Merge tag 'locking-urgent-2024-09-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull locking updates from Ingo Molnar:
 "lockdep:
    - Fix potential deadlock between lockdep and RCU (Zhiguo Niu)
    - Use str_plural() to address Coccinelle warning (Thorsten Blum)
    - Add debuggability enhancement (Luis Claudio R. Goncalves)

  static keys & calls:
    - Fix static_key_slow_dec() yet again (Peter Zijlstra)
    - Handle module init failure correctly in static_call_del_module()
      (Thomas Gleixner)
    - Replace pointless WARN_ON() in static_call_module_notify() (Thomas
      Gleixner)

  <linux/cleanup.h>:
    - Add usage and style documentation (Dan Williams)

  rwsems:
    - Move is_rwsem_reader_owned() and rwsem_owner() under
      CONFIG_DEBUG_RWSEMS (Waiman Long)

  atomic ops, x86:
    - Redeclare x86_32 arch_atomic64_{add,sub}() as void (Uros Bizjak)
    - Introduce the read64_nonatomic macro to x86_32 with cx8 (Uros
      Bizjak)"

Signed-off-by: Ingo Molnar <mingo@kernel.org>

* tag 'locking-urgent-2024-09-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  locking/rwsem: Move is_rwsem_reader_owned() and rwsem_owner() under CONFIG_DEBUG_RWSEMS
  jump_label: Fix static_key_slow_dec() yet again
  static_call: Replace pointless WARN_ON() in static_call_module_notify()
  static_call: Handle module init failure correctly in static_call_del_module()
  locking/lockdep: Simplify character output in seq_line()
  lockdep: fix deadlock issue between lockdep and rcu
  lockdep: Use str_plural() to fix Coccinelle warning
  cleanup: Add usage and style documentation
  lockdep: suggest the fix for "lockdep bfs error:-1" on print_bfs_bug
  locking/atomic/x86: Redeclare x86_32 arch_atomic64_{add,sub}() as void
  locking/atomic/x86: Introduce the read64_nonatomic macro to x86_32 with cx8

1 files changed, 10 insertions, 12 deletions

diff --git a/kernel/locking/rwsem.c b/kernel/locking/rwsem.c
index 5ded7dff46ef..2bbb6eca5144 100644
--- a/kernel/locking/rwsem.c
+++ b/kernel/locking/rwsem.c
@@ -181,12 +181,21 @@ static inline void rwsem_set_reader_owned(struct rw_semaphore *sem)
 	__rwsem_set_reader_owned(sem, current);
 }
 
+#ifdef CONFIG_DEBUG_RWSEMS
+/*
+ * Return just the real task structure pointer of the owner
+ */
+static inline struct task_struct *rwsem_owner(struct rw_semaphore *sem)
+{
+	return (struct task_struct *)
+		(atomic_long_read(&sem->owner) & ~RWSEM_OWNER_FLAGS_MASK);
+}
+
 /*
  * Return true if the rwsem is owned by a reader.
  */
 static inline bool is_rwsem_reader_owned(struct rw_semaphore *sem)
 {
-#ifdef CONFIG_DEBUG_RWSEMS
 	/*
 	 * Check the count to see if it is write-locked.
 	 */
@@ -194,11 +203,9 @@ static inline bool is_rwsem_reader_owned(struct rw_semaphore *sem)
 
 	if (count & RWSEM_WRITER_MASK)
 		return false;
-#endif
 	return rwsem_test_oflags(sem, RWSEM_READER_OWNED);
 }
 
-#ifdef CONFIG_DEBUG_RWSEMS
 /*
  * With CONFIG_DEBUG_RWSEMS configured, it will make sure that if there
  * is a task pointer in owner of a reader-owned rwsem, it will be the
@@ -266,15 +273,6 @@ static inline bool rwsem_write_trylock(struct rw_semaphore *sem)
 }
 
 /*
- * Return just the real task structure pointer of the owner
- */
-static inline struct task_struct *rwsem_owner(struct rw_semaphore *sem)
-{
-	return (struct task_struct *)
-		(atomic_long_read(&sem->owner) & ~RWSEM_OWNER_FLAGS_MASK);
-}
-
-/*
  * Return the real task structure pointer of the owner and the embedded
  * flags in the owner. pflags must be non-NULL.
  */