Commit e837d833 authored Sep 12, 2024 by Bart Van Assche Committed by Greg Kroah-Hartman Sep 13, 2024

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 <andy.shevchenko@gmail.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20240912223956.3554086-3-bvanassche@acm.org


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 96f80528

include/linux/mutex.h

+11 −0

Original line number	Diff line number	Diff line
		@@ -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) \