Re: 3.10-rcX: cpu governor ondemand doesn't scale well after s2ram

["Toralf Förster" <toralf.foerster@gmx.de>]

The latest bisect attempt gave :

commit a66b2e503fc79fff6632d02ef5a0ee47c1d2553d
Author: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Date:   Wed May 15 21:47:17 2013 +0200

    cpufreq: Preserve sysfs files across suspend/resume

    The file permissions of cpufreq per-cpu sysfs files are not preserved
    across suspend/resume because we internally go through the CPU
    Hotplug path which reinitializes the file permissions on CPU online.

    But the user is not supposed to know that we are using CPU hotplug
    internally within suspend/resume (IOW, the kernel should not silently
    wreck the user-set file permissions across a suspend cycle).
    Therefore, we need to preserve the file permissions as they are
    across suspend/resume.

    The simplest way to achieve that is to just not touch the sysfs files
    at all - ie., just ignore the CPU hotplug notifications in the
    suspend/resume path (_FROZEN) in the cpufreq hotplug callback.

    Reported-by: Robert Jarzmik <robert.jarzmik@intel.com>
    Reported-by: Durgadoss R <durgadoss.r@intel.com>
    Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
    Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
    Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>



To get a more reliable bisect result I had to start BOINC before (4
childs each with nice -19 started)

-- 
MfG/Sincerely
Toralf Förster
pgp finger print: 7B1A 07F4 EC82 0F90 D4C2 8936 872A E508 7DB6 9DA3