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References: <20230627014332.3810102-1-linan666@huaweicloud.com>
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From:   Song Liu <song@kernel.org>
Date:   Fri, 7 Jul 2023 16:01:59 +0800
Message-ID: <CAPhsuW5cO4q+XZm=XwKzG6Npot5m5T5ECtWaXuOLU-d5st3boA@mail.gmail.com>
Subject: Re: [PATCH v2] md/raid1: prioritize adding disk to 'removed' mirror
To:     linan666@huaweicloud.com
Cc:     linux-raid@vger.kernel.org, linux-kernel@vger.kernel.org,
        linan122@huawei.com, yukuai3@huawei.com, yi.zhang@huawei.com,
        houtao1@huawei.com, yangerkun@huawei.com
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On Tue, Jun 27, 2023 at 9:44=E2=80=AFAM <linan666@huaweicloud.com> wrote:
>
> From: Li Nan <linan122@huawei.com>
>
> New disk should be added to "removed" position first instead of to be a
> replacement. Commit 6090368abcb4 ("md/raid10: prioritize adding disk to
> 'removed' mirror") has fixed this issue for raid10. Fix it for raid1 now.
>
> Signed-off-by: Li Nan <linan122@huawei.com>
> Reviewed-by: Yu Kuai <yukuai3@huawei.com>

Applied to md-next. Thanks!

Song

> ---
> Changes in v2:
>  - improve commit log.
>
>  drivers/md/raid1.c | 26 +++++++++++++++-----------
>  1 file changed, 15 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
> index 68a9e2d9985b..320bede4bfab 100644
> --- a/drivers/md/raid1.c
> +++ b/drivers/md/raid1.c
> @@ -1782,7 +1782,7 @@ static int raid1_add_disk(struct mddev *mddev, stru=
ct md_rdev *rdev)
>  {
>         struct r1conf *conf =3D mddev->private;
>         int err =3D -EEXIST;
> -       int mirror =3D 0;
> +       int mirror =3D 0, repl_slot =3D -1;
>         struct raid1_info *p;
>         int first =3D 0;
>         int last =3D conf->raid_disks - 1;
> @@ -1825,17 +1825,21 @@ static int raid1_add_disk(struct mddev *mddev, st=
ruct md_rdev *rdev)
>                         break;
>                 }
>                 if (test_bit(WantReplacement, &p->rdev->flags) &&
> -                   p[conf->raid_disks].rdev =3D=3D NULL) {
> -                       /* Add this device as a replacement */
> -                       clear_bit(In_sync, &rdev->flags);
> -                       set_bit(Replacement, &rdev->flags);
> -                       rdev->raid_disk =3D mirror;
> -                       err =3D 0;
> -                       conf->fullsync =3D 1;
> -                       rcu_assign_pointer(p[conf->raid_disks].rdev, rdev=
);
> -                       break;
> -               }
> +                   p[conf->raid_disks].rdev =3D=3D NULL && repl_slot < 0=
)
> +                       repl_slot =3D mirror;
>         }
> +
> +       if (err && repl_slot >=3D 0) {
> +               /* Add this device as a replacement */
> +               p =3D conf->mirrors + repl_slot;
> +               clear_bit(In_sync, &rdev->flags);
> +               set_bit(Replacement, &rdev->flags);
> +               rdev->raid_disk =3D repl_slot;
> +               err =3D 0;
> +               conf->fullsync =3D 1;
> +               rcu_assign_pointer(p[conf->raid_disks].rdev, rdev);
> +       }
> +
>         print_conf(conf);
>         return err;
>  }
> --
> 2.39.2
>