kevin/linux
1
Fork 0
Code

locking/mutex: Define mutex_init() once

Browse Source 
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 bb630f9f7a ("locking/rtmutex: Add mutex
variant for RT").

Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
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/20240912223956.3554086-2-bvanassche@acm.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Bart Van Assche 2024-09-12 15:39:54 -07:00 committed by Greg Kroah-Hartman
parent 2193ede180
commit 96f8052822
1 changed files with 1 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
include/linux/mutex.h
View File

@ -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