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While at it, move setting of sg_overloaded below >>>> idle_cpu() check since an idle CPU can never be overloaded. >>>> >>>> Signed-off-by: K Prateek Nayak >>>> --- >>>> kernel/sched/fair.c | 7 ++++--- >>>> 1 file changed, 4 insertions(+), 3 deletions(-) >>>> >>>> diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c >>>> index ec2a79c8d0e7..3f36805ecdca 100644 >>>> --- a/kernel/sched/fair.c >>>> +++ b/kernel/sched/fair.c >>>> @@ -10358,9 +10358,6 @@ static inline void update_sg_lb_stats(struct lb_env *env, >>>> nr_running = rq->nr_running; >>>> sgs->sum_nr_running += nr_running; >>>> >>>> - if (nr_running > 1) >>>> - *sg_overloaded = 1; >>>> - >>>> if (cpu_overutilized(i)) >>>> *sg_overutilized = 1; >>>> >>>> @@ -10373,6 +10370,10 @@ static inline void update_sg_lb_stats(struct lb_env *env, >>>> continue; >>>> } >>>> >>>> + /* Overload indicator is only updated at root domain */ >>>> + if (!env->sd->parent && nr_running > 1) >>> >>> nit: may be worth checking local variable 1st which should be cheaper >>> than env->sd->parent >> >> What are your thoughts on passing NULL for "sg_overloaded" when calling >> update_sg_lb_stats() at non-root domains? Would it be equally cheap to >> do: >> >> if (sg_overloaded && nr_running > 1) >> *sg_overloaded = 1; > > you will have to test it twice as it is also set for misfit task Ah! True that. Local variable approach is indeed simpler. -- Thanks and Regards, Prateek > >> >>> >>> Reviewed-by: Vincent Guittot >> >> Thank you. >> >>> >>> >>>> + *sg_overloaded = 1; >>>> + >>>> #ifdef CONFIG_NUMA_BALANCING >>>> /* Only fbq_classify_group() uses this to classify NUMA groups */ >>>> if (sd_flags & SD_NUMA) { >>>> -- >>>> 2.34.1 >>>> >> >> -- >> Thanks and Regards, >> Prateek >>