blaster4385/linux-IllusionX/drivers/thermal/gov_power_allocator.c, branch v6.12.10

thermal: gov_power_allocator: Return early in manage if trip_max is NULL

2024-07-04T11:35:50Z

Commit da781936e7c3 ("thermal: gov_power_allocator: Allow binding without trip points") allowed the governor to bind even when trip_max is NULL. This allows a NULL pointer dereference to happen in the manage callback. Add an early return to prevent it, since the governor is expected to not do anything in this case. Fixes: da781936e7c3 ("thermal: gov_power_allocator: Allow binding without trip points") Signed-off-by: Nícolas F. R. A. Prado Link: https://patch.msgid.link/20240702-power-allocator-null-trip-max-v1-1-47a60dc55414@collabora.com Cc: All applicable Signed-off-by: Rafael J. Wysocki

thermal: core: Move passive polling management to the core

2024-04-30T19:16:13Z

Passive polling is enabled by setting the 'passive' field in struct thermal_zone_device to a positive value so long as the 'passive_delay_jiffies' field is greater than zero. It causes the thermal core to actively check the thermal zone temperature periodically which in theory should be done after crossing a passive trip point on the way up in order to allow governors to react more rapidly to temperature changes and adjust mitigation more precisely. However, the 'passive' field in struct thermal_zone_device is currently managed by governors which is quite problematic. First of all, only two governors, Step-Wise and Power Allocator, update that field at all, so the other governors do not benefit from passive polling, although in principle they should. Moreover, if the zone governor is changed from, say, Step-Wise to Fair-Share after 'passive' has been incremented by the former, it is not going to be reset back to zero by the latter even if the zone temperature falls down below all passive trip points. For this reason, make handle_thermal_trip() increment 'passive' to enable passive polling for the given thermal zone whenever a passive trip point is crossed on the way up and decrement it whenever a passive trip point is crossed on the way down. Also remove the 'passive' field updates from governors and additionally clear it in thermal_zone_device_init() to prevent passive polling from being enabled after a system resume just beacuse it was enabled before suspending the system. Signed-off-by: Rafael J. Wysocki Reviewed-by: Lukasz Luba Tested-by: Lukasz Luba

thermal: gov_power_allocator: Eliminate a redundant variable

2024-04-23T18:39:50Z

Notice that the passive field in struct thermal_zone_device is not used by the Power Allocator governor itself and so the ordering of its updates with respect to allow_maximum_power() or allocate_power() does not matter. Accordingly, make power_allocator_manage() update that field right before returning, which allows the current value of it to be passed directly to allow_maximum_power() without using the additional update variable that can be dropped. Signed-off-by: Rafael J. Wysocki Reviewed-by: Lukasz Luba

thermal: gov_power_allocator: Use .manage() callback instead of .throttle()

2024-04-23T18:39:50Z

The Power Allocator governor really only wants to be called once per thermal zone update and it does a special check to skip the extra, from its perspective, invocations of the .throttle() callback. Make it use .manage() instead of .throttle(). Signed-off-by: Rafael J. Wysocki Reviewed-by: Lukasz Luba

thermal: core: Move threshold out of struct thermal_trip

2024-04-08T14:01:20Z

The threshold field in struct thermal_trip is only used internally by the thermal core and it is better to prevent drivers from misusing it. It also takes some space unnecessarily in the trip tables passed by drivers to the core during thermal zone registration. For this reason, introduce struct thermal_trip_desc as a wrapper around struct thermal_trip, move the threshold field directly into it and make the thermal core store struct thermal_trip_desc objects in the internal thermal zone trip tables. Adjust all of the code using trip tables in the thermal core accordingly. No intentional functional impact. Signed-off-by: Rafael J. Wysocki Reviewed-by: Lukasz Luba

thermal: gov_power_allocator: Allow binding without trip points

2024-04-03T14:32:15Z

IPA probe function was recently refactored to perform extra error checks and make sure the thermal zone has trip points necessary for the IPA operation. With this change, if a thermal zone is probed such that it has no trip points that IPA can use, IPA will fail and the TZ won't be created. This is the case if a platform defines a TZ without cooling devices and only with "hot"/"critical" trip points, often found on some Qualcomm devices [1]. Documentation across IPA code (notably get_governor_trips() kerneldoc) suggests that IPA is supposed to handle such TZ even if it won't actually do anything. This commit partially reverts the previous change to allow IPA to bind to such "empty" thermal zones. Fixes: e83747c2f8e3 ("thermal: gov_power_allocator: Set up trip points earlier") Link: arch/arm64/boot/dts/qcom/sc7180.dtsi#n4776 # [1] Signed-off-by: Nikita Travkin Reviewed-by: Lukasz Luba Signed-off-by: Rafael J. Wysocki

thermal: gov_power_allocator: Allow binding without cooling devices

2024-04-03T14:32:14Z

IPA was recently refactored to split out memory allocation into a separate funciton. That funciton was made to return -EINVAL if there is zero power_actors and thus no memory to allocate. This causes IPA to fail probing when the thermal zone has no attached cooling devices. Since cooling devices can attach after the thermal zone is created and the governer is attached to it, failing probe due to the lack of cooling devices is incorrect. Change the allocate_actors_buffer() to return success when there is no cooling devices present. Fixes: 912e97c67cc3 ("thermal: gov_power_allocator: Move memory allocation out of throttle()") Signed-off-by: Nikita Travkin Reviewed-by: Lukasz Luba Signed-off-by: Rafael J. Wysocki

thermal: gov_power_allocator: Avoid overwriting PID coefficients from setup time

2024-02-12T13:13:36Z

When the PID coefficients k_* are set via sysfs before the IPA algorithm is triggered then the coefficients would be overwritten after IPA throttle() is called. The old configuration values might be different than the new values estimated by the IPA internal algorithm. There might be a time delay when this overwriting happens. It depends on the thermal zone temperature value. The temperature value needs to cross the first trip point value then IPA algorithms start operating. Although, the PID coefficients setup time should not be affected or linked to any later operating phase and values must not be overwritten. This patch initializes params->sustainable_power when the governor binds to thermal zone to avoid overwriting k_*. The basic function won't be affected, as the k_* still can be estimated if the sustainable_power is modified. Signed-off-by: Di Shen Reviewed-by: Lukasz Luba Signed-off-by: Rafael J. Wysocki

thermal: gov_power_allocator: avoid inability to reset a cdev

2024-01-12T14:38:23Z

Commit 0952177f2a1f ("thermal/core/power_allocator: Update once cooling devices when temp is low") adds an update flag to avoid triggering a thermal event when there is no need, and the thermal cdev is updated once when the temperature is low. But when the trips are writable, and switch_on_temp is set to be a higher value, the cooling device state may not be reset to 0, because last_temperature is smaller than switch_on_temp. For example: First: switch_on_temp=70 control_temp=85; Then userspace change the trip_temp: switch_on_temp=45 control_temp=55 cur_temp=54 Then userspace reset the trip_temp: switch_on_temp=70 control_temp=85 cur_temp=57 last_temp=54 At this time, the cooling device state should be reset to 0. However, because cur_temp(57) < switch_on_temp(70) last_temp(54) < switch_on_temp(70) ----> update = false, update is false, the cooling device state can not be reset. Using the observation that tz->passive can also be regarded as the temperature status, set the update flag to the tz->passive value. When the temperature drops below switch_on for the first time, the states of cooling devices can be reset once, and tz->passive is updated to 0. In the next round, because tz->passive is 0, cdev->state will not be updated. By using the tz->passive value as the "update" flag, the issue above can be solved, and the cooling devices can be updated only once when the temperature is low. Fixes: 0952177f2a1f ("thermal/core/power_allocator: Update once cooling devices when temp is low") Cc: 5.13+ # 5.13+ Suggested-by: Wei Wang Signed-off-by: Di Shen Reviewed-by: Lukasz Luba [ rjw: Subject and changelog edits ] Signed-off-by: Rafael J. Wysocki

thermal: gov_power_allocator: Support new update callback of weights

2023-12-29T17:01:01Z

When the thermal instance's weight is updated from the sysfs the governor update_tz() callback is triggered. Implement proper reaction to this event in the IPA, which would save CPU cycles spent in throttle(). This will speed-up the main throttle() IPA function and clean it up a bit. Signed-off-by: Lukasz Luba Signed-off-by: Rafael J. Wysocki