Date: Tue, 10 Aug 2010 15:44:05 +0100
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: paulmck@linux.vnet.ibm.com, "Ted Ts'o" <tytso@mit.edu>,
        Felipe Contreras <felipe.contreras@gmail.com>, david@lang.hm,
        Brian Swetland <swetland@google.com>,
        linux-pm@lists.linux-foundation.org, linux-kernel@vger.kernel.org,
        arve@android.com, pavel@ucw.cz, florian@mickler.org, rjw@sisk.pl,
        stern@rowland.harvard.edu, peterz@infradead.org, tglx@linutronix.de,
        menage@google.com, david-b@pacbell.net, James.Bottomley@suse.de,
        arjan@infradead.org, swmike@swm.pp.se, galibert@pobox.com,
        dipankar@in.ibm.com
Subject: Re: Attempted summary of suspend-blockers LKML thread, take three
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Which reminds me. I forgot a very important way that user space signals
the kernel as to its intents.

The kernel can see whether code is sleeping by choice or sleeping because
someone blocked it (eg a page fault). The kernel also knows a lot about
the event being waited for (much more so in -rt than base).

We don't capture all of that info but it seems it would advance progress
in the right direction to do so better.

Alan

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