bio->issue_time_ns is initialized for every bio, however, it's only used by blk-iolatency. Add a new queue_flag and only set this flag when blk-iolatency is enabled, so that extra blk_time_get_ns() can be saved for disks that blk-iolatency is not enabled. Signed-off-by: Yu Kuai <yukuai3@huawei.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
30 KiB
30 KiB