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@xxxxxxxxx>
Acked-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Reviewed-by: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Signed-off-by: Bart Van Assche <bvanassche@xxxxxxx>
---
include/linux/mutex.h | 11 +++++++++++
1 file changed, 11 insertions(+)
diff --git a/include/linux/mutex.h b/include/linux/mutex.h
index ef617089db19..2bf91b57591b 100644
--- a/include/linux/mutex.h
+++ b/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) \
