shrinker_id_to_index
unit = info->unit[shrinker_id_to_index(shrinker_id)];
unit = info->unit[shrinker_id_to_index(shrinker->id)];
unit = info->unit[shrinker_id_to_index(shrinker->id)];
for (index = 0; index < shrinker_id_to_index(child_info->map_nr_max); index++) {
if (index < shrinker_id_to_index(info->map_nr_max)) {