Add base priority get APIs (#818)

* Add base priority get APIs
* Add MPU changes

---------

Signed-off-by: Gaurav Aggarwal <aggarg@amazon.com>
Co-authored-by: kar-rahul-aws <118818625+kar-rahul-aws@users.noreply.github.com>
Co-authored-by: Gaurav Aggarwal <aggarg@amazon.com>

include/FreeRTOS.h

@@ -1714,6 +1714,22 @@
     #define traceRETURN_uxTaskPriorityGetFromISR( uxReturn )
 #endif
 
+#ifndef traceENTER_uxTaskBasePriorityGet
+    #define traceENTER_uxTaskBasePriorityGet( xTask )
+#endif
+
+#ifndef traceRETURN_uxTaskBasePriorityGet
+    #define traceRETURN_uxTaskBasePriorityGet( uxReturn )
+#endif
+
+#ifndef traceENTER_uxTaskBasePriorityGetFromISR
+    #define traceENTER_uxTaskBasePriorityGetFromISR( xTask )
+#endif
+
+#ifndef traceRETURN_uxTaskBasePriorityGetFromISR
+    #define traceRETURN_uxTaskBasePriorityGetFromISR( uxReturn )
+#endif
+
 #ifndef traceENTER_vTaskPrioritySet
     #define traceENTER_vTaskPrioritySet( xTask, uxNewPriority )
 #endif

include/mpu_prototypes.h

@@ -128,6 +128,8 @@ BaseType_t MPU_xTaskGetStaticBuffers( TaskHandle_t xTask,
                                       StackType_t ** ppuxStackBuffer,
                                       StaticTask_t ** ppxTaskBuffer ) PRIVILEGED_FUNCTION;
 UBaseType_t MPU_uxTaskPriorityGetFromISR( const TaskHandle_t xTask ) PRIVILEGED_FUNCTION;
+UBaseType_t MPU_uxTaskBasePriorityGet( const TaskHandle_t xTask ) PRIVILEGED_FUNCTION;
+UBaseType_t MPU_uxTaskBasePriorityGetFromISR( const TaskHandle_t xTask ) PRIVILEGED_FUNCTION;
 BaseType_t MPU_xTaskResumeFromISR( TaskHandle_t xTaskToResume ) PRIVILEGED_FUNCTION;
 TaskHookFunction_t MPU_xTaskGetApplicationTaskTagFromISR( TaskHandle_t xTask ) PRIVILEGED_FUNCTION;
 BaseType_t MPU_xTaskGenericNotifyFromISR( TaskHandle_t xTaskToNotify,

include/mpu_wrappers.h

@@ -99,6 +99,8 @@
             #define vTaskAllocateMPURegions              MPU_vTaskAllocateMPURegions
             #define xTaskGetStaticBuffers                MPU_xTaskGetStaticBuffers
             #define uxTaskPriorityGetFromISR             MPU_uxTaskPriorityGetFromISR
+            #define uxTaskBasePriorityGet                MPU_uxTaskBasePriorityGet
+            #define uxTaskBasePriorityGetFromISR         MPU_uxTaskBasePriorityGetFromISR
             #define xTaskResumeFromISR                   MPU_xTaskResumeFromISR
             #define xTaskGetApplicationTaskTagFromISR    MPU_xTaskGetApplicationTaskTagFromISR
             #define xTaskGenericNotifyFromISR            MPU_xTaskGenericNotifyFromISR

include/task.h

@@ -1021,6 +1021,37 @@ UBaseType_t uxTaskPriorityGet( const TaskHandle_t xTask ) PRIVILEGED_FUNCTION;
  */
 UBaseType_t uxTaskPriorityGetFromISR( const TaskHandle_t xTask ) PRIVILEGED_FUNCTION;
 
+/**
+ * task. h
+ * @code{c}
+ * UBaseType_t uxTaskBasePriorityGet( const TaskHandle_t xTask );
+ * @endcode
+ *
+ * INCLUDE_uxTaskPriorityGet and configUSE_MUTEXES must be defined as 1 for this
+ * function to be available. See the configuration section for more information.
+ *
+ * Obtain the base priority of any task.
+ *
+ * @param xTask Handle of the task to be queried.  Passing a NULL
+ * handle results in the base priority of the calling task being returned.
+ *
+ * @return The base priority of xTask.
+ *
+ * \defgroup uxTaskPriorityGet uxTaskBasePriorityGet
+ * \ingroup TaskCtrl
+ */
+UBaseType_t uxTaskBasePriorityGet( const TaskHandle_t xTask ) PRIVILEGED_FUNCTION;
+
+/**
+ * task. h
+ * @code{c}
+ * UBaseType_t uxTaskBasePriorityGetFromISR( const TaskHandle_t xTask );
+ * @endcode
+ *
+ * A version of uxTaskBasePriorityGet() that can be used from an ISR.
+ */
+UBaseType_t uxTaskBasePriorityGetFromISR( const TaskHandle_t xTask ) PRIVILEGED_FUNCTION;
+
 /**
  * task. h
  * @code{c}

portable/Common/mpu_wrappers_v2.c

@@ -1894,6 +1894,72 @@
     #endif /* #if ( INCLUDE_uxTaskPriorityGet == 1 ) */
 /*-----------------------------------------------------------*/
 
+    #if ( ( INCLUDE_uxTaskPriorityGet == 1 ) && ( configUSE_MUTEXES == 1 ) )
+
+        UBaseType_t MPU_uxTaskBasePriorityGet( const TaskHandle_t xTask ) /* PRIVILEGED_FUNCTION */
+        {
+            UBaseType_t uxReturn = configMAX_PRIORITIES;
+            int32_t lIndex;
+            TaskHandle_t xInternalTaskHandle = NULL;
+
+            if( xTask == NULL )
+            {
+                uxReturn = uxTaskBasePriorityGet( xTask );
+            }
+            else
+            {
+                lIndex = ( int32_t ) xTask;
+
+                if( IS_EXTERNAL_INDEX_VALID( lIndex ) != pdFALSE )
+                {
+                    xInternalTaskHandle = MPU_GetTaskHandleAtIndex( CONVERT_TO_INTERNAL_INDEX( lIndex ) );
+
+                    if( xInternalTaskHandle != NULL )
+                    {
+                        uxReturn = uxTaskBasePriorityGet( xInternalTaskHandle );
+                    }
+                }
+            }
+
+            return uxReturn;
+        }
+
+    #endif /* #if ( ( INCLUDE_uxTaskPriorityGet == 1 ) && ( configUSE_MUTEXES == 1 ) ) */
+/*-----------------------------------------------------------*/
+
+    #if ( ( INCLUDE_uxTaskPriorityGet == 1 ) && ( configUSE_MUTEXES == 1 ) )
+
+        UBaseType_t MPU_uxTaskBasePriorityGetFromISR( const TaskHandle_t xTask ) /* PRIVILEGED_FUNCTION */
+        {
+            UBaseType_t uxReturn = configMAX_PRIORITIES;
+            int32_t lIndex;
+            TaskHandle_t xInternalTaskHandle = NULL;
+
+            if( xTask == NULL )
+            {
+                uxReturn = uxTaskBasePriorityGetFromISR( xTask );
+            }
+            else
+            {
+                lIndex = ( int32_t ) xTask;
+
+                if( IS_EXTERNAL_INDEX_VALID( lIndex ) != pdFALSE )
+                {
+                    xInternalTaskHandle = MPU_GetTaskHandleAtIndex( CONVERT_TO_INTERNAL_INDEX( lIndex ) );
+
+                    if( xInternalTaskHandle != NULL )
+                    {
+                        uxReturn = uxTaskBasePriorityGetFromISR( xInternalTaskHandle );
+                    }
+                }
+            }
+
+            return uxReturn;
+        }
+
+    #endif /* #if ( ( INCLUDE_uxTaskPriorityGet == 1 ) && ( configUSE_MUTEXES == 1 ) ) */
+/*-----------------------------------------------------------*/
+
     #if ( ( INCLUDE_xTaskResumeFromISR == 1 ) && ( INCLUDE_vTaskSuspend == 1 ) )
 
         BaseType_t MPU_xTaskResumeFromISR( TaskHandle_t xTaskToResume ) /* PRIVILEGED_FUNCTION */

tasks.c

@@ -2669,6 +2669,77 @@ static void prvInitialiseNewTask( TaskFunction_t pxTaskCode,
 #endif /* INCLUDE_uxTaskPriorityGet */
 /*-----------------------------------------------------------*/
 
+#if ( ( INCLUDE_uxTaskPriorityGet == 1 ) && ( configUSE_MUTEXES == 1 ) )
+
+    UBaseType_t uxTaskBasePriorityGet( const TaskHandle_t xTask )
+    {
+        TCB_t const * pxTCB;
+        UBaseType_t uxReturn;
+
+        traceENTER_uxTaskBasePriorityGet( xTask );
+
+        taskENTER_CRITICAL();
+        {
+            /* If null is passed in here then it is the base priority of the task
+             * that called uxTaskBasePriorityGet() that is being queried. */
+            pxTCB = prvGetTCBFromHandle( xTask );
+            uxReturn = pxTCB->uxBasePriority;
+        }
+        taskEXIT_CRITICAL();
+
+        traceRETURN_uxTaskBasePriorityGet( uxReturn );
+
+        return uxReturn;
+    }
+
+#endif /* #if ( ( INCLUDE_uxTaskPriorityGet == 1 ) && ( configUSE_MUTEXES == 1 ) ) */
+/*-----------------------------------------------------------*/
+
+#if ( ( INCLUDE_uxTaskPriorityGet == 1 ) && ( configUSE_MUTEXES == 1 ) )
+
+    UBaseType_t uxTaskBasePriorityGetFromISR( const TaskHandle_t xTask )
+    {
+        TCB_t const * pxTCB;
+        UBaseType_t uxReturn;
+        UBaseType_t uxSavedInterruptStatus;
+
+        traceENTER_uxTaskBasePriorityGetFromISR( xTask );
+
+        /* RTOS ports that support interrupt nesting have the concept of a
+         * maximum  system call (or maximum API call) interrupt priority.
+         * Interrupts that are  above the maximum system call priority are keep
+         * permanently enabled, even when the RTOS kernel is in a critical section,
+         * but cannot make any calls to FreeRTOS API functions.  If configASSERT()
+         * is defined in FreeRTOSConfig.h then
+         * portASSERT_IF_INTERRUPT_PRIORITY_INVALID() will result in an assertion
+         * failure if a FreeRTOS API function is called from an interrupt that has
+         * been assigned a priority above the configured maximum system call
+         * priority.  Only FreeRTOS functions that end in FromISR can be called
+         * from interrupts  that have been assigned a priority at or (logically)
+         * below the maximum system call interrupt priority.  FreeRTOS maintains a
+         * separate interrupt safe API to ensure interrupt entry is as fast and as
+         * simple as possible.  More information (albeit Cortex-M specific) is
+         * provided on the following link:
+         * https://www.FreeRTOS.org/RTOS-Cortex-M3-M4.html */
+        portASSERT_IF_INTERRUPT_PRIORITY_INVALID();
+
+        uxSavedInterruptStatus = taskENTER_CRITICAL_FROM_ISR();
+        {
+            /* If null is passed in here then it is the base priority of the calling
+             * task that is being queried. */
+            pxTCB = prvGetTCBFromHandle( xTask );
+            uxReturn = pxTCB->uxBasePriority;
+        }
+        taskEXIT_CRITICAL_FROM_ISR( uxSavedInterruptStatus );
+
+        traceRETURN_uxTaskBasePriorityGetFromISR( uxReturn );
+
+        return uxReturn;
+    }
+
+#endif /* #if ( ( INCLUDE_uxTaskPriorityGet == 1 ) && ( configUSE_MUTEXES == 1 ) ) */
+/*-----------------------------------------------------------*/
+
 #if ( INCLUDE_vTaskPrioritySet == 1 )
 
     void vTaskPrioritySet( TaskHandle_t xTask,