md: be more careful setting MD_CHANGE_CLEAN
When MD_CHANGE_CLEAN is set we might block in md_write_start.
So we should only set it when fairly sure that something will clear
it.
There are two places where it is set so as to encourage a metadata
update to record the progress of resync/recovery. This should only
be done if the internal metadata update mechanisms are in use, which
can be tested by by inspecting '->persistent'.
Signed-off-by: NeilBrown <neilb@suse.de>
diff --git a/drivers/md/bitmap.c b/drivers/md/bitmap.c
index 1742435..4518994 100644
--- a/drivers/md/bitmap.c
+++ b/drivers/md/bitmap.c
@@ -1526,7 +1526,8 @@
atomic_read(&bitmap->mddev->recovery_active) == 0);
bitmap->mddev->curr_resync_completed = bitmap->mddev->curr_resync;
- set_bit(MD_CHANGE_CLEAN, &bitmap->mddev->flags);
+ if (bitmap->mddev->persistent)
+ set_bit(MD_CHANGE_CLEAN, &bitmap->mddev->flags);
sector &= ~((1ULL << CHUNK_BLOCK_SHIFT(bitmap)) - 1);
s = 0;
while (s < sector && s < bitmap->mddev->resync_max_sectors) {
diff --git a/drivers/md/md.c b/drivers/md/md.c
index 9007651..d636b0a 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -6753,7 +6753,8 @@
atomic_read(&mddev->recovery_active) == 0);
mddev->curr_resync_completed =
mddev->curr_resync;
- set_bit(MD_CHANGE_CLEAN, &mddev->flags);
+ if (mddev->persistent)
+ set_bit(MD_CHANGE_CLEAN, &mddev->flags);
sysfs_notify(&mddev->kobj, NULL, "sync_completed");
}