Phase 1 of deprecating liburcu-signal
[urcu.git] / include / urcu / rculfhash.h
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1// SPDX-FileCopyrightText: 2011 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
2// SPDX-FileCopyrightText: 2011 Lai Jiangshan <laijs@cn.fujitsu.com>
3//
4// SPDX-License-Identifier: LGPL-2.1-or-later
5
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6#ifndef _URCU_RCULFHASH_H
7#define _URCU_RCULFHASH_H
ab7d5fc6 8
f0c29ed7 9/*
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10 * Userspace RCU library - Lock-Free RCU Hash Table
11 *
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12 * For use with URCU_API_MAP (API mapping of liburcu), include this file
13 * _after_ including your URCU flavor.
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14 */
15
d7c76f85 16#include <urcu/config.h>
674f7a69 17#include <stdint.h>
6bcce235 18#include <pthread.h>
6d320126 19#include <urcu/compiler.h>
abc490a1 20
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21#ifdef __cplusplus
22extern "C" {
23#endif
24
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25struct cds_lfht;
26
7f52427b 27/*
04db56f8 28 * cds_lfht_node: Contains the next pointers and reverse-hash
7f52427b 29 * value required for lookup and traversal of the hash table.
04db56f8 30 *
db00ccc3 31 * struct cds_lfht_node should be aligned on 8-bytes boundaries because
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32 * the three lower bits are used as flags. It is worth noting that the
33 * information contained within these three bits could be represented on
34 * two bits by re-using the same bit for REMOVAL_OWNER_FLAG and
35 * BUCKET_FLAG. This can be done if we ensure that no iterator nor
36 * updater check the BUCKET_FLAG after it detects that the REMOVED_FLAG
37 * is set. Given the minimum size of struct cds_lfht_node is 8 bytes on
38 * 32-bit architectures, we choose to go for simplicity and reserve
39 * three bits.
7f52427b 40 *
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41 * struct cds_lfht_node can be embedded into a structure (as a field).
42 * caa_container_of() can be used to get the structure from the struct
43 * cds_lfht_node after a lookup.
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44 *
45 * The structure which embeds it typically holds the key (or key-value
46 * pair) of the object. The caller code is responsible for calculation
47 * of the hash value for cds_lfht APIs.
ae62aa6a 48 */
14044b37 49struct cds_lfht_node {
3f2f3714 50 struct cds_lfht_node *next; /* ptr | REMOVAL_OWNER_FLAG | BUCKET_FLAG | REMOVED_FLAG */
04db56f8 51 unsigned long reverse_hash;
db00ccc3 52} __attribute__((aligned(8)));
abc490a1 53
7f52427b 54/* cds_lfht_iter: Used to track state while traversing a hash chain. */
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55struct cds_lfht_iter {
56 struct cds_lfht_node *node, *next;
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57 /*
58 * For debugging purposes, build both API users and rculfhash
59 * library with CDS_LFHT_ITER_DEBUG defined. This enables extra
60 * consistency checks for calls to a cds_lfht_next() or
61 * cds_lfht_next_duplicate() after the iterator has been
62 * re-purposed to iterate on a different hash table. This is a
63 * common programming mistake when performing hash table lookup
64 * nested in a hash table traversal.
65 */
66#ifdef CONFIG_CDS_LFHT_ITER_DEBUG
67 struct cds_lfht *lfht;
68#endif
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69};
70
71static inline
72struct cds_lfht_node *cds_lfht_iter_get_node(struct cds_lfht_iter *iter)
73{
74 return iter->node;
75}
76
938465b4 77struct rcu_flavor_struct;
ab7d5fc6 78
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79/*
80 * Caution !
abc490a1 81 * Ensure reader and writer threads are registered as urcu readers.
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82 */
83
996ff57c 84typedef int (*cds_lfht_match_fct)(struct cds_lfht_node *node, const void *key);
abc490a1 85
f0c29ed7 86/*
14044b37 87 * cds_lfht_node_init - initialize a hash table node
0422d92c 88 * @node: the node to initialize.
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89 *
90 * This function is kept to be eventually used for debugging purposes
91 * (detection of memory corruption).
f0c29ed7 92 */
abc490a1 93static inline
70469b43 94void cds_lfht_node_init(struct cds_lfht_node *node __attribute__((unused)))
abc490a1 95{
abc490a1 96}
674f7a69 97
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98/*
99 * cds_lfht_node_init_deleted - initialize a hash table node to "removed" state
100 * @node: the node to initialize.
101 *
102 * Initialize the node such that cds_lfht_is_node_deleted() can be used
103 * on the node before it is added to a hash table.
104 */
105extern
106void cds_lfht_node_init_deleted(struct cds_lfht_node *node);
107
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108/*
109 * Hash table creation flags.
110 */
111enum {
112 CDS_LFHT_AUTO_RESIZE = (1U << 0),
5afadd12 113 CDS_LFHT_ACCOUNTING = (1U << 1),
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114};
115
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116struct cds_lfht_mm_type {
117 struct cds_lfht *(*alloc_cds_lfht)(unsigned long min_nr_alloc_buckets,
118 unsigned long max_nr_buckets);
119 void (*alloc_bucket_table)(struct cds_lfht *ht, unsigned long order);
120 void (*free_bucket_table)(struct cds_lfht *ht, unsigned long order);
121 struct cds_lfht_node *(*bucket_at)(struct cds_lfht *ht,
122 unsigned long index);
123};
124
125extern const struct cds_lfht_mm_type cds_lfht_mm_order;
308d1cb3 126extern const struct cds_lfht_mm_type cds_lfht_mm_chunk;
b0b55251 127extern const struct cds_lfht_mm_type cds_lfht_mm_mmap;
0b6aa001 128
674f7a69 129/*
7a9dcf9b 130 * _cds_lfht_new - API used by cds_lfht_new wrapper. Do not use directly.
674f7a69 131 */
b9c27904 132extern
0422d92c 133struct cds_lfht *_cds_lfht_new(unsigned long init_size,
0722081a 134 unsigned long min_nr_alloc_buckets,
747d725c 135 unsigned long max_nr_buckets,
b8af5011 136 int flags,
0b6aa001 137 const struct cds_lfht_mm_type *mm,
7b17c13e 138 const struct rcu_flavor_struct *flavor,
b7d619b0 139 pthread_attr_t *attr);
ab7d5fc6 140
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141/*
142 * cds_lfht_new_flavor - allocate a hash table tied to a RCU flavor.
143 * @init_size: number of buckets to allocate initially. Must be power of two.
144 * @min_nr_alloc_buckets: the minimum number of allocated buckets.
145 * (must be power of two)
146 * @max_nr_buckets: the maximum number of hash table buckets allowed.
147 * (must be power of two, 0 is accepted, means
148 * "infinite")
149 * @flavor: flavor of liburcu to use to synchronize the hash table
150 * @flags: hash table creation flags (can be combined with bitwise or: '|').
151 * 0: no flags.
152 * CDS_LFHT_AUTO_RESIZE: automatically resize hash table.
153 * CDS_LFHT_ACCOUNTING: count the number of node addition
154 * and removal in the table
155 * @attr: optional resize worker thread attributes. NULL for default.
156 *
157 * Return NULL on error.
158 * Note: the RCU flavor must be already included before the hash table header.
159 *
160 * The programmer is responsible for ensuring that resize operation has a
161 * priority equal to hash table updater threads. It should be performed by
162 * specifying the appropriate priority in the pthread "attr" argument, and,
163 * for CDS_LFHT_AUTO_RESIZE, by ensuring that call_rcu worker threads also have
164 * this priority level. Having lower priority for call_rcu and resize threads
165 * does not pose any correctness issue, but the resize operations could be
166 * starved by updates, thus leading to long hash table bucket chains.
167 * Threads calling cds_lfht_new are NOT required to be registered RCU
168 * read-side threads. It can be called very early. (e.g. before RCU is
169 * initialized)
170 */
171static inline
172struct cds_lfht *cds_lfht_new_flavor(unsigned long init_size,
173 unsigned long min_nr_alloc_buckets,
174 unsigned long max_nr_buckets,
175 int flags,
176 const struct rcu_flavor_struct *flavor,
177 pthread_attr_t *attr)
178{
179 return _cds_lfht_new(init_size, min_nr_alloc_buckets, max_nr_buckets,
180 flags, NULL, flavor, attr);
181}
182
183
184#ifdef URCU_API_MAP
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185/*
186 * cds_lfht_new - allocate a hash table.
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187 * @init_size: number of buckets to allocate initially. Must be power of two.
188 * @min_nr_alloc_buckets: the minimum number of allocated buckets.
189 * (must be power of two)
190 * @max_nr_buckets: the maximum number of hash table buckets allowed.
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191 * (must be power of two, 0 is accepted, means
192 * "infinite")
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193 * @flags: hash table creation flags (can be combined with bitwise or: '|').
194 * 0: no flags.
195 * CDS_LFHT_AUTO_RESIZE: automatically resize hash table.
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196 * CDS_LFHT_ACCOUNTING: count the number of node addition
197 * and removal in the table
b7d619b0 198 * @attr: optional resize worker thread attributes. NULL for default.
7a9dcf9b 199 *
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200 * Return NULL on error.
201 * Note: the RCU flavor must be already included before the hash table header.
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202 *
203 * The programmer is responsible for ensuring that resize operation has a
204 * priority equal to hash table updater threads. It should be performed by
205 * specifying the appropriate priority in the pthread "attr" argument, and,
206 * for CDS_LFHT_AUTO_RESIZE, by ensuring that call_rcu worker threads also have
207 * this priority level. Having lower priority for call_rcu and resize threads
208 * does not pose any correctness issue, but the resize operations could be
209 * starved by updates, thus leading to long hash table bucket chains.
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210 * Threads calling cds_lfht_new are NOT required to be registered RCU
211 * read-side threads. It can be called very early. (e.g. before RCU is
212 * initialized)
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213 */
214static inline
0422d92c 215struct cds_lfht *cds_lfht_new(unsigned long init_size,
0722081a 216 unsigned long min_nr_alloc_buckets,
747d725c 217 unsigned long max_nr_buckets,
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218 int flags,
219 pthread_attr_t *attr)
7a9dcf9b 220{
7b17c13e 221 return _cds_lfht_new(init_size, min_nr_alloc_buckets, max_nr_buckets,
c1888f3a 222 flags, NULL, &rcu_flavor, attr);
7a9dcf9b 223}
938465b4 224#endif /* URCU_API_MAP */
7a9dcf9b 225
f0c29ed7 226/*
14044b37 227 * cds_lfht_destroy - destroy a hash table.
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228 * @ht: the hash table to destroy.
229 * @attr: (output) resize worker thread attributes, as received by cds_lfht_new.
230 * The caller will typically want to free this pointer if dynamically
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231 * allocated. The attr point can be NULL if the caller does not
232 * need to be informed of the value passed to cds_lfht_new().
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233 *
234 * Return 0 on success, negative error value on error.
d0ec0ed2 235
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236 * Threads calling this API need to be registered RCU read-side threads.
237 *
d0ec0ed2 238 * Prior to liburcu 0.10:
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239 * - cds_lfht_destroy should *not* be called from a RCU read-side
240 * critical section. It should *not* be called from a call_rcu thread
241 * context neither.
242 *
243 * Starting from liburcu 0.10, rculfhash implements its own worker
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244 * thread to handle resize operations, which removes the above RCU
245 * read-side critical section requirement on cds_lfht_destroy.
f0c29ed7 246 */
b9c27904 247extern
b7d619b0 248int cds_lfht_destroy(struct cds_lfht *ht, pthread_attr_t **attr);
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249
250/*
14044b37 251 * cds_lfht_count_nodes - count the number of nodes in the hash table.
7f52427b 252 * @ht: the hash table.
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253 * @split_count_before: sample the node count split-counter before traversal.
254 * @count: traverse the hash table, count the number of nodes observed.
255 * @split_count_after: sample the node count split-counter after traversal.
0422d92c 256 *
f0c29ed7 257 * Call with rcu_read_lock held.
3df0c49c 258 * Threads calling this API need to be registered RCU read-side threads.
f0c29ed7 259 */
b9c27904 260extern
14044b37 261void cds_lfht_count_nodes(struct cds_lfht *ht,
7f52427b 262 long *split_count_before,
adc0de68 263 unsigned long *count,
7f52427b 264 long *split_count_after);
ab7d5fc6 265
f0c29ed7 266/*
14044b37 267 * cds_lfht_lookup - lookup a node by key.
0422d92c 268 * @ht: the hash table.
0422d92c 269 * @hash: the key hash.
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270 * @match: the key match function.
271 * @key: the current node key.
3a9c66db 272 * @iter: node, if found (output). *iter->node set to NULL if not found.
f0c29ed7 273 *
f0c29ed7 274 * Call with rcu_read_lock held.
3df0c49c 275 * Threads calling this API need to be registered RCU read-side threads.
7b783f81 276 * This function acts as a rcu_dereference() to read the node pointer.
f0c29ed7 277 */
b9c27904 278extern
6f554439 279void cds_lfht_lookup(struct cds_lfht *ht, unsigned long hash,
996ff57c 280 cds_lfht_match_fct match, const void *key,
6f554439 281 struct cds_lfht_iter *iter);
ab7d5fc6 282
f0c29ed7 283/*
3a9c66db 284 * cds_lfht_next_duplicate - get the next item with same key, after iterator.
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285 * @ht: the hash table.
286 * @match: the key match function.
04db56f8 287 * @key: the current node key.
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288 * @iter: input: current iterator.
289 * output: node, if found. *iter->node set to NULL if not found.
f0c29ed7 290 *
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291 * Uses an iterator initialized by a lookup or traversal. Important: the
292 * iterator _needs_ to be initialized before calling
293 * cds_lfht_next_duplicate.
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294 * Sets *iter-node to the following node with same key.
295 * Sets *iter->node to NULL if no following node exists with same key.
296 * RCU read-side lock must be held across cds_lfht_lookup and
297 * cds_lfht_next calls, and also between cds_lfht_next calls using the
298 * node returned by a previous cds_lfht_next.
299 * Call with rcu_read_lock held.
3df0c49c 300 * Threads calling this API need to be registered RCU read-side threads.
7b783f81 301 * This function acts as a rcu_dereference() to read the node pointer.
f0c29ed7 302 */
b9c27904 303extern
0422d92c 304void cds_lfht_next_duplicate(struct cds_lfht *ht,
996ff57c 305 cds_lfht_match_fct match, const void *key,
04db56f8 306 struct cds_lfht_iter *iter);
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307
308/*
309 * cds_lfht_first - get the first node in the table.
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310 * @ht: the hash table.
311 * @iter: First node, if exists (output). *iter->node set to NULL if not found.
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312 *
313 * Output in "*iter". *iter->node set to NULL if table is empty.
314 * Call with rcu_read_lock held.
3df0c49c 315 * Threads calling this API need to be registered RCU read-side threads.
7b783f81 316 * This function acts as a rcu_dereference() to read the node pointer.
4e9b9fbf 317 */
b9c27904 318extern
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319void cds_lfht_first(struct cds_lfht *ht, struct cds_lfht_iter *iter);
320
321/*
322 * cds_lfht_next - get the next node in the table.
0422d92c 323 * @ht: the hash table.
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324 * @iter: input: current iterator.
325 * output: next node, if exists. *iter->node set to NULL if not found.
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326 *
327 * Input/Output in "*iter". *iter->node set to NULL if *iter was
328 * pointing to the last table node.
329 * Call with rcu_read_lock held.
3df0c49c 330 * Threads calling this API need to be registered RCU read-side threads.
7b783f81 331 * This function acts as a rcu_dereference() to read the node pointer.
4e9b9fbf 332 */
b9c27904 333extern
4e9b9fbf 334void cds_lfht_next(struct cds_lfht *ht, struct cds_lfht_iter *iter);
ab7d5fc6 335
18117871 336/*
14044b37 337 * cds_lfht_add - add a node to the hash table.
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338 * @ht: the hash table.
339 * @hash: the key hash.
340 * @node: the node to add.
f0c29ed7 341 *
48ed1c18 342 * This function supports adding redundant keys into the table.
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343 * Call with rcu_read_lock held.
344 * Threads calling this API need to be registered RCU read-side threads.
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345 * This function issues a full memory barrier before and after its
346 * atomic commit.
f0c29ed7 347 */
b9c27904 348extern
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349void cds_lfht_add(struct cds_lfht *ht, unsigned long hash,
350 struct cds_lfht_node *node);
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351
352/*
14044b37 353 * cds_lfht_add_unique - add a node to hash table, if key is not present.
0422d92c 354 * @ht: the hash table.
6f554439 355 * @hash: the node's hash.
0422d92c 356 * @match: the key match function.
04db56f8 357 * @key: the node's key.
0422d92c 358 * @node: the node to try adding.
f0c29ed7 359 *
6878c72b 360 * Return the node added upon success.
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361 * Return the unique node already present upon failure. If
362 * cds_lfht_add_unique fails, the node passed as parameter should be
3a9c66db 363 * freed by the caller. In this case, the caller does NOT need to wait
50024344 364 * for a grace period before freeing or re-using the node.
f0c29ed7 365 * Call with rcu_read_lock held.
3df0c49c 366 * Threads calling this API need to be registered RCU read-side threads.
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367 *
368 * The semantic of this function is that if only this function is used
369 * to add keys into the table, no duplicated keys should ever be
370 * observable in the table. The same guarantee apply for combination of
9357c415 371 * add_unique and add_replace (see below).
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372 *
373 * Upon success, this function issues a full memory barrier before and
374 * after its atomic commit. Upon failure, this function acts like a
375 * simple lookup operation: it acts as a rcu_dereference() to read the
376 * node pointer. The failure case does not guarantee any other memory
377 * barrier.
18117871 378 */
b9c27904 379extern
adc0de68 380struct cds_lfht_node *cds_lfht_add_unique(struct cds_lfht *ht,
6f554439 381 unsigned long hash,
0422d92c 382 cds_lfht_match_fct match,
996ff57c 383 const void *key,
adc0de68 384 struct cds_lfht_node *node);
3eca1b8c 385
48ed1c18 386/*
9357c415 387 * cds_lfht_add_replace - replace or add a node within hash table.
0422d92c 388 * @ht: the hash table.
6f554439 389 * @hash: the node's hash.
0422d92c 390 * @match: the key match function.
04db56f8 391 * @key: the node's key.
0422d92c 392 * @node: the node to add.
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393 *
394 * Return the node replaced upon success. If no node matching the key
395 * was present, return NULL, which also means the operation succeeded.
396 * This replacement operation should never fail.
397 * Call with rcu_read_lock held.
3df0c49c 398 * Threads calling this API need to be registered RCU read-side threads.
48ed1c18 399 * After successful replacement, a grace period must be waited for before
50024344 400 * freeing or re-using the memory reserved for the returned node.
48ed1c18 401 *
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402 * The semantic of replacement vs lookups and traversals is the
403 * following: if lookups and traversals are performed between a key
404 * unique insertion and its removal, we guarantee that the lookups and
405 * traversals will always find exactly one instance of the key if it is
406 * replaced concurrently with the lookups.
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407 *
408 * Providing this semantic allows us to ensure that replacement-only
409 * schemes will never generate duplicated keys. It also allows us to
9357c415 410 * guarantee that a combination of add_replace and add_unique updates
48ed1c18 411 * will never generate duplicated keys.
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412 *
413 * This function issues a full memory barrier before and after its
414 * atomic commit.
48ed1c18 415 */
b9c27904 416extern
9357c415 417struct cds_lfht_node *cds_lfht_add_replace(struct cds_lfht *ht,
6f554439 418 unsigned long hash,
0422d92c 419 cds_lfht_match_fct match,
996ff57c 420 const void *key,
adc0de68 421 struct cds_lfht_node *node);
48ed1c18 422
f0c29ed7 423/*
929ad508 424 * cds_lfht_replace - replace a node pointed to by iter within hash table.
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425 * @ht: the hash table.
426 * @old_iter: the iterator position of the node to replace.
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427 * @hash: the node's hash.
428 * @match: the key match function.
429 * @key: the node's key.
430 * @new_node: the new node to use as replacement.
f0c29ed7 431 *
9357c415 432 * Return 0 if replacement is successful, negative value otherwise.
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433 * Replacing a NULL old node or an already removed node will fail with
434 * -ENOENT.
435 * If the hash or value of the node to replace and the new node differ,
436 * this function returns -EINVAL without proceeding to the replacement.
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437 * Old node can be looked up with cds_lfht_lookup and cds_lfht_next.
438 * RCU read-side lock must be held between lookup and replacement.
439 * Call with rcu_read_lock held.
3df0c49c 440 * Threads calling this API need to be registered RCU read-side threads.
9357c415 441 * After successful replacement, a grace period must be waited for before
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442 * freeing or re-using the memory reserved for the old node (which can
443 * be accessed with cds_lfht_iter_get_node).
9357c415 444 *
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445 * The semantic of replacement vs lookups is the same as
446 * cds_lfht_add_replace().
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447 *
448 * Upon success, this function issues a full memory barrier before and
449 * after its atomic commit. Upon failure, this function does not issue
450 * any memory barrier.
9357c415 451 */
b9c27904 452extern
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453int cds_lfht_replace(struct cds_lfht *ht,
454 struct cds_lfht_iter *old_iter,
455 unsigned long hash,
456 cds_lfht_match_fct match,
457 const void *key,
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458 struct cds_lfht_node *new_node);
459
460/*
461 * cds_lfht_del - remove node pointed to by iterator from hash table.
0422d92c 462 * @ht: the hash table.
bc8c3c74 463 * @node: the node to delete.
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464 *
465 * Return 0 if the node is successfully removed, negative value
466 * otherwise.
bc8c3c74 467 * Deleting a NULL node or an already removed node will fail with a
9357c415 468 * negative value.
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469 * Node can be looked up with cds_lfht_lookup and cds_lfht_next,
470 * followed by use of cds_lfht_iter_get_node.
9357c415 471 * RCU read-side lock must be held between lookup and removal.
f0c29ed7 472 * Call with rcu_read_lock held.
3df0c49c 473 * Threads calling this API need to be registered RCU read-side threads.
48ed1c18 474 * After successful removal, a grace period must be waited for before
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475 * freeing or re-using the memory reserved for old node (which can be
476 * accessed with cds_lfht_iter_get_node).
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477 * Upon success, this function issues a full memory barrier before and
478 * after its atomic commit. Upon failure, this function does not issue
479 * any memory barrier.
f0c29ed7 480 */
b9c27904 481extern
bc8c3c74 482int cds_lfht_del(struct cds_lfht *ht, struct cds_lfht_node *node);
ab7d5fc6 483
df55172a 484/*
3a9c66db 485 * cds_lfht_is_node_deleted - query whether a node is removed from hash table.
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486 *
487 * Return non-zero if the node is deleted from the hash table, 0
488 * otherwise.
489 * Node can be looked up with cds_lfht_lookup and cds_lfht_next,
490 * followed by use of cds_lfht_iter_get_node.
491 * RCU read-side lock must be held between lookup and call to this
492 * function.
493 * Call with rcu_read_lock held.
494 * Threads calling this API need to be registered RCU read-side threads.
7b783f81 495 * This function does not issue any memory barrier.
df55172a 496 */
b9c27904 497extern
afa5940d 498int cds_lfht_is_node_deleted(const struct cds_lfht_node *node);
df55172a 499
f0c29ed7 500/*
14044b37 501 * cds_lfht_resize - Force a hash table resize
0422d92c 502 * @ht: the hash table.
1475579c 503 * @new_size: update to this hash table size.
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504 *
505 * Threads calling this API need to be registered RCU read-side threads.
7b783f81 506 * This function does not (necessarily) issue memory barriers.
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507 * cds_lfht_resize should *not* be called from a RCU read-side critical
508 * section.
f0c29ed7 509 */
b9c27904 510extern
1475579c 511void cds_lfht_resize(struct cds_lfht *ht, unsigned long new_size);
464a1ec9 512
6d320126 513/*
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514 * Note: it is safe to perform element removal (del), replacement, or
515 * any hash table update operation during any of the following hash
516 * table traversals.
7b783f81 517 * These functions act as rcu_dereference() to read the node pointers.
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518 */
519#define cds_lfht_for_each(ht, iter, node) \
520 for (cds_lfht_first(ht, iter), \
521 node = cds_lfht_iter_get_node(iter); \
522 node != NULL; \
523 cds_lfht_next(ht, iter), \
524 node = cds_lfht_iter_get_node(iter))
525
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526#define cds_lfht_for_each_duplicate(ht, hash, match, key, iter, node) \
527 for (cds_lfht_lookup(ht, hash, match, key, iter), \
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528 node = cds_lfht_iter_get_node(iter); \
529 node != NULL; \
530 cds_lfht_next_duplicate(ht, match, key, iter), \
531 node = cds_lfht_iter_get_node(iter))
532
e58cdfcf 533#define cds_lfht_entry(ptr, type, member) \
0ef4782c 534 caa_container_of_check_null(ptr, type, member)
e58cdfcf 535
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536#define cds_lfht_for_each_entry(ht, iter, pos, member) \
537 for (cds_lfht_first(ht, iter), \
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538 pos = cds_lfht_entry(cds_lfht_iter_get_node(iter), \
539 __typeof__(*(pos)), member); \
540 pos != NULL; \
6d320126 541 cds_lfht_next(ht, iter), \
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542 pos = cds_lfht_entry(cds_lfht_iter_get_node(iter), \
543 __typeof__(*(pos)), member))
6d320126 544
6f554439 545#define cds_lfht_for_each_entry_duplicate(ht, hash, match, key, \
6d320126 546 iter, pos, member) \
6f554439 547 for (cds_lfht_lookup(ht, hash, match, key, iter), \
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548 pos = cds_lfht_entry(cds_lfht_iter_get_node(iter), \
549 __typeof__(*(pos)), member); \
550 pos != NULL; \
6d320126 551 cds_lfht_next_duplicate(ht, match, key, iter), \
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552 pos = cds_lfht_entry(cds_lfht_iter_get_node(iter), \
553 __typeof__(*(pos)), member))
6d320126 554
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555#ifdef __cplusplus
556}
557#endif
558
a42cc659 559#endif /* _URCU_RCULFHASH_H */
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