Home
Reading
Searching
Subscribe
Sponsors
Statistics
Posting
Contact
Spam
Lists
Links
About
Hosting
Filtering
Features Download
Marketing
Archives
FAQ
Blog
 
Gmane
From: Morten Rasmussen <morten.rasmussen <at> arm.com>
Subject: [RFC][PATCH 0/7] Power-aware scheduling v2
Newsgroups: gmane.linux.kernel
Date: Friday 11th October 2013 17:19:10 UTC (over 3 years ago)
Hi,

I have revised the previous power scheduler proposal[1] trying to address
as
many of the comments as possible. The overall idea was discussed at
LPC[2,3].
The revised design has removed the power scheduler and replaced it with a
high
level power driver interface. An interface that allows the scheduler to
query
the power driver for information and provide hints to guide power
management
decisions in the power driver.

The power driver is going to be a unified platform power driver that can
replace cpufreq and cpuidle drivers. Generic power policies will be
optional
helper functions called from the power driver. Platforms may choose to
implement their own policies as part of their power driver.

This RFC series prototypes a part of the power driver interface (cpu
capacity
hints) and shows how they can be used from the scheduler. More extensive
use of
the power driver hints and queries is left for later. The focus for now is
the
power driver interface. The patch series includes a power driver/cpufreq
governor that can use existing cpufreq drivers as backend. It has been
tested
(not thoroughly) on ARM TC2. The cpufreq governor power driver
implementation
is rather horrible, but it illustrates how the power driver interface can
be
used. Native power drivers is on the todo list.

The power driver interface is still missing quite a few calls to handle:
Idle,
adding extra information to the sched_domain hierarchy to guide scheduling
decisions (packing), and possibly scaling of tracked load to compensate for
frequency changes and asymmetric systems (big.LITTLE).

This set is based on 3.11. I have done ARM TC2 testing based on
linux-linaro
2013.08[4] to get cpufreq support for TC2.


Morten

[1] https://lkml.org/lkml/2013/7/9/314

[2] http://etherpad.osuosl.org/lpc2013-power-efficient-scheduling

[3] http://www.linuxplumbersconf.org/2013/ocw//system/presentations/1263/original/Unifying_Power_Policies_LPC.pdf

[4] http://git.linaro.org/gitweb?p=kernel/linux-linaro-tracking.git


Morten Rasmussen (7):
  Initial power driver interface infrastructure
  sched: power: Power driver late callback interface
  sched: power: go_faster/slower power driver hints
  sched: power: Remove power capacity hints for kworker threads
  sched: power: Increase cpu capacity based on rq tracked load
  sched: power: cpufreq: Initial schedpower cpufreq governor/power
    driver
  sched: power: Let the power driver choose the best wake-up cpu

 arch/arm/Kconfig                     |    4 +
 drivers/cpufreq/Kconfig              |   11 ++
 drivers/cpufreq/Makefile             |    1 +
 drivers/cpufreq/cpufreq_schedpower.c |  218
++++++++++++++++++++++++++++++++++
 include/linux/sched/power.h          |   37 ++++++
 kernel/sched/Makefile                |    1 +
 kernel/sched/core.c                  |    1 +
 kernel/sched/fair.c                  |   53 ++++++++-
 kernel/sched/power.c                 |   73 ++++++++++++
 kernel/sched/sched.h                 |   32 +++++
 10 files changed, 430 insertions(+), 1 deletion(-)
 create mode 100644 drivers/cpufreq/cpufreq_schedpower.c
 create mode 100644 include/linux/sched/power.h
 create mode 100644 kernel/sched/power.c

-- 
1.7.9.5
 
CD: 3ms