Re: [PATCH v2 1/3] ACPI: battery: Simplify battery hook locking
From: Ilpo Järvinen
Date: Mon Sep 23 2024 - 09:35:56 EST
On Sun, 22 Sep 2024, Armin Wolf wrote:
> 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.
>
> Signed-off-by: Armin Wolf <W_Armin@xxxxxx>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx>
--
i.
> ---
> 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 da3a879d638a..10e9136897a7 100644
> --- a/drivers/acpi/battery.c
> +++ b/drivers/acpi/battery.c
> @@ -706,28 +706,28 @@ 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);
>
> @@ -753,7 +753,7 @@ 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;
> }
>
> @@ -807,7 +807,7 @@ 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);
> @@ -840,7 +840,7 @@ 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
>