| 1 | /* |
| 2 | * Copyright (C) 2002 Free Software Foundation, Inc. |
| 3 | * (originally part of the GNU C Library) |
| 4 | * Contributed by Ulrich Drepper <drepper@redhat.com>, 2002. |
| 5 | * |
| 6 | * Copyright (C) 2009 Pierre-Marc Fournier |
| 7 | * Conversion to RCU list. |
| 8 | * Copyright (C) 2010 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> |
| 9 | * |
| 10 | * This library is free software; you can redistribute it and/or |
| 11 | * modify it under the terms of the GNU Lesser General Public |
| 12 | * License as published by the Free Software Foundation; either |
| 13 | * version 2.1 of the License, or (at your option) any later version. |
| 14 | * |
| 15 | * This library is distributed in the hope that it will be useful, |
| 16 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 17 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 18 | * Lesser General Public License for more details. |
| 19 | * |
| 20 | * You should have received a copy of the GNU Lesser General Public |
| 21 | * License along with this library; if not, write to the Free Software |
| 22 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| 23 | */ |
| 24 | |
| 25 | #ifndef _URCU_RCULIST_H |
| 26 | #define _URCU_RCULIST_H |
| 27 | |
| 28 | #include <urcu/list.h> |
| 29 | #include <urcu/arch.h> |
| 30 | #include <urcu-pointer.h> |
| 31 | |
| 32 | /* Add new element at the head of the list. |
| 33 | */ |
| 34 | static inline void cds_list_add_rcu(struct cds_list_head *newp, struct cds_list_head *head) |
| 35 | { |
| 36 | newp->next = head->next; |
| 37 | newp->prev = head; |
| 38 | cmm_smp_wmb(); |
| 39 | head->next->prev = newp; |
| 40 | head->next = newp; |
| 41 | } |
| 42 | |
| 43 | /* replace an old entry atomically. |
| 44 | */ |
| 45 | static inline void cds_list_replace_rcu(struct cds_list_head *old, struct cds_list_head *_new) |
| 46 | { |
| 47 | _new->next = old->next; |
| 48 | _new->prev = old->prev; |
| 49 | rcu_assign_pointer(_new->prev->next, _new); |
| 50 | _new->next->prev = _new; |
| 51 | } |
| 52 | |
| 53 | /* Remove element from list. */ |
| 54 | static inline void cds_list_del_rcu(struct cds_list_head *elem) |
| 55 | { |
| 56 | elem->next->prev = elem->prev; |
| 57 | elem->prev->next = elem->next; |
| 58 | } |
| 59 | |
| 60 | /* |
| 61 | * Iteration through all elements of the list must be done while rcu_read_lock() |
| 62 | * is held. |
| 63 | */ |
| 64 | |
| 65 | /* Iterate forward over the elements of the list. */ |
| 66 | #define cds_list_for_each_rcu(pos, head) \ |
| 67 | for (pos = rcu_dereference((head)->next); pos != (head); \ |
| 68 | pos = rcu_dereference(pos->next)) |
| 69 | |
| 70 | |
| 71 | /* Iterate through elements of the list. |
| 72 | */ |
| 73 | #define cds_list_for_each_entry_rcu(pos, head, member) \ |
| 74 | for (pos = cds_list_entry(rcu_dereference((head)->next), __typeof__(*pos), member); \ |
| 75 | &pos->member != (head); \ |
| 76 | pos = cds_list_entry(rcu_dereference(pos->member.next), __typeof__(*pos), member)) |
| 77 | |
| 78 | #endif /* _URCU_RCULIST_H */ |