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Date: Wed, 16 Jan 2002 08:38:56 +0100 (CET)
From: Adrian Bunk <bunk@fs.tum.de>
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To: Craig Christophel <merlin@transgeek.com>
cc: linux-kernel@vger.kernel.org
Subject: Re: likely/unlikely
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On Wed, 16 Jan 2002, Craig Christophel wrote:

> > likely/unlikely set the branch prediction values to 99% or 1%
>
>
> 	So all of the BUG() routines in the kernel would benifit greatly from this.

In the 2.5 kernels this is done when you use the BUG_ON macro that is
defined as follows:

#define BUG_ON(condition) do { if (unlikely((condition)!=0)) BUG(); } while(0)


BTW: Note that likely/unlikely doesn't has any effect for most of us
     because __builtin_expect is only available in gcc >= 2.96.


> Craig.

cu
Adrian


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