bigfanofloT 发表于 2017-11-25 12:40:13

【一起来玩RTOS系列】之RT-Thread 线程的挂起和恢复

线程挂起

当线程调用rt_thread_delay,调用线程将主动挂起,当调用rt_sem_take,rt_mb_recv等函数时,资源不可使用也将导致调用线程挂起。处于挂起状态的线程,如果其等待的资源超时(超过其设定的等待时间),那么该线程将不再等待这些资源,并返回到就绪状态;或者,当其它线程释放掉该线程所等待的资源时,该线程也会返回到就绪状态。
线程挂起使用下面的函数接口:
rt_err_t rt_thread_suspend (rt_thread_t thread);线程安全:安全
中断例程:可调用
函数参数
thread线程句柄。
函数返回
如果这个线程的状态并不是就绪状态,将返回-RT_ERROR,否则返回RT_EOK
注:通常不应该使用这个函数来挂起线程本身,如果确实需要采用rt_thread_suspend函数挂起当前任务,需要在调用rt_thread_suspend()函数后立刻调用rt_schedule()函数进行手动的线程上下文切换。

线程恢复

线程恢复就是让挂起的线程重新进入就绪状态,如果被恢复线程在所有就绪态线程中,位于最高优先级链表的第一位,那么系统将进行线程上下文的切换。线程恢复使用下面的函数接口:
    rt_err_t rt_thread_resume (rt_thread_t thread);线程安全:安全
中断例程:可调用
函数参数
thread要恢复的线程句柄。
函数返回
如果恢复的线程状态并不是RT_THREAD_SUSPEND状态,将返回-RT_ERROR;否则返回RT_EOK。

下面在机智云Gokit开发板上演示线程的创建和恢复过程,程序中创建了2个不同优先级的线程,高优先级线程启动后立即阻塞,让出处理器,低优先级的线程启动后挂起自身等待高优先级线程的唤醒,通过串口可以查看打印信息。
/**
****************************************************
* File Name          : main.c
* Description      : Main program body
****************************************************
** This notice applies to any and all portions of this file
* that are not between comment pairs USER CODE BEGIN and
* USER CODE END. Other portions of this file, whether
* inserted by the user or by software development tools
* are owned by their respective copyright owners.
*
* COPYRIGHT(c) 2017 STMicroelectronics
*
* Redistribution and use in source and binary forms, with or without modification,
* are permitted provided that the following conditions are met:
*   1. Redistributions of source code must retain the above copyright notice,
*      this list of conditions and the following disclaimer.
*   2. Redistributions in binary form must reproduce the above copyright notice,
*      this list of conditions and the following disclaimer in the documentation
*      and/or other materials provided with the distribution.
*   3. Neither the name of STMicroelectronics nor the names of its contributors
*      may be used to endorse or promote products derived from this software
*      without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
****************************************************
*/
/* Includes ------------------------------------------------------------------*/
#include "main.h"
#include "stm32f1xx_hal.h"
#include "usart.h"
#include "gpio.h"

/* USER CODE BEGIN Includes */
#include "rtthread.h"
/* USER CODE END Includes */

/* Private variables ---------------------------------------------------------*/

/* USER CODE BEGIN PV */
/* Private variables ---------------------------------------------------------*/

/* USER CODE END PV */

/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);

/* USER CODE BEGIN PFP */
/* Private function prototypes -----------------------------------------------*/

/* USER CODE END PFP */

/* USER CODE BEGIN 0 */
//重映射串口1到rt_kprintf
void rt_hw_console_output(const char *str)
{
    /* empty console output */
        char aa='\r';
          rt_enter_critical();

                while(*str!='\0')
                {
                        if(*str=='\n')
                        {
                                HAL_UART_Transmit(&huart1, (uint8_t *)&aa, 1, 10);
                        }
                                HAL_UART_Transmit(&huart1, (uint8_t *)(str++), 1, 10);
                }
               
                rt_exit_critical();
}


/*
* 程序清单:线程的挂起和恢复
* 这个例子中将创建两个动态线程(tid1和tid2),
* 低优先级线程t1将挂起自身
* 高优先级线程t2将在一定时刻后唤醒低优先级线程。
*/

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

/* 线程1入口 */
static void thread1_entry(void* parameter)
{
        /* 低优先级线程1开始运行 */
        rt_kprintf("thread1 startup\n");
        /* 挂起自身 */
        rt_kprintf("thread1 suspend thread self\n");
        rt_thread_suspend(tid1);
        /* 主动执行线程调度 */
        rt_schedule();
        /* 当线程1被唤醒时 */
        rt_kprintf("thread1 resumed\n");
}

/* 线程2入口 */
static void thread2_entry(void* parameter)
{
        /* 延时1000个OS Tick */
        rt_thread_delay(1000);
        /* 唤醒线程1 */
        rt_thread_resume(tid1);
        /* 延时1000个OS Tick */
        rt_thread_delay(1000);
        /* 线程2自动退出 */
}

/* USER CODE END 0 */

int main(void)
{

/* USER CODE BEGIN 1 */

/* USER CODE END 1 */

/* MCU Configuration----------------------------------------------------------*/

///* Reset of all peripherals, Initializes the Flash interface and the Systick. */
//HAL_Init();

///* USER CODE BEGIN Init */

///* USER CODE END Init */

///* Configure the system clock */
//SystemClock_Config();

///* USER CODE BEGIN SysInit */

///* USER CODE END SysInit */

///* Initialize all configured peripherals */
//MX_GPIO_Init();
//MX_USART1_UART_Init();

/* USER CODE BEGIN 2 */
       
   /* 创建线程1 */
    tid1 = rt_thread_create("t1",
                                                        thread1_entry,
                                                        RT_NULL,
                                                        512,
                                                        2,
                                                        20);
        if (tid1 != RT_NULL)
                rt_thread_startup(tid1);
       
        /* 创建线程2 */
        tid2 = rt_thread_create("t2",
                                                        thread2_entry,
                                                        RT_NULL,
                                                        512,
                                                        1,
                                                        20);

        if (tid2 != RT_NULL)
                rt_thread_startup(tid2);
       
        printf("\r\n机智云只为智能硬件而生\r\n");
        printf("Gizwits Smart Cloud for Smart Products\r\n");
        printf("链接|增值|开放|中立|安全|自有|自由|生态\r\n");
        printf("www.gizwits.com\r\n");
        printf("\r\nGokit RT-Thread Demo\r\n\r\n");
       
        return 0;
       
       


/* USER CODE END 2 */

/* Infinite loop */
/* USER CODE BEGIN WHILE */
//while (1)
//{
/* USER CODE END WHILE */

/* USER CODE BEGIN 3 */
//               
//}
/* USER CODE END 3 */

}

/** System Clock Configuration
*/
void SystemClock_Config(void)
{

RCC_OscInitTypeDef RCC_OscInitStruct;
RCC_ClkInitTypeDef RCC_ClkInitStruct;

    /**Initializes the CPU, AHB and APB busses clocks
    */
RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSE;
RCC_OscInitStruct.HSEState = RCC_HSE_ON;
RCC_OscInitStruct.HSEPredivValue = RCC_HSE_PREDIV_DIV1;
RCC_OscInitStruct.HSIState = RCC_HSI_ON;
RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;
RCC_OscInitStruct.PLL.PLLMUL = RCC_PLL_MUL9;
if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
{
    _Error_Handler(__FILE__, __LINE__);
}

    /**Initializes the CPU, AHB and APB busses clocks
    */
RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK
                              |RCC_CLOCKTYPE_PCLK1|RCC_CLOCKTYPE_PCLK2;
RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV2;
RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;

if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_2) != HAL_OK)
{
    _Error_Handler(__FILE__, __LINE__);
}

    /**Configure the Systick interrupt time
    */
HAL_SYSTICK_Config(HAL_RCC_GetHCLKFreq()/1000);

    /**Configure the Systick
    */
HAL_SYSTICK_CLKSourceConfig(SYSTICK_CLKSOURCE_HCLK);

/* SysTick_IRQn interrupt configuration */
HAL_NVIC_SetPriority(SysTick_IRQn, 0, 0);
}

/* USER CODE BEGIN 4 */

/* USER CODE END 4 */

/**
* @briefThis function is executed in case of error occurrence.
* @paramNone
* @retval None
*/
void _Error_Handler(char * file, int line)
{
/* USER CODE BEGIN Error_Handler_Debug */
/* User can add his own implementation to report the HAL error return state */
while(1)
{
}
/* USER CODE END Error_Handler_Debug */
}

#ifdef USE_FULL_ASSERT

/**
   * @brief Reports the name of the source file and the source line number
   * where the assert_param error has occurred.
   * @param file: pointer to the source file name
   * @param line: assert_param error line source number
   * @retval None
   */
void assert_failed(uint8_t* file, uint32_t line)
{
/* USER CODE BEGIN 6 */
/* User can add his own implementation to report the file name and line number,
    ex: printf("Wrong parameters value: file %s on line %d\r\n", file, line) */
/* USER CODE END 6 */

}

#endif

/**
* @}
*/

/**
* @}
*/

/**************** (C) COPYRIGHT STMicroelectronics ****END OF FILE***/

通过串口看到打印信息与预期一致:



源码工程下载:




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