#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 unsigned long wait_for_completion_interruptible_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