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Date: Wed, 26 May 2010 13:49:29 +0100
From: Matthew Garrett <mjg59@srcf.ucam.org>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Arve =?iso-8859-1?B?SGr4bm5lduVn?= <arve@android.com>,
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Subject: Re: [PATCH 1/8] PM: Opportunistic suspend support.
Message-ID: <20100526124929.GA32580@srcf.ucam.org>
References: <Pine.LNX.4.44L0.1005251647530.1634-100000@iolanthe.rowland.org> <201005252344.37639.rjw@sisk.pl> <AANLkTimL5rU5lALezEZVCwdcZL85tVahhsTibdpq9s-Y@mail.gmail.com> <1274863342.5882.4850.camel@twins> <1274863987.5882.4892.camel@twins>
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While this approach could be made to work, it's ugly in other ways. 
After wakeup, userspace has to pause for a while before it can trigger 
another sleep in order to give all the apps an opportunity to check for 
wakeup events and block suspend if they wish to. That's additional 
runtime that doesn't exist in the kernel-mediated case.

-- 
Matthew Garrett | mjg59@srcf.ucam.org