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Subject: Re: [PATCH 1/8] PM: Opportunistic suspend support.
From: Peter Zijlstra <peterz@infradead.org>
To: James Bottomley <James.Bottomley@suse.de>
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Date: Wed, 26 May 2010 18:28:28 +0200
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On Wed, 2010-05-26 at 11:18 -0500, James Bottomley wrote:
> > Or make the suspend manager a C proglet and provide a JNI interface,
> > or whatever.
> 
> It's a fairly large piece of code to try to rewrite in C, so I don't
> think that's feasible on a reasonable timescale.  Android does have the
> concept of special sockets that can be used to communicate from less to
> more privileged processes (it has a very segmented runtime model), so
> these might be usable ... they have a drawback that they're essentially
> named pipes, so no multiplexing, but one per suspend influencing C
> process shouldn't be a huge burden. 

It wouldn't need to convert the whole Frameworks layer into C, just
enough to manage the suspend state.

Anyway, I think there's been enough arguments against even the concept
of opportunistic/auto-suspend, and I for one will object with a NAK if
Rafael send this to Linus.

The whole idea of segregating userspace like that, and not letting
runnable thing run is very ill considered indeed.