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References: <20240124091421.1261579-1-yukuai3@huawei.com> <20240124091421.1261579-6-yukuai3@huawei.com>
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From: Xiao Ni <xni@redhat.com>
Date: Thu, 25 Jan 2024 15:51:08 +0800
Message-ID: <CALTww2_hG2_YL1v-d0=uv2=bVzJ2wwpSJyQdBBGMCBx79bot-Q@mail.gmail.com>
Subject: Re: [PATCH v2 05/11] md: export helpers to stop sync_thread
To: Yu Kuai <yukuai3@huawei.com>
Cc: agk@redhat.com, snitzer@kernel.org, mpatocka@redhat.com, 
	dm-devel@lists.linux.dev, song@kernel.org, jbrassow@f14.redhat.com, 
	neilb@suse.de, heinzm@redhat.com, shli@fb.com, akpm@osdl.org, 
	linux-kernel@vger.kernel.org, linux-raid@vger.kernel.org, 
	yukuai1@huaweicloud.com, yi.zhang@huawei.com, yangerkun@huawei.com
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On Wed, Jan 24, 2024 at 5:19=E2=80=AFPM Yu Kuai <yukuai3@huawei.com> wrote:
>
> The new heleprs will be used in dm-raid in later patches to fix
> regressions and prevent calling md_reap_sync_thread() directly.
>
> Signed-off-by: Yu Kuai <yukuai3@huawei.com>
> ---
>  drivers/md/md.c | 41 +++++++++++++++++++++++++++++++++++++----
>  drivers/md/md.h |  3 +++
>  2 files changed, 40 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/md/md.c b/drivers/md/md.c
> index 6c5d0a372927..90cf31b53804 100644
> --- a/drivers/md/md.c
> +++ b/drivers/md/md.c
> @@ -4915,30 +4915,63 @@ static void stop_sync_thread(struct mddev *mddev,=
 bool locked, bool check_seq)
>                 mddev_lock_nointr(mddev);
>  }
>
> -static void idle_sync_thread(struct mddev *mddev)
> +void md_idle_sync_thread(struct mddev *mddev)
>  {
> +       lockdep_assert_held(mddev->reconfig_mutex);
> +

Hi Kuai

There is a building error. It should give a pointer to
lockdep_assert_held. And same with the other two places in this patch.

Regards
Xiao

>         mutex_lock(&mddev->sync_mutex);
>         clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
> +       stop_sync_thread(mddev, true, true);
> +       mutex_unlock(&mddev->sync_mutex);
> +}
> +EXPORT_SYMBOL_GPL(md_idle_sync_thread);
> +
> +void md_frozen_sync_thread(struct mddev *mddev)
> +{
> +       lockdep_assert_held(mddev->reconfig_mutex);
> +
> +       mutex_lock(&mddev->sync_mutex);
> +       set_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
> +       stop_sync_thread(mddev, true, false);
> +       mutex_unlock(&mddev->sync_mutex);
> +}
> +EXPORT_SYMBOL_GPL(md_frozen_sync_thread);
>
> +void md_unfrozen_sync_thread(struct mddev *mddev)
> +{
> +       lockdep_assert_held(mddev->reconfig_mutex);
> +
> +       mutex_lock(&mddev->sync_mutex);
> +       clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
> +       set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
> +       md_wakeup_thread(mddev->thread);
> +       sysfs_notify_dirent_safe(mddev->sysfs_action);
> +       mutex_unlock(&mddev->sync_mutex);
> +}
> +EXPORT_SYMBOL_GPL(md_unfrozen_sync_thread);
> +
> +static void idle_sync_thread(struct mddev *mddev)
> +{
>         if (mddev_lock(mddev)) {
>                 mutex_unlock(&mddev->sync_mutex);
>                 return;
>         }
>
> +       mutex_lock(&mddev->sync_mutex);
> +       clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
>         stop_sync_thread(mddev, false, true);
>         mutex_unlock(&mddev->sync_mutex);
>  }
>
>  static void frozen_sync_thread(struct mddev *mddev)
>  {
> -       mutex_lock(&mddev->sync_mutex);
> -       set_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
> -
>         if (mddev_lock(mddev)) {
>                 mutex_unlock(&mddev->sync_mutex);
>                 return;
>         }
>
> +       mutex_lock(&mddev->sync_mutex);
> +       set_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
>         stop_sync_thread(mddev, false, false);
>         mutex_unlock(&mddev->sync_mutex);
>  }
> diff --git a/drivers/md/md.h b/drivers/md/md.h
> index 8d881cc59799..437ab70ce79b 100644
> --- a/drivers/md/md.h
> +++ b/drivers/md/md.h
> @@ -781,6 +781,9 @@ extern void md_rdev_clear(struct md_rdev *rdev);
>  extern void md_handle_request(struct mddev *mddev, struct bio *bio);
>  extern int mddev_suspend(struct mddev *mddev, bool interruptible);
>  extern void mddev_resume(struct mddev *mddev);
> +extern void md_idle_sync_thread(struct mddev *mddev);
> +extern void md_frozen_sync_thread(struct mddev *mddev);
> +extern void md_unfrozen_sync_thread(struct mddev *mddev);
>
>  extern void md_reload_sb(struct mddev *mddev, int raid_disk);
>  extern void md_update_sb(struct mddev *mddev, int force);
> --
> 2.39.2
>