mirror of
https://bitbucket.org/librepilot/librepilot.git
synced 2024-12-04 12:24:11 +01:00
d2c0dea556
git-svn-id: svn://svn.openpilot.org/OpenPilot/trunk@91 ebee16cc-31ac-478f-84a7-5cbb03baadba
281 lines
11 KiB
C
281 lines
11 KiB
C
/*
|
|
FreeRTOS V6.0.0 - Copyright (C) 2009 Real Time Engineers Ltd.
|
|
|
|
***************************************************************************
|
|
* *
|
|
* If you are: *
|
|
* *
|
|
* + New to FreeRTOS, *
|
|
* + Wanting to learn FreeRTOS or multitasking in general quickly *
|
|
* + Looking for basic training, *
|
|
* + Wanting to improve your FreeRTOS skills and productivity *
|
|
* *
|
|
* then take a look at the FreeRTOS eBook *
|
|
* *
|
|
* "Using the FreeRTOS Real Time Kernel - a Practical Guide" *
|
|
* http://www.FreeRTOS.org/Documentation *
|
|
* *
|
|
* A pdf reference manual is also available. Both are usually delivered *
|
|
* to your inbox within 20 minutes to two hours when purchased between 8am *
|
|
* and 8pm GMT (although please allow up to 24 hours in case of *
|
|
* exceptional circumstances). Thank you for your support! *
|
|
* *
|
|
***************************************************************************
|
|
|
|
This file is part of the FreeRTOS distribution.
|
|
|
|
FreeRTOS is free software; you can redistribute it and/or modify it under
|
|
the terms of the GNU General Public License (version 2) as published by the
|
|
Free Software Foundation AND MODIFIED BY the FreeRTOS exception.
|
|
***NOTE*** The exception to the GPL is included to allow you to distribute
|
|
a combined work that includes FreeRTOS without being obliged to provide the
|
|
source code for proprietary components outside of the FreeRTOS kernel.
|
|
FreeRTOS is distributed in the hope that it will be useful, but WITHOUT
|
|
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
|
|
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
|
|
more details. You should have received a copy of the GNU General Public
|
|
License and the FreeRTOS license exception along with FreeRTOS; if not it
|
|
can be viewed here: http://www.freertos.org/a00114.html and also obtained
|
|
by writing to Richard Barry, contact details for whom are available on the
|
|
FreeRTOS WEB site.
|
|
|
|
1 tab == 4 spaces!
|
|
|
|
http://www.FreeRTOS.org - Documentation, latest information, license and
|
|
contact details.
|
|
|
|
http://www.SafeRTOS.com - A version that is certified for use in safety
|
|
critical systems.
|
|
|
|
http://www.OpenRTOS.com - Commercial support, development, porting,
|
|
licensing and training services.
|
|
*/
|
|
|
|
/*
|
|
* A sample implementation of pvPortMalloc() and vPortFree() that permits
|
|
* allocated blocks to be freed, but does not combine adjacent free blocks
|
|
* into a single larger block.
|
|
*
|
|
* See heap_1.c and heap_3.c for alternative implementations, and the memory
|
|
* management pages of http://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
|
|
|
|
/* Allocate the memory for the heap. The struct is used to force byte
|
|
alignment without using any non-portable code. */
|
|
static union xRTOS_HEAP
|
|
{
|
|
#if portBYTE_ALIGNMENT == 8
|
|
volatile portDOUBLE dDummy;
|
|
#else
|
|
volatile unsigned long ulDummy;
|
|
#endif
|
|
unsigned char ucHeap[ configTOTAL_HEAP_SIZE ];
|
|
} xHeap;
|
|
|
|
/* Define the linked list structure. This is used to link free blocks in order
|
|
of their size. */
|
|
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. */
|
|
} xBlockLink;
|
|
|
|
|
|
static const unsigned short heapSTRUCT_SIZE = ( sizeof( xBlockLink ) + portBYTE_ALIGNMENT - ( sizeof( xBlockLink ) % portBYTE_ALIGNMENT ) );
|
|
#define heapMINIMUM_BLOCK_SIZE ( ( size_t ) ( heapSTRUCT_SIZE * 2 ) )
|
|
|
|
/* Create a couple of list links to mark the start and end of the list. */
|
|
static xBlockLink xStart, xEnd;
|
|
|
|
/* Keeps track of the number of free bytes remaining, but says nothing about
|
|
fragmentation. */
|
|
static size_t xFreeBytesRemaining;
|
|
|
|
/* STATIC FUNCTIONS ARE DEFINED AS MACROS TO MINIMIZE THE FUNCTION CALL DEPTH. */
|
|
|
|
/*
|
|
* Insert a block into the list of free blocks - which is ordered by size of
|
|
* the block. Small blocks at the start of the list and large blocks at the end
|
|
* of the list.
|
|
*/
|
|
#define prvInsertBlockIntoFreeList( pxBlockToInsert ) \
|
|
{ \
|
|
xBlockLink *pxIterator; \
|
|
size_t xBlockSize; \
|
|
\
|
|
xBlockSize = pxBlockToInsert->xBlockSize; \
|
|
\
|
|
/* Iterate through the list until a block is found that has a larger size */ \
|
|
/* than the block we are inserting. */ \
|
|
for( pxIterator = &xStart; pxIterator->pxNextFreeBlock->xBlockSize < xBlockSize; pxIterator = pxIterator->pxNextFreeBlock ) \
|
|
{ \
|
|
/* There is nothing to do here - just iterate to the correct position. */ \
|
|
} \
|
|
\
|
|
/* Update the list to include the block being inserted in the correct */ \
|
|
/* position. */ \
|
|
pxBlockToInsert->pxNextFreeBlock = pxIterator->pxNextFreeBlock; \
|
|
pxIterator->pxNextFreeBlock = pxBlockToInsert; \
|
|
}
|
|
/*-----------------------------------------------------------*/
|
|
|
|
#define prvHeapInit() \
|
|
{ \
|
|
xBlockLink *pxFirstFreeBlock; \
|
|
\
|
|
/* 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 * ) xHeap.ucHeap; \
|
|
xStart.xBlockSize = ( size_t ) 0; \
|
|
\
|
|
/* xEnd is used to mark the end of the list of free blocks. */ \
|
|
xEnd.xBlockSize = configTOTAL_HEAP_SIZE; \
|
|
xEnd.pxNextFreeBlock = NULL; \
|
|
\
|
|
/* To start with there is a single free block that is sized to take up the \
|
|
entire heap space. */ \
|
|
pxFirstFreeBlock = ( void * ) xHeap.ucHeap; \
|
|
pxFirstFreeBlock->xBlockSize = configTOTAL_HEAP_SIZE; \
|
|
pxFirstFreeBlock->pxNextFreeBlock = &xEnd; \
|
|
\
|
|
xFreeBytesRemaining = configTOTAL_HEAP_SIZE; \
|
|
}
|
|
/*-----------------------------------------------------------*/
|
|
|
|
void *pvPortMalloc( size_t xWantedSize )
|
|
{
|
|
xBlockLink *pxBlock, *pxPreviousBlock, *pxNewBlockLink;
|
|
static portBASE_TYPE xHeapHasBeenInitialised = pdFALSE;
|
|
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( xHeapHasBeenInitialised == pdFALSE )
|
|
{
|
|
prvHeapInit();
|
|
xHeapHasBeenInitialised = pdTRUE;
|
|
}
|
|
|
|
/* The wanted size is increased so it can contain a xBlockLink
|
|
structure in addition to the requested amount of bytes. */
|
|
if( xWantedSize > 0 )
|
|
{
|
|
xWantedSize += heapSTRUCT_SIZE;
|
|
|
|
/* Ensure that blocks are always aligned to the required number of bytes. */
|
|
if( xWantedSize & portBYTE_ALIGNMENT_MASK )
|
|
{
|
|
/* Byte alignment required. */
|
|
xWantedSize += ( portBYTE_ALIGNMENT - ( xWantedSize & portBYTE_ALIGNMENT_MASK ) );
|
|
}
|
|
}
|
|
|
|
if( ( xWantedSize > 0 ) && ( xWantedSize < configTOTAL_HEAP_SIZE ) )
|
|
{
|
|
/* Blocks are stored in byte order - traverse the list from the start
|
|
(smallest) block until one of adequate size is found. */
|
|
pxPreviousBlock = &xStart;
|
|
pxBlock = xStart.pxNextFreeBlock;
|
|
while( ( pxBlock->xBlockSize < xWantedSize ) && ( pxBlock->pxNextFreeBlock ) )
|
|
{
|
|
pxPreviousBlock = pxBlock;
|
|
pxBlock = pxBlock->pxNextFreeBlock;
|
|
}
|
|
|
|
/* If we found the end marker then a block of adequate size was not found. */
|
|
if( pxBlock != &xEnd )
|
|
{
|
|
/* Return the memory space - jumping over the xBlockLink structure
|
|
at its start. */
|
|
pvReturn = ( void * ) ( ( ( unsigned char * ) pxPreviousBlock->pxNextFreeBlock ) + heapSTRUCT_SIZE );
|
|
|
|
/* This block is being returned for use so must be taken our 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 * ) ( ( ( unsigned char * ) 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 ) );
|
|
}
|
|
|
|
xFreeBytesRemaining -= xWantedSize;
|
|
}
|
|
}
|
|
}
|
|
xTaskResumeAll();
|
|
|
|
#if( configUSE_MALLOC_FAILED_HOOK == 1 )
|
|
{
|
|
if( pvReturn == NULL )
|
|
{
|
|
extern void vApplicationMallocFailedHook( void );
|
|
vApplicationMallocFailedHook();
|
|
}
|
|
}
|
|
#endif
|
|
|
|
return pvReturn;
|
|
}
|
|
/*-----------------------------------------------------------*/
|
|
|
|
void vPortFree( void *pv )
|
|
{
|
|
unsigned char *puc = ( unsigned char * ) pv;
|
|
xBlockLink *pxLink;
|
|
|
|
if( pv )
|
|
{
|
|
/* The memory being freed will have an xBlockLink structure immediately
|
|
before it. */
|
|
puc -= heapSTRUCT_SIZE;
|
|
|
|
/* This casting is to keep the compiler from issuing warnings. */
|
|
pxLink = ( void * ) puc;
|
|
|
|
vTaskSuspendAll();
|
|
{
|
|
/* Add this block to the list of free blocks. */
|
|
prvInsertBlockIntoFreeList( ( ( xBlockLink * ) pxLink ) );
|
|
xFreeBytesRemaining += pxLink->xBlockSize;
|
|
}
|
|
xTaskResumeAll();
|
|
}
|
|
}
|
|
/*-----------------------------------------------------------*/
|
|
|
|
size_t xPortGetFreeHeapSize( void )
|
|
{
|
|
return xFreeBytesRemaining;
|
|
}
|
|
/*-----------------------------------------------------------*/
|
|
|
|
void vPortInitialiseBlocks( void )
|
|
{
|
|
/* This just exists to keep the linker quiet. */
|
|
}
|