[PATCH 0/5] Rework system pressure interface to the scheduler

Vincent Guittot vincent.guittot at linaro.org
Tue Dec 12 06:27:26 PST 2023


Following the consolidation and cleanup of CPU capacity in [1], this serie
reworks how the scheduler gets the pressures on CPUs. We need to take into
account all pressures applied by cpufreq on the compute capacity of a CPU
for dozens of ms or more and not only cpufreq cooling device or HW
mitigiations. we split the pressure applied on CPU's capacity in 2 parts:
- one from cpufreq and freq_qos
- one from HW high freq mitigiation.

The next step will be to add a dedicated interface for long standing
capping of the CPU capacity (i.e. for seconds or more) like the
scaling_max_freq of cpufreq sysfs. The latter is already taken into
account by this serie but as a temporary pressure which is not always the
best choice when we know that it will happen for seconds or more.

[1] https://lore.kernel.org/lkml/20231211104855.558096-1-vincent.guittot@linaro.org/

Vincent Guittot (4):
  cpufreq: Add a cpufreq pressure feedback for the scheduler
  sched: Take cpufreq feedback into account
  thermal/cpufreq: Remove arch_update_thermal_pressure()
  sched: Rename arch_update_thermal_pressure into
    arch_update_hw_pressure

 arch/arm/include/asm/topology.h               |  6 +--
 arch/arm64/include/asm/topology.h             |  6 +--
 drivers/base/arch_topology.c                  | 26 ++++-----
 drivers/cpufreq/cpufreq.c                     | 48 +++++++++++++++++
 drivers/cpufreq/qcom-cpufreq-hw.c             |  4 +-
 drivers/thermal/cpufreq_cooling.c             |  3 --
 include/linux/arch_topology.h                 |  8 +--
 include/linux/cpufreq.h                       | 10 ++++
 include/linux/sched/topology.h                |  8 +--
 .../{thermal_pressure.h => hw_pressure.h}     | 14 ++---
 include/trace/events/sched.h                  |  2 +-
 init/Kconfig                                  | 12 ++---
 kernel/sched/core.c                           |  8 +--
 kernel/sched/fair.c                           | 53 ++++++++++---------
 kernel/sched/pelt.c                           | 18 +++----
 kernel/sched/pelt.h                           | 16 +++---
 kernel/sched/sched.h                          |  4 +-
 17 files changed, 152 insertions(+), 94 deletions(-)
 rename include/trace/events/{thermal_pressure.h => hw_pressure.h} (55%)

-- 
2.34.1
 



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