Source code learning - [FreeRTOS] privileged_ Understanding of function meaning

introduction

PRIVILEGED_FUNCTION The identifier is in the author's view xTaskNotify when , Found this identifier ：

BaseType_t xTaskGenericNotify( TaskHandle_t xTaskToNotify, uint32_t ulValue, eNotifyAction eAction, uint32_t *pulPreviousNotificationValue ) PRIVILEGED_FUNCTION;
#define xTaskNotify( xTaskToNotify, ulValue, eAction ) xTaskGenericNotify( ( xTaskToNotify ), ( ulValue ), ( eAction ), NULL )
#define xTaskNotifyAndQuery( xTaskToNotify, ulValue, eAction, pulPreviousNotifyValue ) xTaskGenericNotify( ( xTaskToNotify ), ( ulValue ), ( eAction ), ( pulPreviousNotifyValue ) )

This PRIVILEGED_FUNCTION What an identifier means , And the impact on the function ？

PRIVILEGED_FUNCTION Macro definition source of

stay mpu_wrappers.h Found in the PRIVILEGED_FUNCTION The macro definition of （）：

/* * FreeRTOS Kernel V10.2.1 * Copyright (C) 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved. * * Permission is hereby granted, free of charge, to any person obtaining a copy of * this software and associated documentation files (the "Software"), to deal in * the Software without restriction, including without limitation the rights to * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of * the Software, and to permit persons to whom the Software is furnished to do so, * subject to the following conditions: * * The above copyright notice and this permission notice shall be included in all * copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. * * http://www.FreeRTOS.org * http://aws.amazon.com/freertos * * 1 tab == 4 spaces! */

#ifndef MPU_WRAPPERS_H
#define MPU_WRAPPERS_H

/* This file redefines API functions to be called through a wrapper macro, but only for ports that are using the MPU. */
#ifdef portUSING_MPU_WRAPPERS

	/* MPU_WRAPPERS_INCLUDED_FROM_API_FILE will be defined when this file is included from queue.c or task.c to prevent it from having an effect within those files. */
	#ifndef MPU_WRAPPERS_INCLUDED_FROM_API_FILE

		/* * Map standard (non MPU) API functions to equivalents that start * "MPU_". This will cause the application code to call the MPU_ * version, which wraps the non-MPU version with privilege promoting * then demoting code, so the kernel code always runs will full * privileges. */

		/* Map standard tasks.h API functions to the MPU equivalents. */
		#define xTaskCreate MPU_xTaskCreate
		#define xTaskCreateStatic MPU_xTaskCreateStatic
		#define xTaskCreateRestricted MPU_xTaskCreateRestricted
		#define vTaskAllocateMPURegions MPU_vTaskAllocateMPURegions
		#define vTaskDelete MPU_vTaskDelete
		#define vTaskDelay MPU_vTaskDelay
		#define vTaskDelayUntil MPU_vTaskDelayUntil
		// .....  Macro encapsulation of some functions   Omit 
		#define xQueueRemoveFromSet MPU_xQueueRemoveFromSet
		#define xQueueSelectFromSet MPU_xQueueSelectFromSet
		#define xQueueGenericReset MPU_xQueueGenericReset

		#if( configQUEUE_REGISTRY_SIZE > 0 )
			#define vQueueAddToRegistry MPU_vQueueAddToRegistry
			#define vQueueUnregisterQueue MPU_vQueueUnregisterQueue
			#define pcQueueGetName MPU_pcQueueGetName
		#endif

		/* Map standard timer.h API functions to the MPU equivalents. */
		#define xTimerCreate MPU_xTimerCreate
		#define xTimerCreateStatic MPU_xTimerCreateStatic
		#define pvTimerGetTimerID MPU_pvTimerGetTimerID
		#define vTimerSetTimerID MPU_vTimerSetTimerID
		#define xTimerIsTimerActive MPU_xTimerIsTimerActive
		#define xTimerGetTimerDaemonTaskHandle MPU_xTimerGetTimerDaemonTaskHandle
		#define xTimerPendFunctionCall MPU_xTimerPendFunctionCall
		#define pcTimerGetName MPU_pcTimerGetName
		#define vTimerSetReloadMode MPU_vTimerSetReloadMode
		#define xTimerGetPeriod MPU_xTimerGetPeriod
		#define xTimerGetExpiryTime MPU_xTimerGetExpiryTime
		#define xTimerGenericCommand MPU_xTimerGenericCommand

		/* Map standard event_group.h API functions to the MPU equivalents. */
		#define xEventGroupCreate MPU_xEventGroupCreate
		#define xEventGroupCreateStatic MPU_xEventGroupCreateStatic
		#define xEventGroupWaitBits MPU_xEventGroupWaitBits
		#define xEventGroupClearBits MPU_xEventGroupClearBits
		#define xEventGroupSetBits MPU_xEventGroupSetBits
		#define xEventGroupSync MPU_xEventGroupSync
		#define vEventGroupDelete MPU_vEventGroupDelete

		/* Map standard message/stream_buffer.h API functions to the MPU equivalents. */
		#define xStreamBufferSend MPU_xStreamBufferSend
		#define xStreamBufferReceive MPU_xStreamBufferReceive
		#define xStreamBufferNextMessageLengthBytes MPU_xStreamBufferNextMessageLengthBytes
		#define vStreamBufferDelete MPU_vStreamBufferDelete
		#define xStreamBufferIsFull MPU_xStreamBufferIsFull
		#define xStreamBufferIsEmpty MPU_xStreamBufferIsEmpty
		#define xStreamBufferReset MPU_xStreamBufferReset
		#define xStreamBufferSpacesAvailable MPU_xStreamBufferSpacesAvailable
		#define xStreamBufferBytesAvailable MPU_xStreamBufferBytesAvailable
		#define xStreamBufferSetTriggerLevel MPU_xStreamBufferSetTriggerLevel
		#define xStreamBufferGenericCreate MPU_xStreamBufferGenericCreate
		#define xStreamBufferGenericCreateStatic MPU_xStreamBufferGenericCreateStatic


		/* Remove the privileged function macro, but keep the PRIVILEGED_DATA macro so applications can place data in privileged access sections (useful when using statically allocated objects). */
		#define PRIVILEGED_FUNCTION
		#define PRIVILEGED_DATA __attribute__((section("privileged_data")))
		#define FREERTOS_SYSTEM_CALL

	#else /* MPU_WRAPPERS_INCLUDED_FROM_API_FILE */

		/* Ensure API functions go in the privileged execution section. */
		#define PRIVILEGED_FUNCTION __attribute__((section("privileged_functions")))
		#define PRIVILEGED_DATA __attribute__((section("privileged_data")))
		#define FREERTOS_SYSTEM_CALL __attribute__((section( "freertos_system_calls")))

	#endif /* MPU_WRAPPERS_INCLUDED_FROM_API_FILE */

#else /* portUSING_MPU_WRAPPERS */

	#define PRIVILEGED_FUNCTION
	#define PRIVILEGED_DATA
	#define FREERTOS_SYSTEM_CALL
	#define portUSING_MPU_WRAPPERS 0

#endif /* portUSING_MPU_WRAPPERS */


#endif /* MPU_WRAPPERS_H */

Check out the code above , Find out PRIVILEGED_FUNCTION With the macro definition portUSING_MPU_WRAPPERS and MPU_WRAPPERS_INCLUDED_FROM_API_FILE Different but different ：

1. Defined portUSING_MPU_WRAPPERS, Undefined MPU_WRAPPERS_INCLUDED_FROM_API_FILE, be #define PRIVILEGED_FUNCTION;
2. Both are defined , be PRIVILEGED_FUNCTION _attribute_((section(“privileged_functions”))), This definition will place the modified function named “privileged_functions” In segment space ;
3. Undefined portUSING_MPU_WRAPPERS, be #define PRIVILEGED_FUNCTION;

namely , as long as portUSING_MPU_WRAPPERS Undefined ,PRIVILEGED_FUNCTION Meaningless ; Otherwise, a segment space will be specified to store the specified function ;

From the segment space, we can see the process from preprocessing to loading

To be added

Reference material

1. FreeRTOS V10.3.1 Source code ;
2. 《 Self cultivation of programmers 》—— Yu Jiazi Shifan Pan Aimin ;