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 #include <assert.h>
  27 #include <urcu-call-rcu.h>
  28
  29 #ifdef __cplusplus
  30 extern "C" {
  31 #endif
  32
  33 struct cds_lfq_queue_rcu;
  34
  35 struct cds_lfq_node_rcu {
  36         struct cds_lfq_node_rcu *next;
  37         int dummy;
  38 };
  39
  40 struct cds_lfq_queue_rcu {
  41         struct cds_lfq_node_rcu *head, *tail;
  42         void (*queue_call_rcu)(struct rcu_head *head,
  43                 void (*func)(struct rcu_head *head));
  44 };
  45
  46 #ifdef _LGPL_SOURCE
  47
  48 #include <urcu/static/rculfqueue.h>
  49
  50 #define cds_lfq_node_init_rcu           _cds_lfq_node_init_rcu
  51 #define cds_lfq_init_rcu                _cds_lfq_init_rcu
  52 #define cds_lfq_destroy_rcu             _cds_lfq_destroy_rcu
  53 #define cds_lfq_enqueue_rcu             _cds_lfq_enqueue_rcu
  54 #define cds_lfq_dequeue_rcu             _cds_lfq_dequeue_rcu
  55
  56 #else /* !_LGPL_SOURCE */
  57
  58 extern void cds_lfq_node_init_rcu(struct cds_lfq_node_rcu *node);
  59 extern void cds_lfq_init_rcu(struct cds_lfq_queue_rcu *q,
  60                              void queue_call_rcu(struct rcu_head *head,
  61                                         void (*func)(struct rcu_head *head)));
  62 /*
  63  * The queue should be emptied before calling destroy.
  64  *
  65  * Return 0 on success, -EPERM if queue is not empty.
  66  */
  67 extern int cds_lfq_destroy_rcu(struct cds_lfq_queue_rcu *q);
  68
  69 /*
  70  * Should be called under rcu read lock critical section.
  71  */
  72 extern void cds_lfq_enqueue_rcu(struct cds_lfq_queue_rcu *q,
  73                                 struct cds_lfq_node_rcu *node);
  74
  75 /*
  76  * Should be called under rcu read lock critical section.
  77  *
  78  * The caller must wait for a grace period to pass before freeing the returned
  79  * node or modifying the cds_lfq_node_rcu structure.
  80  * Returns NULL if queue is empty.
  81  */
  82 extern
  83 struct cds_lfq_node_rcu *cds_lfq_dequeue_rcu(struct cds_lfq_queue_rcu *q);
  84
  85 #endif /* !_LGPL_SOURCE */
  86
  87 #ifdef __cplusplus
  88 }
  89 #endif
  90
  91 #endif /* _URCU_RCULFQUEUE_H */