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> >> - if ((unsigned int)i < nr_cpumask_bits) > >> - return i; > >> + if ((unsigned int)i < nr_cpumask_bits) { > >> + target = i; > >> + goto out; > >> + } > >> } > >> } > >> > >> i = select_idle_cpu(p, sd, has_idle_core, target); > >> if ((unsigned)i < nr_cpumask_bits) > >> - return i; > >> - > >> + target = i; > > > > Not sure about this final fallback. Is it worth doing an additional > > select_idle_smt_priority() after idle scan failed or stopped because the > > SIS_UTIL scan budget was exhausted? > > I see what you mean! We'll end up doing a: > > select_idle_smt_priority(p, target) > > at the end which might indeed be wasteful. Exactly. > > > > It seems better to jump to out only when one of these paths has actually > > selected a candidate: > > > > i = select_idle_cpu(p, sd, has_idle_core, target); > > if ((unsigned int)i < nr_cpumask_bits) { > > target = i; > > goto out; > > } > > > > The prev_aff and recent_used_cpu fallbacks can jump to "out" as well, since they > > were already verified as suitable candidates. If none of those paths succeeds, I > > think the existing final "return target" should remain unchanged. > > > > Does that make sense? > > Correct me if I'm wrong but you are suggesting to keep the current > return intact and put out label after it like: > > /* If no suitable target was found */ > return target; > > out: > if (!sched_smt_asym_active()) > return target; > > return select_idle_smt_priority(p, target); > --- > > That makes sense to me! Correct, I'm going to run some tests with this and will send a v3 later. Thanks! -Andrea