1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __LINUX_COMPLETION_H
3 #define __LINUX_COMPLETION_H
6 * (C) Copyright 2001 Linus Torvalds
8 * Atomic wait-for-completion handler data structures.
9 * See kernel/sched/completion.c for details.
12 #include <linux/wait.h>
13 #ifdef CONFIG_LOCKDEP_COMPLETIONS
14 #include <linux/lockdep.h>
18 * struct completion - structure used to maintain state for a "completion"
20 * This is the opaque structure used to maintain the state for a "completion".
21 * Completions currently use a FIFO to queue threads that have to wait for
22 * the "completion" event.
24 * See also: complete(), wait_for_completion() (and friends _timeout,
25 * _interruptible, _interruptible_timeout, and _killable), init_completion(),
26 * reinit_completion(), and macros DECLARE_COMPLETION(),
27 * DECLARE_COMPLETION_ONSTACK().
31 wait_queue_head_t wait;
32 #ifdef CONFIG_LOCKDEP_COMPLETIONS
33 struct lockdep_map_cross map;
37 #ifdef CONFIG_LOCKDEP_COMPLETIONS
38 static inline void complete_acquire(struct completion *x)
40 lock_acquire_exclusive((struct lockdep_map *)&x->map, 0, 0, NULL, _RET_IP_);
43 static inline void complete_release(struct completion *x)
45 lock_release((struct lockdep_map *)&x->map, 0, _RET_IP_);
48 static inline void complete_release_commit(struct completion *x)
50 lock_commit_crosslock((struct lockdep_map *)&x->map);
53 #define init_completion_map(x, m) \
55 lockdep_init_map_crosslock((struct lockdep_map *)&(x)->map, \
56 (m)->name, (m)->key, 0); \
57 __init_completion(x); \
60 #define init_completion(x) \
62 static struct lock_class_key __key; \
63 lockdep_init_map_crosslock((struct lockdep_map *)&(x)->map, \
66 __init_completion(x); \
69 #define init_completion_map(x, m) __init_completion(x)
70 #define init_completion(x) __init_completion(x)
71 static inline void complete_acquire(struct completion *x) {}
72 static inline void complete_release(struct completion *x) {}
73 static inline void complete_release_commit(struct completion *x) {}
76 #ifdef CONFIG_LOCKDEP_COMPLETIONS
77 #define COMPLETION_INITIALIZER(work) \
78 { 0, __WAIT_QUEUE_HEAD_INITIALIZER((work).wait), \
79 STATIC_CROSS_LOCKDEP_MAP_INIT("(completion)" #work, &(work)) }
81 #define COMPLETION_INITIALIZER(work) \
82 { 0, __WAIT_QUEUE_HEAD_INITIALIZER((work).wait) }
85 #define COMPLETION_INITIALIZER_ONSTACK_MAP(work, map) \
86 (*({ init_completion_map(&(work), &(map)); &(work); }))
88 #define COMPLETION_INITIALIZER_ONSTACK(work) \
89 (*({ init_completion(&work); &work; }))
92 * DECLARE_COMPLETION - declare and initialize a completion structure
93 * @work: identifier for the completion structure
95 * This macro declares and initializes a completion structure. Generally used
96 * for static declarations. You should use the _ONSTACK variant for automatic
99 #define DECLARE_COMPLETION(work) \
100 struct completion work = COMPLETION_INITIALIZER(work)
103 * Lockdep needs to run a non-constant initializer for on-stack
104 * completions - so we use the _ONSTACK() variant for those that
105 * are on the kernel stack:
108 * DECLARE_COMPLETION_ONSTACK - declare and initialize a completion structure
109 * @work: identifier for the completion structure
111 * This macro declares and initializes a completion structure on the kernel
114 #ifdef CONFIG_LOCKDEP
115 # define DECLARE_COMPLETION_ONSTACK(work) \
116 struct completion work = COMPLETION_INITIALIZER_ONSTACK(work)
117 # define DECLARE_COMPLETION_ONSTACK_MAP(work, map) \
118 struct completion work = COMPLETION_INITIALIZER_ONSTACK_MAP(work, map)
120 # define DECLARE_COMPLETION_ONSTACK(work) DECLARE_COMPLETION(work)
121 # define DECLARE_COMPLETION_ONSTACK_MAP(work, map) DECLARE_COMPLETION(work)
125 * init_completion - Initialize a dynamically allocated completion
126 * @x: pointer to completion structure that is to be initialized
128 * This inline function will initialize a dynamically created completion
131 static inline void __init_completion(struct completion *x)
134 init_waitqueue_head(&x->wait);
138 * reinit_completion - reinitialize a completion structure
139 * @x: pointer to completion structure that is to be reinitialized
141 * This inline function should be used to reinitialize a completion structure so it can
142 * be reused. This is especially important after complete_all() is used.
144 static inline void reinit_completion(struct completion *x)
149 extern void wait_for_completion(struct completion *);
150 extern void wait_for_completion_io(struct completion *);
151 extern int wait_for_completion_interruptible(struct completion *x);
152 extern int wait_for_completion_killable(struct completion *x);
153 extern unsigned long wait_for_completion_timeout(struct completion *x,
154 unsigned long timeout);
155 extern unsigned long wait_for_completion_io_timeout(struct completion *x,
156 unsigned long timeout);
157 extern long wait_for_completion_interruptible_timeout(
158 struct completion *x, unsigned long timeout);
159 extern long wait_for_completion_killable_timeout(
160 struct completion *x, unsigned long timeout);
161 extern bool try_wait_for_completion(struct completion *x);
162 extern bool completion_done(struct completion *x);
164 extern void complete(struct completion *);
165 extern void complete_all(struct completion *);