1 #define JEMALLOC_RTREE_C_ 2 #include "jemalloc/internal/jemalloc_preamble.h" 3 #include "jemalloc/internal/jemalloc_internal_includes.h" 4 5 #include "jemalloc/internal/assert.h" 6 #include "jemalloc/internal/mutex.h" 7 8 /* 9 * Only the most significant bits of keys passed to rtree_{read,write}() are 10 * used. 11 */ 12 bool 13 rtree_new(rtree_t *rtree, bool zeroed) { 14 #ifdef JEMALLOC_JET 15 if (!zeroed) { 16 memset(rtree, 0, sizeof(rtree_t)); /* Clear root. */ 17 } 18 #else 19 assert(zeroed); 20 #endif 21 22 if (malloc_mutex_init(&rtree->init_lock, "rtree", WITNESS_RANK_RTREE, 23 malloc_mutex_rank_exclusive)) { 24 return true; 25 } 26 27 return false; 28 } 29 30 static rtree_node_elm_t * 31 rtree_node_alloc_impl(tsdn_t *tsdn, rtree_t *rtree, size_t nelms) { 32 return (rtree_node_elm_t *)base_alloc(tsdn, b0get(), nelms * 33 sizeof(rtree_node_elm_t), CACHELINE); 34 } 35 rtree_node_alloc_t *JET_MUTABLE rtree_node_alloc = rtree_node_alloc_impl; 36 37 static void 38 rtree_node_dalloc_impl(tsdn_t *tsdn, rtree_t *rtree, rtree_node_elm_t *node) { 39 /* Nodes are never deleted during normal operation. */ 40 not_reached(); 41 } 42 rtree_node_dalloc_t *JET_MUTABLE rtree_node_dalloc = 43 rtree_node_dalloc_impl; 44 45 static rtree_leaf_elm_t * 46 rtree_leaf_alloc_impl(tsdn_t *tsdn, rtree_t *rtree, size_t nelms) { 47 return (rtree_leaf_elm_t *)base_alloc(tsdn, b0get(), nelms * 48 sizeof(rtree_leaf_elm_t), CACHELINE); 49 } 50 rtree_leaf_alloc_t *JET_MUTABLE rtree_leaf_alloc = rtree_leaf_alloc_impl; 51 52 static void 53 rtree_leaf_dalloc_impl(tsdn_t *tsdn, rtree_t *rtree, rtree_leaf_elm_t *leaf) { 54 /* Leaves are never deleted during normal operation. */ 55 not_reached(); 56 } 57 rtree_leaf_dalloc_t *JET_MUTABLE rtree_leaf_dalloc = 58 rtree_leaf_dalloc_impl; 59 60 #ifdef JEMALLOC_JET 61 # if RTREE_HEIGHT > 1 62 static void 63 rtree_delete_subtree(tsdn_t *tsdn, rtree_t *rtree, rtree_node_elm_t *subtree, 64 unsigned level) { 65 size_t nchildren = ZU(1) << rtree_levels[level].bits; 66 if (level + 2 < RTREE_HEIGHT) { 67 for (size_t i = 0; i < nchildren; i++) { 68 rtree_node_elm_t *node = 69 (rtree_node_elm_t *)atomic_load_p(&subtree[i].child, 70 ATOMIC_RELAXED); 71 if (node != NULL) { 72 rtree_delete_subtree(tsdn, rtree, node, level + 73 1); 74 } 75 } 76 } else { 77 for (size_t i = 0; i < nchildren; i++) { 78 rtree_leaf_elm_t *leaf = 79 (rtree_leaf_elm_t *)atomic_load_p(&subtree[i].child, 80 ATOMIC_RELAXED); 81 if (leaf != NULL) { 82 rtree_leaf_dalloc(tsdn, rtree, leaf); 83 } 84 } 85 } 86 87 if (subtree != rtree->root) { 88 rtree_node_dalloc(tsdn, rtree, subtree); 89 } 90 } 91 # endif 92 93 void 94 rtree_delete(tsdn_t *tsdn, rtree_t *rtree) { 95 # if RTREE_HEIGHT > 1 96 rtree_delete_subtree(tsdn, rtree, rtree->root, 0); 97 # endif 98 } 99 #endif 100 101 static rtree_node_elm_t * 102 rtree_node_init(tsdn_t *tsdn, rtree_t *rtree, unsigned level, 103 atomic_p_t *elmp) { 104 malloc_mutex_lock(tsdn, &rtree->init_lock); 105 /* 106 * If *elmp is non-null, then it was initialized with the init lock 107 * held, so we can get by with 'relaxed' here. 108 */ 109 rtree_node_elm_t *node = atomic_load_p(elmp, ATOMIC_RELAXED); 110 if (node == NULL) { 111 node = rtree_node_alloc(tsdn, rtree, ZU(1) << 112 rtree_levels[level].bits); 113 if (node == NULL) { 114 malloc_mutex_unlock(tsdn, &rtree->init_lock); 115 return NULL; 116 } 117 /* 118 * Even though we hold the lock, a later reader might not; we 119 * need release semantics. 120 */ 121 atomic_store_p(elmp, node, ATOMIC_RELEASE); 122 } 123 malloc_mutex_unlock(tsdn, &rtree->init_lock); 124 125 return node; 126 } 127 128 static rtree_leaf_elm_t * 129 rtree_leaf_init(tsdn_t *tsdn, rtree_t *rtree, atomic_p_t *elmp) { 130 malloc_mutex_lock(tsdn, &rtree->init_lock); 131 /* 132 * If *elmp is non-null, then it was initialized with the init lock 133 * held, so we can get by with 'relaxed' here. 134 */ 135 rtree_leaf_elm_t *leaf = atomic_load_p(elmp, ATOMIC_RELAXED); 136 if (leaf == NULL) { 137 leaf = rtree_leaf_alloc(tsdn, rtree, ZU(1) << 138 rtree_levels[RTREE_HEIGHT-1].bits); 139 if (leaf == NULL) { 140 malloc_mutex_unlock(tsdn, &rtree->init_lock); 141 return NULL; 142 } 143 /* 144 * Even though we hold the lock, a later reader might not; we 145 * need release semantics. 146 */ 147 atomic_store_p(elmp, leaf, ATOMIC_RELEASE); 148 } 149 malloc_mutex_unlock(tsdn, &rtree->init_lock); 150 151 return leaf; 152 } 153 154 static bool 155 rtree_node_valid(rtree_node_elm_t *node) { 156 return ((uintptr_t)node != (uintptr_t)0); 157 } 158 159 static bool 160 rtree_leaf_valid(rtree_leaf_elm_t *leaf) { 161 return ((uintptr_t)leaf != (uintptr_t)0); 162 } 163 164 static rtree_node_elm_t * 165 rtree_child_node_tryread(rtree_node_elm_t *elm, bool dependent) { 166 rtree_node_elm_t *node; 167 168 if (dependent) { 169 node = (rtree_node_elm_t *)atomic_load_p(&elm->child, 170 ATOMIC_RELAXED); 171 } else { 172 node = (rtree_node_elm_t *)atomic_load_p(&elm->child, 173 ATOMIC_ACQUIRE); 174 } 175 176 assert(!dependent || node != NULL); 177 return node; 178 } 179 180 static rtree_node_elm_t * 181 rtree_child_node_read(tsdn_t *tsdn, rtree_t *rtree, rtree_node_elm_t *elm, 182 unsigned level, bool dependent) { 183 rtree_node_elm_t *node; 184 185 node = rtree_child_node_tryread(elm, dependent); 186 if (!dependent && unlikely(!rtree_node_valid(node))) { 187 node = rtree_node_init(tsdn, rtree, level + 1, &elm->child); 188 } 189 assert(!dependent || node != NULL); 190 return node; 191 } 192 193 static rtree_leaf_elm_t * 194 rtree_child_leaf_tryread(rtree_node_elm_t *elm, bool dependent) { 195 rtree_leaf_elm_t *leaf; 196 197 if (dependent) { 198 leaf = (rtree_leaf_elm_t *)atomic_load_p(&elm->child, 199 ATOMIC_RELAXED); 200 } else { 201 leaf = (rtree_leaf_elm_t *)atomic_load_p(&elm->child, 202 ATOMIC_ACQUIRE); 203 } 204 205 assert(!dependent || leaf != NULL); 206 return leaf; 207 } 208 209 static rtree_leaf_elm_t * 210 rtree_child_leaf_read(tsdn_t *tsdn, rtree_t *rtree, rtree_node_elm_t *elm, 211 unsigned level, bool dependent) { 212 rtree_leaf_elm_t *leaf; 213 214 leaf = rtree_child_leaf_tryread(elm, dependent); 215 if (!dependent && unlikely(!rtree_leaf_valid(leaf))) { 216 leaf = rtree_leaf_init(tsdn, rtree, &elm->child); 217 } 218 assert(!dependent || leaf != NULL); 219 return leaf; 220 } 221 222 rtree_leaf_elm_t * 223 rtree_leaf_elm_lookup_hard(tsdn_t *tsdn, rtree_t *rtree, rtree_ctx_t *rtree_ctx, 224 uintptr_t key, bool dependent, bool init_missing) { 225 rtree_node_elm_t *node; 226 rtree_leaf_elm_t *leaf; 227 #if RTREE_HEIGHT > 1 228 node = rtree->root; 229 #else 230 leaf = rtree->root; 231 #endif 232 233 if (config_debug) { 234 uintptr_t leafkey = rtree_leafkey(key); 235 for (unsigned i = 0; i < RTREE_CTX_NCACHE; i++) { 236 assert(rtree_ctx->cache[i].leafkey != leafkey); 237 } 238 for (unsigned i = 0; i < RTREE_CTX_NCACHE_L2; i++) { 239 assert(rtree_ctx->l2_cache[i].leafkey != leafkey); 240 } 241 } 242 243 #define RTREE_GET_CHILD(level) { \ 244 assert(level < RTREE_HEIGHT-1); \ 245 if (level != 0 && !dependent && \ 246 unlikely(!rtree_node_valid(node))) { \ 247 return NULL; \ 248 } \ 249 uintptr_t subkey = rtree_subkey(key, level); \ 250 if (level + 2 < RTREE_HEIGHT) { \ 251 node = init_missing ? \ 252 rtree_child_node_read(tsdn, rtree, \ 253 &node[subkey], level, dependent) : \ 254 rtree_child_node_tryread(&node[subkey], \ 255 dependent); \ 256 } else { \ 257 leaf = init_missing ? \ 258 rtree_child_leaf_read(tsdn, rtree, \ 259 &node[subkey], level, dependent) : \ 260 rtree_child_leaf_tryread(&node[subkey], \ 261 dependent); \ 262 } \ 263 } 264 /* 265 * Cache replacement upon hard lookup (i.e. L1 & L2 rtree cache miss): 266 * (1) evict last entry in L2 cache; (2) move the collision slot from L1 267 * cache down to L2; and 3) fill L1. 268 */ 269 #define RTREE_GET_LEAF(level) { \ 270 assert(level == RTREE_HEIGHT-1); \ 271 if (!dependent && unlikely(!rtree_leaf_valid(leaf))) { \ 272 return NULL; \ 273 } \ 274 if (RTREE_CTX_NCACHE_L2 > 1) { \ 275 memmove(&rtree_ctx->l2_cache[1], \ 276 &rtree_ctx->l2_cache[0], \ 277 sizeof(rtree_ctx_cache_elm_t) * \ 278 (RTREE_CTX_NCACHE_L2 - 1)); \ 279 } \ 280 size_t slot = rtree_cache_direct_map(key); \ 281 rtree_ctx->l2_cache[0].leafkey = \ 282 rtree_ctx->cache[slot].leafkey; \ 283 rtree_ctx->l2_cache[0].leaf = \ 284 rtree_ctx->cache[slot].leaf; \ 285 uintptr_t leafkey = rtree_leafkey(key); \ 286 rtree_ctx->cache[slot].leafkey = leafkey; \ 287 rtree_ctx->cache[slot].leaf = leaf; \ 288 uintptr_t subkey = rtree_subkey(key, level); \ 289 return &leaf[subkey]; \ 290 } 291 if (RTREE_HEIGHT > 1) { 292 RTREE_GET_CHILD(0) 293 } 294 if (RTREE_HEIGHT > 2) { 295 RTREE_GET_CHILD(1) 296 } 297 if (RTREE_HEIGHT > 3) { 298 for (unsigned i = 2; i < RTREE_HEIGHT-1; i++) { 299 RTREE_GET_CHILD(i) 300 } 301 } 302 RTREE_GET_LEAF(RTREE_HEIGHT-1) 303 #undef RTREE_GET_CHILD 304 #undef RTREE_GET_LEAF 305 not_reached(); 306 } 307 308 void 309 rtree_ctx_data_init(rtree_ctx_t *ctx) { 310 for (unsigned i = 0; i < RTREE_CTX_NCACHE; i++) { 311 rtree_ctx_cache_elm_t *cache = &ctx->cache[i]; 312 cache->leafkey = RTREE_LEAFKEY_INVALID; 313 cache->leaf = NULL; 314 } 315 for (unsigned i = 0; i < RTREE_CTX_NCACHE_L2; i++) { 316 rtree_ctx_cache_elm_t *cache = &ctx->l2_cache[i]; 317 cache->leafkey = RTREE_LEAFKEY_INVALID; 318 cache->leaf = NULL; 319 } 320 } 321