locking/mutex: Introduce mutex_init_with_key()

The following pattern occurs 5 times in kernel drivers:

	lockdep_register_key(key);
	__mutex_init(mutex, name, key);

In several cases the 'name' argument matches #mutex. Hence, introduce
the mutex_init_with_key() macro. This macro derives the 'name' argument
from the 'mutex' argument.

Suggested-by: Andy Shevchenko <[email protected]>
Acked-by: Peter Zijlstra (Intel) <[email protected]>
Reviewed-by: Andy Shevchenko <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Ingo Molnar <[email protected]>
Signed-off-by: Bart Van Assche <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

Author: bvanassche

include/linux/mutex.h

@@ -64,6 +64,17 @@ do {									\
 	__mutex_init((mutex), #mutex, &__key);				\
 } while (0)
 
+/**
+ * mutex_init_with_key - initialize a mutex with a given lockdep key
+ * @mutex: the mutex to be initialized
+ * @key: the lockdep key to be associated with the mutex
+ *
+ * Initialize the mutex to the unlocked state.
+ *
+ * It is not allowed to initialize an already locked mutex.
+ */
+#define mutex_init_with_key(mutex, key) __mutex_init((mutex), #mutex, (key))
+
 #ifndef CONFIG_PREEMPT_RT
 #define __MUTEX_INITIALIZER(lockname) \
 		{ .owner = ATOMIC_LONG_INIT(0) \