On Tue, 17 Nov 2015 11:24:49 +0100 Peter Zijlstra <pet...@infradead.org> wrote:
> 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. As an optimization or option, it might be useful to further defer the next timer interrupt if it falls within the idle injection period. But I guess we don't know if that timer belongs to a normal task or rt. Also we there could be more than one 'next' timer interrupts fall into that injection idle period. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/