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SubjectRe: likely/unlikely
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.


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