Re: cpufreq 'choice' Kconfig oddness in 2.6.22-rc6-mm1..

From: Mattia Dongili
Date: Sat Jul 07 2007 - 02:50:23 EST


On Sat, Jul 07, 2007 at 12:35:10AM -0400, Valdis.Kletnieks@xxxxxx wrote:
> So I was looking at drivers/cpufreq/Kconfig, and wondering...
>
> Is there a specific reason why we have a 'choice' clause that allows selecting
> 'performance' or 'userspace' as the default governor, and no obvious way to
> select powersave, ondemand, or conservative as a default? Or was this an

Yes, ondemand and conservative may refuse to load/work on systems with
a high transition latency and that is sometimes discovered only at
runtime. This makes them not selectable as default governors.

> oversight I should cook up a patch for? Looks like the Kconfig and a bit
> of cut-n-paste in include/linux/cpufreq.h is all that's needed?

No, some more work is needed (e.g.: falling back to a different governor
if the selected fails). Thomas Renninger has posted patches on
cpufreq-devel to accomplish that.

cheers
--
mattia
:wq!
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