Re: [PATCH v2] thermal: consistently use int for temperatures

[Punit Agrawal <punit.agrawal@arm.com>]

Hi Sascha,

Sascha Hauer <s.hauer@pengutronix.de> writes:

> The thermal code uses int, long and unsigned long for temperatures
> in different places.
>
> Using an unsigned type limits the thermal framework to positive
> temperatures without need. Also several drivers currently will report
> temperatures near UINT_MAX for temperatures below 0°C. This will probably
> immediately shut the machine down due to overtemperature if started below
> 0°C.
>
> 'long' is 64bit on several architectures. This is not needed since INT_MAX °mC
> is above the melting point of all known materials.
>
> Consistently use a plain 'int' for temperatures throughout the thermal code and
> the drivers. This only changes the places in the drivers where the temperature
> is passed around as pointer, when drivers internally use another type this is
> not changed.
>
> Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
> Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
> Reviewed-by: Jean Delvare <jdelvare@suse.de>
> Reviewed-by: Lukasz Majewski <l.majewski@samsung.com>
> Reviewed-by: Darren Hart <dvhart@linux.intel.com>
> Reviewed-by: Heiko Stuebner <heiko@sntech.de>
> Reviewed-by: Peter Feuerer <peter@piie.net>
> Cc: Punit Agrawal <punit.agrawal@arm.com>

The changes below look good.

For the power_allocator governor and corresponding trace events,

Reviewed-by: Punit Agrawal <punit.agrawal@arm.com>

Thanks

> Cc: Zhang Rui <rui.zhang@intel.com>
> Cc: Eduardo Valentin <edubezval@gmail.com>
> Cc: linux-pm@vger.kernel.org
> Cc: linux-kernel@vger.kernel.org
> Cc: Jean Delvare <jdelvare@suse.de>
> Cc: Peter Feuerer <peter@piie.net>
> Cc: Heiko Stuebner <heiko@sntech.de>
> Cc: Lukasz Majewski <l.majewski@samsung.com>
> Cc: Stephen Warren <swarren@wwwdotorg.org>
> Cc: Thierry Reding <thierry.reding@gmail.com>
> Cc: linux-acpi@vger.kernel.org
> Cc: platform-driver-x86@vger.kernel.org
> Cc: linux-arm-kernel@lists.infradead.org
> Cc: linux-omap@vger.kernel.org
> Cc: linux-samsung-soc@vger.kernel.org
> Cc: Guenter Roeck <linux@roeck-us.net>
> Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
> Cc: Maxime Ripard <maxime.ripard@free-electrons.com>
> Cc: Darren Hart <dvhart@infradead.org>
> Cc: lm-sensors@lm-sensors.org
> ---
>
> changes since v1:
> - Add missing pieces for power_allocator driver 
>
>  drivers/acpi/thermal.c                             | 12 +++++-----
>  drivers/hwmon/lm75.c                               |  2 +-
>  drivers/hwmon/ntc_thermistor.c                     |  2 +-
>  drivers/hwmon/tmp102.c                             |  2 +-
>  drivers/input/touchscreen/sun4i-ts.c               |  8 +++----
>  drivers/platform/x86/acerhdf.c                     |  9 ++++----
>  drivers/platform/x86/intel_mid_thermal.c           |  9 ++++----
>  drivers/power/power_supply_core.c                  |  2 +-
>  drivers/thermal/armada_thermal.c                   |  2 +-
>  drivers/thermal/db8500_thermal.c                   |  7 +++---
>  drivers/thermal/dove_thermal.c                     |  2 +-
>  drivers/thermal/fair_share.c                       |  2 +-
>  drivers/thermal/gov_bang_bang.c                    |  5 ++--
>  drivers/thermal/hisi_thermal.c                     |  4 ++--
>  drivers/thermal/imx_thermal.c                      | 27 +++++++++++-----------
>  drivers/thermal/int340x_thermal/int3400_thermal.c  |  2 +-
>  .../thermal/int340x_thermal/int340x_thermal_zone.c | 10 ++++----
>  .../thermal/int340x_thermal/int340x_thermal_zone.h |  8 +++----
>  .../int340x_thermal/processor_thermal_device.c     |  4 ++--
>  drivers/thermal/intel_quark_dts_thermal.c          | 13 +++++------
>  drivers/thermal/intel_soc_dts_iosf.c               |  8 +++----
>  drivers/thermal/kirkwood_thermal.c                 |  2 +-
>  drivers/thermal/of-thermal.c                       | 14 +++++------
>  drivers/thermal/power_allocator.c                  | 16 ++++++-------
>  drivers/thermal/qcom-spmi-temp-alarm.c             |  2 +-
>  drivers/thermal/rcar_thermal.c                     |  7 +++---
>  drivers/thermal/rockchip_thermal.c                 | 10 ++++----
>  drivers/thermal/samsung/exynos_tmu.c               | 23 +++++++++---------
>  drivers/thermal/spear_thermal.c                    |  2 +-
>  drivers/thermal/st/st_thermal.c                    |  5 ++--
>  drivers/thermal/step_wise.c                        |  4 ++--
>  drivers/thermal/tegra_soctherm.c                   |  4 ++--
>  drivers/thermal/thermal_core.c                     | 26 ++++++++++-----------
>  drivers/thermal/thermal_hwmon.c                    | 10 ++++----
>  drivers/thermal/ti-soc-thermal/ti-thermal-common.c | 10 ++++----
>  drivers/thermal/x86_pkg_temp_thermal.c             | 10 ++++----
>  include/linux/thermal.h                            | 26 +++++++++------------
>  include/trace/events/thermal_power_allocator.h     |  6 ++---
>  38 files changed, 151 insertions(+), 166 deletions(-)
>

[...]

> diff --git a/drivers/thermal/power_allocator.c b/drivers/thermal/power_allocator.c
> index 4672250..045aea59 100644
> --- a/drivers/thermal/power_allocator.c
> +++ b/drivers/thermal/power_allocator.c
> @@ -92,8 +92,8 @@ struct power_allocator_params {
>   * Return: The power budget for the next period.
>   */
>  static u32 pid_controller(struct thermal_zone_device *tz,
> -			  unsigned long current_temp,
> -			  unsigned long control_temp,
> +			  int current_temp,
> +			  int control_temp,
>  			  u32 max_allocatable_power)
>  {
>  	s64 p, i, d, power_range;
> @@ -102,7 +102,7 @@ static u32 pid_controller(struct thermal_zone_device *tz,
>  
>  	max_power_frac = int_to_frac(max_allocatable_power);
>  
> -	err = ((s32)control_temp - (s32)current_temp);
> +	err = control_temp - current_temp;
>  	err = int_to_frac(err);
>  
>  	/* Calculate the proportional term */
> @@ -223,8 +223,8 @@ static void divvy_up_power(u32 *req_power, u32 *max_power, int num_actors,
>  }
>  
>  static int allocate_power(struct thermal_zone_device *tz,
> -			  unsigned long current_temp,
> -			  unsigned long control_temp)
> +			  int current_temp,
> +			  int control_temp)
>  {
>  	struct thermal_instance *instance;
>  	struct power_allocator_params *params = tz->governor_data;
> @@ -326,7 +326,7 @@ static int allocate_power(struct thermal_zone_device *tz,
>  				      granted_power, total_granted_power,
>  				      num_actors, power_range,
>  				      max_allocatable_power, current_temp,
> -				      (s32)control_temp - (s32)current_temp);
> +				      control_temp - current_temp);
>  
>  	devm_kfree(&tz->device, req_power);
>  unlock:
> @@ -411,7 +411,7 @@ static int power_allocator_bind(struct thermal_zone_device *tz)
>  {
>  	int ret;
>  	struct power_allocator_params *params;
> -	unsigned long switch_on_temp, control_temp;
> +	int switch_on_temp, control_temp;
>  	u32 temperature_threshold;
>  
>  	if (!tz->tzp || !tz->tzp->sustainable_power) {
> @@ -476,7 +476,7 @@ static void power_allocator_unbind(struct thermal_zone_device *tz)
>  static int power_allocator_throttle(struct thermal_zone_device *tz, int trip)
>  {
>  	int ret;
> -	unsigned long switch_on_temp, control_temp, current_temp;
> +	int switch_on_temp, control_temp, current_temp;
>  	struct power_allocator_params *params = tz->governor_data;
>  
>  	/*

[...]

> diff --git a/include/trace/events/thermal_power_allocator.h b/include/trace/events/thermal_power_allocator.h
> index 12e1321..5afae8f 100644
> --- a/include/trace/events/thermal_power_allocator.h
> +++ b/include/trace/events/thermal_power_allocator.h
> @@ -11,7 +11,7 @@ TRACE_EVENT(thermal_power_allocator,
>  		 u32 total_req_power, u32 *granted_power,
>  		 u32 total_granted_power, size_t num_actors,
>  		 u32 power_range, u32 max_allocatable_power,
> -		 unsigned long current_temp, s32 delta_temp),
> +		 int current_temp, s32 delta_temp),
>  	TP_ARGS(tz, req_power, total_req_power, granted_power,
>  		total_granted_power, num_actors, power_range,
>  		max_allocatable_power, current_temp, delta_temp),
> @@ -24,7 +24,7 @@ TRACE_EVENT(thermal_power_allocator,
>  		__field(size_t,        num_actors               )
>  		__field(u32,           power_range              )
>  		__field(u32,           max_allocatable_power    )
> -		__field(unsigned long, current_temp             )
> +		__field(int,           current_temp             )
>  		__field(s32,           delta_temp               )
>  	),
>  	TP_fast_assign(
> @@ -42,7 +42,7 @@ TRACE_EVENT(thermal_power_allocator,
>  		__entry->delta_temp = delta_temp;
>  	),
>  
> -	TP_printk("thermal_zone_id=%d req_power={%s} total_req_power=%u granted_power={%s} total_granted_power=%u power_range=%u max_allocatable_power=%u current_temperature=%lu delta_temperature=%d",
> +	TP_printk("thermal_zone_id=%d req_power={%s} total_req_power=%u granted_power={%s} total_granted_power=%u power_range=%u max_allocatable_power=%u current_temperature=%d delta_temperature=%d",
>  		__entry->tz_id,
>  		__print_array(__get_dynamic_array(req_power),
>                                __entry->num_actors, 4),