Add support for irq registration when pmu interrupt is percpu. Signed-off-by: Vinayak Kale <vk...@apm.com> Signed-off-by: Tuan Phan <tp...@apm.com> --- arch/arm64/kernel/perf_event.c | 109 +++++++++++++++++++++++++++++----------- 1 file changed, 81 insertions(+), 28 deletions(-)
diff --git a/arch/arm64/kernel/perf_event.c b/arch/arm64/kernel/perf_event.c index cea1594..e60dae3 100644 --- a/arch/arm64/kernel/perf_event.c +++ b/arch/arm64/kernel/perf_event.c @@ -44,6 +44,7 @@ static DEFINE_PER_CPU(struct perf_event * [ARMPMU_MAX_HWEVENTS], hw_events); static DEFINE_PER_CPU(unsigned long [BITS_TO_LONGS(ARMPMU_MAX_HWEVENTS)], used_mask); static DEFINE_PER_CPU(struct pmu_hw_events, cpu_hw_events); +static bool is_percpuirq; #define to_arm_pmu(p) (container_of(p, struct arm_pmu, pmu)) @@ -363,22 +364,51 @@ validate_group(struct perf_event *event) } static void +armpmu_disable_percpu_irq(void *data) +{ + struct arm_pmu *armpmu = (struct arm_pmu *)data; + struct platform_device *pmu_device = armpmu->plat_device; + int irq = platform_get_irq(pmu_device, 0); + + cpumask_test_and_clear_cpu(smp_processor_id(), &armpmu->active_irqs); + disable_percpu_irq(irq); +} + +static void armpmu_release_hardware(struct arm_pmu *armpmu) { int i, irq, irqs; struct platform_device *pmu_device = armpmu->plat_device; - irqs = min(pmu_device->num_resources, num_possible_cpus()); + irq = platform_get_irq(pmu_device, 0); - for (i = 0; i < irqs; ++i) { - if (!cpumask_test_and_clear_cpu(i, &armpmu->active_irqs)) - continue; - irq = platform_get_irq(pmu_device, i); - if (irq >= 0) - free_irq(irq, armpmu); + if (is_percpuirq) { + on_each_cpu(armpmu_disable_percpu_irq, (void *)armpmu, 1); + free_percpu_irq(irq, &cpu_hw_events); + } else { + irqs = min(pmu_device->num_resources, num_possible_cpus()); + + for (i = 0; i < irqs; ++i) { + if (!cpumask_test_and_clear_cpu(i, &armpmu->active_irqs)) + continue; + irq = platform_get_irq(pmu_device, i); + if (irq >= 0) + free_irq(irq, armpmu); + } } } +static void +armpmu_enable_percpu_irq(void *data) +{ + struct arm_pmu *armpmu = (struct arm_pmu *)data; + struct platform_device *pmu_device = armpmu->plat_device; + int irq = platform_get_irq(pmu_device, 0); + + enable_percpu_irq(irq, 0); + cpumask_set_cpu(smp_processor_id(), &armpmu->active_irqs); +} + static int armpmu_reserve_hardware(struct arm_pmu *armpmu) { @@ -396,34 +426,57 @@ armpmu_reserve_hardware(struct arm_pmu *armpmu) return -ENODEV; } - for (i = 0; i < irqs; ++i) { - err = 0; - irq = platform_get_irq(pmu_device, i); - if (irq < 0) - continue; + irq = platform_get_irq(pmu_device, 0); - /* - * 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(i)) && irqs > 1) { - pr_warning("unable to set irq affinity (irq=%d, cpu=%u)\n", - irq, i); - continue; - } + /* + * Try 'request_percpu_irq' first. If it's return value indicates + * that irq is not percpu then try 'request_irq' + */ + err = request_percpu_irq(irq, armpmu->handle_irq, + "arm-pmu", &cpu_hw_events); + if (err != -EPERM) { + is_percpuirq = true; - err = request_irq(irq, armpmu->handle_irq, - IRQF_NOBALANCING, - "arm-pmu", armpmu); if (err) { - pr_err("unable to request IRQ%d for ARM PMU counters\n", - irq); + pr_err("unable to request percpu IRQ%d for ARM PMU counters\n", + irq); armpmu_release_hardware(armpmu); return err; } - cpumask_set_cpu(i, &armpmu->active_irqs); + on_each_cpu(armpmu_enable_percpu_irq, (void *)armpmu, 1); + } else { + is_percpuirq = false; + + for (i = 0; i < irqs; ++i) { + err = 0; + irq = platform_get_irq(pmu_device, i); + if (irq < 0) + continue; + + /* + * 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(i)) && irqs > 1) { + pr_warning("unable to set irq affinity (irq=%d, cpu=%u)\n", + irq, i); + continue; + } + + err = request_irq(irq, armpmu->handle_irq, + IRQF_NOBALANCING, + "arm-pmu", armpmu); + if (err) { + pr_err("unable to request IRQ%d for ARM PMU counters\n", + irq); + armpmu_release_hardware(armpmu); + return err; + } + + cpumask_set_cpu(i, &armpmu->active_irqs); + } } return 0; -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/