Commit Graph

12 Commits

Author SHA1 Message Date
Thomas Gleixner
873e65bc09 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 167
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation version 2 of the license this program
  is distributed in the hope that it will be useful but without any
  warranty without even the implied warranty of merchantability or
  fitness for a particular purpose see the gnu general public license
  for more details you should have received a copy of the gnu general
  public license along with this program if not write to the free
  software foundation inc 59 temple place suite 330 boston ma 02111
  1307 usa

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 83 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070034.021731668@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:39 -07:00
Willy WOLFF
0d76d6e1ee thermal: fix source code documentation for parameters
Some parameters are not documented, or not present at all, in thermal
governors code.

Signed-off-by: Willy Wolff <willy.mh.wolff@gmail.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
2017-06-29 10:46:31 +08:00
Michele Di Giorgio
d0b7306d20 thermal: fix race condition when updating cooling device
When multiple thermal zones are bound to the same cooling device, multiple
kernel threads may want to update the cooling device state by calling
thermal_cdev_update(). Having cdev not protected by a mutex can lead to a race
condition. Consider the following situation with two kernel threads k1 and k2:

	    Thread k1				Thread k2
                                    ||
                                    ||  call thermal_cdev_update()
                                    ||      ...
                                    ||      set_cur_state(cdev, target);
    call power_actor_set_power()    ||
        ...                         ||
        instance->target = state;   ||
        cdev->updated = false;      ||
                                    ||      cdev->updated = true;
                                    ||      // completes execution
    call thermal_cdev_update()      ||
        // cdev->updated == true    ||
        return;                     ||
                                    \/
                                    time

k2 has already looped through the thermal instances looking for the deepest
cooling device state and is preempted right before setting cdev->updated to
true. Now, k1 runs, modifies the thermal instance state and sets cdev->updated
to false. Then, k1 is preempted and k2 continues the execution by setting
cdev->updated to true, therefore preventing k1 from performing the update.
Notice that this is not an issue if k2 looks at the instance->target modified by
k1 "after" it is assigned by k1. In fact, in this case the update will happen
anyway and k1 can safely return immediately from thermal_cdev_update().

This may lead to a situation where a thermal governor never updates the cooling
device. For example, this is the case for the step_wise governor: when calling
the function thermal_zone_trip_update(), the governor may always get a new state
equal to the old one (which, however, wasn't notified to the cooling device) and
will therefore skip the update.

CC: Zhang Rui <rui.zhang@intel.com>
CC: Eduardo Valentin <edubezval@gmail.com>
CC: Peter Feuerer <peter@piie.net>
Reported-by: Toby Huang <toby.huang@arm.com>
Signed-off-by: Michele Di Giorgio <michele.digiorgio@arm.com>
Reviewed-by: Javi Merino <javi.merino@arm.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
2016-08-08 10:57:39 +08:00
Sascha Hauer
17e8351a77 thermal: consistently use int for temperatures
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>
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
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
2015-08-03 23:15:50 +08:00
Javi Merino
bcdcbbc711 thermal: fair_share: generalize the weight concept
The fair share governor has the concept of weights, which is the
influence of each cooling device in a thermal zone.  The current
implementation forces the weights of all cooling devices in a thermal
zone to add up to a 100.  This complicates setups, as you need to know
in advance how many cooling devices you are going to have.  If you bind a
new cooling device, you have to modify all the other cooling devices
weights, which is error prone.  Furthermore, you can't specify a
"default" weight for platforms since that default value depends on the
number of cooling devices in the platform.

This patch generalizes the concept of weight by allowing any number to
be a "weight".  Weights are now relative to each other.  Platforms that
don't specify weights get the same default value for all their cooling
devices, so all their cdevs are considered to be equally influential.

It's important to note that previous users of the weights don't need to
alter the code: percentages continue to work as they used to.  This
patch just removes the constraint of all the weights in a thermal zone
having to add up to a 100.  If they do, you get the same behavior as
before.  If they don't, fair share now works for that platform.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Eduardo Valentin <edubezval@gmail.com>
Cc: Durgadoss R <durgadoss.r@intel.com>
Acked-by: Durgadoss R <durgadoss.r@intel.com>
Signed-off-by: Javi Merino <javi.merino@arm.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
2015-05-04 21:27:51 -07:00
Javi Merino
80b89172f9 thermal: fair_share: fix typo
s/asscciated/associated/

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Eduardo Valentin <edubezval@gmail.com>
Cc: Durgadoss R <durgadoss.r@intel.com>
Reviewed-by: Durgadoss R <durgadoss.r@intel.com>
Signed-off-by: Javi Merino <javi.merino@arm.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
2015-05-04 21:27:51 -07:00
Javi Merino
8b91e2cb24 thermal: fair_share: use the weight from the thermal instance
The fair share governor is not usable with thermal zones that use the
bind op and don't populate thermal_zone_parameters, the majority of
them.  Now that the weight is in the thermal instance, we can use that
in the fair share governor to allow every thermal zone to trivially use
this governor.  Furthermore, this simplifies the code.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Eduardo Valentin <edubezval@gmail.com>
Cc: Durgadoss R <durgadoss.r@intel.com>
Reviewed-by: Durgadoss R <durgadoss.r@intel.com>
Signed-off-by: Javi Merino <javi.merino@arm.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
2015-05-04 21:27:51 -07:00
Kapileshwar Singh
6cd9e9f629 thermal: of: fix cooling device weights in device tree
Currently you can specify the weight of the cooling device in the device
tree but that information is not populated to the
thermal_bind_params where the fair share governor expects it to
be.  The of thermal zone device doesn't have a thermal_bind_params
structure and arguably it's better to pass the weight inside the
thermal_instance as it is specific to the bind of a cooling device to a
thermal zone parameter.

Core thermal code is fixed to populate the weight in the instance from
the thermal_bind_params, so platform code that was passing the weight
inside the thermal_bind_params continue to work seamlessly.

While we are at it, create a default value for the weight parameter for
those thermal zones that currently don't define it and remove the
hardcoded default in of-thermal.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Len Brown <lenb@kernel.org>
Cc: Peter Feuerer <peter@piie.net>
Cc: Darren Hart <dvhart@infradead.org>
Cc: Eduardo Valentin <edubezval@gmail.com>
Cc: Kukjin Kim <kgene@kernel.org>
Cc: Durgadoss R <durgadoss.r@intel.com>
Signed-off-by: Kapileshwar Singh <kapileshwar.singh@arm.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
2015-05-04 21:27:50 -07:00
Punit Agrawal
208cd822a1 thermal: trace: Trace when temperature is above a trip point
Create a new event to trace when the temperature is above a trip
point. Use the trace-point when handling non-critical and critical
trip pionts.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Eduardo Valentin <edubezval@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Punit Agrawal <punit.agrawal@arm.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
2014-07-29 09:28:43 -04:00
Zhang Rui
80a26a5c22 Thermal: build thermal governors into thermal_sys module
The thermal governors are part of the thermal framework,
rather than a seperate feature/module.
Because the generic thermal layer can not work without
thermal governors, and it must load the thermal governors
during its initialization.

Build them into one module in this patch.

This also fix a problem that the generic thermal layer does not
work when CONFIG_THERMAL=m and CONFIG_THERMAL_GOV_XXX=y.

Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Acked-by: Eduardo Valentin <eduardo.valentin@ti.com>
Acked-by: Durgadoss R <durgadoss.r@intel.com>
2013-04-14 23:28:43 +08:00
Sachin Kamat
621769334b thermal: fair_share: Add missing static storage class specifiers
Fixes the following sparse warnings:
drivers/thermal/fair_share.c:80:5: warning:
symbol 'fair_share_throttle' was not declared. Should it be static?
drivers/thermal/fair_share.c:111:25: warning:
symbol 'thermal_gov_fair_share' was not declared. Should it be static?

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Acked-by: Durgadoss R <durgadoss.r@intel.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
2012-11-05 14:00:10 +08:00
Durgadoss R
4ccc5743ae Thermal: Introduce fair_share thermal governor
This patch introduces a simple 'weight' based
governor named fair_share governor. Whenever the
thermal framework gets notified of the trip point
violation, this governor (if configured), throttles
the cooling devices associated with a thermal zone.

This mapping between a thermal zone and a cooling device
and the effectiveness of cooling are provided in the
platform layer.

Signed-off-by: Durgadoss R <durgadoss.r@intel.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
2012-11-05 14:00:07 +08:00