2019-11-04 17:39:42

by Daniel Vetter

[permalink] [raw]
Subject: [PATCH 2/3] lockdep: add might_lock_nested()

Necessary to annotate functions where we might acquire a
mutex_lock_nested() or similar. Needed by i915.

Acked-by: Peter Zijlstra (Intel) <[email protected]>
Signed-off-by: Daniel Vetter <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Will Deacon <[email protected]>
Cc: [email protected]
---
include/linux/lockdep.h | 8 ++++++++
1 file changed, 8 insertions(+)

diff --git a/include/linux/lockdep.h b/include/linux/lockdep.h
index e0eca94e58c8..c4155436e6fc 100644
--- a/include/linux/lockdep.h
+++ b/include/linux/lockdep.h
@@ -628,6 +628,13 @@ do { \
lock_acquire(&(lock)->dep_map, 0, 0, 1, 1, NULL, _THIS_IP_); \
lock_release(&(lock)->dep_map, 0, _THIS_IP_); \
} while (0)
+# define might_lock_nested(lock, subclass) \
+do { \
+ typecheck(struct lockdep_map *, &(lock)->dep_map); \
+ lock_acquire(&(lock)->dep_map, subclass, 0, 1, 1, NULL, \
+ _THIS_IP_); \
+ lock_release(&(lock)->dep_map, 0, _THIS_IP_); \
+} while (0)

#define lockdep_assert_irqs_enabled() do { \
WARN_ONCE(debug_locks && !current->lockdep_recursion && \
@@ -650,6 +657,7 @@ do { \
#else
# define might_lock(lock) do { } while (0)
# define might_lock_read(lock) do { } while (0)
+# define might_lock_nested(lock, subclass) do { } while (0)
# define lockdep_assert_irqs_enabled() do { } while (0)
# define lockdep_assert_irqs_disabled() do { } while (0)
# define lockdep_assert_in_irq() do { } while (0)
--
2.24.0.rc2