1 /* 2 * Copyright 2010, Ingo Weinhold <ingo_weinhold@gmx.de>. 3 * Copyright 2007, Hugo Santos. All Rights Reserved. 4 * Distributed under the terms of the MIT License. 5 */ 6 7 8 #include "slab_private.h" 9 10 #include <stdio.h> 11 #include <string.h> 12 13 #include <algorithm> 14 15 #include <debug.h> 16 #include <heap.h> 17 #include <kernel.h> // for ROUNDUP 18 #include <malloc.h> 19 #include <vm/vm.h> 20 #include <vm/VMAddressSpace.h> 21 22 #include "ObjectCache.h" 23 #include "MemoryManager.h" 24 25 26 //#define TEST_ALL_CACHES_DURING_BOOT 27 28 static const size_t kBlockSizes[] = { 29 16, 24, 32, 48, 64, 80, 96, 112, 30 128, 160, 192, 224, 256, 320, 384, 448, 31 512, 640, 768, 896, 1024, 1280, 1536, 1792, 32 2048, 2560, 3072, 3584, 4096, 4608, 5120, 5632, 33 6144, 6656, 7168, 7680, 8192, 34 0 35 }; 36 37 static const size_t kNumBlockSizes = sizeof(kBlockSizes) / sizeof(size_t) - 1; 38 39 static object_cache* sBlockCaches[kNumBlockSizes]; 40 41 static addr_t sBootStrapMemory = 0; 42 static size_t sBootStrapMemorySize = 0; 43 static size_t sUsedBootStrapMemory = 0; 44 45 46 RANGE_MARKER_FUNCTION_BEGIN(slab_allocator) 47 48 49 static int 50 size_to_index(size_t size) 51 { 52 if (size <= 16) 53 return 0; 54 if (size <= 32) 55 return 1 + (size - 16 - 1) / 8; 56 if (size <= 128) 57 return 3 + (size - 32 - 1) / 16; 58 if (size <= 256) 59 return 9 + (size - 128 - 1) / 32; 60 if (size <= 512) 61 return 13 + (size - 256 - 1) / 64; 62 if (size <= 1024) 63 return 17 + (size - 512 - 1) / 128; 64 if (size <= 2048) 65 return 21 + (size - 1024 - 1) / 256; 66 if (size <= 8192) 67 return 25 + (size - 2048 - 1) / 512; 68 69 return -1; 70 } 71 72 73 static void* 74 block_alloc(size_t size, size_t alignment, uint32 flags) 75 { 76 if (alignment > kMinObjectAlignment) { 77 // Make size >= alignment and a power of two. This is sufficient, since 78 // all of our object caches with power of two sizes are aligned. We may 79 // waste quite a bit of memory, but memalign() is very rarely used 80 // in the kernel and always with power of two size == alignment anyway. 81 ASSERT((alignment & (alignment - 1)) == 0); 82 while (alignment < size) 83 alignment <<= 1; 84 size = alignment; 85 86 // If we're not using an object cache, make sure that the memory 87 // manager knows it has to align the allocation. 88 if (size > kBlockSizes[kNumBlockSizes]) 89 flags |= CACHE_ALIGN_ON_SIZE; 90 } 91 92 // allocate from the respective object cache, if any 93 int index = size_to_index(size); 94 if (index >= 0) 95 return object_cache_alloc(sBlockCaches[index], flags); 96 97 // the allocation is too large for our object caches -- ask the memory 98 // manager 99 void* block; 100 if (MemoryManager::AllocateRaw(size, flags, block) != B_OK) 101 return NULL; 102 103 return block; 104 } 105 106 107 void* 108 block_alloc_early(size_t size) 109 { 110 int index = size_to_index(size); 111 if (index >= 0 && sBlockCaches[index] != NULL) 112 return object_cache_alloc(sBlockCaches[index], CACHE_DURING_BOOT); 113 114 if (size > SLAB_CHUNK_SIZE_SMALL) { 115 // This is a sufficiently large allocation -- just ask the memory 116 // manager directly. 117 void* block; 118 if (MemoryManager::AllocateRaw(size, 0, block) != B_OK) 119 return NULL; 120 121 return block; 122 } 123 124 // A small allocation, but no object cache yet. Use the bootstrap memory. 125 // This allocation must never be freed! 126 if (sBootStrapMemorySize - sUsedBootStrapMemory < size) { 127 // We need more memory. 128 void* block; 129 if (MemoryManager::AllocateRaw(SLAB_CHUNK_SIZE_SMALL, 0, block) != B_OK) 130 return NULL; 131 sBootStrapMemory = (addr_t)block; 132 sBootStrapMemorySize = SLAB_CHUNK_SIZE_SMALL; 133 sUsedBootStrapMemory = 0; 134 } 135 136 size_t neededSize = ROUNDUP(size, sizeof(double)); 137 if (sUsedBootStrapMemory + neededSize > sBootStrapMemorySize) 138 return NULL; 139 void* block = (void*)(sBootStrapMemory + sUsedBootStrapMemory); 140 sUsedBootStrapMemory += neededSize; 141 142 return block; 143 } 144 145 146 static void 147 block_free(void* block, uint32 flags) 148 { 149 if (block == NULL) 150 return; 151 152 ObjectCache* cache = MemoryManager::FreeRawOrReturnCache(block, flags); 153 if (cache != NULL) { 154 // a regular small allocation 155 ASSERT(cache->object_size >= kBlockSizes[0]); 156 ASSERT(cache->object_size <= kBlockSizes[kNumBlockSizes - 1]); 157 ASSERT(cache == sBlockCaches[size_to_index(cache->object_size)]); 158 object_cache_free(cache, block, flags); 159 } 160 } 161 162 163 void 164 block_allocator_init_boot() 165 { 166 for (int index = 0; kBlockSizes[index] != 0; index++) { 167 char name[32]; 168 snprintf(name, sizeof(name), "block allocator: %lu", 169 kBlockSizes[index]); 170 171 uint32 flags = CACHE_DURING_BOOT; 172 size_t size = kBlockSizes[index]; 173 174 // align the power of two objects to their size 175 size_t alignment = (size & (size - 1)) == 0 ? size : 0; 176 177 // For the larger allocation sizes disable the object depot, so we don't 178 // keep lot's of unused objects around. 179 if (size > 2048) 180 flags |= CACHE_NO_DEPOT; 181 182 sBlockCaches[index] = create_object_cache_etc(name, size, alignment, 0, 183 0, 0, flags, NULL, NULL, NULL, NULL); 184 if (sBlockCaches[index] == NULL) 185 panic("allocator: failed to init block cache"); 186 } 187 } 188 189 190 void 191 block_allocator_init_rest() 192 { 193 #ifdef TEST_ALL_CACHES_DURING_BOOT 194 for (int index = 0; kBlockSizes[index] != 0; index++) { 195 block_free(block_alloc(kBlockSizes[index] - sizeof(boundary_tag)), 0, 196 0); 197 } 198 #endif 199 } 200 201 202 // #pragma mark - public API 203 204 205 #if USE_SLAB_ALLOCATOR_FOR_MALLOC 206 207 208 void* 209 memalign(size_t alignment, size_t size) 210 { 211 return block_alloc(size, alignment, 0); 212 } 213 214 215 void * 216 memalign_etc(size_t alignment, size_t size, uint32 flags) 217 { 218 return block_alloc(size, alignment, flags & CACHE_ALLOC_FLAGS); 219 } 220 221 222 int 223 posix_memalign(void** _pointer, size_t alignment, size_t size) 224 { 225 if ((alignment & (sizeof(void*) - 1)) != 0 || _pointer == NULL) 226 return B_BAD_VALUE; 227 *_pointer = block_alloc(size, alignment, 0); 228 return 0; 229 } 230 231 232 void * 233 aligned_alloc(size_t alignment, size_t size) 234 { 235 if ((size % alignment) != 0) 236 return NULL; 237 238 return memalign(alignment, size); 239 } 240 241 242 void 243 free_etc(void *address, uint32 flags) 244 { 245 if ((flags & CACHE_DONT_LOCK_KERNEL_SPACE) != 0) { 246 deferred_free(address); 247 return; 248 } 249 250 block_free(address, flags & CACHE_ALLOC_FLAGS); 251 } 252 253 254 void* 255 malloc(size_t size) 256 { 257 return block_alloc(size, 0, 0); 258 } 259 260 261 void 262 free(void* address) 263 { 264 block_free(address, 0); 265 } 266 267 268 void* 269 realloc(void* address, size_t newSize) 270 { 271 if (newSize == 0) { 272 block_free(address, 0); 273 return NULL; 274 } 275 276 if (address == NULL) 277 return block_alloc(newSize, 0, 0); 278 279 size_t oldSize; 280 ObjectCache* cache = MemoryManager::GetAllocationInfo(address, oldSize); 281 if (cache == NULL && oldSize == 0) { 282 panic("block_realloc(): allocation %p not known", address); 283 return NULL; 284 } 285 286 if (oldSize == newSize) 287 return address; 288 289 void* newBlock = block_alloc(newSize, 0, 0); 290 if (newBlock == NULL) 291 return NULL; 292 293 memcpy(newBlock, address, std::min(oldSize, newSize)); 294 295 block_free(address, 0); 296 297 return newBlock; 298 } 299 300 301 #endif // USE_SLAB_ALLOCATOR_FOR_MALLOC 302 303 304 RANGE_MARKER_FUNCTION_END(slab_allocator) 305