bus/arm-cci: Convert to hotplug statemachine (28c94843) · Commits · 戴 / test

drivers/bus/arm-cci.c

+23 −30

Original line number	Diff line number	Diff line
		@@ -144,12 +144,15 @@ struct cci_pmu {
		int num_cntrs;
		atomic_t active_events;
		struct mutex reserve_mutex;
		struct notifier_block cpu_nb;
		struct list_head entry;
		cpumask_t cpus;
		};

		#define to_cci_pmu(c) (container_of(c, struct cci_pmu, pmu))

		static DEFINE_MUTEX(cci_pmu_mutex);
		static LIST_HEAD(cci_pmu_list);

		enum cci_models {
		#ifdef CONFIG_ARM_CCI400_PMU
		CCI400_R0,
		@@ -1503,31 +1506,26 @@ static int cci_pmu_init(struct cci_pmu cci_pmu, struct platform_device pdev)
		return perf_pmu_register(&cci_pmu->pmu, name, -1);
		}

		static int cci_pmu_cpu_notifier(struct notifier_block *self,
		unsigned long action, void *hcpu)
		static int cci_pmu_offline_cpu(unsigned int cpu)
		{
		struct cci_pmu *cci_pmu = container_of(self,
		struct cci_pmu, cpu_nb);
		unsigned int cpu = (long)hcpu;
		struct cci_pmu *cci_pmu;
		unsigned int target;

		switch (action & ~CPU_TASKS_FROZEN) {
		case CPU_DOWN_PREPARE:
		mutex_lock(&cci_pmu_mutex);
		list_for_each_entry(cci_pmu, &cci_pmu_list, entry) {
		if (!cpumask_test_and_clear_cpu(cpu, &cci_pmu->cpus))
		break;
		continue;
		target = cpumask_any_but(cpu_online_mask, cpu);
		if (target >= nr_cpu_ids) // UP, last CPU
		break;
		if (target >= nr_cpu_ids)
		continue;
		/*
		* TODO: migrate context once core races on event->ctx have
		* been fixed.
		*/
		cpumask_set_cpu(target, &cci_pmu->cpus);
		default:
		break;
		}

		return NOTIFY_OK;
		mutex_unlock(&cci_pmu_mutex);
		return 0;
		}

		static struct cci_pmu_model cci_pmu_models[] = {
		@@ -1766,24 +1764,13 @@ static int cci_pmu_probe(struct platform_device *pdev)
		atomic_set(&cci_pmu->active_events, 0);
		cpumask_set_cpu(smp_processor_id(), &cci_pmu->cpus);

		cci_pmu->cpu_nb = (struct notifier_block) {
		.notifier_call = cci_pmu_cpu_notifier,
		/*
		* to migrate uncore events, our notifier should be executed
		* before perf core's notifier.
		*/
		.priority = CPU_PRI_PERF + 1,
		};

		ret = register_cpu_notifier(&cci_pmu->cpu_nb);
		ret = cci_pmu_init(cci_pmu, pdev);
		if (ret)
		return ret;

		ret = cci_pmu_init(cci_pmu, pdev);
		if (ret) {
		unregister_cpu_notifier(&cci_pmu->cpu_nb);
		return ret;
		}
		mutex_lock(&cci_pmu_mutex);
		list_add(&cci_pmu->entry, &cci_pmu_list);
		mutex_unlock(&cci_pmu_mutex);

		pr_info("ARM %s PMU driver probed", cci_pmu->model->name);
		return 0;
		@@ -1817,6 +1804,12 @@ static int __init cci_platform_init(void)
		{
		int ret;

		ret = cpuhp_setup_state_nocalls(CPUHP_AP_PERF_ARM_CCI_ONLINE,
		"AP_PERF_ARM_CCI_ONLINE", NULL,
		cci_pmu_offline_cpu);
		if (ret)
		return ret;

		ret = platform_driver_register(&cci_pmu_driver);
		if (ret)
		return ret;

include/linux/cpuhotplug.h

+1 −0

Original line number	Diff line number	Diff line
		@@ -45,6 +45,7 @@ enum cpuhp_state {
		CPUHP_AP_PERF_X86_CSTATE_ONLINE,
		CPUHP_AP_PERF_S390_CF_ONLINE,
		CPUHP_AP_PERF_S390_SF_ONLINE,
		CPUHP_AP_PERF_ARM_CCI_ONLINE,
		CPUHP_AP_NOTIFY_ONLINE,
		CPUHP_AP_ONLINE_DYN,
		CPUHP_AP_ONLINE_DYN_END = CPUHP_AP_ONLINE_DYN + 30,

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