Re: [PATCH 2/4] nohz: Synchronize sleep time stats with seqlock

[Peter Zijlstra]

On Fri, Aug 16, 2013 at 07:12:09PM +0200, Frederic Weisbecker wrote:
> Or may be Peter could tell us as well. Peter, do you have a preference?

Still trying to wrap my head around it, but conceptually
get_cpu_iowait_time_us() doesn't make any kind of sense. iowait isn't
per cpu since effectively tasks that aren't running aren't assigned a
cpu (as Oleg already pointed out).

The fact that cpufreq 'needs' this just means that cpufreq is broken --
but I think I've said as much previously; cpufreq needs to stop living
in the partitioned-mp era and get dragged (kicking and screaming) into
the smp era.

I'm also not entirely clear on the 'desired' semantics here. Do we count
iowait time as idle or not?
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