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From: Andi Kleen <ak@suse.de>
To: bidulock@openss7.org
Subject: Re: [PATCH] use unlikely() for current_kernel_time() loop
Date: Thu, 8 Jun 2006 11:14:09 +0200
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> performance increased 2% per hyperthread; 

That would surprise me. Most likely you made some measurement error.

I guess it can be a difference if it's used in very hot loops, but then
i would expect a fallthrough path to win. Kernel code very rarely
has hot loops like this.

-Andi