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To: Denis Vlasenko <vda@ilport.com.ua>
Cc: linux-kernel@vger.kernel.org
Subject: Re: [RFC] exit_thread() speedups in x86 process.c
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From: Andi Kleen <ak@suse.de>
Date: 03 Jul 2005 18:05:03 +0200
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Denis Vlasenko <vda@ilport.com.ua> writes:
> 
> 80/20 rule says that 80% of code runs 20% of time,
> thus we need only __fast. Everything else will be by default __slow.
> (IOW: normal .text section is __slow, no need to add another one).

__slow could include noinline.  With unit-at-a-time gcc tends 
otherwise to inline too aggressively. With __fast that would not be
possible.


-Andi

P.S.: gcc 4.x already supports .cold even on the basic block level.
However I believe it's only active with profile feedback, which is not
practical for kernel builds.