linux_kernel/drivers/cpufreq/cpufreq_governor_attr_set.c
Thomas Gleixner d2912cb15b treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500
Based on 2 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation #

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 4122 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-19 17:09:55 +02:00

82 lines
2.1 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Abstract code for CPUFreq governor tunable sysfs attributes.
*
* Copyright (C) 2016, Intel Corporation
* Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
*/
#include "cpufreq_governor.h"
static inline struct gov_attr_set *to_gov_attr_set(struct kobject *kobj)
{
return container_of(kobj, struct gov_attr_set, kobj);
}
static inline struct governor_attr *to_gov_attr(struct attribute *attr)
{
return container_of(attr, struct governor_attr, attr);
}
static ssize_t governor_show(struct kobject *kobj, struct attribute *attr,
char *buf)
{
struct governor_attr *gattr = to_gov_attr(attr);
return gattr->show(to_gov_attr_set(kobj), buf);
}
static ssize_t governor_store(struct kobject *kobj, struct attribute *attr,
const char *buf, size_t count)
{
struct gov_attr_set *attr_set = to_gov_attr_set(kobj);
struct governor_attr *gattr = to_gov_attr(attr);
int ret;
mutex_lock(&attr_set->update_lock);
ret = attr_set->usage_count ? gattr->store(attr_set, buf, count) : -EBUSY;
mutex_unlock(&attr_set->update_lock);
return ret;
}
const struct sysfs_ops governor_sysfs_ops = {
.show = governor_show,
.store = governor_store,
};
EXPORT_SYMBOL_GPL(governor_sysfs_ops);
void gov_attr_set_init(struct gov_attr_set *attr_set, struct list_head *list_node)
{
INIT_LIST_HEAD(&attr_set->policy_list);
mutex_init(&attr_set->update_lock);
attr_set->usage_count = 1;
list_add(list_node, &attr_set->policy_list);
}
EXPORT_SYMBOL_GPL(gov_attr_set_init);
void gov_attr_set_get(struct gov_attr_set *attr_set, struct list_head *list_node)
{
mutex_lock(&attr_set->update_lock);
attr_set->usage_count++;
list_add(list_node, &attr_set->policy_list);
mutex_unlock(&attr_set->update_lock);
}
EXPORT_SYMBOL_GPL(gov_attr_set_get);
unsigned int gov_attr_set_put(struct gov_attr_set *attr_set, struct list_head *list_node)
{
unsigned int count;
mutex_lock(&attr_set->update_lock);
list_del(list_node);
count = --attr_set->usage_count;
mutex_unlock(&attr_set->update_lock);
if (count)
return count;
kobject_put(&attr_set->kobj);
mutex_destroy(&attr_set->update_lock);
return 0;
}
EXPORT_SYMBOL_GPL(gov_attr_set_put);