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 */
12bool
13rtree_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
30static rtree_node_elm_t *
31rtree_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}
35rtree_node_alloc_t *JET_MUTABLE rtree_node_alloc = rtree_node_alloc_impl;
36
37static void
38rtree_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}
42rtree_node_dalloc_t *JET_MUTABLE rtree_node_dalloc =
43 rtree_node_dalloc_impl;
44
45static rtree_leaf_elm_t *
46rtree_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}
50rtree_leaf_alloc_t *JET_MUTABLE rtree_leaf_alloc = rtree_leaf_alloc_impl;
51
52static void
53rtree_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}
57rtree_leaf_dalloc_t *JET_MUTABLE rtree_leaf_dalloc =
58 rtree_leaf_dalloc_impl;
59
60#ifdef JEMALLOC_JET
61# if RTREE_HEIGHT > 1
62static void
63rtree_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
93void
94rtree_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
101static rtree_node_elm_t *
102rtree_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
128static rtree_leaf_elm_t *
129rtree_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
154static bool
155rtree_node_valid(rtree_node_elm_t *node) {
156 return ((uintptr_t)node != (uintptr_t)0);
157}
158
159static bool
160rtree_leaf_valid(rtree_leaf_elm_t *leaf) {
161 return ((uintptr_t)leaf != (uintptr_t)0);
162}
163
164static rtree_node_elm_t *
165rtree_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
180static rtree_node_elm_t *
181rtree_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
193static rtree_leaf_elm_t *
194rtree_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
209static rtree_leaf_elm_t *
210rtree_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
222rtree_leaf_elm_t *
223rtree_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
308void
309rtree_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