From: Nikolay Borisov <nborisov@suse.com>
Date: Wed, 27 Jun 2018 13:38:23 +0000 (+0300)
Subject: btrfs: Document locking requirement via lockdep_assert_held
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=07e21c4dad42be8d2a6b8cd0b98cf8e6931e12fd;p=linux.git

btrfs: Document locking requirement via lockdep_assert_held

Remove stale comment since there is no longer an eb->eb_lock and
document the locking expectation with a lockdep_assert_held statement.
No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
---

diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 6a4013ddcf733..5ab401f796838 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -5066,9 +5066,10 @@ static inline void btrfs_release_extent_buffer_rcu(struct rcu_head *head)
 	__free_extent_buffer(eb);
 }
 
-/* Expects to have eb->eb_lock already held */
 static int release_extent_buffer(struct extent_buffer *eb)
 {
+	lockdep_assert_held(&eb->refs_lock);
+
 	WARN_ON(atomic_read(&eb->refs) == 0);
 	if (atomic_dec_and_test(&eb->refs)) {
 		if (test_and_clear_bit(EXTENT_BUFFER_IN_TREE, &eb->bflags)) {