1 /* 2 * regional.c -- region based memory allocator. 3 * 4 * Copyright (c) 2001-2006, NLnet Labs. All rights reserved. 5 * 6 * Copyright (c) 2007, NLnet Labs. All rights reserved. 7 * 8 * This software is open source. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 14 * Redistributions of source code must retain the above copyright notice, 15 * this list of conditions and the following disclaimer. 16 * 17 * Redistributions in binary form must reproduce the above copyright notice, 18 * this list of conditions and the following disclaimer in the documentation 19 * and/or other materials provided with the distribution. 20 * 21 * Neither the name of the NLNET LABS nor the names of its contributors may 22 * be used to endorse or promote products derived from this software without 23 * specific prior written permission. 24 * 25 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 26 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 27 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 28 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 29 * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 30 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED 31 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 32 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF 33 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 34 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 35 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 36 */ 37 38 /** 39 * \file 40 * Regional allocator. Allocates small portions of of larger chunks. 41 */ 42 43 #include "config.h" 44 #include "util/log.h" 45 #include "util/regional.h" 46 47 #ifdef ALIGNMENT 48 # undef ALIGNMENT 49 #endif 50 /** increase size until it fits alignment of s bytes */ 51 #define ALIGN_UP(x, s) (((x) + s - 1) & (~(s - 1))) 52 /** what size to align on; make sure a char* fits in it. */ 53 #define ALIGNMENT (sizeof(uint64_t)) 54 55 /** Default reasonable size for chunks */ 56 #define REGIONAL_CHUNK_SIZE 8192 57 #ifdef UNBOUND_ALLOC_NONREGIONAL 58 /** All objects allocated outside of chunks, for debug */ 59 #define REGIONAL_LARGE_OBJECT_SIZE 0 60 #else 61 /** Default size for large objects - allocated outside of chunks. */ 62 #define REGIONAL_LARGE_OBJECT_SIZE 2048 63 #endif 64 65 struct regional* 66 regional_create(void) 67 { 68 return regional_create_custom(REGIONAL_CHUNK_SIZE); 69 } 70 71 /** init regional struct with first block */ 72 static void 73 regional_init(struct regional* r) 74 { 75 size_t a = ALIGN_UP(sizeof(struct regional), ALIGNMENT); 76 r->data = (char*)r + a; 77 r->available = r->first_size - a; 78 r->next = NULL; 79 r->large_list = NULL; 80 r->total_large = 0; 81 } 82 83 struct regional* 84 regional_create_custom(size_t size) 85 { 86 struct regional* r = (struct regional*)malloc(size); 87 log_assert(sizeof(struct regional) <= size); 88 if(!r) return NULL; 89 r->first_size = size; 90 regional_init(r); 91 return r; 92 } 93 94 void 95 regional_free_all(struct regional *r) 96 { 97 char* p = r->next, *np; 98 while(p) { 99 np = *(char**)p; 100 free(p); 101 p = np; 102 } 103 p = r->large_list; 104 while(p) { 105 np = *(char**)p; 106 free(p); 107 p = np; 108 } 109 regional_init(r); 110 } 111 112 void 113 regional_destroy(struct regional *r) 114 { 115 if(!r) return; 116 regional_free_all(r); 117 free(r); 118 } 119 120 void * 121 regional_alloc(struct regional *r, size_t size) 122 { 123 size_t a = ALIGN_UP(size, ALIGNMENT); 124 void *s; 125 /* large objects */ 126 if(a > REGIONAL_LARGE_OBJECT_SIZE) { 127 s = malloc(ALIGNMENT + size); 128 if(!s) return NULL; 129 r->total_large += ALIGNMENT+size; 130 *(char**)s = r->large_list; 131 r->large_list = (char*)s; 132 return (char*)s+ALIGNMENT; 133 } 134 /* create a new chunk */ 135 if(a > r->available) { 136 s = malloc(REGIONAL_CHUNK_SIZE); 137 if(!s) return NULL; 138 *(char**)s = r->next; 139 r->next = (char*)s; 140 r->data = (char*)s + ALIGNMENT; 141 r->available = REGIONAL_CHUNK_SIZE - ALIGNMENT; 142 } 143 /* put in this chunk */ 144 r->available -= a; 145 s = r->data; 146 r->data += a; 147 return s; 148 } 149 150 void * 151 regional_alloc_init(struct regional* r, const void *init, size_t size) 152 { 153 void *s = regional_alloc(r, size); 154 if(!s) return NULL; 155 memcpy(s, init, size); 156 return s; 157 } 158 159 void * 160 regional_alloc_zero(struct regional *r, size_t size) 161 { 162 void *s = regional_alloc(r, size); 163 if(!s) return NULL; 164 memset(s, 0, size); 165 return s; 166 } 167 168 char * 169 regional_strdup(struct regional *r, const char *string) 170 { 171 return (char*)regional_alloc_init(r, string, strlen(string)+1); 172 } 173 174 /** 175 * reasonably slow, but stats and get_mem are not supposed to be fast 176 * count the number of chunks in use 177 */ 178 static size_t 179 count_chunks(struct regional* r) 180 { 181 size_t c = 1; 182 char* p = r->next; 183 while(p) { 184 c++; 185 p = *(char**)p; 186 } 187 return c; 188 } 189 190 /** 191 * also reasonably slow, counts the number of large objects 192 */ 193 static size_t 194 count_large(struct regional* r) 195 { 196 size_t c = 0; 197 char* p = r->large_list; 198 while(p) { 199 c++; 200 p = *(char**)p; 201 } 202 return c; 203 } 204 205 void 206 regional_log_stats(struct regional *r) 207 { 208 /* some basic assertions put here (non time critical code) */ 209 log_assert(ALIGNMENT >= sizeof(char*)); 210 log_assert(REGIONAL_CHUNK_SIZE > ALIGNMENT); 211 log_assert(REGIONAL_CHUNK_SIZE-ALIGNMENT > REGIONAL_LARGE_OBJECT_SIZE); 212 log_assert(REGIONAL_CHUNK_SIZE >= sizeof(struct regional)); 213 /* debug print */ 214 log_info("regional %u chunks, %u large", 215 (unsigned)count_chunks(r), (unsigned)count_large(r)); 216 } 217 218 size_t 219 regional_get_mem(struct regional* r) 220 { 221 return r->first_size + (count_chunks(r)-1)*REGIONAL_CHUNK_SIZE 222 + r->total_large; 223 } 224