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Message-ID: <1340800594.10063.53.camel@twins>
Subject: Re: [PATCH v4 12/13] fair.c: Use generic rbtree impl in fair
 scheduler
From: Peter Zijlstra <a.p.zijlstra@chello.nl>
To: Daniel Santos <daniel.santos@pobox.com>
Cc: Andrew Morton <akpm@linux-foundation.org>,
        Christopher Li <sparse@chrisli.org>,
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Date: Wed, 27 Jun 2012 14:36:34 +0200
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On Tue, 2012-06-26 at 16:59 -0500, Daniel Santos wrote:
> Also, to address why we're not using entity_before (or a less()
> function) directly, there's two main reasons (one that doesn't even
> affect CFS).  The first reason is that an "is equal" evaluation would
> also be required for insertions in trees with unique keys,

Right, I saw that feature in your code, are there any such trees in the
kernel? It would be good to have a kernel code conversion for each
variant your code supports.

>  as well as
> all lookups.  This doesn't doesn't affect CFS because it isn't doing
> lookups (it only cares about leftmost) and duplicate keys are allowed.
> 
Right.. there's that.

Too bad, partial order is slightly cheaper at times. A well, nothing for
it.