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#ifndef _LINUX_WAIT_H
#define _LINUX_WAIT_H
#define WNOHANG 0x00000001
#define WUNTRACED 0x00000002
#define __WNOTHREAD 0x20000000 /* Don't wait on children of other threads in this group */
#define __WALL 0x40000000 /* Wait on all children, regardless of type */
#define __WCLONE 0x80000000 /* Wait only on non-SIGCHLD children */
#ifdef __KERNEL__
#include <linux/config.h>
#include <linux/list.h>
#include <linux/stddef.h>
#include <linux/spinlock.h>
#include <asm/system.h>
typedef struct __wait_queue wait_queue_t;
typedef int (*wait_queue_func_t)(wait_queue_t *wait, unsigned mode, int sync, void *key);
int default_wake_function(wait_queue_t *wait, unsigned mode, int sync, void *key);
struct __wait_queue {
unsigned int flags;
#define WQ_FLAG_EXCLUSIVE 0x01
struct task_struct * task;
wait_queue_func_t func;
struct list_head task_list;
};
struct __wait_queue_head {
spinlock_t lock;
struct list_head task_list;
};
typedef struct __wait_queue_head wait_queue_head_t;
/*
* Macros for declaration and initialisaton of the datatypes
*/
#define __WAITQUEUE_INITIALIZER(name, tsk) { \
.task = tsk, \
.func = default_wake_function, \
.task_list = { NULL, NULL } }
#define DECLARE_WAITQUEUE(name, tsk) \
wait_queue_t name = __WAITQUEUE_INITIALIZER(name, tsk)
#define __WAIT_QUEUE_HEAD_INITIALIZER(name) { \
.lock = SPIN_LOCK_UNLOCKED, \
.task_list = { &(name).task_list, &(name).task_list } }
#define DECLARE_WAIT_QUEUE_HEAD(name) \
wait_queue_head_t name = __WAIT_QUEUE_HEAD_INITIALIZER(name)
static inline void init_waitqueue_head(wait_queue_head_t *q)
{
q->lock = SPIN_LOCK_UNLOCKED;
INIT_LIST_HEAD(&q->task_list);
}
static inline void init_waitqueue_entry(wait_queue_t *q, struct task_struct *p)
{
q->flags = 0;
q->task = p;
q->func = default_wake_function;
}
static inline void init_waitqueue_func_entry(wait_queue_t *q,
wait_queue_func_t func)
{
q->flags = 0;
q->task = NULL;
q->func = func;
}
static inline int waitqueue_active(wait_queue_head_t *q)
{
return !list_empty(&q->task_list);
}
extern void FASTCALL(add_wait_queue(wait_queue_head_t *q, wait_queue_t * wait));
extern void FASTCALL(add_wait_queue_exclusive(wait_queue_head_t *q, wait_queue_t * wait));
extern void FASTCALL(remove_wait_queue(wait_queue_head_t *q, wait_queue_t * wait));
static inline void __add_wait_queue(wait_queue_head_t *head, wait_queue_t *new)
{
list_add(&new->task_list, &head->task_list);
}
/*
* Used for wake-one threads:
*/
static inline void __add_wait_queue_tail(wait_queue_head_t *head,
wait_queue_t *new)
{
list_add_tail(&new->task_list, &head->task_list);
}
static inline void __remove_wait_queue(wait_queue_head_t *head,
wait_queue_t *old)
{
list_del(&old->task_list);
}
void FASTCALL(__wake_up(wait_queue_head_t *q, unsigned int mode, int nr, void *key));
extern void FASTCALL(__wake_up_locked(wait_queue_head_t *q, unsigned int mode));
extern void FASTCALL(__wake_up_sync(wait_queue_head_t *q, unsigned int mode, int nr));
#define wake_up(x) __wake_up(x, TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE, 1, NULL)
#define wake_up_nr(x, nr) __wake_up(x, TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE, nr, NULL)
#define wake_up_all(x) __wake_up(x, TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE, 0, NULL)
#define wake_up_all_sync(x) __wake_up_sync((x),TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE, 0)
#define wake_up_interruptible(x) __wake_up(x, TASK_INTERRUPTIBLE, 1, NULL)
#define wake_up_interruptible_nr(x, nr) __wake_up(x, TASK_INTERRUPTIBLE, nr, NULL)
#define wake_up_interruptible_all(x) __wake_up(x, TASK_INTERRUPTIBLE, 0, NULL)
#define wake_up_locked(x) __wake_up_locked((x), TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE)
#define wake_up_interruptible_sync(x) __wake_up_sync((x),TASK_INTERRUPTIBLE, 1)
#define __wait_event(wq, condition) \
do { \
wait_queue_t __wait; \
init_waitqueue_entry(&__wait, current); \
\
add_wait_queue(&wq, &__wait); \
for (;;) { \
set_current_state(TASK_UNINTERRUPTIBLE); \
if (condition) \
break; \
schedule(); \
} \
current->state = TASK_RUNNING; \
remove_wait_queue(&wq, &__wait); \
} while (0)
#define wait_event(wq, condition) \
do { \
if (condition) \
break; \
__wait_event(wq, condition); \
} while (0)
#define __wait_event_interruptible(wq, condition, ret) \
do { \
wait_queue_t __wait; \
init_waitqueue_entry(&__wait, current); \
\
add_wait_queue(&wq, &__wait); \
for (;;) { \
set_current_state(TASK_INTERRUPTIBLE); \
if (condition) \
break; \
if (!signal_pending(current)) { \
schedule(); \
continue; \
} \
ret = -ERESTARTSYS; \
break; \
} \
current->state = TASK_RUNNING; \
remove_wait_queue(&wq, &__wait); \
} while (0)
#define wait_event_interruptible(wq, condition) \
({ \
int __ret = 0; \
if (!(condition)) \
__wait_event_interruptible(wq, condition, __ret); \
__ret; \
})
#define __wait_event_interruptible_timeout(wq, condition, ret) \
do { \
wait_queue_t __wait; \
init_waitqueue_entry(&__wait, current); \
\
add_wait_queue(&wq, &__wait); \
for (;;) { \
set_current_state(TASK_INTERRUPTIBLE); \
if (condition) \
break; \
if (!signal_pending(current)) { \
ret = schedule_timeout(ret); \
if (!ret) \
break; \
continue; \
} \
ret = -ERESTARTSYS; \
break; \
} \
current->state = TASK_RUNNING; \
remove_wait_queue(&wq, &__wait); \
} while (0)
#define wait_event_interruptible_timeout(wq, condition, timeout) \
({ \
long __ret = timeout; \
if (!(condition)) \
__wait_event_interruptible_timeout(wq, condition, __ret); \
__ret; \
})
#define __wait_event_interruptible_exclusive(wq, condition, ret) \
do { \
wait_queue_t __wait; \
init_waitqueue_entry(&__wait, current); \
\
add_wait_queue_exclusive(&wq, &__wait); \
for (;;) { \
set_current_state(TASK_INTERRUPTIBLE); \
if (condition) \
break; \
if (!signal_pending(current)) { \
schedule(); \
continue; \
} \
ret = -ERESTARTSYS; \
break; \
} \
current->state = TASK_RUNNING; \
remove_wait_queue(&wq, &__wait); \
} while (0)
#define wait_event_interruptible_exclusive(wq, condition) \
({ \
int __ret = 0; \
if (!(condition)) \
__wait_event_interruptible_exclusive(wq, condition, __ret);\
__ret; \
})
/*
* Must be called with the spinlock in the wait_queue_head_t held.
*/
static inline void add_wait_queue_exclusive_locked(wait_queue_head_t *q,
wait_queue_t * wait)
{
wait->flags |= WQ_FLAG_EXCLUSIVE;
__add_wait_queue_tail(q, wait);
}
/*
* Must be called with the spinlock in the wait_queue_head_t held.
*/
static inline void remove_wait_queue_locked(wait_queue_head_t *q,
wait_queue_t * wait)
{
__remove_wait_queue(q, wait);
}
/*
* These are the old interfaces to sleep waiting for an event.
* They are racy. DO NOT use them, use the wait_event* interfaces above.
* We plan to remove these interfaces during 2.7.
*/
extern void FASTCALL(sleep_on(wait_queue_head_t *q));
extern long FASTCALL(sleep_on_timeout(wait_queue_head_t *q,
signed long timeout));
extern void FASTCALL(interruptible_sleep_on(wait_queue_head_t *q));
extern long FASTCALL(interruptible_sleep_on_timeout(wait_queue_head_t *q,
signed long timeout));
/*
* Waitqueues which are removed from the waitqueue_head at wakeup time
*/
void FASTCALL(prepare_to_wait(wait_queue_head_t *q,
wait_queue_t *wait, int state));
void FASTCALL(prepare_to_wait_exclusive(wait_queue_head_t *q,
wait_queue_t *wait, int state));
void FASTCALL(finish_wait(wait_queue_head_t *q, wait_queue_t *wait));
int autoremove_wake_function(wait_queue_t *wait, unsigned mode, int sync, void *key);
#define DEFINE_WAIT(name) \
wait_queue_t name = { \
.task = current, \
.func = autoremove_wake_function, \
.task_list = { .next = &name.task_list, \
.prev = &name.task_list, \
}, \
}
#define init_wait(wait) \
do { \
wait->task = current; \
wait->func = autoremove_wake_function; \
INIT_LIST_HEAD(&wait->task_list); \
} while (0)
#endif /* __KERNEL__ */
#endif
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