1#ifndef _LINUX_RCULIST_H 2#define _LINUX_RCULIST_H 3 4#ifdef __KERNEL__ 5 6/* 7 * RCU-protected list version 8 */ 9#include <linux/list.h> 10#include <linux/rcupdate.h> 11 12/* 13 * Why is there no list_empty_rcu()? Because list_empty() serves this 14 * purpose. The list_empty() function fetches the RCU-protected pointer 15 * and compares it to the address of the list head, but neither dereferences 16 * this pointer itself nor provides this pointer to the caller. Therefore, 17 * it is not necessary to use rcu_dereference(), so that list_empty() can 18 * be used anywhere you would want to use a list_empty_rcu(). 19 */ 20 21/* 22 * INIT_LIST_HEAD_RCU - Initialize a list_head visible to RCU readers 23 * @list: list to be initialized 24 * 25 * You should instead use INIT_LIST_HEAD() for normal initialization and 26 * cleanup tasks, when readers have no access to the list being initialized. 27 * However, if the list being initialized is visible to readers, you 28 * need to keep the compiler from being too mischievous. 29 */ 30static inline void INIT_LIST_HEAD_RCU(struct list_head *list) 31{ 32 WRITE_ONCE(list->next, list); 33 WRITE_ONCE(list->prev, list); 34} 35 36/* 37 * return the ->next pointer of a list_head in an rcu safe 38 * way, we must not access it directly 39 */ 40#define list_next_rcu(list) (*((struct list_head __rcu **)(&(list)->next))) 41 42/* 43 * Insert a new entry between two known consecutive entries. 44 * 45 * This is only for internal list manipulation where we know 46 * the prev/next entries already! 47 */ 48static inline void __list_add_rcu(struct list_head *new, 49 struct list_head *prev, struct list_head *next) 50{ 51 if (!__list_add_valid(new, prev, next)) 52 return; 53 54 new->next = next; 55 new->prev = prev; 56 rcu_assign_pointer(list_next_rcu(prev), new); 57 next->prev = new; 58} 59 60/** 61 * list_add_rcu - add a new entry to rcu-protected list 62 * @new: new entry to be added 63 * @head: list head to add it after 64 * 65 * Insert a new entry after the specified head. 66 * This is good for implementing stacks. 67 * 68 * The caller must take whatever precautions are necessary 69 * (such as holding appropriate locks) to avoid racing 70 * with another list-mutation primitive, such as list_add_rcu() 71 * or list_del_rcu(), running on this same list. 72 * However, it is perfectly legal to run concurrently with 73 * the _rcu list-traversal primitives, such as 74 * list_for_each_entry_rcu(). 75 */ 76static inline void list_add_rcu(struct list_head *new, struct list_head *head) 77{ 78 __list_add_rcu(new, head, head->next); 79} 80 81/** 82 * list_add_tail_rcu - add a new entry to rcu-protected list 83 * @new: new entry to be added 84 * @head: list head to add it before 85 * 86 * Insert a new entry before the specified head. 87 * This is useful for implementing queues. 88 * 89 * The caller must take whatever precautions are necessary 90 * (such as holding appropriate locks) to avoid racing 91 * with another list-mutation primitive, such as list_add_tail_rcu() 92 * or list_del_rcu(), running on this same list. 93 * However, it is perfectly legal to run concurrently with 94 * the _rcu list-traversal primitives, such as 95 * list_for_each_entry_rcu(). 96 */ 97static inline void list_add_tail_rcu(struct list_head *new, 98 struct list_head *head) 99{ 100 __list_add_rcu(new, head->prev, head); 101} 102 103/** 104 * list_del_rcu - deletes entry from list without re-initialization 105 * @entry: the element to delete from the list. 106 * 107 * Note: list_empty() on entry does not return true after this, 108 * the entry is in an undefined state. It is useful for RCU based 109 * lockfree traversal. 110 * 111 * In particular, it means that we can not poison the forward 112 * pointers that may still be used for walking the list. 113 * 114 * The caller must take whatever precautions are necessary 115 * (such as holding appropriate locks) to avoid racing 116 * with another list-mutation primitive, such as list_del_rcu() 117 * or list_add_rcu(), running on this same list. 118 * However, it is perfectly legal to run concurrently with 119 * the _rcu list-traversal primitives, such as 120 * list_for_each_entry_rcu(). 121 * 122 * Note that the caller is not permitted to immediately free 123 * the newly deleted entry. Instead, either synchronize_rcu() 124 * or call_rcu() must be used to defer freeing until an RCU 125 * grace period has elapsed. 126 */ 127static inline void list_del_rcu(struct list_head *entry) 128{ 129 __list_del_entry(entry); 130 entry->prev = LIST_POISON2; 131} 132 133/** 134 * hlist_del_init_rcu - deletes entry from hash list with re-initialization 135 * @n: the element to delete from the hash list. 136 * 137 * Note: list_unhashed() on the node return true after this. It is 138 * useful for RCU based read lockfree traversal if the writer side 139 * must know if the list entry is still hashed or already unhashed. 140 * 141 * In particular, it means that we can not poison the forward pointers 142 * that may still be used for walking the hash list and we can only 143 * zero the pprev pointer so list_unhashed() will return true after 144 * this. 145 * 146 * The caller must take whatever precautions are necessary (such as 147 * holding appropriate locks) to avoid racing with another 148 * list-mutation primitive, such as hlist_add_head_rcu() or 149 * hlist_del_rcu(), running on this same list. However, it is 150 * perfectly legal to run concurrently with the _rcu list-traversal 151 * primitives, such as hlist_for_each_entry_rcu(). 152 */ 153static inline void hlist_del_init_rcu(struct hlist_node *n) 154{ 155 if (!hlist_unhashed(n)) { 156 __hlist_del(n); 157 n->pprev = NULL; 158 } 159} 160 161/** 162 * list_replace_rcu - replace old entry by new one 163 * @old : the element to be replaced 164 * @new : the new element to insert 165 * 166 * The @old entry will be replaced with the @new entry atomically. 167 * Note: @old should not be empty. 168 */ 169static inline void list_replace_rcu(struct list_head *old, 170 struct list_head *new) 171{ 172 new->next = old->next; 173 new->prev = old->prev; 174 rcu_assign_pointer(list_next_rcu(new->prev), new); 175 new->next->prev = new; 176 old->prev = LIST_POISON2; 177} 178 179/** 180 * __list_splice_init_rcu - join an RCU-protected list into an existing list. 181 * @list: the RCU-protected list to splice 182 * @prev: points to the last element of the existing list 183 * @next: points to the first element of the existing list 184 * @sync: function to sync: synchronize_rcu(), synchronize_sched(), ... 185 * 186 * The list pointed to by @prev and @next can be RCU-read traversed 187 * concurrently with this function. 188 * 189 * Note that this function blocks. 190 * 191 * Important note: the caller must take whatever action is necessary to prevent 192 * any other updates to the existing list. In principle, it is possible to 193 * modify the list as soon as sync() begins execution. If this sort of thing 194 * becomes necessary, an alternative version based on call_rcu() could be 195 * created. But only if -really- needed -- there is no shortage of RCU API 196 * members. 197 */ 198static inline void __list_splice_init_rcu(struct list_head *list, 199 struct list_head *prev, 200 struct list_head *next, 201 void (*sync)(void)) 202{ 203 struct list_head *first = list->next; 204 struct list_head *last = list->prev; 205 206 /* 207 * "first" and "last" tracking list, so initialize it. RCU readers 208 * have access to this list, so we must use INIT_LIST_HEAD_RCU() 209 * instead of INIT_LIST_HEAD(). 210 */ 211 212 INIT_LIST_HEAD_RCU(list); 213 214 /* 215 * At this point, the list body still points to the source list. 216 * Wait for any readers to finish using the list before splicing 217 * the list body into the new list. Any new readers will see 218 * an empty list. 219 */ 220 221 sync(); 222 223 /* 224 * Readers are finished with the source list, so perform splice. 225 * The order is important if the new list is global and accessible 226 * to concurrent RCU readers. Note that RCU readers are not 227 * permitted to traverse the prev pointers without excluding 228 * this function. 229 */ 230 231 last->next = next; 232 rcu_assign_pointer(list_next_rcu(prev), first); 233 first->prev = prev; 234 next->prev = last; 235} 236 237/** 238 * list_splice_init_rcu - splice an RCU-protected list into an existing list, 239 * designed for stacks. 240 * @list: the RCU-protected list to splice 241 * @head: the place in the existing list to splice the first list into 242 * @sync: function to sync: synchronize_rcu(), synchronize_sched(), ... 243 */ 244static inline void list_splice_init_rcu(struct list_head *list, 245 struct list_head *head, 246 void (*sync)(void)) 247{ 248 if (!list_empty(list)) 249 __list_splice_init_rcu(list, head, head->next, sync); 250} 251 252/** 253 * list_splice_tail_init_rcu - splice an RCU-protected list into an existing 254 * list, designed for queues. 255 * @list: the RCU-protected list to splice 256 * @head: the place in the existing list to splice the first list into 257 * @sync: function to sync: synchronize_rcu(), synchronize_sched(), ... 258 */ 259static inline void list_splice_tail_init_rcu(struct list_head *list, 260 struct list_head *head, 261 void (*sync)(void)) 262{ 263 if (!list_empty(list)) 264 __list_splice_init_rcu(list, head->prev, head, sync); 265} 266 267/** 268 * list_entry_rcu - get the struct for this entry 269 * @ptr: the &struct list_head pointer. 270 * @type: the type of the struct this is embedded in. 271 * @member: the name of the list_head within the struct. 272 * 273 * This primitive may safely run concurrently with the _rcu list-mutation 274 * primitives such as list_add_rcu() as long as it's guarded by rcu_read_lock(). 275 */ 276#define list_entry_rcu(ptr, type, member) \ 277 container_of(lockless_dereference(ptr), type, member) 278 279/** 280 * Where are list_empty_rcu() and list_first_entry_rcu()? 281 * 282 * Implementing those functions following their counterparts list_empty() and 283 * list_first_entry() is not advisable because they lead to subtle race 284 * conditions as the following snippet shows: 285 * 286 * if (!list_empty_rcu(mylist)) { 287 * struct foo *bar = list_first_entry_rcu(mylist, struct foo, list_member); 288 * do_something(bar); 289 * } 290 * 291 * The list may not be empty when list_empty_rcu checks it, but it may be when 292 * list_first_entry_rcu rereads the ->next pointer. 293 * 294 * Rereading the ->next pointer is not a problem for list_empty() and 295 * list_first_entry() because they would be protected by a lock that blocks 296 * writers. 297 * 298 * See list_first_or_null_rcu for an alternative. 299 */ 300 301/** 302 * list_first_or_null_rcu - get the first element from a list 303 * @ptr: the list head to take the element from. 304 * @type: the type of the struct this is embedded in. 305 * @member: the name of the list_head within the struct. 306 * 307 * Note that if the list is empty, it returns NULL. 308 * 309 * This primitive may safely run concurrently with the _rcu list-mutation 310 * primitives such as list_add_rcu() as long as it's guarded by rcu_read_lock(). 311 */ 312#define list_first_or_null_rcu(ptr, type, member) \ 313({ \ 314 struct list_head *__ptr = (ptr); \ 315 struct list_head *__next = READ_ONCE(__ptr->next); \ 316 likely(__ptr != __next) ? list_entry_rcu(__next, type, member) : NULL; \ 317}) 318 319/** 320 * list_next_or_null_rcu - get the first element from a list 321 * @head: the head for the list. 322 * @ptr: the list head to take the next element from. 323 * @type: the type of the struct this is embedded in. 324 * @member: the name of the list_head within the struct. 325 * 326 * Note that if the ptr is at the end of the list, NULL is returned. 327 * 328 * This primitive may safely run concurrently with the _rcu list-mutation 329 * primitives such as list_add_rcu() as long as it's guarded by rcu_read_lock(). 330 */ 331#define list_next_or_null_rcu(head, ptr, type, member) \ 332({ \ 333 struct list_head *__head = (head); \ 334 struct list_head *__ptr = (ptr); \ 335 struct list_head *__next = READ_ONCE(__ptr->next); \ 336 likely(__next != __head) ? list_entry_rcu(__next, type, \ 337 member) : NULL; \ 338}) 339 340/** 341 * list_for_each_entry_rcu - iterate over rcu list of given type 342 * @pos: the type * to use as a loop cursor. 343 * @head: the head for your list. 344 * @member: the name of the list_head within the struct. 345 * 346 * This list-traversal primitive may safely run concurrently with 347 * the _rcu list-mutation primitives such as list_add_rcu() 348 * as long as the traversal is guarded by rcu_read_lock(). 349 */ 350#define list_for_each_entry_rcu(pos, head, member) \ 351 for (pos = list_entry_rcu((head)->next, typeof(*pos), member); \ 352 &pos->member != (head); \ 353 pos = list_entry_rcu(pos->member.next, typeof(*pos), member)) 354 355/** 356 * list_entry_lockless - get the struct for this entry 357 * @ptr: the &struct list_head pointer. 358 * @type: the type of the struct this is embedded in. 359 * @member: the name of the list_head within the struct. 360 * 361 * This primitive may safely run concurrently with the _rcu list-mutation 362 * primitives such as list_add_rcu(), but requires some implicit RCU 363 * read-side guarding. One example is running within a special 364 * exception-time environment where preemption is disabled and where 365 * lockdep cannot be invoked (in which case updaters must use RCU-sched, 366 * as in synchronize_sched(), call_rcu_sched(), and friends). Another 367 * example is when items are added to the list, but never deleted. 368 */ 369#define list_entry_lockless(ptr, type, member) \ 370 container_of((typeof(ptr))lockless_dereference(ptr), type, member) 371 372/** 373 * list_for_each_entry_lockless - iterate over rcu list of given type 374 * @pos: the type * to use as a loop cursor. 375 * @head: the head for your list. 376 * @member: the name of the list_struct within the struct. 377 * 378 * This primitive may safely run concurrently with the _rcu list-mutation 379 * primitives such as list_add_rcu(), but requires some implicit RCU 380 * read-side guarding. One example is running within a special 381 * exception-time environment where preemption is disabled and where 382 * lockdep cannot be invoked (in which case updaters must use RCU-sched, 383 * as in synchronize_sched(), call_rcu_sched(), and friends). Another 384 * example is when items are added to the list, but never deleted. 385 */ 386#define list_for_each_entry_lockless(pos, head, member) \ 387 for (pos = list_entry_lockless((head)->next, typeof(*pos), member); \ 388 &pos->member != (head); \ 389 pos = list_entry_lockless(pos->member.next, typeof(*pos), member)) 390 391/** 392 * list_for_each_entry_continue_rcu - continue iteration over list of given type 393 * @pos: the type * to use as a loop cursor. 394 * @head: the head for your list. 395 * @member: the name of the list_head within the struct. 396 * 397 * Continue to iterate over list of given type, continuing after 398 * the current position. 399 */ 400#define list_for_each_entry_continue_rcu(pos, head, member) \ 401 for (pos = list_entry_rcu(pos->member.next, typeof(*pos), member); \ 402 &pos->member != (head); \ 403 pos = list_entry_rcu(pos->member.next, typeof(*pos), member)) 404 405/** 406 * hlist_del_rcu - deletes entry from hash list without re-initialization 407 * @n: the element to delete from the hash list. 408 * 409 * Note: list_unhashed() on entry does not return true after this, 410 * the entry is in an undefined state. It is useful for RCU based 411 * lockfree traversal. 412 * 413 * In particular, it means that we can not poison the forward 414 * pointers that may still be used for walking the hash list. 415 * 416 * The caller must take whatever precautions are necessary 417 * (such as holding appropriate locks) to avoid racing 418 * with another list-mutation primitive, such as hlist_add_head_rcu() 419 * or hlist_del_rcu(), running on this same list. 420 * However, it is perfectly legal to run concurrently with 421 * the _rcu list-traversal primitives, such as 422 * hlist_for_each_entry(). 423 */ 424static inline void hlist_del_rcu(struct hlist_node *n) 425{ 426 __hlist_del(n); 427 n->pprev = LIST_POISON2; 428} 429 430/** 431 * hlist_replace_rcu - replace old entry by new one 432 * @old : the element to be replaced 433 * @new : the new element to insert 434 * 435 * The @old entry will be replaced with the @new entry atomically. 436 */ 437static inline void hlist_replace_rcu(struct hlist_node *old, 438 struct hlist_node *new) 439{ 440 struct hlist_node *next = old->next; 441 442 new->next = next; 443 new->pprev = old->pprev; 444 rcu_assign_pointer(*(struct hlist_node __rcu **)new->pprev, new); 445 if (next) 446 new->next->pprev = &new->next; 447 old->pprev = LIST_POISON2; 448} 449 450/* 451 * return the first or the next element in an RCU protected hlist 452 */ 453#define hlist_first_rcu(head) (*((struct hlist_node __rcu **)(&(head)->first))) 454#define hlist_next_rcu(node) (*((struct hlist_node __rcu **)(&(node)->next))) 455#define hlist_pprev_rcu(node) (*((struct hlist_node __rcu **)((node)->pprev))) 456 457/** 458 * hlist_add_head_rcu 459 * @n: the element to add to the hash list. 460 * @h: the list to add to. 461 * 462 * Description: 463 * Adds the specified element to the specified hlist, 464 * while permitting racing traversals. 465 * 466 * The caller must take whatever precautions are necessary 467 * (such as holding appropriate locks) to avoid racing 468 * with another list-mutation primitive, such as hlist_add_head_rcu() 469 * or hlist_del_rcu(), running on this same list. 470 * However, it is perfectly legal to run concurrently with 471 * the _rcu list-traversal primitives, such as 472 * hlist_for_each_entry_rcu(), used to prevent memory-consistency 473 * problems on Alpha CPUs. Regardless of the type of CPU, the 474 * list-traversal primitive must be guarded by rcu_read_lock(). 475 */ 476static inline void hlist_add_head_rcu(struct hlist_node *n, 477 struct hlist_head *h) 478{ 479 struct hlist_node *first = h->first; 480 481 n->next = first; 482 n->pprev = &h->first; 483 rcu_assign_pointer(hlist_first_rcu(h), n); 484 if (first) 485 first->pprev = &n->next; 486} 487 488/** 489 * hlist_add_tail_rcu 490 * @n: the element to add to the hash list. 491 * @h: the list to add to. 492 * 493 * Description: 494 * Adds the specified element to the specified hlist, 495 * while permitting racing traversals. 496 * 497 * The caller must take whatever precautions are necessary 498 * (such as holding appropriate locks) to avoid racing 499 * with another list-mutation primitive, such as hlist_add_head_rcu() 500 * or hlist_del_rcu(), running on this same list. 501 * However, it is perfectly legal to run concurrently with 502 * the _rcu list-traversal primitives, such as 503 * hlist_for_each_entry_rcu(), used to prevent memory-consistency 504 * problems on Alpha CPUs. Regardless of the type of CPU, the 505 * list-traversal primitive must be guarded by rcu_read_lock(). 506 */ 507static inline void hlist_add_tail_rcu(struct hlist_node *n, 508 struct hlist_head *h) 509{ 510 struct hlist_node *i, *last = NULL; 511 512 for (i = hlist_first_rcu(h); i; i = hlist_next_rcu(i)) 513 last = i; 514 515 if (last) { 516 n->next = last->next; 517 n->pprev = &last->next; 518 rcu_assign_pointer(hlist_next_rcu(last), n); 519 } else { 520 hlist_add_head_rcu(n, h); 521 } 522} 523 524/** 525 * hlist_add_before_rcu 526 * @n: the new element to add to the hash list. 527 * @next: the existing element to add the new element before. 528 * 529 * Description: 530 * Adds the specified element to the specified hlist 531 * before the specified node while permitting racing traversals. 532 * 533 * The caller must take whatever precautions are necessary 534 * (such as holding appropriate locks) to avoid racing 535 * with another list-mutation primitive, such as hlist_add_head_rcu() 536 * or hlist_del_rcu(), running on this same list. 537 * However, it is perfectly legal to run concurrently with 538 * the _rcu list-traversal primitives, such as 539 * hlist_for_each_entry_rcu(), used to prevent memory-consistency 540 * problems on Alpha CPUs. 541 */ 542static inline void hlist_add_before_rcu(struct hlist_node *n, 543 struct hlist_node *next) 544{ 545 n->pprev = next->pprev; 546 n->next = next; 547 rcu_assign_pointer(hlist_pprev_rcu(n), n); 548 next->pprev = &n->next; 549} 550 551/** 552 * hlist_add_behind_rcu 553 * @n: the new element to add to the hash list. 554 * @prev: the existing element to add the new element after. 555 * 556 * Description: 557 * Adds the specified element to the specified hlist 558 * after the specified node while permitting racing traversals. 559 * 560 * The caller must take whatever precautions are necessary 561 * (such as holding appropriate locks) to avoid racing 562 * with another list-mutation primitive, such as hlist_add_head_rcu() 563 * or hlist_del_rcu(), running on this same list. 564 * However, it is perfectly legal to run concurrently with 565 * the _rcu list-traversal primitives, such as 566 * hlist_for_each_entry_rcu(), used to prevent memory-consistency 567 * problems on Alpha CPUs. 568 */ 569static inline void hlist_add_behind_rcu(struct hlist_node *n, 570 struct hlist_node *prev) 571{ 572 n->next = prev->next; 573 n->pprev = &prev->next; 574 rcu_assign_pointer(hlist_next_rcu(prev), n); 575 if (n->next) 576 n->next->pprev = &n->next; 577} 578 579#define __hlist_for_each_rcu(pos, head) \ 580 for (pos = rcu_dereference(hlist_first_rcu(head)); \ 581 pos; \ 582 pos = rcu_dereference(hlist_next_rcu(pos))) 583 584/** 585 * hlist_for_each_entry_rcu - iterate over rcu list of given type 586 * @pos: the type * to use as a loop cursor. 587 * @head: the head for your list. 588 * @member: the name of the hlist_node within the struct. 589 * 590 * This list-traversal primitive may safely run concurrently with 591 * the _rcu list-mutation primitives such as hlist_add_head_rcu() 592 * as long as the traversal is guarded by rcu_read_lock(). 593 */ 594#define hlist_for_each_entry_rcu(pos, head, member) \ 595 for (pos = hlist_entry_safe (rcu_dereference_raw(hlist_first_rcu(head)),\ 596 typeof(*(pos)), member); \ 597 pos; \ 598 pos = hlist_entry_safe(rcu_dereference_raw(hlist_next_rcu(\ 599 &(pos)->member)), typeof(*(pos)), member)) 600 601/** 602 * hlist_for_each_entry_rcu_notrace - iterate over rcu list of given type (for tracing) 603 * @pos: the type * to use as a loop cursor. 604 * @head: the head for your list. 605 * @member: the name of the hlist_node within the struct. 606 * 607 * This list-traversal primitive may safely run concurrently with 608 * the _rcu list-mutation primitives such as hlist_add_head_rcu() 609 * as long as the traversal is guarded by rcu_read_lock(). 610 * 611 * This is the same as hlist_for_each_entry_rcu() except that it does 612 * not do any RCU debugging or tracing. 613 */ 614#define hlist_for_each_entry_rcu_notrace(pos, head, member) \ 615 for (pos = hlist_entry_safe (rcu_dereference_raw_notrace(hlist_first_rcu(head)),\ 616 typeof(*(pos)), member); \ 617 pos; \ 618 pos = hlist_entry_safe(rcu_dereference_raw_notrace(hlist_next_rcu(\ 619 &(pos)->member)), typeof(*(pos)), member)) 620 621/** 622 * hlist_for_each_entry_rcu_bh - iterate over rcu list of given type 623 * @pos: the type * to use as a loop cursor. 624 * @head: the head for your list. 625 * @member: the name of the hlist_node within the struct. 626 * 627 * This list-traversal primitive may safely run concurrently with 628 * the _rcu list-mutation primitives such as hlist_add_head_rcu() 629 * as long as the traversal is guarded by rcu_read_lock(). 630 */ 631#define hlist_for_each_entry_rcu_bh(pos, head, member) \ 632 for (pos = hlist_entry_safe(rcu_dereference_bh(hlist_first_rcu(head)),\ 633 typeof(*(pos)), member); \ 634 pos; \ 635 pos = hlist_entry_safe(rcu_dereference_bh(hlist_next_rcu(\ 636 &(pos)->member)), typeof(*(pos)), member)) 637 638/** 639 * hlist_for_each_entry_continue_rcu - iterate over a hlist continuing after current point 640 * @pos: the type * to use as a loop cursor. 641 * @member: the name of the hlist_node within the struct. 642 */ 643#define hlist_for_each_entry_continue_rcu(pos, member) \ 644 for (pos = hlist_entry_safe(rcu_dereference_raw(hlist_next_rcu( \ 645 &(pos)->member)), typeof(*(pos)), member); \ 646 pos; \ 647 pos = hlist_entry_safe(rcu_dereference_raw(hlist_next_rcu( \ 648 &(pos)->member)), typeof(*(pos)), member)) 649 650/** 651 * hlist_for_each_entry_continue_rcu_bh - iterate over a hlist continuing after current point 652 * @pos: the type * to use as a loop cursor. 653 * @member: the name of the hlist_node within the struct. 654 */ 655#define hlist_for_each_entry_continue_rcu_bh(pos, member) \ 656 for (pos = hlist_entry_safe(rcu_dereference_bh(hlist_next_rcu( \ 657 &(pos)->member)), typeof(*(pos)), member); \ 658 pos; \ 659 pos = hlist_entry_safe(rcu_dereference_bh(hlist_next_rcu( \ 660 &(pos)->member)), typeof(*(pos)), member)) 661 662/** 663 * hlist_for_each_entry_from_rcu - iterate over a hlist continuing from current point 664 * @pos: the type * to use as a loop cursor. 665 * @member: the name of the hlist_node within the struct. 666 */ 667#define hlist_for_each_entry_from_rcu(pos, member) \ 668 for (; pos; \ 669 pos = hlist_entry_safe(rcu_dereference_raw(hlist_next_rcu( \ 670 &(pos)->member)), typeof(*(pos)), member)) 671 672#endif /* __KERNEL__ */ 673#endif 674