[PATCH 1/3] CPU frequency scaling addon

[Holger Macht]

On Wed 23. Aug - 22:33:21, David Zeuthen wrote:
> On Tue, 2006-08-22 at 01:34 +0200, Holger Macht wrote:
> > I've attached a new version of the patch that builds and applies against
> > current HEAD.
> 
> Great, sorry for taking so long to review it. 
> 
> I've committed it with one change, 

Good.

> 
>  http://gitweb.freedesktop.org/?p=hal.git;a=commit;h=f0471f48cdb4a8c2826e6050d69e407823af15c8
> 
> to make introspection work and save some roundtrips on start up. Also,

Yes, but now the methods doesn't pop up in lshal output. However, Hibernate,
Suspend, etc methods are shown on the o.f.h.device.SystemPowerManagement
interface. So I don't know if it's a good idea that the methods on the
o.f.h.d.CPUFreq interface aren't shown... But nevermind, I just thing it's
a little bit of inconsistency ;-)

> D-Bus got standard infrastructure for invalid messages etc., so I
> changed your code to use that, see
> 
>  http://gitweb.freedesktop.org/?p=hal.git;a=commit;h=39024923e8920736221f28bb01d8ade84a0afd2e

Ok, no problem.

> 
> Oh, and, using the userspace governor works great for me. It's a bit
> chatty on the debug output though - any chance you can disable it for
> now just when running as 'userspace'? [1]

The problem is that I really need valuable debug output in case of
problems. I don't hope that they will arise, though ;-)

Hm, it uses the standard HAL_DEBUG macros. Maybe I could redefine it to
just DEBUG or something for the userspace implementation and then disable
it. And in case of problems one would have to redefine DEBUG back to
HAL_DEBUG. Any other idea?

On the other hand, the userspace governor shouldn't be used _that_
often. Does the ondemand governor not work for you?

> 
> This might be unrelated to your patch, I think it is... So.. when
> choosing the 'performance' governor, however, my Intel Core Due on my
> Macbook Pro bumps the CPU usage to a constant 2GHz on each core. Is that
> expected? Or a bug in the built-in performance governor in the kernel?

No bug, expected behaviour. Performance governor means statically maximum
frequency, and the powersave governor the contrary. Only ondemand and
userspace are for dynamic frequency adjustments.

> 
> Thanks again, Cheers,
> David

Thanks,
	Holger

> 
> [1] : ideally, some day, we'd have domains for logging so we can use
> D-Bus to poke the daemon to turn debug on / off for specific logical
> domains of all the code. So I could e.g. turn on debug output for the
> cpufreq addon and the storage addon for /dev/sdb. Or something.

Well, that would be great ;-)