Re: Stack usage tasks

[Adrian Bunk <bunk@stusta.de>]

On Thu, Mar 31, 2005 at 12:43:38PM -0800, Roland Dreier wrote:
>     > The task I'm suggesting was therefore:
>     > - remove the -fno-unit-at-a-time in arch/i386/Makefile in your private
>     >   kernel sources
>     > - use gcc 3.4
>     > - reduce the stack usages in call paths > 3kB
> 
> This is a good idea.  However, I might suggest using gcc 4.0 (you'll
> have to use a snapshot now, but the release should only be a few weeks
> away).  A patch went into gcc 4.0 that makes gcc more intelligent
> about sharing stack for variables that cannot be alive at the same
> time, and therefore it may be more feasible to make unit-at-a-time
> work for the i386 kernels.

That's one option.

Jörn, can you send a list of call paths with a stack usage > 3kB when 
compiling with gcc 3.4 and unit-at-a-time (or tell me how to generate 
these lists)?

If fixing a handful of places was sufficient, it was IMHO worth it for 
enabling unit-at-a-time with gcc 3.4 .

>  - R.

cu
Adrian

-- 

       "Is there not promise of rain?" Ling Tan asked suddenly out
        of the darkness. There had been need of rain for many days.
       "Only a promise," Lao Er said.
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