cpuidle: support for multi-cluster in the core

Registered by David Zinman

This blueprint has been moved to JIRA: https://cards.linaro.org/browse/PMWG-259

This is a tracking blueprint only since the actual work is done by Lorenzo who is not an assignee with perhaps some help from Daniel.

Blueprint information

Status:
Complete
Approver:
Amit Kucheria
Priority:
Medium
Drafter:
Amit Kucheria
Direction:
Approved
Assignee:
Daniel Lezcano
Definition:
Superseded
Series goal:
Accepted for trunk
Implementation:
Slow progress
Milestone target:
milestone icon 2013.03
Started by
Amit Kucheria
Completed by
Serge Broslavsky

Related branches

Sprints

Whiteboard

[dzin, 2012-11-24] Moved to 12.12 for visibility. There are no details to this blueprint as of yet.
[amitk, 2012-11-28] Since Lorenzo isn't an assignee, this is just an informative blueprint for tracking purposes. The work will be done inside ARM according to their schedules. Also, this code depends on Nico's power API on IKS. Waiting for it to be upstreamed.

[daniel-lezcano, 2012-11-29] There are some areas of investigations on how to improve cluster shutdown. First we need a tool to check the improvements made for the cluster shutdown, let's call it "idlestat". After this we can prototype some modifications in the kernel and measure the improvements.

[daniel-lezcano, 2012-12-07] It is important to understand how behaves the system before trying to improve anything else. The first step is to dig into the /proc/interrupts file and identify why and when the interrupts occur, most of them are trivial but other are not.

[daniel-lezcano, 2012-12-07] The wiki page has been created to document the wakeup sources. https://wiki.linaro.org/WorkingGroups/PowerManagement/Doc/WakeUpSources

[daniel-lezcano, 2012-12-07] The timer interrupt is a source of wakeup. The /proc/timer_list contains a lot of useful information about how is used the timer, which application setup a timer and more.

[dzin, 2013-01-25] Bump to 13.02

[daniel-lezcano, 2013-04-03] Created and moved the idlestat related info and WI to the blueprint:
https://blueprints.launchpad.net/linaro-power-kernel/+spec/cpuidle-userspace-tool

Meta:
Headline: TBD
Acceptance: TBD

(?)

Work Items

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