From: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Straight forward conversion w/o bells and whistles. Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Signed-off-by: Anna-Maria Gleixner <anna-maria@xxxxxxxxxxxxx> Reviewed-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx> Acked-by: Mark Rutland <mark.rutland@xxxxxxx> Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Cc: Mark Rutland <mark.rutland@xxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: Will Deacon <will.deacon@xxxxxxx> Cc: rt@xxxxxxxxxxxxx [bigeasy@xxxx: use arm_pmu_list to handle multiple PMUs in the system] Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx> --- v2…v3: >80 chars line for per_err, added Mark's Acked-by v1…v2: use arm_pmu_list drivers/perf/arm_pmu.c | 59 +++++++++++++++++++++++++++----------------- include/linux/cpuhotplug.h | 1 + include/linux/perf/arm_pmu.h | 2 +- 3 files changed, 39 insertions(+), 23 deletions(-) diff --git a/drivers/perf/arm_pmu.c b/drivers/perf/arm_pmu.c index 140436a046c0..f6ab4f7f75bf 100644 --- a/drivers/perf/arm_pmu.c +++ b/drivers/perf/arm_pmu.c @@ -685,30 +685,29 @@ static int cpu_pmu_request_irq(struct arm_pmu *cpu_pmu, irq_handler_t handler) return 0; } +static DEFINE_MUTEX(arm_pmu_mutex); +static LIST_HEAD(arm_pmu_list); + /* * 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) +static int arm_perf_starting_cpu(unsigned int cpu) { - int cpu = (unsigned long)hcpu; - struct arm_pmu *pmu = container_of(b, struct arm_pmu, hotplug_nb); + struct arm_pmu *pmu; - if ((action & ~CPU_TASKS_FROZEN) != CPU_STARTING) - return NOTIFY_DONE; + mutex_lock(&arm_pmu_mutex); + list_for_each_entry(pmu, &arm_pmu_list, entry) { - if (!cpumask_test_cpu(cpu, &pmu->supported_cpus)) - return NOTIFY_DONE; - - if (pmu->reset) - pmu->reset(pmu); - else - return NOTIFY_DONE; - - return NOTIFY_OK; + if (!cpumask_test_cpu(cpu, &pmu->supported_cpus)) + continue; + if (pmu->reset) + pmu->reset(pmu); + } + mutex_unlock(&arm_pmu_mutex); + return 0; } #ifdef CONFIG_CPU_PM @@ -819,10 +818,9 @@ static int cpu_pmu_init(struct arm_pmu *cpu_pmu) 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; + mutex_lock(&arm_pmu_mutex); + list_add_tail(&cpu_pmu->entry, &arm_pmu_list); + mutex_unlock(&arm_pmu_mutex); err = cpu_pm_pmu_register(cpu_pmu); if (err) @@ -858,8 +856,9 @@ static int cpu_pmu_init(struct arm_pmu *cpu_pmu) return 0; out_unregister: - unregister_cpu_notifier(&cpu_pmu->hotplug_nb); -out_hw_events: + mutex_lock(&arm_pmu_mutex); + list_del(&cpu_pmu->entry); + mutex_unlock(&arm_pmu_mutex); free_percpu(cpu_hw_events); return err; } @@ -867,7 +866,9 @@ static int cpu_pmu_init(struct arm_pmu *cpu_pmu) static void cpu_pmu_destroy(struct arm_pmu *cpu_pmu) { cpu_pm_pmu_unregister(cpu_pmu); - unregister_cpu_notifier(&cpu_pmu->hotplug_nb); + mutex_lock(&arm_pmu_mutex); + list_del(&cpu_pmu->entry); + mutex_unlock(&arm_pmu_mutex); free_percpu(cpu_pmu->hw_events); } @@ -1044,3 +1045,17 @@ int arm_pmu_device_probe(struct platform_device *pdev, kfree(pmu); return ret; } + +static int arm_pmu_hp_init(void) +{ + int ret; + + ret = cpuhp_setup_state_nocalls(CPUHP_AP_PERF_ARM_STARTING, + "AP_PERF_ARM_STARTING", + arm_perf_starting_cpu, NULL); + if (ret) + pr_err("CPU hotplug notifier for ARM PMU could not be registered: %d\n", + ret); + return ret; +} +subsys_initcall(arm_pmu_hp_init); diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h index 4c63cb30aee6..a5b6a6526af8 100644 --- a/include/linux/cpuhotplug.h +++ b/include/linux/cpuhotplug.h @@ -35,6 +35,7 @@ enum cpuhp_state { CPUHP_AP_PERF_X86_CSTATE_STARTING, CPUHP_AP_PERF_XTENSA_STARTING, CPUHP_AP_ARM_VFP_STARTING, + CPUHP_AP_PERF_ARM_STARTING, CPUHP_AP_NOTIFY_STARTING, CPUHP_AP_ONLINE, CPUHP_TEARDOWN_CPU, diff --git a/include/linux/perf/arm_pmu.h b/include/linux/perf/arm_pmu.h index d28ac05c7f92..e18843809eec 100644 --- a/include/linux/perf/arm_pmu.h +++ b/include/linux/perf/arm_pmu.h @@ -109,7 +109,7 @@ struct arm_pmu { DECLARE_BITMAP(pmceid_bitmap, ARMV8_PMUV3_MAX_COMMON_EVENTS); struct platform_device *plat_device; struct pmu_hw_events __percpu *hw_events; - struct notifier_block hotplug_nb; + struct list_head entry; struct notifier_block cpu_pm_nb; }; -- 2.8.1 -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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