305 lines
6.9 KiB
C

/*
* Copyright (c) 2012 NVIDIA CORPORATION. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License.
*
* This program is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
*/
#include <linux/kernel.h>
#include <linux/sysfs.h>
#include <linux/slab.h>
#include <linux/cpu.h>
#include <linux/cpuquiet.h>
#include "cpuquiet.h"
struct cpuquiet_dev {
unsigned int cpu;
struct kobject kobj;
};
static struct kobject *cpuquiet_global_kobject;
static struct cpuquiet_dev *cpuquiet_cpu_devices[CONFIG_NR_CPUS];
static ssize_t show_current_governor(struct cpuquiet_attribute *cattr,
char *buf)
{
ssize_t ret;
mutex_lock(&cpuquiet_lock);
if (cpuquiet_curr_governor)
ret = sprintf(buf, "%s\n", cpuquiet_curr_governor->name);
else
ret = sprintf(buf, "none\n");
mutex_unlock(&cpuquiet_lock);
return ret;
}
static ssize_t store_current_governor(struct cpuquiet_attribute *cattr,
const char *buf, size_t count)
{
char name[CPUQUIET_NAME_LEN];
struct cpuquiet_governor *gov;
int len = count, ret = -EINVAL;
if (!len || len >= sizeof(name))
return -EINVAL;
memcpy(name, buf, count);
name[len] = '\0';
if (name[len - 1] == '\n')
name[--len] = '\0';
mutex_lock(&cpuquiet_lock);
gov = cpuquiet_find_governor(name);
if (gov)
ret = cpuquiet_switch_governor(gov);
mutex_unlock(&cpuquiet_lock);
if (ret)
return ret;
else
return count;
}
static ssize_t show_available_governors(struct cpuquiet_attribute *cattr,
char *buf)
{
ssize_t ret = 0, len;
struct cpuquiet_governor *gov;
mutex_lock(&cpuquiet_lock);
if (!list_empty(&cpuquiet_governors)) {
list_for_each_entry(gov, &cpuquiet_governors, governor_list) {
len = sprintf(buf, "%s ", gov->name);
buf += len;
ret += len;
}
buf--;
*buf = '\n';
} else
ret = sprintf(buf, "none\n");
mutex_unlock(&cpuquiet_lock);
return ret;
}
CPQ_ATTRIBUTE(current_governor, 0644, show_current_governor,
store_current_governor);
CPQ_ATTRIBUTE(available_governors, 0444, show_available_governors, NULL);
static struct attribute *cpuquiet_default_attrs[] = {
&current_governor_attr.attr,
&available_governors_attr.attr,
NULL,
};
static ssize_t cpuquiet_sysfs_show(struct kobject *kobj,
struct attribute *attr, char *buf)
{
struct cpuquiet_attribute *cattr =
container_of(attr, struct cpuquiet_attribute, attr);
return cattr->show(cattr, buf);
}
static ssize_t cpuquiet_sysfs_store(struct kobject *kobj,
struct attribute *attr, const char *buf, size_t count)
{
struct cpuquiet_attribute *cattr =
container_of(attr, struct cpuquiet_attribute, attr);
if (cattr->store)
return cattr->store(cattr, buf, count);
return -EINVAL;
}
const struct sysfs_ops cpuquiet_sysfs_ops = {
.show = cpuquiet_sysfs_show,
.store = cpuquiet_sysfs_store,
};
static struct kobj_type ktype_cpuquiet = {
.sysfs_ops = &cpuquiet_sysfs_ops,
.default_attrs = cpuquiet_default_attrs,
};
static ssize_t show_active(unsigned int cpu, char *buf)
{
return sprintf(buf, "%u\n", cpu_online(cpu));
}
static ssize_t store_active(unsigned int cpu, const char *value, size_t count)
{
unsigned int active;
int ret;
if (!cpuquiet_curr_governor->store_active)
return -EINVAL;
ret = sscanf(value, "%u", &active);
if (ret != 1)
return -EINVAL;
cpuquiet_curr_governor->store_active(cpu, active);
return count;
}
CPQ_CPU_ATTRIBUTE(active, 0644, show_active, store_active);
static struct attribute *cpuquiet_cpu_default_attrs[] = {
&active_attr.attr,
NULL,
};
static ssize_t cpuquiet_cpu_sysfs_show(struct kobject *kobj,
struct attribute *attr, char *buf)
{
struct cpuquiet_cpu_attribute *cattr =
container_of(attr, struct cpuquiet_cpu_attribute, attr);
struct cpuquiet_dev *dev =
container_of(kobj, struct cpuquiet_dev, kobj);
return cattr->show(dev->cpu, buf);
}
static ssize_t cpuquiet_cpu_sysfs_store(struct kobject *kobj,
struct attribute *attr, const char *buf, size_t count)
{
struct cpuquiet_cpu_attribute *cattr =
container_of(attr, struct cpuquiet_cpu_attribute, attr);
struct cpuquiet_dev *dev =
container_of(kobj, struct cpuquiet_dev, kobj);
if (cattr->store)
return cattr->store(dev->cpu, buf, count);
return -EINVAL;
}
static const struct sysfs_ops cpuquiet_cpu_sysfs_ops = {
.show = cpuquiet_cpu_sysfs_show,
.store = cpuquiet_cpu_sysfs_store,
};
static struct kobj_type ktype_cpuquiet_cpu = {
.sysfs_ops = &cpuquiet_cpu_sysfs_ops,
.default_attrs = cpuquiet_cpu_default_attrs,
};
int cpuquiet_add_dev(struct device *device, unsigned int cpu)
{
struct cpuquiet_dev *dev;
int err;
dev = kzalloc(sizeof(*dev), GFP_KERNEL);
if (!dev)
return -ENOMEM;
device = get_cpu_device(cpu);
dev_info(device, "cpuquiet_add_dev\n");
cpuquiet_cpu_devices[cpu] = dev;
dev->cpu = cpu;
err = kobject_init_and_add(&dev->kobj, &ktype_cpuquiet_cpu,
&device->kobj, "cpuquiet");
if (err) {
kfree(dev);
return err;
}
kobject_uevent(&dev->kobj, KOBJ_ADD);
return 0;
}
void cpuquiet_remove_dev(unsigned int cpu)
{
if (cpuquiet_cpu_devices[cpu])
kobject_put(&cpuquiet_cpu_devices[cpu]->kobj);
}
int cpuquiet_sysfs_init(void)
{
struct device *dev = cpu_subsys.dev_root;
int err;
cpuquiet_global_kobject = kzalloc(sizeof(*cpuquiet_global_kobject),
GFP_KERNEL);
if (!cpuquiet_global_kobject)
return -ENOMEM;
err = kobject_init_and_add(cpuquiet_global_kobject,
&ktype_cpuquiet, &dev->kobj, "cpuquiet");
if (err) {
kfree(cpuquiet_global_kobject);
return err;
}
kobject_uevent(cpuquiet_global_kobject, KOBJ_ADD);
return 0;
}
void cpuquiet_sysfs_exit(void)
{
kobject_put(cpuquiet_global_kobject);
}
int cpuquiet_register_attrs(struct attribute_group *attrs)
{
return sysfs_create_group(cpuquiet_global_kobject, attrs);
}
EXPORT_SYMBOL(cpuquiet_register_attrs);
void cpuquiet_unregister_attrs(struct attribute_group *attrs)
{
sysfs_remove_group(cpuquiet_global_kobject, attrs);
}
EXPORT_SYMBOL(cpuquiet_unregister_attrs);
int cpuquiet_register_cpu_attrs(struct attribute_group *attrs)
{
int cpu, ret = 0;
for_each_possible_cpu(cpu) {
if (cpuquiet_cpu_devices[cpu]) {
ret = sysfs_create_group(
&cpuquiet_cpu_devices[cpu]->kobj,
attrs);
if (ret) {
cpuquiet_unregister_cpu_attrs(attrs);
return ret;
}
}
}
return ret;
}
EXPORT_SYMBOL(cpuquiet_register_cpu_attrs);
void cpuquiet_unregister_cpu_attrs(struct attribute_group *attrs)
{
int cpu;
for_each_possible_cpu(cpu) {
if (cpuquiet_cpu_devices[cpu])
sysfs_remove_group(&cpuquiet_cpu_devices[cpu]->kobj,
attrs);
}
}
EXPORT_SYMBOL(cpuquiet_unregister_cpu_attrs);