linux/drivers/thermal/thermal_core.h
Rafael J. Wysocki 790930f442 thermal: core: Introduce thermal_cooling_device_update()
Introduce a core thermal API function, thermal_cooling_device_update(),
for updating the max_state value for a cooling device and rearranging
its statistics in sysfs after a possible change of its ->get_max_state()
callback return value.

That callback is now invoked only once, during cooling device
registration, to populate the max_state field in the cooling device
object, so if its return value changes, it needs to be invoked again
and the new return value needs to be stored as max_state.  Moreover,
the statistics presented in sysfs need to be rearranged in general,
because there may not be enough room in them to store data for all
of the possible states (in the case when max_state grows).

The new function takes care of that (and some other minor things
related to it), but some extra locking and lockdep annotations are
added in several places too to protect against crashes in the cases
when the statistics are not present or when a stale max_state value
might be used by sysfs attributes.

Note that the actual user of the new function will be added separately.

Link: https://lore.kernel.org/linux-pm/53ec1f06f61c984100868926f282647e57ecfb2d.camel@intel.com/
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Zhang Rui <rui.zhang@intel.com>
Reviewed-by: Zhang Rui <rui.zhang@intel.com>
2023-03-22 15:20:38 +01:00

151 lines
5.1 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/*
* thermal_core.h
*
* Copyright (C) 2012 Intel Corp
* Author: Durgadoss R <durgadoss.r@intel.com>
*/
#ifndef __THERMAL_CORE_H__
#define __THERMAL_CORE_H__
#include <linux/device.h>
#include <linux/thermal.h>
#include "thermal_netlink.h"
/* Default Thermal Governor */
#if defined(CONFIG_THERMAL_DEFAULT_GOV_STEP_WISE)
#define DEFAULT_THERMAL_GOVERNOR "step_wise"
#elif defined(CONFIG_THERMAL_DEFAULT_GOV_FAIR_SHARE)
#define DEFAULT_THERMAL_GOVERNOR "fair_share"
#elif defined(CONFIG_THERMAL_DEFAULT_GOV_USER_SPACE)
#define DEFAULT_THERMAL_GOVERNOR "user_space"
#elif defined(CONFIG_THERMAL_DEFAULT_GOV_POWER_ALLOCATOR)
#define DEFAULT_THERMAL_GOVERNOR "power_allocator"
#endif
/* Initial state of a cooling device during binding */
#define THERMAL_NO_TARGET -1UL
/* Init section thermal table */
extern struct thermal_governor *__governor_thermal_table[];
extern struct thermal_governor *__governor_thermal_table_end[];
#define THERMAL_TABLE_ENTRY(table, name) \
static typeof(name) *__thermal_table_entry_##name \
__used __section("__" #table "_thermal_table") = &name
#define THERMAL_GOVERNOR_DECLARE(name) THERMAL_TABLE_ENTRY(governor, name)
#define for_each_governor_table(__governor) \
for (__governor = __governor_thermal_table; \
__governor < __governor_thermal_table_end; \
__governor++)
int for_each_thermal_zone(int (*cb)(struct thermal_zone_device *, void *),
void *);
int for_each_thermal_cooling_device(int (*cb)(struct thermal_cooling_device *,
void *), void *);
int for_each_thermal_governor(int (*cb)(struct thermal_governor *, void *),
void *thermal_governor);
int __for_each_thermal_trip(struct thermal_zone_device *,
int (*cb)(struct thermal_trip *, void *),
void *);
struct thermal_zone_device *thermal_zone_get_by_id(int id);
struct thermal_attr {
struct device_attribute attr;
char name[THERMAL_NAME_LENGTH];
};
static inline bool cdev_is_power_actor(struct thermal_cooling_device *cdev)
{
return cdev->ops->get_requested_power && cdev->ops->state2power &&
cdev->ops->power2state;
}
void thermal_cdev_update(struct thermal_cooling_device *);
void __thermal_cdev_update(struct thermal_cooling_device *cdev);
int get_tz_trend(struct thermal_zone_device *tz, int trip);
struct thermal_instance *
get_thermal_instance(struct thermal_zone_device *tz,
struct thermal_cooling_device *cdev,
int trip);
/*
* This structure is used to describe the behavior of
* a certain cooling device on a certain trip point
* in a certain thermal zone
*/
struct thermal_instance {
int id;
char name[THERMAL_NAME_LENGTH];
struct thermal_zone_device *tz;
struct thermal_cooling_device *cdev;
int trip;
bool initialized;
unsigned long upper; /* Highest cooling state for this trip point */
unsigned long lower; /* Lowest cooling state for this trip point */
unsigned long target; /* expected cooling state */
char attr_name[THERMAL_NAME_LENGTH];
struct device_attribute attr;
char weight_attr_name[THERMAL_NAME_LENGTH];
struct device_attribute weight_attr;
struct list_head tz_node; /* node in tz->thermal_instances */
struct list_head cdev_node; /* node in cdev->thermal_instances */
unsigned int weight; /* The weight of the cooling device */
bool upper_no_limit;
};
#define to_thermal_zone(_dev) \
container_of(_dev, struct thermal_zone_device, device)
#define to_cooling_device(_dev) \
container_of(_dev, struct thermal_cooling_device, device)
int thermal_register_governor(struct thermal_governor *);
void thermal_unregister_governor(struct thermal_governor *);
int thermal_zone_device_set_policy(struct thermal_zone_device *, char *);
int thermal_build_list_of_policies(char *buf);
void __thermal_zone_device_update(struct thermal_zone_device *tz,
enum thermal_notify_event event);
/* Helpers */
void __thermal_zone_set_trips(struct thermal_zone_device *tz);
int __thermal_zone_get_trip(struct thermal_zone_device *tz, int trip_id,
struct thermal_trip *trip);
int __thermal_zone_get_temp(struct thermal_zone_device *tz, int *temp);
/* sysfs I/F */
int thermal_zone_create_device_groups(struct thermal_zone_device *, int);
void thermal_zone_destroy_device_groups(struct thermal_zone_device *);
void thermal_cooling_device_setup_sysfs(struct thermal_cooling_device *);
void thermal_cooling_device_destroy_sysfs(struct thermal_cooling_device *cdev);
void thermal_cooling_device_stats_reinit(struct thermal_cooling_device *cdev);
/* used only at binding time */
ssize_t trip_point_show(struct device *, struct device_attribute *, char *);
ssize_t weight_show(struct device *, struct device_attribute *, char *);
ssize_t weight_store(struct device *, struct device_attribute *, const char *,
size_t);
#ifdef CONFIG_THERMAL_STATISTICS
void thermal_cooling_device_stats_update(struct thermal_cooling_device *cdev,
unsigned long new_state);
#else
static inline void
thermal_cooling_device_stats_update(struct thermal_cooling_device *cdev,
unsigned long new_state) {}
#endif /* CONFIG_THERMAL_STATISTICS */
/* device tree support */
int thermal_zone_device_is_enabled(struct thermal_zone_device *tz);
#endif /* __THERMAL_CORE_H__ */