kernel/linux.git/drivers/thermal/gov_power_allocator.c, branch v6.6.131

thermal: gov_power_allocator: avoid inability to reset a cdev

2024-02-01T00:19:10+00:00

[ Upstream commit e95fa7404716f6e25021e66067271a4ad8eb1486 ] 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 Signed-off-by: Sasha Levin

thermal: core: Store trip pointer in struct thermal_instance

2024-02-01T00:19:10+00:00

[ Upstream commit 2c7b4bfadef08cc0995c24a7b9eb120fe897165f ] Replace the integer trip number stored in struct thermal_instance with a pointer to the relevant trip and adjust the code using the structure in question accordingly. The main reason for making this change is to allow the trip point to cooling device binding code more straightforward, as illustrated by subsequent modifications of the ACPI thermal driver, but it also helps to clarify the overall design and allows the governor code overhead to be reduced (through subsequent modifications). The only case in which it adds complexity is trip_point_show() that needs to walk the trips[] table to find the index of the given trip point, but this is not a critical path and the interface that trip_point_show() belongs to is problematic anyway (for instance, it doesn't cover the case when the same cooling devices is associated with multiple trip points). This is a preliminary change and the affected code will be refined by a series of subsequent modifications of thermal governors, the core and the ACPI thermal driver. The general functionality is not expected to be affected by this change. Signed-off-by: Rafael J. Wysocki Reviewed-by: Daniel Lezcano Stable-dep-of: e95fa7404716 ("thermal: gov_power_allocator: avoid inability to reset a cdev") Signed-off-by: Sasha Levin

thermal/core: Relocate the traces definition in thermal directory

2023-04-01T18:51:45+00:00

The traces are exported but only local to the thermal core code. On the other side, the traces take the thermal zone device structure as argument, thus they have to rely on the exported thermal.h header file. As we want to move the structure to the private thermal core header, first we have to relocate those traces to the same place as many drivers do. Cc: Steven Rostedt Suggested-by: Steven Rostedt Signed-off-by: Daniel Lezcano Reviewed-by: Steven Rostedt (Google) Link: https://lore.kernel.org/r/20230307133735.90772-2-daniel.lezcano@linaro.org

thermal/core/governors: Use thermal_zone_get_trip() instead of ops functions

2023-01-06T13:14:47+00:00

The governors are using the ops->get_trip_* functions, Replace these calls with thermal_zone_get_trip(). Signed-off-by: Daniel Lezcano Reviewed-by: Zhang Rui Reviewed-by: Lukasz Luba # IPA Acked-by: Rafael J. Wysocki Link: https://lore.kernel.org/r/20221003092602.1323944-5-daniel.lezcano@linaro.org

thermal/core/power allocator: Remove a useless include

2022-12-14T14:25:40+00:00

This file does not use rcu, so there is no point in including . Remove it. Signed-off-by: Christophe JAILLET Reviewed-by: Lukasz Luba Link: https://lore.kernel.org/r/9adeec47cb5a8193016272d5c8bf936235c1711d.1669459337.git.christophe.jaillet@wanadoo.fr Signed-off-by: Daniel Lezcano

thermal/core: Move the thermal zone lock out of the governors

2022-08-17T12:09:39+00:00

All the governors throttling ops are taking/releasing the lock at the beginning and the end of the function. We can move the mutex to the throttling call site instead. Signed-off-by: Daniel Lezcano Link: https://lore.kernel.org/r/20220805153834.2510142-4-daniel.lezcano@linaro.org

thermal/governors: Group the thermal zone lock inside the throttle function

2022-08-17T12:09:39+00:00

The thermal zone lock is taken in the different places in the throttling path. At the first glance it does not hurt to move them at the beginning and the end of the 'throttle' function. That will allow a consolidation of the lock in the next following changes. Signed-off-by: Daniel Lezcano Link: https://lore.kernel.org/r/20220805153834.2510142-3-daniel.lezcano@linaro.org

thermal/core: Rename 'trips' to 'num_trips'

2022-07-28T15:29:56+00:00

In order to use thermal trips defined in the thermal structure, rename the 'trips' field to 'num_trips' to have the 'trips' field containing the thermal trip points. Cc: Alexandre Bailon Cc: Kevin Hilman Signed-off-by: Daniel Lezcano Link: https://lore.kernel.org/r/20220722200007.1839356-8-daniel.lezcano@linexp.org Signed-off-by: Daniel Lezcano

thermal/core/power allocator: Use the lockless __thermal_cdev_update() function

2021-04-22T21:51:32+00:00

Use the new helper function and avoid unnecessery second lock/unlock, which was present in old approach with thermal_cdev_update(). Signed-off-by: Lukasz Luba Signed-off-by: Daniel Lezcano Link: https://lore.kernel.org/r/20210422153624.6074-4-lukasz.luba@arm.com

thermal/core/power_allocator: Update once cooling devices when temp is low

2021-04-22T21:51:14+00:00

The cooling device state change generates an event, also when there is no need, because temperature is low and device is not throttled. Avoid to unnecessary update the cooling device which means also not sending event. The cooling device state has not changed because the temperature is still below the first activation trip point value, so we can do this. Add a tracking mechanism to make sure it updates cooling devices only once - when the temperature dropps below first trip point. Reported-by: Daniel Lezcano Signed-off-by: Lukasz Luba Signed-off-by: Daniel Lezcano Link: https://lore.kernel.org/r/20210422114308.29684-4-lukasz.luba@arm.com