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Date: Fri, 12 May 2006 13:12:56 +0200
From: Ingo Molnar <mingo@elte.hu>
To: =?iso-8859-1?Q?S=E9bastien_Dugu=E9?= <sebastien.dugue@bull.net>
Cc: Andrew Morton <akpm@osdl.org>, linux-kernel@vger.kernel.org,
       tglx@linutronix.de
Subject: Re: [RFC][PATCH RT 1/2] futex_requeue-optimize
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* Sébastien Dugué <sebastien.dugue@bull.net> wrote:

> On Fri, 2006-05-12 at 10:10 +0200, Sébastien Dugué wrote:
> > On Fri, 2006-05-12 at 08:32 +0200, Ingo Molnar wrote:
> > > * Andrew Morton <akpm@osdl.org> wrote:
> > > 
> > > > Should the futex code be using hlist_heads for that hashtable?
> > > 
> > > yeah. That would save 1K of .data on 32-bit platforms, 2K on 64-bit 
> > > platforms.
> > 
> >   I'll try to look into this.
> > 
> 
>   Well, moving the hash bucket list to an hlist may save a few bytes 
> on .data, but all the insertions are done at the tail on this list 
> which would not be easily done using hlists.
> 
>   Any thoughts?

just queue to the head. This is a hash-list, ordering has only 
performance effects.

	Ingo