/* * Copyright (c) 2006-2021, RT-Thread Development Team * * SPDX-License-Identifier: Apache-2.0 * * Change Logs: * Date Author Notes * 2018/06/26 Bernard Fix the wait queue issue when wakeup a soon * to blocked thread. * 2022-01-24 THEWON let rt_wqueue_wait return thread->error when using signal */ #include #include #include #include /** * @brief This function will insert a node to the wait queue. * * @param queue is a pointer to the wait queue. * * @param node is a pointer to the node to be inserted. */ void rt_wqueue_add(rt_wqueue_t *queue, struct rt_wqueue_node *node) { rt_base_t level; level = rt_hw_interrupt_disable(); rt_list_insert_before(&(queue->waiting_list), &(node->list)); rt_hw_interrupt_enable(level); } /** * @brief This function will remove a node from the wait queue. * * @param node is a pointer to the node to be removed. */ void rt_wqueue_remove(struct rt_wqueue_node *node) { rt_base_t level; level = rt_hw_interrupt_disable(); rt_list_remove(&(node->list)); rt_hw_interrupt_enable(level); } /** * @brief This function is the default wakeup function, but it doesn't do anything in actual. * It always return 0, user should define their own wakeup function. * * @param wait is a pointer to the wait queue. * * @param key is the wakeup condition. * * @return always return 0. */ int __wqueue_default_wake(struct rt_wqueue_node *wait, void *key) { return 0; } /** * @brief This function will wake up a pending thread on the specified waiting queue that meets the conditions. * * @param queue is a pointer to the wait queue. * * @param key is the wakeup conditions, but it is not effective now, because * default wakeup function always return 0. * If user wants to use it, user should define their own wakeup function. */ void rt_wqueue_wakeup(rt_wqueue_t *queue, void *key) { rt_base_t level; int need_schedule = 0; rt_list_t *queue_list; struct rt_list_node *node; struct rt_wqueue_node *entry; queue_list = &(queue->waiting_list); level = rt_hw_interrupt_disable(); /* set wakeup flag in the queue */ queue->flag = RT_WQ_FLAG_WAKEUP; if (!(rt_list_isempty(queue_list))) { for (node = queue_list->next; node != queue_list; node = node->next) { entry = rt_list_entry(node, struct rt_wqueue_node, list); if (entry->wakeup(entry, key) == 0) { rt_thread_resume(entry->polling_thread); need_schedule = 1; rt_wqueue_remove(entry); break; } } } rt_hw_interrupt_enable(level); if (need_schedule) rt_schedule(); } /** * @brief This function will join a thread to the specified waiting queue, the thread will holds a wait or * timeout return on the specified wait queue. * * @param queue is a pointer to the wait queue. * * @param condition is parameters compatible with POSIX standard interface (currently meaningless, just pass in 0). * * @param msec is the timeout value, unit is millisecond. * * @return Return 0 if the thread is woken up. */ static int _rt_wqueue_wait(rt_wqueue_t *queue, int condition, int msec, int suspend_flag) { int tick; rt_thread_t tid = rt_thread_self(); rt_timer_t tmr = &(tid->thread_timer); struct rt_wqueue_node __wait; rt_base_t level; rt_err_t ret; /* current context checking */ RT_DEBUG_SCHEDULER_AVAILABLE(RT_TRUE); tick = rt_tick_from_millisecond(msec); if ((condition) || (tick == 0)) return 0; __wait.polling_thread = rt_thread_self(); __wait.key = 0; __wait.wakeup = __wqueue_default_wake; rt_list_init(&__wait.list); level = rt_hw_interrupt_disable(); /* reset thread error */ tid->error = RT_EOK; if (queue->flag == RT_WQ_FLAG_WAKEUP) { /* already wakeup */ goto __exit_wakeup; } ret = rt_thread_suspend_with_flag(tid, suspend_flag); if (ret != RT_EOK) { rt_hw_interrupt_enable(level); /* suspend failed */ return -RT_EINTR; } rt_wqueue_add(queue, &__wait); /* start timer */ if (tick != RT_WAITING_FOREVER) { rt_timer_control(tmr, RT_TIMER_CTRL_SET_TIME, &tick); rt_timer_start(tmr); } rt_hw_interrupt_enable(level); rt_schedule(); level = rt_hw_interrupt_disable(); __exit_wakeup: queue->flag = RT_WQ_FLAG_CLEAN; rt_hw_interrupt_enable(level); rt_wqueue_remove(&__wait); return tid->error; } int rt_wqueue_wait(rt_wqueue_t *queue, int condition, int msec) { return _rt_wqueue_wait(queue, condition, msec, RT_UNINTERRUPTIBLE); } int rt_wqueue_wait_killable(rt_wqueue_t *queue, int condition, int msec) { return _rt_wqueue_wait(queue, condition, msec, RT_KILLABLE); } int rt_wqueue_wait_interruptible(rt_wqueue_t *queue, int condition, int msec) { return _rt_wqueue_wait(queue, condition, msec, RT_INTERRUPTIBLE); }