urcu.h

   1 #ifndef _URCU_H
   2 #define _URCU_H
   3
   4 /*
   5  * urcu.h
   6  *
   7  * Userspace RCU header
   8  *
   9  * Copyright February 2009 - Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
  10  *
  11  * Credits for Paul E. McKenney <paulmck@linux.vnet.ibm.com>
  12  * for inspiration coming from the Linux kernel RCU and rcu-preempt.
  13  *
  14  * LGPL-compatible code should include this header with :
  15  *
  16  * #define _LGPL_SOURCE
  17  * #include <urcu.h>
  18  *
  19  * Distributed under LGPLv2.1
  20  *
  21  * IBM's contributions to this file may be relicensed under LGPLv2 or later.
  22  */
  23
  24 #include <stdlib.h>
  25 #include <pthread.h>
  26
  27 #ifdef _LGPL_SOURCE
  28
  29 #include <urcu-static.h>
  30
  31 /*
  32  * Mappings for static use of the userspace RCU library.
  33  * Should only be used in LGPL-compatible code.
  34  */
  35
  36 #define rcu_dereference         _rcu_dereference
  37 #define rcu_read_lock           _rcu_read_lock
  38 #define rcu_read_unlock         _rcu_read_unlock
  39
  40 #define rcu_assign_pointer      _rcu_assign_pointer
  41 #define rcu_xchg_pointer        _rcu_xchg_pointer
  42 #define rcu_publish_content     _rcu_publish_content
  43
  44 #else /* !_LGPL_SOURCE */
  45
  46 /*
  47  * library wrappers to be used by non-LGPL compatible source code.
  48  */
  49
  50 extern void rcu_read_lock(void);
  51 extern void rcu_read_unlock(void);
  52
  53 extern void *rcu_dereference(void *p);
  54
  55 extern void *rcu_assign_pointer_sym(void **p, void *v);
  56
  57 #define rcu_assign_pointer(p, v)                        \
  58         rcu_assign_pointer_sym((void **)(p), (v))
  59
  60 extern void *rcu_xchg_pointer_sym(void **p, void *v);
  61 #define rcu_xchg_pointer(p, v)                          \
  62         rcu_xchg_pointer_sym((void **)(p), (v))
  63
  64 extern void *rcu_publish_content_sym(void **p, void *v);
  65 #define rcu_publish_content(p, v)                       \
  66         rcu_publish_content_sym((void **)(p), (v))
  67
  68 #endif /* !_LGPL_SOURCE */
  69
  70 extern void synchronize_rcu(void);
  71
  72 /*
  73  * Reader thread registration.
  74  */
  75 extern void rcu_register_thread(void);
  76 extern void rcu_unregister_thread(void);
  77
  78 #endif /* _URCU_H */