mm/backing-dev.c: use rb_entry()

To make the code clearer, use rb_entry() instead of container_of() to
deal with rbtree.

Link: http://lkml.kernel.org/r/671275de093d93ddc7c6f77ddc0d357149691a39.1484306840.git.geliangtang@gmail.com
Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Cc: Jens Axboe <axboe@fb.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 2 insertions, 2 deletions

diff --git a/mm/backing-dev.c b/mm/backing-dev.c
index 39ce616a9d71..6d861d090e9f 100644
--- a/mm/backing-dev.c
+++ b/mm/backing-dev.c
@@ -411,8 +411,8 @@ retry:
 
         while (*node != NULL) {
                 parent = *node;
-                congested = container_of(parent, struct bdi_writeback_congested,
-                                         rb_node);
+                congested = rb_entry(parent, struct bdi_writeback_congested,
+                                     rb_node);
                 if (congested->blkcg_id < blkcg_id)
                         node = &parent->rb_left;
                 else if (congested->blkcg_id > blkcg_id)