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* [PATCHv4 11/15] Thermal: Introduce a step_wise thermal governor
@ 2012-09-21  6:36 Durgadoss R
  0 siblings, 0 replies; 6+ messages in thread
From: Durgadoss R @ 2012-09-21  6:36 UTC (permalink / raw)
  To: lenb, rui.zhang; +Cc: linux-acpi, eduardo.valentin, Durgadoss R

This patch adds a simple step_wise governor to the
generic thermal layer. This algorithm throttles the
cooling devices in a linear fashion. If the 'trend'
is heating, it throttles by one step. And if the
thermal trend is cooling it de-throttles by one step.

This actually moves the throttling logic from thermal_sys.c
and puts inside step_wise.c, without any change.

Signed-off-by: Durgadoss R <durgadoss.r@intel.com>
---
 * This patch is a modified version of v4 series submitted here:
   http://www.spinics.net/lists/linux-acpi/msg37375.html
 * This patch removes the Kconfig option to always select
   step_wise as default governor.
 * I will submit a separate patch to let the user select
   a default thermal governor like how it is being done
   for cpufreq governors.
 drivers/thermal/Kconfig     |    6 ++
 drivers/thermal/Makefile    |    1 +
 drivers/thermal/step_wise.c |  194 +++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 201 insertions(+)
 create mode 100644 drivers/thermal/step_wise.c

diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
index 2200912..becec31 100644
--- a/drivers/thermal/Kconfig
+++ b/drivers/thermal/Kconfig
@@ -59,3 +59,9 @@ config FAIR_SHARE
 	depends on THERMAL
 	help
 	  Enable this to manage platform thermals using fair-share governor.
+
+config STEP_WISE
+	bool "Step_wise thermal governor"
+	depends on THERMAL
+	help
+	  Enable this to manage platform thermals using a simple linear
diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile
index 30540dd..4e53c00 100644
--- a/drivers/thermal/Makefile
+++ b/drivers/thermal/Makefile
@@ -8,3 +8,4 @@ obj-$(CONFIG_SPEAR_THERMAL)		+= spear_thermal.o
 obj-$(CONFIG_RCAR_THERMAL)	+= rcar_thermal.o
 obj-$(CONFIG_EXYNOS_THERMAL)		+= exynos_thermal.o
 obj-$(CONFIG_FAIR_SHARE)		+= fair_share.o
+obj-$(CONFIG_STEP_WISE)			+= step_wise.o
diff --git a/drivers/thermal/step_wise.c b/drivers/thermal/step_wise.c
new file mode 100644
index 0000000..3f9cfcf
--- /dev/null
+++ b/drivers/thermal/step_wise.c
@@ -0,0 +1,194 @@
+/*
+ *  step_wise.c - A step-by-step Thermal throttling governor
+ *
+ *  Copyright (C) 2012 Intel Corp
+ *  Copyright (C) 2012 Durgadoss R <durgadoss.r@intel.com>
+ *
+ *  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ *  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.
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/module.h>
+#include <linux/thermal.h>
+
+#include "thermal_core.h"
+
+/*
+ * If the temperature is higher than a trip point,
+ *    a. if the trend is THERMAL_TREND_RAISING, use higher cooling
+ *       state for this trip point
+ *    b. if the trend is THERMAL_TREND_DROPPING, use lower cooling
+ *       state for this trip point
+ */
+static unsigned long get_target_state(struct thermal_instance *instance,
+					enum thermal_trend trend)
+{
+	struct thermal_cooling_device *cdev = instance->cdev;
+	unsigned long cur_state;
+
+	cdev->ops->get_cur_state(cdev, &cur_state);
+
+	if (trend == THERMAL_TREND_RAISING) {
+		cur_state = cur_state < instance->upper ?
+			    (cur_state + 1) : instance->upper;
+	} else if (trend == THERMAL_TREND_DROPPING) {
+		cur_state = cur_state > instance->lower ?
+			    (cur_state - 1) : instance->lower;
+	}
+
+	return cur_state;
+}
+
+static void update_passive_instance(struct thermal_zone_device *tz,
+				enum thermal_trip_type type, int value)
+{
+	/*
+	 * If value is +1, activate a passive instance.
+	 * If value is -1, deactivate a passive instance.
+	 */
+	if (type == THERMAL_TRIP_PASSIVE || type == THERMAL_TRIPS_NONE)
+		tz->passive += value;
+}
+
+static void update_instance_for_throttle(struct thermal_zone_device *tz,
+				int trip, enum thermal_trip_type trip_type,
+				enum thermal_trend trend)
+{
+	struct thermal_instance *instance;
+
+	list_for_each_entry(instance, &tz->thermal_instances, tz_node) {
+		if (instance->trip != trip)
+			continue;
+
+		instance->target = get_target_state(instance, trend);
+
+		/* Activate a passive thermal instance */
+		if (instance->target == THERMAL_NO_TARGET)
+			update_passive_instance(tz, trip_type, 1);
+
+		instance->cdev->updated = false; /* cdev needs update */
+	}
+}
+
+static void update_instance_for_dethrottle(struct thermal_zone_device *tz,
+				int trip, enum thermal_trip_type trip_type)
+{
+	struct thermal_instance *instance;
+	struct thermal_cooling_device *cdev;
+	unsigned long cur_state;
+
+	list_for_each_entry(instance, &tz->thermal_instances, tz_node) {
+		if (instance->trip != trip ||
+			instance->target == THERMAL_NO_TARGET)
+			continue;
+
+		cdev = instance->cdev;
+		cdev->ops->get_cur_state(cdev, &cur_state);
+
+		instance->target = cur_state > instance->lower ?
+			    (cur_state - 1) : THERMAL_NO_TARGET;
+
+		/* Deactivate a passive thermal instance */
+		if (instance->target == THERMAL_NO_TARGET)
+			update_passive_instance(tz, trip_type, -1);
+
+		cdev->updated = false; /* cdev needs update */
+	}
+}
+
+static void thermal_zone_trip_update(struct thermal_zone_device *tz, int trip)
+{
+	long trip_temp;
+	enum thermal_trip_type trip_type;
+	enum thermal_trend trend;
+
+	if (trip == THERMAL_TRIPS_NONE) {
+		trip_temp = tz->forced_passive;
+		trip_type = THERMAL_TRIPS_NONE;
+	} else {
+		tz->ops->get_trip_temp(tz, trip, &trip_temp);
+		tz->ops->get_trip_type(tz, trip, &trip_type);
+	}
+
+	trend = get_tz_trend(tz, trip);
+
+	mutex_lock(&tz->lock);
+
+	if (tz->temperature >= trip_temp)
+		update_instance_for_throttle(tz, trip, trip_type, trend);
+	else
+		update_instance_for_dethrottle(tz, trip, trip_type);
+
+	mutex_unlock(&tz->lock);
+}
+
+/**
+ * step_wise_throttle - throttles devices asscciated with the given zone
+ * @tz - thermal_zone_device
+ * @trip - the trip point
+ * @trip_type - type of the trip point
+ *
+ * Throttling Logic: This uses the trend of the thermal zone to throttle.
+ * If the thermal zone is 'heating up' this throttles all the cooling
+ * devices associated with the zone and its particular trip point, by one
+ * step. If the zone is 'cooling down' it brings back the performance of
+ * the devices by one step.
+ */
+int step_wise_throttle(struct thermal_zone_device *tz, int trip)
+{
+	struct thermal_instance *instance;
+
+	thermal_zone_trip_update(tz, trip);
+
+	if (tz->forced_passive)
+		thermal_zone_trip_update(tz, THERMAL_TRIPS_NONE);
+
+	mutex_lock(&tz->lock);
+
+	list_for_each_entry(instance, &tz->thermal_instances, tz_node)
+		thermal_cdev_update(instance->cdev);
+
+	mutex_unlock(&tz->lock);
+
+	return 0;
+}
+
+struct thermal_governor thermal_gov_step_wise = {
+	.name		= DEFAULT_THERMAL_GOVERNOR,
+	.throttle	= step_wise_throttle,
+	.owner		= THIS_MODULE,
+};
+
+static int __init thermal_gov_step_wise_init(void)
+{
+	return thermal_register_governor(&thermal_gov_step_wise);
+}
+
+static void __exit thermal_gov_step_wise_exit(void)
+{
+	thermal_unregister_governor(&thermal_gov_step_wise);
+}
+
+/* This should load after thermal framework */
+fs_initcall(thermal_gov_step_wise_init);
+module_exit(thermal_gov_step_wise_exit);
+
+MODULE_AUTHOR("Durgadoss R");
+MODULE_DESCRIPTION("A step-by-step thermal throttling governor");
+MODULE_LICENSE("GPL");
-- 
1.7.9.5


^ permalink raw reply related	[flat|nested] 6+ messages in thread
* [PATCHv4 00/15] Thermal_framework_enhancements
@ 2012-09-18  5:34 Durgadoss R
  2012-09-18  5:35 ` [PATCHv4 11/15] Thermal: Introduce a step_wise thermal governor Durgadoss R
  0 siblings, 1 reply; 6+ messages in thread
From: Durgadoss R @ 2012-09-18  5:34 UTC (permalink / raw)
  To: lenb, rui.zhang; +Cc: linux-acpi, eduardo.valentin, Durgadoss R

This patch series is a v4 of the series submitted here:
http://www.spinics.net/lists/linux-acpi/msg37375.html

These patches are based on Rui's tree here: (branch - next)
git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux.git

Changes since v3:
 * Rebase the patches on top of Rui's next branch
 * Register a separate governor for user space
 * Make step_wise governor as default (Kconfig change)
 * Synchronize policy_store method in thermal_sys.c
Changes since v2:
 * Made thermal_zone_params as argument to tzd_register()
 * Introduced Thermal governor register/unregister APIs
 * Added 'write' permission for policy sysfs attribute
 * Added function pointer based implemention for thermal
   governors.
 * Added a 'dummy' user space governor in thermal_sys.c
 * Renamed 'do_binding' and 'update_bind_info' functions as
   'bind_tz' and 'bind_cdev' respectively
 * Updated Documentation for all the changes
Changes since v1:
 * Created thermal_core.h
 * Removed get_cdev_by_name API, as it is no longer needed
 * Introduced thermal_bind_params inside thermal_zone_params
 * Use a single arbitrator by making thermal_cdev_update global
 * Added more documentation on EXPORT_SYMBOL APIs in thermal_sys.c
 * Various minor fixes based on comments from Rui and Eduardo.


Durgadoss R (15):
  Thermal: Refactor thermal.h file
  Thermal: Move thermal_instance to thermal_core.h
  Thermal: Add get trend, get instance API's to thermal_sys
  Thermal: Add platform level information to thermal.h
  Thermal: Pass zone parameters as argument to tzd_register
  Thermal: Add thermal governor registration APIs
  Thermal: Add a policy sysfs attribute
  Thermal: Update binding logic based on platform data
  Thermal: Make thermal_cdev_update as a global function
  Thermal: Introduce fair_share thermal governor
  Thermal: Introduce a step_wise thermal governor
  Thermal: Add a thermal notifier for user space
  Thermal: Remove throttling logic out of thermal_sys.c
  Thermal: Add a notification API
  Thermal: Add documentation for platform layer data

 Documentation/thermal/sysfs-api.txt                |   64 ++
 drivers/acpi/thermal.c                             |    6 +-
 drivers/platform/x86/acerhdf.c                     |    2 +-
 drivers/platform/x86/intel_mid_thermal.c           |    2 +-
 drivers/power/power_supply_core.c                  |    2 +-
 drivers/staging/omap-thermal/omap-thermal-common.c |    2 +-
 drivers/thermal/Kconfig                            |   19 +
 drivers/thermal/Makefile                           |    3 +
 drivers/thermal/exynos_thermal.c                   |    2 +-
 drivers/thermal/fair_share.c                       |  133 ++++
 drivers/thermal/rcar_thermal.c                     |    2 +-
 drivers/thermal/spear_thermal.c                    |    2 +-
 drivers/thermal/step_wise.c                        |  194 ++++++
 drivers/thermal/thermal_core.h                     |   53 ++
 drivers/thermal/thermal_sys.c                      |  705 +++++++++++++-------
 drivers/thermal/user_space.c                       |   68 ++
 include/linux/thermal.h                            |  128 +++-
 17 files changed, 1096 insertions(+), 291 deletions(-)
 create mode 100644 drivers/thermal/fair_share.c
 create mode 100644 drivers/thermal/step_wise.c
 create mode 100644 drivers/thermal/thermal_core.h
 create mode 100644 drivers/thermal/user_space.c

-- 
1.7.9.5


^ permalink raw reply	[flat|nested] 6+ messages in thread
end of thread, other threads:[~2012-09-21  6:36 UTC | newest]

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2012-09-18  5:34 [PATCHv4 00/15] Thermal_framework_enhancements Durgadoss R
2012-09-18  5:35 ` [PATCHv4 11/15] Thermal: Introduce a step_wise thermal governor Durgadoss R
2012-09-18  7:13   ` Zhang Rui
2012-09-18  8:11     ` R, Durgadoss
2012-09-18  8:22       ` Zhang Rui
2012-09-18  8:32         ` R, Durgadoss

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