rt-thread-official/examples/kernel/mutex_simple.c

/*
 * 程序清单：
 */
#include <rtthread.h>
#include "tc_comm.h"

/* 指向线程控制块的指针 */
static rt_thread_t tid1 = RT_NULL;
static rt_thread_t tid2 = RT_NULL;
static rt_thread_t tid3 = RT_NULL;
static rt_mutex_t mutex = RT_NULL;

/* 线程1入口 */
static void thread1_entry(void* parameter)
{
	/* 先让低优先级线程运行 */
	rt_thread_delay(10);

	/* 此时thread3持有mutex，并且thread2等待持有mutex */

	/* 检查thread2与thread3的优先级情况 */
	if (tid2->current_priority != tid3->current_priority)
	{
		/* 优先级不相同，测试失败 */
		tc_stat(TC_STAT_END | TC_STAT_FAILED);
		return;
	}
}

/* 线程2入口 */
static void thread2_entry(void* parameter)
{
	rt_err_t result;

	/* 先让低优先级线程运行 */
	rt_thread_delay(5);

	while (1)
	{
		/*
		 * 试图持有互斥锁，此时thread3持有，应把thread3的优先级提升到thread2相同
		 * 的优先级
		 */
		result = rt_mutex_take(mutex, RT_WAITING_FOREVER);

		if (result == RT_EOK)
		{
			/* 释放互斥锁 */
			rt_mutex_release(mutex);
		}
	}
}

/* 线程3入口 */
static void thread3_entry(void* parameter)
{
	rt_tick_t tick;
	rt_err_t result;

	while (1)
	{
		result = rt_mutex_take(mutex, RT_WAITING_FOREVER);
		result = rt_mutex_take(mutex, RT_WAITING_FOREVER);
		if (result != RT_EOK)
		{
			tc_stat(TC_STAT_END | TC_STAT_FAILED);
		}

		/* 做一个长时间的循环，总共50个OS Tick */
		tick = rt_tick_get();
		while (rt_tick_get() - tick < 50) ;

		rt_mutex_release(mutex);
		rt_mutex_release(mutex);
	}
}

int mutex_simple_init()
{
	/* 创建互斥锁 */
	mutex = rt_mutex_create("mutex", RT_IPC_FLAG_FIFO);
	if (mutex == RT_NULL)
	{
		tc_stat(TC_STAT_END | TC_STAT_FAILED);
		return 0;
	}

	/* 创建线程1 */
	tid1 = rt_thread_create("t1",
		thread1_entry, RT_NULL, /* 线程入口是thread1_entry, 入口参数是RT_NULL */
		THREAD_STACK_SIZE, THREAD_PRIORITY - 1, THREAD_TIMESLICE);
	if (tid1 != RT_NULL)
		rt_thread_startup(tid1);
	else
		tc_stat(TC_STAT_END | TC_STAT_FAILED);

	/* 创建线程2 */
	tid2 = rt_thread_create("t2",
		thread2_entry, RT_NULL, /* 线程入口是thread2_entry, 入口参数是RT_NULL */
		THREAD_STACK_SIZE, THREAD_PRIORITY, THREAD_TIMESLICE);
	if (tid2 != RT_NULL)
		rt_thread_startup(tid2);
	else
		tc_stat(TC_STAT_END | TC_STAT_FAILED);

	/* 创建线程3 */
	tid3 = rt_thread_create("t3",
		thread3_entry, RT_NULL, /* 线程入口是thread3_entry, 入口参数是RT_NULL */
		THREAD_STACK_SIZE, THREAD_PRIORITY + 1, THREAD_TIMESLICE);
	if (tid3 != RT_NULL)
		rt_thread_startup(tid3);
	else
		tc_stat(TC_STAT_END | TC_STAT_FAILED);

	return 0;
}

#ifdef RT_USING_TC
static void _tc_cleanup()
{
	/* 调度器上锁，上锁后，将不再切换到其他线程，仅响应中断 */
	rt_enter_critical();

	/* 删除线程 */
	if (tid1 != RT_NULL && tid1->stat != RT_THREAD_CLOSE)
		rt_thread_delete(tid1);
	if (tid2 != RT_NULL && tid2->stat != RT_THREAD_CLOSE)
		rt_thread_delete(tid2);
	if (tid3 != RT_NULL && tid3->stat != RT_THREAD_CLOSE)
		rt_thread_delete(tid3);

	if (mutex != RT_NULL)
	{
		rt_mutex_delete(mutex);
	}

	/* 调度器解锁 */
	rt_exit_critical();

	/* 设置TestCase状态 */
	tc_done(TC_STAT_PASSED);
}

int _tc_mutex_simple()
{
	/* 设置TestCase清理回调函数 */
	tc_cleanup(_tc_cleanup);
	mutex_simple_init();

	/* 返回TestCase运行的最长时间 */
	return 100;
}
/* 输出函数命令到finsh shell中 */
FINSH_FUNCTION_EXPORT(_tc_mutex_simple, sime mutex example);
#else
/* 用户应用入口 */
int rt_application_init()
{
	mutex_simple_init();

	return 0;
}
#endif