urcu-bp.h

   1 #ifndef _URCU_BP_H
   2 #define _URCU_BP_H
   3
   4 /*
   5  * urcu-bp.h
   6  *
   7  * Userspace RCU header, "bulletproof" version.
   8  *
   9  * Slower RCU read-side adapted for tracing library. Does not require thread
  10  * registration nor unregistration. Also signal-safe.
  11  *
  12  * Copyright (c) 2009 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
  13  * Copyright (c) 2009 Paul E. McKenney, IBM Corporation.
  14  *
  15  * LGPL-compatible code should include this header with :
  16  *
  17  * #define _LGPL_SOURCE
  18  * #include <urcu.h>
  19  *
  20  * This library is free software; you can redistribute it and/or
  21  * modify it under the terms of the GNU Lesser General Public
  22  * License as published by the Free Software Foundation; either
  23  * version 2.1 of the License, or (at your option) any later version.
  24  *
  25  * This library is distributed in the hope that it will be useful,
  26  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  27  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  28  * Lesser General Public License for more details.
  29  *
  30  * You should have received a copy of the GNU Lesser General Public
  31  * License along with this library; if not, write to the Free Software
  32  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  33  *
  34  * IBM's contributions to this file may be relicensed under LGPLv2 or later.
  35  */
  36
  37 #include <stdlib.h>
  38 #include <pthread.h>
  39
  40 /*
  41  * See urcu-pointer.h and urcu/static/urcu-pointer.h for pointer
  42  * publication headers.
  43  */
  44 #include <urcu-pointer.h>
  45
  46 #ifdef __cplusplus
  47 extern "C" {
  48 #endif
  49
  50 #include <urcu/map/urcu-bp.h>
  51
  52 /*
  53  * Important !
  54  *
  55  * Each thread containing read-side critical sections must be registered
  56  * with rcu_register_thread() before calling rcu_read_lock().
  57  * rcu_unregister_thread() should be called before the thread exits.
  58  */
  59
  60 #ifdef _LGPL_SOURCE
  61
  62 #include <urcu/static/urcu-bp.h>
  63
  64 /*
  65  * Mappings for static use of the userspace RCU library.
  66  * Should only be used in LGPL-compatible code.
  67  */
  68
  69 /*
  70  * rcu_read_lock()
  71  * rcu_read_unlock()
  72  *
  73  * Mark the beginning and end of a read-side critical section.
  74  */
  75 #define rcu_read_lock_bp                _rcu_read_lock
  76 #define rcu_read_unlock_bp              _rcu_read_unlock
  77
  78 #else /* !_LGPL_SOURCE */
  79
  80 /*
  81  * library wrappers to be used by non-LGPL compatible source code.
  82  * See LGPL-only urcu/static/urcu-pointer.h for documentation.
  83  */
  84
  85 extern void rcu_read_lock(void);
  86 extern void rcu_read_unlock(void);
  87
  88 #endif /* !_LGPL_SOURCE */
  89
  90 extern void synchronize_rcu(void);
  91
  92 /*
  93  * rcu_bp_before_fork, rcu_bp_after_fork_parent and rcu_bp_after_fork_child
  94  * should be called around fork() system calls when the child process is not
  95  * expected to immediately perform an exec(). For pthread users, see
  96  * pthread_atfork(3).
  97  */
  98 extern void rcu_bp_before_fork(void);
  99 extern void rcu_bp_after_fork_parent(void);
 100 extern void rcu_bp_after_fork_child(void);
 101
 102 /*
 103  * In the bulletproof version, the following functions are no-ops.
 104  */
 105 static inline void rcu_register_thread(void)
 106 {
 107 }
 108
 109 static inline void rcu_unregister_thread(void)
 110 {
 111 }
 112
 113 static inline void rcu_init(void)
 114 {
 115 }
 116
 117 /*
 118  * Q.S. reporting are no-ops for these URCU flavors.
 119  */
 120 static inline void rcu_quiescent_state(void)
 121 {
 122 }
 123
 124 static inline void rcu_thread_offline(void)
 125 {
 126 }
 127
 128 static inline void rcu_thread_online(void)
 129 {
 130 }
 131
 132 #ifdef __cplusplus
 133 }
 134 #endif
 135
 136 #include <urcu-call-rcu.h>
 137 #include <urcu-defer.h>
 138
 139 #endif /* _URCU_BP_H */