Function xQueueGiveMutexRecursive

queue.c:620–668

#if ( configUSE_RECURSIVE_MUTEXES == 1 )

    BaseType_t xQueueGiveMutexRecursive( QueueHandle_t xMutex )
    {
        BaseType_t xReturn;
        Queue_t * const pxMutex = ( Queue_t * ) xMutex;

        configASSERT( pxMutex );

        /* If this is the task that holds the mutex then xMutexHolder will not
         * change outside of this task.  If this task does not hold the mutex then
         * pxMutexHolder can never coincidentally equal the tasks handle, and as
         * this is the only condition we are interested in it does not matter if
         * pxMutexHolder is accessed simultaneously by another task.  Therefore no
         * mutual exclusion is required to test the pxMutexHolder variable. */
        if( pxMutex->u.xSemaphore.xMutexHolder == xTaskGetCurrentTaskHandle() )
        {
            traceGIVE_MUTEX_RECURSIVE( pxMutex );

            /* uxRecursiveCallCount cannot be zero if xMutexHolder is equal to
             * the task handle, therefore no underflow check is required.  Also,
             * uxRecursiveCallCount is only modified by the mutex holder, and as
             * there can only be one, no mutual exclusion is required to modify the
             * uxRecursiveCallCount member. */
            ( pxMutex->u.xSemaphore.uxRecursiveCallCount )--;

            /* Has the recursive call count unwound to 0? */
            if( pxMutex->u.xSemaphore.uxRecursiveCallCount == ( UBaseType_t ) 0 )
            {
                /* Return the mutex.  This will automatically unblock any other
                 * task that might be waiting to access the mutex. */
                ( void ) xQueueGenericSend( pxMutex, NULL, queueMUTEX_GIVE_BLOCK_TIME, queueSEND_TO_BACK );
            }
            else
            {
                mtCOVERAGE_TEST_MARKER();
            }

            xReturn = pdPASS;
        }
        else
        {
            /* The mutex cannot be given because the calling task is not the
             * holder. */
            xReturn = pdFAIL;

            traceGIVE_MUTEX_RECURSIVE_FAILED( pxMutex );
        }

        return xReturn;
    }

#endif /* configUSE_RECURSIVE_MUTEXES */
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