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Diffstat (limited to 'include/linux/completion.h')
-rw-r--r-- | include/linux/completion.h | 104 |
1 files changed, 104 insertions, 0 deletions
diff --git a/include/linux/completion.h b/include/linux/completion.h new file mode 100644 index 00000000..51494e6b --- /dev/null +++ b/include/linux/completion.h @@ -0,0 +1,104 @@ +#ifndef __LINUX_COMPLETION_H +#define __LINUX_COMPLETION_H + +/* + * (C) Copyright 2001 Linus Torvalds + * + * Atomic wait-for-completion handler data structures. + * See kernel/sched.c for details. + */ + +#include <linux/wait.h> + +/* + * struct completion - structure used to maintain state for a "completion" + * + * This is the opaque structure used to maintain the state for a "completion". + * Completions currently use a FIFO to queue threads that have to wait for + * the "completion" event. + * + * See also: complete(), wait_for_completion() (and friends _timeout, + * _interruptible, _interruptible_timeout, and _killable), init_completion(), + * and macros DECLARE_COMPLETION(), DECLARE_COMPLETION_ONSTACK(), and + * INIT_COMPLETION(). + */ +struct completion { + unsigned int done; + wait_queue_head_t wait; +}; + +#define COMPLETION_INITIALIZER(work) \ + { 0, __WAIT_QUEUE_HEAD_INITIALIZER((work).wait) } + +#define COMPLETION_INITIALIZER_ONSTACK(work) \ + ({ init_completion(&work); work; }) + +/** + * DECLARE_COMPLETION - declare and initialize a completion structure + * @work: identifier for the completion structure + * + * This macro declares and initializes a completion structure. Generally used + * for static declarations. You should use the _ONSTACK variant for automatic + * variables. + */ +#define DECLARE_COMPLETION(work) \ + struct completion work = COMPLETION_INITIALIZER(work) + +/* + * Lockdep needs to run a non-constant initializer for on-stack + * completions - so we use the _ONSTACK() variant for those that + * are on the kernel stack: + */ +/** + * DECLARE_COMPLETION_ONSTACK - declare and initialize a completion structure + * @work: identifier for the completion structure + * + * This macro declares and initializes a completion structure on the kernel + * stack. + */ +#ifdef CONFIG_LOCKDEP +# define DECLARE_COMPLETION_ONSTACK(work) \ + struct completion work = COMPLETION_INITIALIZER_ONSTACK(work) +#else +# define DECLARE_COMPLETION_ONSTACK(work) DECLARE_COMPLETION(work) +#endif + +/** + * init_completion - Initialize a dynamically allocated completion + * @x: completion structure that is to be initialized + * + * This inline function will initialize a dynamically created completion + * structure. + */ +static inline void init_completion(struct completion *x) +{ + x->done = 0; + init_waitqueue_head(&x->wait); +} + +extern void wait_for_completion(struct completion *); +extern int wait_for_completion_interruptible(struct completion *x); +extern int wait_for_completion_killable(struct completion *x); +extern unsigned long wait_for_completion_timeout(struct completion *x, + unsigned long timeout); +extern long wait_for_completion_interruptible_timeout( + struct completion *x, unsigned long timeout); +extern long wait_for_completion_killable_timeout( + struct completion *x, unsigned long timeout); +extern bool try_wait_for_completion(struct completion *x); +extern bool completion_done(struct completion *x); + +extern void complete(struct completion *); +extern void complete_all(struct completion *); + +/** + * INIT_COMPLETION - reinitialize a completion structure + * @x: completion structure to be reinitialized + * + * This macro should be used to reinitialize a completion structure so it can + * be reused. This is especially important after complete_all() is used. + */ +#define INIT_COMPLETION(x) ((x).done = 0) + + +#endif |