X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=include%2Flinux%2Fwait.h;h=34f41e7901ff9c392cc1741f269be82c22b9ff83;hb=43bc926fffd92024b46cafaf7350d669ba9ca884;hp=21cd4df67b241845cbc71bd6c8997d52b4938c8d;hpb=c7b5ebbddf7bcd3651947760f423e3783bbe6573;p=linux-2.6.git diff --git a/include/linux/wait.h b/include/linux/wait.h index 21cd4df67..34f41e790 100644 --- a/include/linux/wait.h +++ b/include/linux/wait.h @@ -24,6 +24,7 @@ #include #include #include +#include typedef struct __wait_queue wait_queue_t; typedef int (*wait_queue_func_t)(wait_queue_t *wait, unsigned mode, int sync, void *key); @@ -32,24 +33,35 @@ 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 } } @@ -63,16 +75,19 @@ typedef struct __wait_queue_head wait_queue_head_t; #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; } @@ -80,7 +95,7 @@ static inline void init_waitqueue_func_entry(wait_queue_t *q, wait_queue_func_t func) { q->flags = 0; - q->task = NULL; + q->private = NULL; q->func = func; } @@ -96,11 +111,11 @@ static inline int waitqueue_active(wait_queue_head_t *q) * aio specifies a wait queue entry with an async notification * callback routine, not associated with any task. */ -#define is_sync_wait(wait) (!(wait) || ((wait)->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) { @@ -125,11 +140,17 @@ static inline void __remove_wait_queue(wait_queue_head_t *head, 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_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) @@ -149,6 +170,18 @@ do { \ 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) \ @@ -171,6 +204,22 @@ do { \ 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; \ @@ -197,6 +246,21 @@ do { \ 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; \ @@ -225,6 +289,23 @@ do { \ 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; \ @@ -284,10 +365,10 @@ static inline void remove_wait_queue_locked(wait_queue_head_t *q, * 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)); @@ -300,22 +381,78 @@ 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 = { \ - .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__ */