Hi Kirill, On Thu, Nov 13, 2014 at 01:21:31PM +0300, Kirill Tkhai wrote: >> >>>> @@ -1185,8 +1223,9 @@ static int find_later_rq(struct task_struct *task) >> >>>> * We have to consider system topology and task affinity >> >>>> * first, then we can look for a suitable cpu. >> >>>> */ >> >>>> - cpumask_copy(later_mask, task_rq(task)->rd->span); >> >>>> - cpumask_and(later_mask, later_mask, cpu_active_mask); >> >>>> + cpumask_copy(later_mask, cpu_active_mask); >> >>>> + if (likely(task_rq(task)->online)) >> >>>> + cpumask_and(later_mask, later_mask, >> >>>> task_rq(task)->rd->span); >> >>>> cpumask_and(later_mask, later_mask, &task->cpus_allowed); >> >>>> best_cpu = cpudl_find(&task_rq(task)->rd->cpudl, >> >>>> task, later_mask); >> > Also, we should think about the following situation. >> > >> > DL task is left on dead rq. In your scheme it will be moved by the timer. >> > But what will be if somebody changes the class of the task (before timer)? >> >> I think timer will be cancelled in switched_from_dl(). > >Yeah, but nobody will move this task to alive rq. > >> >> Regards, >> Wanpeng Li >> >> > In this case the task still remains on dead rq. >> > >> > We should handle this situation in some way.
Your proposal is a great appreciated. Regards, Wanpeng Li >> > >> > Kirill >> > >> > >> > -- >> > 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/ >> > -- 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/
