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Subject: Re: [linux-pm] [PATCH 0/8] Suspend block api (version 8)
From: Peter Zijlstra <peterz@infradead.org>
To: Alan Cox <alan@lxorguk.ukuu.org.uk>
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Date: Thu, 27 May 2010 17:34:39 +0200
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On Thu, 2010-05-27 at 16:33 +0100, Alan Cox wrote:
> On Thu, 27 May 2010 17:09:16 +0200
> Peter Zijlstra <peterz@infradead.org> wrote:
> 
> > On Thu, 2010-05-27 at 11:06 -0400, Alan Stern wrote:
> > > 
> > >         Opportunistic suspends are okay.
> > > 
> > >         The proposed userspace API is too Android-specific.
> > 
> > I would argue opportunistic suspends are not ok, and therefore the
> > proposed API is utterly irrelevant.
> 
> Assuming you are happy that opportunistically entering C6 and the like is
> ok via ACPI can you explain why you have a problem with opportunistic
> suspend and why it is different to a very deep sleep CPU state such as we
> have now (and which on many embedded platforms we deal with *is* sleeping
> external devices too)

Agreed, but I understood the opportunistic suspend line from Alan Stern
to mean the echo opportunistic > /sys/power/foo thing.

If you view it as an extra deep idle state I have no problem with it
(because its simply an idle state, nothing magic about those).