on_q_ns          1874 block/blk-iocost.c 	u64 on_q_ns, rq_wait_ns;
on_q_ns          1893 block/blk-iocost.c 	on_q_ns = ktime_get_ns() - rq->alloc_time_ns;
on_q_ns          1896 block/blk-iocost.c 	if (on_q_ns <= ioc->params.qos[pidx] * NSEC_PER_USEC)