[deliverable/linux.git] / drivers / base / cpu.c

/*
 * drivers/base/cpu.c - basic CPU class support
 */

#include <linux/sysdev.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/cpu.h>
#include <linux/topology.h>
#include <linux/device.h>

#include "base.h"

struct sysdev_class cpu_sysdev_class = {
	set_kset_name("cpu"),
};
EXPORT_SYMBOL(cpu_sysdev_class);

static struct sys_device *cpu_sys_devices[NR_CPUS];

#ifdef CONFIG_HOTPLUG_CPU
int __attribute__((weak)) smp_prepare_cpu (int cpu)
{
	return 0;
}

static ssize_t show_online(struct sys_device *dev, char *buf)
{
	struct cpu *cpu = container_of(dev, struct cpu, sysdev);

	return sprintf(buf, "%u\n", !!cpu_online(cpu->sysdev.id));
}

static ssize_t store_online(struct sys_device *dev, const char *buf,
			    size_t count)
{
	struct cpu *cpu = container_of(dev, struct cpu, sysdev);
	ssize_t ret;

	switch (buf[0]) {
	case '0':
		ret = cpu_down(cpu->sysdev.id);
		if (!ret)
			kobject_uevent(&dev->kobj, KOBJ_OFFLINE);
		break;
	case '1':
		ret = smp_prepare_cpu(cpu->sysdev.id);
		if (!ret)
			ret = cpu_up(cpu->sysdev.id);
		if (!ret)
			kobject_uevent(&dev->kobj, KOBJ_ONLINE);
		break;
	default:
		ret = -EINVAL;
	}

	if (ret >= 0)
		ret = count;
	return ret;
}
static SYSDEV_ATTR(online, 0600, show_online, store_online);

static void __devinit register_cpu_control(struct cpu *cpu)
{
	sysdev_create_file(&cpu->sysdev, &attr_online);
}
void unregister_cpu(struct cpu *cpu, struct node *root)
{
	int logical_cpu = cpu->sysdev.id;

	if (root)
		sysfs_remove_link(&root->sysdev.kobj,
				  kobject_name(&cpu->sysdev.kobj));
	sysdev_remove_file(&cpu->sysdev, &attr_online);

	sysdev_unregister(&cpu->sysdev);
	cpu_sys_devices[logical_cpu] = NULL;
	return;
}
#else /* ... !CONFIG_HOTPLUG_CPU */
static inline void register_cpu_control(struct cpu *cpu)
{
}
#endif /* CONFIG_HOTPLUG_CPU */

/*
 * register_cpu - Setup a driverfs device for a CPU.
 * @cpu - Callers can set the cpu->no_control field to 1, to indicate not to
 *		  generate a control file in sysfs for this CPU.
 * @num - CPU number to use when creating the device.
 *
 * Initialize and register the CPU device.
 */
int __devinit register_cpu(struct cpu *cpu, int num, struct node *root)
{
	int error;

	cpu->node_id = cpu_to_node(num);
	cpu->sysdev.id = num;
	cpu->sysdev.cls = &cpu_sysdev_class;

	error = sysdev_register(&cpu->sysdev);
	if (!error && root)
		error = sysfs_create_link(&root->sysdev.kobj,
					  &cpu->sysdev.kobj,
					  kobject_name(&cpu->sysdev.kobj));
	if (!error && !cpu->no_control)
		register_cpu_control(cpu);
	if (!error)
		cpu_sys_devices[num] = &cpu->sysdev;
	return error;
}

struct sys_device *get_cpu_sysdev(int cpu)
{
	if (cpu < NR_CPUS)
		return cpu_sys_devices[cpu];
	else
		return NULL;
}
EXPORT_SYMBOL_GPL(get_cpu_sysdev);

int __init cpu_dev_init(void)
{
	return sysdev_class_register(&cpu_sysdev_class);
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* drivers/base/cpu.c - basic CPU class support
	3	*/
	4
	5	#include <linux/sysdev.h>
	6	#include <linux/module.h>
	7	#include <linux/init.h>
	8	#include <linux/cpu.h>
	9	#include <linux/topology.h>
	10	#include <linux/device.h>
	11
a1bdc7aa	12	#include "base.h"
1da177e4 LT	13
	14	struct sysdev_class cpu_sysdev_class = {
	15	set_kset_name("cpu"),
	16	};
	17	EXPORT_SYMBOL(cpu_sysdev_class);
	18
ad74557a AR	19	static struct sys_device *cpu_sys_devices[NR_CPUS];
ad74557a AR	20
1da177e4	21	#ifdef CONFIG_HOTPLUG_CPU
52a119fe AR	22	int __attribute__((weak)) smp_prepare_cpu (int cpu)
	23	{
	24	return 0;
	25	}
e1367daf	26
1da177e4 LT	27	static ssize_t show_online(struct sys_device dev, char buf)
	28	{
	29	struct cpu *cpu = container_of(dev, struct cpu, sysdev);
	30
	31	return sprintf(buf, "%u\n", !!cpu_online(cpu->sysdev.id));
	32	}
	33
	34	static ssize_t store_online(struct sys_device dev, const char buf,
	35	size_t count)
	36	{
	37	struct cpu *cpu = container_of(dev, struct cpu, sysdev);
	38	ssize_t ret;
	39
	40	switch (buf[0]) {
	41	case '0':
	42	ret = cpu_down(cpu->sysdev.id);
	43	if (!ret)
312c004d	44	kobject_uevent(&dev->kobj, KOBJ_OFFLINE);
1da177e4 LT	45	break;
1da177e4 LT	46	case '1':
e1367daf	47	ret = smp_prepare_cpu(cpu->sysdev.id);
52a119fe	48	if (!ret)
e1367daf	49	ret = cpu_up(cpu->sysdev.id);
fb69c390	50	if (!ret)
312c004d	51	kobject_uevent(&dev->kobj, KOBJ_ONLINE);
1da177e4 LT	52	break;
	53	default:
	54	ret = -EINVAL;
	55	}
	56
	57	if (ret >= 0)
	58	ret = count;
	59	return ret;
	60	}
	61	static SYSDEV_ATTR(online, 0600, show_online, store_online);
	62
	63	static void __devinit register_cpu_control(struct cpu *cpu)
	64	{
	65	sysdev_create_file(&cpu->sysdev, &attr_online);
	66	}
	67	void unregister_cpu(struct cpu cpu, struct node root)
	68	{
ad74557a	69	int logical_cpu = cpu->sysdev.id;
1da177e4 LT	70
	71	if (root)
	72	sysfs_remove_link(&root->sysdev.kobj,
	73	kobject_name(&cpu->sysdev.kobj));
	74	sysdev_remove_file(&cpu->sysdev, &attr_online);
	75
	76	sysdev_unregister(&cpu->sysdev);
ad74557a	77	cpu_sys_devices[logical_cpu] = NULL;
1da177e4 LT	78	return;
	79	}
	80	#else /* ... !CONFIG_HOTPLUG_CPU */
	81	static inline void register_cpu_control(struct cpu *cpu)
	82	{
	83	}
	84	#endif /* CONFIG_HOTPLUG_CPU */
	85
	86	/*
	87	* register_cpu - Setup a driverfs device for a CPU.
	88	* @cpu - Callers can set the cpu->no_control field to 1, to indicate not to
	89	* generate a control file in sysfs for this CPU.
	90	* @num - CPU number to use when creating the device.
	91	*
	92	* Initialize and register the CPU device.
	93	*/
	94	int __devinit register_cpu(struct cpu cpu, int num, struct node root)
	95	{
	96	int error;
	97
	98	cpu->node_id = cpu_to_node(num);
	99	cpu->sysdev.id = num;
	100	cpu->sysdev.cls = &cpu_sysdev_class;
	101
	102	error = sysdev_register(&cpu->sysdev);
	103	if (!error && root)
	104	error = sysfs_create_link(&root->sysdev.kobj,
	105	&cpu->sysdev.kobj,
	106	kobject_name(&cpu->sysdev.kobj));
	107	if (!error && !cpu->no_control)
	108	register_cpu_control(cpu);
ad74557a AR	109	if (!error)
ad74557a AR	110	cpu_sys_devices[num] = &cpu->sysdev;
1da177e4 LT	111	return error;
	112	}
	113
ad74557a AR	114	struct sys_device *get_cpu_sysdev(int cpu)
	115	{
	116	if (cpu < NR_CPUS)
	117	return cpu_sys_devices[cpu];
	118	else
	119	return NULL;
	120	}
	121	EXPORT_SYMBOL_GPL(get_cpu_sysdev);
1da177e4 LT	122
	123	int __init cpu_dev_init(void)
	124	{
	125	return sysdev_class_register(&cpu_sysdev_class);
	126	}