7 /*#define MPOOL_DEBUG*/
11 #define DPRINTF(a) printf a
16 /* `flags' bits in blknode data structure */
17 #define MPOOL_NODE_AVAIL (1 << 0) /* If not set, node is reserved, else available */
18 #define MPOOL_NODE_LR (1 << 1) /* If not set, node is left buddy, else right buddy */
19 #define MPOOL_NODE_PARENT (1 << 2) /* If not set, parent is left buddy, else right buddy */
21 #define MPOOL_BLOCK_USED 0 /* Block is used */
22 #define MPOOL_BLOCK_AVAIL 1 /* Block is available */
23 #define MPOOL_BLOCK_LEFT 2 /* Block is left buddy */
24 #define MPOOL_BLOCK_RIGHT 3 /* Block is right buddy */
25 #define MPOOL_BLOCK_PARENT 4 /* Block's parent is right buddy */
27 /* Macro definitions */
28 #define MPOOL_MARK_AVAIL(pnode) pnode->flags |= MPOOL_NODE_AVAIL
29 #define MPOOL_MARK_USED(pnode) pnode->flags &= ~MPOOL_NODE_AVAIL
30 #define MPOOL_MARK_LEFT(pnode) pnode->flags &= ~MPOOL_NODE_LR
31 #define MPOOL_MARK_RIGHT(pnode) pnode->flags |= MPOOL_NODE_LR
33 #define MPOOL_IS_AVAIL(pnode) ((pnode->flags & MPOOL_NODE_AVAIL) != 0)
34 #define MPOOL_IS_USED(pnode) ((pnode->flags & MPOOL_NODE_AVAIL) == 0)
35 #define MPOOL_IS_LEFT(pnode) ((pnode->flags & MPOOL_NODE_LR) == 0)
36 #define MPOOL_IS_RIGHT(pnode) ((pnode->flags & MPOOL_NODE_LR) != 0)
38 /* This macro is provided for easy initialization of a blknode structure */
39 #define MPOOL_BLOCK_INIT(_node, _base, _ptr, _avail, _lr, _parent, _logsize) \
43 _node->logsize = _logsize; \
46 if ((_avail) == MPOOL_BLOCK_AVAIL) \
47 _node->flags |= MPOOL_NODE_AVAIL; \
49 _node->flags &= ~MPOOL_NODE_AVAIL; \
51 /* Left-Right relationship */ \
52 if ((_lr) == MPOOL_BLOCK_RIGHT) \
53 _node->flags |= MPOOL_NODE_LR; \
55 _node->flags &= ~MPOOL_NODE_LR; \
57 /* Parent L-R relationship */ \
58 if ((_parent) == MPOOL_BLOCK_PARENT) \
59 _node->flags |= MPOOL_NODE_PARENT; \
61 _node->flags &= ~MPOOL_NODE_PARENT; \
64 typedef struct blknode
{
65 unsigned char flags
; /* availability, left-right buddiness, inheritance */
66 size_t logsize
; /* logarithm of size with base 2 */
67 void *ptr
; /* pointer to beginning of free block (what mpool_alloc() returns) */
68 LIST_ENTRY(blknode
) next_chunk
;
71 typedef struct mpool
{
73 size_t nblocks
; /* nblocks = logsize + 1 */
74 size_t maxlogsize
; /* logarithm of maximum size of chunk with base 2 */
75 size_t minlogsize
; /* logarithm of minimum size of chunk with base 2 */
77 size_t nsplits
; /* number of splits made */
78 size_t nmerges
; /* number of merges made */
80 LIST_HEAD(blkhead
, blknode
) *blktable
;
83 typedef struct blkhead blkhead_t
;
91 /* Function prototypes */
92 mpret_t
mpool_init(mpool_t
**mpool
, size_t maxlogsize
, size_t minlogsize
);
93 void *mpool_alloc(mpool_t
*mpool
, size_t blksize
);
94 void mpool_free(mpool_t
*mpool
, void *ptr
);
95 void mpool_destroy(mpool_t
*mpool
);