[PATCH RESEND v3 1/3] ACPI: battery: Simplify battery hook locking

From: Armin Wolf
Date: Tue Oct 01 2024 - 17:29:27 EST


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 <ilpo.jarvinen@xxxxxxxxxxxxxxx>
Reviewed-by: Rafael J. Wysocki <rafael@xxxxxxxxxx>
Reviewed-by: Pali Rohár <pali@xxxxxxxxxx>
Signed-off-by: Armin Wolf <W_Armin@xxxxxx>
---
drivers/acpi/battery.c | 18 +++++++++---------
1 file changed, 9 insertions(+), 9 deletions(-)

diff --git a/drivers/acpi/battery.c b/drivers/acpi/battery.c
index f4599261cfc3..dda59ee5a11e 100644
--- a/drivers/acpi/battery.c
+++ b/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);
}
--
2.39.5