RT-Thread-stm32h7 串口 dma 发送长时间运行似乎会卡死RT-Thread问答社区

10 stm32h7 串口 dma 发送长时间运行似乎会卡死

发布于 2025-04-28 09:02:26 浏览：54 订阅该版

最近在公司内部的一个使用了 stm32h743 的模块在长时间运行好几个小时过后，出现了奇怪的现象。原本正常定时外发协议数据的一个串口，突然不发送数据了。 结合调试打印，感觉似乎是发送线程在进入 `rt_device_write`的逻辑后, 就没有再次退出了。但 shell等其他正常的， shell 输入 ps 后的结果也挺奇怪的，居然有2个线程同时进入了 `RUNING` 的状态 (shell 和这个串口的发送线程)，这显然不正常。请问大家觉得可能是什么原因? 谢谢!

异常情况下的 ps 结果:

![screenshot_image.png](https://oss-club.rt-thread.org/uploads/20250428/efaf7941335cdd0f77b0c359fd81d0ad.png.webp)

与重新上电恢复后的正常情况对比:

![screenshot_image.png](https://oss-club.rt-thread.org/uploads/20250428/3ed4b1ecdee3f6778ca973655cc847c4.png.webp)

部分业务逻辑展示: 为了便于使用，我们公司的前辈封装了一个 Serial 类，用于异步发送串口数据，因为部分逻辑涉及公司内部协议，这里只展示了部分串口发送相关的逻辑：

```CXX
#include "rtthread.h"
#include "rtdevice.h"

#define LOG_TAG "app.serial"
#define LOG_LVL LOG_LVL_DBG
#include "ulog.h"

struct serial_app_config
{
    char usname[RT_NAME_MAX];
    int baudrate;

// .....
};

class Serial
{
public:
    Serial(struct serial_app_config serial_cfg);
    ~Serial();

bool StartTxProcess();
    void TxDone();

private:
    char _us_name[RT_NAME_MAX];

rt_device_t dev_serial;
    rt_ringbuffer Serial_Tx_ringbuffer;
    rt_uint8_t *_serial_tx_bufTransfer;
    rt_uint8_t *_serial_tx_buf;

rt_sem_t serial_tx_sem;
    rt_sem_t serial_txRing_sem;

bool SendData(rt_uint8_t *data, int len);
    rt_mutex_t dynamic_mutex = RT_NULL;

bool isread_exit;
};

void Serial::TxDone()
{   
    log_d("Tx Done %s", _us_name);
    rt_sem_release(serial_tx_sem);
}

bool Serial::SendData(rt_uint8_t  * data, int len) 
{
    bool result = false;

if(rt_mutex_take(dynamic_mutex, 10) == RT_EOK)
    {
        int buff_left =rt_ringbuffer_space_len(&Serial_Tx_ringbuffer);
        if(buff_left == 0  || len > buff_left)
        {
            rt_ringbuffer_reset(&Serial_Tx_ringbuffer);
            buff_left =rt_ringbuffer_space_len(&Serial_Tx_ringbuffer);
        }
        if(len > buff_left)
        {
            len = buff_left;
        }
        if(len <= buff_left)
        {
            int putlen = rt_ringbuffer_put(&Serial_Tx_ringbuffer,data,len);
            if(putlen != len)
            {
                rt_ringbuffer_reset(&Serial_Tx_ringbuffer);
            }
            else
            {
                result = true;
            }
            
        }
        rt_mutex_release(dynamic_mutex);
    }

if(result == true)
    {
        rt_sem_release(serial_txRing_sem);
    }

return result;
}

bool Serial::StartTxProcess()
{
    bool result = false;
    rt_uint16_t waitTime = 2000;
		
    while(!isread_exit)
    {
        rt_sem_take(serial_txRing_sem,waitTime);

if(rt_sem_take(serial_tx_sem,500) == RT_EOK)
        {
            result = rt_mutex_take(dynamic_mutex, 10);
            if(result == RT_EOK)
            {
                int len = rt_ringbuffer_cpy(&Serial_Tx_ringbuffer, _serial_tx_buf, len);
                rt_mutex_release(dynamic_mutex);

if(len > 0)
                {
                    // 发送疑似进入后就没有再退出。。。
                    rt_uint16_t len_write = rt_device_write(dev_serial,0,_serial_tx_buf,len);
                    if(len != len_write)
                    {
                        log_e("%s device write err:%d %d",_us_name,len,len_write);
                        waitTime = 10;
                    }
                    else
                    {
                        waitTime = 2000;
                    }

if(rt_mutex_take(dynamic_mutex, 10) == RT_EOK)
                    {
                        rt_ringbuffer_del(&Serial_Tx_ringbuffer, len_write);
                        rt_mutex_release(dynamic_mutex);
                    }
                    result = true;
                }
                else
                {
                    rt_sem_release(serial_tx_sem);
                }
            }
            else
            {
                log_e("%s mutex err",_us_name);
                rt_sem_release(serial_tx_sem);
            }
        }
        else
        {
            log_e("not Tx Com Sem %s",_us_name);
            rt_ringbuffer_reset(&Serial_Tx_ringbuffer);
        }
    }

return result;
}

static rt_err_t _tx_done(rt_device_t dev, void *buffer)
{
    Serial *serial = (Serial *)dev->user_data;
    if (serial != RT_NULL)
    {
        serial->TxDone();
    }

return RT_EOK;
}

void _tx_thread(void *p)
{
    Serial *serial = (Serial *)p;
    serial->StartTxProcess();
}

Serial::Serial(struct serial_app_config serial_cfg)
{
    rt_strncpy(_us_name, serial_cfg.usname, sizeof(_us_name));
    dev_serial = rt_device_find(_us_name);
    if (dev_serial == RT_NULL)
    {
        log_e("Device %s not found!", _us_name);
        return;
    }

// Initialize other members and resources
    // ...

rt_device_set_tx_complete(dev_serial, _tx_done);
    rt_device_open(dev_serial, RT_DEVICE_OFLAG_RDWR | RT_DEVICE_FLAG_INT_RX | RT_DEVICE_FLAG_DMA_TX);

// ....

rt_thread_t th;
    th = rt_thread_create("tx_thread", _tx_thread, this, 1024, 25, 10);
    rt_thread_startup(th);
}

```