If might_lock() is called on a mutex, it may also potentially sleep.
Call might_sleep() in this case so that the caller is checked for both.
This is similar to the might_sleep() that is checked by the real
mutex_lock().
Signed-off-by: Chris Wilson <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Ingo Molnar <[email protected]>
---
include/linux/lockdep.h | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)
diff --git a/include/linux/lockdep.h b/include/linux/lockdep.h
index c1458fede1f9..0341e4246d00 100644
--- a/include/linux/lockdep.h
+++ b/include/linux/lockdep.h
@@ -549,9 +549,13 @@ static inline void print_irqtrace_events(struct task_struct *curr)
#define lock_map_acquire_tryread(l) lock_acquire_shared_recursive(l, 0, 1, NULL, _THIS_IP_)
#define lock_map_release(l) lock_release(l, 1, _THIS_IP_)
+#define lock_is_mutex(lock) \
+ __builtin_types_compatible_p(typeof(*lock), struct mutex)
+
#ifdef CONFIG_PROVE_LOCKING
# define might_lock(lock) \
do { \
+ might_sleep_if(lock_is_mutex(lock)); \
typecheck(struct lockdep_map *, &(lock)->dep_map); \
lock_acquire(&(lock)->dep_map, 0, 0, 0, 1, NULL, _THIS_IP_); \
lock_release(&(lock)->dep_map, 0, _THIS_IP_); \
@@ -563,7 +567,9 @@ do { \
lock_release(&(lock)->dep_map, 0, _THIS_IP_); \
} while (0)
#else
-# define might_lock(lock) do { } while (0)
+# define might_lock(lock) do { \
+ might_sleep_if(lock_is_mutex(lock)); \
+} while (0)
# define might_lock_read(lock) do { } while (0)
#endif
--
2.11.0
As kref_put_mutex() may take the mutex (on the final unreference), mark
it up with might_lock() so that the caller is unconditionally checked by
lockdep.
Signed-off-by: Chris Wilson <[email protected]>
Cc: Peter Zijlstra <[email protected]>
---
include/linux/kref.h | 1 +
1 file changed, 1 insertion(+)
diff --git a/include/linux/kref.h b/include/linux/kref.h
index e15828fd71f1..f55b73674bfb 100644
--- a/include/linux/kref.h
+++ b/include/linux/kref.h
@@ -102,6 +102,7 @@ static inline int kref_put_mutex(struct kref *kref,
void (*release)(struct kref *kref),
struct mutex *lock)
{
+ might_lock(lock);
WARN_ON(release == NULL);
if (unlikely(!atomic_add_unless(&kref->refcount, -1, 1))) {
mutex_lock(lock);
--
2.11.0