blk_queue_io_stat
if (!blk_queue_io_stat(req->q))
if (blk_queue_io_stat(md->queue))
if (blk_queue_io_stat(bdev->bd_disk->queue))
do_acct = blk_queue_io_stat(bio->bi_bdev->bd_disk->queue);
do_acct = blk_queue_io_stat(bio->bi_bdev->bd_disk->queue);
if (!blk_queue_io_stat(disk->queue) || blk_rq_is_passthrough(rq) ||