[PATCH v2 11/11] thermal: core: Manage thermal_governor_lock using a mutex guard

Rafael J. Wysocki
2024-10-10T22:22:33Z

From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Switch over the thermal core to using a mutex guard for
thermal_governor_lock management.

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
---

This is a resend of

https://lore.kernel.org/linux-pm/863177860.0ifERbkFSE@rjwysocki.net/

---
drivers/thermal/thermal_core.c | 40 +++++++++++++---------------------------
1 file changed, 13 insertions(+), 27 deletions(-)

Index: linux-pm/drivers/thermal/thermal_core.c
===================================================================
--- linux-pm.orig/drivers/thermal/thermal_core.c
+++ linux-pm/drivers/thermal/thermal_core.c
@@ -124,7 +124,7 @@ int thermal_register_governor(struct the
if (!governor)
return -EINVAL;

- mutex_lock(&thermal_governor_lock);
+ guard(mutex)(&thermal_governor_lock);

err = -EBUSY;
if (!__find_governor(governor->name)) {
@@ -163,8 +163,6 @@ int thermal_register_governor(struct the
}
}

- mutex_unlock(&thermal_governor_lock);
-
return err;
}

@@ -175,10 +173,10 @@ void thermal_unregister_governor(struct
if (!governor)
return;

- mutex_lock(&thermal_governor_lock);
+ guard(mutex)(&thermal_governor_lock);

if (!__find_governor(governor->name))
- goto exit;
+ return;

list_del(&governor->governor_list);

@@ -189,9 +187,6 @@ void thermal_unregister_governor(struct
THERMAL_NAME_LENGTH))
thermal_set_governor(pos, NULL);
}
-
-exit:
- mutex_unlock(&thermal_governor_lock);
}

int thermal_zone_device_set_policy(struct thermal_zone_device *tz,
@@ -200,16 +195,13 @@ int thermal_zone_device_set_policy(struc
struct thermal_governor *gov;
int ret = -EINVAL;

- mutex_lock(&thermal_governor_lock);
-
+ guard(mutex)(&thermal_governor_lock);
guard(thermal_zone)(tz);

gov = __find_governor(strim(policy));
if (gov)
ret = thermal_set_governor(tz, gov);

- mutex_unlock(&thermal_governor_lock);
-
thermal_notify_tz_gov_change(tz, policy);

return ret;
@@ -220,15 +212,13 @@ int thermal_build_list_of_policies(char
struct thermal_governor *pos;
ssize_t count = 0;

- mutex_lock(&thermal_governor_lock);
+ guard(mutex)(&thermal_governor_lock);

list_for_each_entry(pos, &thermal_governor_list, governor_list) {
count += sysfs_emit_at(buf, count, "%s ", pos->name);
}
count += sysfs_emit_at(buf, count, "\n");

- mutex_unlock(&thermal_governor_lock);
-
return count;
}

@@ -668,17 +658,18 @@ int for_each_thermal_governor(int (*cb)(
void *data)
{
struct thermal_governor *gov;
- int ret = 0;

- mutex_lock(&thermal_governor_lock);
+ guard(mutex)(&thermal_governor_lock);
+
list_for_each_entry(gov, &thermal_governor_list, governor_list) {
+ int ret;
+
ret = cb(gov, data);
if (ret)
- break;
+ return ret;
}
- mutex_unlock(&thermal_governor_lock);

- return ret;
+ return 0;
}

int for_each_thermal_cooling_device(int (*cb)(struct thermal_cooling_device *,
@@ -1346,20 +1337,15 @@ EXPORT_SYMBOL_GPL(thermal_zone_get_crit_
static int thermal_zone_init_governor(struct thermal_zone_device *tz)
{
struct thermal_governor *governor;
- int ret;

- mutex_lock(&thermal_governor_lock);
+ guard(mutex)(&thermal_governor_lock);

if (tz->tzp)
governor = __find_governor(tz->tzp->governor_name);
else
governor = def_governor;

- ret = thermal_set_governor(tz, governor);
-
- mutex_unlock(&thermal_governor_lock);
-
- return ret;
+ return thermal_set_governor(tz, governor);
}

static void thermal_zone_init_complete(struct thermal_zone_device *tz)