[PATCH v2 5/8] md/raid10: switch to use md_account_bio() for io accounting

From: Yu Kuai
Date: Wed Jun 21 2023 - 04:53:33 EST


From: Yu Kuai <yukuai3@xxxxxxxxxx>

Make sure that 'active_io' will represent inflight io instead of io that
is dispatching, and io accounting from all levels will be consistent.

Signed-off-by: Yu Kuai <yukuai3@xxxxxxxxxx>
Reviewed-by: Xiao Ni <xni@xxxxxxxxxx>
---
drivers/md/raid10.c | 20 +++++++++-----------
drivers/md/raid10.h | 1 -
2 files changed, 9 insertions(+), 12 deletions(-)

diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c
index 79067769e44b..69f6d7b1e600 100644
--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -325,8 +325,6 @@ static void raid_end_bio_io(struct r10bio *r10_bio)
if (!test_bit(R10BIO_Uptodate, &r10_bio->state))
bio->bi_status = BLK_STS_IOERR;

- if (r10_bio->start_time)
- bio_end_io_acct(bio, r10_bio->start_time);
bio_endio(bio);
/*
* Wake up any possible resync thread that waits for the device
@@ -1172,7 +1170,7 @@ static bool regular_request_wait(struct mddev *mddev, struct r10conf *conf,
}

static void raid10_read_request(struct mddev *mddev, struct bio *bio,
- struct r10bio *r10_bio)
+ struct r10bio *r10_bio, bool io_accounting)
{
struct r10conf *conf = mddev->private;
struct bio *read_bio;
@@ -1243,9 +1241,10 @@ static void raid10_read_request(struct mddev *mddev, struct bio *bio,
}
slot = r10_bio->read_slot;

- if (!r10_bio->start_time &&
- blk_queue_io_stat(bio->bi_bdev->bd_disk->queue))
- r10_bio->start_time = bio_start_io_acct(bio);
+ if (io_accounting) {
+ md_account_bio(mddev, &bio);
+ r10_bio->master_bio = bio;
+ }
read_bio = bio_alloc_clone(rdev->bdev, bio, gfp, &mddev->bio_set);

r10_bio->devs[slot].bio = read_bio;
@@ -1543,8 +1542,8 @@ static void raid10_write_request(struct mddev *mddev, struct bio *bio,
r10_bio->master_bio = bio;
}

- if (blk_queue_io_stat(bio->bi_bdev->bd_disk->queue))
- r10_bio->start_time = bio_start_io_acct(bio);
+ md_account_bio(mddev, &bio);
+ r10_bio->master_bio = bio;
atomic_set(&r10_bio->remaining, 1);
md_bitmap_startwrite(mddev->bitmap, r10_bio->sector, r10_bio->sectors, 0);

@@ -1571,12 +1570,11 @@ static void __make_request(struct mddev *mddev, struct bio *bio, int sectors)
r10_bio->sector = bio->bi_iter.bi_sector;
r10_bio->state = 0;
r10_bio->read_slot = -1;
- r10_bio->start_time = 0;
memset(r10_bio->devs, 0, sizeof(r10_bio->devs[0]) *
conf->geo.raid_disks);

if (bio_data_dir(bio) == READ)
- raid10_read_request(mddev, bio, r10_bio);
+ raid10_read_request(mddev, bio, r10_bio, true);
else
raid10_write_request(mddev, bio, r10_bio);
}
@@ -2985,7 +2983,7 @@ static void handle_read_error(struct mddev *mddev, struct r10bio *r10_bio)

rdev_dec_pending(rdev, mddev);
r10_bio->state = 0;
- raid10_read_request(mddev, r10_bio->master_bio, r10_bio);
+ raid10_read_request(mddev, r10_bio->master_bio, r10_bio, false);
/*
* allow_barrier after re-submit to ensure no sync io
* can be issued while regular io pending.
diff --git a/drivers/md/raid10.h b/drivers/md/raid10.h
index 63e48b11b552..2e75e88d0802 100644
--- a/drivers/md/raid10.h
+++ b/drivers/md/raid10.h
@@ -123,7 +123,6 @@ struct r10bio {
sector_t sector; /* virtual sector number */
int sectors;
unsigned long state;
- unsigned long start_time;
struct mddev *mddev;
/*
* original bio going to /dev/mdx
--
2.39.2