[PATCH tip/core/rcu 03/10] rculist: Add ASSERT_EXCLUSIVE_ACCESS() to __list_splice_init_rcu()

[paulmck]

From: "Paul E. McKenney" <paulmck@xxxxxxxxxx>

After the sync() in __list_splice_init_rcu(), there should be no
readers traversing the old list.  This commit therefore enlists the
help of KCSAN to verify this condition via a pair of calls to
ASSERT_EXCLUSIVE_ACCESS().

Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxx>
Cc: Marco Elver <elver@xxxxxxxxxx>
---
 include/linux/rculist.h | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/include/linux/rculist.h b/include/linux/rculist.h
index df587d1..2ebd112 100644
--- a/include/linux/rculist.h
+++ b/include/linux/rculist.h
@@ -248,6 +248,8 @@ static inline void __list_splice_init_rcu(struct list_head *list,
 	 */
 
 	sync();
+	ASSERT_EXCLUSIVE_ACCESS(*first);
+	ASSERT_EXCLUSIVE_ACCESS(*last);
 
 	/*
 	 * Readers are finished with the source list, so perform splice.
-- 
2.9.5