cpu frequency governor regression (?)

Dave Jones davej at redhat.com
Thu Dec 13 04:30:01 EST 2007


On Tue, Dec 11, 2007 at 07:52:45PM +0100, Johannes Berg wrote:
 > Hi,
 > 
 > No idea who to bother with this and maybe it's just a
 > misconfiguration... Apologies if my guesses are totally wrong.
 > 
 > I'm currently on 2.6.24-rc3 (+wireless-2.6#everything) but couldn't find
 > any patches between that and 2.6.24-rc5 that seemed relevant.
 > 
 > On my quad powermac, I'm seeing the cpufreq governor changed by a
 > hibernation cycle. My default governor is "userspace", which is driven
 > by powernowd (because the latency is too high "ondemand" doesn't like my
 > machine) but after a hibernation cycle I'm having the governor set to
 > "performance".

bizarre. It should default back to whatever CONFIG_CPU_FREQ_DEFAULT_* option
was set.  (Arguably a bug in itself, as we don't track & restore them
on resume, so if you changed from the default after booting: splat)

Why you're getting the performance governor is puzzling though.
Can you enable CONFIG_CPU_FREQ_DEBUG=y, and boot with cpufreq.debug=7
and send the log from a transition across hibernate?

Also, does /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor 
have performance in *all* the cpus?

	Dave

-- 
http://www.codemonkey.org.uk



More information about the Linuxppc-dev mailing list