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| 1 | +/* |
| 2 | + * this is generic pool allocator |
| 3 | + * you should define following macroses: |
| 4 | + * ITEM_NAME - unique identifier, which allows to hold functions in a namespace |
| 5 | + * ITEM_TYPEDEF(name) - passed to typedef to localize item type |
| 6 | + * free_entry - desired name of function for free entry |
| 7 | + * alloc_entry - defired name of function for allocate entry |
| 8 | + */ |
| 9 | + |
| 10 | +#if POOL_ALLOC_PART == 1 |
| 11 | +#ifdef HEAP_ALIGN_LOG |
| 12 | +#define DEFAULT_POOL_SIZE (1 << HEAP_ALIGN_LOG) |
| 13 | +#else |
| 14 | +#define DEFAULT_POOL_SIZE (sizeof(void*) * 2048) |
| 15 | +#endif |
| 16 | +typedef unsigned int pool_holder_counter; |
| 17 | + |
| 18 | +typedef struct pool_entry_list pool_entry_list; |
| 19 | +typedef struct pool_holder pool_holder; |
| 20 | + |
| 21 | +typedef struct pool_header { |
| 22 | + pool_holder *first; |
| 23 | + pool_holder *_black_magick; |
| 24 | + pool_holder_counter size; /* size of entry in sizeof(void*) items */ |
| 25 | + pool_holder_counter total; |
| 26 | +} pool_header; |
| 27 | + |
| 28 | +struct pool_holder { |
| 29 | + pool_holder_counter free, total; |
| 30 | + pool_header *header; |
| 31 | + void *freep; |
| 32 | + pool_holder *fore, *back; |
| 33 | + void *data[1]; |
| 34 | +}; |
| 35 | +#define POOL_DATA_SIZE(pool_size) (((pool_size) - sizeof(void*) * 6 - offsetof(pool_holder, data)) / sizeof(void*)) |
| 36 | +#define POOL_ENTRY_SIZE(item_type) ((sizeof(item_type) - 1) / sizeof(void*) + 1) |
| 37 | +#define POOL_HOLDER_COUNT(pool_size, item_type) (POOL_DATA_SIZE(pool_size)/POOL_ENTRY_SIZE(item_type)) |
| 38 | +#define INIT_POOL(item_type) {NULL, NULL, POOL_ENTRY_SIZE(item_type), POOL_HOLDER_COUNT(DEFAULT_POOL_SIZE, item_type)} |
| 39 | + |
| 40 | +#elif POOL_ALLOC_PART == 2 |
| 41 | +static pool_holder * |
| 42 | +pool_holder_alloc(pool_header *header) |
| 43 | +{ |
| 44 | + pool_holder *holder; |
| 45 | + pool_holder_counter i, size, count; |
| 46 | + register void **ptr; |
| 47 | + |
| 48 | + size_t sz = offsetof(pool_holder, data) + |
| 49 | + header->size * header->total * sizeof(void*); |
| 50 | +#define objspace (&rb_objspace) |
| 51 | + objspace_malloc_prepare(objspace, DEFAULT_POOL_SIZE); |
| 52 | + if (header->first != NULL) return header->first; |
| 53 | + TRY_WITH_GC(holder = (pool_holder*) aligned_malloc(DEFAULT_POOL_SIZE, sz)); |
| 54 | + malloc_increase += DEFAULT_POOL_SIZE; |
| 55 | +#if CALC_EXACT_MALLOC_SIZE |
| 56 | + objspace->malloc_params.allocated_size += DEFAULT_POOL_SIZE; |
| 57 | + objspace->malloc_params.allocations++; |
| 58 | +#endif |
| 59 | +#undef objspace |
| 60 | + |
| 61 | + size = header->size; |
| 62 | + count = header->total; |
| 63 | + holder->free = count; |
| 64 | + holder->total = count; |
| 65 | + holder->header = header; |
| 66 | + holder->fore = NULL; |
| 67 | + holder->back = NULL; |
| 68 | + holder->freep = &holder->data; |
| 69 | + ptr = holder->data; |
| 70 | + for(i = count - 1; i; i-- ) { |
| 71 | + ptr = *ptr = ptr + size; |
| 72 | + } |
| 73 | + *ptr = NULL; |
| 74 | + header->first = holder; |
| 75 | + return holder; |
| 76 | +} |
| 77 | + |
| 78 | +static inline void |
| 79 | +pool_holder_unchaing(pool_header *header, pool_holder *holder) |
| 80 | +{ |
| 81 | + register pool_holder *fore = holder->fore, *back = holder->back; |
| 82 | + holder->fore = NULL; |
| 83 | + holder->back = NULL; |
| 84 | + if (fore != NULL) fore->back = back; |
| 85 | + else header->_black_magick = back; |
| 86 | + if (back != NULL) back->fore = fore; |
| 87 | + else header->first = fore; |
| 88 | +} |
| 89 | + |
| 90 | +static inline pool_holder * |
| 91 | +entry_holder(void **entry) |
| 92 | +{ |
| 93 | + return (pool_holder*)(((uintptr_t)entry) & ~(DEFAULT_POOL_SIZE - 1)); |
| 94 | +} |
| 95 | + |
| 96 | +static inline void |
| 97 | +pool_free_entry(void **entry) |
| 98 | +{ |
| 99 | + pool_holder *holder = entry_holder(entry); |
| 100 | + pool_header *header = holder->header; |
| 101 | + |
| 102 | + if (holder->free++ == 0) { |
| 103 | + register pool_holder *first = header->first; |
| 104 | + if (first == NULL) { |
| 105 | + header->first = holder; |
| 106 | + } else { |
| 107 | + holder->back = first; |
| 108 | + holder->fore = first->fore; |
| 109 | + first->fore = holder; |
| 110 | + if (holder->fore) |
| 111 | + holder->fore->back = holder; |
| 112 | + else |
| 113 | + header->_black_magick = holder; |
| 114 | + } |
| 115 | + } else if (holder->free == holder->total && header->first != holder ) { |
| 116 | + pool_holder_unchaing(header, holder); |
| 117 | + aligned_free(holder); |
| 118 | +#if CALC_EXACT_MALLOC_SIZE |
| 119 | + rb_objspace.malloc_params.allocated_size -= DEFAULT_POOL_SIZE; |
| 120 | + rb_objspace.malloc_params.allocations--; |
| 121 | +#endif |
| 122 | + return; |
| 123 | + } |
| 124 | + |
| 125 | + *entry = holder->freep; |
| 126 | + holder->freep = entry; |
| 127 | +} |
| 128 | + |
| 129 | +static inline void* |
| 130 | +pool_alloc_entry(pool_header *header) |
| 131 | +{ |
| 132 | + pool_holder *holder = header->first; |
| 133 | + void **result; |
| 134 | + if (holder == NULL) { |
| 135 | + holder = pool_holder_alloc(header); |
| 136 | + } |
| 137 | + |
| 138 | + result = holder->freep; |
| 139 | + holder->freep = *result; |
| 140 | + |
| 141 | + if (--holder->free == 0) { |
| 142 | + pool_holder_unchaing(header, holder); |
| 143 | + } |
| 144 | + |
| 145 | + return result; |
| 146 | +} |
| 147 | + |
| 148 | +static void |
| 149 | +pool_finalize_header(pool_header *header) |
| 150 | +{ |
| 151 | + if (header->first) { |
| 152 | + aligned_free(header->first); |
| 153 | + header->first = NULL; |
| 154 | + } |
| 155 | +} |
| 156 | +#endif |
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