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Diffstat (limited to 'cpukit/score/include/rtems/score/heap.h')
-rw-r--r-- | cpukit/score/include/rtems/score/heap.h | 518 |
1 files changed, 0 insertions, 518 deletions
diff --git a/cpukit/score/include/rtems/score/heap.h b/cpukit/score/include/rtems/score/heap.h deleted file mode 100644 index 60cb3be99d..0000000000 --- a/cpukit/score/include/rtems/score/heap.h +++ /dev/null @@ -1,518 +0,0 @@ -/** - * @file - * - * @ingroup ScoreHeap - * - * @brief Heap Handler API - */ - -/* - * COPYRIGHT (c) 1989-2006. - * On-Line Applications Research Corporation (OAR). - * - * The license and distribution terms for this file may be - * found in the file LICENSE in this distribution or at - * http://www.rtems.org/license/LICENSE. - */ - -#ifndef _RTEMS_SCORE_HEAP_H -#define _RTEMS_SCORE_HEAP_H - -#include <rtems/score/cpu.h> -#include <rtems/score/thread.h> - -#ifdef __cplusplus -extern "C" { -#endif - -#ifdef RTEMS_DEBUG - #define HEAP_PROTECTION -#endif - -/** - * @defgroup ScoreHeap Heap Handler - * - * @ingroup Score - * - * @brief The Heap Handler provides a heap. - * - * A heap is a doubly linked list of variable size blocks which are allocated - * using the first fit method. Garbage collection is performed each time a - * block is returned to the heap by coalescing neighbor blocks. Control - * information for both allocated and free blocks is contained in the heap - * area. A heap control structure contains control information for the heap. - * - * The alignment routines could be made faster should we require only powers of - * two to be supported for page size, alignment and boundary arguments. The - * minimum alignment requirement for pages is currently CPU_ALIGNMENT and this - * value is only required to be multiple of two and explicitly not required to - * be a power of two. - * - * There are two kinds of blocks. One sort describes a free block from which - * we can allocate memory. The other blocks are used and provide an allocated - * memory area. The free blocks are accessible via a list of free blocks. - * - * Blocks or areas cover a continuous set of memory addresses. They have a - * begin and end address. The end address is not part of the set. The size of - * a block or area equals the distance between the begin and end address in - * units of bytes. - * - * Free blocks look like: - * <table> - * <tr> - * <td rowspan=4>@ref Heap_Block</td><td>previous block size in case the - * previous block is free, <br> otherwise it may contain data used by - * the previous block</td> - * </tr> - * <tr> - * <td>block size and a flag which indicates if the previous block is free - * or used, <br> this field contains always valid data regardless of the - * block usage</td> - * </tr> - * <tr><td>pointer to next block (this field is page size aligned)</td></tr> - * <tr><td>pointer to previous block</td></tr> - * <tr><td colspan=2>free space</td></tr> - * </table> - * - * Used blocks look like: - * <table> - * <tr> - * <td rowspan=4>@ref Heap_Block</td><td>previous block size in case the - * previous block is free,<br>otherwise it may contain data used by - * the previous block</td> - * </tr> - * <tr> - * <td>block size and a flag which indicates if the previous block is free - * or used, <br> this field contains always valid data regardless of the - * block usage</td> - * </tr> - * <tr><td>begin of allocated area (this field is page size aligned)</td></tr> - * <tr><td>allocated space</td></tr> - * <tr><td colspan=2>allocated space</td></tr> - * </table> - * - * The heap area after initialization contains two blocks and looks like: - * <table> - * <tr><th>Label</th><th colspan=2>Content</th></tr> - * <tr><td>heap->area_begin</td><td colspan=2>heap area begin address</td></tr> - * <tr> - * <td>first_block->prev_size</td> - * <td colspan=2> - * subordinate heap area end address (this will be used to maintain a - * linked list of scattered heap areas) - * </td> - * </tr> - * <tr> - * <td>first_block->size</td> - * <td colspan=2>size available for allocation - * | @c HEAP_PREV_BLOCK_USED</td> - * </tr> - * <tr> - * <td>first_block->next</td><td>_Heap_Free_list_tail(heap)</td> - * <td rowspan=3>memory area available for allocation</td> - * </tr> - * <tr><td>first_block->prev</td><td>_Heap_Free_list_head(heap)</td></tr> - * <tr><td>...</td></tr> - * <tr> - * <td>last_block->prev_size</td><td colspan=2>size of first block</td> - * </tr> - * <tr> - * <td>last_block->size</td> - * <td colspan=2>first block begin address - last block begin address</td> - * </tr> - * <tr><td>heap->area_end</td><td colspan=2>heap area end address</td></tr> - * </table> - * The next block of the last block is the first block. Since the first - * block indicates that the previous block is used, this ensures that the - * last block appears as used for the _Heap_Is_used() and _Heap_Is_free() - * functions. - */ -/**@{**/ - -typedef struct Heap_Control Heap_Control; - -typedef struct Heap_Block Heap_Block; - -#ifndef HEAP_PROTECTION - #define HEAP_PROTECTION_HEADER_SIZE 0 -#else - #define HEAP_PROTECTOR_COUNT 2 - - #define HEAP_BEGIN_PROTECTOR_0 ((uintptr_t) 0xfd75a98f) - #define HEAP_BEGIN_PROTECTOR_1 ((uintptr_t) 0xbfa1f177) - #define HEAP_END_PROTECTOR_0 ((uintptr_t) 0xd6b8855e) - #define HEAP_END_PROTECTOR_1 ((uintptr_t) 0x13a44a5b) - - #define HEAP_FREE_PATTERN ((uintptr_t) 0xe7093cdf) - - #define HEAP_PROTECTION_OBOLUS ((Heap_Block *) 1) - - typedef void (*_Heap_Protection_handler)( - Heap_Control *heap, - Heap_Block *block - ); - - typedef struct { - _Heap_Protection_handler block_initialize; - _Heap_Protection_handler block_check; - _Heap_Protection_handler block_error; - void *handler_data; - Heap_Block *first_delayed_free_block; - Heap_Block *last_delayed_free_block; - uintptr_t delayed_free_block_count; - uintptr_t delayed_free_fraction; - } Heap_Protection; - - typedef struct { - uintptr_t protector [HEAP_PROTECTOR_COUNT]; - Heap_Block *next_delayed_free_block; - Thread_Control *task; - void *tag; - } Heap_Protection_block_begin; - - typedef struct { - uintptr_t protector [HEAP_PROTECTOR_COUNT]; - } Heap_Protection_block_end; - - #define HEAP_PROTECTION_HEADER_SIZE \ - (sizeof(Heap_Protection_block_begin) + sizeof(Heap_Protection_block_end)) -#endif - -/** - * @brief The block header consists of the two size fields - * (@ref Heap_Block.prev_size and @ref Heap_Block.size_and_flag). - */ -#define HEAP_BLOCK_HEADER_SIZE \ - (2 * sizeof(uintptr_t) + HEAP_PROTECTION_HEADER_SIZE) - -/** - * @brief Description for free or used blocks. - */ -struct Heap_Block { - /** - * @brief Size of the previous block or part of the allocated area of the - * previous block. - * - * This field is only valid if the previous block is free. This case is - * indicated by a cleared @c HEAP_PREV_BLOCK_USED flag in the - * @a size_and_flag field of the current block. - * - * In a used block only the @a size_and_flag field needs to be valid. The - * @a prev_size field of the current block is maintained by the previous - * block. The current block can use the @a prev_size field in the next block - * for allocation. - */ - uintptr_t prev_size; - - #ifdef HEAP_PROTECTION - Heap_Protection_block_begin Protection_begin; - #endif - - /** - * @brief Contains the size of the current block and a flag which indicates - * if the previous block is free or used. - * - * If the flag @c HEAP_PREV_BLOCK_USED is set, then the previous block is - * used, otherwise the previous block is free. A used previous block may - * claim the @a prev_size field for allocation. This trick allows to - * decrease the overhead in the used blocks by the size of the @a prev_size - * field. As sizes are required to be multiples of two, the least - * significant bits would be always zero. We use this bit to store the flag. - * - * This field is always valid. - */ - uintptr_t size_and_flag; - - #ifdef HEAP_PROTECTION - Heap_Protection_block_end Protection_end; - #endif - - /** - * @brief Pointer to the next free block or part of the allocated area. - * - * This field is page size aligned and begins of the allocated area in case - * the block is used. - * - * This field is only valid if the block is free and thus part of the free - * block list. - */ - Heap_Block *next; - - /** - * @brief Pointer to the previous free block or part of the allocated area. - * - * This field is only valid if the block is free and thus part of the free - * block list. - */ - Heap_Block *prev; -}; - -/** - * @brief Run-time heap statistics. - * - * The value @a searches / @a allocs gives the mean number of searches per - * allocation, while @a max_search gives maximum number of searches ever - * performed on a single allocation call. - */ -typedef struct { - /** - * @brief Lifetime number of bytes allocated from this heap. - * - * This value is an integral multiple of the page size. - */ - uint64_t lifetime_allocated; - - /** - * @brief Lifetime number of bytes freed to this heap. - * - * This value is an integral multiple of the page size. - */ - uint64_t lifetime_freed; - - /** - * @brief Size of the allocatable area in bytes. - * - * This value is an integral multiple of the page size. - */ - uintptr_t size; - - /** - * @brief Current free size in bytes. - * - * This value is an integral multiple of the page size. - */ - uintptr_t free_size; - - /** - * @brief Minimum free size ever in bytes. - * - * This value is an integral multiple of the page size. - */ - uintptr_t min_free_size; - - /** - * @brief Current number of free blocks. - */ - uint32_t free_blocks; - - /** - * @brief Maximum number of free blocks ever. - */ - uint32_t max_free_blocks; - - /** - * @brief Current number of used blocks. - */ - uint32_t used_blocks; - - /** - * @brief Maximum number of blocks searched ever. - */ - uint32_t max_search; - - /** - * @brief Total number of searches. - */ - uint32_t searches; - - /** - * @brief Total number of successful allocations. - */ - uint32_t allocs; - - /** - * @brief Total number of failed allocations. - */ - uint32_t failed_allocs; - - /** - * @brief Total number of successful frees. - */ - uint32_t frees; - - /** - * @brief Total number of successful resizes. - */ - uint32_t resizes; -} Heap_Statistics; - -/** - * @brief Control block used to manage a heap. - */ -struct Heap_Control { - Heap_Block free_list; - uintptr_t page_size; - uintptr_t min_block_size; - uintptr_t area_begin; - uintptr_t area_end; - Heap_Block *first_block; - Heap_Block *last_block; - Heap_Statistics stats; - #ifdef HEAP_PROTECTION - Heap_Protection Protection; - #endif -}; - -/** - * @brief Information about blocks. - */ -typedef struct { - /** - * @brief Number of blocks of this type. - */ - uintptr_t number; - - /** - * @brief Largest block of this type. - */ - uintptr_t largest; - - /** - * @brief Total size of the blocks of this type. - */ - uintptr_t total; -} Heap_Information; - -/** - * @brief Information block returned by _Heap_Get_information(). - */ -typedef struct { - Heap_Information Free; - Heap_Information Used; - Heap_Statistics Stats; -} Heap_Information_block; - -/** - * @brief Heap area structure for table based heap initialization and - * extension. - * - * @see Heap_Initialization_or_extend_handler. - */ -typedef struct { - void *begin; - uintptr_t size; -} Heap_Area; - -/** - * @brief Heap initialization and extend handler type. - * - * This helps to do a table based heap initialization and extension. Create a - * table of Heap_Area elements and iterate through it. Set the handler to - * _Heap_Initialize() in the first iteration and then to _Heap_Extend(). - * - * @see Heap_Area, _Heap_Initialize(), _Heap_Extend(), or _Heap_No_extend(). - */ -typedef uintptr_t (*Heap_Initialization_or_extend_handler)( - Heap_Control *heap, - void *area_begin, - uintptr_t area_size, - uintptr_t page_size_or_unused -); - -/** - * @brief Extends the memory available for the heap @a heap using the memory - * area starting at @a area_begin of size @a area_size bytes. - * - * There are no alignment requirements for the memory area. The memory area - * must be big enough to contain some maintenance blocks. It must not overlap - * parts of the current heap memory areas. Disconnected memory areas added to - * the heap will lead to used blocks which cover the gaps. Extending with an - * inappropriate memory area will corrupt the heap resulting in undefined - * behaviour. - * - * The unused fourth parameter is provided to have the same signature as - * _Heap_Initialize(). - * - * Returns the extended space available for allocation, or zero in case of failure. - * - * @see Heap_Initialization_or_extend_handler. - */ -uintptr_t _Heap_Extend( - Heap_Control *heap, - void *area_begin, - uintptr_t area_size, - uintptr_t unused -); - -/** - * @brief This function returns always zero. - * - * This function only returns zero and does nothing else. - * - * Returns always zero. - * - * @see Heap_Initialization_or_extend_handler. - */ -uintptr_t _Heap_No_extend( - Heap_Control *unused_0, - void *unused_1, - uintptr_t unused_2, - uintptr_t unused_3 -); - -RTEMS_INLINE_ROUTINE uintptr_t _Heap_Align_up( - uintptr_t value, - uintptr_t alignment -) -{ - uintptr_t remainder = value % alignment; - - if ( remainder != 0 ) { - return value - remainder + alignment; - } else { - return value; - } -} - -RTEMS_INLINE_ROUTINE uintptr_t _Heap_Min_block_size( uintptr_t page_size ) -{ - return _Heap_Align_up( sizeof( Heap_Block ), page_size ); -} - -/** - * @brief Returns the worst case overhead to manage a memory area. - */ -RTEMS_INLINE_ROUTINE uintptr_t _Heap_Area_overhead( - uintptr_t page_size -) -{ - if ( page_size != 0 ) { - page_size = _Heap_Align_up( page_size, CPU_ALIGNMENT ); - } else { - page_size = CPU_ALIGNMENT; - } - - return 2 * (page_size - 1) + HEAP_BLOCK_HEADER_SIZE; -} - -/** - * @brief Returns the size with administration and alignment overhead for one - * allocation. - */ -RTEMS_INLINE_ROUTINE uintptr_t _Heap_Size_with_overhead( - uintptr_t page_size, - uintptr_t size, - uintptr_t alignment -) -{ - if ( page_size != 0 ) { - page_size = _Heap_Align_up( page_size, CPU_ALIGNMENT ); - } else { - page_size = CPU_ALIGNMENT; - } - - if ( page_size < alignment ) { - page_size = alignment; - } - - return HEAP_BLOCK_HEADER_SIZE + page_size - 1 + size; -} - -/** @} */ - -#ifdef __cplusplus -} -#endif - -#endif -/* end of include file */ |