Commit 728ce22b authored by Daniel Lezcano's avatar Daniel Lezcano Committed by Rafael J. Wysocki
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cpuidle: Make cpuidle's sysfs directory dynamically allocated 



The cpuidle sysfs code is designed to have a single instance of per
CPU cpuidle directory.  It is not possible to remove the sysfs entry
and create it again.  This is not a problem with the current code but
future changes will add CPU hotplug support to enable/disable the
device, so it will need to remove the sysfs entry like other
subsystems do.  That won't be possible without this change, because
the kobj is a static object which can't be reused for
kobj_init_and_add().

Add cpuidle_device_kobj to be allocated dynamically when
adding/removing a sysfs entry which is consistent with the other
cpuidle's sysfs entries.

An added benefit is that the sysfs code is now more self-contained
and the includes needed for sysfs can be moved from cpuidle.h
directly into sysfs.c so as to reduce the total number of headers
dragged along with cpuidle.h.

[rjw: Changelog]
Signed-off-by: default avatarDaniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
parent f89ae89e

drivers/cpuidle/sysfs.c

+48 −15
Original line number Diff line number Diff line
@@ -11,8 +11,10 @@ 
#include <linux/sysfs.h>

#include <linux/slab.h>

#include <linux/cpu.h>

#include <linux/completion.h>

#include <linux/capability.h>

#include <linux/device.h>

#include <linux/kobject.h>



#include "cpuidle.h"
@@ -167,14 +169,27 @@ struct cpuidle_attr { 
#define define_one_rw(_name, show, store) \

	static struct cpuidle_attr attr_##_name = __ATTR(_name, 0644, show, store)



#define kobj_to_cpuidledev(k) container_of(k, struct cpuidle_device, kobj)

#define attr_to_cpuidleattr(a) container_of(a, struct cpuidle_attr, attr)



struct cpuidle_device_kobj {

	struct cpuidle_device *dev;

	struct completion kobj_unregister;

	struct kobject kobj;

};



static inline struct cpuidle_device *to_cpuidle_device(struct kobject *kobj)

{

	struct cpuidle_device_kobj *kdev =

		container_of(kobj, struct cpuidle_device_kobj, kobj);



	return kdev->dev;

}



static ssize_t cpuidle_show(struct kobject *kobj, struct attribute *attr,

			    char *buf)

{

	int ret = -EIO;

	struct cpuidle_device *dev = kobj_to_cpuidledev(kobj);

	struct cpuidle_device *dev = to_cpuidle_device(kobj);

	struct cpuidle_attr *cattr = attr_to_cpuidleattr(attr);



	if (cattr->show) {
@@ -189,7 +204,7 @@ static ssize_t cpuidle_store(struct kobject *kobj, struct attribute *attr, 
			     const char *buf, size_t count)

{

	int ret = -EIO;

	struct cpuidle_device *dev = kobj_to_cpuidledev(kobj);

	struct cpuidle_device *dev = to_cpuidle_device(kobj);

	struct cpuidle_attr *cattr = attr_to_cpuidleattr(attr);



	if (cattr->store) {
@@ -207,9 +222,10 @@ static const struct sysfs_ops cpuidle_sysfs_ops = { 


static void cpuidle_sysfs_release(struct kobject *kobj)

{

	struct cpuidle_device *dev = kobj_to_cpuidledev(kobj);

	struct cpuidle_device_kobj *kdev =

		container_of(kobj, struct cpuidle_device_kobj, kobj);



	complete(&dev->kobj_unregister);

	complete(&kdev->kobj_unregister);

}



static struct kobj_type ktype_cpuidle = {
@@ -377,6 +393,7 @@ static int cpuidle_add_state_sysfs(struct cpuidle_device *device) 
{

	int i, ret = -ENOMEM;

	struct cpuidle_state_kobj *kobj;

	struct cpuidle_device_kobj *kdev = device->kobj_dev;

	struct cpuidle_driver *drv = cpuidle_get_cpu_driver(device);



	/* state statistics */
@@ -389,7 +406,7 @@ static int cpuidle_add_state_sysfs(struct cpuidle_device *device) 
		init_completion(&kobj->kobj_unregister);



		ret = kobject_init_and_add(&kobj->kobj, &ktype_state_cpuidle,

					   &device->kobj, "state%d", i);

					   &kdev->kobj, "state%d", i);

		if (ret) {

			kfree(kobj);

			goto error_state;
@@ -506,6 +523,7 @@ static struct kobj_type ktype_driver_cpuidle = { 
static int cpuidle_add_driver_sysfs(struct cpuidle_device *dev)

{

	struct cpuidle_driver_kobj *kdrv;

	struct cpuidle_device_kobj *kdev = dev->kobj_dev;

	struct cpuidle_driver *drv = cpuidle_get_cpu_driver(dev);

	int ret;
@@ -517,7 +535,7 @@ static int cpuidle_add_driver_sysfs(struct cpuidle_device *dev) 
	init_completion(&kdrv->kobj_unregister);



	ret = kobject_init_and_add(&kdrv->kobj, &ktype_driver_cpuidle,

				   &dev->kobj, "driver");

				   &kdev->kobj, "driver");

	if (ret) {

		kfree(kdrv);

		return ret;
@@ -586,24 +604,39 @@ void cpuidle_remove_device_sysfs(struct cpuidle_device *device) 
 */

int cpuidle_add_sysfs(struct cpuidle_device *dev)

{

	struct cpuidle_device_kobj *kdev;

	struct device *cpu_dev = get_cpu_device((unsigned long)dev->cpu);

	int error;



	init_completion(&dev->kobj_unregister);

	kdev = kzalloc(sizeof(*kdev), GFP_KERNEL);

	if (!kdev)

		return -ENOMEM;

	kdev->dev = dev;

	dev->kobj_dev = kdev;



	init_completion(&kdev->kobj_unregister);



	error = kobject_init_and_add(&dev->kobj, &ktype_cpuidle, &cpu_dev->kobj,

	error = kobject_init_and_add(&kdev->kobj, &ktype_cpuidle, &cpu_dev->kobj,

				   "cpuidle");

	if (!error)

		kobject_uevent(&dev->kobj, KOBJ_ADD);

	if (error) {

		kfree(kdev);

		return error;

	}



	kobject_uevent(&kdev->kobj, KOBJ_ADD);



	return 0;

}



/**

 * cpuidle_remove_sysfs - deletes a sysfs instance on the target device

 * @dev: the target device

 */

void cpuidle_remove_sysfs(struct cpuidle_device *dev)

{

	kobject_put(&dev->kobj);

	wait_for_completion(&dev->kobj_unregister);

	struct cpuidle_device_kobj *kdev = dev->kobj_dev;



	kobject_put(&kdev->kobj);

	wait_for_completion(&kdev->kobj_unregister);

	kfree(kdev);

}

include/linux/cpuidle.h

+3 −4
Original line number Diff line number Diff line
@@ -13,8 +13,6 @@ 


#include <linux/percpu.h>

#include <linux/list.h>

#include <linux/kobject.h>

#include <linux/completion.h>

#include <linux/hrtimer.h>



#define CPUIDLE_STATE_MAX	10
@@ -61,6 +59,8 @@ struct cpuidle_state { 


#define CPUIDLE_DRIVER_FLAGS_MASK (0xFFFF0000)



struct cpuidle_device_kobj;



struct cpuidle_device {

	unsigned int		registered:1;

	unsigned int		enabled:1;
@@ -71,9 +71,8 @@ struct cpuidle_device { 
	struct cpuidle_state_usage	states_usage[CPUIDLE_STATE_MAX];

	struct cpuidle_state_kobj *kobjs[CPUIDLE_STATE_MAX];

	struct cpuidle_driver_kobj *kobj_driver;

	struct cpuidle_device_kobj *kobj_dev;

	struct list_head 	device_list;

	struct kobject		kobj;

	struct completion	kobj_unregister;



#ifdef CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED

	int			safe_state_index;

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