cds_lfht_is_node_deleted parameter can be marked const
[urcu.git] / include / urcu / rculfhash.h
CommitLineData
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 25 *
938465b4
MD
26 * For use with URCU_API_MAP (API mapping of liburcu), include this file
27 * _after_ including your URCU flavor.
f0c29ed7
MD
28 */
29
d7c76f85 30#include <urcu/config.h>
674f7a69 31#include <stdint.h>
6bcce235 32#include <pthread.h>
6d320126 33#include <urcu/compiler.h>
abc490a1 34
01389791
MD
35#ifdef __cplusplus
36extern "C" {
37#endif
38
d7c76f85
MD
39struct cds_lfht;
40
7f52427b 41/*
04db56f8 42 * cds_lfht_node: Contains the next pointers and reverse-hash
7f52427b 43 * value required for lookup and traversal of the hash table.
04db56f8 44 *
db00ccc3 45 * struct cds_lfht_node should be aligned on 8-bytes boundaries because
13f656f9
MD
46 * the three lower bits are used as flags. It is worth noting that the
47 * information contained within these three bits could be represented on
48 * two bits by re-using the same bit for REMOVAL_OWNER_FLAG and
49 * BUCKET_FLAG. This can be done if we ensure that no iterator nor
50 * updater check the BUCKET_FLAG after it detects that the REMOVED_FLAG
51 * is set. Given the minimum size of struct cds_lfht_node is 8 bytes on
52 * 32-bit architectures, we choose to go for simplicity and reserve
53 * three bits.
7f52427b 54 *
ae62aa6a
MD
55 * struct cds_lfht_node can be embedded into a structure (as a field).
56 * caa_container_of() can be used to get the structure from the struct
57 * cds_lfht_node after a lookup.
04db56f8
LJ
58 *
59 * The structure which embeds it typically holds the key (or key-value
60 * pair) of the object. The caller code is responsible for calculation
61 * of the hash value for cds_lfht APIs.
ae62aa6a 62 */
14044b37 63struct cds_lfht_node {
3f2f3714 64 struct cds_lfht_node *next; /* ptr | REMOVAL_OWNER_FLAG | BUCKET_FLAG | REMOVED_FLAG */
04db56f8 65 unsigned long reverse_hash;
db00ccc3 66} __attribute__((aligned(8)));
abc490a1 67
7f52427b 68/* cds_lfht_iter: Used to track state while traversing a hash chain. */
adc0de68
MD
69struct cds_lfht_iter {
70 struct cds_lfht_node *node, *next;
d7c76f85
MD
71 /*
72 * For debugging purposes, build both API users and rculfhash
73 * library with CDS_LFHT_ITER_DEBUG defined. This enables extra
74 * consistency checks for calls to a cds_lfht_next() or
75 * cds_lfht_next_duplicate() after the iterator has been
76 * re-purposed to iterate on a different hash table. This is a
77 * common programming mistake when performing hash table lookup
78 * nested in a hash table traversal.
79 */
80#ifdef CONFIG_CDS_LFHT_ITER_DEBUG
81 struct cds_lfht *lfht;
82#endif
adc0de68
MD
83};
84
85static inline
86struct cds_lfht_node *cds_lfht_iter_get_node(struct cds_lfht_iter *iter)
87{
88 return iter->node;
89}
90
938465b4 91struct rcu_flavor_struct;
ab7d5fc6 92
5e28c532
MD
93/*
94 * Caution !
abc490a1 95 * Ensure reader and writer threads are registered as urcu readers.
5e28c532
MD
96 */
97
996ff57c 98typedef int (*cds_lfht_match_fct)(struct cds_lfht_node *node, const void *key);
abc490a1 99
f0c29ed7 100/*
14044b37 101 * cds_lfht_node_init - initialize a hash table node
0422d92c 102 * @node: the node to initialize.
04db56f8
LJ
103 *
104 * This function is kept to be eventually used for debugging purposes
105 * (detection of memory corruption).
f0c29ed7 106 */
abc490a1 107static inline
04db56f8 108void cds_lfht_node_init(struct cds_lfht_node *node)
abc490a1 109{
abc490a1 110}
674f7a69 111
b8af5011
MD
112/*
113 * Hash table creation flags.
114 */
115enum {
116 CDS_LFHT_AUTO_RESIZE = (1U << 0),
5afadd12 117 CDS_LFHT_ACCOUNTING = (1U << 1),
b8af5011
MD
118};
119
0b6aa001
LJ
120struct cds_lfht_mm_type {
121 struct cds_lfht *(*alloc_cds_lfht)(unsigned long min_nr_alloc_buckets,
122 unsigned long max_nr_buckets);
123 void (*alloc_bucket_table)(struct cds_lfht *ht, unsigned long order);
124 void (*free_bucket_table)(struct cds_lfht *ht, unsigned long order);
125 struct cds_lfht_node *(*bucket_at)(struct cds_lfht *ht,
126 unsigned long index);
127};
128
129extern const struct cds_lfht_mm_type cds_lfht_mm_order;
308d1cb3 130extern const struct cds_lfht_mm_type cds_lfht_mm_chunk;
b0b55251 131extern const struct cds_lfht_mm_type cds_lfht_mm_mmap;
0b6aa001 132
674f7a69 133/*
7a9dcf9b 134 * _cds_lfht_new - API used by cds_lfht_new wrapper. Do not use directly.
674f7a69 135 */
b9c27904 136extern
0422d92c 137struct cds_lfht *_cds_lfht_new(unsigned long init_size,
0722081a 138 unsigned long min_nr_alloc_buckets,
747d725c 139 unsigned long max_nr_buckets,
b8af5011 140 int flags,
0b6aa001 141 const struct cds_lfht_mm_type *mm,
7b17c13e 142 const struct rcu_flavor_struct *flavor,
b7d619b0 143 pthread_attr_t *attr);
ab7d5fc6 144
938465b4
MD
145/*
146 * cds_lfht_new_flavor - allocate a hash table tied to a RCU flavor.
147 * @init_size: number of buckets to allocate initially. Must be power of two.
148 * @min_nr_alloc_buckets: the minimum number of allocated buckets.
149 * (must be power of two)
150 * @max_nr_buckets: the maximum number of hash table buckets allowed.
151 * (must be power of two, 0 is accepted, means
152 * "infinite")
153 * @flavor: flavor of liburcu to use to synchronize the hash table
154 * @flags: hash table creation flags (can be combined with bitwise or: '|').
155 * 0: no flags.
156 * CDS_LFHT_AUTO_RESIZE: automatically resize hash table.
157 * CDS_LFHT_ACCOUNTING: count the number of node addition
158 * and removal in the table
159 * @attr: optional resize worker thread attributes. NULL for default.
160 *
161 * Return NULL on error.
162 * Note: the RCU flavor must be already included before the hash table header.
163 *
164 * The programmer is responsible for ensuring that resize operation has a
165 * priority equal to hash table updater threads. It should be performed by
166 * specifying the appropriate priority in the pthread "attr" argument, and,
167 * for CDS_LFHT_AUTO_RESIZE, by ensuring that call_rcu worker threads also have
168 * this priority level. Having lower priority for call_rcu and resize threads
169 * does not pose any correctness issue, but the resize operations could be
170 * starved by updates, thus leading to long hash table bucket chains.
171 * Threads calling cds_lfht_new are NOT required to be registered RCU
172 * read-side threads. It can be called very early. (e.g. before RCU is
173 * initialized)
174 */
175static inline
176struct cds_lfht *cds_lfht_new_flavor(unsigned long init_size,
177 unsigned long min_nr_alloc_buckets,
178 unsigned long max_nr_buckets,
179 int flags,
180 const struct rcu_flavor_struct *flavor,
181 pthread_attr_t *attr)
182{
183 return _cds_lfht_new(init_size, min_nr_alloc_buckets, max_nr_buckets,
184 flags, NULL, flavor, attr);
185}
186
187
188#ifdef URCU_API_MAP
7a9dcf9b
MD
189/*
190 * cds_lfht_new - allocate a hash table.
747d725c
LJ
191 * @init_size: number of buckets to allocate initially. Must be power of two.
192 * @min_nr_alloc_buckets: the minimum number of allocated buckets.
193 * (must be power of two)
194 * @max_nr_buckets: the maximum number of hash table buckets allowed.
28d5c1b5
MD
195 * (must be power of two, 0 is accepted, means
196 * "infinite")
f22dd01d
MD
197 * @flags: hash table creation flags (can be combined with bitwise or: '|').
198 * 0: no flags.
199 * CDS_LFHT_AUTO_RESIZE: automatically resize hash table.
44bbe7fa
LJ
200 * CDS_LFHT_ACCOUNTING: count the number of node addition
201 * and removal in the table
b7d619b0 202 * @attr: optional resize worker thread attributes. NULL for default.
7a9dcf9b 203 *
7a9dcf9b
MD
204 * Return NULL on error.
205 * Note: the RCU flavor must be already included before the hash table header.
b7d619b0
MD
206 *
207 * The programmer is responsible for ensuring that resize operation has a
208 * priority equal to hash table updater threads. It should be performed by
209 * specifying the appropriate priority in the pthread "attr" argument, and,
210 * for CDS_LFHT_AUTO_RESIZE, by ensuring that call_rcu worker threads also have
211 * this priority level. Having lower priority for call_rcu and resize threads
212 * does not pose any correctness issue, but the resize operations could be
213 * starved by updates, thus leading to long hash table bucket chains.
3a9c66db
MD
214 * Threads calling cds_lfht_new are NOT required to be registered RCU
215 * read-side threads. It can be called very early. (e.g. before RCU is
216 * initialized)
7a9dcf9b
MD
217 */
218static inline
0422d92c 219struct cds_lfht *cds_lfht_new(unsigned long init_size,
0722081a 220 unsigned long min_nr_alloc_buckets,
747d725c 221 unsigned long max_nr_buckets,
b7d619b0
MD
222 int flags,
223 pthread_attr_t *attr)
7a9dcf9b 224{
7b17c13e 225 return _cds_lfht_new(init_size, min_nr_alloc_buckets, max_nr_buckets,
c1888f3a 226 flags, NULL, &rcu_flavor, attr);
7a9dcf9b 227}
938465b4 228#endif /* URCU_API_MAP */
7a9dcf9b 229
f0c29ed7 230/*
14044b37 231 * cds_lfht_destroy - destroy a hash table.
b7d619b0
MD
232 * @ht: the hash table to destroy.
233 * @attr: (output) resize worker thread attributes, as received by cds_lfht_new.
234 * The caller will typically want to free this pointer if dynamically
7f52427b
MD
235 * allocated. The attr point can be NULL if the caller does not
236 * need to be informed of the value passed to cds_lfht_new().
6878c72b
MD
237 *
238 * Return 0 on success, negative error value on error.
d0ec0ed2
MD
239
240 * Prior to liburcu 0.10:
241 * - Threads calling this API need to be registered RCU read-side
242 * threads.
243 * - cds_lfht_destroy should *not* be called from a RCU read-side
244 * critical section. It should *not* be called from a call_rcu thread
245 * context neither.
246 *
247 * Starting from liburcu 0.10, rculfhash implements its own worker
248 * thread to handle resize operations, which removes RCU requirements on
249 * cds_lfht_destroy.
f0c29ed7 250 */
b9c27904 251extern
b7d619b0 252int cds_lfht_destroy(struct cds_lfht *ht, pthread_attr_t **attr);
f0c29ed7
MD
253
254/*
14044b37 255 * cds_lfht_count_nodes - count the number of nodes in the hash table.
7f52427b 256 * @ht: the hash table.
3a9c66db
MD
257 * @split_count_before: sample the node count split-counter before traversal.
258 * @count: traverse the hash table, count the number of nodes observed.
259 * @split_count_after: sample the node count split-counter after traversal.
0422d92c 260 *
f0c29ed7 261 * Call with rcu_read_lock held.
3df0c49c 262 * Threads calling this API need to be registered RCU read-side threads.
f0c29ed7 263 */
b9c27904 264extern
14044b37 265void cds_lfht_count_nodes(struct cds_lfht *ht,
7f52427b 266 long *split_count_before,
adc0de68 267 unsigned long *count,
7f52427b 268 long *split_count_after);
ab7d5fc6 269
f0c29ed7 270/*
14044b37 271 * cds_lfht_lookup - lookup a node by key.
0422d92c 272 * @ht: the hash table.
0422d92c 273 * @hash: the key hash.
6f554439
LJ
274 * @match: the key match function.
275 * @key: the current node key.
3a9c66db 276 * @iter: node, if found (output). *iter->node set to NULL if not found.
f0c29ed7 277 *
f0c29ed7 278 * Call with rcu_read_lock held.
3df0c49c 279 * Threads calling this API need to be registered RCU read-side threads.
7b783f81 280 * This function acts as a rcu_dereference() to read the node pointer.
f0c29ed7 281 */
b9c27904 282extern
6f554439 283void cds_lfht_lookup(struct cds_lfht *ht, unsigned long hash,
996ff57c 284 cds_lfht_match_fct match, const void *key,
6f554439 285 struct cds_lfht_iter *iter);
ab7d5fc6 286
f0c29ed7 287/*
3a9c66db 288 * cds_lfht_next_duplicate - get the next item with same key, after iterator.
0422d92c
MD
289 * @ht: the hash table.
290 * @match: the key match function.
04db56f8 291 * @key: the current node key.
3a9c66db
MD
292 * @iter: input: current iterator.
293 * output: node, if found. *iter->node set to NULL if not found.
f0c29ed7 294 *
3a9c66db
MD
295 * Uses an iterator initialized by a lookup or traversal. Important: the
296 * iterator _needs_ to be initialized before calling
297 * cds_lfht_next_duplicate.
adc0de68
MD
298 * Sets *iter-node to the following node with same key.
299 * Sets *iter->node to NULL if no following node exists with same key.
300 * RCU read-side lock must be held across cds_lfht_lookup and
301 * cds_lfht_next calls, and also between cds_lfht_next calls using the
302 * node returned by a previous cds_lfht_next.
303 * Call with rcu_read_lock held.
3df0c49c 304 * Threads calling this API need to be registered RCU read-side threads.
7b783f81 305 * This function acts as a rcu_dereference() to read the node pointer.
f0c29ed7 306 */
b9c27904 307extern
0422d92c 308void cds_lfht_next_duplicate(struct cds_lfht *ht,
996ff57c 309 cds_lfht_match_fct match, const void *key,
04db56f8 310 struct cds_lfht_iter *iter);
4e9b9fbf
MD
311
312/*
313 * cds_lfht_first - get the first node in the table.
0422d92c
MD
314 * @ht: the hash table.
315 * @iter: First node, if exists (output). *iter->node set to NULL if not found.
4e9b9fbf
MD
316 *
317 * Output in "*iter". *iter->node set to NULL if table is empty.
318 * Call with rcu_read_lock held.
3df0c49c 319 * Threads calling this API need to be registered RCU read-side threads.
7b783f81 320 * This function acts as a rcu_dereference() to read the node pointer.
4e9b9fbf 321 */
b9c27904 322extern
4e9b9fbf
MD
323void cds_lfht_first(struct cds_lfht *ht, struct cds_lfht_iter *iter);
324
325/*
326 * cds_lfht_next - get the next node in the table.
0422d92c 327 * @ht: the hash table.
3a9c66db
MD
328 * @iter: input: current iterator.
329 * output: next node, if exists. *iter->node set to NULL if not found.
4e9b9fbf
MD
330 *
331 * Input/Output in "*iter". *iter->node set to NULL if *iter was
332 * pointing to the last table node.
333 * Call with rcu_read_lock held.
3df0c49c 334 * Threads calling this API need to be registered RCU read-side threads.
7b783f81 335 * This function acts as a rcu_dereference() to read the node pointer.
4e9b9fbf 336 */
b9c27904 337extern
4e9b9fbf 338void cds_lfht_next(struct cds_lfht *ht, struct cds_lfht_iter *iter);
ab7d5fc6 339
18117871 340/*
14044b37 341 * cds_lfht_add - add a node to the hash table.
0422d92c
MD
342 * @ht: the hash table.
343 * @hash: the key hash.
344 * @node: the node to add.
f0c29ed7 345 *
48ed1c18 346 * This function supports adding redundant keys into the table.
3df0c49c
MD
347 * Call with rcu_read_lock held.
348 * Threads calling this API need to be registered RCU read-side threads.
7b783f81
MD
349 * This function issues a full memory barrier before and after its
350 * atomic commit.
f0c29ed7 351 */
b9c27904 352extern
0422d92c
MD
353void cds_lfht_add(struct cds_lfht *ht, unsigned long hash,
354 struct cds_lfht_node *node);
f0c29ed7
MD
355
356/*
14044b37 357 * cds_lfht_add_unique - add a node to hash table, if key is not present.
0422d92c 358 * @ht: the hash table.
6f554439 359 * @hash: the node's hash.
0422d92c 360 * @match: the key match function.
04db56f8 361 * @key: the node's key.
0422d92c 362 * @node: the node to try adding.
f0c29ed7 363 *
6878c72b 364 * Return the node added upon success.
860d07e8
MD
365 * Return the unique node already present upon failure. If
366 * cds_lfht_add_unique fails, the node passed as parameter should be
3a9c66db 367 * freed by the caller. In this case, the caller does NOT need to wait
50024344 368 * for a grace period before freeing or re-using the node.
f0c29ed7 369 * Call with rcu_read_lock held.
3df0c49c 370 * Threads calling this API need to be registered RCU read-side threads.
48ed1c18
MD
371 *
372 * The semantic of this function is that if only this function is used
373 * to add keys into the table, no duplicated keys should ever be
374 * observable in the table. The same guarantee apply for combination of
9357c415 375 * add_unique and add_replace (see below).
7b783f81
MD
376 *
377 * Upon success, this function issues a full memory barrier before and
378 * after its atomic commit. Upon failure, this function acts like a
379 * simple lookup operation: it acts as a rcu_dereference() to read the
380 * node pointer. The failure case does not guarantee any other memory
381 * barrier.
18117871 382 */
b9c27904 383extern
adc0de68 384struct cds_lfht_node *cds_lfht_add_unique(struct cds_lfht *ht,
6f554439 385 unsigned long hash,
0422d92c 386 cds_lfht_match_fct match,
996ff57c 387 const void *key,
adc0de68 388 struct cds_lfht_node *node);
3eca1b8c 389
48ed1c18 390/*
9357c415 391 * cds_lfht_add_replace - replace or add a node within hash table.
0422d92c 392 * @ht: the hash table.
6f554439 393 * @hash: the node's hash.
0422d92c 394 * @match: the key match function.
04db56f8 395 * @key: the node's key.
0422d92c 396 * @node: the node to add.
48ed1c18
MD
397 *
398 * Return the node replaced upon success. If no node matching the key
399 * was present, return NULL, which also means the operation succeeded.
400 * This replacement operation should never fail.
401 * Call with rcu_read_lock held.
3df0c49c 402 * Threads calling this API need to be registered RCU read-side threads.
48ed1c18 403 * After successful replacement, a grace period must be waited for before
50024344 404 * freeing or re-using the memory reserved for the returned node.
48ed1c18 405 *
3a9c66db
MD
406 * The semantic of replacement vs lookups and traversals is the
407 * following: if lookups and traversals are performed between a key
408 * unique insertion and its removal, we guarantee that the lookups and
409 * traversals will always find exactly one instance of the key if it is
410 * replaced concurrently with the lookups.
48ed1c18
MD
411 *
412 * Providing this semantic allows us to ensure that replacement-only
413 * schemes will never generate duplicated keys. It also allows us to
9357c415 414 * guarantee that a combination of add_replace and add_unique updates
48ed1c18 415 * will never generate duplicated keys.
7b783f81
MD
416 *
417 * This function issues a full memory barrier before and after its
418 * atomic commit.
48ed1c18 419 */
b9c27904 420extern
9357c415 421struct cds_lfht_node *cds_lfht_add_replace(struct cds_lfht *ht,
6f554439 422 unsigned long hash,
0422d92c 423 cds_lfht_match_fct match,
996ff57c 424 const void *key,
adc0de68 425 struct cds_lfht_node *node);
48ed1c18 426
f0c29ed7 427/*
929ad508 428 * cds_lfht_replace - replace a node pointed to by iter within hash table.
0422d92c
MD
429 * @ht: the hash table.
430 * @old_iter: the iterator position of the node to replace.
2e79c445
MD
431 * @hash: the node's hash.
432 * @match: the key match function.
433 * @key: the node's key.
434 * @new_node: the new node to use as replacement.
f0c29ed7 435 *
9357c415 436 * Return 0 if replacement is successful, negative value otherwise.
2e79c445
MD
437 * Replacing a NULL old node or an already removed node will fail with
438 * -ENOENT.
439 * If the hash or value of the node to replace and the new node differ,
440 * this function returns -EINVAL without proceeding to the replacement.
9357c415
MD
441 * Old node can be looked up with cds_lfht_lookup and cds_lfht_next.
442 * RCU read-side lock must be held between lookup and replacement.
443 * Call with rcu_read_lock held.
3df0c49c 444 * Threads calling this API need to be registered RCU read-side threads.
9357c415 445 * After successful replacement, a grace period must be waited for before
50024344
MD
446 * freeing or re-using the memory reserved for the old node (which can
447 * be accessed with cds_lfht_iter_get_node).
9357c415 448 *
3a9c66db
MD
449 * The semantic of replacement vs lookups is the same as
450 * cds_lfht_add_replace().
7b783f81
MD
451 *
452 * Upon success, this function issues a full memory barrier before and
453 * after its atomic commit. Upon failure, this function does not issue
454 * any memory barrier.
9357c415 455 */
b9c27904 456extern
2e79c445
MD
457int cds_lfht_replace(struct cds_lfht *ht,
458 struct cds_lfht_iter *old_iter,
459 unsigned long hash,
460 cds_lfht_match_fct match,
461 const void *key,
9357c415
MD
462 struct cds_lfht_node *new_node);
463
464/*
465 * cds_lfht_del - remove node pointed to by iterator from hash table.
0422d92c 466 * @ht: the hash table.
bc8c3c74 467 * @node: the node to delete.
9357c415
MD
468 *
469 * Return 0 if the node is successfully removed, negative value
470 * otherwise.
bc8c3c74 471 * Deleting a NULL node or an already removed node will fail with a
9357c415 472 * negative value.
bc8c3c74
MD
473 * Node can be looked up with cds_lfht_lookup and cds_lfht_next,
474 * followed by use of cds_lfht_iter_get_node.
9357c415 475 * RCU read-side lock must be held between lookup and removal.
f0c29ed7 476 * Call with rcu_read_lock held.
3df0c49c 477 * Threads calling this API need to be registered RCU read-side threads.
48ed1c18 478 * After successful removal, a grace period must be waited for before
50024344
MD
479 * freeing or re-using the memory reserved for old node (which can be
480 * accessed with cds_lfht_iter_get_node).
7b783f81
MD
481 * Upon success, this function issues a full memory barrier before and
482 * after its atomic commit. Upon failure, this function does not issue
483 * any memory barrier.
f0c29ed7 484 */
b9c27904 485extern
bc8c3c74 486int cds_lfht_del(struct cds_lfht *ht, struct cds_lfht_node *node);
ab7d5fc6 487
df55172a 488/*
3a9c66db 489 * cds_lfht_is_node_deleted - query whether a node is removed from hash table.
df55172a
MD
490 *
491 * Return non-zero if the node is deleted from the hash table, 0
492 * otherwise.
493 * Node can be looked up with cds_lfht_lookup and cds_lfht_next,
494 * followed by use of cds_lfht_iter_get_node.
495 * RCU read-side lock must be held between lookup and call to this
496 * function.
497 * Call with rcu_read_lock held.
498 * Threads calling this API need to be registered RCU read-side threads.
7b783f81 499 * This function does not issue any memory barrier.
df55172a 500 */
b9c27904 501extern
afa5940d 502int cds_lfht_is_node_deleted(const struct cds_lfht_node *node);
df55172a 503
f0c29ed7 504/*
14044b37 505 * cds_lfht_resize - Force a hash table resize
0422d92c 506 * @ht: the hash table.
1475579c 507 * @new_size: update to this hash table size.
3df0c49c
MD
508 *
509 * Threads calling this API need to be registered RCU read-side threads.
7b783f81 510 * This function does not (necessarily) issue memory barriers.
43387742
MD
511 * cds_lfht_resize should *not* be called from a RCU read-side critical
512 * section.
f0c29ed7 513 */
b9c27904 514extern
1475579c 515void cds_lfht_resize(struct cds_lfht *ht, unsigned long new_size);
464a1ec9 516
6d320126 517/*
3a9c66db
MD
518 * Note: it is safe to perform element removal (del), replacement, or
519 * any hash table update operation during any of the following hash
520 * table traversals.
7b783f81 521 * These functions act as rcu_dereference() to read the node pointers.
6d320126
MD
522 */
523#define cds_lfht_for_each(ht, iter, node) \
524 for (cds_lfht_first(ht, iter), \
525 node = cds_lfht_iter_get_node(iter); \
526 node != NULL; \
527 cds_lfht_next(ht, iter), \
528 node = cds_lfht_iter_get_node(iter))
529
6f554439
LJ
530#define cds_lfht_for_each_duplicate(ht, hash, match, key, iter, node) \
531 for (cds_lfht_lookup(ht, hash, match, key, iter), \
6d320126
MD
532 node = cds_lfht_iter_get_node(iter); \
533 node != NULL; \
534 cds_lfht_next_duplicate(ht, match, key, iter), \
535 node = cds_lfht_iter_get_node(iter))
536
537#define cds_lfht_for_each_entry(ht, iter, pos, member) \
538 for (cds_lfht_first(ht, iter), \
539 pos = caa_container_of(cds_lfht_iter_get_node(iter), \
bdffa73a 540 __typeof__(*(pos)), member); \
92af1a30 541 cds_lfht_iter_get_node(iter) != NULL; \
6d320126
MD
542 cds_lfht_next(ht, iter), \
543 pos = caa_container_of(cds_lfht_iter_get_node(iter), \
bdffa73a 544 __typeof__(*(pos)), member))
6d320126 545
6f554439 546#define cds_lfht_for_each_entry_duplicate(ht, hash, match, key, \
6d320126 547 iter, pos, member) \
6f554439 548 for (cds_lfht_lookup(ht, hash, match, key, iter), \
6d320126 549 pos = caa_container_of(cds_lfht_iter_get_node(iter), \
bdffa73a 550 __typeof__(*(pos)), member); \
92af1a30 551 cds_lfht_iter_get_node(iter) != NULL; \
6d320126
MD
552 cds_lfht_next_duplicate(ht, match, key, iter), \
553 pos = caa_container_of(cds_lfht_iter_get_node(iter), \
bdffa73a 554 __typeof__(*(pos)), member))
6d320126 555
01389791
MD
556#ifdef __cplusplus
557}
558#endif
559
a42cc659 560#endif /* _URCU_RCULFHASH_H */
This page took 0.105425 seconds and 4 git commands to generate.