Update ABI definition files
[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
70469b43 108void cds_lfht_node_init(struct cds_lfht_node *node __attribute__((unused)))
abc490a1 109{
abc490a1 110}
674f7a69 111
4c10e9af
MD
112/*
113 * cds_lfht_node_init_deleted - initialize a hash table node to "removed" state
114 * @node: the node to initialize.
115 *
116 * Initialize the node such that cds_lfht_is_node_deleted() can be used
117 * on the node before it is added to a hash table.
118 */
119extern
120void cds_lfht_node_init_deleted(struct cds_lfht_node *node);
121
b8af5011
MD
122/*
123 * Hash table creation flags.
124 */
125enum {
126 CDS_LFHT_AUTO_RESIZE = (1U << 0),
5afadd12 127 CDS_LFHT_ACCOUNTING = (1U << 1),
b8af5011
MD
128};
129
0b6aa001
LJ
130struct cds_lfht_mm_type {
131 struct cds_lfht *(*alloc_cds_lfht)(unsigned long min_nr_alloc_buckets,
132 unsigned long max_nr_buckets);
133 void (*alloc_bucket_table)(struct cds_lfht *ht, unsigned long order);
134 void (*free_bucket_table)(struct cds_lfht *ht, unsigned long order);
135 struct cds_lfht_node *(*bucket_at)(struct cds_lfht *ht,
136 unsigned long index);
137};
138
139extern const struct cds_lfht_mm_type cds_lfht_mm_order;
308d1cb3 140extern const struct cds_lfht_mm_type cds_lfht_mm_chunk;
b0b55251 141extern const struct cds_lfht_mm_type cds_lfht_mm_mmap;
0b6aa001 142
674f7a69 143/*
7a9dcf9b 144 * _cds_lfht_new - API used by cds_lfht_new wrapper. Do not use directly.
674f7a69 145 */
b9c27904 146extern
0422d92c 147struct cds_lfht *_cds_lfht_new(unsigned long init_size,
0722081a 148 unsigned long min_nr_alloc_buckets,
747d725c 149 unsigned long max_nr_buckets,
b8af5011 150 int flags,
0b6aa001 151 const struct cds_lfht_mm_type *mm,
7b17c13e 152 const struct rcu_flavor_struct *flavor,
b7d619b0 153 pthread_attr_t *attr);
ab7d5fc6 154
938465b4
MD
155/*
156 * cds_lfht_new_flavor - allocate a hash table tied to a RCU flavor.
157 * @init_size: number of buckets to allocate initially. Must be power of two.
158 * @min_nr_alloc_buckets: the minimum number of allocated buckets.
159 * (must be power of two)
160 * @max_nr_buckets: the maximum number of hash table buckets allowed.
161 * (must be power of two, 0 is accepted, means
162 * "infinite")
163 * @flavor: flavor of liburcu to use to synchronize the hash table
164 * @flags: hash table creation flags (can be combined with bitwise or: '|').
165 * 0: no flags.
166 * CDS_LFHT_AUTO_RESIZE: automatically resize hash table.
167 * CDS_LFHT_ACCOUNTING: count the number of node addition
168 * and removal in the table
169 * @attr: optional resize worker thread attributes. NULL for default.
170 *
171 * Return NULL on error.
172 * Note: the RCU flavor must be already included before the hash table header.
173 *
174 * The programmer is responsible for ensuring that resize operation has a
175 * priority equal to hash table updater threads. It should be performed by
176 * specifying the appropriate priority in the pthread "attr" argument, and,
177 * for CDS_LFHT_AUTO_RESIZE, by ensuring that call_rcu worker threads also have
178 * this priority level. Having lower priority for call_rcu and resize threads
179 * does not pose any correctness issue, but the resize operations could be
180 * starved by updates, thus leading to long hash table bucket chains.
181 * Threads calling cds_lfht_new are NOT required to be registered RCU
182 * read-side threads. It can be called very early. (e.g. before RCU is
183 * initialized)
184 */
185static inline
186struct cds_lfht *cds_lfht_new_flavor(unsigned long init_size,
187 unsigned long min_nr_alloc_buckets,
188 unsigned long max_nr_buckets,
189 int flags,
190 const struct rcu_flavor_struct *flavor,
191 pthread_attr_t *attr)
192{
193 return _cds_lfht_new(init_size, min_nr_alloc_buckets, max_nr_buckets,
194 flags, NULL, flavor, attr);
195}
196
197
198#ifdef URCU_API_MAP
7a9dcf9b
MD
199/*
200 * cds_lfht_new - allocate a hash table.
747d725c
LJ
201 * @init_size: number of buckets to allocate initially. Must be power of two.
202 * @min_nr_alloc_buckets: the minimum number of allocated buckets.
203 * (must be power of two)
204 * @max_nr_buckets: the maximum number of hash table buckets allowed.
28d5c1b5
MD
205 * (must be power of two, 0 is accepted, means
206 * "infinite")
f22dd01d
MD
207 * @flags: hash table creation flags (can be combined with bitwise or: '|').
208 * 0: no flags.
209 * CDS_LFHT_AUTO_RESIZE: automatically resize hash table.
44bbe7fa
LJ
210 * CDS_LFHT_ACCOUNTING: count the number of node addition
211 * and removal in the table
b7d619b0 212 * @attr: optional resize worker thread attributes. NULL for default.
7a9dcf9b 213 *
7a9dcf9b
MD
214 * Return NULL on error.
215 * Note: the RCU flavor must be already included before the hash table header.
b7d619b0
MD
216 *
217 * The programmer is responsible for ensuring that resize operation has a
218 * priority equal to hash table updater threads. It should be performed by
219 * specifying the appropriate priority in the pthread "attr" argument, and,
220 * for CDS_LFHT_AUTO_RESIZE, by ensuring that call_rcu worker threads also have
221 * this priority level. Having lower priority for call_rcu and resize threads
222 * does not pose any correctness issue, but the resize operations could be
223 * starved by updates, thus leading to long hash table bucket chains.
3a9c66db
MD
224 * Threads calling cds_lfht_new are NOT required to be registered RCU
225 * read-side threads. It can be called very early. (e.g. before RCU is
226 * initialized)
7a9dcf9b
MD
227 */
228static inline
0422d92c 229struct cds_lfht *cds_lfht_new(unsigned long init_size,
0722081a 230 unsigned long min_nr_alloc_buckets,
747d725c 231 unsigned long max_nr_buckets,
b7d619b0
MD
232 int flags,
233 pthread_attr_t *attr)
7a9dcf9b 234{
7b17c13e 235 return _cds_lfht_new(init_size, min_nr_alloc_buckets, max_nr_buckets,
c1888f3a 236 flags, NULL, &rcu_flavor, attr);
7a9dcf9b 237}
938465b4 238#endif /* URCU_API_MAP */
7a9dcf9b 239
f0c29ed7 240/*
14044b37 241 * cds_lfht_destroy - destroy a hash table.
b7d619b0
MD
242 * @ht: the hash table to destroy.
243 * @attr: (output) resize worker thread attributes, as received by cds_lfht_new.
244 * The caller will typically want to free this pointer if dynamically
7f52427b
MD
245 * allocated. The attr point can be NULL if the caller does not
246 * need to be informed of the value passed to cds_lfht_new().
6878c72b
MD
247 *
248 * Return 0 on success, negative error value on error.
d0ec0ed2
MD
249
250 * Prior to liburcu 0.10:
251 * - Threads calling this API need to be registered RCU read-side
252 * threads.
253 * - cds_lfht_destroy should *not* be called from a RCU read-side
254 * critical section. It should *not* be called from a call_rcu thread
255 * context neither.
256 *
257 * Starting from liburcu 0.10, rculfhash implements its own worker
258 * thread to handle resize operations, which removes RCU requirements on
259 * cds_lfht_destroy.
f0c29ed7 260 */
b9c27904 261extern
b7d619b0 262int cds_lfht_destroy(struct cds_lfht *ht, pthread_attr_t **attr);
f0c29ed7
MD
263
264/*
14044b37 265 * cds_lfht_count_nodes - count the number of nodes in the hash table.
7f52427b 266 * @ht: the hash table.
3a9c66db
MD
267 * @split_count_before: sample the node count split-counter before traversal.
268 * @count: traverse the hash table, count the number of nodes observed.
269 * @split_count_after: sample the node count split-counter after traversal.
0422d92c 270 *
f0c29ed7 271 * Call with rcu_read_lock held.
3df0c49c 272 * Threads calling this API need to be registered RCU read-side threads.
f0c29ed7 273 */
b9c27904 274extern
14044b37 275void cds_lfht_count_nodes(struct cds_lfht *ht,
7f52427b 276 long *split_count_before,
adc0de68 277 unsigned long *count,
7f52427b 278 long *split_count_after);
ab7d5fc6 279
f0c29ed7 280/*
14044b37 281 * cds_lfht_lookup - lookup a node by key.
0422d92c 282 * @ht: the hash table.
0422d92c 283 * @hash: the key hash.
6f554439
LJ
284 * @match: the key match function.
285 * @key: the current node key.
3a9c66db 286 * @iter: node, if found (output). *iter->node set to NULL if not found.
f0c29ed7 287 *
f0c29ed7 288 * Call with rcu_read_lock held.
3df0c49c 289 * Threads calling this API need to be registered RCU read-side threads.
7b783f81 290 * This function acts as a rcu_dereference() to read the node pointer.
f0c29ed7 291 */
b9c27904 292extern
6f554439 293void cds_lfht_lookup(struct cds_lfht *ht, unsigned long hash,
996ff57c 294 cds_lfht_match_fct match, const void *key,
6f554439 295 struct cds_lfht_iter *iter);
ab7d5fc6 296
f0c29ed7 297/*
3a9c66db 298 * cds_lfht_next_duplicate - get the next item with same key, after iterator.
0422d92c
MD
299 * @ht: the hash table.
300 * @match: the key match function.
04db56f8 301 * @key: the current node key.
3a9c66db
MD
302 * @iter: input: current iterator.
303 * output: node, if found. *iter->node set to NULL if not found.
f0c29ed7 304 *
3a9c66db
MD
305 * Uses an iterator initialized by a lookup or traversal. Important: the
306 * iterator _needs_ to be initialized before calling
307 * cds_lfht_next_duplicate.
adc0de68
MD
308 * Sets *iter-node to the following node with same key.
309 * Sets *iter->node to NULL if no following node exists with same key.
310 * RCU read-side lock must be held across cds_lfht_lookup and
311 * cds_lfht_next calls, and also between cds_lfht_next calls using the
312 * node returned by a previous cds_lfht_next.
313 * Call with rcu_read_lock held.
3df0c49c 314 * Threads calling this API need to be registered RCU read-side threads.
7b783f81 315 * This function acts as a rcu_dereference() to read the node pointer.
f0c29ed7 316 */
b9c27904 317extern
0422d92c 318void cds_lfht_next_duplicate(struct cds_lfht *ht,
996ff57c 319 cds_lfht_match_fct match, const void *key,
04db56f8 320 struct cds_lfht_iter *iter);
4e9b9fbf
MD
321
322/*
323 * cds_lfht_first - get the first node in the table.
0422d92c
MD
324 * @ht: the hash table.
325 * @iter: First node, if exists (output). *iter->node set to NULL if not found.
4e9b9fbf
MD
326 *
327 * Output in "*iter". *iter->node set to NULL if table is empty.
328 * Call with rcu_read_lock held.
3df0c49c 329 * Threads calling this API need to be registered RCU read-side threads.
7b783f81 330 * This function acts as a rcu_dereference() to read the node pointer.
4e9b9fbf 331 */
b9c27904 332extern
4e9b9fbf
MD
333void cds_lfht_first(struct cds_lfht *ht, struct cds_lfht_iter *iter);
334
335/*
336 * cds_lfht_next - get the next node in the table.
0422d92c 337 * @ht: the hash table.
3a9c66db
MD
338 * @iter: input: current iterator.
339 * output: next node, if exists. *iter->node set to NULL if not found.
4e9b9fbf
MD
340 *
341 * Input/Output in "*iter". *iter->node set to NULL if *iter was
342 * pointing to the last table node.
343 * Call with rcu_read_lock held.
3df0c49c 344 * Threads calling this API need to be registered RCU read-side threads.
7b783f81 345 * This function acts as a rcu_dereference() to read the node pointer.
4e9b9fbf 346 */
b9c27904 347extern
4e9b9fbf 348void cds_lfht_next(struct cds_lfht *ht, struct cds_lfht_iter *iter);
ab7d5fc6 349
18117871 350/*
14044b37 351 * cds_lfht_add - add a node to the hash table.
0422d92c
MD
352 * @ht: the hash table.
353 * @hash: the key hash.
354 * @node: the node to add.
f0c29ed7 355 *
48ed1c18 356 * This function supports adding redundant keys into the table.
3df0c49c
MD
357 * Call with rcu_read_lock held.
358 * Threads calling this API need to be registered RCU read-side threads.
7b783f81
MD
359 * This function issues a full memory barrier before and after its
360 * atomic commit.
f0c29ed7 361 */
b9c27904 362extern
0422d92c
MD
363void cds_lfht_add(struct cds_lfht *ht, unsigned long hash,
364 struct cds_lfht_node *node);
f0c29ed7
MD
365
366/*
14044b37 367 * cds_lfht_add_unique - add a node to hash table, if key is not present.
0422d92c 368 * @ht: the hash table.
6f554439 369 * @hash: the node's hash.
0422d92c 370 * @match: the key match function.
04db56f8 371 * @key: the node's key.
0422d92c 372 * @node: the node to try adding.
f0c29ed7 373 *
6878c72b 374 * Return the node added upon success.
860d07e8
MD
375 * Return the unique node already present upon failure. If
376 * cds_lfht_add_unique fails, the node passed as parameter should be
3a9c66db 377 * freed by the caller. In this case, the caller does NOT need to wait
50024344 378 * for a grace period before freeing or re-using the node.
f0c29ed7 379 * Call with rcu_read_lock held.
3df0c49c 380 * Threads calling this API need to be registered RCU read-side threads.
48ed1c18
MD
381 *
382 * The semantic of this function is that if only this function is used
383 * to add keys into the table, no duplicated keys should ever be
384 * observable in the table. The same guarantee apply for combination of
9357c415 385 * add_unique and add_replace (see below).
7b783f81
MD
386 *
387 * Upon success, this function issues a full memory barrier before and
388 * after its atomic commit. Upon failure, this function acts like a
389 * simple lookup operation: it acts as a rcu_dereference() to read the
390 * node pointer. The failure case does not guarantee any other memory
391 * barrier.
18117871 392 */
b9c27904 393extern
adc0de68 394struct cds_lfht_node *cds_lfht_add_unique(struct cds_lfht *ht,
6f554439 395 unsigned long hash,
0422d92c 396 cds_lfht_match_fct match,
996ff57c 397 const void *key,
adc0de68 398 struct cds_lfht_node *node);
3eca1b8c 399
48ed1c18 400/*
9357c415 401 * cds_lfht_add_replace - replace or add a node within hash table.
0422d92c 402 * @ht: the hash table.
6f554439 403 * @hash: the node's hash.
0422d92c 404 * @match: the key match function.
04db56f8 405 * @key: the node's key.
0422d92c 406 * @node: the node to add.
48ed1c18
MD
407 *
408 * Return the node replaced upon success. If no node matching the key
409 * was present, return NULL, which also means the operation succeeded.
410 * This replacement operation should never fail.
411 * Call with rcu_read_lock held.
3df0c49c 412 * Threads calling this API need to be registered RCU read-side threads.
48ed1c18 413 * After successful replacement, a grace period must be waited for before
50024344 414 * freeing or re-using the memory reserved for the returned node.
48ed1c18 415 *
3a9c66db
MD
416 * The semantic of replacement vs lookups and traversals is the
417 * following: if lookups and traversals are performed between a key
418 * unique insertion and its removal, we guarantee that the lookups and
419 * traversals will always find exactly one instance of the key if it is
420 * replaced concurrently with the lookups.
48ed1c18
MD
421 *
422 * Providing this semantic allows us to ensure that replacement-only
423 * schemes will never generate duplicated keys. It also allows us to
9357c415 424 * guarantee that a combination of add_replace and add_unique updates
48ed1c18 425 * will never generate duplicated keys.
7b783f81
MD
426 *
427 * This function issues a full memory barrier before and after its
428 * atomic commit.
48ed1c18 429 */
b9c27904 430extern
9357c415 431struct cds_lfht_node *cds_lfht_add_replace(struct cds_lfht *ht,
6f554439 432 unsigned long hash,
0422d92c 433 cds_lfht_match_fct match,
996ff57c 434 const void *key,
adc0de68 435 struct cds_lfht_node *node);
48ed1c18 436
f0c29ed7 437/*
929ad508 438 * cds_lfht_replace - replace a node pointed to by iter within hash table.
0422d92c
MD
439 * @ht: the hash table.
440 * @old_iter: the iterator position of the node to replace.
2e79c445
MD
441 * @hash: the node's hash.
442 * @match: the key match function.
443 * @key: the node's key.
444 * @new_node: the new node to use as replacement.
f0c29ed7 445 *
9357c415 446 * Return 0 if replacement is successful, negative value otherwise.
2e79c445
MD
447 * Replacing a NULL old node or an already removed node will fail with
448 * -ENOENT.
449 * If the hash or value of the node to replace and the new node differ,
450 * this function returns -EINVAL without proceeding to the replacement.
9357c415
MD
451 * Old node can be looked up with cds_lfht_lookup and cds_lfht_next.
452 * RCU read-side lock must be held between lookup and replacement.
453 * Call with rcu_read_lock held.
3df0c49c 454 * Threads calling this API need to be registered RCU read-side threads.
9357c415 455 * After successful replacement, a grace period must be waited for before
50024344
MD
456 * freeing or re-using the memory reserved for the old node (which can
457 * be accessed with cds_lfht_iter_get_node).
9357c415 458 *
3a9c66db
MD
459 * The semantic of replacement vs lookups is the same as
460 * cds_lfht_add_replace().
7b783f81
MD
461 *
462 * Upon success, this function issues a full memory barrier before and
463 * after its atomic commit. Upon failure, this function does not issue
464 * any memory barrier.
9357c415 465 */
b9c27904 466extern
2e79c445
MD
467int cds_lfht_replace(struct cds_lfht *ht,
468 struct cds_lfht_iter *old_iter,
469 unsigned long hash,
470 cds_lfht_match_fct match,
471 const void *key,
9357c415
MD
472 struct cds_lfht_node *new_node);
473
474/*
475 * cds_lfht_del - remove node pointed to by iterator from hash table.
0422d92c 476 * @ht: the hash table.
bc8c3c74 477 * @node: the node to delete.
9357c415
MD
478 *
479 * Return 0 if the node is successfully removed, negative value
480 * otherwise.
bc8c3c74 481 * Deleting a NULL node or an already removed node will fail with a
9357c415 482 * negative value.
bc8c3c74
MD
483 * Node can be looked up with cds_lfht_lookup and cds_lfht_next,
484 * followed by use of cds_lfht_iter_get_node.
9357c415 485 * RCU read-side lock must be held between lookup and removal.
f0c29ed7 486 * Call with rcu_read_lock held.
3df0c49c 487 * Threads calling this API need to be registered RCU read-side threads.
48ed1c18 488 * After successful removal, a grace period must be waited for before
50024344
MD
489 * freeing or re-using the memory reserved for old node (which can be
490 * accessed with cds_lfht_iter_get_node).
7b783f81
MD
491 * Upon success, this function issues a full memory barrier before and
492 * after its atomic commit. Upon failure, this function does not issue
493 * any memory barrier.
f0c29ed7 494 */
b9c27904 495extern
bc8c3c74 496int cds_lfht_del(struct cds_lfht *ht, struct cds_lfht_node *node);
ab7d5fc6 497
df55172a 498/*
3a9c66db 499 * cds_lfht_is_node_deleted - query whether a node is removed from hash table.
df55172a
MD
500 *
501 * Return non-zero if the node is deleted from the hash table, 0
502 * otherwise.
503 * Node can be looked up with cds_lfht_lookup and cds_lfht_next,
504 * followed by use of cds_lfht_iter_get_node.
505 * RCU read-side lock must be held between lookup and call to this
506 * function.
507 * Call with rcu_read_lock held.
508 * Threads calling this API need to be registered RCU read-side threads.
7b783f81 509 * This function does not issue any memory barrier.
df55172a 510 */
b9c27904 511extern
afa5940d 512int cds_lfht_is_node_deleted(const struct cds_lfht_node *node);
df55172a 513
f0c29ed7 514/*
14044b37 515 * cds_lfht_resize - Force a hash table resize
0422d92c 516 * @ht: the hash table.
1475579c 517 * @new_size: update to this hash table size.
3df0c49c
MD
518 *
519 * Threads calling this API need to be registered RCU read-side threads.
7b783f81 520 * This function does not (necessarily) issue memory barriers.
43387742
MD
521 * cds_lfht_resize should *not* be called from a RCU read-side critical
522 * section.
f0c29ed7 523 */
b9c27904 524extern
1475579c 525void cds_lfht_resize(struct cds_lfht *ht, unsigned long new_size);
464a1ec9 526
6d320126 527/*
3a9c66db
MD
528 * Note: it is safe to perform element removal (del), replacement, or
529 * any hash table update operation during any of the following hash
530 * table traversals.
7b783f81 531 * These functions act as rcu_dereference() to read the node pointers.
6d320126
MD
532 */
533#define cds_lfht_for_each(ht, iter, node) \
534 for (cds_lfht_first(ht, iter), \
535 node = cds_lfht_iter_get_node(iter); \
536 node != NULL; \
537 cds_lfht_next(ht, iter), \
538 node = cds_lfht_iter_get_node(iter))
539
6f554439
LJ
540#define cds_lfht_for_each_duplicate(ht, hash, match, key, iter, node) \
541 for (cds_lfht_lookup(ht, hash, match, key, iter), \
6d320126
MD
542 node = cds_lfht_iter_get_node(iter); \
543 node != NULL; \
544 cds_lfht_next_duplicate(ht, match, key, iter), \
545 node = cds_lfht_iter_get_node(iter))
546
547#define cds_lfht_for_each_entry(ht, iter, pos, member) \
548 for (cds_lfht_first(ht, iter), \
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(ht, iter), \
553 pos = caa_container_of(cds_lfht_iter_get_node(iter), \
bdffa73a 554 __typeof__(*(pos)), member))
6d320126 555
6f554439 556#define cds_lfht_for_each_entry_duplicate(ht, hash, match, key, \
6d320126 557 iter, pos, member) \
6f554439 558 for (cds_lfht_lookup(ht, hash, match, key, iter), \
6d320126 559 pos = caa_container_of(cds_lfht_iter_get_node(iter), \
bdffa73a 560 __typeof__(*(pos)), member); \
92af1a30 561 cds_lfht_iter_get_node(iter) != NULL; \
6d320126
MD
562 cds_lfht_next_duplicate(ht, match, key, iter), \
563 pos = caa_container_of(cds_lfht_iter_get_node(iter), \
bdffa73a 564 __typeof__(*(pos)), member))
6d320126 565
01389791
MD
566#ifdef __cplusplus
567}
568#endif
569
a42cc659 570#endif /* _URCU_RCULFHASH_H */
This page took 0.12563 seconds and 4 git commands to generate.