| Message ID | 1448464186-26289-2-git-send-email-javi.merino@arm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Delegated to: | Eduardo Valentin |
| Headers | show |
Thanks for moving this forward Javi, Few comments inline. On Wed, Nov 25, 2015 at 03:09:43PM +0000, Javi Merino wrote: > Add the ability to stack thermal zones on top of each other, creating a > hierarchy of thermal zones. > > Cc: Zhang Rui <rui.zhang@intel.com> > Cc: Eduardo Valentin <edubezval@gmail.com> > Signed-off-by: Javi Merino <javi.merino@arm.com> > --- > Documentation/thermal/sysfs-api.txt | 39 +++++++ > drivers/thermal/thermal_core.c | 210 +++++++++++++++++++++++++++++++++++- > include/linux/thermal.h | 41 ++++++- > 3 files changed, 284 insertions(+), 6 deletions(-) > > diff --git a/Documentation/thermal/sysfs-api.txt b/Documentation/thermal/sysfs-api.txt > index 10f062ea6bc2..dda24a0bdeec 100644 > --- a/Documentation/thermal/sysfs-api.txt > +++ b/Documentation/thermal/sysfs-api.txt > @@ -72,6 +72,45 @@ temperature) and throttle appropriate devices. > It deletes the corresponding entry form /sys/class/thermal folder and > unbind all the thermal cooling devices it uses. > > + > +1.1.3 int thermal_zone_add_subtz(struct thermal_zone_device *tz, > + struct thermal_zone_device *subtz) This does not match the signature proposed below in the code. But hold on, check my comments there too. > + > + Add subtz to the list of slaves of tz. This lets you create a > + hierarchy of thermal zones. The hierarchy must be a Direct > + Acyclic Graph (DAG). If a loop is detected, > + thermal_zone_get_temp() will return -EDEADLK to prevent the > + deadlock. thermal_zone_add_subtz() does not affect subtz. > + > + When calculating the temperature of thermal zone tz, report it as > + an aggregation of the temperatures of the sub thermal zones. For > + details of the aggregation function see the enum > + thermal_aggregation_function. > + > + For example, if you have an SoC with a thermal sensor in each cpu > + of the two cpus you could have a thermal zone to monitor each > + sensor, let's call them cpu0_tz and cpu1_tz. You could then have a > + a SoC thermal zone (soc_tz) without a get_temp() op which can be > + configured like this: > + > + thermal_zone_add_subtz(soc_tz, cpu0_tz); > + thermal_zone_add_subtz(soc_tz, cpu1_tz); > + > + Now soc_tz's temperature is the aggregation of cpu0_tz and > + cpu1_tz. > + > + > +1.1.4 int thermal_zone_del_subtz(struct thermal_zone_device *tz, > + struct thermal_zone_device *subtz) > + > + Delete subtz from the slave thermal zones of tz. This basically > + reverses what thermal_zone_add_subtz() does. If tz still has > + other slave thermal zones, its temperature would be the > + aggregation of the remaining slave thermal zones. If tz no longer > + has slave thermal zones, thermal_zone_get_temp() will return > + -EINVAL. > + > + > 1.2 thermal cooling device interface > 1.2.1 struct thermal_cooling_device *thermal_cooling_device_register(char *name, > void *devdata, struct thermal_cooling_device_ops *) > diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c > index d9e525cc9c1c..98bdb63b3b95 100644 > --- a/drivers/thermal/thermal_core.c > +++ b/drivers/thermal/thermal_core.c > @@ -61,6 +61,20 @@ static DEFINE_MUTEX(thermal_governor_lock); > > static struct thermal_governor *def_governor; > > +/** > + * struct thermal_zone_link - a link between "master" and "slave" thermal zones > + * @weight: weight of the @slave thermal zone in the master > + * calculation. Used when the master thermal zone's > + * aggregation function is THERMAL_AGG_WEIGHTED_AVG > + * @slave: pointer to the slave thermal zone > + * @node: list node in the master thermal zone's slave_tzs list. > + */ > +struct thermal_zone_link { > + int weight; > + struct thermal_zone_device *slave; > + struct list_head node; > +}; > + How about this struct be in thermal_core.h? I think we should support also aggregation functions implemented by drivers, and therefore they should have access to this data. Also they will probably need a driver_data too. > static struct thermal_governor *__find_governor(const char *name) > { > struct thermal_governor *pos; > @@ -465,6 +479,80 @@ static void handle_thermal_trip(struct thermal_zone_device *tz, int trip) > } > > /** > + * get_subtz_temp() - get the aggregate temperature of all the sub thermal zones > + * @tz: thermal zone pointer > + * @temp: pointer in which to store the result > + * > + * Go through all the thermal zones listed in @tz slave_tzs and > + * calculate the aggregate temperature of all of them. The result is > + * stored in @temp. The function used for aggregation is defined by > + * the thermal zone's "slave_agg_function" parameter. It can only be > + * THERMAL_AGG_MAX or THERMAL_AGG_WEIGHTED_AVG. If THERMAL_AGG_MAX is > + * used then the @temp holds the maximum temperature of all slave > + * thermal zones. With THERMAL_AGG_WEIGHTED_AVG a weighted average of > + * all temperatures is calculated. Each thermal zone's temperature is > + * multiplied by its weight and the result is divided by the sum of > + * all weights. If all weights are zero, the result is the average > + * weight of the thermal zones. > + * > + * Return: 0 on success, -EINVAL if there are no slave thermal zones, > + * -E* if thermal_zone_get_temp() fails for any of the slave thermal > + * zones. > + */ > +static int get_subtz_temp(struct thermal_zone_device *tz, int *temp) > +{ > + struct thermal_zone_link *link; > + int ret_temp, total_weight = 0; > + bool all_weights_are_zero = false; > + > + if (list_empty(&tz->slave_tzs)) > + return -EINVAL; > + > + if (tz->slave_agg_function == THERMAL_AGG_WEIGHTED_AVG) { > + int total_instances = 0; > + > + list_for_each_entry(link, &tz->slave_tzs, node) { > + total_weight += link->weight; > + total_instances++; > + } > + > + if (!total_weight) { > + all_weights_are_zero = true; > + total_weight = total_instances; > + } else { > + all_weights_are_zero = false; > + } > + > + ret_temp = 0; > + } else if (tz->slave_agg_function == THERMAL_AGG_MAX) { > + ret_temp = INT_MIN; > + } > + > + list_for_each_entry(link, &tz->slave_tzs, node) { > + int this_temp, ret; > + > + ret = thermal_zone_get_temp(link->slave, &this_temp); > + if (ret) > + return ret; > + > + if (tz->slave_agg_function == THERMAL_AGG_MAX) { > + if (this_temp > ret_temp) > + ret_temp = this_temp; > + } else if (tz->slave_agg_function == THERMAL_AGG_WEIGHTED_AVG) { > + int weight = all_weights_are_zero ? 1 : link->weight; > + > + ret_temp += weight * this_temp; > + } > + } > + > + if (tz->slave_agg_function == THERMAL_AGG_WEIGHTED_AVG) > + ret_temp /= total_weight; > + > + *temp = ret_temp; > + return 0; > +} > + > +/** > * thermal_zone_get_temp() - returns the temperature of a thermal zone > * @tz: a valid pointer to a struct thermal_zone_device > * @temp: a valid pointer to where to store the resulting temperature. > @@ -481,11 +569,22 @@ int thermal_zone_get_temp(struct thermal_zone_device *tz, int *temp) > int crit_temp = INT_MAX; > enum thermal_trip_type type; > > - if (!tz || IS_ERR(tz) || !tz->ops->get_temp) > + if (!tz || IS_ERR(tz)) > goto exit; > > + /* Avoid loops */ > + if (tz->slave_tz_visited) > + return -EDEADLK; > + > mutex_lock(&tz->lock); > > + tz->slave_tz_visited = true; > + > + if (!tz->ops->get_temp) { > + ret = get_subtz_temp(tz, temp); > + goto unlock; > + } > + We probably need to revisit this. Are you able to set emulation temperature in thermal zone that has aggregation functions? > ret = tz->ops->get_temp(tz, temp); > > if (IS_ENABLED(CONFIG_THERMAL_EMULATION) && tz->emul_temperature) { > @@ -506,7 +605,9 @@ int thermal_zone_get_temp(struct thermal_zone_device *tz, int *temp) > if (!ret && *temp < crit_temp) > *temp = tz->emul_temperature; > } > - > + > +unlock: > + tz->slave_tz_visited = false; > mutex_unlock(&tz->lock); > exit: > return ret; > @@ -540,9 +641,6 @@ void thermal_zone_device_update(struct thermal_zone_device *tz) > { > int count; > > - if (!tz->ops->get_temp) > - return; > - > update_temperature(tz); > > for (count = 0; count < tz->trips; count++) > @@ -1785,10 +1883,17 @@ struct thermal_zone_device *thermal_zone_device_register(const char *type, > if (trips > 0 && (!ops->get_trip_type || !ops->get_trip_temp)) > return ERR_PTR(-EINVAL); > > + if (tzp && (tzp->agg_func != THERMAL_AGG_MAX) && > + (tzp->agg_func != THERMAL_AGG_WEIGHTED_AVG)) > + return ERR_PTR(-EINVAL); > + > tz = kzalloc(sizeof(struct thermal_zone_device), GFP_KERNEL); > if (!tz) > return ERR_PTR(-ENOMEM); > > + if (tzp) > + tz->slave_agg_function = tzp->agg_func; > + INIT_LIST_HEAD(&tz->slave_tzs); > INIT_LIST_HEAD(&tz->thermal_instances); > idr_init(&tz->idr); > mutex_init(&tz->lock); > @@ -1921,6 +2026,7 @@ void thermal_zone_device_unregister(struct thermal_zone_device *tz) > const struct thermal_zone_params *tzp; > struct thermal_cooling_device *cdev; > struct thermal_zone_device *pos = NULL; > + struct thermal_zone_link *link, *tmp; > > if (!tz) > return; > @@ -1958,6 +2064,9 @@ void thermal_zone_device_unregister(struct thermal_zone_device *tz) > > mutex_unlock(&thermal_list_lock); > > + list_for_each_entry_safe(link, tmp, &tz->slave_tzs, node) > + thermal_zone_del_subtz(tz, link->slave); > + > thermal_zone_device_set_polling(tz, 0); > > if (tz->type[0]) > @@ -1980,6 +2089,97 @@ void thermal_zone_device_unregister(struct thermal_zone_device *tz) > EXPORT_SYMBOL_GPL(thermal_zone_device_unregister); > > /** > + * thermal_zone_add_subtz() - add a sub thermal zone to a thermal zone > + * @tz: pointer to the master thermal zone > + * @subtz: pointer to the slave thermal zone > + * @weight: relative contribution of the sub thermal zone > + * > + * Add @subtz to the list of slave thermal zones of @tz. If @tz > + * doesn't provide a get_temp() op, its temperature will be calculated > + * as a combination of the temperatures of its sub thermal zones. The > + * @weight is the relative contribution of this thermal zone when > + * using THERMAL_AGG_WEIGHTED_AVG. Set @weight to > + * THERMAL_WEIGHT_DEFAULT for all sub thermal zones to do a simple > + * average. See get_sub_tz_temp() for more information on how the > + * temperature for @tz is calculated. > + * > + * Return: 0 on success, -EINVAL if @tz or @subtz are not valid > + * pointers, -EEXIST if the link already exists or -ENOMEM if we ran > + * out of memory. > + */ > +int thermal_zone_add_subtz(struct thermal_zone_device *tz, > + struct thermal_zone_device *subtz, int weight) > +{ > + int ret; > + struct thermal_zone_link *link; > + > + if (IS_ERR_OR_NULL(tz) || IS_ERR_OR_NULL(subtz)) > + return -EINVAL; > + > + mutex_lock(&tz->lock); > + > + list_for_each_entry(link, &tz->slave_tzs, node) { > + if (link->slave == subtz) { > + ret = -EEXIST; > + goto unlock; > + } > + } > + > + link = kzalloc(sizeof(*link), GFP_KERNEL); > + if (!link) { > + ret = -ENOMEM; > + goto unlock; > + } > + > + link->slave = subtz; > + link->weight = weight; > + list_add_tail(&link->node, &tz->slave_tzs); > + > + ret = 0; > + > +unlock: > + mutex_unlock(&tz->lock); > + > + return ret; > +} > + > +/** > + * thermal_zone_del_subtz() - delete a sub thermal zone from its master thermal zone > + * @tz: pointer to the master thermal zone > + * @subtz: pointer to the slave thermal zone > + * > + * Remove @subtz from the list of slave thermal zones of @tz. > + * > + * Return: 0 on success, -EINVAL if either thermal is invalid or if > + * @subtz is not a slave of @tz. > + */ > +int thermal_zone_del_subtz(struct thermal_zone_device *tz, > + struct thermal_zone_device *subtz) > +{ > + int ret = -EINVAL; > + struct thermal_zone_link *link; > + > + if (IS_ERR_OR_NULL(tz) || IS_ERR_OR_NULL(subtz)) > + return -EINVAL; > + > + mutex_lock(&tz->lock); > + > + list_for_each_entry(link, &tz->slave_tzs, node) { > + if (link->slave == subtz) { > + list_del(&link->node); > + kfree(link); > + > + ret = 0; > + break; > + } > + } > + > + mutex_unlock(&tz->lock); > + > + return ret; > +} > + > +/** > * thermal_zone_get_zone_by_name() - search for a zone and returns its ref > * @name: thermal zone name to fetch the temperature > * > diff --git a/include/linux/thermal.h b/include/linux/thermal.h > index 4014a59828fc..dc3d2ab77ab6 100644 > --- a/include/linux/thermal.h > +++ b/include/linux/thermal.h > @@ -40,7 +40,7 @@ > /* No upper/lower limit requirement */ > #define THERMAL_NO_LIMIT ((u32)~0) > > -/* Default weight of a bound cooling device */ > +/* Default weight for cooling devices and sub thermal zones */ > #define THERMAL_WEIGHT_DEFAULT 0 > > /* Unit conversion macros */ > @@ -89,6 +89,18 @@ enum thermal_trend { > THERMAL_TREND_DROP_FULL, /* apply lowest cooling action */ > }; > > +/** > + * enum thermal_aggregation_function - aggregation function for sub thermal zones > + * @THERMAL_AGG_MAX: calculate the maximum of all sub thermal zones > + > + * @THERMAL_AGG_WEIGHTED_AVG: calculate the weighted average of all > + * sub thermal zones > + */ > +enum thermal_aggregation_function { > + THERMAL_AGG_MAX, > + THERMAL_AGG_WEIGHTED_AVG, > +}; > + > struct thermal_zone_device_ops { > int (*bind) (struct thermal_zone_device *, > struct thermal_cooling_device *); > @@ -170,6 +182,12 @@ struct thermal_attr { > * @ops: operations this &thermal_zone_device supports > * @tzp: thermal zone parameters > * @governor: pointer to the governor for this thermal zone > + * @slave_agg_function: aggretion function to calculate the > + * temperature as a combination of the slave thermal zones > + * of this thermal zone. See enum > + * thermal_aggregation_function for valid values > + * @slave_tzs: list of thermal zones that are a slave of this thermal zone > + * @slave_tz_visited: used to detect loops in stacked thermal zones > * @governor_data: private pointer for governor data > * @thermal_instances: list of &struct thermal_instance of this thermal zone > * @idr: &struct idr to generate unique id for this zone's cooling > @@ -197,6 +215,9 @@ struct thermal_zone_device { > struct thermal_zone_device_ops *ops; > struct thermal_zone_params *tzp; > struct thermal_governor *governor; > + enum thermal_aggregation_function slave_agg_function; > + struct list_head slave_tzs; > + bool slave_tz_visited; > void *governor_data; > struct list_head thermal_instances; > struct idr idr; > @@ -311,6 +332,13 @@ struct thermal_zone_params { > * Used by thermal zone drivers (default 0). > */ > int offset; > + > + /* > + * aggregation function to use when calculating the > + * temperature as a combination of multiple sub thermal > + * zones > + */ > + enum thermal_aggregation_function agg_func; > }; > > struct thermal_genl_event { > @@ -405,6 +433,10 @@ struct thermal_cooling_device * > thermal_of_cooling_device_register(struct device_node *np, char *, void *, > const struct thermal_cooling_device_ops *); > void thermal_cooling_device_unregister(struct thermal_cooling_device *); > +int thermal_zone_add_subtz(struct thermal_zone_device *, > + struct thermal_zone_device *, int); > +int thermal_zone_del_subtz(struct thermal_zone_device *, > + struct thermal_zone_device *); > struct thermal_zone_device *thermal_zone_get_zone_by_name(const char *name); > int thermal_zone_get_temp(struct thermal_zone_device *tz, int *temp); > > @@ -457,6 +489,13 @@ thermal_of_cooling_device_register(struct device_node *np, > static inline void thermal_cooling_device_unregister( > struct thermal_cooling_device *cdev) > { } > +static inline int thermal_zone_add_subtz(struct thermal_zone_device *tz, > + struct thermal_zone_device *subtz, > + int weight) > +{ return -ENODEV; } > +static inline int thermal_zone_del_subtz(struct thermal_zone_device *tz, > + struct thermal_zone_device *subtz) > +{ return -ENODEV; } > static inline struct thermal_zone_device *thermal_zone_get_zone_by_name( > const char *name) > { return ERR_PTR(-ENODEV); } > -- > 1.9.1 > -- 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
On Wed, Mar 02, 2016 at 07:12:46PM -0800, Eduardo Valentin wrote: > > Thanks for moving this forward Javi, > > Few comments inline. > > On Wed, Nov 25, 2015 at 03:09:43PM +0000, Javi Merino wrote: > > Add the ability to stack thermal zones on top of each other, creating a > > hierarchy of thermal zones. > > + > > + if (!tz->ops->get_temp) { > > + ret = get_subtz_temp(tz, temp); > > + goto unlock; > > + } In fact, if we follow the semantics in DT, we should allow both, regular sensors (.get_temp) and subtzs. -- 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/Documentation/thermal/sysfs-api.txt b/Documentation/thermal/sysfs-api.txt index 10f062ea6bc2..dda24a0bdeec 100644 --- a/Documentation/thermal/sysfs-api.txt +++ b/Documentation/thermal/sysfs-api.txt @@ -72,6 +72,45 @@ temperature) and throttle appropriate devices. It deletes the corresponding entry form /sys/class/thermal folder and unbind all the thermal cooling devices it uses. + +1.1.3 int thermal_zone_add_subtz(struct thermal_zone_device *tz, + struct thermal_zone_device *subtz) + + Add subtz to the list of slaves of tz. This lets you create a + hierarchy of thermal zones. The hierarchy must be a Direct + Acyclic Graph (DAG). If a loop is detected, + thermal_zone_get_temp() will return -EDEADLK to prevent the + deadlock. thermal_zone_add_subtz() does not affect subtz. + + When calculating the temperature of thermal zone tz, report it as + an aggregation of the temperatures of the sub thermal zones. For + details of the aggregation function see the enum + thermal_aggregation_function. + + For example, if you have an SoC with a thermal sensor in each cpu + of the two cpus you could have a thermal zone to monitor each + sensor, let's call them cpu0_tz and cpu1_tz. You could then have a + a SoC thermal zone (soc_tz) without a get_temp() op which can be + configured like this: + + thermal_zone_add_subtz(soc_tz, cpu0_tz); + thermal_zone_add_subtz(soc_tz, cpu1_tz); + + Now soc_tz's temperature is the aggregation of cpu0_tz and + cpu1_tz. + + +1.1.4 int thermal_zone_del_subtz(struct thermal_zone_device *tz, + struct thermal_zone_device *subtz) + + Delete subtz from the slave thermal zones of tz. This basically + reverses what thermal_zone_add_subtz() does. If tz still has + other slave thermal zones, its temperature would be the + aggregation of the remaining slave thermal zones. If tz no longer + has slave thermal zones, thermal_zone_get_temp() will return + -EINVAL. + + 1.2 thermal cooling device interface 1.2.1 struct thermal_cooling_device *thermal_cooling_device_register(char *name, void *devdata, struct thermal_cooling_device_ops *) diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c index d9e525cc9c1c..98bdb63b3b95 100644 --- a/drivers/thermal/thermal_core.c +++ b/drivers/thermal/thermal_core.c @@ -61,6 +61,20 @@ static DEFINE_MUTEX(thermal_governor_lock); static struct thermal_governor *def_governor; +/** + * struct thermal_zone_link - a link between "master" and "slave" thermal zones + * @weight: weight of the @slave thermal zone in the master + * calculation. Used when the master thermal zone's + * aggregation function is THERMAL_AGG_WEIGHTED_AVG + * @slave: pointer to the slave thermal zone + * @node: list node in the master thermal zone's slave_tzs list. + */ +struct thermal_zone_link { + int weight; + struct thermal_zone_device *slave; + struct list_head node; +}; + static struct thermal_governor *__find_governor(const char *name) { struct thermal_governor *pos; @@ -465,6 +479,80 @@ static void handle_thermal_trip(struct thermal_zone_device *tz, int trip) } /** + * get_subtz_temp() - get the aggregate temperature of all the sub thermal zones + * @tz: thermal zone pointer + * @temp: pointer in which to store the result + * + * Go through all the thermal zones listed in @tz slave_tzs and + * calculate the aggregate temperature of all of them. The result is + * stored in @temp. The function used for aggregation is defined by + * the thermal zone's "slave_agg_function" parameter. It can only be + * THERMAL_AGG_MAX or THERMAL_AGG_WEIGHTED_AVG. If THERMAL_AGG_MAX is + * used then the @temp holds the maximum temperature of all slave + * thermal zones. With THERMAL_AGG_WEIGHTED_AVG a weighted average of + * all temperatures is calculated. Each thermal zone's temperature is + * multiplied by its weight and the result is divided by the sum of + * all weights. If all weights are zero, the result is the average + * weight of the thermal zones. + * + * Return: 0 on success, -EINVAL if there are no slave thermal zones, + * -E* if thermal_zone_get_temp() fails for any of the slave thermal + * zones. + */ +static int get_subtz_temp(struct thermal_zone_device *tz, int *temp) +{ + struct thermal_zone_link *link; + int ret_temp, total_weight = 0; + bool all_weights_are_zero = false; + + if (list_empty(&tz->slave_tzs)) + return -EINVAL; + + if (tz->slave_agg_function == THERMAL_AGG_WEIGHTED_AVG) { + int total_instances = 0; + + list_for_each_entry(link, &tz->slave_tzs, node) { + total_weight += link->weight; + total_instances++; + } + + if (!total_weight) { + all_weights_are_zero = true; + total_weight = total_instances; + } else { + all_weights_are_zero = false; + } + + ret_temp = 0; + } else if (tz->slave_agg_function == THERMAL_AGG_MAX) { + ret_temp = INT_MIN; + } + + list_for_each_entry(link, &tz->slave_tzs, node) { + int this_temp, ret; + + ret = thermal_zone_get_temp(link->slave, &this_temp); + if (ret) + return ret; + + if (tz->slave_agg_function == THERMAL_AGG_MAX) { + if (this_temp > ret_temp) + ret_temp = this_temp; + } else if (tz->slave_agg_function == THERMAL_AGG_WEIGHTED_AVG) { + int weight = all_weights_are_zero ? 1 : link->weight; + + ret_temp += weight * this_temp; + } + } + + if (tz->slave_agg_function == THERMAL_AGG_WEIGHTED_AVG) + ret_temp /= total_weight; + + *temp = ret_temp; + return 0; +} + +/** * thermal_zone_get_temp() - returns the temperature of a thermal zone * @tz: a valid pointer to a struct thermal_zone_device * @temp: a valid pointer to where to store the resulting temperature. @@ -481,11 +569,22 @@ int thermal_zone_get_temp(struct thermal_zone_device *tz, int *temp) int crit_temp = INT_MAX; enum thermal_trip_type type; - if (!tz || IS_ERR(tz) || !tz->ops->get_temp) + if (!tz || IS_ERR(tz)) goto exit; + /* Avoid loops */ + if (tz->slave_tz_visited) + return -EDEADLK; + mutex_lock(&tz->lock); + tz->slave_tz_visited = true; + + if (!tz->ops->get_temp) { + ret = get_subtz_temp(tz, temp); + goto unlock; + } + ret = tz->ops->get_temp(tz, temp); if (IS_ENABLED(CONFIG_THERMAL_EMULATION) && tz->emul_temperature) { @@ -506,7 +605,9 @@ int thermal_zone_get_temp(struct thermal_zone_device *tz, int *temp) if (!ret && *temp < crit_temp) *temp = tz->emul_temperature; } - + +unlock: + tz->slave_tz_visited = false; mutex_unlock(&tz->lock); exit: return ret; @@ -540,9 +641,6 @@ void thermal_zone_device_update(struct thermal_zone_device *tz) { int count; - if (!tz->ops->get_temp) - return; - update_temperature(tz); for (count = 0; count < tz->trips; count++) @@ -1785,10 +1883,17 @@ struct thermal_zone_device *thermal_zone_device_register(const char *type, if (trips > 0 && (!ops->get_trip_type || !ops->get_trip_temp)) return ERR_PTR(-EINVAL); + if (tzp && (tzp->agg_func != THERMAL_AGG_MAX) && + (tzp->agg_func != THERMAL_AGG_WEIGHTED_AVG)) + return ERR_PTR(-EINVAL); + tz = kzalloc(sizeof(struct thermal_zone_device), GFP_KERNEL); if (!tz) return ERR_PTR(-ENOMEM); + if (tzp) + tz->slave_agg_function = tzp->agg_func; + INIT_LIST_HEAD(&tz->slave_tzs); INIT_LIST_HEAD(&tz->thermal_instances); idr_init(&tz->idr); mutex_init(&tz->lock); @@ -1921,6 +2026,7 @@ void thermal_zone_device_unregister(struct thermal_zone_device *tz) const struct thermal_zone_params *tzp; struct thermal_cooling_device *cdev; struct thermal_zone_device *pos = NULL; + struct thermal_zone_link *link, *tmp; if (!tz) return; @@ -1958,6 +2064,9 @@ void thermal_zone_device_unregister(struct thermal_zone_device *tz) mutex_unlock(&thermal_list_lock); + list_for_each_entry_safe(link, tmp, &tz->slave_tzs, node) + thermal_zone_del_subtz(tz, link->slave); + thermal_zone_device_set_polling(tz, 0); if (tz->type[0]) @@ -1980,6 +2089,97 @@ void thermal_zone_device_unregister(struct thermal_zone_device *tz) EXPORT_SYMBOL_GPL(thermal_zone_device_unregister); /** + * thermal_zone_add_subtz() - add a sub thermal zone to a thermal zone + * @tz: pointer to the master thermal zone + * @subtz: pointer to the slave thermal zone + * @weight: relative contribution of the sub thermal zone + * + * Add @subtz to the list of slave thermal zones of @tz. If @tz + * doesn't provide a get_temp() op, its temperature will be calculated + * as a combination of the temperatures of its sub thermal zones. The + * @weight is the relative contribution of this thermal zone when + * using THERMAL_AGG_WEIGHTED_AVG. Set @weight to + * THERMAL_WEIGHT_DEFAULT for all sub thermal zones to do a simple + * average. See get_sub_tz_temp() for more information on how the + * temperature for @tz is calculated. + * + * Return: 0 on success, -EINVAL if @tz or @subtz are not valid + * pointers, -EEXIST if the link already exists or -ENOMEM if we ran + * out of memory. + */ +int thermal_zone_add_subtz(struct thermal_zone_device *tz, + struct thermal_zone_device *subtz, int weight) +{ + int ret; + struct thermal_zone_link *link; + + if (IS_ERR_OR_NULL(tz) || IS_ERR_OR_NULL(subtz)) + return -EINVAL; + + mutex_lock(&tz->lock); + + list_for_each_entry(link, &tz->slave_tzs, node) { + if (link->slave == subtz) { + ret = -EEXIST; + goto unlock; + } + } + + link = kzalloc(sizeof(*link), GFP_KERNEL); + if (!link) { + ret = -ENOMEM; + goto unlock; + } + + link->slave = subtz; + link->weight = weight; + list_add_tail(&link->node, &tz->slave_tzs); + + ret = 0; + +unlock: + mutex_unlock(&tz->lock); + + return ret; +} + +/** + * thermal_zone_del_subtz() - delete a sub thermal zone from its master thermal zone + * @tz: pointer to the master thermal zone + * @subtz: pointer to the slave thermal zone + * + * Remove @subtz from the list of slave thermal zones of @tz. + * + * Return: 0 on success, -EINVAL if either thermal is invalid or if + * @subtz is not a slave of @tz. + */ +int thermal_zone_del_subtz(struct thermal_zone_device *tz, + struct thermal_zone_device *subtz) +{ + int ret = -EINVAL; + struct thermal_zone_link *link; + + if (IS_ERR_OR_NULL(tz) || IS_ERR_OR_NULL(subtz)) + return -EINVAL; + + mutex_lock(&tz->lock); + + list_for_each_entry(link, &tz->slave_tzs, node) { + if (link->slave == subtz) { + list_del(&link->node); + kfree(link); + + ret = 0; + break; + } + } + + mutex_unlock(&tz->lock); + + return ret; +} + +/** * thermal_zone_get_zone_by_name() - search for a zone and returns its ref * @name: thermal zone name to fetch the temperature * diff --git a/include/linux/thermal.h b/include/linux/thermal.h index 4014a59828fc..dc3d2ab77ab6 100644 --- a/include/linux/thermal.h +++ b/include/linux/thermal.h @@ -40,7 +40,7 @@ /* No upper/lower limit requirement */ #define THERMAL_NO_LIMIT ((u32)~0) -/* Default weight of a bound cooling device */ +/* Default weight for cooling devices and sub thermal zones */ #define THERMAL_WEIGHT_DEFAULT 0 /* Unit conversion macros */ @@ -89,6 +89,18 @@ enum thermal_trend { THERMAL_TREND_DROP_FULL, /* apply lowest cooling action */ }; +/** + * enum thermal_aggregation_function - aggregation function for sub thermal zones + * @THERMAL_AGG_MAX: calculate the maximum of all sub thermal zones + + * @THERMAL_AGG_WEIGHTED_AVG: calculate the weighted average of all + * sub thermal zones + */ +enum thermal_aggregation_function { + THERMAL_AGG_MAX, + THERMAL_AGG_WEIGHTED_AVG, +}; + struct thermal_zone_device_ops { int (*bind) (struct thermal_zone_device *, struct thermal_cooling_device *); @@ -170,6 +182,12 @@ struct thermal_attr { * @ops: operations this &thermal_zone_device supports * @tzp: thermal zone parameters * @governor: pointer to the governor for this thermal zone + * @slave_agg_function: aggretion function to calculate the + * temperature as a combination of the slave thermal zones + * of this thermal zone. See enum + * thermal_aggregation_function for valid values + * @slave_tzs: list of thermal zones that are a slave of this thermal zone + * @slave_tz_visited: used to detect loops in stacked thermal zones * @governor_data: private pointer for governor data * @thermal_instances: list of &struct thermal_instance of this thermal zone * @idr: &struct idr to generate unique id for this zone's cooling @@ -197,6 +215,9 @@ struct thermal_zone_device { struct thermal_zone_device_ops *ops; struct thermal_zone_params *tzp; struct thermal_governor *governor; + enum thermal_aggregation_function slave_agg_function; + struct list_head slave_tzs; + bool slave_tz_visited; void *governor_data; struct list_head thermal_instances; struct idr idr; @@ -311,6 +332,13 @@ struct thermal_zone_params { * Used by thermal zone drivers (default 0). */ int offset; + + /* + * aggregation function to use when calculating the + * temperature as a combination of multiple sub thermal + * zones + */ + enum thermal_aggregation_function agg_func; }; struct thermal_genl_event { @@ -405,6 +433,10 @@ struct thermal_cooling_device * thermal_of_cooling_device_register(struct device_node *np, char *, void *, const struct thermal_cooling_device_ops *); void thermal_cooling_device_unregister(struct thermal_cooling_device *); +int thermal_zone_add_subtz(struct thermal_zone_device *, + struct thermal_zone_device *, int); +int thermal_zone_del_subtz(struct thermal_zone_device *, + struct thermal_zone_device *); struct thermal_zone_device *thermal_zone_get_zone_by_name(const char *name); int thermal_zone_get_temp(struct thermal_zone_device *tz, int *temp); @@ -457,6 +489,13 @@ thermal_of_cooling_device_register(struct device_node *np, static inline void thermal_cooling_device_unregister( struct thermal_cooling_device *cdev) { } +static inline int thermal_zone_add_subtz(struct thermal_zone_device *tz, + struct thermal_zone_device *subtz, + int weight) +{ return -ENODEV; } +static inline int thermal_zone_del_subtz(struct thermal_zone_device *tz, + struct thermal_zone_device *subtz) +{ return -ENODEV; } static inline struct thermal_zone_device *thermal_zone_get_zone_by_name( const char *name) { return ERR_PTR(-ENODEV); }
Add the ability to stack thermal zones on top of each other, creating a hierarchy of thermal zones. Cc: Zhang Rui <rui.zhang@intel.com> Cc: Eduardo Valentin <edubezval@gmail.com> Signed-off-by: Javi Merino <javi.merino@arm.com> --- Documentation/thermal/sysfs-api.txt | 39 +++++++ drivers/thermal/thermal_core.c | 210 +++++++++++++++++++++++++++++++++++- include/linux/thermal.h | 41 ++++++- 3 files changed, 284 insertions(+), 6 deletions(-)