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Thoughts? >> > > I suppose what you mean is to avoid the race condition between > enabling sched_cache and EQ/DE_LLC, similar to uclamp: > >         enqueue(taskA) >         // sched_cache gets enabled >         enqueue(taskB) >         dequeue(taskA) >         // Must not decrement rq->llc_pref for taskA >         dequeue(taskB) Yup! We can have enqueue(p) account_llc_enqueue(p) if (sched_cache_enabled()) p->se.llc_sched_active = true; rq->nr_llc_running += (p->preferred_llc != -1); rq->nr_pref_llc_running += (p->preferred_llc == task_llc(p)); ... dequeue(p) account_llc_dequeue(p) if (p->se.llc_sched_active) rq->nr_llc_running -= (p->preferred_llc != -1); rq->nr_pref_llc_running -= (p->preferred_llc == task_llc(p)); We can also have a single bit for "llc_sched_active" in the task_struct next to the "sched_task_hot" bit instead of using the hole in sched_entity after "sched_delayed" -- Thanks and Regards, Prateek