Re: [PATCH 2/4] timer: relax tick stop in idle entry

Peter Zijlstra
2015-11-17T10:25:05Z

On Mon, Nov 16, 2015 at 09:04:03PM -0800, Paul E. McKenney wrote:
> On Mon, Nov 16, 2015 at 06:57:14PM -0800, Arjan van de Ven wrote:
> > On 11/16/2015 6:53 PM, Paul E. McKenney wrote:
> > >Fair point. When in the five-jiffy throttling state, what can wake up
> > >a CPU? In an earlier version of this proposal, the answer was "nothing",
> > >but maybe that has changed.
> >
> > device interrupts are likely to wake the cpus.
>
> OK, that I cannot help you with. But presumably if the interrupt handler
> does a wakeup (or similar), that is deferred to the end of the throttling
> interval? Timers are also deferred, including hrtimers?

This throttling thing only throttles 'normal' tasks, real-time tasks
will still run.