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[...] > @@ -12843,6 +12858,22 @@ static int sched_balance_newidle(struct > break; > > if (sd->flags & SD_BALANCE_NEWIDLE) { > + unsigned int weight = 1; > + > + if (sched_feat(NI_RANDOM)) { > + /* > + * Throw a 1k sided dice; and only run > + * newidle_balance according to the success > + * rate. > + */ > + u32 d1k = sched_rng() % 1024; > + weight = 1 + sd->newidle_ratio; > + if (d1k > weight) { > + update_newidle_stats(sd, 0); > + continue; > + } > + weight = (1024 + weight/2) / weight; > + } > e.g: Why 'weight = (1024 + weight/2) / weight' Thanks, -adam