Message-Id: <20231009103621.374412-1-vincent.guittot@linaro.org>
Date:   Mon,  9 Oct 2023 12:36:15 +0200
From:   Vincent Guittot <vincent.guittot@...aro.org>
To:     linux@...linux.org.uk, catalin.marinas@....com, will@...nel.org,
        paul.walmsley@...ive.com, palmer@...belt.com,
        aou@...s.berkeley.edu, sudeep.holla@....com,
        gregkh@...uxfoundation.org, rafael@...nel.org, mingo@...hat.com,
        peterz@...radead.org, juri.lelli@...hat.com,
        dietmar.eggemann@....com, rostedt@...dmis.org, bsegall@...gle.com,
        mgorman@...e.de, bristot@...hat.com, vschneid@...hat.com,
        viresh.kumar@...aro.org, lukasz.luba@....com,
        ionela.voinescu@....com, pierre.gondois@....com,
        linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org,
        linux-riscv@...ts.infradead.org, linux-pm@...r.kernel.org
Cc:     conor.dooley@...rochip.com, suagrfillet@...il.com,
        ajones@...tanamicro.com, lftan@...nel.org,
        Vincent Guittot <vincent.guittot@...aro.org>
Subject: [PATCH v2 0/6] consolidate and cleanup CPU capacity

This is the 1st part of consolidating how the max compute capacity is
used in the scheduler and how we calculate the frequency for a level of
utilization.

Fix some unconsistancy when computing frequency for an utilization. There
can be a mismatch between energy model and schedutil.

Next step will be to make a difference between the original
max compute capacity of a CPU and what is currently available when
there is a capping applying forever (i.e. seconds or more).


Changes since v1:
- Fix typos
- Added changes in cpufreq to use arch_scale_freq_ref() when calling
  arch_set_freq_scale (patch 3).
- arch_scale_freq_ref() is always defined and returns 0 (as proposed
  by Ionela) when not defined by the arch. This simplifies the code with
  the addition of patch 3.
- Simplify Energy Model which always uses arch_scale_freq_ref(). The
  latter returns 0 when not defined by arch instead of last item of the 
  perf domain. This is not a problem because the function is only defined
  for compilation purpose in this case and we don't care about the
  returned value. (patch 5)
- Added changes in cppc cpufreq to set capacity_ref_freq (patch 6)
- Added reviewed tag for patch 1 which got a minor change but not for
  others as I did some changes which could make previous reviewed tag
  no more relevant.

Vincent Guittot (6):
  sched: consolidate and cleanup access to CPU's max compute capacity
  topology: add a new arch_scale_freq_reference
  cpufreq: use the fixed and coherent frequency for scaling capacity
  cpufreq/schedutil: use a fixed reference frequency
  energy_model: use a fixed reference frequency
  cpufreq/cppc: set the frequency used for capacity computation

 Documentation/scheduler/sched-capacity.rst | 13 +++++-----
 arch/arm/include/asm/topology.h            |  1 +
 arch/arm64/include/asm/topology.h          |  1 +
 arch/riscv/include/asm/topology.h          |  1 +
 drivers/base/arch_topology.c               | 29 +++++++++++-----------
 drivers/cpufreq/cppc_cpufreq.c             | 18 ++++++++++++++
 drivers/cpufreq/cpufreq.c                  |  4 +--
 include/linux/arch_topology.h              |  7 ++++++
 include/linux/cpufreq.h                    |  9 +++++++
 include/linux/energy_model.h               | 14 ++++++++---
 kernel/sched/core.c                        |  2 +-
 kernel/sched/cpudeadline.c                 |  2 +-
 kernel/sched/cpufreq_schedutil.c           | 26 +++++++++++++++++--
 kernel/sched/deadline.c                    |  4 +--
 kernel/sched/fair.c                        | 18 ++++++--------
 kernel/sched/rt.c                          |  2 +-
 kernel/sched/sched.h                       |  6 -----
 kernel/sched/topology.c                    |  7 ++++--
 18 files changed, 113 insertions(+), 51 deletions(-)

-- 
2.34.1

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