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Date: Sat, 02 Nov 2002 10:13:46 -0800
From: Andrew Morton <akpm@digeo.com>
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To: Akira Tsukamoto <at541@columbia.edu>
CC: linux-kernel@vger.kernel.org, Hirokazu Takahashi <taka@valinux.co.jp>
Subject: Re: [PATCH] 2/2 2.5.45 cleanup & add original copy_ro/from_user
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Akira Tsukamoto wrote:
> 
> On Sat, 02 Nov 2002 02:32:32 -0800
> Andrew Morton <akpm@digeo.com> mentioned:
> 
> > Akira Tsukamoto wrote:
> > >
> > But you've inlined them again.  Your patches increase my kernel
> > size by 17 kbytes, which is larger than my entire Layer 1 instruction
> > cache!
> 
> It is because I was working on this patch based on 2.5.44 :)
> 
> As Andi mentioned, how about selecting if OCNFIG_SAMLL is defined?

Well you could make it dependent on CONFIG_SLOW_KERNEL ;)

It's an act of faith - we have no benchmarks on this.  But it
goes like this:

- subroutine calls are fast
- cache misses are slow
- kernel has no right to be evicting user code from the CPU cache
- smaller is faster
- inlining to the point of increasing code size is probably wrong
-
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