diff options
| author | Mike Snitzer <snitzer@redhat.com> | 2022-01-28 10:58:41 -0500 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2022-01-28 12:28:15 -0700 |
| commit | b879f915bc48a18d4f4462729192435bb0f17052 (patch) | |
| tree | a6872f00546c3ee5ae32a73dadc02712a7c27b65 | |
| parent | f524d9c95fab54783d0038f7a3e8c014d5b56857 (diff) | |
dm: properly fix redundant bio-based IO accounting
Record the start_time for a bio but defer the starting block core's IO
accounting until after IO is submitted using bio_start_io_acct_time().
This approach avoids the need to mess around with any of the
individual IO stats in response to a bio_split() that follows bio
submission.
Reported-by: Bud Brown <bubrown@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: stable@vger.kernel.org
Depends-on: e45c47d1f94e ("block: add bio_start_io_acct_time() to control start_time")
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Link: https://lore.kernel.org/r/20220128155841.39644-4-snitzer@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
| -rw-r--r-- | drivers/md/dm.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/drivers/md/dm.c b/drivers/md/dm.c index 9849114b3c08..dcbd6d201619 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -489,7 +489,7 @@ static void start_io_acct(struct dm_io *io) struct mapped_device *md = io->md; struct bio *bio = io->orig_bio; - io->start_time = bio_start_io_acct(bio); + bio_start_io_acct_time(bio, io->start_time); if (unlikely(dm_stats_used(&md->stats))) dm_stats_account_io(&md->stats, bio_data_dir(bio), bio->bi_iter.bi_sector, bio_sectors(bio), @@ -535,7 +535,7 @@ static struct dm_io *alloc_io(struct mapped_device *md, struct bio *bio) io->md = md; spin_lock_init(&io->endio_lock); - start_io_acct(io); + io->start_time = jiffies; return io; } @@ -1482,6 +1482,7 @@ static void __split_and_process_bio(struct mapped_device *md, submit_bio_noacct(bio); } } + start_io_acct(ci.io); /* drop the extra reference count */ dm_io_dec_pending(ci.io, errno_to_blk_status(error)); |