PERCPU_COUNTER_BATCH
if (attr->max_entries / 2 > num_online_cpus() * PERCPU_COUNTER_BATCH)
PERCPU_COUNTER_BATCH) >= 0;
percpu_counter_add_batch(&htab->pcount, 1, PERCPU_COUNTER_BATCH);
percpu_counter_add_batch(&htab->pcount, -1, PERCPU_COUNTER_BATCH);