feat(freertos-smp): Add support for queue direct transfer buffer in task TCB

This commit adds support for queue direct transfer buffer being owned by
the task's TCB. This inherently solves some design issues with the
buffer being owned by the queue's object. On the flip side, this adds
memory cost to the task's TCB.

Author: sudeep-mohanty

include/FreeRTOS.h

@@ -3291,6 +3291,11 @@ typedef struct xSTATIC_TCB
     #if ( configUSE_POSIX_ERRNO == 1 )
         int iDummy22;
     #endif
+
+    #if ( configQUEUE_DIRECT_TRANSFER == 1 )
+        void * pvDummyDirectTransferBuffer;
+        BaseType_t xDummyDirectTransferPosition;
+    #endif
 } StaticTask_t;
 
 /*
@@ -3337,11 +3342,6 @@ typedef struct xSTATIC_QUEUE
     #if ( ( portUSING_GRANULAR_LOCKS == 1 ) && ( configNUMBER_OF_CORES > 1 ) )
         portSPINLOCK_TYPE xDummySpinlock[ 2 ];
     #endif /* #if ( ( portUSING_GRANULAR_LOCKS == 1 ) && ( configNUMBER_OF_CORES > 1 ) ) */
-
-    #if ( configQUEUE_DIRECT_TRANSFER == 1 )
-        void * pvDummyDirectTransferBuffer;
-        BaseType_t xDummyDirectTransferPosition;
-    #endif
 } StaticQueue_t;
 typedef StaticQueue_t StaticSemaphore_t;
 

include/task.h

@@ -3758,6 +3758,68 @@ BaseType_t xTaskRemoveFromEventListFromISR( const List_t * const pxEventList ) P
 void vTaskRemoveFromUnorderedEventList( ListItem_t * pxEventListItem,
                                         const TickType_t xItemValue ) PRIVILEGED_FUNCTION;
 
+#if ( configQUEUE_DIRECT_TRANSFER == 1 )
+
+/*
+ * THIS FUNCTION MUST NOT BE USED FROM APPLICATION CODE.  IT IS AN
+ * INTERFACE FOR THE EXCLUSIVE USE OF THE QUEUE IMPLEMENTATION.
+ *
+ * Set the direct transfer buffer for the current task.
+ * Called when a task is about to block on a queue operation.
+ */
+    void vTaskSetDirectTransferBuffer( void * pvBuffer,
+                                       BaseType_t xPosition,
+                                       TaskHandle_t xTask ) PRIVILEGED_FUNCTION;
+
+/*
+ * THIS FUNCTION MUST NOT BE USED FROM APPLICATION CODE.  IT IS AN
+ * INTERFACE FOR THE EXCLUSIVE USE OF THE QUEUE IMPLEMENTATION.
+ *
+ * Clear the direct transfer buffer for a task.
+ * @param xTask The task handle
+ */
+    void vTaskClearDirectTransferBuffer( TaskHandle_t xTask ) PRIVILEGED_FUNCTION;
+
+/*
+ * THIS FUNCTION MUST NOT BE USED FROM APPLICATION CODE.  IT IS AN
+ * INTERFACE FOR THE EXCLUSIVE USE OF THE QUEUE IMPLEMENTATION.
+ *
+ * Get the direct transfer buffer pointer from a task.
+ * @param xTask The task handle
+ * @return The buffer pointer, or NULL if not set
+ *
+ */
+    void * pvTaskGetDirectTransferBuffer( TaskHandle_t xTask ) PRIVILEGED_FUNCTION;
+
+/*
+ * THIS FUNCTION MUST NOT BE USED FROM APPLICATION CODE.  IT IS AN
+ * INTERFACE FOR THE EXCLUSIVE USE OF THE QUEUE IMPLEMENTATION.
+ *
+ * Get the direct transfer position from a task.
+ * @param xTask The task handle
+ * @return The position, or -1 if not set
+ *
+ */
+    BaseType_t xTaskGetDirectTransferPosition( TaskHandle_t xTask ) PRIVILEGED_FUNCTION;
+
+/*
+ * THIS FUNCTION MUST NOT BE USED FROM APPLICATION CODE.  IT IS AN
+ * INTERFACE FOR THE EXCLUSIVE USE OF THE QUEUE IMPLEMENTATION.
+ *
+ * Get the highest priority task from an event list if it has armed direct transfer.
+ * Checks only the head of the event list (O(1) operation) for deterministic behavior.
+ *
+ * If the highest priority task hasn't armed direct transfer (e.g., using xQueuePeek()),
+ * returns NULL and direct transfer is skipped for this operation. This is acceptable since
+ * direct transfer is an optimization, not a requirement.
+ *
+ * @param pxEventList The event list to check
+ * @return Task handle of highest priority task if it has armed transfer, or NULL otherwise
+ */
+    TaskHandle_t xTaskGetHighestPriorityTaskWithDirectTransferArmed( const List_t * const pxEventList ) PRIVILEGED_FUNCTION;
+
+#endif /* configQUEUE_DIRECT_TRANSFER */
+
 /*
  * THIS FUNCTION MUST NOT BE USED FROM APPLICATION CODE.  IT IS ONLY
  * INTENDED FOR USE WHEN IMPLEMENTING A PORT OF THE SCHEDULER AND IS