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From: "Rafael J. Wysocki" <rjw@sisk.pl>
To: Oliver Neukum <oliver@neukum.org>
Subject: Re: [RFD] Automatic suspend
Date: Fri, 20 Feb 2009 11:46:55 +0100
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Cc: Alan Stern <stern@rowland.harvard.edu>,
       Arve =?iso-8859-1?q?Hj=F8nnev=E5g?= <arve@android.com>,
       "Woodruff, Richard" <r-woodruff2@ti.com>,
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       Nigel Cunningham <nigel@nigel.suspend2.net>,
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       mark gross <mgross@linux.intel.com>, Uli Luckas <u.luckas@road.de>,
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       Brian Swetland <swetland@google.com>, Len Brown <lenb@kernel.org>
References: <Pine.LNX.4.44L0.0902191659020.7953-100000@iolanthe.rowland.org> <200902192321.47891.rjw@sisk.pl> <200902192358.13068.oliver@neukum.org>
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On Thursday 19 February 2009, Oliver Neukum wrote:
> Am Donnerstag 19 Februar 2009 23:21:46 schrieb Rafael J. Wysocki:
> > > That's the whole point behind userspace wakelocks!  They provide a
> > > mechanism for userspace to tell the kernel when (as far as userspace 
> is
> > > concerned) it is or is not okay to auto-sleep.
> >
> > Still, one can go further and observe that the user space can in fact start
> > automatic suspend by itself whenever it knows it's appropriate ...
> 
> User space initiating this is a race condition.

Do you mean a race with the other user space processes or with the kernel?

Rafael