#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/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);
-extern int default_wake_function(wait_queue_t *wait, unsigned mode, int sync);
+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;
+ 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;
+struct task_struct;
/*
* Macros for declaration and initialisaton of the datatypes
*/
#define __WAITQUEUE_INITIALIZER(name, tsk) { \
- .task = tsk, \
+ .private = tsk, \
.func = default_wake_function, \
.task_list = { NULL, NULL } }
#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)
{
- q->lock = SPIN_LOCK_UNLOCKED;
+ 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->task = p;
+ q->private = p;
q->func = default_wake_function;
}
wait_queue_func_t func)
{
q->flags = 0;
- q->task = NULL;
+ q->private = NULL;
q->func = func;
}
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));
+extern int 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_del(&old->task_list);
}
-extern void FASTCALL(__wake_up(wait_queue_head_t *q, unsigned int mode, int nr));
+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)
-#define wake_up_nr(x, nr) __wake_up((x),TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE, nr)
-#define wake_up_all(x) __wake_up((x),TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE, 0)
-#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)
-#define wake_up_interruptible_nr(x, nr) __wake_up((x),TASK_INTERRUPTIBLE, nr)
-#define wake_up_interruptible_all(x) __wake_up((x),TASK_INTERRUPTIBLE, 0)
+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 { \
- wait_queue_t __wait; \
- init_waitqueue_entry(&__wait, current); \
+ DEFINE_WAIT(__wait); \
\
- add_wait_queue(&wq, &__wait); \
for (;;) { \
- set_current_state(TASK_UNINTERRUPTIBLE); \
+ prepare_to_wait(&wq, &__wait, TASK_UNINTERRUPTIBLE); \
if (condition) \
break; \
schedule(); \
} \
- current->state = TASK_RUNNING; \
- remove_wait_queue(&wq, &__wait); \
+ 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) \
__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 { \
- wait_queue_t __wait; \
- init_waitqueue_entry(&__wait, current); \
+ DEFINE_WAIT(__wait); \
\
- add_wait_queue(&wq, &__wait); \
for (;;) { \
- set_current_state(TASK_INTERRUPTIBLE); \
+ prepare_to_wait(&wq, &__wait, TASK_INTERRUPTIBLE); \
if (condition) \
break; \
if (!signal_pending(current)) { \
ret = -ERESTARTSYS; \
break; \
} \
- current->state = TASK_RUNNING; \
- remove_wait_queue(&wq, &__wait); \
+ 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; \
#define __wait_event_interruptible_timeout(wq, condition, ret) \
do { \
- wait_queue_t __wait; \
- init_waitqueue_entry(&__wait, current); \
+ DEFINE_WAIT(__wait); \
\
- add_wait_queue(&wq, &__wait); \
for (;;) { \
- set_current_state(TASK_INTERRUPTIBLE); \
+ prepare_to_wait(&wq, &__wait, TASK_INTERRUPTIBLE); \
if (condition) \
break; \
if (!signal_pending(current)) { \
ret = -ERESTARTSYS; \
break; \
} \
- current->state = TASK_RUNNING; \
- remove_wait_queue(&wq, &__wait); \
+ 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; \
__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.
*/
* 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,
+extern void __deprecated FASTCALL(sleep_on(wait_queue_head_t *q));
+extern long __deprecated FASTCALL(sleep_on_timeout(wait_queue_head_t *q,
signed long timeout));
-extern void FASTCALL(interruptible_sleep_on(wait_queue_head_t *q));
+extern void __deprecated FASTCALL(interruptible_sleep_on(wait_queue_head_t *q));
extern long FASTCALL(interruptible_sleep_on_timeout(wait_queue_head_t *q,
signed long timeout));
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);
+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 = { \
- .task = current, \
+ .private = current, \
.func = autoremove_wake_function, \
- .task_list = { .next = &name.task_list, \
- .prev = &name.task_list, \
- }, \
+ .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->task = current; \
- wait->func = autoremove_wake_function; \
- INIT_LIST_HEAD(&wait->task_list); \
+ (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__ */
git://git.onelab.eu / linux-2.6.git / blobdiff