Re: [PATCH 3/7] idle, thermal, acpi: Remove home grown idle implementations

[Arjan van de Ven]

On 11/20/2013 9:23 AM, Thomas Gleixner wrote:
> On Wed, 20 Nov 2013, Arjan van de Ven wrote:
>
> > On 11/20/2013 8:04 AM, Peter Zijlstra wrote:
> > > This does not fully preseve existing behaviour in that the generic
> > > idle cycle function calls into the normal cpuidle governed idle
> > > routines and should thus respect things like QoS parameters and the
> > > like.
> >
> >
> > NAK on the powerclamp side.
> >
> > powerclamp MUST NOT do that....
> > it is needed to go to the deepest state no matter what
> > (this is for when your system is overheating. there is not a lot of choice
> > here... alternative is an emergency reset that the hardware does for safety)
>
> So that whole machinery falls apart when the thing which is running on
> that hot core is a while(1) loop with a higher or equal FIFO priority
> than this thread. Even if you'd run at prio 99, then there is no
> guarantee that the cpu hog does not run with prio 99 as well and due
> to FIFO and being on the CPU it's not going to let you on.

the idea was to at least give people who know what they're doing a chance to run

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