Currently we waited for all cgwbs to get freed in cgwb_bdi_destroy()
which also means that writeback has been shutdown on them. Since this
wait is going away, directly shutdown writeback on cgwbs from
cgwb_bdi_destroy() to avoid live writeback structures after
bdi_unregister() has finished.
Signed-off-by: Jan Kara <jack@xxxxxxx>
---
mm/backing-dev.c | 9 +++++++++
1 file changed, 9 insertions(+)
diff --git a/mm/backing-dev.c b/mm/backing-dev.c
index 54b9e934eef4..c9623b410170 100644
--- a/mm/backing-dev.c
+++ b/mm/backing-dev.c
@@ -700,6 +700,7 @@ static void cgwb_bdi_destroy(struct backing_dev_info *bdi)
struct radix_tree_iter iter;
struct rb_node *rbn;
void **slot;
+ struct wb_writeback *wb;
WARN_ON(test_bit(WB_registered, &bdi->wb.state));
@@ -716,6 +717,14 @@ static void cgwb_bdi_destroy(struct backing_dev_info *bdi)
congested->__bdi = NULL; /* mark @congested unlinked */
}
+ while (!list_empty(&bdi->wb_list)) {
+ wb = list_first_entry(&bdi->wb_list, struct bdi_writeback,
+ bdi_node);
+ spin_unlock_irq(&cgwb_lock);
+ wb_shutdown(wb);
+ spin_lock_irq(&cgwb_lock);
+ }
+
spin_unlock_irq(&cgwb_lock);
/*
--
2.10.2
