[PATCH v2] md: cleanup pers->prepare_suspend()

From: Yu Kuai
Date: Sun Oct 15 2023 - 22:06:47 EST


From: Yu Kuai <yukuai3@xxxxxxxxxx>

pers->prepare_suspend() is not used anymore and can be removed.

Reverts following three commit:

- commit 431e61257d63 ("md: export md_is_rdwr() and is_md_suspended()")
- commit 3e00777d5157 ("md: add a new api prepare_suspend() in
md_personality")
- commit 868bba54a3bc ("md/raid5: fix a deadlock in the case that reshape
is interrupted")

Signed-off-by: Yu Kuai <yukuai3@xxxxxxxxxx>
---
Changes in v2:
- fix a conflict that is caused from my local branch.

drivers/md/md.c | 17 ++++++++++++++++-
drivers/md/md.h | 18 ------------------
drivers/md/raid5.c | 44 +-------------------------------------------
3 files changed, 17 insertions(+), 62 deletions(-)

diff --git a/drivers/md/md.c b/drivers/md/md.c
index fa6fe1664e78..68f3bb6e89cb 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -91,6 +91,18 @@ static void mddev_detach(struct mddev *mddev);
static void export_rdev(struct md_rdev *rdev, struct mddev *mddev);
static void md_wakeup_thread_directly(struct md_thread __rcu *thread);

+enum md_ro_state {
+ MD_RDWR,
+ MD_RDONLY,
+ MD_AUTO_READ,
+ MD_MAX_STATE
+};
+
+static bool md_is_rdwr(struct mddev *mddev)
+{
+ return (mddev->ro == MD_RDWR);
+}
+
/*
* Default number of read corrections we'll attempt on an rdev
* before ejecting it from the array. We divide the read error
@@ -333,6 +345,10 @@ EXPORT_SYMBOL_GPL(md_new_event);
static LIST_HEAD(all_mddevs);
static DEFINE_SPINLOCK(all_mddevs_lock);

+static bool is_md_suspended(struct mddev *mddev)
+{
+ return percpu_ref_is_dying(&mddev->active_io);
+}
/* Rather than calling directly into the personality make_request function,
* IO requests come here first so that we can check if the device is
* being suspended pending a reconfiguration.
@@ -9144,7 +9160,6 @@ void md_do_sync(struct md_thread *thread)
spin_unlock(&mddev->lock);

wake_up(&resync_wait);
- wake_up(&mddev->sb_wait);
md_wakeup_thread(mddev->thread);
return;
}
diff --git a/drivers/md/md.h b/drivers/md/md.h
index 55d01d431418..20f3f96cf4c1 100644
--- a/drivers/md/md.h
+++ b/drivers/md/md.h
@@ -565,23 +565,6 @@ enum recovery_flags {
MD_RESYNCING_REMOTE, /* remote node is running resync thread */
};

-enum md_ro_state {
- MD_RDWR,
- MD_RDONLY,
- MD_AUTO_READ,
- MD_MAX_STATE
-};
-
-static inline bool md_is_rdwr(struct mddev *mddev)
-{
- return (mddev->ro == MD_RDWR);
-}
-
-static inline bool is_md_suspended(struct mddev *mddev)
-{
- return percpu_ref_is_dying(&mddev->active_io);
-}
-
static inline int __must_check mddev_lock(struct mddev *mddev)
{
return mutex_lock_interruptible(&mddev->reconfig_mutex);
@@ -641,7 +624,6 @@ struct md_personality
int (*start_reshape) (struct mddev *mddev);
void (*finish_reshape) (struct mddev *mddev);
void (*update_reshape_pos) (struct mddev *mddev);
- void (*prepare_suspend) (struct mddev *mddev);
/* quiesce suspends or resumes internal processing.
* 1 - stop new actions and wait for action io to complete
* 0 - return to normal behaviour
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index 36ca6db37153..ad6d5138a6bd 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -5907,19 +5907,6 @@ static int add_all_stripe_bios(struct r5conf *conf,
return ret;
}

-static bool reshape_inprogress(struct mddev *mddev)
-{
- return test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery) &&
- test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) &&
- !test_bit(MD_RECOVERY_DONE, &mddev->recovery) &&
- !test_bit(MD_RECOVERY_INTR, &mddev->recovery);
-}
-
-static bool reshape_disabled(struct mddev *mddev)
-{
- return is_md_suspended(mddev) || !md_is_rdwr(mddev);
-}
-
static enum stripe_result make_stripe_request(struct mddev *mddev,
struct r5conf *conf, struct stripe_request_ctx *ctx,
sector_t logical_sector, struct bio *bi)
@@ -5951,8 +5938,7 @@ static enum stripe_result make_stripe_request(struct mddev *mddev,
if (ahead_of_reshape(mddev, logical_sector,
conf->reshape_safe)) {
spin_unlock_irq(&conf->device_lock);
- ret = STRIPE_SCHEDULE_AND_RETRY;
- goto out;
+ return STRIPE_SCHEDULE_AND_RETRY;
}
}
spin_unlock_irq(&conf->device_lock);
@@ -6031,15 +6017,6 @@ static enum stripe_result make_stripe_request(struct mddev *mddev,

out_release:
raid5_release_stripe(sh);
-out:
- if (ret == STRIPE_SCHEDULE_AND_RETRY && !reshape_inprogress(mddev) &&
- reshape_disabled(mddev)) {
- bi->bi_status = BLK_STS_IOERR;
- ret = STRIPE_FAIL;
- pr_err("md/raid456:%s: io failed across reshape position while reshape can't make progress.\n",
- mdname(mddev));
- }
-
return ret;
}

@@ -8924,22 +8901,6 @@ static int raid5_start(struct mddev *mddev)
return r5l_start(conf->log);
}

-static void raid5_prepare_suspend(struct mddev *mddev)
-{
- struct r5conf *conf = mddev->private;
-
- wait_event(mddev->sb_wait, !reshape_inprogress(mddev) ||
- percpu_ref_is_zero(&mddev->active_io));
- if (percpu_ref_is_zero(&mddev->active_io))
- return;
-
- /*
- * Reshape is not in progress, and array is suspended, io that is
- * waiting for reshpape can never be done.
- */
- wake_up(&conf->wait_for_overlap);
-}
-
static struct md_personality raid6_personality =
{
.name = "raid6",
@@ -8960,7 +8921,6 @@ static struct md_personality raid6_personality =
.check_reshape = raid6_check_reshape,
.start_reshape = raid5_start_reshape,
.finish_reshape = raid5_finish_reshape,
- .prepare_suspend = raid5_prepare_suspend,
.quiesce = raid5_quiesce,
.takeover = raid6_takeover,
.change_consistency_policy = raid5_change_consistency_policy,
@@ -8985,7 +8945,6 @@ static struct md_personality raid5_personality =
.check_reshape = raid5_check_reshape,
.start_reshape = raid5_start_reshape,
.finish_reshape = raid5_finish_reshape,
- .prepare_suspend = raid5_prepare_suspend,
.quiesce = raid5_quiesce,
.takeover = raid5_takeover,
.change_consistency_policy = raid5_change_consistency_policy,
@@ -9011,7 +8970,6 @@ static struct md_personality raid4_personality =
.check_reshape = raid5_check_reshape,
.start_reshape = raid5_start_reshape,
.finish_reshape = raid5_finish_reshape,
- .prepare_suspend = raid5_prepare_suspend,
.quiesce = raid5_quiesce,
.takeover = raid4_takeover,
.change_consistency_policy = raid5_change_consistency_policy,
--
2.39.2