FreeRTOS中的互斥锁在中断中Give

shipeng

FreeRTOS中的互斥锁在中断中Give [复制链接]

 

新手第一次使用FreeRTOS的互斥锁，本想用它来指示串口发送DMA的占用情况，在DMA传输完成中断中Give串口发送DMA互斥量（xSemaphoreGiveFromISR）。结果系统始终无法正常运行起来。由于一次修改了多处代码一时定位不到问题点。只知道调试串口打印出“FreeRTOS assert "!( ( pxQueue->uxQueueType == queueQUEUE_IS_MUTEX ) && ( pxQueue->u.xSemaphore.xMute...”的消息。网上找了一圈，发现大家都说FreeRTOS的互斥锁功能不完整，本来互斥量应该遵循谁上锁谁解锁的原则，结果FreeRTOS却没能实现这个功能，他的互斥锁上锁后所有人都可以解锁。于是我便坚定了中断中也可以解锁互斥量。但是一通折腾下来始终不能成功运行，最后无意中看到宏“xSemaphoreGiveFromISR”的使用前注释才发现了问题所在：

 

Mutex type semaphores (those created using a call to xSemaphoreCreateMutex()) must not be used with this macro.

原来虽然FreeRTOS不能实现谁上锁谁开锁这个功能，但是他还是稍微做了下弥补，那就是中断函数中不允许Give互斥量。

Jacktang

FreeRTOS不能实现谁上锁谁开锁这个功能，但是他还是稍微做了下弥补，那就是中断函数中不允许Give互斥量

非常感谢分享

jobszheng5

我对FreeRTOS中的互斥锁的理解也不深。

看来未来也需要加强一下

lugl4313820

现在最新版的好象说修复了这个问题，楼主可以去试试。

shipeng

lugl4313820 发表于 2023-12-23 10:15 现在最新版的好象说修复了这个问题，楼主可以去试试。

不知道我用的是不是最新版，总之用了互斥量就一堆的问题，各种报Assert错误，我也不知道是不是因为谁上锁谁解锁的原因导致的。总之如果遵循谁上锁谁解锁的原则使用互斥量就可以运行。否则就会报各种ASSERT错误。如果把互斥量换成二值信号量就没有这个问题。

下面是我的源码，说一下我的软件逻辑：每次DMA传输完成后启动一个10毫秒定时器，在定时器回调函数中Give互斥量。从而保证帧最小间隔为10毫秒，以防止发送帧粘连。

婢跺秴鍩�

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SemaphoreHandle_t DMA2C5MuxSem_Handle = NULL;

TimerHandle_t xHandleTimerU4Tx = NULL;

TaskHandle_t xHandleTaskU4TX = NULL;

static void U4TxTimerCallback(void);
static void CreateU4TxFrameDelay(TickType_t xTimerPeriodInTicks );
static void vTaskU4TX_Handler(void *pvParameters);
void UART4_DMA_Init(void);
void BSP_UART4_Init(void);

void BSP_USART_Config(void)
{
	BSP_UART4_Init();
	UART4_DMA_Init();
	NVIC_EnableIRQRequest(UART4_IRQn, 2, 0);
	USART_EnableInterrupt(UART4, USART_INT_IDLE);
	/* Enable UART4 RX and UART4 TX DMA */
	USART_EnableDMA(UART4, USART_DMA_TX_RX);
	U4RxQueue = xQueueCreate(U4RX_QUE_DEPTH, U4RX_QUE_SIZE);//msgs , length of msg(byte)
	if (NULL==U4RxQueue)printf("U4RxQueue Creating Failed!\r\n");
	U4TxQueue = xQueueCreate(4, 4);
	if (NULL==U4TxQueue)printf("U4TxQueue Creating Failed!\r\n");
	#ifndef	USE_DMA_WITH_MUTEX
	DMA2C5MuxSem_Handle = xSemaphoreCreateBinary();
	#else
	DMA2C5MuxSem_Handle = xSemaphoreCreateMutex();
	#endif
	if (NULL==DMA2C5MuxSem_Handle)printf("DMA2C5MuxSem Creating Failed!\r\n");
	#ifndef	USE_DMA_WITH_MUTEX
	else if (0==uxSemaphoreGetCount(DMA2C5MuxSem_Handle) && pdPASS!=xSemaphoreGive(DMA2C5MuxSem_Handle))printf("DMA2C5MuxSem Giving Failed!\r\n");
	#endif
	CreateU4TxFrameDelay(10);
	xTaskCreate((TaskFunction_t )vTaskU4TX_Handler,
							(const char*    )"UART4 TX Task",
							(uint16_t       )256,
							(void*          )NULL,
							(UBaseType_t    )5,
							(TaskHandle_t*  )&xHandleTaskU4TX);

}

static void U4TxTimerCallback(void)
{
	#ifndef	USE_DMA_WITH_MUTEX
	if (0==uxSemaphoreGetCount(DMA2C5MuxSem_Handle) && pdPASS != xSemaphoreGive( DMA2C5MuxSem_Handle))printf("DMA2C5MuxSem Giving failed!");
	#else
	if (NULL!=xSemaphoreGetMutexHolder(DMA2C5MuxSem_Handle) && pdPASS != xSemaphoreGive( DMA2C5MuxSem_Handle))printf("DMA2C5MuxSem Giving failed!");
	#endif
	else if (0!=uxQueueMessagesWaiting(U4TxQueue))portYIELD();//if the queue is not empty,then request a context switch
}

static void CreateU4TxFrameDelay(TickType_t xTimerPeriodInTicks )
{
	xHandleTimerU4Tx = xTimerCreate("U4TxTimer",xTimerPeriodInTicks,pdFALSE,(void*)3,(TimerCallbackFunction_t)U4TxTimerCallback);
	if (NULL==xHandleTimerU4Tx)printf("U4TxTimer Creating failed!");
}

static void vTaskU4TX_Handler(void *pvParameters)
{
	UsartTxRxBuffer_t *tx_buffer;
	while(1)
	{
		if (pdPASS==xQueueReceive(U4TxQueue, (uint8_t*)&tx_buffer, portMAX_DELAY))
		{
			xSemaphoreTake(DMA2C5MuxSem_Handle, 5689U);//5689ms Is The MAX  TIME of DMA-UART-Tx,65536bytes*1000ms/11520(byte rate)=5688.888...
			if (0!=tx_buffer->length)
			{
				/* Disable TX DMA */
				DMA_Disable(DMA2_Channel5);
				memcpy(DMA_UART4_TxBuf,tx_buffer->DatArea,tx_buffer->length);
				DMA2_Channel5->CHNDATA_B.NDATA = tx_buffer->length;
				/* Enable TX DMA */
				DMA_Enable(DMA2_Channel5);
			}
			if (NULL!=tx_buffer)vPortFree((uint8_t*)tx_buffer);
		}
	}
}

void DMA2_Channel5_IRQHandler(void)
{
	if (RESET != DMA_ReadIntFlag(DMA2_INT_FLAG_TC5))
	{
		BaseType_t xHigherPriorityTaskWoken = pdFALSE;
		DMA_ClearIntFlag(DMA2_INT_FLAG_TC5);
		if (NULL!=xHandleTimerU4Tx)
		{
			xTimerResetFromISR(xHandleTimerU4Tx,&xHigherPriorityTaskWoken);
		}
	}
}

void UART4_DMA_Init(void)
{
	DMA_Config_T dmaConfig;

	/* Enable DMA Clock */
	RCM_EnableAHBPeriphClock(RCM_AHB_PERIPH_DMA2);

	/* TX DMA config */
	dmaConfig.peripheralBaseAddr = UART4_DR_ADDRESS;
	dmaConfig.memoryBaseAddr = (uint32_t)DMA_UART4_TxBuf;
	dmaConfig.dir = DMA_DIR_PERIPHERAL_DST;
	dmaConfig.bufferSize = 0;
	dmaConfig.peripheralInc = DMA_PERIPHERAL_INC_DISABLE;
	dmaConfig.memoryInc = DMA_MEMORY_INC_ENABLE;
	dmaConfig.peripheralDataSize = DMA_PERIPHERAL_DATA_SIZE_BYTE;
	dmaConfig.memoryDataSize = DMA_MEMORY_DATA_SIZE_BYTE;
	dmaConfig.loopMode = DMA_MODE_NORMAL;
	dmaConfig.priority = DMA_PRIORITY_HIGH;
	dmaConfig.M2M = DMA_M2MEN_DISABLE;

	/* Enable DMA channel */
	DMA_Config(DMA2_Channel5, &dmaConfig);

	/* Enable TX DMA */
	DMA_Enable(DMA2_Channel5);

	NVIC_EnableIRQRequest(DMA2_Channel5_IRQn, 3, 0);
	DMA_EnableInterrupt(DMA2_Channel5, DMA_INT_TC);

	/* RX DMA Configure */
	dmaConfig.dir = DMA_DIR_PERIPHERAL_SRC;
	dmaConfig.loopMode = DMA_MODE_CIRCULAR;
	dmaConfig.bufferSize = sizeof(DMA_UART4_RxBuf);
	dmaConfig.memoryBaseAddr = (uint32_t)DMA_UART4_RxBuf;
	/* Enable DMA channel */
	DMA_Config(DMA2_Channel3, &dmaConfig);

	/* Enable RX DMA */
	DMA_Enable(DMA2_Channel3);

//	NVIC_EnableIRQRequest(DMA2_Channel3_IRQn, 1, 0);
//	DMA_EnableInterrupt(DMA2_Channel3, DMA_INT_TC);
}

void BSP_UART4_Init(void)
{
	GPIO_Config_T GPIO_ConfigStructure;
	USART_Config_T USART_ConfigStruct;

	RCM_EnableAPB2PeriphClock((RCM_APB2_PERIPH_T)(RCM_APB2_PERIPH_GPIOC));
	RCM_EnableAPB1PeriphClock((RCM_APB1_PERIPH_T)(RCM_APB1_PERIPH_UART4));

	/*Uart4 TX*/
	GPIO_ConfigStructure.pin = GPIO_PIN_10;
	GPIO_ConfigStructure.speed = GPIO_SPEED_50MHz;
	GPIO_ConfigStructure.mode = GPIO_MODE_AF_PP;
	GPIO_Config(GPIOC, &GPIO_ConfigStructure);

	/*Uart4 RX*/
	GPIO_ConfigStructure.pin = GPIO_PIN_11;
	GPIO_ConfigStructure.mode = GPIO_MODE_IN_FLOATING;
	GPIO_Config(GPIOC, &GPIO_ConfigStructure);

	USART_ConfigStruct.baudRate = 115200;
	USART_ConfigStruct.hardwareFlow = USART_HARDWARE_FLOW_NONE;
	USART_ConfigStruct.mode = USART_MODE_TX_RX;
	USART_ConfigStruct.parity = USART_PARITY_NONE;
	USART_ConfigStruct.stopBits = USART_STOP_BIT_1;
	USART_ConfigStruct.wordLength = USART_WORD_LEN_8B;
	USART_Config(UART4, &USART_ConfigStruct);

	USART_Enable(UART4);

}

 

lugl4313820

前段时间管管发了一个帖子，说freertos升级到了最新版了的，你可以去看看。

freebsder

我记得是可以的呀，应该是10版本以上。

hailan365

同意版主大大，升级试试看