BFQ_HW_QUEUE_THRESHOLD
if (bfqd->tot_rq_in_driver + bfqd->queued <= BFQ_HW_QUEUE_THRESHOLD)
BFQ_HW_QUEUE_THRESHOLD &&
bfqd->tot_rq_in_driver < BFQ_HW_QUEUE_THRESHOLD)
bfqd->hw_tag = bfqd->max_rq_in_driver > BFQ_HW_QUEUE_THRESHOLD;