2 This file is a part of libcds - Concurrent Data Structures library
4 (C) Copyright Maxim Khizhinsky (libcds.dev@gmail.com) 2006-2016
6 Source code repo: http://github.com/khizmax/libcds/
7 Download: http://sourceforge.net/projects/libcds/files/
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10 modification, are permitted provided that the following conditions are met:
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13 list of conditions and the following disclaimer.
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16 this list of conditions and the following disclaimer in the documentation
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31 #ifndef CDSLIB_URCU_DETAILS_GPI_H
32 #define CDSLIB_URCU_DETAILS_GPI_H
35 #include <cds/urcu/details/gp.h>
36 #include <cds/algo/backoff_strategy.h>
38 namespace cds { namespace urcu {
40 /// User-space general-purpose RCU with immediate reclamation
42 @headerfile cds/urcu/general_instant.h
44 This is simplest general-purpose RCU implementation. When a thread calls \ref retire_ptr function
45 the RCU \p synchronize function is called that waits until all reader/updater threads end up
46 their read-side critical sections, i.e. until the RCU quiescent state will come.
47 After that the retired object is freed immediately.
48 Thus, the implementation blocks for any retired object
50 There is a wrapper \ref cds_urcu_general_instant_gc "gc<general_instant>" for \p %general_instant class
51 that provides unified RCU interface. You should use this wrapper class instead \p %general_instant
54 - \p Lock - mutex type, default is \p std::mutex
55 - \p Backoff - back-off schema, default is cds::backoff::Default
58 class Lock = std::mutex
59 ,class Backoff = cds::backoff::Default
61 class general_instant: public details::gp_singleton< general_instant_tag >
64 typedef details::gp_singleton< general_instant_tag > base_class;
68 typedef general_instant_tag rcu_tag ; ///< RCU tag
69 typedef Lock lock_type ; ///< Lock type
70 typedef Backoff back_off ; ///< Back-off schema type
72 typedef typename base_class::thread_gc thread_gc ; ///< Thread-side RCU part
73 typedef typename thread_gc::scoped_lock scoped_lock ; ///< Access lock class
75 static bool const c_bBuffered = false ; ///< This RCU does not buffer disposed elements
79 typedef details::gp_singleton_instance< rcu_tag > singleton_ptr;
88 /// Returns singleton instance
89 static general_instant * instance()
91 return static_cast<general_instant *>( base_class::instance());
94 /// Checks if the singleton is created and ready to use
97 return singleton_ptr::s_pRCU != nullptr;
110 base_class::flip_and_wait( bkoff );
115 /// Creates singleton object
116 static void Construct()
118 if ( !singleton_ptr::s_pRCU )
119 singleton_ptr::s_pRCU = new general_instant();
122 /// Destroys singleton object
123 static void Destruct( bool bDetachAll = false )
127 instance()->m_ThreadList.detach_all();
129 singleton_ptr::s_pRCU = nullptr;
134 /// Retires \p p pointer
136 The method calls \p synchronize() to wait for the end of grace period
137 and calls \p p disposer.
139 virtual void retire_ptr( retired_ptr& p )
146 /// Retires the pointer chain [\p itFirst, \p itLast)
147 template <typename ForwardIterator>
148 void batch_retire( ForwardIterator itFirst, ForwardIterator itLast )
150 if ( itFirst != itLast ) {
152 while ( itFirst != itLast ) {
153 retired_ptr p( *itFirst );
161 /// Retires the pointer chain until \p Func returns \p nullptr retired pointer
162 template <typename Func>
163 void batch_retire( Func e )
165 retired_ptr p{ e() };
176 /// Waits to finish a grace period
179 assert( !thread_gc::is_locked());
180 std::unique_lock<lock_type> sl( m_Lock );
186 // Added for uniformity
187 size_t CDS_CONSTEXPR capacity() const
194 }} // namespace cds::urcu
196 #endif // #ifndef CDSLIB_URCU_DETAILS_GPI_H