On Mon, Jun 19, 2023 at 8:49 PM Yu Kuai <yukuai1@xxxxxxxxxxxxxxx> wrote:
>
> From: Yu Kuai <yukuai3@xxxxxxxxxx>
>
> Two problems can be fixed this way:
>
> 1) 'active_io' will represent inflight io instead of io that is
> dispatching.
>
> 2) If io accounting is enabled or disabled while io is still inflight,
> bio_start_io_acct() and bio_end_io_acct() is not balanced and io
> inflight counter will be leaked.
>
> Signed-off-by: Yu Kuai <yukuai3@xxxxxxxxxx>
> ---
> drivers/md/raid1.c | 14 ++++++--------
> drivers/md/raid1.h | 1 -
> 2 files changed, 6 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
> index dd25832eb045..06fa1580501f 100644
> --- a/drivers/md/raid1.c
> +++ b/drivers/md/raid1.c
> @@ -304,8 +304,6 @@ static void call_bio_endio(struct r1bio *r1_bio)
> if (!test_bit(R1BIO_Uptodate, &r1_bio->state))
> bio->bi_status = BLK_STS_IOERR;
>
> - if (blk_queue_io_stat(bio->bi_bdev->bd_disk->queue))
> - bio_end_io_acct(bio, r1_bio->start_time);
> bio_endio(bio);
> }
>
> @@ -1303,10 +1301,10 @@ static void raid1_read_request(struct mddev *mddev, struct bio *bio,
> }
>
> r1_bio->read_disk = rdisk;
> -
> - if (!r1bio_existed && blk_queue_io_stat(bio->bi_bdev->bd_disk->queue))
> - r1_bio->start_time = bio_start_io_acct(bio);
> -
> + if (!r1bio_existed) {
> + md_account_bio(mddev, &bio);
> + r1_bio->master_bio = bio;
> + }
> read_bio = bio_alloc_clone(mirror->rdev->bdev, bio, gfp,
> &mddev->bio_set);
>
> @@ -1500,8 +1498,8 @@ static void raid1_write_request(struct mddev *mddev, struct bio *bio,
> r1_bio->sectors = max_sectors;
> }
>
> - if (blk_queue_io_stat(bio->bi_bdev->bd_disk->queue))
> - r1_bio->start_time = bio_start_io_acct(bio);
> + md_account_bio(mddev, &bio);
> + r1_bio->master_bio = bio;
> atomic_set(&r1_bio->remaining, 1);
> atomic_set(&r1_bio->behind_remaining, 0);
>
> diff --git a/drivers/md/raid1.h b/drivers/md/raid1.h
> index 468f189da7a0..14d4211a123a 100644
> --- a/drivers/md/raid1.h
> +++ b/drivers/md/raid1.h
> @@ -157,7 +157,6 @@ struct r1bio {
> sector_t sector;
> int sectors;
> unsigned long state;
> - unsigned long start_time;
> struct mddev *mddev;
> /*
> * original bio going to /dev/mdx
> --
> 2.39.2
>
Hi Kuai
After this patch, raid1 will have one more memory allocation in the
I/O path. Not sure if it can affect performance. Beside this, the
patch is good for me.
Reviewed-by: Xiao Ni <xni@xxxxxxxxxx>
