[PATCH -next 27/29] md: remove mddev_suspend() and mddev_resume()

From: Yu Kuai
Date: Thu Aug 03 2023 - 09:35:43 EST


From: Yu Kuai <yukuai3@xxxxxxxxxx>

Now that mddev_suspend() and mddev_resume() is not used anywhere, remove
them, and remove 'MD_ALLOW_SB_UPDATE' and 'MD_UPDATING_SB' as well.

Signed-off-by: Yu Kuai <yukuai3@xxxxxxxxxx>
---
drivers/md/md.c | 80 -------------------------------------------------
drivers/md/md.h | 8 -----
2 files changed, 88 deletions(-)

diff --git a/drivers/md/md.c b/drivers/md/md.c
index 915a6f15d726..3f4537876cc2 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -417,74 +417,6 @@ static void md_submit_bio(struct bio *bio)
md_handle_request(mddev, bio);
}

-/* mddev_suspend makes sure no new requests are submitted
- * to the device, and that any requests that have been submitted
- * are completely handled.
- * Once mddev_detach() is called and completes, the module will be
- * completely unused.
- */
-void mddev_suspend(struct mddev *mddev)
-{
- struct md_thread *thread = rcu_dereference_protected(mddev->thread,
- lockdep_is_held(&mddev->reconfig_mutex));
-
- WARN_ON_ONCE(thread && current == thread->tsk);
-
- /* can't concurrent with __mddev_suspend() and __mddev_resume() */
- mutex_lock(&mddev->suspend_mutex);
- if (mddev->suspended++) {
- mutex_unlock(&mddev->suspend_mutex);
- return;
- }
-
- wake_up(&mddev->sb_wait);
- set_bit(MD_ALLOW_SB_UPDATE, &mddev->flags);
- percpu_ref_kill(&mddev->active_io);
-
- /*
- * TODO: cleanup 'pers->prepare_suspend after all callers are replaced
- * by __mddev_suspend().
- */
- if (mddev->pers && mddev->pers->prepare_suspend)
- mddev->pers->prepare_suspend(mddev);
-
- wait_event(mddev->sb_wait, percpu_ref_is_zero(&mddev->active_io));
- clear_bit_unlock(MD_ALLOW_SB_UPDATE, &mddev->flags);
- wait_event(mddev->sb_wait, !test_bit(MD_UPDATING_SB, &mddev->flags));
-
- del_timer_sync(&mddev->safemode_timer);
- /* restrict memory reclaim I/O during raid array is suspend */
- mddev->noio_flag = memalloc_noio_save();
-
- mutex_unlock(&mddev->suspend_mutex);
-}
-EXPORT_SYMBOL_GPL(mddev_suspend);
-
-void mddev_resume(struct mddev *mddev)
-{
- lockdep_assert_held(&mddev->reconfig_mutex);
-
- /* can't concurrent with __mddev_suspend() and __mddev_resume() */
- mutex_lock(&mddev->suspend_mutex);
- if (--mddev->suspended) {
- mutex_unlock(&mddev->suspend_mutex);
- return;
- }
-
- /* entred the memalloc scope from mddev_suspend() */
- memalloc_noio_restore(mddev->noio_flag);
-
- percpu_ref_resurrect(&mddev->active_io);
- wake_up(&mddev->sb_wait);
-
- set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
- md_wakeup_thread(mddev->thread);
- md_wakeup_thread(mddev->sync_thread); /* possibly kick off a reshape */
-
- mutex_unlock(&mddev->suspend_mutex);
-}
-EXPORT_SYMBOL_GPL(mddev_resume);
-
void __mddev_suspend(struct mddev *mddev)
{

@@ -9455,18 +9387,6 @@ static void md_start_sync(struct work_struct *ws)
*/
void md_check_recovery(struct mddev *mddev)
{
- if (test_bit(MD_ALLOW_SB_UPDATE, &mddev->flags) && mddev->sb_flags) {
- /* Write superblock - thread that called mddev_suspend()
- * holds reconfig_mutex for us.
- */
- set_bit(MD_UPDATING_SB, &mddev->flags);
- smp_mb__after_atomic();
- if (test_bit(MD_ALLOW_SB_UPDATE, &mddev->flags))
- md_update_sb(mddev, 0);
- clear_bit_unlock(MD_UPDATING_SB, &mddev->flags);
- wake_up(&mddev->sb_wait);
- }
-
if (is_md_suspended(mddev))
return;

diff --git a/drivers/md/md.h b/drivers/md/md.h
index 24adb603461d..492c5a130da3 100644
--- a/drivers/md/md.h
+++ b/drivers/md/md.h
@@ -240,10 +240,6 @@ struct md_cluster_info;
* become failed.
* @MD_HAS_PPL: The raid array has PPL feature set.
* @MD_HAS_MULTIPLE_PPLS: The raid array has multiple PPLs feature set.
- * @MD_ALLOW_SB_UPDATE: md_check_recovery is allowed to update the metadata
- * without taking reconfig_mutex.
- * @MD_UPDATING_SB: md_check_recovery is updating the metadata without
- * explicitly holding reconfig_mutex.
* @MD_NOT_READY: do_md_run() is active, so 'array_state', ust not report that
* array is ready yet.
* @MD_BROKEN: This is used to stop writes and mark array as failed.
@@ -260,8 +256,6 @@ enum mddev_flags {
MD_FAILFAST_SUPPORTED,
MD_HAS_PPL,
MD_HAS_MULTIPLE_PPLS,
- MD_ALLOW_SB_UPDATE,
- MD_UPDATING_SB,
MD_NOT_READY,
MD_BROKEN,
MD_DELETED,
@@ -802,8 +796,6 @@ extern int md_rdev_init(struct md_rdev *rdev);
extern void md_rdev_clear(struct md_rdev *rdev);

extern void md_handle_request(struct mddev *mddev, struct bio *bio);
-extern void mddev_suspend(struct mddev *mddev);
-extern void mddev_resume(struct mddev *mddev);
extern void __mddev_suspend(struct mddev *mddev);
extern void __mddev_resume(struct mddev *mddev);

--
2.39.2