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 65struct regional* 66regional_create(void) 67{ 68 return regional_create_custom(REGIONAL_CHUNK_SIZE); 69} 70 71/** init regional struct with first block */ 72static void 73regional_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/** 84 * Create a new region, with custom first block and large-object sizes. 85 * @param size: length of first block. 86 * @param large_object_size: outside of chunk allocation threshold. 87 * @return: newly allocated regional. 88 */ 89static struct regional* 90regional_create_custom_large_object(size_t size, size_t large_object_size) 91{ 92 struct regional* r; 93 size = ALIGN_UP(size, ALIGNMENT); 94 r = (struct regional*)malloc(size); 95 log_assert(sizeof(struct regional) <= size); 96 if(!r) return NULL; 97 r->first_size = size; 98 r->large_object_size = large_object_size; 99 regional_init(r); 100 return r; 101} 102 103struct regional* 104regional_create_custom(size_t size) 105{ 106 return regional_create_custom_large_object(size, 107 REGIONAL_LARGE_OBJECT_SIZE); 108} 109 110struct regional* 111regional_create_nochunk(size_t size) 112{ 113 return regional_create_custom_large_object(size, 0); 114} 115 116void 117regional_free_all(struct regional *r) 118{ 119 char* p = r->next, *np; 120 while(p) { 121 np = *(char**)p; 122 free(p); 123 p = np; 124 } 125 p = r->large_list; 126 while(p) { 127 np = *(char**)p; 128 free(p); 129 p = np; 130 } 131 regional_init(r); 132} 133 134void 135regional_destroy(struct regional *r) 136{ 137 if(!r) return; 138 regional_free_all(r); 139 free(r); 140} 141 142void * 143regional_alloc(struct regional *r, size_t size) 144{ 145 size_t a; 146 void *s; 147 if( 148#if SIZEOF_SIZE_T == 8 149 (unsigned long long)size >= 0xffffffffffffff00ULL 150#else 151 (unsigned)size >= (unsigned)0xffffff00UL 152#endif 153 ) 154 return NULL; /* protect against integer overflow in 155 malloc and ALIGN_UP */ 156 a = ALIGN_UP(size, ALIGNMENT); 157 /* large objects */ 158 if(a > r->large_object_size) { 159 s = malloc(ALIGNMENT + size); 160 if(!s) return NULL; 161 r->total_large += ALIGNMENT+size; 162 *(char**)s = r->large_list; 163 r->large_list = (char*)s; 164 return (char*)s+ALIGNMENT; 165 } 166 /* create a new chunk */ 167 if(a > r->available) { 168 s = malloc(REGIONAL_CHUNK_SIZE); 169 if(!s) return NULL; 170 *(char**)s = r->next; 171 r->next = (char*)s; 172 r->data = (char*)s + ALIGNMENT; 173 r->available = REGIONAL_CHUNK_SIZE - ALIGNMENT; 174 } 175 /* put in this chunk */ 176 r->available -= a; 177 s = r->data; 178 r->data += a; 179 return s; 180} 181 182void * 183regional_alloc_init(struct regional* r, const void *init, size_t size) 184{ 185 void *s = regional_alloc(r, size); 186 if(!s) return NULL; 187 memcpy(s, init, size); 188 return s; 189} 190 191void * 192regional_alloc_zero(struct regional *r, size_t size) 193{ 194 void *s = regional_alloc(r, size); 195 if(!s) return NULL; 196 memset(s, 0, size); 197 return s; 198} 199 200char * 201regional_strdup(struct regional *r, const char *string) 202{ 203 return (char*)regional_alloc_init(r, string, strlen(string)+1); 204} 205 206/** 207 * reasonably slow, but stats and get_mem are not supposed to be fast 208 * count the number of chunks in use 209 */ 210static size_t 211count_chunks(struct regional* r) 212{ 213 size_t c = 1; 214 char* p = r->next; 215 while(p) { 216 c++; 217 p = *(char**)p; 218 } 219 return c; 220} 221 222/** 223 * also reasonably slow, counts the number of large objects 224 */ 225static size_t 226count_large(struct regional* r) 227{ 228 size_t c = 0; 229 char* p = r->large_list; 230 while(p) { 231 c++; 232 p = *(char**)p; 233 } 234 return c; 235} 236 237void 238regional_log_stats(struct regional *r) 239{ 240 /* some basic assertions put here (non time critical code) */ 241 log_assert(ALIGNMENT >= sizeof(char*)); 242 log_assert(REGIONAL_CHUNK_SIZE > ALIGNMENT); 243 log_assert(REGIONAL_CHUNK_SIZE-ALIGNMENT > r->large_object_size); 244 log_assert(REGIONAL_CHUNK_SIZE >= sizeof(struct regional)); 245 /* debug print */ 246 log_info("regional %u chunks, %u large", 247 (unsigned)count_chunks(r), (unsigned)count_large(r)); 248} 249 250size_t 251regional_get_mem(struct regional* r) 252{ 253 return r->first_size + (count_chunks(r)-1)*REGIONAL_CHUNK_SIZE 254 + r->total_large; 255} 256