[PATCH -tip 3/3] locking/pvqspinlock: Robustify init_qspinlock_stat()

[Davidlohr Bueso]

Specifically around the debugfs file creation calls,
I have no idea if they could ever possibly fail, but
this is core code (debug aside) so lets at least
check the return value and inform anything fishy.

Signed-off-by: Davidlohr Bueso <dbueso@xxxxxxx>
---
 kernel/locking/qspinlock_stat.h | 14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/kernel/locking/qspinlock_stat.h b/kernel/locking/qspinlock_stat.h
index 72722334237a..ddcd653c942c 100644
--- a/kernel/locking/qspinlock_stat.h
+++ b/kernel/locking/qspinlock_stat.h
@@ -225,12 +225,18 @@ static int __init init_qspinlock_stat(void)
 	 * performance.
 	 */
 	for (i = 0; i < qstat_num; i++)
-		debugfs_create_file(qstat_names[i], 0400, d_qstat,
-				   (void *)(long)i, &fops_qstat);
+		if (!debugfs_create_file(qstat_names[i], 0400, d_qstat,
+					 (void *)(long)i, &fops_qstat))
+			goto fail;
+
+	if (!debugfs_create_file(qstat_names[qstat_reset_cnts], 0200, d_qstat,
+				 (void *)(long)qstat_reset_cnts, &fops_qstat))
+		goto fail;
 
-	debugfs_create_file(qstat_names[qstat_reset_cnts], 0200, d_qstat,
-			   (void *)(long)qstat_reset_cnts, &fops_qstat);
 	return 0;
+fail:
+	debugfs_remove_recursive(d_qstat);
+	return 1;
 }
 fs_initcall(init_qspinlock_stat);
 
-- 
2.8.1