linux-kernel - [PATCH v4 0/5] Rework system pressure interface to the scheduler

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-Id: <20240109164655.626085-1-vincent.guittot@linaro.org>
Date: Tue,  9 Jan 2024 17:46:50 +0100
From: Vincent Guittot <vincent.guittot@...aro.org>
To: linux@...linux.org.uk,
	catalin.marinas@....com,
	will@...nel.org,
	sudeep.holla@....com,
	rafael@...nel.org,
	viresh.kumar@...aro.org,
	agross@...nel.org,
	andersson@...nel.org,
	konrad.dybcio@...aro.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,
	lukasz.luba@....com,
	rui.zhang@...el.com,
	mhiramat@...nel.org,
	daniel.lezcano@...aro.org,
	amit.kachhap@...il.com,
	corbet@....net,
	gregkh@...uxfoundation.org,
	linux-arm-kernel@...ts.infradead.org,
	linux-kernel@...r.kernel.org,
	linux-pm@...r.kernel.org,
	linux-arm-msm@...r.kernel.org,
	linux-trace-kernel@...r.kernel.org,
	linux-doc@...r.kernel.org
Cc: qyousef@...alina.io,
	Vincent Guittot <vincent.guittot@...aro.org>
Subject: [PATCH v4 0/5] Rework system pressure interface to the scheduler

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/

Change since v3:
- Fix uninitialized variables in cpufreq_update_pressure()

Change since v2:
- Rework cpufreq_update_pressure()

Change since v1:
- Use struct cpufreq_policy as parameter of cpufreq_update_pressure()
- Fix typos and comments
- Make sched_thermal_decay_shift boot param as deprecated

Vincent Guittot (5):
  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
  sched/pelt: Remove shift of thermal clock

 .../admin-guide/kernel-parameters.txt         |  1 +
 arch/arm/include/asm/topology.h               |  6 +-
 arch/arm64/include/asm/topology.h             |  6 +-
 drivers/base/arch_topology.c                  | 26 ++++----
 drivers/cpufreq/cpufreq.c                     | 36 +++++++++++
 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                           | 63 +++++++++----------
 kernel/sched/pelt.c                           | 18 +++---
 kernel/sched/pelt.h                           | 16 ++---
 kernel/sched/sched.h                          | 22 +------
 18 files changed, 144 insertions(+), 119 deletions(-)
 rename include/trace/events/{thermal_pressure.h => hw_pressure.h} (55%)

-- 
2.34.1