From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andi Kleen <andi@firstfloor.org>
Subject: Re: [patch 00/41] cpu alloc / cpu ops v3: Optimize per cpu access
Date: Mon, 09 Jun 2008 21:11:54 +0200
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In-Reply-To: <Pine.LNX.4.64.0806091136410.30727@schroedinger.engr.sgi.com> (Christoph Lameter's message of "Mon, 9 Jun 2008 11:44:23 -0700 (PDT)")
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To: Christoph Lameter <clameter@sgi.com>
Cc: Eric Dumazet <dada1@cosmosbay.com>, Mike Travis <travis@sgi.com>, Andrew Morton <akpm@linux-foundation.org>, linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org, David Miller <davem@davemloft.net>, Peter Zijlstra <peterz@infradead.org>, Rusty Russell <rusty@rustcorp.com.au>

Christoph Lameter <clameter@sgi.com> writes:

> The problem is that offsets relative to %gs or %fs are limited by the 
> small memory model that is chosen.

Actually they are not. If you really want you can do 
movabs $64bit,%reg ; op ...,%gs:(%reg) 
It's just not very efficient compared to small (or rather kernel) model
and also older binutils didn't support large model.

-Andi