From: Yu Kuai <yuku...@huawei.com>
New mddev_resume() calls are added to synchroniza IO with array
reconfiguration, however, this introduce a regression while adding it in
md_start_sync():
1) someone set MD_RECOVERY_NEEDED first;
2) daemon thread grab reconfig_mutex, then clear MD_RECOVERY_NEEDED and
queue a new sync work;
3) daemon thread release reconfig_mutex;
4) in md_start_sync
a) check that there are spares that can be added/removed, then suspend
the array;
b) remove_and_add_spares may not be called, or called without really
add/remove spares;
c) resume the array, then set MD_RECOVERY_NEEDED again!
Loop between 2 - 4, then mddev_suspend() will be called quite often, for
consequence, normal IO will be quite slow.
Fix this problem by spliting MD_RECOVERY_NEEDED out of mddev_resume(), so
that md_start_sync() won't set such flag and hence the loop will be broken.
Fixes: bc08041b32ab ("md: suspend array in md_start_sync() if array need
reconfiguration")
Reported-and-tested-by: Janpieter Sollie <janpieter.sol...@edpnet.be>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218200
Signed-off-by: Yu Kuai <yuku...@huawei.com>
---
drivers/md/dm-raid.c | 1 +
drivers/md/md-bitmap.c | 2 ++
drivers/md/md.c | 6 +++++-
drivers/md/raid5.c | 4 ++++
4 files changed, 12 insertions(+), 1 deletion(-)
diff --git a/drivers/md/dm-raid.c b/drivers/md/dm-raid.c
index eb009d6bb03a..e9c0d70f7fe5 100644
--- a/drivers/md/dm-raid.c
+++ b/drivers/md/dm-raid.c
@@ -4059,6 +4059,7 @@ static void raid_resume(struct dm_target *ti)
clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
mddev->ro = 0;
mddev->in_sync = 0;
+ set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
mddev_unlock_and_resume(mddev);
}
}
diff --git a/drivers/md/md-bitmap.c b/drivers/md/md-bitmap.c
index 9672f75c3050..16112750ee64 100644
--- a/drivers/md/md-bitmap.c
+++ b/drivers/md/md-bitmap.c
@@ -2428,6 +2428,7 @@ location_store(struct mddev *mddev, const char *buf,
size_t len)
}
rv = 0;
out:
+ set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
mddev_unlock_and_resume(mddev);
if (rv)
return rv;
@@ -2571,6 +2572,7 @@ backlog_store(struct mddev *mddev, const char *buf,
size_t len)
if (old_mwb != backlog)
md_bitmap_update_sb(mddev->bitmap);
+ set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
mddev_unlock_and_resume(mddev);
return len;
}
diff --git a/drivers/md/md.c b/drivers/md/md.c
index 4b1e8007dd15..48a1b12f3c2c 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -515,7 +515,6 @@ void mddev_resume(struct mddev *mddev)
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 */
@@ -4146,6 +4145,7 @@ level_store(struct mddev *mddev, const char *buf, size_t
len)
md_new_event();
rv = len;
out_unlock:
+ set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
mddev_unlock_and_resume(mddev);
return rv;
}
@@ -4652,6 +4652,8 @@ new_dev_store(struct mddev *mddev, const char *buf,
size_t len)
out:
if (err)
export_rdev(rdev, mddev);
+ else
+ set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
mddev_unlock_and_resume(mddev);
if (!err)
md_new_event();
@@ -5533,6 +5535,7 @@ serialize_policy_store(struct mddev *mddev, const char
*buf, size_t len)
mddev_destroy_serial_pool(mddev, NULL);
mddev->serialize_policy = value;
unlock:
+ set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
mddev_unlock_and_resume(mddev);
return err ?: len;
}
@@ -6593,6 +6596,7 @@ static void autorun_devices(int part)
export_rdev(rdev, mddev);
}
autorun_array(mddev);
+ set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
mddev_unlock_and_resume(mddev);
}
/* on success, candidates will be empty, on error
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index 42ba3581cfea..f88f92517a18 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -6989,6 +6989,7 @@ raid5_store_stripe_size(struct mddev *mddev, const char
*page, size_t len)
mutex_unlock(&conf->cache_size_mutex);
out_unlock:
+ set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
mddev_unlock_and_resume(mddev);
return err ?: len;
}
@@ -7090,6 +7091,7 @@ raid5_store_skip_copy(struct mddev *mddev, const char
*page, size_t len)
else
blk_queue_flag_clear(QUEUE_FLAG_STABLE_WRITES, q);
}
+ set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
mddev_unlock_and_resume(mddev);
return err ?: len;
}
@@ -7169,6 +7171,7 @@ raid5_store_group_thread_cnt(struct mddev *mddev, const
char *page, size_t len)
kfree(old_groups);
}
}
+ set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
mddev_unlock_and_resume(mddev);
return err ?: len;
@@ -8920,6 +8923,7 @@ static int raid5_change_consistency_policy(struct mddev
*mddev, const char *buf)
if (!err)
md_update_sb(mddev, 1);
+ set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
mddev_unlock_and_resume(mddev);
return err;
--
2.39.2
