384 Commits

Author SHA1 Message Date
Rafael J. Wysocki
43bac1026f thermal: core: Relocate thermal zone initialization routine
Move thermal_zone_device_init() along with thermal_zone_device_check()
closer to the callers of the former, where they fit better together.

No functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
Link: https://patch.msgid.link/1906685.CQOukoFCf9@rjwysocki.net
2024-10-24 17:15:07 +02:00
Rafael J. Wysocki
6d5537d40c thermal: core: Use trip lists for trip crossing detection
Modify the thermal core to use three lists of trip points:

 trips_high, containing trips with thresholds strictly above the current
 thermal zone temperature,

 trips_reached, containing trips with thresholds at or below the current
 zone temperature,

 trips_invalid, containing trips with temperature equal to
 THERMAL_ZONE_INVALID,

where the first two lists are always sorted by the current trip
threshold.

For each trip in trips_high, there is no mitigation under way and
the trip threshold is equal to its temperature.  In turn, for each
trip in trips_reached, there is mitigation under way and the trip
threshold is equal to its low temperature.  The trips in trips_invalid,
of course, need not be taken into consideration.

The idea is to make __thermal_zone_device_update() walk trips_high and
trips_reached instead of walking the entire table of trip points in a
thermal zone.  Usually, it will only need to walk a few entries in one
of the lists and check one entry in the other list, depending on the
direction of the zone temperature changes, because crossing many trips
by the zone temperature in one go between two consecutive temperature
checks should be unlikely (if it occurs often, the thermal zone
temperature should probably be checked more often either or there
are too many trips).

This also helps to eliminate one temporary trip list used for trip
crossing notification (only one temporary list is needed for this
purpose instead of two) and the remaining temporary list may be sorted
by the current trip threshold value, like the trips_reached list, so
the additional notify_temp field in struct thermal_trip_desc is not
necessary any more.

Moreover, since the trips_reached and trips_high lists are sorted,
the "low" and "high" values needed by thermal_zone_set_trips() can be
determined in a straightforward way by looking at one end of each list.

Of course, additional work is needed in some places in order to
maintain the ordering of the lists, but it is limited to situations
that should be rare, like updating a trip point temperature or
hysteresis, thermal zone initialization, or system resume.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
Link: https://patch.msgid.link/2003443.usQuhbGJ8B@rjwysocki.net
[ rjw: Added a comment to thermal_zone_handle_trips() ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2024-10-24 17:15:07 +02:00
Rafael J. Wysocki
a44b5e39e4 thermal: core: Eliminate thermal_zone_trip_down()
Since thermal_zone_set_trip_temp() is now located in the same file
as thermal_trip_crossed(), it can invoke the latter directly without
using the thermal_zone_trip_down() wrapper that has no other users.

Update thermal_zone_set_trip_temp() accordingly and drop
thermal_zone_trip_down().

No functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
Link: https://patch.msgid.link/1807510.VLH7GnMWUR@rjwysocki.net
2024-10-24 17:15:07 +02:00
Rafael J. Wysocki
e654a0c58d thermal: core: Relocate functions that update trip points
In preparation for subsequent changes, move two functions used
for updating trip points, thermal_zone_set_trip_temp() and
thermal_zone_set_trip_hyst(), to thermal_core.c.

No functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
Link: https://patch.msgid.link/3248558.5fSG56mABF@rjwysocki.net
2024-10-24 17:15:07 +02:00
Rafael J. Wysocki
72fb849f77 thermal: core: Move some trip processing to thermal_trip_crossed()
Notice that some processing related to trip point crossing carried out
in handle_thermal_trip() and thermal_zone_set_trip_temp() may as well
be done in thermal_trip_crossed(), which allows code duplication to be
reduced, so change the code accordingly.

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
Link: https://patch.msgid.link/1982859.PYKUYFuaPT@rjwysocki.net
2024-10-24 17:15:07 +02:00
Rafael J. Wysocki
db0a46b600 thermal: core: Pass trip descriptor to thermal_trip_crossed()
In preparation for subsequent changes, modify thermal_trip_crossed()
to take a trip descriptor pointer instead of a pointer to struct
thermal_trip and propagate this change to thermal_zone_trip_down().

No functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
Link: https://patch.msgid.link/10547668.nUPlyArG6x@rjwysocki.net
2024-10-24 17:15:06 +02:00
Rafael J. Wysocki
e254ec292f thermal: core: Rearrange __thermal_zone_device_update()
In preparation for subsequent changes, move the invocations of
thermal_thresholds_handle() and thermal_zone_set_trips() in
__thermal_zone_device_update() after the processing of the
temporary trip lists.

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
Link: https://patch.msgid.link/3323276.44csPzL39Z@rjwysocki.net
2024-10-24 17:15:06 +02:00
Rafael J. Wysocki
ca70d55ab0 thermal: core: Prepare for moving trips between sorted lists
Subsequently, trips will be moved between sorted lists in multiple
places, so replace add_trip_to_sorted_list() with an analogous
function, move_trip_to_sorted_list(), that will move a given trip
to a given sorted list.

To allow list_del() used in the new function to work, initialize the
list_node fields in trip descriptors where applicable so they are
always valid.

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
Link: https://patch.msgid.link/2960197.e9J7NaK4W3@rjwysocki.net
2024-10-24 17:15:06 +02:00
Rafael J. Wysocki
bd32eacd95 thermal: core: Rename trip list node in struct thermal_trip_desc
Since the list node field in struct thermal_trip_desc is going to be
used for purposes other than trip crossing notification, rename it
to list_node.

No functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
Link: https://patch.msgid.link/2201558.irdbgypaU6@rjwysocki.net
2024-10-24 17:15:06 +02:00
Rafael J. Wysocki
c12629f832 thermal: core: Build sorted lists instead of sorting them later
Since it is not expected that multiple trip points will be crossed
in one go very often (if this happens, there are too many trip points
in the given thermal zone or they are checked too rarely), quite likely
it is more efficient to build a sorted list of crossed trip points than
to put them on an unsorted list and sort it later.

Moreover, trip points are often sorted in ascending temperature order
during thermal zone registration, so building a sorted list out of
them is quite straightforward and relatively inexpensive.

Accordingly, make handle_thermal_trip() maintain list ordering when
adding trip points to the lists and get rid of separate list sorting
in __thermal_zone_device_update().

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
Link: https://patch.msgid.link/4930656.GXAFRqVoOG@rjwysocki.net
2024-10-24 17:15:06 +02:00
Rafael J. Wysocki
dfa245f512 thermal: core: Manage thermal_governor_lock using a mutex guard
Switch over the thermal core to using a mutex guard for
thermal_governor_lock management.

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://patch.msgid.link/3679429.R56niFO833@rjwysocki.net
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
2024-10-24 14:48:42 +02:00
Rafael J. Wysocki
af73d53e97 thermal: core: Separate thermal zone governor initialization
In preparation for a subsequent change that will switch over the thermal
core to using a mutex guard for managing thermal_governor_lock, move
the code running in thermal_zone_device_register_with_trips() under that
lock into a separate function called thermal_zone_init_governor().

While at it, drop a useless comment.

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://patch.msgid.link/4408795.ejJDZkT8p0@rjwysocki.net
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
2024-10-24 14:48:42 +02:00
Rafael J. Wysocki
a5a98a786e thermal: core: Add and use cooling device guard
Add and use a special guard for cooling devices.

This allows quite a few error code paths to be simplified among
other things and brings in code size reduction for a good measure.

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://patch.msgid.link/5837621.DvuYhMxLoT@rjwysocki.net
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
2024-10-24 14:48:23 +02:00
Rafael J. Wysocki
c690dce5dc thermal: core: Introduce thermal_instance_delete()
It is not necessary to walk the thermal_instances list in a trip
descriptor under a cooling device lock, so acquire that lock only
for deleting the given thermal instance from the list of thermal
instances in the given cdev.

Moreover, in analogy with the previous change that introduced
thermal_instance_add(), put the code deleting the given thermal
instance from the lists it is on into a separate new function
called thermal_instance_delete().

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://patch.msgid.link/3275745.5fSG56mABF@rjwysocki.net
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
2024-10-23 11:57:04 +02:00
Rafael J. Wysocki
6d153f52cc thermal: core: Introduce thermal_instance_add()
To reduce the number of redundant result checks in
thermal_bind_cdev_to_trip() and make the code in it easier to
follow, move some of it to a new function called thermal_instance_add()
and make thermal_bind_cdev_to_trip() invoke that function.

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://patch.msgid.link/3618899.iIbC2pHGDl@rjwysocki.net
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
2024-10-23 11:56:57 +02:00
Rafael J. Wysocki
33eab804d6 thermal: core: Call thermal_governor_update_tz() outside of cdev lock
Holding a cooling device lock under thermal_governor_update_tz() is not
necessary and it may cause lockdep to complain if any governor's
.update_tz() callback attempts to lock a cdev.

For this reason, move the thermal_governor_update_tz() calls in
thermal_bind_cdev_to_trip() and thermal_unbind_cdev_from_trip() from
under the cdev lock.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://patch.msgid.link/7749552.EvYhyI6sBW@rjwysocki.net
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
2024-10-23 11:56:49 +02:00
Rafael J. Wysocki
d1c8aa2a5c thermal: core: Manage thermal_list_lock using a mutex guard
Switch over the thermal core to using a mutex guard for
thermal_list_lock management.

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://patch.msgid.link/2010397.PYKUYFuaPT@rjwysocki.net
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
2024-10-23 11:56:40 +02:00
Rafael J. Wysocki
6f60ae7221 thermal: core: Separate code running under thermal_list_lock
To prepare for a subsequent change that will switch over the thermal
core to using a mutex guard for thermal_list_lock management, move the
code running under thermal_list_lock during the initialization and
unregistration of cooling devices into separate functions.

While at it, drop some comments that do not add value.

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://patch.msgid.link/10572828.nUPlyArG6x@rjwysocki.net
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
2024-10-23 11:56:33 +02:00
Rafael J. Wysocki
57f076664c thermal: core: Add and use a reverse thermal zone guard
Add a guard for unlocking a locked thermal zone temporarily and use it
in thermal_zone_pm_prepare().

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://patch.msgid.link/3344086.aeNJFYEL58@rjwysocki.net
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
2024-10-23 11:56:27 +02:00
Rafael J. Wysocki
cba00d16a2 thermal: core: Add and use thermal zone guard
Add and use a guard for thermal zone locking.

This allows quite a few error code paths to be simplified among
other things and brings in a noticeable code size reduction for
a good measure.

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://patch.msgid.link/1930069.tdWV9SEqCh@rjwysocki.net
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
2024-10-23 11:56:19 +02:00
Rafael J. Wysocki
17f76be51c thermal: core: Pass trip descriptors to trip bind/unbind functions
The code is somewhat cleaner if struct thermal_trip_desc pointers are
passed to thermal_bind_cdev_to_trip(), thermal_unbind_cdev_from_trip(),
and print_bind_err_msg() instead of struct thermal_trip pointers, so
modify it accordingly.

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://patch.msgid.link/2246211.NgBsaNRSFp@rjwysocki.net
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
2024-10-22 12:08:11 +02:00
Rafael J. Wysocki
0dc23567c2 thermal: core: Move lists of thermal instances to trip descriptors
In almost all places where a thermal zone's list of thermal instances
is walked, there is a check to match a specific trip point and it is
walked in vain whenever there are no cooling devices associated with
the given trip.

To address this, store the lists of thermal instances in trip point
descriptors instead of storing them in thermal zones and adjust all
code using those lists accordingly.

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://patch.msgid.link/5522726.Sb9uPGUboI@rjwysocki.net
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
2024-10-22 12:08:03 +02:00
Rafael J. Wysocki
ee879a5ea3 thermal: core: Drop need_update field from struct thermal_zone_device
After previous changes, the need_update field in struct thermal_zone_device
is only set and never read, so drop it.

No functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://patch.msgid.link/2495061.jE0xQCEvom@rjwysocki.net
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
2024-10-22 12:07:54 +02:00
Rafael J. Wysocki
c4cd42ebd3 thermal: core: Update thermal zones after cooling device binding
If a new cooling device is registered and it is bound to at least one
trip point in a given thermal zone, that thermal zone needs to be
updated via __thermal_zone_device_update().

Instead of doing this with the help of the need_update atomic field in
struct thermal_zone_device, which is not particularly straightforward,
make __thermal_zone_cdev_bind() return a bool value indicating whether
or not the given thermal zone needs to be updated because a new cooling
device has been bound to it and update thermal_zone_cdev_bind() to
call __thermal_zone_device_update() when this value is "true".

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://patch.msgid.link/2226302.Icojqenx9y@rjwysocki.net
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
2024-10-22 12:07:47 +02:00
Rafael J. Wysocki
fa4f9c9679 thermal: core: Consolidate thermal zone locking in the exit path
In analogy with a previous change in the thermal zone initialization
path, to avoid acquiring the thermal zone lock and releasing it multiple
times back and forth unnecessarily, move all of the code running under
thermal_list_lock in thermal_zone_device_unregister() into a new
function called thermal_zone_exit() and make the latter acquire the
thermal zone lock only once and release it along with thermal_list_lock.

For this purpose, provide an "unlocked" variant of
thermal_zone_cdev_unbind() to be called by thermal_zone_exit() under the
thermal zone lock.

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://patch.msgid.link/1963152.taCxCBeP46@rjwysocki.net
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
2024-10-22 12:07:40 +02:00
Rafael J. Wysocki
1dae3e70b4 thermal: core: Mark thermal zones as exiting before unregistration
In analogy with a previous change in the thermal zone registration code
path, to ensure that __thermal_zone_device_update() will return early
for thermal zones that are going away, introduce a thermal zone state
flag representing the "exit" state and set it while deleting the thermal
zone from thermal_tz_list.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://patch.msgid.link/4394176.ejJDZkT8p0@rjwysocki.net
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
2024-10-22 12:07:33 +02:00
Rafael J. Wysocki
d07700b474 thermal: core: Consolidate thermal zone locking during initialization
The part of thermal zone initialization carried out under
thermal_list_lock acquires the thermal zone lock and releases it
multiple times back and forth which is not really necessary.

Instead of doing this, make it acquire the thermal zone lock once after
acquiring thermal_list_lock and release it along with that lock.

For this purpose, move all of the code in question to
thermal_zone_init_complete() introduced previously and provide an
"unlocked" variant of thermal_zone_cdev_bind() to be invoked from
there.

Also notice that a thermal zone does not need to be added to
thermal_tz_list under its own lock, so make the new code acquire
the thermal zone lock after adding it to the list.

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://patch.msgid.link/1920382.CQOukoFCf9@rjwysocki.net
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
[ rjw: Rebase on top of recent thermal core changes ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2024-10-22 12:07:15 +02:00
Rafael J. Wysocki
cdf771ab47 thermal: core: Fix race between zone registration and system suspend
If the registration of a thermal zone takes place at the time when
system suspend is started, thermal_pm_notify() can run before the new
thermal zone is added to thermal_tz_list and its "suspended" flag will
not be set.  Consequently, if __thermal_zone_device_update() is called
for that thermal zone, it will not return early as expected which may
cause some destructive interference with the system suspend or resume
flow to occur.

To avoid that, make thermal_zone_init_complete() introduced previously
set the "suspended" flag for new thermal zones if it runs during system
suspend or resume.

Fixes: 4e814173a8c4 ("thermal: core: Fix thermal zone suspend-resume synchronization")
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://patch.msgid.link/8490245.NyiUUSuA9g@rjwysocki.net
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
2024-10-22 12:07:08 +02:00
Rafael J. Wysocki
7837fa8115 thermal: core: Mark thermal zones as initializing to start with
After thermal_zone_device_register_with_trips() has called
device_register() and it has registered the new thermal zone device
with the driver core, user space may access its sysfs attributes and,
among other things, it may enable the thermal zone before it is ready.

To address this, introduce a new thermal zone state flag for
initialization and set it before calling device_register() in
thermal_zone_device_register_with_trips().  This causes
__thermal_zone_device_update() to return early until the new flag
is cleared.

To clear it when the thermal zone is ready, introduce a new
function called thermal_zone_init_complete() that will also invoke
__thermal_zone_device_update() after clearing that flag (both under the
thernal zone lock) and make thermal_zone_device_register_with_trips()
call the new function instead of checking need_update and calling
thermal_zone_device_update() when it is set.

After this change, if user space enables the thermal zone prematurely,
__thermal_zone_device_update() will return early for it until
thermal_zone_init_complete() is called.  In turn, if the thermal zone
is not enabled by user space before thermal_zone_init_complete() is
called, the __thermal_zone_device_update() call in it will return early
because the thermal zone has not been enabled yet, but that function
will be invoked again by thermal_zone_device_set_mode() when the thermal
zone is enabled and it will not return early this time.

The checking of need_update is not necessary any more because the
__thermal_zone_device_update() calls potentially triggered by cooling
device binding take place before calling thermal_zone_init_complete(),
so they all will return early, which means that
thermal_zone_init_complete() must call __thermal_zone_device_update()
in case the thermal zone is enabled prematurely by user space.

Fixes: 203d3d4aa482 ("the generic thermal sysfs driver")
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://patch.msgid.link/9360231.CDJkKcVGEf@rjwysocki.net
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
2024-10-22 12:06:58 +02:00
Rafael J. Wysocki
26c9ab8090 thermal: core: Represent suspend-related thermal zone flags as bits
Instead of using two separate fields in struct thermal_zone_device for
representing flags related to thermal zone suspend, represent them
explicitly as bits in one u8 "state" field.

Subsequently, that field will be used for addressing race conditions
related to thermal zone initialization and exit.

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://patch.msgid.link/7733910.EvYhyI6sBW@rjwysocki.net
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
2024-10-22 12:06:52 +02:00
Rafael J. Wysocki
7ddca58857 thermal: core: Rearrange PM notification code
Move the code run for each thermal zone by the thermal PM notify
handler to separate functions.

This will help to make some subsequent changes look somewhat more
straightforward, among other things.

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://patch.msgid.link/2299090.iZASKD2KPV@rjwysocki.net
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
2024-10-22 12:06:45 +02:00
Rafael J. Wysocki
662f920f7e thermal: core: Initialize thermal zones before registering them
Since user space can start interacting with a new thermal zone as soon
as device_register() called by thermal_zone_device_register_with_trips()
returns, it is better to initialize the thermal zone before calling
device_register() on it.

Fixes: d0df264fbd3c ("thermal/core: Remove pointless thermal_zone_device_reset() function")
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://patch.msgid.link/3336146.44csPzL39Z@rjwysocki.net
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
2024-10-22 12:06:06 +02:00
Daniel Lezcano
85ee9449f7 thermal: core: Connect the threshold with the core
Initialize, de-initialize and handle the threshold in the same place
than the trip points.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://patch.msgid.link/20240923100005.2532430-3-daniel.lezcano@linaro.org
[ rjw: Subject edit ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2024-10-10 23:33:37 +02:00
Rafael J. Wysocki
827a07525c thermal: core: Free tzp copy along with the thermal zone
The object pointed to by tz->tzp may still be accessed after being
freed in thermal_zone_device_unregister(), so move the freeing of it
to the point after the removal completion has been completed at which
it cannot be accessed any more.

Fixes: 3d439b1a2ad3 ("thermal/core: Alloc-copy-free the thermal zone parameters structure")
Cc: 6.8+ <stable@vger.kernel.org> # 6.8+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
Link: https://patch.msgid.link/4623516.LvFx2qVVIh@rjwysocki.net
2024-10-04 19:05:08 +02:00
Rafael J. Wysocki
a42a5839f4 thermal: core: Reference count the zone in thermal_zone_get_by_id()
There are places in the thermal netlink code where nothing prevents
the thermal zone object from going away while being accessed after it
has been returned by thermal_zone_get_by_id().

To address this, make thermal_zone_get_by_id() get a reference on the
thermal zone device object to be returned with the help of get_device(),
under thermal_list_lock, and adjust all of its callers to this change
with the help of the cleanup.h infrastructure.

Fixes: 1ce50e7d408e ("thermal: core: genetlink support for events/cmd/sampling")
Cc: 6.8+ <stable@vger.kernel.org> # 6.8+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
Link: https://patch.msgid.link/6112242.lOV4Wx5bFT@rjwysocki.net
2024-10-04 19:05:08 +02:00
Rafael J. Wysocki
54fccad63e thermal: core: Drop thermal_zone_device_is_enabled()
There are only two callers of thermal_zone_device_is_enabled()
and one of them call is under the zone lock and the other one uses
lockdep_assert_held() on that lock.  Thus the lockdep_assert_held()
in thermal_zone_device_is_enabled() is redundant and it could be
dropped, but then the function would merely become a wrapper around
a simple tz->mode check that is more convenient to do directly.

Accordingly, drop thermal_zone_device_is_enabled() altogether and update
its callers to check tz->mode directly as appropriate.

While at it, combine the tz->mode and tz->suspended checks in
__thermal_zone_device_update() because they are of a similar category
and if any of them evaluates to "true", the outcome is the same.

No intentinal functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://patch.msgid.link/9353673.CDJkKcVGEf@rjwysocki.net
2024-09-05 12:33:24 +02:00
Rafael J. Wysocki
3c3ee53df4 thermal: core: Check passive delay in monitor_thermal_zone()
The only case in which thermal_zone_device_set_polling() is called
with its second argument equal to zero is when passive cooling is
under way and passive_delay_jiffies is 0, which only happens when
the given thermal zone is not polled at all.

If monitor_thermal_zone() is modified to check passive_delay_jiffies
directly, the check of the thermal_zone_device_set_polling() second
argument against 0 can be dropped and a passive_delay check can be
dropped from thermal_zone_device_register_with_trips(), so change the
code accordingly.

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://patch.msgid.link/2004353.PYKUYFuaPT@rjwysocki.net
2024-09-05 12:33:21 +02:00
Rafael J. Wysocki
fcfacd544b thermal: core: Drop dead code from monitor_thermal_zone()
Since monitor_thermal_zone() is only called when the given thermal zone
has been enabled, as per the thermal_zone_device_is_enabled() check in
__thermal_zone_device_update(), the tz->mode check in it always
evaluates to "false" and the thermal_zone_device_set_polling()
invocation depending on it is dead code, so drop it.

No functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://patch.msgid.link/10547425.nUPlyArG6x@rjwysocki.net
2024-09-05 12:33:18 +02:00
Rafael J. Wysocki
49029b507e thermal: core: Drop redundant lockdep_assert_held()
Along the lines of commit 24aad192c671 ("thermal: core: Drop
redundant checks from thermal_bind_cdev_to_trip()") notice that
thermal_unbind_cdev_from_trip() is only called by
thermal_zone_cdev_unbind() under the thermal zone lock, so it
need not use lockdep_assert_held() for that lock.

No functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://patch.msgid.link/3341369.44csPzL39Z@rjwysocki.net
2024-09-05 12:33:15 +02:00
Rafael J. Wysocki
e9654659fe thermal: core: Drop tz field from struct thermal_instance
After recent changes, it is only used for printing a debug message
in __thermal_cdev_update() which arguably is not worth preserving.

Drop it along with the dev_dbg() statement using it.

Link: https://lore.kernel.org/linux-pm/4a8d8f5a-122d-4c26-b8d6-76a65e42216b@linaro.org
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://patch.msgid.link/4934182.GXAFRqVoOG@rjwysocki.net
2024-08-23 15:56:29 +02:00
Rafael J. Wysocki
24aad192c6 thermal: core: Drop redundant checks from thermal_bind_cdev_to_trip()
Since thermal_bind_cdev_to_trip() is only called by
thermal_zone_cdev_binding() under the thermal zone lock and the latter
is only called by thermal_zone_device_register_with_trips() and
__thermal_cooling_device_register(), under thermal_list_lock in both
cases, both lockdep_assert_held() assertions can be dropped from it.

Moreover, in both cases thermal_zone_cdev_binding() is called after
both tz and cdev have been added to the global lists of thermal zones
and cooling device, respectively, so the check against their list nodes
in thermal_bind_cdev_to_trip() is redundant and can be dropped either.

Link: https://lore.kernel.org/linux-pm/CAJZ5v0jwkc2PB+osSkkYF9vJ1Vpp3MFE=cGQmQ2Xzjb3yjVfJg@mail.gmail.com/
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://patch.msgid.link/4607540.LvFx2qVVIh@rjwysocki.net
2024-08-23 15:56:29 +02:00
Rafael J. Wysocki
91d7ed957e thermal: core: Rename cdev-to-thermal-zone bind/unbind functions
Rename thermal_zone_cdev_binding() and thermal_zone_cdev_unbinding()
to thermal_zone_cdev_bind() and thermal_zone_cdev_unbind(), respectively,
to make the naming more consistent with the rest of the code.

No functional impact.

Link: https://lore.kernel.org/linux-pm/19beefd9-d3f9-4d43-a45d-d241996de2d0@linaro.org/
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://patch.msgid.link/6093162.lOV4Wx5bFT@rjwysocki.net
2024-08-23 15:56:29 +02:00
Rafael J. Wysocki
8144dbe68c thermal: core: Fix rounding of delay jiffies
Using round_jiffies() in thermal_set_delay_jiffies() is invalid because
its argument should be time in the future in absolute jiffies and it
computes the result with respect to the current jiffies value at the
invocation time.  Fortunately, in the majority of cases it does not
make any difference due to the time_is_after_jiffies() check in
round_jiffies_common().

While using round_jiffies_relative() instead of round_jiffies() might
reflect the intent a bit better, it still would not be defensible
because that function should be called when the timer is about to be
set and it is not suitable for pre-computation of delay values.

Accordingly, drop thermal_set_delay_jiffies() altogether, simply
convert polling_delay and passive_delay to jiffies during thermal
zone initialization and make thermal_zone_device_set_polling() call
round_jiffies_relative() on the delay if it is greather than 1 second.

Fixes: 17d399cd9c89 ("thermal/core: Precompute the delays from msecs to jiffies")
Fixes: e5f2cda61d06 ("thermal/core: Move thermal_set_delay_jiffies to static")
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://patch.msgid.link/1994438.PYKUYFuaPT@rjwysocki.net
2024-08-23 15:53:53 +02:00
Rafael J. Wysocki
18749317d1 thermal: core: Clean up trip bind/unbind functions
Make thermal_bind_cdev_to_trip() take a struct cooling_spec pointer
to reduce the number of its arguments, change the return type of
thermal_unbind_cdev_from_trip() to void and rearrange the code in
thermal_zone_cdev_binding() to reduce the indentation level.

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Zhang Rui <rui.zhang@intel.com>
Acked-by: Huisong Li <lihuisong@huawei.com>
Reviewed-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://patch.msgid.link/1831773.TLkxdtWsSY@rjwysocki.net
[ rjw: Changed the name of a new function argument ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2024-08-23 15:42:58 +02:00
Rafael J. Wysocki
c579286a51 thermal: core: Drop unused bind/unbind functions and callbacks
There are no more callers of thermal_zone_bind_cooling_device() and
thermal_zone_unbind_cooling_device(), so drop them along with all of
the corresponding headers, code and documentation.

Moreover, because the .bind() and .unbind() thermal zone callbacks would
only be used when the above functions, respectively, were called, drop
them as well along with all of the code related to them.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Zhang Rui <rui.zhang@intel.com>
Acked-by: Huisong Li <lihuisong@huawei.com>
Reviewed-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://patch.msgid.link/4251116.1IzOArtZ34@rjwysocki.net
2024-08-23 15:42:58 +02:00
Rafael J. Wysocki
2fb8563364 thermal: core: Unexport thermal_bind_cdev_to_trip() and thermal_unbind_cdev_from_trip()
Since thermal_bind_cdev_to_trip() and thermal_unbind_cdev_from_trip()
are only called locally in the thermal core now, they can be static,
so change their definitions accordingly and drop their headers from
the global thermal header file.

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Zhang Rui <rui.zhang@intel.com>
Acked-by: Huisong Li <lihuisong@huawei.com>
Reviewed-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://patch.msgid.link/3512161.QJadu78ljV@rjwysocki.net
2024-08-22 17:43:14 +02:00
Rafael J. Wysocki
aa35e56a52 thermal: core: Introduce .should_bind() thermal zone callback
The current design of the code binding cooling devices to trip points in
thermal zones is convoluted and hard to follow.

Namely, a driver that registers a thermal zone can provide .bind()
and .unbind() operations for it, which are required to call either
thermal_bind_cdev_to_trip() and thermal_unbind_cdev_from_trip(),
respectively, or thermal_zone_bind_cooling_device() and
thermal_zone_unbind_cooling_device(), respectively, for every relevant
trip point and the given cooling device.  Moreover, if .bind() is
provided and .unbind() is not, the cleanup necessary during the removal
of a thermal zone or a cooling device may not be carried out.

In other words, the core relies on the thermal zone owners to do the
right thing, which is error prone and far from obvious, even though all
of that is not really necessary.  Specifically, if the core could ask
the thermal zone owner, through a special thermal zone callback, whether
or not a given cooling device should be bound to a given trip point in
the given thermal zone, it might as well carry out all of the binding
and unbinding by itself.  In particular, the unbinding can be done
automatically without involving the thermal zone owner at all because
all of the thermal instances associated with a thermal zone or cooling
device going away must be deleted regardless.

Accordingly, introduce a new thermal zone operation, .should_bind(),
that can be invoked by the thermal core for a given thermal zone,
trip point and cooling device combination in order to check whether
or not the cooling device should be bound to the trip point at hand.
It takes an additional cooling_spec argument allowing the thermal
zone owner to specify the highest and lowest cooling states of the
cooling device and its weight for the given trip point binding.

Make the thermal core use this operation, if present, in the absence of
.bind() and .unbind().  Note that .should_bind() will be called under
the thermal zone lock.

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Zhang Rui <rui.zhang@intel.com>
Acked-by: Huisong Li <lihuisong@huawei.com>
Reviewed-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://patch.msgid.link/9334403.CDJkKcVGEf@rjwysocki.net
2024-08-22 17:43:14 +02:00
Rafael J. Wysocki
d48005511a thermal: core: Move thermal zone locking out of bind/unbind functions
Since thermal_bind_cdev_to_trip() and thermal_unbind_cdev_from_trip()
acquire the thermal zone lock, the locking rules for their callers get
complicated.  In particular, the thermal zone lock cannot be acquired
in any code path leading to one of these functions even though it might
be useful to do so.

To address this, remove the thermal zone locking from both these
functions, add lockdep assertions for the thermal zone lock to both
of them and make their callers acquire the thermal zone lock instead.

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Zhang Rui <rui.zhang@intel.com>
Reviewed-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://patch.msgid.link/3837835.kQq0lBPeGt@rjwysocki.net
2024-08-22 17:43:14 +02:00
Rafael J. Wysocki
eb3591cde1 thermal: core: Drop redundant thermal instance checks
Because the trip and cdev pointers are sufficient to identify a thermal
instance holding them unambiguously, drop the additional thermal zone
checks from two loops walking the list of thermal instances in a
thermal zone.

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Zhang Rui <rui.zhang@intel.com>
Reviewed-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://patch.msgid.link/10527734.nUPlyArG6x@rjwysocki.net
2024-08-22 17:43:14 +02:00
Rafael J. Wysocki
b4e6d39817 thermal: core: Rearrange checks in thermal_bind_cdev_to_trip()
It is not necessary to look up the thermal zone and the cooling device
in the respective global lists to check whether or not they are
registered.  It is sufficient to check whether or not their respective
list nodes are empty for this purpose.

Use the above observation to simplify thermal_bind_cdev_to_trip().  In
addition, eliminate an unnecessary ternary operator from it.

Moreover, add lockdep_assert_held() for thermal_list_lock to it because
that lock must be held by its callers when it is running.

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Zhang Rui <rui.zhang@intel.com>
Reviewed-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://patch.msgid.link/3324214.44csPzL39Z@rjwysocki.net
2024-08-22 17:43:14 +02:00