Re: [PATCH 1/3 v2] thermal: core: Add some new helper functions to free resources

[walter harms <wharms@bfs.de>]

Am 08.08.2017 16:39, schrieb Christophe JAILLET:
> In order to easily free resources allocated by
> 'thermal_zone_create_device_groups()' we need 2 new helper functions.
> 
> The first one undoes 'thermal_zone_create_device_groups()'.
> The 2nd one undoes 'create_trip_attrs()', which is a function called by
> 'thermal_zone_create_device_groups()'.
> 
> Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
> ---
> These functions will be used in patch 2/3 in order to simplify
> 'thermal_release()'
> I've tried to implement it as close a possible as the way the resources have
> been allocated.
> However, in 'thermal_release()', the code is simplier without some
> additionnal 'if'.
> No sure if we should prefer consistancy with allocation or simplicity of code.
> ---
>  drivers/thermal/thermal_core.h  |  1 +
>  drivers/thermal/thermal_sysfs.c | 29 +++++++++++++++++++++++++++++
>  2 files changed, 30 insertions(+)
> 
> diff --git a/drivers/thermal/thermal_core.h b/drivers/thermal/thermal_core.h
> index 2412b3759e16..27e3b1df7360 100644
> --- a/drivers/thermal/thermal_core.h
> +++ b/drivers/thermal/thermal_core.h
> @@ -71,6 +71,7 @@ int thermal_build_list_of_policies(char *buf);
>  
>  /* sysfs I/F */
>  int thermal_zone_create_device_groups(struct thermal_zone_device *, int);
> +void thermal_zone_destroy_device_groups(struct thermal_zone_device *);
>  void thermal_cooling_device_setup_sysfs(struct thermal_cooling_device *);
>  /* used only at binding time */
>  ssize_t
> diff --git a/drivers/thermal/thermal_sysfs.c b/drivers/thermal/thermal_sysfs.c
> index a694de907a26..eb95d64b9446 100644
> --- a/drivers/thermal/thermal_sysfs.c
> +++ b/drivers/thermal/thermal_sysfs.c
> @@ -605,6 +605,24 @@ static int create_trip_attrs(struct thermal_zone_device *tz, int mask)
>  	return 0;
>  }
>  
> +/**
> + * destroy_trip_attrs() - create attributes for trip points
> + * @tz:		the thermal zone device
> + *
> + * helper function to free resources alocated by create_trip_attrs()
> + */
> +static void destroy_trip_attrs(struct thermal_zone_device *tz)
> +{
> +	if (!tz)
> +		return;
> +
> +	kfree(tz->trip_type_attrs);
> +	kfree(tz->trip_temp_attrs);
> +	if (tz->ops->get_trip_hyst)
> +		kfree(tz->trip_hyst_attrs);
> +	kfree(tz->trips_attribute_group.attrs);
> +}
> +
>  int thermal_zone_create_device_groups(struct thermal_zone_device *tz,
>  				      int mask)
>  {
> @@ -637,6 +655,17 @@ int thermal_zone_create_device_groups(struct thermal_zone_device *tz,
>  	return 0;
>  }
>  
> +void thermal_zone_destroy_device_groups(struct thermal_zone_device *tz)
> +{
> +	if (!tz)
> +		return;
> +
> +	if (tz->trips)
> +		destroy_trip_attrs(tz);

why the check for tz->trips ?
destroy_trip_attrs does not access tz->trips->

re,
 wh

> +
> +	kfree(tz->device.groups);
> +}
> +
>  /* sys I/F for cooling device */
>  static ssize_t
>  thermal_cooling_device_type_show(struct device *dev,