| /* | |
| * FreeRTOS Kernel <DEVELOPMENT BRANCH> | |
| * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved. | |
| * | |
| * SPDX-License-Identifier: MIT | |
| * | |
| * 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. | |
| * | |
| * https://www.FreeRTOS.org | |
| * https://github.com/FreeRTOS | |
| * | |
| */ | |
| /* | |
| * A sample implementation of pvPortMalloc() and vPortFree() that combines | |
| * (coalescences) adjacent memory blocks as they are freed, and in so doing | |
| * limits memory fragmentation. | |
| * | |
| * See heap_1.c, heap_2.c and heap_3.c for alternative implementations, and the | |
| * memory management pages of https://www.FreeRTOS.org for more information. | |
| */ | |
| #include <stdlib.h> | |
| /* Defining MPU_WRAPPERS_INCLUDED_FROM_API_FILE prevents task.h from redefining | |
| * all the API functions to use the MPU wrappers. That should only be done when | |
| * task.h is included from an application file. */ | |
| #define MPU_WRAPPERS_INCLUDED_FROM_API_FILE | |
| #include "FreeRTOS.h" | |
| #include "task.h" | |
| #undef MPU_WRAPPERS_INCLUDED_FROM_API_FILE | |
| #if ( configSUPPORT_DYNAMIC_ALLOCATION == 0 ) | |
| #error This file must not be used if configSUPPORT_DYNAMIC_ALLOCATION is 0 | |
| #endif | |
| /* Block sizes must not get too small. */ | |
| #define heapMINIMUM_BLOCK_SIZE ( ( size_t ) ( xHeapStructSize << 1 ) ) | |
| /* Assumes 8bit bytes! */ | |
| #define heapBITS_PER_BYTE ( ( size_t ) 8 ) | |
| /* Allocate the memory for the heap. */ | |
| #if ( configAPPLICATION_ALLOCATED_HEAP == 1 ) | |
| /* The application writer has already defined the array used for the RTOS | |
| * heap - probably so it can be placed in a special segment or address. */ | |
| extern uint8_t ucHeap[ configTOTAL_HEAP_SIZE ]; | |
| #else | |
| PRIVILEGED_DATA static uint8_t ucHeap[ configTOTAL_HEAP_SIZE ]; | |
| #endif /* configAPPLICATION_ALLOCATED_HEAP */ | |
| /* Define the linked list structure. This is used to link free blocks in order | |
| * of their memory address. */ | |
| typedef struct A_BLOCK_LINK | |
| { | |
| struct A_BLOCK_LINK * pxNextFreeBlock; /*<< The next free block in the list. */ | |
| size_t xBlockSize; /*<< The size of the free block. */ | |
| } BlockLink_t; | |
| /*-----------------------------------------------------------*/ | |
| /* | |
| * Inserts a block of memory that is being freed into the correct position in | |
| * the list of free memory blocks. The block being freed will be merged with | |
| * the block in front it and/or the block behind it if the memory blocks are | |
| * adjacent to each other. | |
| */ | |
| static void prvInsertBlockIntoFreeList( BlockLink_t * pxBlockToInsert ) PRIVILEGED_FUNCTION; | |
| /* | |
| * Called automatically to setup the required heap structures the first time | |
| * pvPortMalloc() is called. | |
| */ | |
| static void prvHeapInit( void ) PRIVILEGED_FUNCTION; | |
| /*-----------------------------------------------------------*/ | |
| /* The size of the structure placed at the beginning of each allocated memory | |
| * block must by correctly byte aligned. */ | |
| static const size_t xHeapStructSize = ( sizeof( BlockLink_t ) + ( ( size_t ) ( portBYTE_ALIGNMENT - 1 ) ) ) & ~( ( size_t ) portBYTE_ALIGNMENT_MASK ); | |
| /* Create a couple of list links to mark the start and end of the list. */ | |
| PRIVILEGED_DATA static BlockLink_t xStart, * pxEnd = NULL; | |
| /* Keeps track of the number of calls to allocate and free memory as well as the | |
| * number of free bytes remaining, but says nothing about fragmentation. */ | |
| PRIVILEGED_DATA static size_t xFreeBytesRemaining = 0U; | |
| PRIVILEGED_DATA static size_t xMinimumEverFreeBytesRemaining = 0U; | |
| PRIVILEGED_DATA static size_t xNumberOfSuccessfulAllocations = 0; | |
| PRIVILEGED_DATA static size_t xNumberOfSuccessfulFrees = 0; | |
| /* Gets set to the top bit of an size_t type. When this bit in the xBlockSize | |
| * member of an BlockLink_t structure is set then the block belongs to the | |
| * application. When the bit is free the block is still part of the free heap | |
| * space. */ | |
| PRIVILEGED_DATA static size_t xBlockAllocatedBit = 0; | |
| /*-----------------------------------------------------------*/ | |
| void * pvPortMalloc( size_t xWantedSize ) | |
| { | |
| BlockLink_t * pxBlock, * pxPreviousBlock, * pxNewBlockLink; | |
| void * pvReturn = NULL; | |
| vTaskSuspendAll(); | |
| { | |
| /* If this is the first call to malloc then the heap will require | |
| * initialisation to setup the list of free blocks. */ | |
| if( pxEnd == NULL ) | |
| { | |
| prvHeapInit(); | |
| } | |
| else | |
| { | |
| mtCOVERAGE_TEST_MARKER(); | |
| } | |
| /* Check the requested block size is not so large that the top bit is | |
| * set. The top bit of the block size member of the BlockLink_t structure | |
| * is used to determine who owns the block - the application or the | |
| * kernel, so it must be free. */ | |
| if( ( xWantedSize & xBlockAllocatedBit ) == 0 ) | |
| { | |
| /* The wanted size must be increased so it can contain a BlockLink_t | |
| * structure in addition to the requested amount of bytes. */ | |
| if( ( xWantedSize > 0 ) && | |
| ( ( xWantedSize + xHeapStructSize ) > xWantedSize ) ) /* Overflow check */ | |
| { | |
| xWantedSize += xHeapStructSize; | |
| /* Ensure that blocks are always aligned. */ | |
| if( ( xWantedSize & portBYTE_ALIGNMENT_MASK ) != 0x00 ) | |
| { | |
| /* Byte alignment required. Check for overflow. */ | |
| if( ( xWantedSize + ( portBYTE_ALIGNMENT - ( xWantedSize & portBYTE_ALIGNMENT_MASK ) ) ) | |
| > xWantedSize ) | |
| { | |
| xWantedSize += ( portBYTE_ALIGNMENT - ( xWantedSize & portBYTE_ALIGNMENT_MASK ) ); | |
| configASSERT( ( xWantedSize & portBYTE_ALIGNMENT_MASK ) == 0 ); | |
| } | |
| else | |
| { | |
| xWantedSize = 0; | |
| } | |
| } | |
| else | |
| { | |
| mtCOVERAGE_TEST_MARKER(); | |
| } | |
| } | |
| else | |
| { | |
| xWantedSize = 0; | |
| } | |
| if( ( xWantedSize > 0 ) && ( xWantedSize <= xFreeBytesRemaining ) ) | |
| { | |
| /* Traverse the list from the start (lowest address) block until | |
| * one of adequate size is found. */ | |
| pxPreviousBlock = &xStart; | |
| pxBlock = xStart.pxNextFreeBlock; | |
| while( ( pxBlock->xBlockSize < xWantedSize ) && ( pxBlock->pxNextFreeBlock != NULL ) ) | |
| { | |
| pxPreviousBlock = pxBlock; | |
| pxBlock = pxBlock->pxNextFreeBlock; | |
| } | |
| /* If the end marker was reached then a block of adequate size | |
| * was not found. */ | |
| if( pxBlock != pxEnd ) | |
| { | |
| /* Return the memory space pointed to - jumping over the | |
| * BlockLink_t structure at its start. */ | |
| pvReturn = ( void * ) ( ( ( uint8_t * ) pxPreviousBlock->pxNextFreeBlock ) + xHeapStructSize ); | |
| /* This block is being returned for use so must be taken out | |
| * of the list of free blocks. */ | |
| pxPreviousBlock->pxNextFreeBlock = pxBlock->pxNextFreeBlock; | |
| /* If the block is larger than required it can be split into | |
| * two. */ | |
| if( ( pxBlock->xBlockSize - xWantedSize ) > heapMINIMUM_BLOCK_SIZE ) | |
| { | |
| /* This block is to be split into two. Create a new | |
| * block following the number of bytes requested. The void | |
| * cast is used to prevent byte alignment warnings from the | |
| * compiler. */ | |
| pxNewBlockLink = ( void * ) ( ( ( uint8_t * ) pxBlock ) + xWantedSize ); | |
| configASSERT( ( ( ( size_t ) pxNewBlockLink ) & portBYTE_ALIGNMENT_MASK ) == 0 ); | |
| /* Calculate the sizes of two blocks split from the | |
| * single block. */ | |
| pxNewBlockLink->xBlockSize = pxBlock->xBlockSize - xWantedSize; | |
| pxBlock->xBlockSize = xWantedSize; | |
| /* Insert the new block into the list of free blocks. */ | |
| prvInsertBlockIntoFreeList( pxNewBlockLink ); | |
| } | |
| else | |
| { | |
| mtCOVERAGE_TEST_MARKER(); | |
| } | |
| xFreeBytesRemaining -= pxBlock->xBlockSize; | |
| if( xFreeBytesRemaining < xMinimumEverFreeBytesRemaining ) | |
| { | |
| xMinimumEverFreeBytesRemaining = xFreeBytesRemaining; | |
| } | |
| else | |
| { | |
| mtCOVERAGE_TEST_MARKER(); | |
| } | |
| /* The block is being returned - it is allocated and owned | |
| * by the application and has no "next" block. */ | |
| pxBlock->xBlockSize |= xBlockAllocatedBit; | |
| pxBlock->pxNextFreeBlock = NULL; | |
| xNumberOfSuccessfulAllocations++; | |
| } | |
| else | |
| { | |
| mtCOVERAGE_TEST_MARKER(); | |
| } | |
| } | |
| else | |
| { | |
| mtCOVERAGE_TEST_MARKER(); | |
| } | |
| } | |
| else | |
| { | |
| mtCOVERAGE_TEST_MARKER(); | |
| } | |
| traceMALLOC( pvReturn, xWantedSize ); | |
| } | |
| ( void ) xTaskResumeAll(); | |
| #if ( configUSE_MALLOC_FAILED_HOOK == 1 ) | |
| { | |
| if( pvReturn == NULL ) | |
| { | |
| extern void vApplicationMallocFailedHook( void ); | |
| vApplicationMallocFailedHook(); | |
| } | |
| else | |
| { | |
| mtCOVERAGE_TEST_MARKER(); | |
| } | |
| } | |
| #endif /* if ( configUSE_MALLOC_FAILED_HOOK == 1 ) */ | |
| configASSERT( ( ( ( size_t ) pvReturn ) & ( size_t ) portBYTE_ALIGNMENT_MASK ) == 0 ); | |
| return pvReturn; | |
| } | |
| /*-----------------------------------------------------------*/ | |
| void vPortFree( void * pv ) | |
| { | |
| uint8_t * puc = ( uint8_t * ) pv; | |
| BlockLink_t * pxLink; | |
| if( pv != NULL ) | |
| { | |
| /* The memory being freed will have an BlockLink_t structure immediately | |
| * before it. */ | |
| puc -= xHeapStructSize; | |
| /* This casting is to keep the compiler from issuing warnings. */ | |
| pxLink = ( void * ) puc; | |
| /* Check the block is actually allocated. */ | |
| configASSERT( ( pxLink->xBlockSize & xBlockAllocatedBit ) != 0 ); | |
| configASSERT( pxLink->pxNextFreeBlock == NULL ); | |
| if( ( pxLink->xBlockSize & xBlockAllocatedBit ) != 0 ) | |
| { | |
| if( pxLink->pxNextFreeBlock == NULL ) | |
| { | |
| /* The block is being returned to the heap - it is no longer | |
| * allocated. */ | |
| pxLink->xBlockSize &= ~xBlockAllocatedBit; | |
| vTaskSuspendAll(); | |
| { | |
| /* Add this block to the list of free blocks. */ | |
| xFreeBytesRemaining += pxLink->xBlockSize; | |
| traceFREE( pv, pxLink->xBlockSize ); | |
| prvInsertBlockIntoFreeList( ( ( BlockLink_t * ) pxLink ) ); | |
| xNumberOfSuccessfulFrees++; | |
| } | |
| ( void ) xTaskResumeAll(); | |
| } | |
| else | |
| { | |
| mtCOVERAGE_TEST_MARKER(); | |
| } | |
| } | |
| else | |
| { | |
| mtCOVERAGE_TEST_MARKER(); | |
| } | |
| } | |
| } | |
| /*-----------------------------------------------------------*/ | |
| size_t xPortGetFreeHeapSize( void ) | |
| { | |
| return xFreeBytesRemaining; | |
| } | |
| /*-----------------------------------------------------------*/ | |
| size_t xPortGetMinimumEverFreeHeapSize( void ) | |
| { | |
| return xMinimumEverFreeBytesRemaining; | |
| } | |
| /*-----------------------------------------------------------*/ | |
| void vPortInitialiseBlocks( void ) | |
| { | |
| /* This just exists to keep the linker quiet. */ | |
| } | |
| /*-----------------------------------------------------------*/ | |
| static void prvHeapInit( void ) /* PRIVILEGED_FUNCTION */ | |
| { | |
| BlockLink_t * pxFirstFreeBlock; | |
| uint8_t * pucAlignedHeap; | |
| size_t uxAddress; | |
| size_t xTotalHeapSize = configTOTAL_HEAP_SIZE; | |
| /* Ensure the heap starts on a correctly aligned boundary. */ | |
| uxAddress = ( size_t ) ucHeap; | |
| if( ( uxAddress & portBYTE_ALIGNMENT_MASK ) != 0 ) | |
| { | |
| uxAddress += ( portBYTE_ALIGNMENT - 1 ); | |
| uxAddress &= ~( ( size_t ) portBYTE_ALIGNMENT_MASK ); | |
| xTotalHeapSize -= uxAddress - ( size_t ) ucHeap; | |
| } | |
| pucAlignedHeap = ( uint8_t * ) uxAddress; | |
| /* xStart is used to hold a pointer to the first item in the list of free | |
| * blocks. The void cast is used to prevent compiler warnings. */ | |
| xStart.pxNextFreeBlock = ( void * ) pucAlignedHeap; | |
| xStart.xBlockSize = ( size_t ) 0; | |
| /* pxEnd is used to mark the end of the list of free blocks and is inserted | |
| * at the end of the heap space. */ | |
| uxAddress = ( ( size_t ) pucAlignedHeap ) + xTotalHeapSize; | |
| uxAddress -= xHeapStructSize; | |
| uxAddress &= ~( ( size_t ) portBYTE_ALIGNMENT_MASK ); | |
| pxEnd = ( void * ) uxAddress; | |
| pxEnd->xBlockSize = 0; | |
| pxEnd->pxNextFreeBlock = NULL; | |
| /* To start with there is a single free block that is sized to take up the | |
| * entire heap space, minus the space taken by pxEnd. */ | |
| pxFirstFreeBlock = ( void * ) pucAlignedHeap; | |
| pxFirstFreeBlock->xBlockSize = uxAddress - ( size_t ) pxFirstFreeBlock; | |
| pxFirstFreeBlock->pxNextFreeBlock = pxEnd; | |
| /* Only one block exists - and it covers the entire usable heap space. */ | |
| xMinimumEverFreeBytesRemaining = pxFirstFreeBlock->xBlockSize; | |
| xFreeBytesRemaining = pxFirstFreeBlock->xBlockSize; | |
| /* Work out the position of the top bit in a size_t variable. */ | |
| xBlockAllocatedBit = ( ( size_t ) 1 ) << ( ( sizeof( size_t ) * heapBITS_PER_BYTE ) - 1 ); | |
| } | |
| /*-----------------------------------------------------------*/ | |
| static void prvInsertBlockIntoFreeList( BlockLink_t * pxBlockToInsert ) /* PRIVILEGED_FUNCTION */ | |
| { | |
| BlockLink_t * pxIterator; | |
| uint8_t * puc; | |
| /* Iterate through the list until a block is found that has a higher address | |
| * than the block being inserted. */ | |
| for( pxIterator = &xStart; pxIterator->pxNextFreeBlock < pxBlockToInsert; pxIterator = pxIterator->pxNextFreeBlock ) | |
| { | |
| /* Nothing to do here, just iterate to the right position. */ | |
| } | |
| /* Do the block being inserted, and the block it is being inserted after | |
| * make a contiguous block of memory? */ | |
| puc = ( uint8_t * ) pxIterator; | |
| if( ( puc + pxIterator->xBlockSize ) == ( uint8_t * ) pxBlockToInsert ) | |
| { | |
| pxIterator->xBlockSize += pxBlockToInsert->xBlockSize; | |
| pxBlockToInsert = pxIterator; | |
| } | |
| else | |
| { | |
| mtCOVERAGE_TEST_MARKER(); | |
| } | |
| /* Do the block being inserted, and the block it is being inserted before | |
| * make a contiguous block of memory? */ | |
| puc = ( uint8_t * ) pxBlockToInsert; | |
| if( ( puc + pxBlockToInsert->xBlockSize ) == ( uint8_t * ) pxIterator->pxNextFreeBlock ) | |
| { | |
| if( pxIterator->pxNextFreeBlock != pxEnd ) | |
| { | |
| /* Form one big block from the two blocks. */ | |
| pxBlockToInsert->xBlockSize += pxIterator->pxNextFreeBlock->xBlockSize; | |
| pxBlockToInsert->pxNextFreeBlock = pxIterator->pxNextFreeBlock->pxNextFreeBlock; | |
| } | |
| else | |
| { | |
| pxBlockToInsert->pxNextFreeBlock = pxEnd; | |
| } | |
| } | |
| else | |
| { | |
| pxBlockToInsert->pxNextFreeBlock = pxIterator->pxNextFreeBlock; | |
| } | |
| /* If the block being inserted plugged a gab, so was merged with the block | |
| * before and the block after, then it's pxNextFreeBlock pointer will have | |
| * already been set, and should not be set here as that would make it point | |
| * to itself. */ | |
| if( pxIterator != pxBlockToInsert ) | |
| { | |
| pxIterator->pxNextFreeBlock = pxBlockToInsert; | |
| } | |
| else | |
| { | |
| mtCOVERAGE_TEST_MARKER(); | |
| } | |
| } | |
| /*-----------------------------------------------------------*/ | |
| void vPortGetHeapStats( HeapStats_t * pxHeapStats ) | |
| { | |
| BlockLink_t * pxBlock; | |
| size_t xBlocks = 0, xMaxSize = 0, xMinSize = portMAX_DELAY; /* portMAX_DELAY used as a portable way of getting the maximum value. */ | |
| vTaskSuspendAll(); | |
| { | |
| pxBlock = xStart.pxNextFreeBlock; | |
| /* pxBlock will be NULL if the heap has not been initialised. The heap | |
| * is initialised automatically when the first allocation is made. */ | |
| if( pxBlock != NULL ) | |
| { | |
| do | |
| { | |
| /* Increment the number of blocks and record the largest block seen | |
| * so far. */ | |
| xBlocks++; | |
| if( pxBlock->xBlockSize > xMaxSize ) | |
| { | |
| xMaxSize = pxBlock->xBlockSize; | |
| } | |
| if( pxBlock->xBlockSize < xMinSize ) | |
| { | |
| xMinSize = pxBlock->xBlockSize; | |
| } | |
| /* Move to the next block in the chain until the last block is | |
| * reached. */ | |
| pxBlock = pxBlock->pxNextFreeBlock; | |
| } while( pxBlock != pxEnd ); | |
| } | |
| } | |
| ( void ) xTaskResumeAll(); | |
| pxHeapStats->xSizeOfLargestFreeBlockInBytes = xMaxSize; | |
| pxHeapStats->xSizeOfSmallestFreeBlockInBytes = xMinSize; | |
| pxHeapStats->xNumberOfFreeBlocks = xBlocks; | |
| taskENTER_CRITICAL(); | |
| { | |
| pxHeapStats->xAvailableHeapSpaceInBytes = xFreeBytesRemaining; | |
| pxHeapStats->xNumberOfSuccessfulAllocations = xNumberOfSuccessfulAllocations; | |
| pxHeapStats->xNumberOfSuccessfulFrees = xNumberOfSuccessfulFrees; | |
| pxHeapStats->xMinimumEverFreeBytesRemaining = xMinimumEverFreeBytesRemaining; | |
| } | |
| taskEXIT_CRITICAL(); | |
| } |