include/urcu/rculfqueue.h

   1 #ifndef _URCU_RCULFQUEUE_H
   2 #define _URCU_RCULFQUEUE_H
   3
   4 /*
   5  * rculfqueue.h
   6  *
   7  * Userspace RCU library - Lock-Free RCU Queue
   8  *
   9  * Copyright 2010 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
  10  *
  11  * This library is free software; you can redistribute it and/or
  12  * modify it under the terms of the GNU Lesser General Public
  13  * License as published by the Free Software Foundation; either
  14  * version 2.1 of the License, or (at your option) any later version.
  15  *
  16  * This library is distributed in the hope that it will be useful,
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  19  * Lesser General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU Lesser General Public
  22  * License along with this library; if not, write to the Free Software
  23  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  24  */
  25
  26
  27 #ifdef __cplusplus
  28 extern "C" {
  29 #endif
  30
  31 struct cds_lfq_queue_rcu;
  32 struct rcu_head;
  33
  34 struct cds_lfq_node_rcu {
  35         struct cds_lfq_node_rcu *next;
  36         int dummy;
  37 };
  38
  39 struct cds_lfq_queue_rcu {
  40         struct cds_lfq_node_rcu *head, *tail;
  41         void (*queue_call_rcu)(struct rcu_head *head,
  42                 void (*func)(struct rcu_head *head));
  43 };
  44
  45 #ifdef _LGPL_SOURCE
  46
  47 #include <urcu/static/rculfqueue.h>
  48
  49 #define cds_lfq_node_init_rcu           _cds_lfq_node_init_rcu
  50 #define cds_lfq_init_rcu                _cds_lfq_init_rcu
  51 #define cds_lfq_destroy_rcu             _cds_lfq_destroy_rcu
  52 #define cds_lfq_enqueue_rcu             _cds_lfq_enqueue_rcu
  53 #define cds_lfq_dequeue_rcu             _cds_lfq_dequeue_rcu
  54
  55 #else /* !_LGPL_SOURCE */
  56
  57 extern void cds_lfq_node_init_rcu(struct cds_lfq_node_rcu *node);
  58 extern void cds_lfq_init_rcu(struct cds_lfq_queue_rcu *q,
  59                              void queue_call_rcu(struct rcu_head *head,
  60                                         void (*func)(struct rcu_head *head)));
  61 /*
  62  * The queue should be emptied before calling destroy.
  63  *
  64  * Return 0 on success, -EPERM if queue is not empty.
  65  */
  66 extern int cds_lfq_destroy_rcu(struct cds_lfq_queue_rcu *q);
  67
  68 /*
  69  * Should be called under rcu read lock critical section.
  70  */
  71 extern void cds_lfq_enqueue_rcu(struct cds_lfq_queue_rcu *q,
  72                                 struct cds_lfq_node_rcu *node);
  73
  74 /*
  75  * Should be called under rcu read lock critical section.
  76  *
  77  * The caller must wait for a grace period to pass before freeing the returned
  78  * node or modifying the cds_lfq_node_rcu structure.
  79  * Returns NULL if queue is empty.
  80  */
  81 extern
  82 struct cds_lfq_node_rcu *cds_lfq_dequeue_rcu(struct cds_lfq_queue_rcu *q);
  83
  84 #endif /* !_LGPL_SOURCE */
  85
  86 #ifdef __cplusplus
  87 }
  88 #endif
  89
  90 #endif /* _URCU_RCULFQUEUE_H */