[PATCH tip/core/rcu 4/7] userfaultfd: Replace spin_is_locked() with lockdep

From: "Paul E. McKenney" <paulmck@linux.ibm.com>
To: linux-kernel@vger.kernel.org
Cc: mingo@kernel.org, jiangshanlai@gmail.com, dipankar@in.ibm.com,
	akpm@linux-foundation.org, mathieu.desnoyers@efficios.com,
	josh@joshtriplett.org, tglx@linutronix.de, peterz@infradead.org,
	rostedt@goodmis.org, dhowells@redhat.com, edumazet@google.com,
	fweisbec@gmail.com, oleg@redhat.com, joel@joelfernandes.org,
	Lance Roy <ldr709@gmail.com>,
	Alexander Viro <viro@zeniv.linux.org.uk>,
	linux-fsdevel@vger.kernel.org,
	"Paul E . McKenney" <paulmck@linux.ibm.com>
Subject: [PATCH tip/core/rcu 4/7] userfaultfd: Replace spin_is_locked() with lockdep
Date: Sun, 11 Nov 2018 12:04:40 -0800	[thread overview]
Message-ID: <20181111200443.10772-4-paulmck@linux.ibm.com> (raw)
In-Reply-To: <20181111200421.GA10551@linux.ibm.com>

From: Lance Roy <ldr709@gmail.com>

lockdep_assert_held() is better suited to checking locking requirements,
since it only checks if the current thread holds the lock regardless of
whether someone else does. This is also a step towards possibly removing
spin_is_locked().

Signed-off-by: Lance Roy <ldr709@gmail.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: <linux-fsdevel@vger.kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
---
 fs/userfaultfd.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/userfaultfd.c b/fs/userfaultfd.c
index 356d2b8568c1..681881dc8a9d 100644
--- a/fs/userfaultfd.c
+++ b/fs/userfaultfd.c
@@ -926,7 +926,7 @@ static inline struct userfaultfd_wait_queue *find_userfault_in(
 	wait_queue_entry_t *wq;
 	struct userfaultfd_wait_queue *uwq;
 
-	VM_BUG_ON(!spin_is_locked(&wqh->lock));
+	lockdep_assert_held(&wqh->lock);
 
 	uwq = NULL;
 	if (!waitqueue_active(wqh))
-- 
2.17.1

