/*
* FreeRTOS Kernel V10.3.1
* Copyright (C) 2020 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
*
*/
/*
* A sample implementation of pvPortMalloc() that allows the heap to be defined
* across multiple non-contigous blocks and combines (coalescences) adjacent
* memory blocks as they are freed.
*
* See heap_1.c, heap_2.c, heap_3.c and heap_4.c for alternative
* implementations, and the memory management pages of http://www.FreeRTOS.org
* for more information.
*
* Usage notes:
*
* vPortDefineHeapRegions() ***must*** be called before pvPortMalloc().
* pvPortMalloc() will be called if any task objects (tasks, queues, event
* groups, etc.) are created, therefore vPortDefineHeapRegions() ***must*** be
* called before any other objects are defined.
*
* vPortDefineHeapRegions() takes a single parameter. The parameter is an array
* of HeapRegion_t structures. HeapRegion_t is defined in portable.h as
*
* typedef struct HeapRegion
* {
* uint8_t *pucStartAddress; << Start address of a block of memory that will be part of the heap.
* size_t xSizeInBytes; << Size of the block of memory.
* } HeapRegion_t;
*
* The array is terminated using a NULL zero sized region definition, and the
* memory regions defined in the array ***must*** appear in address order from
* low address to high address. So the following is a valid example of how
* to use the function.
*
* HeapRegion_t xHeapRegions[] =
* {
* { ( uint8_t * ) 0x80000000UL, 0x10000 }, << Defines a block of 0x10000 bytes starting at address 0x80000000
* { ( uint8_t * ) 0x90000000UL, 0xa0000 }, << Defines a block of 0xa0000 bytes starting at address of 0x90000000
* { NULL, 0 } << Terminates the array.
* };
*
* vPortDefineHeapRegions( xHeapRegions ); << Pass the array into vPortDefineHeapRegions().
*
* Note 0x80000000 is the lower address so appears in the array first.
*
*/
#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 )
/* 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 );
/*-----------------------------------------------------------*/
/* 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. */
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. */
static size_t xFreeBytesRemaining = 0U;
static size_t xMinimumEverFreeBytesRemaining = 0U;
static size_t xNumberOfSuccessfulAllocations = 0;
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. */
static size_t xBlockAllocatedBit = 0;
/*-----------------------------------------------------------*/
void * pvPortMalloc( size_t xWantedSize )
{
BlockLink_t * pxBlock, * pxPreviousBlock, * pxNewBlockLink;
void * pvReturn = NULL;
/* The heap must be initialised before the first call to
* prvPortMalloc(). */
configASSERT( pxEnd );
vTaskSuspendAll();
{
/* 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 is increased so it can contain a BlockLink_t
* structure in addition to the requested amount of bytes. */
if( xWantedSize > 0 )
{
xWantedSize += xHeapStructSize;
/* Ensure that blocks are always aligned to the required number
* of bytes. */
if( ( xWantedSize & portBYTE_ALIGNMENT_MASK ) != 0x00 )
{
/* Byte alignment required. */
xWantedSize += ( portBYTE_ALIGNMENT - ( xWantedSize & portBYTE_ALIGNMENT_MASK ) );
}
else
{
mtCOVERAGE_TEST_MARKER();
}
}
else
{
mtCOVERAGE_TEST_MARKER();
}
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 );
/* 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 ) */
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;
}
/*-----------------------------------------------------------*/
static void prvInsertBlockIntoFreeList( BlockLink_t * pxBlockToInsert )
{
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 vPortDefineHeapRegions( const HeapRegion_t * const pxHeapRegions )
{
BlockLink_t * pxFirstFreeBlockInRegion = NULL, * pxPreviousFreeBlock;
size_t xAlignedHeap;
size_t xTotalRegionSize, xTotalHeapSize = 0;
BaseType_t xDefinedRegions = 0;
size_t xAddress;
const HeapRegion_t * pxHeapRegion;
/* Can only call once! */
configASSERT( pxEnd == NULL );
pxHeapRegion = &( pxHeapRegions[ xDefinedRegions ] );
while( pxHeapRegion->xSizeInBytes > 0 )
{
xTotalRegionSize = pxHeapRegion->xSizeInBytes;
/* Ensure the heap region starts on a correctly aligned boundary. */
xAddress = ( size_t ) pxHeapRegion->pucStartAddress;
if( ( xAddress & portBYTE_ALIGNMENT_MASK ) != 0 )
{
xAddress += ( portBYTE_ALIGNMENT - 1 );
xAddress &= ~portBYTE_ALIGNMENT_MASK;
/* Adjust the size for the bytes lost to alignment. */
xTotalRegionSize -= xAddress - ( size_t ) pxHeapRegion->pucStartAddress;
}
xAlignedHeap = xAddress;
/* Set xStart if it has not already been set. */
if( xDefinedRegions == 0 )
{
/* 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 = ( BlockLink_t * ) xAlignedHeap;
xStart.xBlockSize = ( size_t ) 0;
}
else
{
/* Should only get here if one region has already been added to the
* heap. */
configASSERT( pxEnd != NULL );
/* Check blocks are passed in with increasing start addresses. */
configASSERT( xAddress > ( size_t ) pxEnd );
}
/* Remember the location of the end marker in the previous region, if
* any. */
pxPreviousFreeBlock = pxEnd;
/* pxEnd is used to mark the end of the list of free blocks and is
* inserted at the end of the region space. */
xAddress = xAlignedHeap + xTotalRegionSize;
xAddress -= xHeapStructSize;
xAddress &= ~portBYTE_ALIGNMENT_MASK;
pxEnd = ( BlockLink_t * ) xAddress;
pxEnd->xBlockSize = 0;
pxEnd->pxNextFreeBlock = NULL;
/* To start with there is a single free block in this region that is
* sized to take up the entire heap region minus the space taken by the
* free block structure. */
pxFirstFreeBlockInRegion = ( BlockLink_t * ) xAlignedHeap;
pxFirstFreeBlockInRegion->xBlockSize = xAddress - ( size_t ) pxFirstFreeBlockInRegion;
pxFirstFreeBlockInRegion->pxNextFreeBlock = pxEnd;
/* If this is not the first region that makes up the entire heap space
* then link the previous region to this region. */
if( pxPreviousFreeBlock != NULL )
{
pxPreviousFreeBlock->pxNextFreeBlock = pxFirstFreeBlockInRegion;
}
xTotalHeapSize += pxFirstFreeBlockInRegion->xBlockSize;
/* Move onto the next HeapRegion_t structure. */
xDefinedRegions++;
pxHeapRegion = &( pxHeapRegions[ xDefinedRegions ] );
}
xMinimumEverFreeBytesRemaining = xTotalHeapSize;
xFreeBytesRemaining = xTotalHeapSize;
/* Check something was actually defined before it is accessed. */
configASSERT( xTotalHeapSize );
/* Work out the position of the top bit in a size_t variable. */
xBlockAllocatedBit = ( ( size_t ) 1 ) << ( ( sizeof( size_t ) * heapBITS_PER_BYTE ) - 1 );
}
/*-----------------------------------------------------------*/
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;
}
/* Heap five will have a zero sized block at the end of each
* each region - the block is only used to link to the next
* heap region so it not a real block. */
if( pxBlock->xBlockSize != 0 )
{
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();
}