ACPI: battery: Simplify battery hook locking

Move the conditional locking from __battery_hook_unregister()
into battery_hook_unregister() and rename the low-level function
to simplify the locking during battery hook removal.

Reviewed-by: Ilpo Järvinen <[email protected]>
Reviewed-by: Pali Rohár <[email protected]>
Signed-off-by: Armin Wolf <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Rafael J. Wysocki <[email protected]>

Author: Wer-Wolf

drivers/acpi/battery.c

@@ -703,28 +703,28 @@ static LIST_HEAD(acpi_battery_list);
 static LIST_HEAD(battery_hook_list);
 static DEFINE_MUTEX(hook_mutex);
 
-static void __battery_hook_unregister(struct acpi_battery_hook *hook, int lock)
+static void battery_hook_unregister_unlocked(struct acpi_battery_hook *hook)
 {
 	struct acpi_battery *battery;
+
 	/*
 	 * In order to remove a hook, we first need to
 	 * de-register all the batteries that are registered.
 	 */
-	if (lock)
-		mutex_lock(&hook_mutex);
 	list_for_each_entry(battery, &acpi_battery_list, list) {
 		if (!hook->remove_battery(battery->bat, hook))
 			power_supply_changed(battery->bat);
 	}
 	list_del(&hook->list);
-	if (lock)
-		mutex_unlock(&hook_mutex);
+
 	pr_info("extension unregistered: %s\n", hook->name);
 }
 
 void battery_hook_unregister(struct acpi_battery_hook *hook)
 {
-	__battery_hook_unregister(hook, 1);
+	mutex_lock(&hook_mutex);
+	battery_hook_unregister_unlocked(hook);
+	mutex_unlock(&hook_mutex);
 }
 EXPORT_SYMBOL_GPL(battery_hook_unregister);
 
@@ -750,7 +750,7 @@ void battery_hook_register(struct acpi_battery_hook *hook)
 			 * hooks.
 			 */
 			pr_err("extension failed to load: %s", hook->name);
-			__battery_hook_unregister(hook, 0);
+			battery_hook_unregister_unlocked(hook);
 			goto end;
 		}
 
@@ -804,7 +804,7 @@ static void battery_hook_add_battery(struct acpi_battery *battery)
 			 */
 			pr_err("error in extension, unloading: %s",
 					hook_node->name);
-			__battery_hook_unregister(hook_node, 0);
+			battery_hook_unregister_unlocked(hook_node);
 		}
 	}
 	mutex_unlock(&hook_mutex);
@@ -837,7 +837,7 @@ static void __exit battery_hook_exit(void)
 	 * need to remove the hooks.
 	 */
 	list_for_each_entry_safe(hook, ptr, &battery_hook_list, list) {
-		__battery_hook_unregister(hook, 1);
+		battery_hook_unregister(hook);
 	}
 	mutex_destroy(&hook_mutex);
 }