Re: [PATCH] 2/2 2.5.45 cleanup & add original copy_ro/from_user

From: Andrew Morton (akpm@digeo.com)
Date: Sat Nov 02 2002 - 13:13:46 EST


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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