thermal: convert cpu_cooling to use an IDA

thermal cpu cooling does not use the ability to look up pointers by ID,
so convert it from using an IDR to the more space-efficient IDA.

The cooling_cpufreq_lock was being used to protect cpufreq_dev_count as
well as the IDR.  Rather than keep the mutex to protect a single integer,
I expanded the scope of cooling_list_lock to also cover cpufreq_dev_count.
We could also convert cpufreq_dev_count into an atomic.

Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
This commit is contained in:
Matthew Wilcox 2016-12-21 09:47:05 -08:00 committed by Zhang Rui
parent 7a6639dca6
commit ae60608962

View File

@ -26,6 +26,7 @@
#include <linux/thermal.h>
#include <linux/cpufreq.h>
#include <linux/err.h>
#include <linux/idr.h>
#include <linux/pm_opp.h>
#include <linux/slab.h>
#include <linux/cpu.h>
@ -104,50 +105,13 @@ struct cpufreq_cooling_device {
struct device *cpu_dev;
get_static_t plat_get_static_power;
};
static DEFINE_IDR(cpufreq_idr);
static DEFINE_MUTEX(cooling_cpufreq_lock);
static DEFINE_IDA(cpufreq_ida);
static unsigned int cpufreq_dev_count;
static DEFINE_MUTEX(cooling_list_lock);
static LIST_HEAD(cpufreq_dev_list);
/**
* get_idr - function to get a unique id.
* @idr: struct idr * handle used to create a id.
* @id: int * value generated by this function.
*
* This function will populate @id with an unique
* id, using the idr API.
*
* Return: 0 on success, an error code on failure.
*/
static int get_idr(struct idr *idr, int *id)
{
int ret;
mutex_lock(&cooling_cpufreq_lock);
ret = idr_alloc(idr, NULL, 0, 0, GFP_KERNEL);
mutex_unlock(&cooling_cpufreq_lock);
if (unlikely(ret < 0))
return ret;
*id = ret;
return 0;
}
/**
* release_idr - function to free the unique id.
* @idr: struct idr * handle used for creating the id.
* @id: int value representing the unique id.
*/
static void release_idr(struct idr *idr, int id)
{
mutex_lock(&cooling_cpufreq_lock);
idr_remove(idr, id);
mutex_unlock(&cooling_cpufreq_lock);
}
/* Below code defines functions to be used for cpufreq as cooling device */
/**
@ -874,11 +838,12 @@ __cpufreq_cooling_register(struct device_node *np,
cooling_ops = &cpufreq_cooling_ops;
}
ret = get_idr(&cpufreq_idr, &cpufreq_dev->id);
if (ret) {
ret = ida_simple_get(&cpufreq_ida, 0, 0, GFP_KERNEL);
if (ret < 0) {
cool_dev = ERR_PTR(ret);
goto free_power_table;
}
cpufreq_dev->id = ret;
/* Fill freq-table in descending order of frequencies */
for (i = 0, freq = -1; i <= cpufreq_dev->max_level; i++) {
@ -898,27 +863,24 @@ __cpufreq_cooling_register(struct device_node *np,
cool_dev = thermal_of_cooling_device_register(np, dev_name, cpufreq_dev,
cooling_ops);
if (IS_ERR(cool_dev))
goto remove_idr;
goto remove_ida;
cpufreq_dev->clipped_freq = cpufreq_dev->freq_table[0];
cpufreq_dev->cool_dev = cool_dev;
mutex_lock(&cooling_cpufreq_lock);
mutex_lock(&cooling_list_lock);
list_add(&cpufreq_dev->node, &cpufreq_dev_list);
mutex_unlock(&cooling_list_lock);
/* Register the notifier for first cpufreq cooling device */
if (!cpufreq_dev_count++)
cpufreq_register_notifier(&thermal_cpufreq_notifier_block,
CPUFREQ_POLICY_NOTIFIER);
mutex_unlock(&cooling_cpufreq_lock);
mutex_unlock(&cooling_list_lock);
goto put_policy;
remove_idr:
release_idr(&cpufreq_idr, cpufreq_dev->id);
remove_ida:
ida_simple_remove(&cpufreq_ida, cpufreq_dev->id);
free_power_table:
kfree(cpufreq_dev->dyn_power_table);
free_table:
@ -1059,20 +1021,17 @@ void cpufreq_cooling_unregister(struct thermal_cooling_device *cdev)
cpufreq_dev = cdev->devdata;
mutex_lock(&cooling_list_lock);
/* Unregister the notifier for the last cpufreq cooling device */
mutex_lock(&cooling_cpufreq_lock);
if (!--cpufreq_dev_count)
cpufreq_unregister_notifier(&thermal_cpufreq_notifier_block,
CPUFREQ_POLICY_NOTIFIER);
mutex_lock(&cooling_list_lock);
list_del(&cpufreq_dev->node);
mutex_unlock(&cooling_list_lock);
mutex_unlock(&cooling_cpufreq_lock);
thermal_cooling_device_unregister(cpufreq_dev->cool_dev);
release_idr(&cpufreq_idr, cpufreq_dev->id);
ida_simple_remove(&cpufreq_ida, cpufreq_dev->id);
kfree(cpufreq_dev->dyn_power_table);
kfree(cpufreq_dev->time_in_idle_timestamp);
kfree(cpufreq_dev->time_in_idle);