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Enhance heap_4.c to prevent blocks accidentally being freed twice, or blocks that don't have a valid block link descriptor being freed.
Update the Cortex-A9 port to include asserts if an ISR safe FreeRTOS function is called from an interrupt that has a higher logical priority than configMAX_SYSCALL_INTERRUPT_PRIORITY (or whatever the CA9 equivalent is called), and also assert if the binary point is not set correctly.
This commit is contained in:
Richard Barry
parent
4894955a08
commit
0f6b0d3a59
5 changed files with 371 additions and 200 deletions
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@ -95,8 +95,11 @@ task.h is included from an application file. */
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/* Block sizes must not get too small. */
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#define heapMINIMUM_BLOCK_SIZE ( ( size_t ) ( heapSTRUCT_SIZE * 2 ) )
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/* Assumes 8bit bytes! */
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#define heapBITS_PER_BYTE ( ( size_t ) 8 )
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/* A few bytes might be lost to byte aligning the heap start address. */
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#define configADJUSTED_HEAP_SIZE ( configTOTAL_HEAP_SIZE - portBYTE_ALIGNMENT )
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#define heapADJUSTED_HEAP_SIZE ( configTOTAL_HEAP_SIZE - portBYTE_ALIGNMENT )
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/* Allocate the memory for the heap. */
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static unsigned char ucHeap[ configTOTAL_HEAP_SIZE ];
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@ -132,16 +135,20 @@ block must by correctly byte aligned. */
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static const unsigned short heapSTRUCT_SIZE = ( ( sizeof ( xBlockLink ) + ( portBYTE_ALIGNMENT - 1 ) ) & ~portBYTE_ALIGNMENT_MASK );
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/* Ensure the pxEnd pointer will end up on the correct byte alignment. */
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static const size_t xTotalHeapSize = ( ( size_t ) configADJUSTED_HEAP_SIZE ) & ( ( size_t ) ~portBYTE_ALIGNMENT_MASK );
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static const size_t xTotalHeapSize = ( ( size_t ) heapADJUSTED_HEAP_SIZE ) & ( ( size_t ) ~portBYTE_ALIGNMENT_MASK );
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/* Create a couple of list links to mark the start and end of the list. */
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static xBlockLink xStart, *pxEnd = NULL;
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/* Keeps track of the number of free bytes remaining, but says nothing about
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fragmentation. */
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static size_t xFreeBytesRemaining = ( ( size_t ) configADJUSTED_HEAP_SIZE ) & ( ( size_t ) ~portBYTE_ALIGNMENT_MASK );
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static size_t xFreeBytesRemaining = ( ( size_t ) heapADJUSTED_HEAP_SIZE ) & ( ( size_t ) ~portBYTE_ALIGNMENT_MASK );
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/* STATIC FUNCTIONS ARE DEFINED AS MACROS TO MINIMIZE THE FUNCTION CALL DEPTH. */
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/* Gets set to the top bit of an size_t type. When this bit in the xBlockSize
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member of an xBlockLink structure is set then the block belongs to the
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application. When the bit is free the block is still part of the free heap
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space. */
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static size_t xBlockAllocatedBit = 0;
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/*-----------------------------------------------------------*/
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@ -159,63 +166,77 @@ void *pvReturn = NULL;
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prvHeapInit();
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}
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/* The wanted size is increased so it can contain a xBlockLink
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structure in addition to the requested amount of bytes. */
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if( xWantedSize > 0 )
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/* Check the requested block size is not so large that the top bit is
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set. The top bit of the block size member of the xBlockLink structure
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is used to determine who owns the block - the application or the
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kernel, so it must be free. */
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if( ( xWantedSize & xBlockAllocatedBit ) == 0 )
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{
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xWantedSize += heapSTRUCT_SIZE;
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/* Ensure that blocks are always aligned to the required number of
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bytes. */
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if( ( xWantedSize & portBYTE_ALIGNMENT_MASK ) != 0x00 )
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/* The wanted size is increased so it can contain a xBlockLink
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structure in addition to the requested amount of bytes. */
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if( xWantedSize > 0 )
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{
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/* Byte alignment required. */
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xWantedSize += ( portBYTE_ALIGNMENT - ( xWantedSize & portBYTE_ALIGNMENT_MASK ) );
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}
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}
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xWantedSize += heapSTRUCT_SIZE;
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if( ( xWantedSize > 0 ) && ( xWantedSize < xTotalHeapSize ) )
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{
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/* Traverse the list from the start (lowest address) block until one
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of adequate size is found. */
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pxPreviousBlock = &xStart;
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pxBlock = xStart.pxNextFreeBlock;
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while( ( pxBlock->xBlockSize < xWantedSize ) && ( pxBlock->pxNextFreeBlock != NULL ) )
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{
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pxPreviousBlock = pxBlock;
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pxBlock = pxBlock->pxNextFreeBlock;
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}
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/* If the end marker was reached then a block of adequate size was
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not found. */
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if( pxBlock != pxEnd )
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{
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/* Return the memory space - jumping over the xBlockLink structure
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at its start. */
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pvReturn = ( void * ) ( ( ( unsigned char * ) pxPreviousBlock->pxNextFreeBlock ) + heapSTRUCT_SIZE );
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/* This block is being returned for use so must be taken out of
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the list of free blocks. */
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pxPreviousBlock->pxNextFreeBlock = pxBlock->pxNextFreeBlock;
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/* If the block is larger than required it can be split into two. */
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if( ( pxBlock->xBlockSize - xWantedSize ) > heapMINIMUM_BLOCK_SIZE )
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/* Ensure that blocks are always aligned to the required number
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of bytes. */
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if( ( xWantedSize & portBYTE_ALIGNMENT_MASK ) != 0x00 )
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{
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/* This block is to be split into two. Create a new block
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following the number of bytes requested. The void cast is
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used to prevent byte alignment warnings from the compiler. */
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pxNewBlockLink = ( void * ) ( ( ( unsigned char * ) pxBlock ) + xWantedSize );
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/* Byte alignment required. */
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xWantedSize += ( portBYTE_ALIGNMENT - ( xWantedSize & portBYTE_ALIGNMENT_MASK ) );
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}
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}
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/* Calculate the sizes of two blocks split from the single
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block. */
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pxNewBlockLink->xBlockSize = pxBlock->xBlockSize - xWantedSize;
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pxBlock->xBlockSize = xWantedSize;
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/* Insert the new block into the list of free blocks. */
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prvInsertBlockIntoFreeList( ( pxNewBlockLink ) );
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if( ( xWantedSize > 0 ) && ( xWantedSize <= xFreeBytesRemaining ) )
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{
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/* Traverse the list from the start (lowest address) block until
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one of adequate size is found. */
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pxPreviousBlock = &xStart;
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pxBlock = xStart.pxNextFreeBlock;
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while( ( pxBlock->xBlockSize < xWantedSize ) && ( pxBlock->pxNextFreeBlock != NULL ) )
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{
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pxPreviousBlock = pxBlock;
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pxBlock = pxBlock->pxNextFreeBlock;
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}
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xFreeBytesRemaining -= pxBlock->xBlockSize;
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/* If the end marker was reached then a block of adequate size
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was not found. */
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if( pxBlock != pxEnd )
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{
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/* Return the memory space pointed to - jumping over the
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xBlockLink structure at its start. */
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pvReturn = ( void * ) ( ( ( unsigned char * ) pxPreviousBlock->pxNextFreeBlock ) + heapSTRUCT_SIZE );
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/* This block is being returned for use so must be taken out
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of the list of free blocks. */
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pxPreviousBlock->pxNextFreeBlock = pxBlock->pxNextFreeBlock;
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/* If the block is larger than required it can be split into
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two. */
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if( ( pxBlock->xBlockSize - xWantedSize ) > heapMINIMUM_BLOCK_SIZE )
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{
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/* This block is to be split into two. Create a new
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block following the number of bytes requested. The void
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cast is used to prevent byte alignment warnings from the
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compiler. */
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pxNewBlockLink = ( void * ) ( ( ( unsigned char * ) pxBlock ) + xWantedSize );
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/* Calculate the sizes of two blocks split from the
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single block. */
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pxNewBlockLink->xBlockSize = pxBlock->xBlockSize - xWantedSize;
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pxBlock->xBlockSize = xWantedSize;
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/* Insert the new block into the list of free blocks. */
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prvInsertBlockIntoFreeList( ( pxNewBlockLink ) );
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}
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xFreeBytesRemaining -= pxBlock->xBlockSize;
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/* The block is being returned - it is allocated and owned
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by the application and has no "next" block. */
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pxBlock->xBlockSize |= xBlockAllocatedBit;
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pxBlock->pxNextFreeBlock = NULL;
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}
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}
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}
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}
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@ -249,13 +270,27 @@ xBlockLink *pxLink;
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/* This casting is to keep the compiler from issuing warnings. */
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pxLink = ( void * ) puc;
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vTaskSuspendAll();
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/* Check the block is actually allocated. */
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configASSERT( ( pxLink->xBlockSize & xBlockAllocatedBit ) != 0 );
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configASSERT( pxLink->pxNextFreeBlock == NULL );
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if( ( pxLink->xBlockSize & xBlockAllocatedBit ) != 0 )
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{
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/* Add this block to the list of free blocks. */
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xFreeBytesRemaining += pxLink->xBlockSize;
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prvInsertBlockIntoFreeList( ( ( xBlockLink * ) pxLink ) );
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if( pxLink->pxNextFreeBlock == NULL )
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{
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/* The block is being returned to the heap - it is no longer
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allocated. */
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pxLink->xBlockSize &= ~xBlockAllocatedBit;
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vTaskSuspendAll();
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{
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/* Add this block to the list of free blocks. */
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xFreeBytesRemaining += pxLink->xBlockSize;
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prvInsertBlockIntoFreeList( ( ( xBlockLink * ) pxLink ) );
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}
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xTaskResumeAll();
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}
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}
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xTaskResumeAll();
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}
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}
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/*-----------------------------------------------------------*/
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@ -302,6 +337,9 @@ unsigned char *pucHeapEnd, *pucAlignedHeap;
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/* The heap now contains pxEnd. */
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xFreeBytesRemaining -= heapSTRUCT_SIZE;
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/* Work out the position of the top bit in a size_t variable. */
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xBlockAllocatedBit = ( ( size_t ) 1 ) << ( ( sizeof( size_t ) * heapBITS_PER_BYTE ) - 1 );
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}
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/*-----------------------------------------------------------*/
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