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Yes, we should update the rq->avg_idle for them. I will add it in version 2. > > Should attach_task() in kernel/sched/fair.c also call update_rq_avg_idle() > after activation? IMHO,  we should not call the update_rq_avg_idle() directly in attach_task(). In the current attach_task(), there is no information for the context(newidle, idle, busy). The attach_task() is also called in the newidle code path. But we can call the update_rq_avg_idle() in attach_tasks() with a condition check. > > Also, can update_rq_avg_idle() be placed inside activate_task() to avoid > all these? The same reason as above. Thanks Huang Shijie