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marcus.erl |
#ifndef _LINUX_WAIT_H
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#define _LINUX_WAIT_H
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#define WNOHANG 0x00000001
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#define WUNTRACED 0x00000002
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#define WSTOPPED WUNTRACED
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#define WEXITED 0x00000004
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#define WCONTINUED 0x00000008
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#define WNOWAIT 0x01000000 /* Don't reap, just poll status. */
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#define __WNOTHREAD 0x20000000 /* Don't wait on children of other threads in this group */
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#define __WALL 0x40000000 /* Wait on all children, regardless of type */
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#define __WCLONE 0x80000000 /* Wait only on non-SIGCHLD children */
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/* First argument to waitid: */
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#define P_ALL 0
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#define P_PID 1
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#define P_PGID 2
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#ifdef __KERNEL__
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#include <linux/list.h>
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#include <linux/stddef.h>
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#include <linux/spinlock.h>
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#include <asm/system.h>
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#include <asm/current.h>
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typedef struct __wait_queue wait_queue_t;
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typedef int (*wait_queue_func_t)(wait_queue_t *wait, unsigned mode, int sync, void *key);
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int default_wake_function(wait_queue_t *wait, unsigned mode, int sync, void *key);
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struct __wait_queue {
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unsigned int flags;
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#define WQ_FLAG_EXCLUSIVE 0x01
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void *private;
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wait_queue_func_t func;
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struct list_head task_list;
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};
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struct wait_bit_key {
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void *flags;
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int bit_nr;
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};
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struct wait_bit_queue {
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struct wait_bit_key key;
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wait_queue_t wait;
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};
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struct __wait_queue_head {
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spinlock_t lock;
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struct list_head task_list;
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};
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typedef struct __wait_queue_head wait_queue_head_t;
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struct task_struct;
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/*
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* Macros for declaration and initialisaton of the datatypes
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*/
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#define __WAITQUEUE_INITIALIZER(name, tsk) { \
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.private = tsk, \
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.func = default_wake_function, \
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.task_list = { NULL, NULL } }
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#define DECLARE_WAITQUEUE(name, tsk) \
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wait_queue_t name = __WAITQUEUE_INITIALIZER(name, tsk)
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#define __WAIT_QUEUE_HEAD_INITIALIZER(name) { \
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.lock = __SPIN_LOCK_UNLOCKED(name.lock), \
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.task_list = { &(name).task_list, &(name).task_list } }
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#define DECLARE_WAIT_QUEUE_HEAD(name) \
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wait_queue_head_t name = __WAIT_QUEUE_HEAD_INITIALIZER(name)
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#define __WAIT_BIT_KEY_INITIALIZER(word, bit) \
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{ .flags = word, .bit_nr = bit, }
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| 80 |
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extern void init_waitqueue_head(wait_queue_head_t *q);
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#ifdef CONFIG_LOCKDEP
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# define __WAIT_QUEUE_HEAD_INIT_ONSTACK(name) \
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({ init_waitqueue_head(&name); name; })
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# define DECLARE_WAIT_QUEUE_HEAD_ONSTACK(name) \
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wait_queue_head_t name = __WAIT_QUEUE_HEAD_INIT_ONSTACK(name)
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#else
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# define DECLARE_WAIT_QUEUE_HEAD_ONSTACK(name) DECLARE_WAIT_QUEUE_HEAD(name)
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#endif
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static inline void init_waitqueue_entry(wait_queue_t *q, struct task_struct *p)
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{
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q->flags = 0;
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q->private = p;
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q->func = default_wake_function;
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}
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static inline void init_waitqueue_func_entry(wait_queue_t *q,
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wait_queue_func_t func)
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{
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q->flags = 0;
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q->private = NULL;
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q->func = func;
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}
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static inline int waitqueue_active(wait_queue_head_t *q)
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{
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return !list_empty(&q->task_list);
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}
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/*
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* Used to distinguish between sync and async io wait context:
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* sync i/o typically specifies a NULL wait queue entry or a wait
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* queue entry bound to a task (current task) to wake up.
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* aio specifies a wait queue entry with an async notification
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* callback routine, not associated with any task.
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*/
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#define is_sync_wait(wait) (!(wait) || ((wait)->private))
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extern void FASTCALL(add_wait_queue(wait_queue_head_t *q, wait_queue_t * wait));
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extern void FASTCALL(add_wait_queue_exclusive(wait_queue_head_t *q, wait_queue_t * wait));
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extern void FASTCALL(remove_wait_queue(wait_queue_head_t *q, wait_queue_t * wait));
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static inline void __add_wait_queue(wait_queue_head_t *head, wait_queue_t *new)
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{
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list_add(&new->task_list, &head->task_list);
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}
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| 129 |
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/*
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* Used for wake-one threads:
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*/
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static inline void __add_wait_queue_tail(wait_queue_head_t *head,
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wait_queue_t *new)
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{
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list_add_tail(&new->task_list, &head->task_list);
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}
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static inline void __remove_wait_queue(wait_queue_head_t *head,
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wait_queue_t *old)
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{
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list_del(&old->task_list);
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}
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| 144 |
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void FASTCALL(__wake_up(wait_queue_head_t *q, unsigned int mode, int nr, void *key));
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extern void FASTCALL(__wake_up_locked(wait_queue_head_t *q, unsigned int mode));
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extern void FASTCALL(__wake_up_sync(wait_queue_head_t *q, unsigned int mode, int nr));
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void FASTCALL(__wake_up_bit(wait_queue_head_t *, void *, int));
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int FASTCALL(__wait_on_bit(wait_queue_head_t *, struct wait_bit_queue *, int (*)(void *), unsigned));
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int FASTCALL(__wait_on_bit_lock(wait_queue_head_t *, struct wait_bit_queue *, int (*)(void *), unsigned));
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void FASTCALL(wake_up_bit(void *, int));
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int FASTCALL(out_of_line_wait_on_bit(void *, int, int (*)(void *), unsigned));
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int FASTCALL(out_of_line_wait_on_bit_lock(void *, int, int (*)(void *), unsigned));
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wait_queue_head_t *FASTCALL(bit_waitqueue(void *, int));
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#define wake_up(x) __wake_up(x, TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE, 1, NULL)
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#define wake_up_nr(x, nr) __wake_up(x, TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE, nr, NULL)
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#define wake_up_all(x) __wake_up(x, TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE, 0, NULL)
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#define wake_up_interruptible(x) __wake_up(x, TASK_INTERRUPTIBLE, 1, NULL)
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#define wake_up_interruptible_nr(x, nr) __wake_up(x, TASK_INTERRUPTIBLE, nr, NULL)
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#define wake_up_interruptible_all(x) __wake_up(x, TASK_INTERRUPTIBLE, 0, NULL)
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#define wake_up_locked(x) __wake_up_locked((x), TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE)
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#define wake_up_interruptible_sync(x) __wake_up_sync((x),TASK_INTERRUPTIBLE, 1)
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#define __wait_event(wq, condition) \
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do { \
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DEFINE_WAIT(__wait); \
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\
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| 168 |
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for (;;) { \
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| 169 |
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prepare_to_wait(&wq, &__wait, TASK_UNINTERRUPTIBLE); \
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| 170 |
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if (condition) \
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| 171 |
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break; \
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| 172 |
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schedule(); \
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| 173 |
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} \
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| 174 |
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finish_wait(&wq, &__wait); \
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| 175 |
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} while (0)
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| 176 |
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| 177 |
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/**
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| 178 |
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* wait_event - sleep until a condition gets true
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| 179 |
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* @wq: the waitqueue to wait on
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| 180 |
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* @condition: a C expression for the event to wait for
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| 181 |
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*
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| 182 |
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* The process is put to sleep (TASK_UNINTERRUPTIBLE) until the
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| 183 |
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* @condition evaluates to true. The @condition is checked each time
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| 184 |
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* the waitqueue @wq is woken up.
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| 185 |
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*
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| 186 |
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* wake_up() has to be called after changing any variable that could
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| 187 |
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* change the result of the wait condition.
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| 188 |
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*/
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| 189 |
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#define wait_event(wq, condition) \
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| 190 |
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do { \
|
| 191 |
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if (condition) \
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| 192 |
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break; \
|
| 193 |
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__wait_event(wq, condition); \
|
| 194 |
|
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} while (0)
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| 195 |
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| 196 |
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#define __wait_event_timeout(wq, condition, ret) \
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| 197 |
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do { \
|
| 198 |
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DEFINE_WAIT(__wait); \
|
| 199 |
|
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\
|
| 200 |
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for (;;) { \
|
| 201 |
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prepare_to_wait(&wq, &__wait, TASK_UNINTERRUPTIBLE); \
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| 202 |
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if (condition) \
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| 203 |
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break; \
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| 204 |
|
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ret = schedule_timeout(ret); \
|
| 205 |
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if (!ret) \
|
| 206 |
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break; \
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| 207 |
|
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} \
|
| 208 |
|
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finish_wait(&wq, &__wait); \
|
| 209 |
|
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} while (0)
|
| 210 |
|
|
|
| 211 |
|
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/**
|
| 212 |
|
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* wait_event_timeout - sleep until a condition gets true or a timeout elapses
|
| 213 |
|
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* @wq: the waitqueue to wait on
|
| 214 |
|
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* @condition: a C expression for the event to wait for
|
| 215 |
|
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* @timeout: timeout, in jiffies
|
| 216 |
|
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*
|
| 217 |
|
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* The process is put to sleep (TASK_UNINTERRUPTIBLE) until the
|
| 218 |
|
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* @condition evaluates to true. The @condition is checked each time
|
| 219 |
|
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* the waitqueue @wq is woken up.
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| 220 |
|
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*
|
| 221 |
|
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* wake_up() has to be called after changing any variable that could
|
| 222 |
|
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* change the result of the wait condition.
|
| 223 |
|
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*
|
| 224 |
|
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* The function returns 0 if the @timeout elapsed, and the remaining
|
| 225 |
|
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* jiffies if the condition evaluated to true before the timeout elapsed.
|
| 226 |
|
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*/
|
| 227 |
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#define wait_event_timeout(wq, condition, timeout) \
|
| 228 |
|
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({ \
|
| 229 |
|
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long __ret = timeout; \
|
| 230 |
|
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if (!(condition)) \
|
| 231 |
|
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__wait_event_timeout(wq, condition, __ret); \
|
| 232 |
|
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__ret; \
|
| 233 |
|
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})
|
| 234 |
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|
| 235 |
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#define __wait_event_interruptible(wq, condition, ret) \
|
| 236 |
|
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do { \
|
| 237 |
|
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DEFINE_WAIT(__wait); \
|
| 238 |
|
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\
|
| 239 |
|
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for (;;) { \
|
| 240 |
|
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prepare_to_wait(&wq, &__wait, TASK_INTERRUPTIBLE); \
|
| 241 |
|
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if (condition) \
|
| 242 |
|
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break; \
|
| 243 |
|
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if (!signal_pending(current)) { \
|
| 244 |
|
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schedule(); \
|
| 245 |
|
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continue; \
|
| 246 |
|
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} \
|
| 247 |
|
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ret = -ERESTARTSYS; \
|
| 248 |
|
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break; \
|
| 249 |
|
|
} \
|
| 250 |
|
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finish_wait(&wq, &__wait); \
|
| 251 |
|
|
} while (0)
|
| 252 |
|
|
|
| 253 |
|
|
/**
|
| 254 |
|
|
* wait_event_interruptible - sleep until a condition gets true
|
| 255 |
|
|
* @wq: the waitqueue to wait on
|
| 256 |
|
|
* @condition: a C expression for the event to wait for
|
| 257 |
|
|
*
|
| 258 |
|
|
* The process is put to sleep (TASK_INTERRUPTIBLE) until the
|
| 259 |
|
|
* @condition evaluates to true or a signal is received.
|
| 260 |
|
|
* The @condition is checked each time the waitqueue @wq is woken up.
|
| 261 |
|
|
*
|
| 262 |
|
|
* wake_up() has to be called after changing any variable that could
|
| 263 |
|
|
* change the result of the wait condition.
|
| 264 |
|
|
*
|
| 265 |
|
|
* The function will return -ERESTARTSYS if it was interrupted by a
|
| 266 |
|
|
* signal and 0 if @condition evaluated to true.
|
| 267 |
|
|
*/
|
| 268 |
|
|
#define wait_event_interruptible(wq, condition) \
|
| 269 |
|
|
({ \
|
| 270 |
|
|
int __ret = 0; \
|
| 271 |
|
|
if (!(condition)) \
|
| 272 |
|
|
__wait_event_interruptible(wq, condition, __ret); \
|
| 273 |
|
|
__ret; \
|
| 274 |
|
|
})
|
| 275 |
|
|
|
| 276 |
|
|
#define __wait_event_interruptible_timeout(wq, condition, ret) \
|
| 277 |
|
|
do { \
|
| 278 |
|
|
DEFINE_WAIT(__wait); \
|
| 279 |
|
|
\
|
| 280 |
|
|
for (;;) { \
|
| 281 |
|
|
prepare_to_wait(&wq, &__wait, TASK_INTERRUPTIBLE); \
|
| 282 |
|
|
if (condition) \
|
| 283 |
|
|
break; \
|
| 284 |
|
|
if (!signal_pending(current)) { \
|
| 285 |
|
|
ret = schedule_timeout(ret); \
|
| 286 |
|
|
if (!ret) \
|
| 287 |
|
|
break; \
|
| 288 |
|
|
continue; \
|
| 289 |
|
|
} \
|
| 290 |
|
|
ret = -ERESTARTSYS; \
|
| 291 |
|
|
break; \
|
| 292 |
|
|
} \
|
| 293 |
|
|
finish_wait(&wq, &__wait); \
|
| 294 |
|
|
} while (0)
|
| 295 |
|
|
|
| 296 |
|
|
/**
|
| 297 |
|
|
* wait_event_interruptible_timeout - sleep until a condition gets true or a timeout elapses
|
| 298 |
|
|
* @wq: the waitqueue to wait on
|
| 299 |
|
|
* @condition: a C expression for the event to wait for
|
| 300 |
|
|
* @timeout: timeout, in jiffies
|
| 301 |
|
|
*
|
| 302 |
|
|
* The process is put to sleep (TASK_INTERRUPTIBLE) until the
|
| 303 |
|
|
* @condition evaluates to true or a signal is received.
|
| 304 |
|
|
* The @condition is checked each time the waitqueue @wq is woken up.
|
| 305 |
|
|
*
|
| 306 |
|
|
* wake_up() has to be called after changing any variable that could
|
| 307 |
|
|
* change the result of the wait condition.
|
| 308 |
|
|
*
|
| 309 |
|
|
* The function returns 0 if the @timeout elapsed, -ERESTARTSYS if it
|
| 310 |
|
|
* was interrupted by a signal, and the remaining jiffies otherwise
|
| 311 |
|
|
* if the condition evaluated to true before the timeout elapsed.
|
| 312 |
|
|
*/
|
| 313 |
|
|
#define wait_event_interruptible_timeout(wq, condition, timeout) \
|
| 314 |
|
|
({ \
|
| 315 |
|
|
long __ret = timeout; \
|
| 316 |
|
|
if (!(condition)) \
|
| 317 |
|
|
__wait_event_interruptible_timeout(wq, condition, __ret); \
|
| 318 |
|
|
__ret; \
|
| 319 |
|
|
})
|
| 320 |
|
|
|
| 321 |
|
|
#define __wait_event_interruptible_exclusive(wq, condition, ret) \
|
| 322 |
|
|
do { \
|
| 323 |
|
|
DEFINE_WAIT(__wait); \
|
| 324 |
|
|
\
|
| 325 |
|
|
for (;;) { \
|
| 326 |
|
|
prepare_to_wait_exclusive(&wq, &__wait, \
|
| 327 |
|
|
TASK_INTERRUPTIBLE); \
|
| 328 |
|
|
if (condition) \
|
| 329 |
|
|
break; \
|
| 330 |
|
|
if (!signal_pending(current)) { \
|
| 331 |
|
|
schedule(); \
|
| 332 |
|
|
continue; \
|
| 333 |
|
|
} \
|
| 334 |
|
|
ret = -ERESTARTSYS; \
|
| 335 |
|
|
break; \
|
| 336 |
|
|
} \
|
| 337 |
|
|
finish_wait(&wq, &__wait); \
|
| 338 |
|
|
} while (0)
|
| 339 |
|
|
|
| 340 |
|
|
#define wait_event_interruptible_exclusive(wq, condition) \
|
| 341 |
|
|
({ \
|
| 342 |
|
|
int __ret = 0; \
|
| 343 |
|
|
if (!(condition)) \
|
| 344 |
|
|
__wait_event_interruptible_exclusive(wq, condition, __ret);\
|
| 345 |
|
|
__ret; \
|
| 346 |
|
|
})
|
| 347 |
|
|
|
| 348 |
|
|
/*
|
| 349 |
|
|
* Must be called with the spinlock in the wait_queue_head_t held.
|
| 350 |
|
|
*/
|
| 351 |
|
|
static inline void add_wait_queue_exclusive_locked(wait_queue_head_t *q,
|
| 352 |
|
|
wait_queue_t * wait)
|
| 353 |
|
|
{
|
| 354 |
|
|
wait->flags |= WQ_FLAG_EXCLUSIVE;
|
| 355 |
|
|
__add_wait_queue_tail(q, wait);
|
| 356 |
|
|
}
|
| 357 |
|
|
|
| 358 |
|
|
/*
|
| 359 |
|
|
* Must be called with the spinlock in the wait_queue_head_t held.
|
| 360 |
|
|
*/
|
| 361 |
|
|
static inline void remove_wait_queue_locked(wait_queue_head_t *q,
|
| 362 |
|
|
wait_queue_t * wait)
|
| 363 |
|
|
{
|
| 364 |
|
|
__remove_wait_queue(q, wait);
|
| 365 |
|
|
}
|
| 366 |
|
|
|
| 367 |
|
|
/*
|
| 368 |
|
|
* These are the old interfaces to sleep waiting for an event.
|
| 369 |
|
|
* They are racy. DO NOT use them, use the wait_event* interfaces above.
|
| 370 |
|
|
* We plan to remove these interfaces.
|
| 371 |
|
|
*/
|
| 372 |
|
|
extern void sleep_on(wait_queue_head_t *q);
|
| 373 |
|
|
extern long sleep_on_timeout(wait_queue_head_t *q,
|
| 374 |
|
|
signed long timeout);
|
| 375 |
|
|
extern void interruptible_sleep_on(wait_queue_head_t *q);
|
| 376 |
|
|
extern long interruptible_sleep_on_timeout(wait_queue_head_t *q,
|
| 377 |
|
|
signed long timeout);
|
| 378 |
|
|
|
| 379 |
|
|
/*
|
| 380 |
|
|
* Waitqueues which are removed from the waitqueue_head at wakeup time
|
| 381 |
|
|
*/
|
| 382 |
|
|
void FASTCALL(prepare_to_wait(wait_queue_head_t *q,
|
| 383 |
|
|
wait_queue_t *wait, int state));
|
| 384 |
|
|
void FASTCALL(prepare_to_wait_exclusive(wait_queue_head_t *q,
|
| 385 |
|
|
wait_queue_t *wait, int state));
|
| 386 |
|
|
void FASTCALL(finish_wait(wait_queue_head_t *q, wait_queue_t *wait));
|
| 387 |
|
|
int autoremove_wake_function(wait_queue_t *wait, unsigned mode, int sync, void *key);
|
| 388 |
|
|
int wake_bit_function(wait_queue_t *wait, unsigned mode, int sync, void *key);
|
| 389 |
|
|
|
| 390 |
|
|
#define DEFINE_WAIT(name) \
|
| 391 |
|
|
wait_queue_t name = { \
|
| 392 |
|
|
.private = current, \
|
| 393 |
|
|
.func = autoremove_wake_function, \
|
| 394 |
|
|
.task_list = LIST_HEAD_INIT((name).task_list), \
|
| 395 |
|
|
}
|
| 396 |
|
|
|
| 397 |
|
|
#define DEFINE_WAIT_BIT(name, word, bit) \
|
| 398 |
|
|
struct wait_bit_queue name = { \
|
| 399 |
|
|
.key = __WAIT_BIT_KEY_INITIALIZER(word, bit), \
|
| 400 |
|
|
.wait = { \
|
| 401 |
|
|
.private = current, \
|
| 402 |
|
|
.func = wake_bit_function, \
|
| 403 |
|
|
.task_list = \
|
| 404 |
|
|
LIST_HEAD_INIT((name).wait.task_list), \
|
| 405 |
|
|
}, \
|
| 406 |
|
|
}
|
| 407 |
|
|
|
| 408 |
|
|
#define init_wait(wait) \
|
| 409 |
|
|
do { \
|
| 410 |
|
|
(wait)->private = current; \
|
| 411 |
|
|
(wait)->func = autoremove_wake_function; \
|
| 412 |
|
|
INIT_LIST_HEAD(&(wait)->task_list); \
|
| 413 |
|
|
} while (0)
|
| 414 |
|
|
|
| 415 |
|
|
/**
|
| 416 |
|
|
* wait_on_bit - wait for a bit to be cleared
|
| 417 |
|
|
* @word: the word being waited on, a kernel virtual address
|
| 418 |
|
|
* @bit: the bit of the word being waited on
|
| 419 |
|
|
* @action: the function used to sleep, which may take special actions
|
| 420 |
|
|
* @mode: the task state to sleep in
|
| 421 |
|
|
*
|
| 422 |
|
|
* There is a standard hashed waitqueue table for generic use. This
|
| 423 |
|
|
* is the part of the hashtable's accessor API that waits on a bit.
|
| 424 |
|
|
* For instance, if one were to have waiters on a bitflag, one would
|
| 425 |
|
|
* call wait_on_bit() in threads waiting for the bit to clear.
|
| 426 |
|
|
* One uses wait_on_bit() where one is waiting for the bit to clear,
|
| 427 |
|
|
* but has no intention of setting it.
|
| 428 |
|
|
*/
|
| 429 |
|
|
static inline int wait_on_bit(void *word, int bit,
|
| 430 |
|
|
int (*action)(void *), unsigned mode)
|
| 431 |
|
|
{
|
| 432 |
|
|
if (!test_bit(bit, word))
|
| 433 |
|
|
return 0;
|
| 434 |
|
|
return out_of_line_wait_on_bit(word, bit, action, mode);
|
| 435 |
|
|
}
|
| 436 |
|
|
|
| 437 |
|
|
/**
|
| 438 |
|
|
* wait_on_bit_lock - wait for a bit to be cleared, when wanting to set it
|
| 439 |
|
|
* @word: the word being waited on, a kernel virtual address
|
| 440 |
|
|
* @bit: the bit of the word being waited on
|
| 441 |
|
|
* @action: the function used to sleep, which may take special actions
|
| 442 |
|
|
* @mode: the task state to sleep in
|
| 443 |
|
|
*
|
| 444 |
|
|
* There is a standard hashed waitqueue table for generic use. This
|
| 445 |
|
|
* is the part of the hashtable's accessor API that waits on a bit
|
| 446 |
|
|
* when one intends to set it, for instance, trying to lock bitflags.
|
| 447 |
|
|
* For instance, if one were to have waiters trying to set bitflag
|
| 448 |
|
|
* and waiting for it to clear before setting it, one would call
|
| 449 |
|
|
* wait_on_bit() in threads waiting to be able to set the bit.
|
| 450 |
|
|
* One uses wait_on_bit_lock() where one is waiting for the bit to
|
| 451 |
|
|
* clear with the intention of setting it, and when done, clearing it.
|
| 452 |
|
|
*/
|
| 453 |
|
|
static inline int wait_on_bit_lock(void *word, int bit,
|
| 454 |
|
|
int (*action)(void *), unsigned mode)
|
| 455 |
|
|
{
|
| 456 |
|
|
if (!test_and_set_bit(bit, word))
|
| 457 |
|
|
return 0;
|
| 458 |
|
|
return out_of_line_wait_on_bit_lock(word, bit, action, mode);
|
| 459 |
|
|
}
|
| 460 |
|
|
|
| 461 |
|
|
#endif /* __KERNEL__ */
|
| 462 |
|
|
|
| 463 |
|
|
#endif
|
