From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Ai Li" <aili@codeaurora.org>
Subject: Re: PM-QOS hot path discussion.
Date: Wed, 27 Jan 2010 12:08:22 -0700
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To: 'Mike Chan' <mike@android.com>
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> There are a few lower power states on msm that we don't
> differentiate
> between when taking an idle lock.
> 
> We don't use idle locks on omap. The resource framework in the
> omap
> tree is sufficient with the latency requirement calls in
> resource34xx.c/h
> 
> I might be wrong here but it sounds like you're trying to solve
> a
> similar problem but working it into the pm-qos framework? Or am
> I
> confused on what the subject of this thread is?

pm_qos framework handles latency requirements already and can be used
on all platforms.  Our code at codeaurora.org for MSM chips uses
pm_qos for latency.  This thread discusses improving efficient
execution of pm_qos in hot-path, i.e. when pm_qos is called very
frequently.  The improvement would apply to all pm_qos parameters,
not just latency.  The latency implementations in pm_qos and in
android's WAKE_LOCK_IDLE are references as to what have been done
already.

There is a related discussion in the thread "[linux-pm] platform
specific pm_qos parameters".  That thread focuses on how to add
platform-specifc parameters to pm_qos, i.e. creating a mechanism so
that each platform (i.e. x86, OMAP, MSM) can append its own set of
pm_qos parameters and associated behavior.

~Ai