From: Andi Kleen <ak@suse.de>
To: Linus Torvalds <torvalds@osdl.org>
Subject: Re: [BUG] Oops on boot (probably ACPI related)
Date: Thu, 28 Sep 2006 09:49:06 +0200
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Cc: Kyle McMartin <kyle@parisc-linux.org>, linux-kernel@vger.kernel.org,
       linux-acpi@vger.kernel.org, akpm@osdl.org, jbeulich@novell.com
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On Wednesday 27 September 2006 23:38, Linus Torvalds wrote:
> 
> On Wed, 27 Sep 2006, Andi Kleen wrote:
> > 
> > It doesn't matter much because these days this stuff is all out of lined
> > anyways and in a single function. And the dynamic branch predictor
> > in all modern CPUs will usually cache the decision (unlocked) there.
> 
> Ahh, good point. Once there's only one copy, the branch predictor will get 
> it right (and the code size won't much matter)

As a postscript I (unintentionally) bended the truth on that one actually
yesterday. Sorry for that. Semaphores are still inline, unlike spinlocks.

However if the spinlocks are out of line I see no reason to keep semaphores
inline either, so perhaps it would be better to just move them. Then my
argument above would actually work :)

For some reason the unwinder also still seems to get stuck on it :/

-Andi
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