C++ cpumask_set_cpu函数代码示例

static int db8500_cpufreq_cooling_probe(struct platform_device *pdev)
{
	struct thermal_cooling_device *cdev;
	struct cpumask mask_val;

	/* make sure cpufreq driver has been initialized */
	if (!cpufreq_frequency_get_table(0))
		return -EPROBE_DEFER;

	cpumask_set_cpu(0, &mask_val);
	cdev = cpufreq_cooling_register(&mask_val);

	if (IS_ERR(cdev)) {
		dev_err(&pdev->dev, "Failed to register cooling device\n");
		return PTR_ERR(cdev);
	}

	platform_set_drvdata(pdev, cdev);

	dev_info(&pdev->dev, "Cooling device registered: %s\n",	cdev->type);

	return 0;
}

/*
 * cpudl_find - find the best (later-dl) CPU in the system
 * @cp: the cpudl max-heap context
 * @p: the task
 * @later_mask: a mask to fill in with the selected CPUs (or NULL)
 *
 * Returns: int - best CPU (heap maximum if suitable)
 */
int cpudl_find(struct cpudl *cp, struct task_struct *p,
	       struct cpumask *later_mask)
{
	int best_cpu = -1;
	const struct sched_dl_entity *dl_se = &p->dl;

	if (later_mask && cpumask_and(later_mask, cp->free_cpus,
			&p->cpus_allowed) && cpumask_and(later_mask,
			later_mask, cpu_active_mask)) {
		best_cpu = cpumask_any(later_mask);
		goto out;
	} else if (cpumask_test_cpu(cpudl_maximum(cp), &p->cpus_allowed) &&
			dl_time_before(dl_se->deadline, cp->elements[0].dl)) {
		best_cpu = cpudl_maximum(cp);
		if (later_mask)
			cpumask_set_cpu(best_cpu, later_mask);
	}

out:
	WARN_ON(!cpu_present(best_cpu) && best_cpu != -1);

	return best_cpu;
}

/* Register with the in-kernel thermal management */
static int amlogic_register_thermal(struct amlogic_thermal_platform_data *pdata)
{
	int ret=0;
	struct cpumask mask_val;
	memset(&mask_val,0,sizeof(struct cpumask));
	cpumask_set_cpu(0, &mask_val);
	pdata->cpu_cool_dev= cpufreq_cooling_register(&mask_val);
	if (IS_ERR(pdata->cpu_cool_dev)) {
		pr_err("Failed to register cpufreq cooling device\n");
		ret = -EINVAL;
		goto err_unregister;
	}
	pdata->cpucore_cool_dev = cpucore_cooling_register();
	if (IS_ERR(pdata->cpucore_cool_dev)) {
		pr_err("Failed to register cpufreq cooling device\n");
		ret = -EINVAL;
		goto err_unregister;
	}

	pdata->therm_dev = thermal_zone_device_register(pdata->name,
			pdata->temp_trip_count, 7, pdata, &amlogic_dev_ops, NULL, 0,
			pdata->idle_interval);

	if (IS_ERR(pdata->therm_dev)) {
		pr_err("Failed to register thermal zone device\n");
		ret = -EINVAL;
		goto err_unregister;
	}

	pr_info("amlogic: Kernel Thermal management registered\n");

	return 0;

err_unregister:
	amlogic_unregister_thermal(pdata);
	return ret;
}

int disable_nonboot_cpus(void)
{
	int cpu, first_cpu, error = 0;

	cpu_maps_update_begin();
	first_cpu = cpumask_first(cpu_online_mask);
	/*
	 * We take down all of the non-boot CPUs in one shot to avoid races
	 * with the userspace trying to use the CPU hotplug at the same time
	 */
	cpumask_clear(frozen_cpus);

	pr_info("Disabling non-boot CPUs ...\n");
	for_each_online_cpu(cpu) {
		if (cpu == first_cpu)
			continue;
		trace_suspend_resume(TPS("CPU_OFF"), cpu, true);
		error = _cpu_down(cpu, 1);
		trace_suspend_resume(TPS("CPU_OFF"), cpu, false);
		if (!error)
			cpumask_set_cpu(cpu, frozen_cpus);
		else {
			pr_err("Error taking CPU%d down: %d\n", cpu, error);
			break;
		}
	}

	if (!error) {
		BUG_ON(num_online_cpus() > 1);
		/* Make sure the CPUs won't be enabled by someone else */
		cpu_hotplug_disabled = 1;
	} else {
		pr_err("Non-boot CPUs are not disabled\n");
	}
	cpu_maps_update_done();
	return error;
}

void __init prom_init(void)
{
	int *argv, *envp;		/* passed as 32 bit ptrs */
	struct psb_info *prom_infop;
	void *reset_vec;
#ifdef CONFIG_SMP
	int i;
#endif

	/* truncate to 32 bit and sign extend all args */
	argv = (int *)(long)(int)fw_arg1;
	envp = (int *)(long)(int)fw_arg2;
	prom_infop = (struct psb_info *)(long)(int)fw_arg3;

	nlm_prom_info = *prom_infop;
	nlm_init_node();

	/* Update reset entry point with CPU init code */
	reset_vec = (void *)CKSEG1ADDR(RESET_VEC_PHYS);
	memset(reset_vec, 0, RESET_VEC_SIZE);
	memcpy(reset_vec, (void *)nlm_reset_entry,
			(nlm_reset_entry_end - nlm_reset_entry));

	nlm_early_serial_setup();
	build_arcs_cmdline(argv);
	prom_add_memory();

#ifdef CONFIG_SMP
	for (i = 0; i < 32; i++)
		if (nlm_prom_info.online_cpu_map & (1 << i))
			cpumask_set_cpu(i, &nlm_cpumask);
	nlm_wakeup_secondary_cpus();
	register_smp_ops(&nlm_smp_ops);
#endif
	xlr_board_info_setup();
	xlr_percpu_fmn_init();
}

/**
 * percpu_ida_free - free a tag
 * @pool: pool @tag was allocated from
 * @tag: a tag previously allocated with percpu_ida_alloc()
 *
 * Safe to be called from interrupt context.
 */
void percpu_ida_free(struct percpu_ida *pool, unsigned tag)
{
	struct percpu_ida_cpu *tags;
	unsigned long flags;
	unsigned nr_free;

	BUG_ON(tag >= pool->nr_tags);

	tags = raw_cpu_ptr(pool->tag_cpu);

	spin_lock_irqsave(&tags->lock, flags);
	tags->freelist[tags->nr_free++] = tag;

	nr_free = tags->nr_free;

	if (nr_free == 1) {
		cpumask_set_cpu(smp_processor_id(),
				&pool->cpus_have_tags);
		wake_up(&pool->wait);
	}
	spin_unlock_irqrestore(&tags->lock, flags);

	if (nr_free == pool->percpu_max_size) {
		spin_lock_irqsave(&pool->lock, flags);
		spin_lock(&tags->lock);

		if (tags->nr_free == pool->percpu_max_size) {
			move_tags(pool->freelist, &pool->nr_free,
				  tags->freelist, &tags->nr_free,
				  pool->percpu_batch_size);

			wake_up(&pool->wait);
		}
		spin_unlock(&tags->lock);
		spin_unlock_irqrestore(&pool->lock, flags);
	}
}

void crash_ipi_callback(struct pt_regs *regs)
{
	static cpumask_t cpus_state_saved = CPU_MASK_NONE;

	int cpu = smp_processor_id();

	if (!cpu_online(cpu))
		return;

	hard_irq_disable();
	if (!cpumask_test_cpu(cpu, &cpus_state_saved)) {
		crash_save_cpu(regs, cpu);
		cpumask_set_cpu(cpu, &cpus_state_saved);
	}

	atomic_inc(&cpus_in_crash);
	smp_mb__after_atomic_inc();

	/*
	 * Starting the kdump boot.
	 * This barrier is needed to make sure that all CPUs are stopped.
	 */
	while (!time_to_dump)
		cpu_relax();

	if (ppc_md.kexec_cpu_down)
		ppc_md.kexec_cpu_down(1, 1);

#ifdef CONFIG_PPC64
	kexec_smp_wait();
#else
	for (;;);	/* FIXME */
#endif

	/* NOTREACHED */
}

void rq_attach_root(struct rq *rq, struct root_domain *rd)
{
	struct root_domain *old_rd = NULL;
	unsigned long flags;

	raw_spin_lock_irqsave(&rq->lock, flags);

	if (rq->rd) {
		old_rd = rq->rd;

		if (cpumask_test_cpu(rq->cpu, old_rd->online))
			set_rq_offline(rq);

		cpumask_clear_cpu(rq->cpu, old_rd->span);

		/*
		 * If we dont want to free the old_rd yet then
		 * set old_rd to NULL to skip the freeing later
		 * in this function:
		 */
		if (!atomic_dec_and_test(&old_rd->refcount))
			old_rd = NULL;
	}

	atomic_inc(&rd->refcount);
	rq->rd = rd;

	cpumask_set_cpu(rq->cpu, rd->span);
	if (cpumask_test_cpu(rq->cpu, cpu_active_mask))
		set_rq_online(rq);

	raw_spin_unlock_irqrestore(&rq->lock, flags);

	if (old_rd)
		call_rcu_sched(&old_rd->rcu, free_rootdomain);
}

/*
 * Take a map of online CPUs and the number of available interrupt vectors
 * and generate an output cpumask suitable for spreading MSI/MSI-X vectors
 * so that they are distributed as good as possible around the CPUs.  If
 * more vectors than CPUs are available we'll map one to each CPU,
 * otherwise we map one to the first sibling of each socket.
 *
 * If there are more vectors than CPUs we will still only have one bit
 * set per CPU, but interrupt code will keep on assigning the vectors from
 * the start of the bitmap until we run out of vectors.
 */
struct cpumask *irq_create_affinity_mask(unsigned int *nr_vecs)
{
	struct cpumask *affinity_mask;
	unsigned int max_vecs = *nr_vecs;

	if (max_vecs == 1)
		return NULL;

	affinity_mask = kzalloc(cpumask_size(), GFP_KERNEL);
	if (!affinity_mask) {
		*nr_vecs = 1;
		return NULL;
	}

	get_online_cpus();
	if (max_vecs >= num_online_cpus()) {
		cpumask_copy(affinity_mask, cpu_online_mask);
		*nr_vecs = num_online_cpus();
	} else {
		unsigned int vecs = 0, cpu;

		for_each_online_cpu(cpu) {
			if (cpu == get_first_sibling(cpu)) {
				cpumask_set_cpu(cpu, affinity_mask);
				vecs++;
			}

			if (--max_vecs == 0)
				break;
		}
		*nr_vecs = vecs;
	}
	put_online_cpus();

	return affinity_mask;
}

void noinline bench_outstanding_parallel_cpus(uint32_t loops, int nr_cpus,
					      int outstanding_pages)
{
	const char *desc = "parallel_cpus";
	struct time_bench_sync sync;
	struct time_bench_cpu *cpu_tasks;
	struct cpumask my_cpumask;
	int i;

	/* Allocate records for CPUs */
	cpu_tasks = kzalloc(sizeof(*cpu_tasks) * nr_cpus, GFP_KERNEL);

	/* Reduce number of CPUs to run on */
	cpumask_clear(&my_cpumask);
	for (i = 0; i < nr_cpus ; i++) {
		cpumask_set_cpu(i, &my_cpumask);
	}
	pr_info("Limit to %d parallel CPUs\n", nr_cpus);
	time_bench_run_concurrent(loops, outstanding_pages, NULL,
				  &my_cpumask, &sync, cpu_tasks,
				  time_alloc_pages_outstanding);
	time_bench_print_stats_cpumask(desc, cpu_tasks, &my_cpumask);
	kfree(cpu_tasks);
}

static int __init hyperv_prepare_irq_remapping(void)
{
	struct fwnode_handle *fn;
	int i;

	if (!hypervisor_is_type(X86_HYPER_MS_HYPERV) ||
	    !x2apic_supported())
		return -ENODEV;

	fn = irq_domain_alloc_named_id_fwnode("HYPERV-IR", 0);
	if (!fn)
		return -ENOMEM;

	ioapic_ir_domain =
		irq_domain_create_hierarchy(arch_get_ir_parent_domain(),
				0, IOAPIC_REMAPPING_ENTRY, fn,
				&hyperv_ir_domain_ops, NULL);

	irq_domain_free_fwnode(fn);

	/*
	 * Hyper-V doesn't provide irq remapping function for
	 * IO-APIC and so IO-APIC only accepts 8-bit APIC ID.
	 * Cpu's APIC ID is read from ACPI MADT table and APIC IDs
	 * in the MADT table on Hyper-v are sorted monotonic increasingly.
	 * APIC ID reflects cpu topology. There maybe some APIC ID
	 * gaps when cpu number in a socket is not power of two. Prepare
	 * max cpu affinity for IOAPIC irqs. Scan cpu 0-255 and set cpu
	 * into ioapic_max_cpumask if its APIC ID is less than 256.
	 */
	for (i = min_t(unsigned int, num_possible_cpus() - 1, 255); i >= 0; i--)
		if (cpu_physical_id(i) < 256)
			cpumask_set_cpu(i, &ioapic_max_cpumask);

	return 0;
}

static int __init bl_idle_driver_init(struct cpuidle_driver *drv, int cpu_id)
{
	struct cpuinfo_arm *cpu_info;
	struct cpumask *cpumask;
	unsigned long cpuid;
	int cpu;

	cpumask = kzalloc(cpumask_size(), GFP_KERNEL);
	if (!cpumask)
		return -ENOMEM;

	for_each_possible_cpu(cpu) {
		cpu_info = &per_cpu(cpu_data, cpu);
		cpuid = is_smp() ? cpu_info->cpuid : read_cpuid_id();

		/* read cpu id part number */
		if ((cpuid & 0xFFF0) == cpu_id)
			cpumask_set_cpu(cpu, cpumask);
	}

	drv->cpumask = cpumask;

	return 0;
}

/* Return a mask of the cpus whose caches currently own these pages. */
static void homecache_mask(struct page *page, int pages,
			   struct cpumask *home_mask)
{
	int i;
	cpumask_clear(home_mask);
	for (i = 0; i < pages; ++i) {
		int home = page_home(&page[i]);
		if (home == PAGE_HOME_IMMUTABLE ||
		    home == PAGE_HOME_INCOHERENT) {
			cpumask_copy(home_mask, cpu_possible_mask);
			return;
		}
#if CHIP_HAS_CBOX_HOME_MAP()
		if (home == PAGE_HOME_HASH) {
			cpumask_or(home_mask, home_mask, &hash_for_home_map);
			continue;
		}
#endif
		if (home == PAGE_HOME_UNCACHED)
			continue;
		BUG_ON(home < 0 || home >= NR_CPUS);
		cpumask_set_cpu(home, home_mask);
	}
}

static void update_siblings_masks(unsigned int cpuid)
{
	struct cpu_topology *cpu_topo, *cpuid_topo = &cpu_topology[cpuid];
	int cpu;

	if (cpuid_topo->cluster_id == -1) {
		/*
		 * DT does not contain topology information for this cpu
		 * reset it to default behaviour
		 */
		pr_debug("CPU%u: No topology information configured\n", cpuid);
		cpuid_topo->core_id = 0;
		cpumask_set_cpu(cpuid, &cpuid_topo->core_sibling);
		cpumask_set_cpu(cpuid, &cpuid_topo->thread_sibling);
		return;
	}

	/* update core and thread sibling masks */
	for_each_possible_cpu(cpu) {
		cpu_topo = &cpu_topology[cpu];

		if (cpuid_topo->cluster_id != cpu_topo->cluster_id)
			continue;

		cpumask_set_cpu(cpuid, &cpu_topo->core_sibling);
		if (cpu != cpuid)
			cpumask_set_cpu(cpu, &cpuid_topo->core_sibling);

		if (cpuid_topo->core_id != cpu_topo->core_id)
			continue;

		cpumask_set_cpu(cpuid, &cpu_topo->thread_sibling);
		if (cpu != cpuid)
			cpumask_set_cpu(cpu, &cpuid_topo->thread_sibling);
	}
}

static int tegra_cpuidle_register(unsigned int cpu)
{
	struct cpuidle_driver *drv;
	struct cpuidle_state *state;

	drv = &per_cpu(cpuidle_drv, cpu);
	drv->name = driver_name;
	drv->owner = owner;
	drv->cpumask = &per_cpu(idle_mask, cpu);
	cpumask_set_cpu(cpu, drv->cpumask);
	drv->state_count = 0;

	state = &drv->states[CPUIDLE_STATE_CLKGATING];
	snprintf(state->name, CPUIDLE_NAME_LEN, "clock-gated");
	snprintf(state->desc, CPUIDLE_DESC_LEN, "CPU clock gated");
	state->exit_latency = 10;
	state->target_residency = 10;
	state->power_usage = 600;
	state->flags = CPUIDLE_FLAG_TIME_VALID;
	state->enter = tegra_idle_enter_clock_gating;
#ifdef CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED
	drv->safe_state_index = 0;
#endif
	drv->state_count++;

#ifdef CONFIG_PM_SLEEP
	state = &drv->states[CPUIDLE_STATE_POWERGATING];
	snprintf(state->name, CPUIDLE_NAME_LEN, "powered-down");
	snprintf(state->desc, CPUIDLE_DESC_LEN, "CPU power gated");
	state->exit_latency = tegra_cpu_power_good_time();
	state->target_residency = tegra_cpu_power_off_time() +
		tegra_cpu_power_good_time();
	if (state->target_residency < tegra_pd_min_residency)
		state->target_residency = tegra_pd_min_residency;
	state->power_usage = 100;
	state->flags = CPUIDLE_FLAG_TIME_VALID;
	state->enter = tegra_idle_enter_pd;
	drv->state_count++;

	if (cpu == 0) {
		state = &drv->states[CPUIDLE_STATE_MC_CLK_STOP];
		snprintf(state->name, CPUIDLE_NAME_LEN, "mc-clock");
		snprintf(state->desc, CPUIDLE_DESC_LEN, "MC clock stop");
		state->exit_latency = tegra_cpu_power_good_time() +
			DRAM_SELF_REFRESH_EXIT_LATENCY;
		state->target_residency = tegra_cpu_power_off_time() +
			tegra_cpu_power_good_time() + DRAM_SELF_REFRESH_EXIT_LATENCY;
		if (state->target_residency < tegra_mc_clk_stop_min_residency())
			state->target_residency =
					tegra_mc_clk_stop_min_residency();
		state->power_usage = 0;
		state->flags = CPUIDLE_FLAG_TIME_VALID;
		state->enter = tegra_idle_enter_pd;
		state->disabled = true;
		drv->state_count++;
	}
#endif

	if (cpuidle_register(drv, NULL)) {
		pr_err("CPU%u: failed to register driver\n", cpu);
		return -EIO;
	}

	on_each_cpu_mask(drv->cpumask, tegra_cpuidle_setup_bctimer,
				(void *)CLOCK_EVT_NOTIFY_BROADCAST_ON, 1);

	return 0;
}