| /* SPDX-License-Identifier: GPL-2.0 */ |
| #ifndef _LINUX_WAIT_H |
| #define _LINUX_WAIT_H |
| /* |
| * Linux wait queue related types and methods |
| */ |
| #include <linux/list.h> |
| #include <linux/stddef.h> |
| #include <linux/spinlock.h> |
| |
| #include <asm/current.h> |
| #include <uapi/linux/wait.h> |
| |
| typedef struct wait_queue_entry wait_queue_entry_t; |
| |
| typedef int (*wait_queue_func_t)(struct wait_queue_entry *wq_entry, unsigned mode, int flags, void *key); |
| int default_wake_function(struct wait_queue_entry *wq_entry, unsigned mode, int flags, void *key); |
| |
| /* wait_queue_entry::flags */ |
| #define WQ_FLAG_EXCLUSIVE 0x01 |
| #define WQ_FLAG_WOKEN 0x02 |
| #define WQ_FLAG_BOOKMARK 0x04 |
| #define WQ_FLAG_CUSTOM 0x08 |
| #define WQ_FLAG_DONE 0x10 |
| #define WQ_FLAG_PRIORITY 0x20 |
| |
| /* |
| * A single wait-queue entry structure: |
| */ |
| struct wait_queue_entry { |
| unsigned int flags; |
| void *private; |
| wait_queue_func_t func; |
| struct list_head entry; |
| }; |
| |
| struct wait_queue_head { |
| spinlock_t lock; |
| struct list_head head; |
| }; |
| 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) { \ |
| .private = tsk, \ |
| .func = default_wake_function, \ |
| .entry = { NULL, NULL } } |
| |
| #define DECLARE_WAITQUEUE(name, tsk) \ |
| struct wait_queue_entry name = __WAITQUEUE_INITIALIZER(name, tsk) |
| |
| #define __WAIT_QUEUE_HEAD_INITIALIZER(name) { \ |
| .lock = __SPIN_LOCK_UNLOCKED(name.lock), \ |
| .head = { &(name).head, &(name).head } } |
| |
| #define DECLARE_WAIT_QUEUE_HEAD(name) \ |
| struct wait_queue_head name = __WAIT_QUEUE_HEAD_INITIALIZER(name) |
| |
| extern void __init_waitqueue_head(struct wait_queue_head *wq_head, const char *name, struct lock_class_key *); |
| |
| #define init_waitqueue_head(wq_head) \ |
| do { \ |
| static struct lock_class_key __key; \ |
| \ |
| __init_waitqueue_head((wq_head), #wq_head, &__key); \ |
| } while (0) |
| |
| #ifdef CONFIG_LOCKDEP |
| # define __WAIT_QUEUE_HEAD_INIT_ONSTACK(name) \ |
| ({ init_waitqueue_head(&name); name; }) |
| # define DECLARE_WAIT_QUEUE_HEAD_ONSTACK(name) \ |
| struct wait_queue_head name = __WAIT_QUEUE_HEAD_INIT_ONSTACK(name) |
| #else |
| # define DECLARE_WAIT_QUEUE_HEAD_ONSTACK(name) DECLARE_WAIT_QUEUE_HEAD(name) |
| #endif |
| |
| static inline void init_waitqueue_entry(struct wait_queue_entry *wq_entry, struct task_struct *p) |
| { |
| wq_entry->flags = 0; |
| wq_entry->private = p; |
| wq_entry->func = default_wake_function; |
| } |
| |
| static inline void |
| init_waitqueue_func_entry(struct wait_queue_entry *wq_entry, wait_queue_func_t func) |
| { |
| wq_entry->flags = 0; |
| wq_entry->private = NULL; |
| wq_entry->func = func; |
| } |
| |
| /** |
| * waitqueue_active -- locklessly test for waiters on the queue |
| * @wq_head: the waitqueue to test for waiters |
| * |
| * returns true if the wait list is not empty |
| * |
| * NOTE: this function is lockless and requires care, incorrect usage _will_ |
| * lead to sporadic and non-obvious failure. |
| * |
| * Use either while holding wait_queue_head::lock or when used for wakeups |
| * with an extra smp_mb() like:: |
| * |
| * CPU0 - waker CPU1 - waiter |
| * |
| * for (;;) { |
| * @cond = true; prepare_to_wait(&wq_head, &wait, state); |
| * smp_mb(); // smp_mb() from set_current_state() |
| * if (waitqueue_active(wq_head)) if (@cond) |
| * wake_up(wq_head); break; |
| * schedule(); |
| * } |
| * finish_wait(&wq_head, &wait); |
| * |
| * Because without the explicit smp_mb() it's possible for the |
| * waitqueue_active() load to get hoisted over the @cond store such that we'll |
| * observe an empty wait list while the waiter might not observe @cond. |
| * |
| * Also note that this 'optimization' trades a spin_lock() for an smp_mb(), |
| * which (when the lock is uncontended) are of roughly equal cost. |
| */ |
| static inline int waitqueue_active(struct wait_queue_head *wq_head) |
| { |
| return !list_empty(&wq_head->head); |
| } |
| |
| /** |
| * wq_has_single_sleeper - check if there is only one sleeper |
| * @wq_head: wait queue head |
| * |
| * Returns true of wq_head has only one sleeper on the list. |
| * |
| * Please refer to the comment for waitqueue_active. |
| */ |
| static inline bool wq_has_single_sleeper(struct wait_queue_head *wq_head) |
| { |
| return list_is_singular(&wq_head->head); |
| } |
| |
| /** |
| * wq_has_sleeper - check if there are any waiting processes |
| * @wq_head: wait queue head |
| * |
| * Returns true if wq_head has waiting processes |
| * |
| * Please refer to the comment for waitqueue_active. |
| */ |
| static inline bool wq_has_sleeper(struct wait_queue_head *wq_head) |
| { |
| /* |
| * We need to be sure we are in sync with the |
| * add_wait_queue modifications to the wait queue. |
| * |
| * This memory barrier should be paired with one on the |
| * waiting side. |
| */ |
| smp_mb(); |
| return waitqueue_active(wq_head); |
| } |
| |
| extern void add_wait_queue(struct wait_queue_head *wq_head, struct wait_queue_entry *wq_entry); |
| extern void add_wait_queue_exclusive(struct wait_queue_head *wq_head, struct wait_queue_entry *wq_entry); |
| extern void add_wait_queue_priority(struct wait_queue_head *wq_head, struct wait_queue_entry *wq_entry); |
| extern void remove_wait_queue(struct wait_queue_head *wq_head, struct wait_queue_entry *wq_entry); |
| |
| static inline void __add_wait_queue(struct wait_queue_head *wq_head, struct wait_queue_entry *wq_entry) |
| { |
| struct list_head *head = &wq_head->head; |
| struct wait_queue_entry *wq; |
| |
| list_for_each_entry(wq, &wq_head->head, entry) { |
| if (!(wq->flags & WQ_FLAG_PRIORITY)) |
| break; |
| head = &wq->entry; |
| } |
| list_add(&wq_entry->entry, head); |
| } |
| |
| /* |
| * Used for wake-one threads: |
| */ |
| static inline void |
| __add_wait_queue_exclusive(struct wait_queue_head *wq_head, struct wait_queue_entry *wq_entry) |
| { |
| wq_entry->flags |= WQ_FLAG_EXCLUSIVE; |
| __add_wait_queue(wq_head, wq_entry); |
| } |
| |
| static inline void __add_wait_queue_entry_tail(struct wait_queue_head *wq_head, struct wait_queue_entry *wq_entry) |
| { |
| list_add_tail(&wq_entry->entry, &wq_head->head); |
| } |
| |
| static inline void |
| __add_wait_queue_entry_tail_exclusive(struct wait_queue_head *wq_head, struct wait_queue_entry *wq_entry) |
| { |
| wq_entry->flags |= WQ_FLAG_EXCLUSIVE; |
| __add_wait_queue_entry_tail(wq_head, wq_entry); |
| } |
| |
| static inline void |
| __remove_wait_queue(struct wait_queue_head *wq_head, struct wait_queue_entry *wq_entry) |
| { |
| list_del(&wq_entry->entry); |
| } |
| |
| void __wake_up(struct wait_queue_head *wq_head, unsigned int mode, int nr, void *key); |
| void __wake_up_locked_key(struct wait_queue_head *wq_head, unsigned int mode, void *key); |
| void __wake_up_locked_key_bookmark(struct wait_queue_head *wq_head, |
| unsigned int mode, void *key, wait_queue_entry_t *bookmark); |
| void __wake_up_sync_key(struct wait_queue_head *wq_head, unsigned int mode, void *key); |
| void __wake_up_locked_sync_key(struct wait_queue_head *wq_head, unsigned int mode, void *key); |
| void __wake_up_locked(struct wait_queue_head *wq_head, unsigned int mode, int nr); |
| void __wake_up_sync(struct wait_queue_head *wq_head, unsigned int mode); |
| |
| #define wake_up(x) __wake_up(x, TASK_NORMAL, 1, NULL) |
| #define wake_up_nr(x, nr) __wake_up(x, TASK_NORMAL, nr, NULL) |
| #define wake_up_all(x) __wake_up(x, TASK_NORMAL, 0, NULL) |
| #define wake_up_locked(x) __wake_up_locked((x), TASK_NORMAL, 1) |
| #define wake_up_all_locked(x) __wake_up_locked((x), TASK_NORMAL, 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_interruptible_sync(x) __wake_up_sync((x), TASK_INTERRUPTIBLE) |
| |
| /* |
| * Wakeup macros to be used to report events to the targets. |
| */ |
| #define poll_to_key(m) ((void *)(__force uintptr_t)(__poll_t)(m)) |
| #define key_to_poll(m) ((__force __poll_t)(uintptr_t)(void *)(m)) |
| #define wake_up_poll(x, m) \ |
| __wake_up(x, TASK_NORMAL, 1, poll_to_key(m)) |
| #define wake_up_locked_poll(x, m) \ |
| __wake_up_locked_key((x), TASK_NORMAL, poll_to_key(m)) |
| #define wake_up_interruptible_poll(x, m) \ |
| __wake_up(x, TASK_INTERRUPTIBLE, 1, poll_to_key(m)) |
| #define wake_up_interruptible_sync_poll(x, m) \ |
| __wake_up_sync_key((x), TASK_INTERRUPTIBLE, poll_to_key(m)) |
| #define wake_up_interruptible_sync_poll_locked(x, m) \ |
| __wake_up_locked_sync_key((x), TASK_INTERRUPTIBLE, poll_to_key(m)) |
| |
| #define ___wait_cond_timeout(condition) \ |
| ({ \ |
| bool __cond = (condition); \ |
| if (__cond && !__ret) \ |
| __ret = 1; \ |
| __cond || !__ret; \ |
| }) |
| |
| #define ___wait_is_interruptible(state) \ |
| (!__builtin_constant_p(state) || \ |
| state == TASK_INTERRUPTIBLE || state == TASK_KILLABLE) \ |
| |
| extern void init_wait_entry(struct wait_queue_entry *wq_entry, int flags); |
| |
| /* |
| * The below macro ___wait_event() has an explicit shadow of the __ret |
| * variable when used from the wait_event_*() macros. |
| * |
| * This is so that both can use the ___wait_cond_timeout() construct |
| * to wrap the condition. |
| * |
| * The type inconsistency of the wait_event_*() __ret variable is also |
| * on purpose; we use long where we can return timeout values and int |
| * otherwise. |
| */ |
| |
| #define ___wait_event(wq_head, condition, state, exclusive, ret, cmd) \ |
| ({ \ |
| __label__ __out; \ |
| struct wait_queue_entry __wq_entry; \ |
| long __ret = ret; /* explicit shadow */ \ |
| \ |
| init_wait_entry(&__wq_entry, exclusive ? WQ_FLAG_EXCLUSIVE : 0); \ |
| for (;;) { \ |
| long __int = prepare_to_wait_event(&wq_head, &__wq_entry, state);\ |
| \ |
| if (condition) \ |
| break; \ |
| \ |
| if (___wait_is_interruptible(state) && __int) { \ |
| __ret = __int; \ |
| goto __out; \ |
| } \ |
| \ |
| cmd; \ |
| } \ |
| finish_wait(&wq_head, &__wq_entry); \ |
| __out: __ret; \ |
| }) |
| |
| #define __wait_event(wq_head, condition) \ |
| (void)___wait_event(wq_head, condition, TASK_UNINTERRUPTIBLE, 0, 0, \ |
| schedule()) |
| |
| /** |
| * wait_event - sleep until a condition gets true |
| * @wq_head: 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_head 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_head, condition) \ |
| do { \ |
| might_sleep(); \ |
| if (condition) \ |
| break; \ |
| __wait_event(wq_head, condition); \ |
| } while (0) |
| |
| #define __io_wait_event(wq_head, condition) \ |
| (void)___wait_event(wq_head, condition, TASK_UNINTERRUPTIBLE, 0, 0, \ |
| io_schedule()) |
| |
| /* |
| * io_wait_event() -- like wait_event() but with io_schedule() |
| */ |
| #define io_wait_event(wq_head, condition) \ |
| do { \ |
| might_sleep(); \ |
| if (condition) \ |
| break; \ |
| __io_wait_event(wq_head, condition); \ |
| } while (0) |
| |
| #define __wait_event_freezable(wq_head, condition) \ |
| ___wait_event(wq_head, condition, TASK_INTERRUPTIBLE, 0, 0, \ |
| freezable_schedule()) |
| |
| /** |
| * wait_event_freezable - sleep (or freeze) until a condition gets true |
| * @wq_head: the waitqueue to wait on |
| * @condition: a C expression for the event to wait for |
| * |
| * The process is put to sleep (TASK_INTERRUPTIBLE -- so as not to contribute |
| * to system load) until the @condition evaluates to true. The |
| * @condition is checked each time the waitqueue @wq_head 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_freezable(wq_head, condition) \ |
| ({ \ |
| int __ret = 0; \ |
| might_sleep(); \ |
| if (!(condition)) \ |
| __ret = __wait_event_freezable(wq_head, condition); \ |
| __ret; \ |
| }) |
| |
| #define __wait_event_timeout(wq_head, condition, timeout) \ |
| ___wait_event(wq_head, ___wait_cond_timeout(condition), \ |
| TASK_UNINTERRUPTIBLE, 0, timeout, \ |
| __ret = schedule_timeout(__ret)) |
| |
| /** |
| * wait_event_timeout - sleep until a condition gets true or a timeout elapses |
| * @wq_head: 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_head is woken up. |
| * |
| * wake_up() has to be called after changing any variable that could |
| * change the result of the wait condition. |
| * |
| * Returns: |
| * 0 if the @condition evaluated to %false after the @timeout elapsed, |
| * 1 if the @condition evaluated to %true after the @timeout elapsed, |
| * or the remaining jiffies (at least 1) if the @condition evaluated |
| * to %true before the @timeout elapsed. |
| */ |
| #define wait_event_timeout(wq_head, condition, timeout) \ |
| ({ \ |
| long __ret = timeout; \ |
| might_sleep(); \ |
| if (!___wait_cond_timeout(condition)) \ |
| __ret = __wait_event_timeout(wq_head, condition, timeout); \ |
| __ret; \ |
| }) |
| |
| #define __wait_event_freezable_timeout(wq_head, condition, timeout) \ |
| ___wait_event(wq_head, ___wait_cond_timeout(condition), \ |
| TASK_INTERRUPTIBLE, 0, timeout, \ |
| __ret = freezable_schedule_timeout(__ret)) |
| |
| /* |
| * like wait_event_timeout() -- except it uses TASK_INTERRUPTIBLE to avoid |
| * increasing load and is freezable. |
| */ |
| #define wait_event_freezable_timeout(wq_head, condition, timeout) \ |
| ({ \ |
| long __ret = timeout; \ |
| might_sleep(); \ |
| if (!___wait_cond_timeout(condition)) \ |
| __ret = __wait_event_freezable_timeout(wq_head, condition, timeout); \ |
| __ret; \ |
| }) |
| |
| #define __wait_event_exclusive_cmd(wq_head, condition, cmd1, cmd2) \ |
| (void)___wait_event(wq_head, condition, TASK_UNINTERRUPTIBLE, 1, 0, \ |
| cmd1; schedule(); cmd2) |
| /* |
| * Just like wait_event_cmd(), except it sets exclusive flag |
| */ |
| #define wait_event_exclusive_cmd(wq_head, condition, cmd1, cmd2) \ |
| do { \ |
| if (condition) \ |
| break; \ |
| __wait_event_exclusive_cmd(wq_head, condition, cmd1, cmd2); \ |
| } while (0) |
| |
| #define __wait_event_cmd(wq_head, condition, cmd1, cmd2) \ |
| (void)___wait_event(wq_head, condition, TASK_UNINTERRUPTIBLE, 0, 0, \ |
| cmd1; schedule(); cmd2) |
| |
| /** |
| * wait_event_cmd - sleep until a condition gets true |
| * @wq_head: the waitqueue to wait on |
| * @condition: a C expression for the event to wait for |
| * @cmd1: the command will be executed before sleep |
| * @cmd2: the command will be executed after sleep |
| * |
| * The process is put to sleep (TASK_UNINTERRUPTIBLE) until the |
| * @condition evaluates to true. The @condition is checked each time |
| * the waitqueue @wq_head 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_cmd(wq_head, condition, cmd1, cmd2) \ |
| do { \ |
| if (condition) \ |
| break; \ |
| __wait_event_cmd(wq_head, condition, cmd1, cmd2); \ |
| } while (0) |
| |
| #define __wait_event_interruptible(wq_head, condition) \ |
| ___wait_event(wq_head, condition, TASK_INTERRUPTIBLE, 0, 0, \ |
| schedule()) |
| |
| /** |
| * wait_event_interruptible - sleep until a condition gets true |
| * @wq_head: 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_head 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_head, condition) \ |
| ({ \ |
| int __ret = 0; \ |
| might_sleep(); \ |
| if (!(condition)) \ |
| __ret = __wait_event_interruptible(wq_head, condition); \ |
| __ret; \ |
| }) |
| |
| #define __wait_event_interruptible_timeout(wq_head, condition, timeout) \ |
| ___wait_event(wq_head, ___wait_cond_timeout(condition), \ |
| TASK_INTERRUPTIBLE, 0, timeout, \ |
| __ret = schedule_timeout(__ret)) |
| |
| /** |
| * wait_event_interruptible_timeout - sleep until a condition gets true or a timeout elapses |
| * @wq_head: 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_head is woken up. |
| * |
| * wake_up() has to be called after changing any variable that could |
| * change the result of the wait condition. |
| * |
| * Returns: |
| * 0 if the @condition evaluated to %false after the @timeout elapsed, |
| * 1 if the @condition evaluated to %true after the @timeout elapsed, |
| * the remaining jiffies (at least 1) if the @condition evaluated |
| * to %true before the @timeout elapsed, or -%ERESTARTSYS if it was |
| * interrupted by a signal. |
| */ |
| #define wait_event_interruptible_timeout(wq_head, condition, timeout) \ |
| ({ \ |
| long __ret = timeout; \ |
| might_sleep(); \ |
| if (!___wait_cond_timeout(condition)) \ |
| __ret = __wait_event_interruptible_timeout(wq_head, \ |
| condition, timeout); \ |
| __ret; \ |
| }) |
| |
| #define __wait_event_hrtimeout(wq_head, condition, timeout, state) \ |
| ({ \ |
| int __ret = 0; \ |
| struct hrtimer_sleeper __t; \ |
| \ |
| hrtimer_init_sleeper_on_stack(&__t, CLOCK_MONOTONIC, \ |
| HRTIMER_MODE_REL); \ |
| if ((timeout) != KTIME_MAX) \ |
| hrtimer_start_range_ns(&__t.timer, timeout, \ |
| current->timer_slack_ns, \ |
| HRTIMER_MODE_REL); \ |
| \ |
| __ret = ___wait_event(wq_head, condition, state, 0, 0, \ |
| if (!__t.task) { \ |
| __ret = -ETIME; \ |
| break; \ |
| } \ |
| schedule()); \ |
| \ |
| hrtimer_cancel(&__t.timer); \ |
| destroy_hrtimer_on_stack(&__t.timer); \ |
| __ret; \ |
| }) |
| |
| /** |
| * wait_event_hrtimeout - sleep until a condition gets true or a timeout elapses |
| * @wq_head: the waitqueue to wait on |
| * @condition: a C expression for the event to wait for |
| * @timeout: timeout, as a ktime_t |
| * |
| * The process is put to sleep (TASK_UNINTERRUPTIBLE) until the |
| * @condition evaluates to true or a signal is received. |
| * The @condition is checked each time the waitqueue @wq_head 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 @condition became true, or -ETIME if the timeout |
| * elapsed. |
| */ |
| #define wait_event_hrtimeout(wq_head, condition, timeout) \ |
| ({ \ |
| int __ret = 0; \ |
| might_sleep(); \ |
| if (!(condition)) \ |
| __ret = __wait_event_hrtimeout(wq_head, condition, timeout, \ |
| TASK_UNINTERRUPTIBLE); \ |
| __ret; \ |
| }) |
| |
| /** |
| * wait_event_interruptible_hrtimeout - 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, as a ktime_t |
| * |
| * 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 @condition became true, -ERESTARTSYS if it was |
| * interrupted by a signal, or -ETIME if the timeout elapsed. |
| */ |
| #define wait_event_interruptible_hrtimeout(wq, condition, timeout) \ |
| ({ \ |
| long __ret = 0; \ |
| might_sleep(); \ |
| if (!(condition)) \ |
| __ret = __wait_event_hrtimeout(wq, condition, timeout, \ |
| TASK_INTERRUPTIBLE); \ |
| __ret; \ |
| }) |
| |
| #define __wait_event_interruptible_exclusive(wq, condition) \ |
| ___wait_event(wq, condition, TASK_INTERRUPTIBLE, 1, 0, \ |
| schedule()) |
| |
| #define wait_event_interruptible_exclusive(wq, condition) \ |
| ({ \ |
| int __ret = 0; \ |
| might_sleep(); \ |
| if (!(condition)) \ |
| __ret = __wait_event_interruptible_exclusive(wq, condition); \ |
| __ret; \ |
| }) |
| |
| #define __wait_event_killable_exclusive(wq, condition) \ |
| ___wait_event(wq, condition, TASK_KILLABLE, 1, 0, \ |
| schedule()) |
| |
| #define wait_event_killable_exclusive(wq, condition) \ |
| ({ \ |
| int __ret = 0; \ |
| might_sleep(); \ |
| if (!(condition)) \ |
| __ret = __wait_event_killable_exclusive(wq, condition); \ |
| __ret; \ |
| }) |
| |
| |
| #define __wait_event_freezable_exclusive(wq, condition) \ |
| ___wait_event(wq, condition, TASK_INTERRUPTIBLE, 1, 0, \ |
| freezable_schedule()) |
| |
| #define wait_event_freezable_exclusive(wq, condition) \ |
| ({ \ |
| int __ret = 0; \ |
| might_sleep(); \ |
| if (!(condition)) \ |
| __ret = __wait_event_freezable_exclusive(wq, condition); \ |
| __ret; \ |
| }) |
| |
| /** |
| * wait_event_idle - wait for a condition without contributing to system load |
| * @wq_head: the waitqueue to wait on |
| * @condition: a C expression for the event to wait for |
| * |
| * The process is put to sleep (TASK_IDLE) until the |
| * @condition evaluates to true. |
| * The @condition is checked each time the waitqueue @wq_head 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_idle(wq_head, condition) \ |
| do { \ |
| might_sleep(); \ |
| if (!(condition)) \ |
| ___wait_event(wq_head, condition, TASK_IDLE, 0, 0, schedule()); \ |
| } while (0) |
| |
| /** |
| * wait_event_idle_exclusive - wait for a condition with contributing to system load |
| * @wq_head: the waitqueue to wait on |
| * @condition: a C expression for the event to wait for |
| * |
| * The process is put to sleep (TASK_IDLE) until the |
| * @condition evaluates to true. |
| * The @condition is checked each time the waitqueue @wq_head is woken up. |
| * |
| * The process is put on the wait queue with an WQ_FLAG_EXCLUSIVE flag |
| * set thus if other processes wait on the same list, when this |
| * process is woken further processes are not considered. |
| * |
| * wake_up() has to be called after changing any variable that could |
| * change the result of the wait condition. |
| * |
| */ |
| #define wait_event_idle_exclusive(wq_head, condition) \ |
| do { \ |
| might_sleep(); \ |
| if (!(condition)) \ |
| ___wait_event(wq_head, condition, TASK_IDLE, 1, 0, schedule()); \ |
| } while (0) |
| |
| #define __wait_event_idle_timeout(wq_head, condition, timeout) \ |
| ___wait_event(wq_head, ___wait_cond_timeout(condition), \ |
| TASK_IDLE, 0, timeout, \ |
| __ret = schedule_timeout(__ret)) |
| |
| /** |
| * wait_event_idle_timeout - sleep without load until a condition becomes true or a timeout elapses |
| * @wq_head: 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_IDLE) until the |
| * @condition evaluates to true. The @condition is checked each time |
| * the waitqueue @wq_head is woken up. |
| * |
| * wake_up() has to be called after changing any variable that could |
| * change the result of the wait condition. |
| * |
| * Returns: |
| * 0 if the @condition evaluated to %false after the @timeout elapsed, |
| * 1 if the @condition evaluated to %true after the @timeout elapsed, |
| * or the remaining jiffies (at least 1) if the @condition evaluated |
| * to %true before the @timeout elapsed. |
| */ |
| #define wait_event_idle_timeout(wq_head, condition, timeout) \ |
| ({ \ |
| long __ret = timeout; \ |
| might_sleep(); \ |
| if (!___wait_cond_timeout(condition)) \ |
| __ret = __wait_event_idle_timeout(wq_head, condition, timeout); \ |
| __ret; \ |
| }) |
| |
| #define __wait_event_idle_exclusive_timeout(wq_head, condition, timeout) \ |
| ___wait_event(wq_head, ___wait_cond_timeout(condition), \ |
| TASK_IDLE, 1, timeout, \ |
| __ret = schedule_timeout(__ret)) |
| |
| /** |
| * wait_event_idle_exclusive_timeout - sleep without load until a condition becomes true or a timeout elapses |
| * @wq_head: 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_IDLE) until the |
| * @condition evaluates to true. The @condition is checked each time |
| * the waitqueue @wq_head is woken up. |
| * |
| * The process is put on the wait queue with an WQ_FLAG_EXCLUSIVE flag |
| * set thus if other processes wait on the same list, when this |
| * process is woken further processes are not considered. |
| * |
| * wake_up() has to be called after changing any variable that could |
| * change the result of the wait condition. |
| * |
| * Returns: |
| * 0 if the @condition evaluated to %false after the @timeout elapsed, |
| * 1 if the @condition evaluated to %true after the @timeout elapsed, |
| * or the remaining jiffies (at least 1) if the @condition evaluated |
| * to %true before the @timeout elapsed. |
| */ |
| #define wait_event_idle_exclusive_timeout(wq_head, condition, timeout) \ |
| ({ \ |
| long __ret = timeout; \ |
| might_sleep(); \ |
| if (!___wait_cond_timeout(condition)) \ |
| __ret = __wait_event_idle_exclusive_timeout(wq_head, condition, timeout);\ |
| __ret; \ |
| }) |
| |
| extern int do_wait_intr(wait_queue_head_t *, wait_queue_entry_t *); |
| extern int do_wait_intr_irq(wait_queue_head_t *, wait_queue_entry_t *); |
| |
| #define __wait_event_interruptible_locked(wq, condition, exclusive, fn) \ |
| ({ \ |
| int __ret; \ |
| DEFINE_WAIT(__wait); \ |
| if (exclusive) \ |
| __wait.flags |= WQ_FLAG_EXCLUSIVE; \ |
| do { \ |
| __ret = fn(&(wq), &__wait); \ |
| if (__ret) \ |
| break; \ |
| } while (!(condition)); \ |
| __remove_wait_queue(&(wq), &__wait); \ |
| __set_current_state(TASK_RUNNING); \ |
| __ret; \ |
| }) |
| |
| |
| /** |
| * wait_event_interruptible_locked - 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. |
| * |
| * It must be called with wq.lock being held. This spinlock is |
| * unlocked while sleeping but @condition testing is done while lock |
| * is held and when this macro exits the lock is held. |
| * |
| * The lock is locked/unlocked using spin_lock()/spin_unlock() |
| * functions which must match the way they are locked/unlocked outside |
| * of this macro. |
| * |
| * wake_up_locked() 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_locked(wq, condition) \ |
| ((condition) \ |
| ? 0 : __wait_event_interruptible_locked(wq, condition, 0, do_wait_intr)) |
| |
| /** |
| * wait_event_interruptible_locked_irq - 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. |
| * |
| * It must be called with wq.lock being held. This spinlock is |
| * unlocked while sleeping but @condition testing is done while lock |
| * is held and when this macro exits the lock is held. |
| * |
| * The lock is locked/unlocked using spin_lock_irq()/spin_unlock_irq() |
| * functions which must match the way they are locked/unlocked outside |
| * of this macro. |
| * |
| * wake_up_locked() 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_locked_irq(wq, condition) \ |
| ((condition) \ |
| ? 0 : __wait_event_interruptible_locked(wq, condition, 0, do_wait_intr_irq)) |
| |
| /** |
| * wait_event_interruptible_exclusive_locked - sleep exclusively 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. |
| * |
| * It must be called with wq.lock being held. This spinlock is |
| * unlocked while sleeping but @condition testing is done while lock |
| * is held and when this macro exits the lock is held. |
| * |
| * The lock is locked/unlocked using spin_lock()/spin_unlock() |
| * functions which must match the way they are locked/unlocked outside |
| * of this macro. |
| * |
| * The process is put on the wait queue with an WQ_FLAG_EXCLUSIVE flag |
| * set thus when other process waits process on the list if this |
| * process is awaken further processes are not considered. |
| * |
| * wake_up_locked() 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_exclusive_locked(wq, condition) \ |
| ((condition) \ |
| ? 0 : __wait_event_interruptible_locked(wq, condition, 1, do_wait_intr)) |
| |
| /** |
| * wait_event_interruptible_exclusive_locked_irq - 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. |
| * |
| * It must be called with wq.lock being held. This spinlock is |
| * unlocked while sleeping but @condition testing is done while lock |
| * is held and when this macro exits the lock is held. |
| * |
| * The lock is locked/unlocked using spin_lock_irq()/spin_unlock_irq() |
| * functions which must match the way they are locked/unlocked outside |
| * of this macro. |
| * |
| * The process is put on the wait queue with an WQ_FLAG_EXCLUSIVE flag |
| * set thus when other process waits process on the list if this |
| * process is awaken further processes are not considered. |
| * |
| * wake_up_locked() 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_exclusive_locked_irq(wq, condition) \ |
| ((condition) \ |
| ? 0 : __wait_event_interruptible_locked(wq, condition, 1, do_wait_intr_irq)) |
| |
| |
| #define __wait_event_killable(wq, condition) \ |
| ___wait_event(wq, condition, TASK_KILLABLE, 0, 0, schedule()) |
| |
| /** |
| * wait_event_killable - sleep until a condition gets true |
| * @wq_head: the waitqueue to wait on |
| * @condition: a C expression for the event to wait for |
| * |
| * The process is put to sleep (TASK_KILLABLE) until the |
| * @condition evaluates to true or a signal is received. |
| * The @condition is checked each time the waitqueue @wq_head 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_killable(wq_head, condition) \ |
| ({ \ |
| int __ret = 0; \ |
| might_sleep(); \ |
| if (!(condition)) \ |
| __ret = __wait_event_killable(wq_head, condition); \ |
| __ret; \ |
| }) |
| |
| #define __wait_event_killable_timeout(wq_head, condition, timeout) \ |
| ___wait_event(wq_head, ___wait_cond_timeout(condition), \ |
| TASK_KILLABLE, 0, timeout, \ |
| __ret = schedule_timeout(__ret)) |
| |
| /** |
| * wait_event_killable_timeout - sleep until a condition gets true or a timeout elapses |
| * @wq_head: 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_KILLABLE) until the |
| * @condition evaluates to true or a kill signal is received. |
| * The @condition is checked each time the waitqueue @wq_head is woken up. |
| * |
| * wake_up() has to be called after changing any variable that could |
| * change the result of the wait condition. |
| * |
| * Returns: |
| * 0 if the @condition evaluated to %false after the @timeout elapsed, |
| * 1 if the @condition evaluated to %true after the @timeout elapsed, |
| * the remaining jiffies (at least 1) if the @condition evaluated |
| * to %true before the @timeout elapsed, or -%ERESTARTSYS if it was |
| * interrupted by a kill signal. |
| * |
| * Only kill signals interrupt this process. |
| */ |
| #define wait_event_killable_timeout(wq_head, condition, timeout) \ |
| ({ \ |
| long __ret = timeout; \ |
| might_sleep(); \ |
| if (!___wait_cond_timeout(condition)) \ |
| __ret = __wait_event_killable_timeout(wq_head, \ |
| condition, timeout); \ |
| __ret; \ |
| }) |
| |
| |
| #define __wait_event_lock_irq(wq_head, condition, lock, cmd) \ |
| (void)___wait_event(wq_head, condition, TASK_UNINTERRUPTIBLE, 0, 0, \ |
| spin_unlock_irq(&lock); \ |
| cmd; \ |
| schedule(); \ |
| spin_lock_irq(&lock)) |
| |
| /** |
| * wait_event_lock_irq_cmd - sleep until a condition gets true. The |
| * condition is checked under the lock. This |
| * is expected to be called with the lock |
| * taken. |
| * @wq_head: the waitqueue to wait on |
| * @condition: a C expression for the event to wait for |
| * @lock: a locked spinlock_t, which will be released before cmd |
| * and schedule() and reacquired afterwards. |
| * @cmd: a command which is invoked outside the critical section before |
| * sleep |
| * |
| * The process is put to sleep (TASK_UNINTERRUPTIBLE) until the |
| * @condition evaluates to true. The @condition is checked each time |
| * the waitqueue @wq_head is woken up. |
| * |
| * wake_up() has to be called after changing any variable that could |
| * change the result of the wait condition. |
| * |
| * This is supposed to be called while holding the lock. The lock is |
| * dropped before invoking the cmd and going to sleep and is reacquired |
| * afterwards. |
| */ |
| #define wait_event_lock_irq_cmd(wq_head, condition, lock, cmd) \ |
| do { \ |
| if (condition) \ |
| break; \ |
| __wait_event_lock_irq(wq_head, condition, lock, cmd); \ |
| } while (0) |
| |
| /** |
| * wait_event_lock_irq - sleep until a condition gets true. The |
| * condition is checked under the lock. This |
| * is expected to be called with the lock |
| * taken. |
| * @wq_head: the waitqueue to wait on |
| * @condition: a C expression for the event to wait for |
| * @lock: a locked spinlock_t, which will be released before schedule() |
| * and reacquired afterwards. |
| * |
| * The process is put to sleep (TASK_UNINTERRUPTIBLE) until the |
| * @condition evaluates to true. The @condition is checked each time |
| * the waitqueue @wq_head is woken up. |
| * |
| * wake_up() has to be called after changing any variable that could |
| * change the result of the wait condition. |
| * |
| * This is supposed to be called while holding the lock. The lock is |
| * dropped before going to sleep and is reacquired afterwards. |
| */ |
| #define wait_event_lock_irq(wq_head, condition, lock) \ |
| do { \ |
| if (condition) \ |
| break; \ |
| __wait_event_lock_irq(wq_head, condition, lock, ); \ |
| } while (0) |
| |
| |
| #define __wait_event_interruptible_lock_irq(wq_head, condition, lock, cmd) \ |
| ___wait_event(wq_head, condition, TASK_INTERRUPTIBLE, 0, 0, \ |
| spin_unlock_irq(&lock); \ |
| cmd; \ |
| schedule(); \ |
| spin_lock_irq(&lock)) |
| |
| /** |
| * wait_event_interruptible_lock_irq_cmd - sleep until a condition gets true. |
| * The condition is checked under the lock. This is expected to |
| * be called with the lock taken. |
| * @wq_head: the waitqueue to wait on |
| * @condition: a C expression for the event to wait for |
| * @lock: a locked spinlock_t, which will be released before cmd and |
| * schedule() and reacquired afterwards. |
| * @cmd: a command which is invoked outside the critical section before |
| * sleep |
| * |
| * 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_head is woken up. |
| * |
| * wake_up() has to be called after changing any variable that could |
| * change the result of the wait condition. |
| * |
| * This is supposed to be called while holding the lock. The lock is |
| * dropped before invoking the cmd and going to sleep and is reacquired |
| * afterwards. |
| * |
| * The macro will return -ERESTARTSYS if it was interrupted by a signal |
| * and 0 if @condition evaluated to true. |
| */ |
| #define wait_event_interruptible_lock_irq_cmd(wq_head, condition, lock, cmd) \ |
| ({ \ |
| int __ret = 0; \ |
| if (!(condition)) \ |
| __ret = __wait_event_interruptible_lock_irq(wq_head, \ |
| condition, lock, cmd); \ |
| __ret; \ |
| }) |
| |
| /** |
| * wait_event_interruptible_lock_irq - sleep until a condition gets true. |
| * The condition is checked under the lock. This is expected |
| * to be called with the lock taken. |
| * @wq_head: the waitqueue to wait on |
| * @condition: a C expression for the event to wait for |
| * @lock: a locked spinlock_t, which will be released before schedule() |
| * and reacquired afterwards. |
| * |
| * The process is put to sleep (TASK_INTERRUPTIBLE) until the |
| * @condition evaluates to true or signal is received. The @condition is |
| * checked each time the waitqueue @wq_head is woken up. |
| * |
| * wake_up() has to be called after changing any variable that could |
| * change the result of the wait condition. |
| * |
| * This is supposed to be called while holding the lock. The lock is |
| * dropped before going to sleep and is reacquired afterwards. |
| * |
| * The macro will return -ERESTARTSYS if it was interrupted by a signal |
| * and 0 if @condition evaluated to true. |
| */ |
| #define wait_event_interruptible_lock_irq(wq_head, condition, lock) \ |
| ({ \ |
| int __ret = 0; \ |
| if (!(condition)) \ |
| __ret = __wait_event_interruptible_lock_irq(wq_head, \ |
| condition, lock,); \ |
| __ret; \ |
| }) |
| |
| #define __wait_event_lock_irq_timeout(wq_head, condition, lock, timeout, state) \ |
| ___wait_event(wq_head, ___wait_cond_timeout(condition), \ |
| state, 0, timeout, \ |
| spin_unlock_irq(&lock); \ |
| __ret = schedule_timeout(__ret); \ |
| spin_lock_irq(&lock)); |
| |
| /** |
| * wait_event_interruptible_lock_irq_timeout - sleep until a condition gets |
| * true or a timeout elapses. The condition is checked under |
| * the lock. This is expected to be called with the lock taken. |
| * @wq_head: the waitqueue to wait on |
| * @condition: a C expression for the event to wait for |
| * @lock: a locked spinlock_t, which will be released before schedule() |
| * and reacquired afterwards. |
| * @timeout: timeout, in jiffies |
| * |
| * The process is put to sleep (TASK_INTERRUPTIBLE) until the |
| * @condition evaluates to true or signal is received. The @condition is |
| * checked each time the waitqueue @wq_head is woken up. |
| * |
| * wake_up() has to be called after changing any variable that could |
| * change the result of the wait condition. |
| * |
| * This is supposed to be called while holding the lock. The lock is |
| * dropped before going to sleep and is reacquired afterwards. |
| * |
| * 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_lock_irq_timeout(wq_head, condition, lock, \ |
| timeout) \ |
| ({ \ |
| long __ret = timeout; \ |
| if (!___wait_cond_timeout(condition)) \ |
| __ret = __wait_event_lock_irq_timeout( \ |
| wq_head, condition, lock, timeout, \ |
| TASK_INTERRUPTIBLE); \ |
| __ret; \ |
| }) |
| |
| #define wait_event_lock_irq_timeout(wq_head, condition, lock, timeout) \ |
| ({ \ |
| long __ret = timeout; \ |
| if (!___wait_cond_timeout(condition)) \ |
| __ret = __wait_event_lock_irq_timeout( \ |
| wq_head, condition, lock, timeout, \ |
| TASK_UNINTERRUPTIBLE); \ |
| __ret; \ |
| }) |
| |
| /* |
| * Waitqueues which are removed from the waitqueue_head at wakeup time |
| */ |
| void prepare_to_wait(struct wait_queue_head *wq_head, struct wait_queue_entry *wq_entry, int state); |
| void prepare_to_wait_exclusive(struct wait_queue_head *wq_head, struct wait_queue_entry *wq_entry, int state); |
| long prepare_to_wait_event(struct wait_queue_head *wq_head, struct wait_queue_entry *wq_entry, int state); |
| void finish_wait(struct wait_queue_head *wq_head, struct wait_queue_entry *wq_entry); |
| long wait_woken(struct wait_queue_entry *wq_entry, unsigned mode, long timeout); |
| int woken_wake_function(struct wait_queue_entry *wq_entry, unsigned mode, int sync, void *key); |
| int autoremove_wake_function(struct wait_queue_entry *wq_entry, unsigned mode, int sync, void *key); |
| |
| #define DEFINE_WAIT_FUNC(name, function) \ |
| struct wait_queue_entry name = { \ |
| .private = current, \ |
| .func = function, \ |
| .entry = LIST_HEAD_INIT((name).entry), \ |
| } |
| |
| #define DEFINE_WAIT(name) DEFINE_WAIT_FUNC(name, autoremove_wake_function) |
| |
| #define init_wait(wait) \ |
| do { \ |
| (wait)->private = current; \ |
| (wait)->func = autoremove_wake_function; \ |
| INIT_LIST_HEAD(&(wait)->entry); \ |
| (wait)->flags = 0; \ |
| } while (0) |
| |
| bool try_invoke_on_locked_down_task(struct task_struct *p, bool (*func)(struct task_struct *t, void *arg), void *arg); |
| |
| #endif /* _LINUX_WAIT_H */ |