Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
blk-mq: add QUEUE_FLAG_BIO_ISSUE_TIME
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>
authored by
Yu Kuai
and committed by
Jens Axboe
ea3d1f10
1f963bdd
+12
-3
+5
block/blk-iolatency.c
+5
block/blk-iolatency.c
···
742
742
*/
743
743
enabled = atomic_read(&blkiolat->enable_cnt);
744
744
if (enabled != blkiolat->enabled) {
745
+
struct request_queue *q = blkiolat->rqos.disk->queue;
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746
unsigned int memflags;
746
747
747
748
memflags = blk_mq_freeze_queue(blkiolat->rqos.disk->queue);
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blkiolat->enabled = enabled;
750
+
if (enabled)
751
+
blk_queue_flag_set(QUEUE_FLAG_BIO_ISSUE_TIME, q);
752
+
else
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+
blk_queue_flag_clear(QUEUE_FLAG_BIO_ISSUE_TIME, q);
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blk_mq_unfreeze_queue(blkiolat->rqos.disk->queue, memflags);
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755
}
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756
}
+1
block/blk-mq-debugfs.c
+1
block/blk-mq-debugfs.c
+5
-3
block/blk-mq.c
+5
-3
block/blk-mq.c
···
396
396
#endif
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}
398
398
399
-
static inline void blk_mq_bio_issue_init(struct bio *bio)
399
+
static inline void blk_mq_bio_issue_init(struct request_queue *q,
400
+
struct bio *bio)
400
401
{
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#ifdef CONFIG_BLK_CGROUP
402
-
bio->issue_time_ns = blk_time_get_ns();
403
+
if (test_bit(QUEUE_FLAG_BIO_ISSUE_TIME, &q->queue_flags))
404
+
bio->issue_time_ns = blk_time_get_ns();
403
405
#endif
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}
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407
···
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3175
if (!bio_integrity_prep(bio))
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3176
goto queue_exit;
3179
3177
3180
-
blk_mq_bio_issue_init(bio);
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+
blk_mq_bio_issue_init(q, bio);
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if (blk_mq_attempt_bio_merge(q, bio, nr_segs))
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goto queue_exit;
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3181
+1
include/linux/blkdev.h
+1
include/linux/blkdev.h
···
657
657
QUEUE_FLAG_DISABLE_WBT_DEF, /* for sched to disable/enable wbt */
658
658
QUEUE_FLAG_NO_ELV_SWITCH, /* can't switch elevator any more */
659
659
QUEUE_FLAG_QOS_ENABLED, /* qos is enabled */
660
+
QUEUE_FLAG_BIO_ISSUE_TIME, /* record bio->issue_time_ns */
660
661
QUEUE_FLAG_MAX
661
662
};
662
663