linux-stable.git/kernel/power/energy_model.c, branch linux-5.11.y Linux kernel stable tree PM: EM: postpone creating the debugfs dir till fs_initcall 2021-03-30T12:30:26+00:00 Lukasz Luba lukasz.luba@arm.com 2021-03-23T14:56:08+00:00 e5932c5c55fa34fda3c1809118032870b865efc6 [ Upstream commit fb9d62b27ab1e07d625591549c314b7d406d21df ] The debugfs directory '/sys/kernel/debug/energy_model' is needed before the Energy Model registration can happen. With the recent change in debugfs subsystem it's not allowed to create this directory at early stage (core_initcall). Thus creating this directory would fail. Postpone the creation of the EM debug dir to later stage: fs_initcall. It should be safe since all clients: CPUFreq drivers, Devfreq drivers will be initialized in later stages. The custom debug log below prints the time of creation the EM debug dir at fs_initcall and successful registration of EMs at later stages. [ 1.505717] energy_model: creating rootdir [ 3.698307] cpu cpu0: EM: created perf domain [ 3.709022] cpu cpu1: EM: created perf domain Fixes: 56348560d495 ("debugfs: do not attempt to create a new file before the filesystem is initalized") Reported-by: Ionela Voinescu <ionela.voinescu@arm.com> Signed-off-by: Lukasz Luba <lukasz.luba@arm.com> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit fb9d62b27ab1e07d625591549c314b7d406d21df ]

The debugfs directory '/sys/kernel/debug/energy_model' is needed before
the Energy Model registration can happen. With the recent change in
debugfs subsystem it's not allowed to create this directory at early
stage (core_initcall). Thus creating this directory would fail.

Postpone the creation of the EM debug dir to later stage: fs_initcall.

It should be safe since all clients: CPUFreq drivers, Devfreq drivers
will be initialized in later stages.

The custom debug log below prints the time of creation the EM debug dir
at fs_initcall and successful registration of EMs at later stages.

[    1.505717] energy_model: creating rootdir
[    3.698307] cpu cpu0: EM: created perf domain
[    3.709022] cpu cpu1: EM: created perf domain

Fixes: 56348560d495 ("debugfs: do not attempt to create a new file before the filesystem is initalized")
Reported-by: Ionela Voinescu <ionela.voinescu@arm.com>
Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
PM: EM: update the comments related to power scale 2020-11-10T19:29:28+00:00 Lukasz Luba lukasz.luba@arm.com 2020-11-03T09:05:59+00:00 f2c90b12e700fff6a0b5a1c32f446f05f9d0890c The Energy Model supports power values expressed in milli-Watts or in an 'abstract scale'. Update the related comments is the code to reflect that state. Reviewed-by: Quentin Perret <qperret@google.com> Signed-off-by: Lukasz Luba <lukasz.luba@arm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> 
The Energy Model supports power values expressed in milli-Watts or in an
'abstract scale'. Update the related comments is the code to reflect that
state.

Reviewed-by: Quentin Perret <qperret@google.com>
Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
PM: EM: Add a flag indicating units of power values in Energy Model 2020-11-10T19:22:00+00:00 Lukasz Luba lukasz.luba@arm.com 2020-11-05T12:50:01+00:00 c250d50fe2ce627ca9805d9c8ac11cbbf922a4a6 There are different platforms and devices which might use different scale for the power values. Kernel sub-systems might need to check if all Energy Model (EM) devices are using the same scale. Address that issue and store the information inside EM for each device. Thanks to that they can be easily compared and proper action triggered. Suggested-by: Daniel Lezcano <daniel.lezcano@linaro.org> Reviewed-by: Quentin Perret <qperret@google.com> Signed-off-by: Lukasz Luba <lukasz.luba@arm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> 
There are different platforms and devices which might use different scale
for the power values. Kernel sub-systems might need to check if all
Energy Model (EM) devices are using the same scale. Address that issue and
store the information inside EM for each device. Thanks to that they can
be easily compared and proper action triggered.

Suggested-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: Quentin Perret <qperret@google.com>
Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
PM / EM: remove em_register_perf_domain 2020-06-24T15:16:42+00:00 Lukasz Luba lukasz.luba@arm.com 2020-05-27T09:58:51+00:00 07891f15d91317b2220a0b610a2d7e324a88105d Remove old function em_register_perf_domain which is no longer needed. There is em_dev_register_perf_domain that covers old use cases and new as well. Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Quentin Perret <qperret@google.com> Signed-off-by: Lukasz Luba <lukasz.luba@arm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> 
Remove old function em_register_perf_domain which is no longer needed.
There is em_dev_register_perf_domain that covers old use cases and new as
well.

Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Quentin Perret <qperret@google.com>
Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
PM / EM: add support for other devices than CPUs in Energy Model 2020-06-24T15:16:27+00:00 Lukasz Luba lukasz.luba@arm.com 2020-06-10T10:12:23+00:00 1bc138c622959979eb547be2d3bbc6442a5c80b0 Add support for other devices than CPUs. The registration function does not require a valid cpumask pointer and is ready to handle new devices. Some of the internal structures has been reorganized in order to keep consistent view (like removing per_cpu pd pointers). Signed-off-by: Lukasz Luba <lukasz.luba@arm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> 
Add support for other devices than CPUs. The registration function
does not require a valid cpumask pointer and is ready to handle new
devices. Some of the internal structures has been reorganized in order to
keep consistent view (like removing per_cpu pd pointers).

Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
PM / EM: update callback structure and add device pointer 2020-06-24T15:14:07+00:00 Lukasz Luba lukasz.luba@arm.com 2020-05-27T09:58:49+00:00 d0351cc3b0f57214d157e4d589564730af2aedae The Energy Model framework is going to support devices other that CPUs. In order to make this happen change the callback function and add pointer to a device as an argument. Update the related users to use new function and new callback from the Energy Model. Acked-by: Quentin Perret <qperret@google.com> Signed-off-by: Lukasz Luba <lukasz.luba@arm.com> Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> 
The Energy Model framework is going to support devices other that CPUs. In
order to make this happen change the callback function and add pointer to
a device as an argument.

Update the related users to use new function and new callback from the
Energy Model.

Acked-by: Quentin Perret <qperret@google.com>
Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
PM / EM: introduce em_dev_register_perf_domain function 2020-06-24T15:14:07+00:00 Lukasz Luba lukasz.luba@arm.com 2020-05-27T09:58:48+00:00 7d9895c7fbfc9c70afce7029b7de0f3f974adb88 Add now function in the Energy Model framework which is going to support new devices. This function will help in transition and make it smoother. For now it still checks if the cpumask is a valid pointer, which will be removed later when the new structures and infrastructure will be ready. Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Quentin Perret <qperret@google.com> Signed-off-by: Lukasz Luba <lukasz.luba@arm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> 
Add now function in the Energy Model framework which is going to support
new devices. This function will help in transition and make it smoother.
For now it still checks if the cpumask is a valid pointer, which will be
removed later when the new structures and infrastructure will be ready.

Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Quentin Perret <qperret@google.com>
Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
PM / EM: change naming convention from 'capacity' to 'performance' 2020-06-24T15:14:07+00:00 Lukasz Luba lukasz.luba@arm.com 2020-05-27T09:58:47+00:00 521b512b157a1315ff2bf11c11ab184c79515aea The Energy Model uses concept of performance domain and capacity states in order to calculate power used by CPUs. Change naming convention from capacity to performance state would enable wider usage in future, e.g. upcoming support for other devices other than CPUs. Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Quentin Perret <qperret@google.com> Signed-off-by: Lukasz Luba <lukasz.luba@arm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> 
The Energy Model uses concept of performance domain and capacity states in
order to calculate power used by CPUs. Change naming convention from
capacity to performance state would enable wider usage in future, e.g.
upcoming support for other devices other than CPUs.

Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Quentin Perret <qperret@google.com>
Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
sched/topology: Remove unused 'sd' parameter from arch_scale_cpu_capacity() 2019-06-24T17:23:39+00:00 Vincent Guittot vincent.guittot@linaro.org 2019-06-17T15:00:17+00:00 8ec59c0f5f4966f89f4e3e3cab81710c7fa959d0 The 'struct sched_domain *sd' parameter to arch_scale_cpu_capacity() is unused since commit: 765d0af19f5f ("sched/topology: Remove the ::smt_gain field from 'struct sched_domain'") Remove it. Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Reviewed-by: Valentin Schneider <valentin.schneider@arm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: gregkh@linuxfoundation.org Cc: linux@armlinux.org.uk Cc: quentin.perret@arm.com Cc: rafael@kernel.org Link: https://lkml.kernel.org/r/1560783617-5827-1-git-send-email-vincent.guittot@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org> 
The 'struct sched_domain *sd' parameter to arch_scale_cpu_capacity() is
unused since commit:

  765d0af19f5f ("sched/topology: Remove the ::smt_gain field from 'struct sched_domain'")

Remove it.

Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Valentin Schneider <valentin.schneider@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: gregkh@linuxfoundation.org
Cc: linux@armlinux.org.uk
Cc: quentin.perret@arm.com
Cc: rafael@kernel.org
Link: https://lkml.kernel.org/r/1560783617-5827-1-git-send-email-vincent.guittot@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
PM / EM: Expose the Energy Model in debugfs 2019-01-23T22:07:57+00:00 Quentin Perret quentin.perret@arm.com 2019-01-22T16:42:47+00:00 9cac42d0645ceb2ca8b815cee04810ec9b0d13b3 The recently introduced Energy Model (EM) framework manages power cost tables of CPUs. These tables are currently only visible from kernel space. However, in order to debug the behaviour of subsystems that use the EM (EAS for example), it is often required to know what the power costs are from userspace. For this reason, introduce under /sys/kernel/debug/energy_model a set of directories representing the performance domains of the system. Each performance domain contains a set of sub-directories representing the different capacity states (cs) and their attributes, as well as a file exposing the related CPUs. The resulting hierarchy is as follows on Arm juno r0 for example: /sys/kernel/debug/energy_model ├── pd0 │   ├── cpus │   ├── cs:450000 │   │   ├── cost │   │   ├── frequency │   │   └── power │   ├── cs:575000 │   │   ├── cost │   │   ├── frequency │   │   └── power │   ├── cs:700000 │   │   ├── cost │   │   ├── frequency │   │   └── power │   ├── cs:775000 │   │   ├── cost │   │   ├── frequency │   │   └── power │   └── cs:850000 │   ├── cost │   ├── frequency │   └── power └── pd1 ├── cpus ├── cs:1100000 │   ├── cost │   ├── frequency │   └── power ├── cs:450000 │   ├── cost │   ├── frequency │   └── power ├── cs:625000 │   ├── cost │   ├── frequency │   └── power ├── cs:800000 │   ├── cost │   ├── frequency │   └── power └── cs:950000 ├── cost ├── frequency └── power Signed-off-by: Quentin Perret <quentin.perret@arm.com> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> 
The recently introduced Energy Model (EM) framework manages power cost
tables of CPUs. These tables are currently only visible from kernel
space. However, in order to debug the behaviour of subsystems that use
the EM (EAS for example), it is often required to know what the power
costs are from userspace.

For this reason, introduce under /sys/kernel/debug/energy_model a set of
directories representing the performance domains of the system. Each
performance domain contains a set of sub-directories representing the
different capacity states (cs) and their attributes, as well as a file
exposing the related CPUs.

The resulting hierarchy is as follows on Arm juno r0 for example:

    /sys/kernel/debug/energy_model
    ├── pd0
    │   ├── cpus
    │   ├── cs:450000
    │   │   ├── cost
    │   │   ├── frequency
    │   │   └── power
    │   ├── cs:575000
    │   │   ├── cost
    │   │   ├── frequency
    │   │   └── power
    │   ├── cs:700000
    │   │   ├── cost
    │   │   ├── frequency
    │   │   └── power
    │   ├── cs:775000
    │   │   ├── cost
    │   │   ├── frequency
    │   │   └── power
    │   └── cs:850000
    │       ├── cost
    │       ├── frequency
    │       └── power
    └── pd1
        ├── cpus
        ├── cs:1100000
        │   ├── cost
        │   ├── frequency
        │   └── power
        ├── cs:450000
        │   ├── cost
        │   ├── frequency
        │   └── power
        ├── cs:625000
        │   ├── cost
        │   ├── frequency
        │   └── power
        ├── cs:800000
        │   ├── cost
        │   ├── frequency
        │   └── power
        └── cs:950000
            ├── cost
            ├── frequency
            └── power

Signed-off-by: Quentin Perret <quentin.perret@arm.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>