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a42cc659 MD |
1 | #ifndef _URCU_RCULFHASH_H |
2 | #define _URCU_RCULFHASH_H | |
ab7d5fc6 | 3 | |
f0c29ed7 MD |
4 | /* |
5 | * urcu/rculfhash.h | |
6 | * | |
7 | * Userspace RCU library - Lock-Free RCU Hash Table | |
8 | * | |
9 | * Copyright 2011 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com> | |
0dcf4847 | 10 | * Copyright 2011 - Lai Jiangshan <laijs@cn.fujitsu.com> |
f0c29ed7 MD |
11 | * |
12 | * This library is free software; you can redistribute it and/or | |
13 | * modify it under the terms of the GNU Lesser General Public | |
14 | * License as published by the Free Software Foundation; either | |
15 | * version 2.1 of the License, or (at your option) any later version. | |
16 | * | |
17 | * This library is distributed in the hope that it will be useful, | |
18 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
19 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
20 | * Lesser General Public License for more details. | |
21 | * | |
22 | * You should have received a copy of the GNU Lesser General Public | |
23 | * License along with this library; if not, write to the Free Software | |
24 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA | |
cf77d1fa MD |
25 | * |
26 | * Include this file _after_ including your URCU flavor. | |
f0c29ed7 MD |
27 | */ |
28 | ||
674f7a69 | 29 | #include <stdint.h> |
6d320126 | 30 | #include <urcu/compiler.h> |
abc490a1 | 31 | #include <urcu-call-rcu.h> |
7b17c13e | 32 | #include <urcu-flavor.h> |
abc490a1 | 33 | |
01389791 MD |
34 | #ifdef __cplusplus |
35 | extern "C" { | |
36 | #endif | |
37 | ||
7f52427b | 38 | /* |
04db56f8 | 39 | * cds_lfht_node: Contains the next pointers and reverse-hash |
7f52427b | 40 | * value required for lookup and traversal of the hash table. |
04db56f8 | 41 | * |
db00ccc3 | 42 | * struct cds_lfht_node should be aligned on 8-bytes boundaries because |
13f656f9 MD |
43 | * the three lower bits are used as flags. It is worth noting that the |
44 | * information contained within these three bits could be represented on | |
45 | * two bits by re-using the same bit for REMOVAL_OWNER_FLAG and | |
46 | * BUCKET_FLAG. This can be done if we ensure that no iterator nor | |
47 | * updater check the BUCKET_FLAG after it detects that the REMOVED_FLAG | |
48 | * is set. Given the minimum size of struct cds_lfht_node is 8 bytes on | |
49 | * 32-bit architectures, we choose to go for simplicity and reserve | |
50 | * three bits. | |
7f52427b | 51 | * |
ae62aa6a MD |
52 | * struct cds_lfht_node can be embedded into a structure (as a field). |
53 | * caa_container_of() can be used to get the structure from the struct | |
54 | * cds_lfht_node after a lookup. | |
04db56f8 LJ |
55 | * |
56 | * The structure which embeds it typically holds the key (or key-value | |
57 | * pair) of the object. The caller code is responsible for calculation | |
58 | * of the hash value for cds_lfht APIs. | |
ae62aa6a | 59 | */ |
14044b37 | 60 | struct cds_lfht_node { |
3f2f3714 | 61 | struct cds_lfht_node *next; /* ptr | REMOVAL_OWNER_FLAG | BUCKET_FLAG | REMOVED_FLAG */ |
04db56f8 | 62 | unsigned long reverse_hash; |
db00ccc3 | 63 | } __attribute__((aligned(8))); |
abc490a1 | 64 | |
7f52427b | 65 | /* cds_lfht_iter: Used to track state while traversing a hash chain. */ |
adc0de68 MD |
66 | struct cds_lfht_iter { |
67 | struct cds_lfht_node *node, *next; | |
68 | }; | |
69 | ||
70 | static inline | |
71 | struct cds_lfht_node *cds_lfht_iter_get_node(struct cds_lfht_iter *iter) | |
72 | { | |
73 | return iter->node; | |
74 | } | |
75 | ||
14044b37 | 76 | struct cds_lfht; |
ab7d5fc6 | 77 | |
5e28c532 MD |
78 | /* |
79 | * Caution ! | |
abc490a1 | 80 | * Ensure reader and writer threads are registered as urcu readers. |
5e28c532 MD |
81 | */ |
82 | ||
996ff57c | 83 | typedef int (*cds_lfht_match_fct)(struct cds_lfht_node *node, const void *key); |
abc490a1 | 84 | |
f0c29ed7 | 85 | /* |
14044b37 | 86 | * cds_lfht_node_init - initialize a hash table node |
0422d92c | 87 | * @node: the node to initialize. |
04db56f8 LJ |
88 | * |
89 | * This function is kept to be eventually used for debugging purposes | |
90 | * (detection of memory corruption). | |
f0c29ed7 | 91 | */ |
abc490a1 | 92 | static inline |
04db56f8 | 93 | void cds_lfht_node_init(struct cds_lfht_node *node) |
abc490a1 | 94 | { |
abc490a1 | 95 | } |
674f7a69 | 96 | |
b8af5011 MD |
97 | /* |
98 | * Hash table creation flags. | |
99 | */ | |
100 | enum { | |
101 | CDS_LFHT_AUTO_RESIZE = (1U << 0), | |
5afadd12 | 102 | CDS_LFHT_ACCOUNTING = (1U << 1), |
b8af5011 MD |
103 | }; |
104 | ||
0b6aa001 LJ |
105 | struct cds_lfht_mm_type { |
106 | struct cds_lfht *(*alloc_cds_lfht)(unsigned long min_nr_alloc_buckets, | |
107 | unsigned long max_nr_buckets); | |
108 | void (*alloc_bucket_table)(struct cds_lfht *ht, unsigned long order); | |
109 | void (*free_bucket_table)(struct cds_lfht *ht, unsigned long order); | |
110 | struct cds_lfht_node *(*bucket_at)(struct cds_lfht *ht, | |
111 | unsigned long index); | |
112 | }; | |
113 | ||
114 | extern const struct cds_lfht_mm_type cds_lfht_mm_order; | |
308d1cb3 | 115 | extern const struct cds_lfht_mm_type cds_lfht_mm_chunk; |
b0b55251 | 116 | extern const struct cds_lfht_mm_type cds_lfht_mm_mmap; |
0b6aa001 | 117 | |
674f7a69 | 118 | /* |
7a9dcf9b | 119 | * _cds_lfht_new - API used by cds_lfht_new wrapper. Do not use directly. |
674f7a69 | 120 | */ |
b9c27904 | 121 | extern |
0422d92c | 122 | struct cds_lfht *_cds_lfht_new(unsigned long init_size, |
0722081a | 123 | unsigned long min_nr_alloc_buckets, |
747d725c | 124 | unsigned long max_nr_buckets, |
b8af5011 | 125 | int flags, |
0b6aa001 | 126 | const struct cds_lfht_mm_type *mm, |
7b17c13e | 127 | const struct rcu_flavor_struct *flavor, |
b7d619b0 | 128 | pthread_attr_t *attr); |
ab7d5fc6 | 129 | |
7a9dcf9b MD |
130 | /* |
131 | * cds_lfht_new - allocate a hash table. | |
747d725c LJ |
132 | * @init_size: number of buckets to allocate initially. Must be power of two. |
133 | * @min_nr_alloc_buckets: the minimum number of allocated buckets. | |
134 | * (must be power of two) | |
135 | * @max_nr_buckets: the maximum number of hash table buckets allowed. | |
136 | * (must be power of two) | |
f22dd01d MD |
137 | * @flags: hash table creation flags (can be combined with bitwise or: '|'). |
138 | * 0: no flags. | |
139 | * CDS_LFHT_AUTO_RESIZE: automatically resize hash table. | |
44bbe7fa LJ |
140 | * CDS_LFHT_ACCOUNTING: count the number of node addition |
141 | * and removal in the table | |
b7d619b0 | 142 | * @attr: optional resize worker thread attributes. NULL for default. |
7a9dcf9b | 143 | * |
7a9dcf9b MD |
144 | * Return NULL on error. |
145 | * Note: the RCU flavor must be already included before the hash table header. | |
b7d619b0 MD |
146 | * |
147 | * The programmer is responsible for ensuring that resize operation has a | |
148 | * priority equal to hash table updater threads. It should be performed by | |
149 | * specifying the appropriate priority in the pthread "attr" argument, and, | |
150 | * for CDS_LFHT_AUTO_RESIZE, by ensuring that call_rcu worker threads also have | |
151 | * this priority level. Having lower priority for call_rcu and resize threads | |
152 | * does not pose any correctness issue, but the resize operations could be | |
153 | * starved by updates, thus leading to long hash table bucket chains. | |
3a9c66db MD |
154 | * Threads calling cds_lfht_new are NOT required to be registered RCU |
155 | * read-side threads. It can be called very early. (e.g. before RCU is | |
156 | * initialized) | |
7a9dcf9b MD |
157 | */ |
158 | static inline | |
0422d92c | 159 | struct cds_lfht *cds_lfht_new(unsigned long init_size, |
0722081a | 160 | unsigned long min_nr_alloc_buckets, |
747d725c | 161 | unsigned long max_nr_buckets, |
b7d619b0 MD |
162 | int flags, |
163 | pthread_attr_t *attr) | |
7a9dcf9b | 164 | { |
7b17c13e | 165 | return _cds_lfht_new(init_size, min_nr_alloc_buckets, max_nr_buckets, |
c1888f3a | 166 | flags, NULL, &rcu_flavor, attr); |
7a9dcf9b MD |
167 | } |
168 | ||
f0c29ed7 | 169 | /* |
14044b37 | 170 | * cds_lfht_destroy - destroy a hash table. |
b7d619b0 MD |
171 | * @ht: the hash table to destroy. |
172 | * @attr: (output) resize worker thread attributes, as received by cds_lfht_new. | |
173 | * The caller will typically want to free this pointer if dynamically | |
7f52427b MD |
174 | * allocated. The attr point can be NULL if the caller does not |
175 | * need to be informed of the value passed to cds_lfht_new(). | |
6878c72b MD |
176 | * |
177 | * Return 0 on success, negative error value on error. | |
3df0c49c | 178 | * Threads calling this API need to be registered RCU read-side threads. |
96914388 MD |
179 | * cds_lfht_destroy should *not* be called from a RCU read-side critical |
180 | * section. | |
f0c29ed7 | 181 | */ |
b9c27904 | 182 | extern |
b7d619b0 | 183 | int cds_lfht_destroy(struct cds_lfht *ht, pthread_attr_t **attr); |
f0c29ed7 MD |
184 | |
185 | /* | |
14044b37 | 186 | * cds_lfht_count_nodes - count the number of nodes in the hash table. |
7f52427b | 187 | * @ht: the hash table. |
3a9c66db MD |
188 | * @split_count_before: sample the node count split-counter before traversal. |
189 | * @count: traverse the hash table, count the number of nodes observed. | |
190 | * @split_count_after: sample the node count split-counter after traversal. | |
0422d92c | 191 | * |
f0c29ed7 | 192 | * Call with rcu_read_lock held. |
3df0c49c | 193 | * Threads calling this API need to be registered RCU read-side threads. |
f0c29ed7 | 194 | */ |
b9c27904 | 195 | extern |
14044b37 | 196 | void cds_lfht_count_nodes(struct cds_lfht *ht, |
7f52427b | 197 | long *split_count_before, |
adc0de68 | 198 | unsigned long *count, |
7f52427b | 199 | long *split_count_after); |
ab7d5fc6 | 200 | |
f0c29ed7 | 201 | /* |
14044b37 | 202 | * cds_lfht_lookup - lookup a node by key. |
0422d92c | 203 | * @ht: the hash table. |
0422d92c | 204 | * @hash: the key hash. |
6f554439 LJ |
205 | * @match: the key match function. |
206 | * @key: the current node key. | |
3a9c66db | 207 | * @iter: node, if found (output). *iter->node set to NULL if not found. |
f0c29ed7 | 208 | * |
f0c29ed7 | 209 | * Call with rcu_read_lock held. |
3df0c49c | 210 | * Threads calling this API need to be registered RCU read-side threads. |
7b783f81 | 211 | * This function acts as a rcu_dereference() to read the node pointer. |
f0c29ed7 | 212 | */ |
b9c27904 | 213 | extern |
6f554439 | 214 | void cds_lfht_lookup(struct cds_lfht *ht, unsigned long hash, |
996ff57c | 215 | cds_lfht_match_fct match, const void *key, |
6f554439 | 216 | struct cds_lfht_iter *iter); |
ab7d5fc6 | 217 | |
f0c29ed7 | 218 | /* |
3a9c66db | 219 | * cds_lfht_next_duplicate - get the next item with same key, after iterator. |
0422d92c MD |
220 | * @ht: the hash table. |
221 | * @match: the key match function. | |
04db56f8 | 222 | * @key: the current node key. |
3a9c66db MD |
223 | * @iter: input: current iterator. |
224 | * output: node, if found. *iter->node set to NULL if not found. | |
f0c29ed7 | 225 | * |
3a9c66db MD |
226 | * Uses an iterator initialized by a lookup or traversal. Important: the |
227 | * iterator _needs_ to be initialized before calling | |
228 | * cds_lfht_next_duplicate. | |
adc0de68 MD |
229 | * Sets *iter-node to the following node with same key. |
230 | * Sets *iter->node to NULL if no following node exists with same key. | |
231 | * RCU read-side lock must be held across cds_lfht_lookup and | |
232 | * cds_lfht_next calls, and also between cds_lfht_next calls using the | |
233 | * node returned by a previous cds_lfht_next. | |
234 | * Call with rcu_read_lock held. | |
3df0c49c | 235 | * Threads calling this API need to be registered RCU read-side threads. |
7b783f81 | 236 | * This function acts as a rcu_dereference() to read the node pointer. |
f0c29ed7 | 237 | */ |
b9c27904 | 238 | extern |
0422d92c | 239 | void cds_lfht_next_duplicate(struct cds_lfht *ht, |
996ff57c | 240 | cds_lfht_match_fct match, const void *key, |
04db56f8 | 241 | struct cds_lfht_iter *iter); |
4e9b9fbf MD |
242 | |
243 | /* | |
244 | * cds_lfht_first - get the first node in the table. | |
0422d92c MD |
245 | * @ht: the hash table. |
246 | * @iter: First node, if exists (output). *iter->node set to NULL if not found. | |
4e9b9fbf MD |
247 | * |
248 | * Output in "*iter". *iter->node set to NULL if table is empty. | |
249 | * Call with rcu_read_lock held. | |
3df0c49c | 250 | * Threads calling this API need to be registered RCU read-side threads. |
7b783f81 | 251 | * This function acts as a rcu_dereference() to read the node pointer. |
4e9b9fbf | 252 | */ |
b9c27904 | 253 | extern |
4e9b9fbf MD |
254 | void cds_lfht_first(struct cds_lfht *ht, struct cds_lfht_iter *iter); |
255 | ||
256 | /* | |
257 | * cds_lfht_next - get the next node in the table. | |
0422d92c | 258 | * @ht: the hash table. |
3a9c66db MD |
259 | * @iter: input: current iterator. |
260 | * output: next node, if exists. *iter->node set to NULL if not found. | |
4e9b9fbf MD |
261 | * |
262 | * Input/Output in "*iter". *iter->node set to NULL if *iter was | |
263 | * pointing to the last table node. | |
264 | * Call with rcu_read_lock held. | |
3df0c49c | 265 | * Threads calling this API need to be registered RCU read-side threads. |
7b783f81 | 266 | * This function acts as a rcu_dereference() to read the node pointer. |
4e9b9fbf | 267 | */ |
b9c27904 | 268 | extern |
4e9b9fbf | 269 | void cds_lfht_next(struct cds_lfht *ht, struct cds_lfht_iter *iter); |
ab7d5fc6 | 270 | |
18117871 | 271 | /* |
14044b37 | 272 | * cds_lfht_add - add a node to the hash table. |
0422d92c MD |
273 | * @ht: the hash table. |
274 | * @hash: the key hash. | |
275 | * @node: the node to add. | |
f0c29ed7 | 276 | * |
48ed1c18 | 277 | * This function supports adding redundant keys into the table. |
3df0c49c MD |
278 | * Call with rcu_read_lock held. |
279 | * Threads calling this API need to be registered RCU read-side threads. | |
7b783f81 MD |
280 | * This function issues a full memory barrier before and after its |
281 | * atomic commit. | |
f0c29ed7 | 282 | */ |
b9c27904 | 283 | extern |
0422d92c MD |
284 | void cds_lfht_add(struct cds_lfht *ht, unsigned long hash, |
285 | struct cds_lfht_node *node); | |
f0c29ed7 MD |
286 | |
287 | /* | |
14044b37 | 288 | * cds_lfht_add_unique - add a node to hash table, if key is not present. |
0422d92c | 289 | * @ht: the hash table. |
6f554439 | 290 | * @hash: the node's hash. |
0422d92c | 291 | * @match: the key match function. |
04db56f8 | 292 | * @key: the node's key. |
0422d92c | 293 | * @node: the node to try adding. |
f0c29ed7 | 294 | * |
6878c72b | 295 | * Return the node added upon success. |
860d07e8 MD |
296 | * Return the unique node already present upon failure. If |
297 | * cds_lfht_add_unique fails, the node passed as parameter should be | |
3a9c66db MD |
298 | * freed by the caller. In this case, the caller does NOT need to wait |
299 | * for a grace period before freeing the node. | |
f0c29ed7 | 300 | * Call with rcu_read_lock held. |
3df0c49c | 301 | * Threads calling this API need to be registered RCU read-side threads. |
48ed1c18 MD |
302 | * |
303 | * The semantic of this function is that if only this function is used | |
304 | * to add keys into the table, no duplicated keys should ever be | |
305 | * observable in the table. The same guarantee apply for combination of | |
9357c415 | 306 | * add_unique and add_replace (see below). |
7b783f81 MD |
307 | * |
308 | * Upon success, this function issues a full memory barrier before and | |
309 | * after its atomic commit. Upon failure, this function acts like a | |
310 | * simple lookup operation: it acts as a rcu_dereference() to read the | |
311 | * node pointer. The failure case does not guarantee any other memory | |
312 | * barrier. | |
18117871 | 313 | */ |
b9c27904 | 314 | extern |
adc0de68 | 315 | struct cds_lfht_node *cds_lfht_add_unique(struct cds_lfht *ht, |
6f554439 | 316 | unsigned long hash, |
0422d92c | 317 | cds_lfht_match_fct match, |
996ff57c | 318 | const void *key, |
adc0de68 | 319 | struct cds_lfht_node *node); |
3eca1b8c | 320 | |
48ed1c18 | 321 | /* |
9357c415 | 322 | * cds_lfht_add_replace - replace or add a node within hash table. |
0422d92c | 323 | * @ht: the hash table. |
6f554439 | 324 | * @hash: the node's hash. |
0422d92c | 325 | * @match: the key match function. |
04db56f8 | 326 | * @key: the node's key. |
0422d92c | 327 | * @node: the node to add. |
48ed1c18 MD |
328 | * |
329 | * Return the node replaced upon success. If no node matching the key | |
330 | * was present, return NULL, which also means the operation succeeded. | |
331 | * This replacement operation should never fail. | |
332 | * Call with rcu_read_lock held. | |
3df0c49c | 333 | * Threads calling this API need to be registered RCU read-side threads. |
48ed1c18 MD |
334 | * After successful replacement, a grace period must be waited for before |
335 | * freeing the memory reserved for the returned node. | |
336 | * | |
3a9c66db MD |
337 | * The semantic of replacement vs lookups and traversals is the |
338 | * following: if lookups and traversals are performed between a key | |
339 | * unique insertion and its removal, we guarantee that the lookups and | |
340 | * traversals will always find exactly one instance of the key if it is | |
341 | * replaced concurrently with the lookups. | |
48ed1c18 MD |
342 | * |
343 | * Providing this semantic allows us to ensure that replacement-only | |
344 | * schemes will never generate duplicated keys. It also allows us to | |
9357c415 | 345 | * guarantee that a combination of add_replace and add_unique updates |
48ed1c18 | 346 | * will never generate duplicated keys. |
7b783f81 MD |
347 | * |
348 | * This function issues a full memory barrier before and after its | |
349 | * atomic commit. | |
48ed1c18 | 350 | */ |
b9c27904 | 351 | extern |
9357c415 | 352 | struct cds_lfht_node *cds_lfht_add_replace(struct cds_lfht *ht, |
6f554439 | 353 | unsigned long hash, |
0422d92c | 354 | cds_lfht_match_fct match, |
996ff57c | 355 | const void *key, |
adc0de68 | 356 | struct cds_lfht_node *node); |
48ed1c18 | 357 | |
f0c29ed7 | 358 | /* |
929ad508 | 359 | * cds_lfht_replace - replace a node pointed to by iter within hash table. |
0422d92c MD |
360 | * @ht: the hash table. |
361 | * @old_iter: the iterator position of the node to replace. | |
2e79c445 MD |
362 | * @hash: the node's hash. |
363 | * @match: the key match function. | |
364 | * @key: the node's key. | |
365 | * @new_node: the new node to use as replacement. | |
f0c29ed7 | 366 | * |
9357c415 | 367 | * Return 0 if replacement is successful, negative value otherwise. |
2e79c445 MD |
368 | * Replacing a NULL old node or an already removed node will fail with |
369 | * -ENOENT. | |
370 | * If the hash or value of the node to replace and the new node differ, | |
371 | * this function returns -EINVAL without proceeding to the replacement. | |
9357c415 MD |
372 | * Old node can be looked up with cds_lfht_lookup and cds_lfht_next. |
373 | * RCU read-side lock must be held between lookup and replacement. | |
374 | * Call with rcu_read_lock held. | |
3df0c49c | 375 | * Threads calling this API need to be registered RCU read-side threads. |
9357c415 MD |
376 | * After successful replacement, a grace period must be waited for before |
377 | * freeing the memory reserved for the old node (which can be accessed | |
378 | * with cds_lfht_iter_get_node). | |
379 | * | |
3a9c66db MD |
380 | * The semantic of replacement vs lookups is the same as |
381 | * cds_lfht_add_replace(). | |
7b783f81 MD |
382 | * |
383 | * Upon success, this function issues a full memory barrier before and | |
384 | * after its atomic commit. Upon failure, this function does not issue | |
385 | * any memory barrier. | |
9357c415 | 386 | */ |
b9c27904 | 387 | extern |
2e79c445 MD |
388 | int cds_lfht_replace(struct cds_lfht *ht, |
389 | struct cds_lfht_iter *old_iter, | |
390 | unsigned long hash, | |
391 | cds_lfht_match_fct match, | |
392 | const void *key, | |
9357c415 MD |
393 | struct cds_lfht_node *new_node); |
394 | ||
395 | /* | |
396 | * cds_lfht_del - remove node pointed to by iterator from hash table. | |
0422d92c | 397 | * @ht: the hash table. |
bc8c3c74 | 398 | * @node: the node to delete. |
9357c415 MD |
399 | * |
400 | * Return 0 if the node is successfully removed, negative value | |
401 | * otherwise. | |
bc8c3c74 | 402 | * Deleting a NULL node or an already removed node will fail with a |
9357c415 | 403 | * negative value. |
bc8c3c74 MD |
404 | * Node can be looked up with cds_lfht_lookup and cds_lfht_next, |
405 | * followed by use of cds_lfht_iter_get_node. | |
9357c415 | 406 | * RCU read-side lock must be held between lookup and removal. |
f0c29ed7 | 407 | * Call with rcu_read_lock held. |
3df0c49c | 408 | * Threads calling this API need to be registered RCU read-side threads. |
48ed1c18 | 409 | * After successful removal, a grace period must be waited for before |
9357c415 MD |
410 | * freeing the memory reserved for old node (which can be accessed with |
411 | * cds_lfht_iter_get_node). | |
7b783f81 MD |
412 | * Upon success, this function issues a full memory barrier before and |
413 | * after its atomic commit. Upon failure, this function does not issue | |
414 | * any memory barrier. | |
f0c29ed7 | 415 | */ |
b9c27904 | 416 | extern |
bc8c3c74 | 417 | int cds_lfht_del(struct cds_lfht *ht, struct cds_lfht_node *node); |
ab7d5fc6 | 418 | |
df55172a | 419 | /* |
3a9c66db | 420 | * cds_lfht_is_node_deleted - query whether a node is removed from hash table. |
df55172a MD |
421 | * |
422 | * Return non-zero if the node is deleted from the hash table, 0 | |
423 | * otherwise. | |
424 | * Node can be looked up with cds_lfht_lookup and cds_lfht_next, | |
425 | * followed by use of cds_lfht_iter_get_node. | |
426 | * RCU read-side lock must be held between lookup and call to this | |
427 | * function. | |
428 | * Call with rcu_read_lock held. | |
429 | * Threads calling this API need to be registered RCU read-side threads. | |
7b783f81 | 430 | * This function does not issue any memory barrier. |
df55172a | 431 | */ |
b9c27904 | 432 | extern |
df55172a MD |
433 | int cds_lfht_is_node_deleted(struct cds_lfht_node *node); |
434 | ||
f0c29ed7 | 435 | /* |
14044b37 | 436 | * cds_lfht_resize - Force a hash table resize |
0422d92c | 437 | * @ht: the hash table. |
1475579c | 438 | * @new_size: update to this hash table size. |
3df0c49c MD |
439 | * |
440 | * Threads calling this API need to be registered RCU read-side threads. | |
7b783f81 | 441 | * This function does not (necessarily) issue memory barriers. |
43387742 MD |
442 | * cds_lfht_resize should *not* be called from a RCU read-side critical |
443 | * section. | |
f0c29ed7 | 444 | */ |
b9c27904 | 445 | extern |
1475579c | 446 | void cds_lfht_resize(struct cds_lfht *ht, unsigned long new_size); |
464a1ec9 | 447 | |
6d320126 | 448 | /* |
3a9c66db MD |
449 | * Note: it is safe to perform element removal (del), replacement, or |
450 | * any hash table update operation during any of the following hash | |
451 | * table traversals. | |
7b783f81 | 452 | * These functions act as rcu_dereference() to read the node pointers. |
6d320126 MD |
453 | */ |
454 | #define cds_lfht_for_each(ht, iter, node) \ | |
455 | for (cds_lfht_first(ht, iter), \ | |
456 | node = cds_lfht_iter_get_node(iter); \ | |
457 | node != NULL; \ | |
458 | cds_lfht_next(ht, iter), \ | |
459 | node = cds_lfht_iter_get_node(iter)) | |
460 | ||
6f554439 LJ |
461 | #define cds_lfht_for_each_duplicate(ht, hash, match, key, iter, node) \ |
462 | for (cds_lfht_lookup(ht, hash, match, key, iter), \ | |
6d320126 MD |
463 | node = cds_lfht_iter_get_node(iter); \ |
464 | node != NULL; \ | |
465 | cds_lfht_next_duplicate(ht, match, key, iter), \ | |
466 | node = cds_lfht_iter_get_node(iter)) | |
467 | ||
468 | #define cds_lfht_for_each_entry(ht, iter, pos, member) \ | |
469 | for (cds_lfht_first(ht, iter), \ | |
470 | pos = caa_container_of(cds_lfht_iter_get_node(iter), \ | |
bdffa73a | 471 | __typeof__(*(pos)), member); \ |
0b0627bf | 472 | &(pos)->member != NULL; \ |
6d320126 MD |
473 | cds_lfht_next(ht, iter), \ |
474 | pos = caa_container_of(cds_lfht_iter_get_node(iter), \ | |
bdffa73a | 475 | __typeof__(*(pos)), member)) |
6d320126 | 476 | |
6f554439 | 477 | #define cds_lfht_for_each_entry_duplicate(ht, hash, match, key, \ |
6d320126 | 478 | iter, pos, member) \ |
6f554439 | 479 | for (cds_lfht_lookup(ht, hash, match, key, iter), \ |
6d320126 | 480 | pos = caa_container_of(cds_lfht_iter_get_node(iter), \ |
bdffa73a | 481 | __typeof__(*(pos)), member); \ |
0b0627bf | 482 | &(pos)->member != NULL; \ |
6d320126 MD |
483 | cds_lfht_next_duplicate(ht, match, key, iter), \ |
484 | pos = caa_container_of(cds_lfht_iter_get_node(iter), \ | |
bdffa73a | 485 | __typeof__(*(pos)), member)) |
6d320126 | 486 | |
01389791 MD |
487 | #ifdef __cplusplus |
488 | } | |
489 | #endif | |
490 | ||
a42cc659 | 491 | #endif /* _URCU_RCULFHASH_H */ |