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Subject: Re: [PATCH 06/13] writeback: bdi write bandwidth estimation
From: Peter Zijlstra <a.p.zijlstra@chello.nl>
To: Wu Fengguang <fengguang.wu@intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>, Jan Kara <jack@suse.cz>,
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Date: Wed, 24 Nov 2010 14:42:09 +0100
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On Wed, 2010-11-24 at 21:20 +0800, Wu Fengguang wrote:
> >         (jiffies - bdi->write_bandwidth_update_time < elapsed)
> 
> this will be true if someone else has _done_ overlapped estimation,
> otherwise it will equal:
> 
>         jiffies - bdi->write_bandwidth_update_time == elapsed
> 
> Sorry the comment needs updating. 

Right, but its racy as hell..