On 11 December 2014 at 10:14, Preeti U Murthy <[email protected]> wrote: > On 12/10/2014 06:22 PM, Viresh Kumar wrote: >> On 10 December 2014 at 18:03, Preeti U Murthy <[email protected]> >> wrote: >> >>> Right. We get an interrupt when nobody had asked for it to be delivered >>> or had asked for it to be delivered and later canceled the request. It >>> is most often in the latter situation, that there can be race >>> conditions. If these race conditions are not taken care of, they can >>> result in spurious interrupts. >> >> But the delta time will be very small then, right ? > > I was talking of the case where we get an interrupt from the clockevent > device but dont find the hrtimer to service and not really of an anomaly > in timekeeping. > For instance one of the issues that we had seen earlier wherein we > cancel the tick-sched-timer before going tickless, but since we had > programmed the clock event device to fire, we get a spurious interrupt. >
I verified this case before reporting; In my case tick_sched_timer do get cancelled before expire duration but then clk_evt_device get reprogrammed for next time node in list. __remove_hrtimer() takes care of that. And in case there is no timer in list; We shut down the clk_evt_device. Therefore no spurious interrupt in either of two possible cases. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
