Re: [PATCH v2 md-6.14 2/5] md/md-bitmap: remove the last parameter for bimtap_ops->endwrite()

From: Xiao Ni
Date: Mon Dec 23 2024 - 02:32:16 EST

On Wed, Dec 18, 2024 at 8:21 PM <yukuai@xxxxxxxxxx> wrote:
>
> From: Yu Kuai <yukuai3@xxxxxxxxxx>
>
> It is useless, because for the case IO failed for one rdev:
>
> - If badblocks is set and rdev is not faulty, there is no need to
> mark the bit as NEEDED;


Hi Kuai

It's better to add some comments before here. Before this patch, it's
easy to understand. It needs to set bitmap bit when a write request
fails. With this patch, there are some hidden logics here. To me, it's
not easy to maintain in the future. And in man mdadm, there is no-bbl
option, so it looks like an array may not have a bad block. And I
don't know how dmraid maintain badblock. So this patch needs to be
more careful.

Regards
Xiao

> - If rdev is faulty, then mddev->degraded will be set, and we can use
> it to mard the bit as NEEDED;
>
> Signed-off-by: Yu Kuai <yukuai3@xxxxxxxxxx>
> Signed-off-by: Yu Kuai <yukuai@xxxxxxxxxx>
> ---
> drivers/md/md-bitmap.c | 19 ++++++++++---------
> drivers/md/md-bitmap.h | 2 +-
> drivers/md/raid1.c | 3 +--
> drivers/md/raid10.c | 3 +--
> drivers/md/raid5-cache.c | 3 +--
> drivers/md/raid5.c | 9 +++------
> 6 files changed, 17 insertions(+), 22 deletions(-)
>
> diff --git a/drivers/md/md-bitmap.c b/drivers/md/md-bitmap.c
> index 84fb4cc67d5e..b40a84b01085 100644
> --- a/drivers/md/md-bitmap.c
> +++ b/drivers/md/md-bitmap.c
> @@ -1726,7 +1726,7 @@ static int bitmap_startwrite(struct mddev *mddev, sector_t offset,
> }
>
> static void bitmap_endwrite(struct mddev *mddev, sector_t offset,
> - unsigned long sectors, bool success)
> + unsigned long sectors)
> {
> struct bitmap *bitmap = mddev->bitmap;
>
> @@ -1745,15 +1745,16 @@ static void bitmap_endwrite(struct mddev *mddev, sector_t offset,
> return;
> }
>
> - if (success && !bitmap->mddev->degraded &&
> - bitmap->events_cleared < bitmap->mddev->events) {
> - bitmap->events_cleared = bitmap->mddev->events;
> - bitmap->need_sync = 1;
> - sysfs_notify_dirent_safe(bitmap->sysfs_can_clear);
> - }
> -
> - if (!success && !NEEDED(*bmc))
> + if (!bitmap->mddev->degraded) {
> + if (bitmap->events_cleared < bitmap->mddev->events) {
> + bitmap->events_cleared = bitmap->mddev->events;
> + bitmap->need_sync = 1;
> + sysfs_notify_dirent_safe(
> + bitmap->sysfs_can_clear);
> + }
> + } else if (!NEEDED(*bmc)) {
> *bmc |= NEEDED_MASK;
> + }
>
> if (COUNTER(*bmc) == COUNTER_MAX)
> wake_up(&bitmap->overflow_wait);
> diff --git a/drivers/md/md-bitmap.h b/drivers/md/md-bitmap.h
> index e87a1f493d3c..31c93019c76b 100644
> --- a/drivers/md/md-bitmap.h
> +++ b/drivers/md/md-bitmap.h
> @@ -92,7 +92,7 @@ struct bitmap_operations {
> int (*startwrite)(struct mddev *mddev, sector_t offset,
> unsigned long sectors);
> void (*endwrite)(struct mddev *mddev, sector_t offset,
> - unsigned long sectors, bool success);
> + unsigned long sectors);
> bool (*start_sync)(struct mddev *mddev, sector_t offset,
> sector_t *blocks, bool degraded);
> void (*end_sync)(struct mddev *mddev, sector_t offset, sector_t *blocks);
> diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
> index 15ba7a001f30..81dff2cea0db 100644
> --- a/drivers/md/raid1.c
> +++ b/drivers/md/raid1.c
> @@ -423,8 +423,7 @@ static void close_write(struct r1bio *r1_bio)
> if (test_bit(R1BIO_BehindIO, &r1_bio->state))
> mddev->bitmap_ops->end_behind_write(mddev);
> /* clear the bitmap if all writes complete successfully */
> - mddev->bitmap_ops->endwrite(mddev, r1_bio->sector, r1_bio->sectors,
> - !test_bit(R1BIO_Degraded, &r1_bio->state));
> + mddev->bitmap_ops->endwrite(mddev, r1_bio->sector, r1_bio->sectors);
> md_write_end(mddev);
> }
>
> diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c
> index c3a93b2a26a6..3dc0170125b2 100644
> --- a/drivers/md/raid10.c
> +++ b/drivers/md/raid10.c
> @@ -429,8 +429,7 @@ static void close_write(struct r10bio *r10_bio)
> struct mddev *mddev = r10_bio->mddev;
>
> /* clear the bitmap if all writes complete successfully */
> - mddev->bitmap_ops->endwrite(mddev, r10_bio->sector, r10_bio->sectors,
> - !test_bit(R10BIO_Degraded, &r10_bio->state));
> + mddev->bitmap_ops->endwrite(mddev, r10_bio->sector, r10_bio->sectors);
> md_write_end(mddev);
> }
>
> diff --git a/drivers/md/raid5-cache.c b/drivers/md/raid5-cache.c
> index 4c7ecdd5c1f3..ba4f9577c737 100644
> --- a/drivers/md/raid5-cache.c
> +++ b/drivers/md/raid5-cache.c
> @@ -314,8 +314,7 @@ void r5c_handle_cached_data_endio(struct r5conf *conf,
> set_bit(R5_UPTODATE, &sh->dev[i].flags);
> r5c_return_dev_pending_writes(conf, &sh->dev[i]);
> conf->mddev->bitmap_ops->endwrite(conf->mddev,
> - sh->sector, RAID5_STRIPE_SECTORS(conf),
> - !test_bit(STRIPE_DEGRADED, &sh->state));
> + sh->sector, RAID5_STRIPE_SECTORS(conf));
> }
> }
> }
> diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
> index 93cc7e252dd4..6eb2841ce28c 100644
> --- a/drivers/md/raid5.c
> +++ b/drivers/md/raid5.c
> @@ -3664,8 +3664,7 @@ handle_failed_stripe(struct r5conf *conf, struct stripe_head *sh,
> }
> if (bitmap_end)
> conf->mddev->bitmap_ops->endwrite(conf->mddev,
> - sh->sector, RAID5_STRIPE_SECTORS(conf),
> - false);
> + sh->sector, RAID5_STRIPE_SECTORS(conf));
> bitmap_end = 0;
> /* and fail all 'written' */
> bi = sh->dev[i].written;
> @@ -3711,8 +3710,7 @@ handle_failed_stripe(struct r5conf *conf, struct stripe_head *sh,
> }
> if (bitmap_end)
> conf->mddev->bitmap_ops->endwrite(conf->mddev,
> - sh->sector, RAID5_STRIPE_SECTORS(conf),
> - false);
> + sh->sector, RAID5_STRIPE_SECTORS(conf));
> /* If we were in the middle of a write the parity block might
> * still be locked - so just clear all R5_LOCKED flags
> */
> @@ -4062,8 +4060,7 @@ static void handle_stripe_clean_event(struct r5conf *conf,
> wbi = wbi2;
> }
> conf->mddev->bitmap_ops->endwrite(conf->mddev,
> - sh->sector, RAID5_STRIPE_SECTORS(conf),
> - !test_bit(STRIPE_DEGRADED, &sh->state));
> + sh->sector, RAID5_STRIPE_SECTORS(conf));
> if (head_sh->batch_head) {
> sh = list_first_entry(&sh->batch_list,
> struct stripe_head,
> --
> 2.43.0
>
>