Re: [PATCH v7 14/22] ACPI: platform_profile: Notify change events on register and unregister

["Ilpo Järvinen" <ilpo.jarvinen@linux.intel.com>]

On Tue, 19 Nov 2024, Mario Limonciello wrote:

> As multiple platform profile handlers may come and go, send a notification
> to userspace each time that a platform profile handler is registered or
> unregistered.
> 
> Reviewed-by: Armin Wolf <W_Armin@gmx.de>
> Tested-by: Mark Pearson <mpearson-lenovo@squebb.ca>
> Tested-by: Matthew Schwartz <matthew.schwartz@linux.dev>
> Reviewed-by: Mark Pearson <mpearson-lenovo@squebb.ca>
> Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
> ---
> v7:
>  * Add Armin's tag
> ---
>  drivers/acpi/platform_profile.c | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/drivers/acpi/platform_profile.c b/drivers/acpi/platform_profile.c
> index 1530e6096cd39..de0804305b02c 100644
> --- a/drivers/acpi/platform_profile.c
> +++ b/drivers/acpi/platform_profile.c
> @@ -363,6 +363,8 @@ int platform_profile_register(struct platform_profile_handler *pprof)
>  		goto cleanup_ida;
>  	}
>  
> +	sysfs_notify(acpi_kobj, NULL, "platform_profile");
> +
>  	cur_profile = pprof;
>  
>  	err = sysfs_update_group(acpi_kobj, &platform_profile_group);

Is the ordering problematic here, how long userspace has to wait for the 
update to become visible?

> @@ -393,6 +395,8 @@ int platform_profile_remove(struct platform_profile_handler *pprof)
>  	device_unregister(pprof->class_dev);
>  	ida_free(&platform_profile_ida, id);
>  
> +	sysfs_notify(acpi_kobj, NULL, "platform_profile");
> +
>  	sysfs_update_group(acpi_kobj, &platform_profile_group);


-- 
 i.