[PATCH] bdi: show error log when fail to create bdi debugfs entry

[weiping zhang]

bdi debugfs dir/file may create fail, add error log here.

Signed-off-by: weiping zhang <zhangweip...@didichuxing.com>
---
 mm/backing-dev.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/mm/backing-dev.c b/mm/backing-dev.c
index b5f940c..9117c21 100644
--- a/mm/backing-dev.c
+++ b/mm/backing-dev.c
@@ -885,7 +885,8 @@ int bdi_register_va(struct backing_dev_info *bdi, const 
char *fmt, va_list args)
        cgwb_bdi_register(bdi);
        bdi->dev = dev;
 
-       bdi_debug_register(bdi, dev_name(dev));
+        if (bdi_debug_register(bdi, dev_name(dev)))
+                pr_warn("blkdev %s create bdi debugfs failed\n", 
dev_name(dev));
        set_bit(WB_registered, &bdi->wb.state);
 
        spin_lock_bh(&bdi_lock);
-- 
2.9.4