Re: [PATCH] Revert "cpuidle: Replace ktime_get() with local_clock()"

From: Peter Zijlstra
Date: Thu Apr 20 2017 - 09:49:32 EST


On Thu, Apr 20, 2017 at 04:43:45PM +0300, Ville Syrjälä wrote:
> On Thu, Apr 20, 2017 at 03:08:13PM +0200, Peter Zijlstra wrote:
> > On Thu, Apr 20, 2017 at 03:44:47PM +0300, ville.syrjala@xxxxxxxxxxxxxxx wrote:
> > > From: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>
> > >
> > > This reverts commit e93e59ce5b85e6c2b444f09fd1f707274ec066dc.
> > >
> > > The TSC stops in deeper C states,
> >
> > On some old hardware (Core2 era and before) only. You've forgotten to
> > mention what hardware you've observed problems with.
>
> Yeah, Core2 is what I used when I finally decided to bisect this. I've
> been plagued by the bogus powertop numbers on many machines, most
> likely all of them were of some older vintage.

> Tested-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>

OK, thanks. I'm currently chasing some other Core2 issue that is
somewhat related. See:

http://lkml.kernel.org/r/20170413132349.thxkwptdymsfsyxb@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

Once I have that sorted I'll post both patches.