[PATCH 3/5] thermal: cpu cooling: convert ID allocation to IDA

[Zhang Rui <rui.zhang@intel.com>]

thermal cpu cooling currently uses IDRs to allocate IDs, but it only needs
to know whether IDs are in use or not; the ID to pointer functionality
of the IDR is unused. That means it can use the more space-efficient IDA.

Signed-off-by: Zhang Rui <rui.zhang@intel.com>
---
 drivers/thermal/cpu_cooling.c | 50 ++++++-------------------------------------
 1 file changed, 7 insertions(+), 43 deletions(-)

diff --git a/drivers/thermal/cpu_cooling.c b/drivers/thermal/cpu_cooling.c
index 9ce0e9e..6ade44d 100644
--- a/drivers/thermal/cpu_cooling.c
+++ b/drivers/thermal/cpu_cooling.c
@@ -32,7 +32,7 @@
 #include <linux/cpu_cooling.h>
 
 #include <trace/events/thermal.h>
-
+#include "thermal_core.h"
 /*
  * Cooling state <-> CPUFreq frequency
  *
@@ -104,7 +104,7 @@ struct cpufreq_cooling_device {
 	struct device *cpu_dev;
 	get_static_t plat_get_static_power;
 };
-static DEFINE_IDR(cpufreq_idr);
+static DEFINE_IDA(cpufreq_ida);
 static DEFINE_MUTEX(cooling_cpufreq_lock);
 
 static unsigned int cpufreq_dev_count;
@@ -112,42 +112,6 @@ 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 */
 
 /**
@@ -874,7 +838,7 @@ __cpufreq_cooling_register(struct device_node *np,
 		cooling_ops = &cpufreq_cooling_ops;
 	}
 
-	ret = get_idr(&cpufreq_idr, &cpufreq_dev->id);
+	ret = get_ida(&cpufreq_ida, &cooling_cpufreq_lock, &cpufreq_dev->id);
 	if (ret) {
 		cool_dev = ERR_PTR(ret);
 		goto free_power_table;
@@ -898,7 +862,7 @@ __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;
@@ -917,8 +881,8 @@ __cpufreq_cooling_register(struct device_node *np,
 
 	goto put_policy;
 
-remove_idr:
-	release_idr(&cpufreq_idr, cpufreq_dev->id);
+remove_ida:
+	release_ida(&cpufreq_ida, &cooling_cpufreq_lock, cpufreq_dev->id);
 free_power_table:
 	kfree(cpufreq_dev->dyn_power_table);
 free_table:
@@ -1072,7 +1036,7 @@ void cpufreq_cooling_unregister(struct thermal_cooling_device *cdev)
 	mutex_unlock(&cooling_cpufreq_lock);
 
 	thermal_cooling_device_unregister(cpufreq_dev->cool_dev);
-	release_idr(&cpufreq_idr, cpufreq_dev->id);
+	release_ida(&cpufreq_ida, &cooling_cpufreq_lock, cpufreq_dev->id);
 	kfree(cpufreq_dev->dyn_power_table);
 	kfree(cpufreq_dev->time_in_idle_timestamp);
 	kfree(cpufreq_dev->time_in_idle);
-- 
2.7.4