Message ID | 1344516365-7230-9-git-send-email-durgadoss.r@intel.com (mailing list archive) |
---|---|
State | Not Applicable, archived |
Headers | show |
Hello, On Thu, Aug 09, 2012 at 06:16:00PM +0530, Durgadoss R wrote: > 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> > --- > drivers/thermal/Kconfig | 6 ++ > drivers/thermal/Makefile | 3 +- > drivers/thermal/fair_share.c | 128 ++++++++++++++++++++++++++++++++++++++++++ > include/linux/thermal.h | 9 +++ > 4 files changed, 145 insertions(+), 1 deletion(-) > create mode 100644 drivers/thermal/fair_share.c > > diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig > index 3ab2bd5..f5110c0 100644 > --- a/drivers/thermal/Kconfig > +++ b/drivers/thermal/Kconfig > @@ -27,3 +27,9 @@ config SPEAR_THERMAL > help > Enable this to plug the SPEAr thermal sensor driver into the Linux > thermal framework > + > +config FAIR_SHARE > + bool "Fair-share thermal governor" > + depends on THERMAL > + help > + Enable this to manage platform thermals using fair-share governor. > diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile > index a9fff0b..4ffe1a8 100644 > --- a/drivers/thermal/Makefile > +++ b/drivers/thermal/Makefile > @@ -3,4 +3,5 @@ > # > > obj-$(CONFIG_THERMAL) += thermal_sys.o > -obj-$(CONFIG_SPEAR_THERMAL) += spear_thermal.o > \ No newline at end of file > +obj-$(CONFIG_SPEAR_THERMAL) += spear_thermal.o > +obj-$(CONFIG_FAIR_SHARE) += fair_share.o > diff --git a/drivers/thermal/fair_share.c b/drivers/thermal/fair_share.c > new file mode 100644 > index 0000000..b8c8d45 > --- /dev/null > +++ b/drivers/thermal/fair_share.c > @@ -0,0 +1,128 @@ > +/* > + * fair_share.c - A simple weight based Thermal 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> > + > +/** > + * get_trip_level: - obtains the current trip level for a zone > + * @tz: thermal zone device > + */ > +static int get_trip_level(struct thermal_zone_device *tz) > +{ > + int count = 0; > + unsigned long trip_temp; > + > + if (tz->trips == 0 || !tz->ops->get_trip_temp) > + return 0; > + > + for (count = 0; count < tz->trips; count++) { > + tz->ops->get_trip_temp(tz, count, &trip_temp); > + if (tz->temperature < trip_temp) > + break; > + } > + return count; > +} > + > +static long get_target_state(struct thermal_zone_device *tz, > + struct thermal_cooling_device *cdev, int weight, int level) > +{ > + unsigned long max_state; > + > + cdev->ops->get_max_state(cdev, &max_state); > + > + return (long)(weight * level * max_state) / (100 * tz->trips); > +} > + > +static void thermal_cdev_update(struct thermal_cooling_device *cdev) > +{ > + struct thermal_instance *instance; > + unsigned long target = 0; > + > + mutex_lock(&cdev->lock); > + > + /* Make sure cdev enters the deepest cooling state */ > + list_for_each_entry(instance, &cdev->thermal_instances, cdev_node) { > + if (instance->target > target) > + target = instance->target; > + } > + > + mutex_unlock(&cdev->lock); > + > + cdev->ops->set_cur_state(cdev, target); > +} I believe Rui has already provided an arbitrator, can we reuse it here as well? > + > +/** > + * fair_share_throttle - throttles devices asscciated with the given zone > + * @tz - thermal_zone_device > + * > + * Throttling Logic: This uses three parameters to calculate the new > + * throttle state of the cooling devices associated with the given zone. > + * > + * Parameters used for Throttling: > + * P1. max_state: Maximum throttle state exposed by the cooling device. > + * P2. weight[i]/100: > + * How 'effective' the 'i'th device is, in cooling the given zone. > + * P3. cur_trip_level/max_no_of_trips: > + * This describes the extent to which the devices should be throttled. > + * We do not want to throttle too much when we trip a lower temperature, > + * whereas the throttling is at full swing if we trip critical levels. > + * (Heavily assumes the trip points are in ascending order) > + * new_state of cooling device = P3 * P2 * P1 > + */ > +void fair_share_throttle(struct thermal_zone_device *tz, int trip) > +{ > + struct thermal_zone_params *tzp; > + struct thermal_cooling_device *cdev; > + struct thermal_instance *instance; > + int i; > + int cur_trip_level = get_trip_level(tz); > + > + if (!tz->tzp) > + return; > + > + tzp = tz->tzp; > + > + for (i = 0; i < tzp->num_cdevs; i++) { > + cdev = get_cdev_by_name(tzp->cdevs_name[i]); > + if (!cdev) > + continue; > + > + instance = get_thermal_instance(tz, cdev, trip); > + if (!instance) > + continue; > + > + instance->target = get_target_state(tz, cdev, > + tzp->weights[i], cur_trip_level); > + > + thermal_cdev_update(cdev); > + } > +} > +EXPORT_SYMBOL(fair_share_throttle); > + > +MODULE_AUTHOR("Durgadoss R"); > +MODULE_DESCRIPTION("A simple weight based thermal throttling governor"); > +MODULE_LICENSE("GPL"); > diff --git a/include/linux/thermal.h b/include/linux/thermal.h > index 1d49f05..4e2dc2c 100644 > --- a/include/linux/thermal.h > +++ b/include/linux/thermal.h > @@ -257,6 +257,15 @@ struct thermal_instance *get_thermal_instance(struct thermal_zone_device *, > */ > extern int (*get_platform_thermal_params)(struct thermal_zone_device *); > > +#ifdef CONFIG_FAIR_SHARE > +extern void fair_share_throttle(struct thermal_zone_device *tz, int trip); > +#else > +static inline void fair_share_throttle(struct thermal_zone_device *tz, int trip) > +{ > + return; > +} > +#endif > + > #ifdef CONFIG_NET > extern int thermal_generate_netlink_event(u32 orig, enum events event); > #else > -- > 1.7.9.5 > -- To unsubscribe from this list: send the line "unsubscribe linux-pm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Hi Eduardo, > > +static long get_target_state(struct thermal_zone_device *tz, > > + struct thermal_cooling_device *cdev, int weight, int level) > > +{ > > + unsigned long max_state; > > + > > + cdev->ops->get_max_state(cdev, &max_state); > > + > > + return (long)(weight * level * max_state) / (100 * tz->trips); > > +} > > + > > +static void thermal_cdev_update(struct thermal_cooling_device *cdev) > > +{ > > + struct thermal_instance *instance; > > + unsigned long target = 0; > > + > > + mutex_lock(&cdev->lock); > > + > > + /* Make sure cdev enters the deepest cooling state */ > > + list_for_each_entry(instance, &cdev->thermal_instances, > cdev_node) { > > + if (instance->target > target) > > + target = instance->target; > > + } > > + > > + mutex_unlock(&cdev->lock); > > + > > + cdev->ops->set_cur_state(cdev, target); > > +} > > I believe Rui has already provided an arbitrator, can we reuse it here as well? I thought about this. I was of the opinion a governor can choose to do arbitration in its own specific way. For example, The fair_share does not check 'cdev->updated' value whenever it tries to update the state of a cooling device. Thanks, Durga -- To unsubscribe from this list: send the line "unsubscribe linux-pm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
hello, On Tue, Aug 21, 2012 at 05:59:00AM +0000, R, Durgadoss wrote: > Hi Eduardo, > > > > +static long get_target_state(struct thermal_zone_device *tz, > > > + struct thermal_cooling_device *cdev, int weight, int level) > > > +{ > > > + unsigned long max_state; > > > + > > > + cdev->ops->get_max_state(cdev, &max_state); > > > + > > > + return (long)(weight * level * max_state) / (100 * tz->trips); > > > +} > > > + > > > +static void thermal_cdev_update(struct thermal_cooling_device *cdev) > > > +{ > > > + struct thermal_instance *instance; > > > + unsigned long target = 0; > > > + > > > + mutex_lock(&cdev->lock); > > > + > > > + /* Make sure cdev enters the deepest cooling state */ > > > + list_for_each_entry(instance, &cdev->thermal_instances, > > cdev_node) { > > > + if (instance->target > target) > > > + target = instance->target; > > > + } > > > + > > > + mutex_unlock(&cdev->lock); > > > + > > > + cdev->ops->set_cur_state(cdev, target); > > > +} > > > > I believe Rui has already provided an arbitrator, can we reuse it here as well? > > I thought about this. I was of the opinion a governor can choose to do arbitration > in its own specific way. For example, The fair_share does not check 'cdev->updated' > value whenever it tries to update the state of a cooling device. I see. the arbitration starts to get more and more complex. not to talk about constraints coming from performance domain and not thermal. I'd still try to find a central point for doing the arbitration, this way we grow the code in a scalable way... > > Thanks, > Durga -- To unsubscribe from this list: send the line "unsubscribe linux-pm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig index 3ab2bd5..f5110c0 100644 --- a/drivers/thermal/Kconfig +++ b/drivers/thermal/Kconfig @@ -27,3 +27,9 @@ config SPEAR_THERMAL help Enable this to plug the SPEAr thermal sensor driver into the Linux thermal framework + +config FAIR_SHARE + bool "Fair-share thermal governor" + depends on THERMAL + help + Enable this to manage platform thermals using fair-share governor. diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile index a9fff0b..4ffe1a8 100644 --- a/drivers/thermal/Makefile +++ b/drivers/thermal/Makefile @@ -3,4 +3,5 @@ # obj-$(CONFIG_THERMAL) += thermal_sys.o -obj-$(CONFIG_SPEAR_THERMAL) += spear_thermal.o \ No newline at end of file +obj-$(CONFIG_SPEAR_THERMAL) += spear_thermal.o +obj-$(CONFIG_FAIR_SHARE) += fair_share.o diff --git a/drivers/thermal/fair_share.c b/drivers/thermal/fair_share.c new file mode 100644 index 0000000..b8c8d45 --- /dev/null +++ b/drivers/thermal/fair_share.c @@ -0,0 +1,128 @@ +/* + * fair_share.c - A simple weight based Thermal 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> + +/** + * get_trip_level: - obtains the current trip level for a zone + * @tz: thermal zone device + */ +static int get_trip_level(struct thermal_zone_device *tz) +{ + int count = 0; + unsigned long trip_temp; + + if (tz->trips == 0 || !tz->ops->get_trip_temp) + return 0; + + for (count = 0; count < tz->trips; count++) { + tz->ops->get_trip_temp(tz, count, &trip_temp); + if (tz->temperature < trip_temp) + break; + } + return count; +} + +static long get_target_state(struct thermal_zone_device *tz, + struct thermal_cooling_device *cdev, int weight, int level) +{ + unsigned long max_state; + + cdev->ops->get_max_state(cdev, &max_state); + + return (long)(weight * level * max_state) / (100 * tz->trips); +} + +static void thermal_cdev_update(struct thermal_cooling_device *cdev) +{ + struct thermal_instance *instance; + unsigned long target = 0; + + mutex_lock(&cdev->lock); + + /* Make sure cdev enters the deepest cooling state */ + list_for_each_entry(instance, &cdev->thermal_instances, cdev_node) { + if (instance->target > target) + target = instance->target; + } + + mutex_unlock(&cdev->lock); + + cdev->ops->set_cur_state(cdev, target); +} + +/** + * fair_share_throttle - throttles devices asscciated with the given zone + * @tz - thermal_zone_device + * + * Throttling Logic: This uses three parameters to calculate the new + * throttle state of the cooling devices associated with the given zone. + * + * Parameters used for Throttling: + * P1. max_state: Maximum throttle state exposed by the cooling device. + * P2. weight[i]/100: + * How 'effective' the 'i'th device is, in cooling the given zone. + * P3. cur_trip_level/max_no_of_trips: + * This describes the extent to which the devices should be throttled. + * We do not want to throttle too much when we trip a lower temperature, + * whereas the throttling is at full swing if we trip critical levels. + * (Heavily assumes the trip points are in ascending order) + * new_state of cooling device = P3 * P2 * P1 + */ +void fair_share_throttle(struct thermal_zone_device *tz, int trip) +{ + struct thermal_zone_params *tzp; + struct thermal_cooling_device *cdev; + struct thermal_instance *instance; + int i; + int cur_trip_level = get_trip_level(tz); + + if (!tz->tzp) + return; + + tzp = tz->tzp; + + for (i = 0; i < tzp->num_cdevs; i++) { + cdev = get_cdev_by_name(tzp->cdevs_name[i]); + if (!cdev) + continue; + + instance = get_thermal_instance(tz, cdev, trip); + if (!instance) + continue; + + instance->target = get_target_state(tz, cdev, + tzp->weights[i], cur_trip_level); + + thermal_cdev_update(cdev); + } +} +EXPORT_SYMBOL(fair_share_throttle); + +MODULE_AUTHOR("Durgadoss R"); +MODULE_DESCRIPTION("A simple weight based thermal throttling governor"); +MODULE_LICENSE("GPL"); diff --git a/include/linux/thermal.h b/include/linux/thermal.h index 1d49f05..4e2dc2c 100644 --- a/include/linux/thermal.h +++ b/include/linux/thermal.h @@ -257,6 +257,15 @@ struct thermal_instance *get_thermal_instance(struct thermal_zone_device *, */ extern int (*get_platform_thermal_params)(struct thermal_zone_device *); +#ifdef CONFIG_FAIR_SHARE +extern void fair_share_throttle(struct thermal_zone_device *tz, int trip); +#else +static inline void fair_share_throttle(struct thermal_zone_device *tz, int trip) +{ + return; +} +#endif + #ifdef CONFIG_NET extern int thermal_generate_netlink_event(u32 orig, enum events event); #else
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> --- drivers/thermal/Kconfig | 6 ++ drivers/thermal/Makefile | 3 +- drivers/thermal/fair_share.c | 128 ++++++++++++++++++++++++++++++++++++++++++ include/linux/thermal.h | 9 +++ 4 files changed, 145 insertions(+), 1 deletion(-) create mode 100644 drivers/thermal/fair_share.c