urcu.h

   1 #ifndef _URCU_H
   2 #define _URCU_H
   3
   4 /*
   5  * urcu.h
   6  *
   7  * Userspace RCU header
   8  *
   9  * Copyright (c) 2009 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
  10  * Copyright (c) 2009 Paul E. McKenney, IBM Corporation.
  11  *
  12  * LGPL-compatible code should include this header with :
  13  *
  14  * #define _LGPL_SOURCE
  15  * #include <urcu.h>
  16  *
  17  * This library is free software; you can redistribute it and/or
  18  * modify it under the terms of the GNU Lesser General Public
  19  * License as published by the Free Software Foundation; either
  20  * version 2.1 of the License, or (at your option) any later version.
  21  *
  22  * This library is distributed in the hope that it will be useful,
  23  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  24  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  25  * Lesser General Public License for more details.
  26  *
  27  * You should have received a copy of the GNU Lesser General Public
  28  * License along with this library; if not, write to the Free Software
  29  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  30  *
  31  * IBM's contributions to this file may be relicensed under LGPLv2 or later.
  32  */
  33
  34 #include <stdlib.h>
  35 #include <pthread.h>
  36
  37 /*
  38  * See urcu-pointer.h and urcu/static/urcu-pointer.h for pointer
  39  * publication headers.
  40  */
  41 #include <urcu-pointer.h>
  42
  43 #ifdef __cplusplus
  44 extern "C" {
  45 #endif
  46
  47 #include <urcu/map/urcu.h>
  48
  49 /*
  50  * Important !
  51  *
  52  * Each thread containing read-side critical sections must be registered
  53  * with rcu_register_thread_mb() before calling rcu_read_lock_mb().
  54  * rcu_unregister_thread_mb() should be called before the thread exits.
  55  */
  56
  57 #ifdef _LGPL_SOURCE
  58
  59 #include <urcu/static/urcu.h>
  60
  61 /*
  62  * Mappings for static use of the userspace RCU library.
  63  * Should only be used in LGPL-compatible code.
  64  */
  65
  66 /*
  67  * rcu_read_lock()
  68  * rcu_read_unlock()
  69  *
  70  * Mark the beginning and end of a read-side critical section.
  71  * DON'T FORGET TO USE RCU_REGISTER/UNREGISTER_THREAD() FOR EACH THREAD WITH
  72  * READ-SIDE CRITICAL SECTION.
  73  */
  74 #ifdef RCU_MEMBARRIER
  75 #define rcu_read_lock_memb              _rcu_read_lock
  76 #define rcu_read_unlock_memb            _rcu_read_unlock
  77 #define rcu_read_ongoing_memb           _rcu_read_ongoing
  78 #elif defined(RCU_SIGNAL)
  79 #define rcu_read_lock_sig               _rcu_read_lock
  80 #define rcu_read_unlock_sig             _rcu_read_unlock
  81 #define rcu_read_ongoing_sig            _rcu_read_ongoing
  82 #elif defined(RCU_MB)
  83 #define rcu_read_lock_mb                _rcu_read_lock
  84 #define rcu_read_unlock_mb              _rcu_read_unlock
  85 #define rcu_read_ongoing_mb             _rcu_read_ongoing
  86 #endif
  87
  88 #else /* !_LGPL_SOURCE */
  89
  90 /*
  91  * library wrappers to be used by non-LGPL compatible source code.
  92  * See LGPL-only urcu/static/urcu-pointer.h for documentation.
  93  */
  94
  95 extern void rcu_read_lock(void);
  96 extern void rcu_read_unlock(void);
  97 extern int rcu_read_ongoing(void);
  98
  99 #endif /* !_LGPL_SOURCE */
 100
 101 extern void synchronize_rcu(void);
 102
 103 /*
 104  * Reader thread registration.
 105  */
 106 extern void rcu_register_thread(void);
 107 extern void rcu_unregister_thread(void);
 108
 109 /*
 110  * Explicit rcu initialization, for "early" use within library constructors.
 111  */
 112 extern void rcu_init(void);
 113
 114 /*
 115  * Q.S. reporting are no-ops for these URCU flavors.
 116  */
 117 static inline void rcu_quiescent_state(void)
 118 {
 119 }
 120
 121 static inline void rcu_thread_offline(void)
 122 {
 123 }
 124
 125 static inline void rcu_thread_online(void)
 126 {
 127 }
 128
 129 #ifdef __cplusplus
 130 }
 131 #endif
 132
 133 #include <urcu-call-rcu.h>
 134 #include <urcu-defer.h>
 135 #include <urcu-flavor.h>
 136
 137 #endif /* _URCU_H */