[RESEND PATCH v2 1/2] locking/lockdep: Provide lockdep_assert{,_once}() helpers

From: Desmond Cheong Zhi Xi
Date: Mon Aug 02 2021 - 07:01:19 EST


From: Peter Zijlstra <peterz@xxxxxxxxxxxxx>

Extract lockdep_assert{,_once}() helpers to more easily write composite
assertions like, for example:

lockdep_assert(lockdep_is_held(&drm_device.master_mutex) ||
lockdep_is_held(&drm_file.master_lookup_lock));

Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Signed-off-by: Desmond Cheong Zhi Xi <desmondcheongzx@xxxxxxxxx>
Acked-by: Boqun Feng <boqun.feng@xxxxxxxxx>
Acked-by: Waiman Long <longman@xxxxxxxxxx>
Acked-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
---
include/linux/lockdep.h | 41 +++++++++++++++++++++--------------------
1 file changed, 21 insertions(+), 20 deletions(-)

diff --git a/include/linux/lockdep.h b/include/linux/lockdep.h
index 5cf387813754..9fe165beb0f9 100644
--- a/include/linux/lockdep.h
+++ b/include/linux/lockdep.h
@@ -306,31 +306,29 @@ extern void lock_unpin_lock(struct lockdep_map *lock, struct pin_cookie);

#define lockdep_depth(tsk) (debug_locks ? (tsk)->lockdep_depth : 0)

-#define lockdep_assert_held(l) do { \
- WARN_ON(debug_locks && \
- lockdep_is_held(l) == LOCK_STATE_NOT_HELD); \
- } while (0)
+#define lockdep_assert(cond) \
+ do { WARN_ON(debug_locks && !(cond)); } while (0)

-#define lockdep_assert_not_held(l) do { \
- WARN_ON(debug_locks && \
- lockdep_is_held(l) == LOCK_STATE_HELD); \
- } while (0)
+#define lockdep_assert_once(cond) \
+ do { WARN_ON_ONCE(debug_locks && !(cond)); } while (0)

-#define lockdep_assert_held_write(l) do { \
- WARN_ON(debug_locks && !lockdep_is_held_type(l, 0)); \
- } while (0)
+#define lockdep_assert_held(l) \
+ lockdep_assert(lockdep_is_held(l) != LOCK_STATE_NOT_HELD)

-#define lockdep_assert_held_read(l) do { \
- WARN_ON(debug_locks && !lockdep_is_held_type(l, 1)); \
- } while (0)
+#define lockdep_assert_not_held(l) \
+ lockdep_assert(lockdep_is_held(l) != LOCK_STATE_HELD)

-#define lockdep_assert_held_once(l) do { \
- WARN_ON_ONCE(debug_locks && !lockdep_is_held(l)); \
- } while (0)
+#define lockdep_assert_held_write(l) \
+ lockdep_assert(lockdep_is_held_type(l, 0))

-#define lockdep_assert_none_held_once() do { \
- WARN_ON_ONCE(debug_locks && current->lockdep_depth); \
- } while (0)
+#define lockdep_assert_held_read(l) \
+ lockdep_assert(lockdep_is_held_type(l, 1))
+
+#define lockdep_assert_held_once(l) \
+ lockdep_assert_once(lockdep_is_held(l) != LOCK_STATE_NOT_HELD)
+
+#define lockdep_assert_none_held_once() \
+ lockdep_assert_once(!current->lockdep_depth)

#define lockdep_recursing(tsk) ((tsk)->lockdep_recursion)

@@ -407,6 +405,9 @@ extern int lock_is_held(const void *);
extern int lockdep_is_held(const void *);
#define lockdep_is_held_type(l, r) (1)

+#define lockdep_assert(c) do { } while (0)
+#define lockdep_assert_once(c) do { } while (0)
+
#define lockdep_assert_held(l) do { (void)(l); } while (0)
#define lockdep_assert_not_held(l) do { (void)(l); } while (0)
#define lockdep_assert_held_write(l) do { (void)(l); } while (0)
--
2.25.1