rt-thread-official/components/drivers/ipc/completion.c

162 lines
4.6 KiB
C

/*
* Copyright (c) 2006-2021, RT-Thread Development Team
*
* SPDX-License-Identifier: Apache-2.0
*
* Change Logs:
* Date Author Notes
* 2012-09-30 Bernard first version.
* 2021-08-18 chenyingchun add comments
*/
#include <rthw.h>
#include <rtthread.h>
#include <rtdevice.h>
#define RT_COMPLETED 1
#define RT_UNCOMPLETED 0
/**
* @brief This function will initialize a completion object.
*
* @param completion is a pointer to a completion object.
*/
void rt_completion_init(struct rt_completion *completion)
{
rt_base_t level;
RT_ASSERT(completion != RT_NULL);
level = rt_hw_interrupt_disable();
completion->flag = RT_UNCOMPLETED;
rt_list_init(&completion->suspended_list);
rt_hw_interrupt_enable(level);
}
RTM_EXPORT(rt_completion_init);
/**
* @brief This function will wait for a completion, if the completion is unavailable, the thread shall wait for
* the completion up to a specified time.
*
* @param completion is a pointer to a completion object.
*
* @param timeout is a timeout period (unit: OS ticks). If the completion is unavailable, the thread will wait for
* the completion done up to the amount of time specified by the argument.
* NOTE: Generally, we use the macro RT_WAITING_FOREVER to set this parameter, which means that when the
* completion is unavailable, the thread will be waitting forever.
*
* @return Return the operation status. ONLY when the return value is RT_EOK, the operation is successful.
* If the return value is any other values, it means that the completion wait failed.
*
* @warning This function can ONLY be called in the thread context. It MUST NOT be called in interrupt context.
*/
rt_err_t rt_completion_wait(struct rt_completion *completion,
rt_int32_t timeout)
{
rt_err_t result;
rt_base_t level;
rt_thread_t thread;
RT_ASSERT(completion != RT_NULL);
/* current context checking */
RT_DEBUG_SCHEDULER_AVAILABLE(timeout != 0);
result = RT_EOK;
thread = rt_thread_self();
level = rt_hw_interrupt_disable();
if (completion->flag != RT_COMPLETED)
{
/* only one thread can suspend on complete */
RT_ASSERT(rt_list_isempty(&(completion->suspended_list)));
if (timeout == 0)
{
result = -RT_ETIMEOUT;
goto __exit;
}
else
{
/* reset thread error number */
thread->error = RT_EOK;
/* suspend thread */
rt_thread_suspend_with_flag(thread, RT_UNINTERRUPTIBLE);
/* add to suspended list */
rt_list_insert_before(&(completion->suspended_list),
&(thread->tlist));
/* current context checking */
RT_DEBUG_NOT_IN_INTERRUPT;
/* start timer */
if (timeout > 0)
{
/* reset the timeout of thread timer and start it */
rt_timer_control(&(thread->thread_timer),
RT_TIMER_CTRL_SET_TIME,
&timeout);
rt_timer_start(&(thread->thread_timer));
}
/* enable interrupt */
rt_hw_interrupt_enable(level);
/* do schedule */
rt_schedule();
/* thread is waked up */
result = thread->error;
level = rt_hw_interrupt_disable();
}
}
/* clean completed flag */
completion->flag = RT_UNCOMPLETED;
__exit:
rt_hw_interrupt_enable(level);
return result;
}
RTM_EXPORT(rt_completion_wait);
/**
* @brief This function indicates a completion has done.
*
* @param completion is a pointer to a completion object.
*/
void rt_completion_done(struct rt_completion *completion)
{
rt_base_t level;
RT_ASSERT(completion != RT_NULL);
if (completion->flag == RT_COMPLETED)
return;
level = rt_hw_interrupt_disable();
completion->flag = RT_COMPLETED;
if (!rt_list_isempty(&(completion->suspended_list)))
{
/* there is one thread in suspended list */
struct rt_thread *thread;
/* get thread entry */
thread = rt_list_entry(completion->suspended_list.next,
struct rt_thread,
tlist);
/* resume it */
rt_thread_resume(thread);
rt_hw_interrupt_enable(level);
/* perform a schedule */
rt_schedule();
}
else
{
rt_hw_interrupt_enable(level);
}
}
RTM_EXPORT(rt_completion_done);