| #ifndef _LINUX_WAIT_H |
| #define _LINUX_WAIT_H |
| |
| #define WNOHANG 0x00000001 |
| #define WUNTRACED 0x00000002 |
| #define WSTOPPED WUNTRACED |
| #define WEXITED 0x00000004 |
| #define WCONTINUED 0x00000008 |
| #define WNOWAIT 0x01000000 /* Don't reap, just poll status. */ |
| |
| #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 */ |
| |
| /* First argument to waitid: */ |
| #define P_ALL 0 |
| #define P_PID 1 |
| #define P_PGID 2 |
| |
| #ifdef __KERNEL__ |
| |
| #include <linux/config.h> |
| #include <linux/list.h> |
| #include <linux/stddef.h> |
| #include <linux/spinlock.h> |
| #include <asm/system.h> |
| #include <asm/current.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 |
| void *private; |
| wait_queue_func_t func; |
| struct list_head task_list; |
| }; |
| |
| struct wait_bit_key { |
| void *flags; |
| int bit_nr; |
| }; |
| |
| struct wait_bit_queue { |
| struct wait_bit_key key; |
| wait_queue_t wait; |
| }; |
| |
| 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) { \ |
| .private = 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) |
| |
| #define __WAIT_BIT_KEY_INITIALIZER(word, bit) \ |
| { .flags = word, .bit_nr = bit, } |
| |
| static inline void init_waitqueue_head(wait_queue_head_t *q) |
| { |
| spin_lock_init(&q->lock); |
| INIT_LIST_HEAD(&q->task_list); |
| } |
| |
| static inline void init_waitqueue_entry(wait_queue_t *q, struct task_struct *p) |
| { |
| q->flags = 0; |
| q->private = 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->private = NULL; |
| q->func = func; |
| } |
| |
| static inline int waitqueue_active(wait_queue_head_t *q) |
| { |
| return !list_empty(&q->task_list); |
| } |
| |
| /* |
| * Used to distinguish between sync and async io wait context: |
| * sync i/o typically specifies a NULL wait queue entry or a wait |
| * queue entry bound to a task (current task) to wake up. |
| * aio specifies a wait queue entry with an async notification |
| * callback routine, not associated with any task. |
| */ |
| #define is_sync_wait(wait) (!(wait) || ((wait)->private)) |
| |
| 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)); |
| void FASTCALL(__wake_up_bit(wait_queue_head_t *, void *, int)); |
| int FASTCALL(__wait_on_bit(wait_queue_head_t *, struct wait_bit_queue *, int (*)(void *), unsigned)); |
| int FASTCALL(__wait_on_bit_lock(wait_queue_head_t *, struct wait_bit_queue *, int (*)(void *), unsigned)); |
| void FASTCALL(wake_up_bit(void *, int)); |
| int FASTCALL(out_of_line_wait_on_bit(void *, int, int (*)(void *), unsigned)); |
| int FASTCALL(out_of_line_wait_on_bit_lock(void *, int, int (*)(void *), unsigned)); |
| wait_queue_head_t *FASTCALL(bit_waitqueue(void *, int)); |
| |
| #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_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 { \ |
| DEFINE_WAIT(__wait); \ |
| \ |
| for (;;) { \ |
| prepare_to_wait(&wq, &__wait, TASK_UNINTERRUPTIBLE); \ |
| if (condition) \ |
| break; \ |
| schedule(); \ |
| } \ |
| finish_wait(&wq, &__wait); \ |
| } while (0) |
| |
| /** |
| * wait_event - sleep until a condition gets true |
| * @wq: the waitqueue to wait on |
| * @condition: a C expression for the event to wait for |
| * |
| * The process is put to sleep (TASK_UNINTERRUPTIBLE) until the |
| * @condition evaluates to true. The @condition is checked each time |
| * the waitqueue @wq is woken up. |
| * |
| * wake_up() has to be called after changing any variable that could |
| * change the result of the wait condition. |
| */ |
| #define wait_event(wq, condition) \ |
| do { \ |
| if (condition) \ |
| break; \ |
| __wait_event(wq, condition); \ |
| } while (0) |
| |
| #define __wait_event_timeout(wq, condition, ret) \ |
| do { \ |
| DEFINE_WAIT(__wait); \ |
| \ |
| for (;;) { \ |
| prepare_to_wait(&wq, &__wait, TASK_UNINTERRUPTIBLE); \ |
| if (condition) \ |
| break; \ |
| ret = schedule_timeout(ret); \ |
| if (!ret) \ |
| break; \ |
| } \ |
| finish_wait(&wq, &__wait); \ |
| } while (0) |
| |
| /** |
| * wait_event_timeout - sleep until a condition gets true or a timeout elapses |
| * @wq: the waitqueue to wait on |
| * @condition: a C expression for the event to wait for |
| * @timeout: timeout, in jiffies |
| * |
| * The process is put to sleep (TASK_UNINTERRUPTIBLE) until the |
| * @condition evaluates to true. The @condition is checked each time |
| * the waitqueue @wq is woken up. |
| * |
| * wake_up() has to be called after changing any variable that could |
| * change the result of the wait condition. |
| * |
| * The function returns 0 if the @timeout elapsed, and the remaining |
| * jiffies if the condition evaluated to true before the timeout elapsed. |
| */ |
| #define wait_event_timeout(wq, condition, timeout) \ |
| ({ \ |
| long __ret = timeout; \ |
| if (!(condition)) \ |
| __wait_event_timeout(wq, condition, __ret); \ |
| __ret; \ |
| }) |
| |
| #define __wait_event_interruptible(wq, condition, ret) \ |
| do { \ |
| DEFINE_WAIT(__wait); \ |
| \ |
| for (;;) { \ |
| prepare_to_wait(&wq, &__wait, TASK_INTERRUPTIBLE); \ |
| if (condition) \ |
| break; \ |
| if (!signal_pending(current)) { \ |
| schedule(); \ |
| continue; \ |
| } \ |
| ret = -ERESTARTSYS; \ |
| break; \ |
| } \ |
| finish_wait(&wq, &__wait); \ |
| } while (0) |
| |
| /** |
| * wait_event_interruptible - sleep until a condition gets true |
| * @wq: the waitqueue to wait on |
| * @condition: a C expression for the event to wait for |
| * |
| * The process is put to sleep (TASK_INTERRUPTIBLE) until the |
| * @condition evaluates to true or a signal is received. |
| * The @condition is checked each time the waitqueue @wq is woken up. |
| * |
| * wake_up() has to be called after changing any variable that could |
| * change the result of the wait condition. |
| * |
| * The function will return -ERESTARTSYS if it was interrupted by a |
| * signal and 0 if @condition evaluated to true. |
| */ |
| #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 { \ |
| DEFINE_WAIT(__wait); \ |
| \ |
| for (;;) { \ |
| prepare_to_wait(&wq, &__wait, TASK_INTERRUPTIBLE); \ |
| if (condition) \ |
| break; \ |
| if (!signal_pending(current)) { \ |
| ret = schedule_timeout(ret); \ |
| if (!ret) \ |
| break; \ |
| continue; \ |
| } \ |
| ret = -ERESTARTSYS; \ |
| break; \ |
| } \ |
| finish_wait(&wq, &__wait); \ |
| } while (0) |
| |
| /** |
| * wait_event_interruptible_timeout - sleep until a condition gets true or a timeout elapses |
| * @wq: the waitqueue to wait on |
| * @condition: a C expression for the event to wait for |
| * @timeout: timeout, in jiffies |
| * |
| * The process is put to sleep (TASK_INTERRUPTIBLE) until the |
| * @condition evaluates to true or a signal is received. |
| * The @condition is checked each time the waitqueue @wq is woken up. |
| * |
| * wake_up() has to be called after changing any variable that could |
| * change the result of the wait condition. |
| * |
| * The function returns 0 if the @timeout elapsed, -ERESTARTSYS if it |
| * was interrupted by a signal, and the remaining jiffies otherwise |
| * if the condition evaluated to true before the timeout elapsed. |
| */ |
| #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 { \ |
| DEFINE_WAIT(__wait); \ |
| \ |
| for (;;) { \ |
| prepare_to_wait_exclusive(&wq, &__wait, \ |
| TASK_INTERRUPTIBLE); \ |
| if (condition) \ |
| break; \ |
| if (!signal_pending(current)) { \ |
| schedule(); \ |
| continue; \ |
| } \ |
| ret = -ERESTARTSYS; \ |
| break; \ |
| } \ |
| finish_wait(&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); |
| int wake_bit_function(wait_queue_t *wait, unsigned mode, int sync, void *key); |
| |
| #define DEFINE_WAIT(name) \ |
| wait_queue_t name = { \ |
| .private = current, \ |
| .func = autoremove_wake_function, \ |
| .task_list = LIST_HEAD_INIT((name).task_list), \ |
| } |
| |
| #define DEFINE_WAIT_BIT(name, word, bit) \ |
| struct wait_bit_queue name = { \ |
| .key = __WAIT_BIT_KEY_INITIALIZER(word, bit), \ |
| .wait = { \ |
| .private = current, \ |
| .func = wake_bit_function, \ |
| .task_list = \ |
| LIST_HEAD_INIT((name).wait.task_list), \ |
| }, \ |
| } |
| |
| #define init_wait(wait) \ |
| do { \ |
| (wait)->private = current; \ |
| (wait)->func = autoremove_wake_function; \ |
| INIT_LIST_HEAD(&(wait)->task_list); \ |
| } while (0) |
| |
| /** |
| * wait_on_bit - wait for a bit to be cleared |
| * @word: the word being waited on, a kernel virtual address |
| * @bit: the bit of the word being waited on |
| * @action: the function used to sleep, which may take special actions |
| * @mode: the task state to sleep in |
| * |
| * There is a standard hashed waitqueue table for generic use. This |
| * is the part of the hashtable's accessor API that waits on a bit. |
| * For instance, if one were to have waiters on a bitflag, one would |
| * call wait_on_bit() in threads waiting for the bit to clear. |
| * One uses wait_on_bit() where one is waiting for the bit to clear, |
| * but has no intention of setting it. |
| */ |
| static inline int wait_on_bit(void *word, int bit, |
| int (*action)(void *), unsigned mode) |
| { |
| if (!test_bit(bit, word)) |
| return 0; |
| return out_of_line_wait_on_bit(word, bit, action, mode); |
| } |
| |
| /** |
| * wait_on_bit_lock - wait for a bit to be cleared, when wanting to set it |
| * @word: the word being waited on, a kernel virtual address |
| * @bit: the bit of the word being waited on |
| * @action: the function used to sleep, which may take special actions |
| * @mode: the task state to sleep in |
| * |
| * There is a standard hashed waitqueue table for generic use. This |
| * is the part of the hashtable's accessor API that waits on a bit |
| * when one intends to set it, for instance, trying to lock bitflags. |
| * For instance, if one were to have waiters trying to set bitflag |
| * and waiting for it to clear before setting it, one would call |
| * wait_on_bit() in threads waiting to be able to set the bit. |
| * One uses wait_on_bit_lock() where one is waiting for the bit to |
| * clear with the intention of setting it, and when done, clearing it. |
| */ |
| static inline int wait_on_bit_lock(void *word, int bit, |
| int (*action)(void *), unsigned mode) |
| { |
| if (!test_and_set_bit(bit, word)) |
| return 0; |
| return out_of_line_wait_on_bit_lock(word, bit, action, mode); |
| } |
| |
| #endif /* __KERNEL__ */ |
| |
| #endif |