diff options
| -rw-r--r-- | arch/arm/include/asm/pmu.h | 1 | ||||
| -rw-r--r-- | arch/arm/kernel/perf_event.c | 25 | ||||
| -rw-r--r-- | arch/arm/kernel/perf_event_cpu.c | 15 |
3 files changed, 38 insertions, 3 deletions
diff --git a/arch/arm/include/asm/pmu.h b/arch/arm/include/asm/pmu.h index 675e4ab79f68..ecad26e7a68f 100644 --- a/arch/arm/include/asm/pmu.h +++ b/arch/arm/include/asm/pmu.h @@ -92,6 +92,7 @@ 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); diff --git a/arch/arm/kernel/perf_event.c b/arch/arm/kernel/perf_event.c index 4a86a0133ac3..9b536be74f7b 100644 --- a/arch/arm/kernel/perf_event.c +++ b/arch/arm/kernel/perf_event.c @@ -11,6 +11,7 @@ */ #define pr_fmt(fmt) "hw perfevents: " fmt +#include <linux/cpumask.h> #include <linux/kernel.h> #include <linux/platform_device.h> #include <linux/pm_runtime.h> @@ -229,6 +230,10 @@ 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. */ @@ -454,6 +459,17 @@ 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 +505,10 @@ 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); } @@ -496,6 +516,11 @@ static void armpmu_enable(struct pmu *pmu) static void armpmu_disable(struct pmu *pmu) { struct arm_pmu *armpmu = to_arm_pmu(pmu); + + /* For task-bound events we may be called on other CPUs */ + if (!cpumask_test_cpu(smp_processor_id(), &armpmu->supported_cpus)) + return; + armpmu->stop(armpmu); } diff --git a/arch/arm/kernel/perf_event_cpu.c b/arch/arm/kernel/perf_event_cpu.c index 2a9003ef6db3..9602d31aae03 100644 --- a/arch/arm/kernel/perf_event_cpu.c +++ b/arch/arm/kernel/perf_event_cpu.c @@ -179,11 +179,15 @@ static int cpu_pmu_request_irq(struct arm_pmu *cpu_pmu, irq_handler_t handler) 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 @@ -219,7 +223,8 @@ static int cpu_pmu_init(struct arm_pmu *cpu_pmu) /* Ensure the PMU has sane values out of reset. */ if (cpu_pmu->reset) - on_each_cpu(cpu_pmu->reset, cpu_pmu, 1); + 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)) @@ -334,12 +339,15 @@ static int of_pmu_irq_cfg(struct arm_pmu *pmu) } irqs[i] = cpu; + cpumask_set_cpu(cpu, &pmu->supported_cpus); } - if (i == pdev->num_resources) + if (i == pdev->num_resources) { pmu->irq_affinity = irqs; - else + } else { kfree(irqs); + cpumask_setall(&pmu->supported_cpus); + } return 0; } @@ -374,6 +382,7 @@ static int cpu_pmu_device_probe(struct platform_device *pdev) ret = init_fn(pmu); } else { ret = probe_current_pmu(pmu); + cpumask_setall(&pmu->supported_cpus); } if (ret) { |