xref: /linux/kernel/locking/mutex.h (revision 4b132aacb0768ac1e652cf517097ea6f237214b9)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Mutexes: blocking mutual exclusion locks
4  *
5  * started by Ingo Molnar:
6  *
7  *  Copyright (C) 2004, 2005, 2006 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
8  */
9 
10 /*
11  * This is the control structure for tasks blocked on mutex, which resides
12  * on the blocked task's kernel stack:
13  */
14 struct mutex_waiter {
15 	struct list_head	list;
16 	struct task_struct	*task;
17 	struct ww_acquire_ctx	*ww_ctx;
18 #ifdef CONFIG_DEBUG_MUTEXES
19 	void			*magic;
20 #endif
21 };
22 
23 #ifdef CONFIG_DEBUG_MUTEXES
24 extern void debug_mutex_lock_common(struct mutex *lock,
25 				    struct mutex_waiter *waiter);
26 extern void debug_mutex_wake_waiter(struct mutex *lock,
27 				    struct mutex_waiter *waiter);
28 extern void debug_mutex_free_waiter(struct mutex_waiter *waiter);
29 extern void debug_mutex_add_waiter(struct mutex *lock,
30 				   struct mutex_waiter *waiter,
31 				   struct task_struct *task);
32 extern void debug_mutex_remove_waiter(struct mutex *lock, struct mutex_waiter *waiter,
33 				      struct task_struct *task);
34 extern void debug_mutex_unlock(struct mutex *lock);
35 extern void debug_mutex_init(struct mutex *lock, const char *name,
36 			     struct lock_class_key *key);
37 #else /* CONFIG_DEBUG_MUTEXES */
38 # define debug_mutex_lock_common(lock, waiter)		do { } while (0)
39 # define debug_mutex_wake_waiter(lock, waiter)		do { } while (0)
40 # define debug_mutex_free_waiter(waiter)		do { } while (0)
41 # define debug_mutex_add_waiter(lock, waiter, ti)	do { } while (0)
42 # define debug_mutex_remove_waiter(lock, waiter, ti)	do { } while (0)
43 # define debug_mutex_unlock(lock)			do { } while (0)
44 # define debug_mutex_init(lock, name, key)		do { } while (0)
45 #endif /* !CONFIG_DEBUG_MUTEXES */
46