[PATCH 3/3] thermal/drivers/cpuidle_cooling: Use device name instead of auto-numbering

From: Daniel Lezcano
Date: Wed Mar 10 2021 - 06:47:36 EST


Currently the naming of a cooling device is just a cooling technique
followed by a number. When there are multiple cooling devices using
the same technique, it is impossible to clearly identify the related
device as this one is just a number.

For instance:

thermal-idle-0
thermal-idle-1
thermal-idle-2
thermal-idle-3
etc ...

The 'thermal' prefix is redundant with the subsystem namespace. This
patch removes the 'thermal prefix and changes the number by the device
name. So the naming above becomes:

idle-cpu0
idle-cpu1
idle-cpu2
idle-cpu3
etc ...

Signed-off-by: Daniel Lezcano <daniel.lezcano@xxxxxxxxxx>
---
drivers/thermal/cpuidle_cooling.c | 26 ++++++++++----------------
1 file changed, 10 insertions(+), 16 deletions(-)

diff --git a/drivers/thermal/cpuidle_cooling.c b/drivers/thermal/cpuidle_cooling.c
index 7ecab4b16b29..8bc0a9b46358 100644
--- a/drivers/thermal/cpuidle_cooling.c
+++ b/drivers/thermal/cpuidle_cooling.c
@@ -9,6 +9,7 @@

#include <linux/cpu_cooling.h>
#include <linux/cpuidle.h>
+#include <linux/device.h>
#include <linux/err.h>
#include <linux/idle_inject.h>
#include <linux/idr.h>
@@ -26,8 +27,6 @@ struct cpuidle_cooling_device {
unsigned long state;
};

-static DEFINE_IDA(cpuidle_ida);
-
/**
* cpuidle_cooling_runtime - Running time computation
* @idle_duration_us: CPU idle time to inject in microseconds
@@ -174,10 +173,11 @@ static int __cpuidle_cooling_register(struct device_node *np,
struct idle_inject_device *ii_dev;
struct cpuidle_cooling_device *idle_cdev;
struct thermal_cooling_device *cdev;
+ struct device *dev;
unsigned int idle_duration_us = TICK_USEC;
unsigned int latency_us = UINT_MAX;
- char dev_name[THERMAL_NAME_LENGTH];
- int id, ret;
+ char name[THERMAL_NAME_LENGTH];
+ int ret;

idle_cdev = kzalloc(sizeof(*idle_cdev), GFP_KERNEL);
if (!idle_cdev) {
@@ -185,16 +185,10 @@ static int __cpuidle_cooling_register(struct device_node *np,
goto out;
}

- id = ida_simple_get(&cpuidle_ida, 0, 0, GFP_KERNEL);
- if (id < 0) {
- ret = id;
- goto out_kfree;
- }
-
ii_dev = idle_inject_register(drv->cpumask);
if (!ii_dev) {
ret = -EINVAL;
- goto out_id;
+ goto out_kfree;
}

of_property_read_u32(np, "duration-us", &idle_duration_us);
@@ -205,9 +199,11 @@ static int __cpuidle_cooling_register(struct device_node *np,

idle_cdev->ii_dev = ii_dev;

- snprintf(dev_name, sizeof(dev_name), "thermal-idle-%d", id);
+ dev = get_cpu_device(cpumask_first(drv->cpumask));
+
+ snprintf(name, sizeof(name), "idle-%s", dev_name(dev));

- cdev = thermal_of_cooling_device_register(np, dev_name, idle_cdev,
+ cdev = thermal_of_cooling_device_register(np, name, idle_cdev,
&cpuidle_cooling_ops);
if (IS_ERR(cdev)) {
ret = PTR_ERR(cdev);
@@ -215,14 +211,12 @@ static int __cpuidle_cooling_register(struct device_node *np,
}

pr_debug("%s: Idle injection set with idle duration=%u, latency=%u\n",
- dev_name, idle_duration_us, latency_us);
+ name, idle_duration_us, latency_us);

return 0;

out_unregister:
idle_inject_unregister(ii_dev);
-out_id:
- ida_simple_remove(&cpuidle_ida, id);
out_kfree:
kfree(idle_cdev);
out:
--
2.17.1