Re: [PATCH v1 4/6] thermal: gov_power_allocator: Use trip pointers instead of trip indices

From: Rafael J. Wysocki
Date: Thu Oct 12 2023 - 12:36:42 EST

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On Thu, Oct 12, 2023 at 5:19 PM Daniel Lezcano
<daniel.lezcano@xxxxxxxxxx> wrote:
>
> On 06/10/2023 19:47, Rafael J. Wysocki wrote:
> > From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
> >
> > Modify the power allocator thermal governor to use trip pointers instead
> > of trip indices everywhere except for the power_allocator_throttle()
> > second argument that will be changed subsequently along with the
> > definition of the .throttle() governor callback.
> >
> > The general functionality is not expected to be changed.
> >
> > Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
> > ---
> > drivers/thermal/gov_power_allocator.c | 123 +++++++++++++---------------------
> > 1 file changed, 49 insertions(+), 74 deletions(-)
> >
> > Index: linux-pm/drivers/thermal/gov_power_allocator.c
> > ===================================================================
> > --- linux-pm.orig/drivers/thermal/gov_power_allocator.c
> > +++ linux-pm/drivers/thermal/gov_power_allocator.c
> > @@ -16,8 +16,6 @@
> >
> > #include "thermal_core.h"
> >
> > -#define INVALID_TRIP -1
> > -
> > #define FRAC_BITS 10
> > #define int_to_frac(x) ((x) << FRAC_BITS)
> > #define frac_to_int(x) ((x) >> FRAC_BITS)
> > @@ -55,23 +53,23 @@ static inline s64 div_frac(s64 x, s64 y)
> > * @err_integral: accumulated error in the PID controller.
> > * @prev_err: error in the previous iteration of the PID controller.
> > * Used to calculate the derivative term.
> > + * @sustainable_power: Sustainable power (heat) that this thermal zone can
> > + * dissipate
> > * @trip_switch_on: first passive trip point of the thermal zone. The
> > * governor switches on when this trip point is crossed.
> > * If the thermal zone only has one passive trip point,
> > - * @trip_switch_on should be INVALID_TRIP.
> > + * @trip_switch_on should be NULL.
> > * @trip_max_desired_temperature: last passive trip point of the thermal
> > * zone. The temperature we are
> > * controlling for.
> > - * @sustainable_power: Sustainable power (heat) that this thermal zone can
> > - * dissipate
> > */
> > struct power_allocator_params {
> > bool allocated_tzp;
> > s64 err_integral;
> > s32 prev_err;
> > - int trip_switch_on;
> > - int trip_max_desired_temperature;
> > u32 sustainable_power;
> > + const struct thermal_trip *trip_switch_on;
> > + const struct thermal_trip *trip_max_desired_temperature;
> > };
> >
> > /**
> > @@ -90,14 +88,12 @@ static u32 estimate_sustainable_power(st
> > u32 sustainable_power = 0;
> > struct thermal_instance *instance;
> > struct power_allocator_params *params = tz->governor_data;
> > - const struct thermal_trip *trip_max_desired_temperature =
> > - &tz->trips[params->trip_max_desired_temperature];
> >
> > list_for_each_entry(instance, &tz->thermal_instances, tz_node) {
> > struct thermal_cooling_device *cdev = instance->cdev;
> > u32 min_power;
> >
> > - if (instance->trip != trip_max_desired_temperature)
> > + if (instance->trip != params->trip_max_desired_temperature)
> > continue;
> >
> > if (!cdev_is_power_actor(cdev))
> > @@ -116,24 +112,23 @@ static u32 estimate_sustainable_power(st
> > * estimate_pid_constants() - Estimate the constants for the PID controller
> > * @tz: thermal zone for which to estimate the constants
> > * @sustainable_power: sustainable power for the thermal zone
> > - * @trip_switch_on: trip point number for the switch on temperature
> > + * @trip_switch_on: trip point for the switch on temperature
> > * @control_temp: target temperature for the power allocator governor
> > *
> > * This function is used to update the estimation of the PID
> > * controller constants in struct thermal_zone_parameters.
> > */
> > static void estimate_pid_constants(struct thermal_zone_device *tz,
> > - u32 sustainable_power, int trip_switch_on,
> > + u32 sustainable_power,
> > + const struct thermal_trip *trip_switch_on,
> > int control_temp)
> > {
> > - struct thermal_trip trip;
> > u32 temperature_threshold = control_temp;
> > int ret;
> > s32 k_i;
> >
> > - ret = __thermal_zone_get_trip(tz, trip_switch_on, &trip);
> > - if (!ret)
> > - temperature_threshold -= trip.temperature;
> > + if (trip_switch_on)
> > + temperature_threshold -= trip_switch_on->temperature;
> >
> > /*
> > * estimate_pid_constants() tries to find appropriate default
> > @@ -386,7 +381,7 @@ static int allocate_power(struct thermal
> > struct thermal_instance *instance;
> > struct power_allocator_params *params = tz->governor_data;
> > const struct thermal_trip *trip_max_desired_temperature =
> > - &tz->trips[params->trip_max_desired_temperature];
> > + params->trip_max_desired_temperature;
> > u32 *req_power, *max_power, *granted_power, *extra_actor_power;
> > u32 *weighted_req_power;
> > u32 total_req_power, max_allocatable_power, total_weighted_req_power;
> > @@ -496,7 +491,7 @@ static int allocate_power(struct thermal
> > }
> >
> > /**
> > - * get_governor_trips() - get the number of the two trip points that are key for this governor
> > + * get_governor_trips() - get the two trip points that are key for this governor
> > * @tz: thermal zone to operate on
> > * @params: pointer to private data for this governor
> > *
> > @@ -513,46 +508,36 @@ static int allocate_power(struct thermal
> > static void get_governor_trips(struct thermal_zone_device *tz,
> > struct power_allocator_params *params)
> > {
> > - int i, last_active, last_passive;
> > - bool found_first_passive;
> > -
> > - found_first_passive = false;
> > - last_active = INVALID_TRIP;
> > - last_passive = INVALID_TRIP;
> > -
> > - for (i = 0; i < tz->num_trips; i++) {
> > - struct thermal_trip trip;
> > - int ret;
> > -
> > - ret = __thermal_zone_get_trip(tz, i, &trip);
> > - if (ret) {
> > - dev_warn(&tz->device,
> > - "Failed to get trip point %d type: %d\n", i,
> > - ret);
> > - continue;
> > - }
> > -
> > - if (trip.type == THERMAL_TRIP_PASSIVE) {
> > - if (!found_first_passive) {
> > - params->trip_switch_on = i;
> > - found_first_passive = true;
> > - } else {
> > - last_passive = i;
> > + const struct thermal_trip *first_passive = NULL;
> > + const struct thermal_trip *last_passive = NULL;
> > + const struct thermal_trip *last_active = NULL;
> > + const struct thermal_trip *trip;
> > +
> > + for_each_trip(tz, trip) {
> > + switch (trip->type) {
> > + case THERMAL_TRIP_PASSIVE:
> > + if (!first_passive) {
> > + first_passive = trip;
> > + break;
> > }
> > - } else if (trip.type == THERMAL_TRIP_ACTIVE) {
> > - last_active = i;
> > - } else {
> > + last_passive = trip;
> > + break;
> > + case THERMAL_TRIP_ACTIVE:
> > + last_active = trip;
> > + break;
> > + default:
> > break;
> > }
> > }
> >
> > - if (last_passive != INVALID_TRIP) {
> > + if (last_passive) {
> > + params->trip_switch_on = first_passive;
> > params->trip_max_desired_temperature = last_passive;
> > - } else if (found_first_passive) {
> > - params->trip_max_desired_temperature = params->trip_switch_on;
> > - params->trip_switch_on = INVALID_TRIP;
> > + } else if (first_passive) {
> > + params->trip_switch_on = NULL;
> > + params->trip_max_desired_temperature = first_passive;
> > } else {
> > - params->trip_switch_on = INVALID_TRIP;
> > + params->trip_switch_on = NULL;
> > params->trip_max_desired_temperature = last_active;
> > }
> > }
> > @@ -567,14 +552,12 @@ static void allow_maximum_power(struct t
> > {
> > struct thermal_instance *instance;
> > struct power_allocator_params *params = tz->governor_data;
> > - const struct thermal_trip *trip_max_desired_temperature =
> > - &tz->trips[params->trip_max_desired_temperature];
> > u32 req_power;
> >
> > list_for_each_entry(instance, &tz->thermal_instances, tz_node) {
> > struct thermal_cooling_device *cdev = instance->cdev;
> >
> > - if ((instance->trip != trip_max_desired_temperature) ||
> > + if (instance->trip != params->trip_max_desired_temperature ||
> > (!cdev_is_power_actor(instance->cdev)))
> > continue;
> >
> > @@ -636,7 +619,6 @@ static int power_allocator_bind(struct t
> > {
> > int ret;
> > struct power_allocator_params *params;
> > - struct thermal_trip trip;
> >
> > ret = check_power_actors(tz);
> > if (ret)
> > @@ -662,12 +644,13 @@ static int power_allocator_bind(struct t
> > get_governor_trips(tz, params);
> >
> > if (tz->num_trips > 0) {
>
> Maybe this test can go away because if (trip) is true below, then
> logically (tz->num_trips > 0) ?

Yes, it can go away.

> > - ret = __thermal_zone_get_trip(tz, params->trip_max_desired_temperature,
> > - &trip);
> > - if (!ret)
> > + const struct thermal_trip *trip;
> > +
> > + trip = params->trip_max_desired_temperature;
> > + if (trip)
> > estimate_pid_constants(tz, tz->tzp->sustainable_power,
> > params->trip_switch_on,
> > - trip.temperature);
> > + trip->temperature);
> > }
> >
> > reset_pid_controller(params);
> > @@ -697,11 +680,10 @@ static void power_allocator_unbind(struc
> > tz->governor_data = NULL;
> > }
> >
> > -static int power_allocator_throttle(struct thermal_zone_device *tz, int trip_id)
> > +static int power_allocator_throttle(struct thermal_zone_device *tz, int trip_index)
> > {
> > struct power_allocator_params *params = tz->governor_data;
> > - struct thermal_trip trip;
> > - int ret;
> > + const struct thermal_trip *trip = &tz->trips[trip_index];
> > bool update;
> >
> > lockdep_assert_held(&tz->lock);
> > @@ -710,12 +692,12 @@ static int power_allocator_throttle(stru
> > * We get called for every trip point but we only need to do
> > * our calculations once
> > */
> > - if (trip_id != params->trip_max_desired_temperature)
> > + if (trip != params->trip_max_desired_temperature)
> > return 0;
> >
> > - ret = __thermal_zone_get_trip(tz, params->trip_switch_on, &trip);
> > - if (!ret && (tz->temperature < trip.temperature)) {
> > - update = (tz->last_temperature >= trip.temperature);
> > + trip = params->trip_switch_on;
> > + if (trip && tz->temperature < trip->temperature) {
> > + update = tz->last_temperature >= trip->temperature;
> > tz->passive = 0;
> > reset_pid_controller(params);
> > allow_maximum_power(tz, update);
> > @@ -724,14 +706,7 @@ static int power_allocator_throttle(stru
> >
> > tz->passive = 1;
> >
> > - ret = __thermal_zone_get_trip(tz, params->trip_max_desired_temperature, &trip);
> > - if (ret) {
> > - dev_warn(&tz->device, "Failed to get the maximum desired temperature: %d\n",
> > - ret);
> > - return ret;
> > - }
> > -
> > - return allocate_power(tz, trip.temperature);
> > + return allocate_power(tz, params->trip_max_desired_temperature->temperature);
> > }
> >
> > static struct thermal_governor thermal_gov_power_allocator = {
> >
> >
> >
>
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Next message: Geoff Levand: "Re: [PATCH] [RFC] wireless: move obsolete drivers to staging"
Previous message: Waiman Long: "Re: [PATCH] cgroup/cpuset: Change nr_deadline_tasks to an atomic_t value"
In reply to: Daniel Lezcano: "Re: [PATCH v1 4/6] thermal: gov_power_allocator: Use trip pointers instead of trip indices"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]