return ret;
		}

		static struct platform_driver cpu_pmu_driver = {
		.driver = {
		.name = "arm-pmu",
		.pm = &armpmu_dev_pm_ops,
		.of_match_table = cpu_pmu_of_device_ids,
		},
		.probe = cpu_pmu_device_probe,
		.id_table = cpu_pmu_plat_device_ids,
		};

		static int __init register_pmu_driver(void)
		{
		return platform_driver_register(&cpu_pmu_driver);
		}
		device_initcall(register_pmu_driver);

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