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From: Andi Kleen <ak@suse.de>
To: Christoph Lameter <clameter@sgi.com>
Subject: Re: broken local_t on i386
Date: Mon, 12 Jun 2006 19:55:47 +0200
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Cc: Ingo Molnar <mingo@elte.hu>,
       Michal Piotrowski <michal.k.k.piotrowski@gmail.com>,
       Andrew Morton <akpm@osdl.org>, linux-kernel@vger.kernel.org
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On Monday 12 June 2006 20:42, Christoph Lameter wrote:
> On Mon, 12 Jun 2006, Andi Kleen wrote:
> > Saving two instructions? And PDA is usually in L1. I doubt you could
> > benchmark a difference.
>
> The two instructions occur over and over again for each PDA reference. And
> then there are now two more instruction for disabling preempt and
> reenabling preempt.

Only for those who set CONFIG_OVERHEAD

> A simple dec/inc <absolute location> would be nicely suitable for
> inlining per processor counters.

Possible, but is it worth reinventing the linker?

-Andi