With CONFIG_PREEMPT_RT disabled __mutex_init() is a function. With
CONFIG_PREEMPT_RT enabled, __mutex_init() is a macro. I assume this is why
mutex_init() is defined twice as exactly the same macro.
Prepare for introducing a new macro for mutex initialization by combining
the two identical mutex_init() definitions into a single definition. This
patch does not change any functionality because the C preprocessor expands
macros when it encounters the macro name and not when a macro definition
is encountered. See also commit bb630f9f7a7d ("locking/rtmutex: Add mutex
variant for RT").
Acked-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Signed-off-by: Bart Van Assche <bvanassche@xxxxxxx>
---
include/linux/mutex.h | 8 +-------
1 file changed, 1 insertion(+), 7 deletions(-)
diff --git a/include/linux/mutex.h b/include/linux/mutex.h
index a561c629d89f..ef617089db19 100644
--- a/include/linux/mutex.h
+++ b/include/linux/mutex.h
@@ -49,7 +49,6 @@ static inline void mutex_destroy(struct mutex *lock) {}
#endif
-#ifndef CONFIG_PREEMPT_RT
/**
* mutex_init - initialize the mutex
* @mutex: the mutex to be initialized
@@ -65,6 +64,7 @@ do { \
__mutex_init((mutex), #mutex, &__key); \
} while (0)
+#ifndef CONFIG_PREEMPT_RT
#define __MUTEX_INITIALIZER(lockname) \
{ .owner = ATOMIC_LONG_INIT(0) \
, .wait_lock = __RAW_SPIN_LOCK_UNLOCKED(lockname.wait_lock) \
@@ -111,12 +111,6 @@ do { \
__mutex_rt_init((mutex), name, key); \
} while (0)
-#define mutex_init(mutex) \
-do { \
- static struct lock_class_key __key; \
- \
- __mutex_init((mutex), #mutex, &__key); \
-} while (0)
#endif /* CONFIG_PREEMPT_RT */
#ifdef CONFIG_DEBUG_MUTEXES
