Merged 44636, 44640, 45094 (atomic access) from trunk to release.

[SVN r47349]

include/boost/memory_order.hpp

@@ -0,0 +1,35 @@
+#ifndef BOOST_MEMORY_ORDER_HPP_INCLUDED
+#define BOOST_MEMORY_ORDER_HPP_INCLUDED
+
+// MS compatible compilers support #pragma once
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1020)
+# pragma once
+#endif
+
+//  boost/memory_order.hpp
+//
+//  Defines enum boost::memory_order per the C++0x working draft
+//
+//  Copyright (c) 2008 Peter Dimov
+//
+//  Distributed under the Boost Software License, Version 1.0.
+//  See accompanying file LICENSE_1_0.txt or copy at
+//  http://www.boost.org/LICENSE_1_0.txt)
+
+
+namespace boost
+{
+
+enum memory_order
+{
+    memory_order_relaxed = 0,
+    memory_order_acquire = 1,
+    memory_order_release = 2,
+    memory_order_acq_rel = 3, // acquire | release
+    memory_order_seq_cst = 7, // acq_rel | 4
+};
+
+} // namespace boost
+
+#endif // #ifndef BOOST_MEMORY_ORDER_HPP_INCLUDED

include/boost/shared_ptr.hpp

@@ -33,6 +33,11 @@
 #include <boost/detail/workaround.hpp>
 #include <boost/detail/sp_convertible.hpp>
 
+#if !defined(BOOST_SP_NO_ATOMIC_ACCESS)
+#include <boost/detail/spinlock_pool.hpp>
+#include <boost/memory_order.hpp>
+#endif
+
 #include <algorithm>            // for std::swap
 #include <functional>           // for std::less
 #include <typeinfo>             // for std::bad_cast
@@ -498,6 +503,65 @@ public:
         return pn.get_deleter( ti );
     }
 
+    // atomic access
+
+#if !defined(BOOST_SP_NO_ATOMIC_ACCESS)
+
+    shared_ptr<T> atomic_load( memory_order /*mo*/ = memory_order_seq_cst ) const
+    {
+        boost::detail::spinlock_pool<2>::scoped_lock lock( this );
+        return *this;
+    }
+
+    void atomic_store( shared_ptr<T> r, memory_order /*mo*/ = memory_order_seq_cst )
+    {
+        boost::detail::spinlock_pool<2>::scoped_lock lock( this );
+        swap( r );
+    }
+
+    shared_ptr<T> atomic_swap( shared_ptr<T> r, memory_order /*mo*/ = memory_order_seq_cst )
+    {
+        boost::detail::spinlock & sp = boost::detail::spinlock_pool<2>::spinlock_for( this );
+
+        sp.lock();
+        swap( r );
+        sp.unlock();
+
+        return r; // return std::move(r)
+    }
+
+    bool atomic_compare_swap( shared_ptr<T> & v, shared_ptr<T> w )
+    {
+        boost::detail::spinlock & sp = boost::detail::spinlock_pool<2>::spinlock_for( this );
+
+        sp.lock();
+
+        if( px == v.px && pn == v.pn )
+        {
+            swap( w );
+
+            sp.unlock();
+
+            return true;
+        }
+        else
+        {
+            shared_ptr tmp( *this );
+
+            sp.unlock();
+
+            tmp.swap( v );
+            return false;
+        }
+    }
+
+    inline bool atomic_compare_swap( shared_ptr<T> & v, shared_ptr<T> w, memory_order /*success*/, memory_order /*failure*/ )
+    {
+        return atomic_compare_swap( v, w ); // std::move( w )
+    }
+
+#endif
+
 // Tasteless as this may seem, making all members public allows member templates
 // to work in the absence of member template friends. (Matthew Langston)
 

test/Jamfile.v2

@@ -47,5 +47,6 @@ import testing ;
           [ run wp_convertible_test.cpp ]
           [ run ip_convertible_test.cpp ]
           [ run allocate_shared_test.cpp ]
+          [ run sp_atomic_test.cpp ]
         ;
 }

test/sp_atomic_mt2_test.cpp

@@ -0,0 +1,247 @@
+
+// Copyright (c) 2008 Peter Dimov
+//
+// Distributed under the Boost Software License, Version 1.0.
+// See accompanying file LICENSE_1_0.txt or copy at
+// http://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/config.hpp>
+
+#include <boost/shared_ptr.hpp>
+#include <boost/bind.hpp>
+
+#include <boost/thread/shared_mutex.hpp>
+#include <boost/thread/locks.hpp>
+
+#include <boost/detail/lightweight_mutex.hpp>
+#include <boost/detail/lightweight_thread.hpp>
+
+#include <vector>
+#include <numeric>
+#include <cstdio>
+#include <cstdlib>
+#include <cstddef>
+#include <ctime>
+
+//
+
+static void next_value( unsigned & v )
+{
+    v = v % 2? 3 * v + 1: v / 2;
+}
+
+struct X
+{
+    std::vector<unsigned> v_;
+
+    explicit X( std::size_t n ): v_( n )
+    {
+        for( std::size_t i = 0; i < n; ++i )
+        {
+            v_[ i ] = i;
+        }
+    }
+
+    unsigned get() const
+    {
+        return std::accumulate( v_.begin(), v_.end(), 0 );
+    }
+
+    void set()
+    {
+        std::for_each( v_.begin(), v_.end(), next_value );
+    }
+};
+
+static boost::shared_ptr<X> ps;
+
+static boost::detail::lightweight_mutex lm;
+static boost::shared_mutex rw;
+
+enum prim_type
+{
+    pt_mutex,
+    pt_rwlock,
+    pt_atomics
+};
+
+int read_access( prim_type pt )
+{
+    switch( pt )
+    {
+    case pt_mutex:
+        {
+            boost::detail::lightweight_mutex::scoped_lock lock( lm );
+            return ps->get();
+        }
+
+    case pt_rwlock:
+        {
+            boost::shared_lock<boost::shared_mutex> lock( rw );
+            return ps->get();
+        }
+
+    case pt_atomics:
+        {
+            boost::shared_ptr<X> p2 = ps.atomic_load();
+            return p2->get();
+        }
+    }
+}
+
+void write_access( prim_type pt )
+{
+    switch( pt )
+    {
+    case pt_mutex:
+        {
+            boost::detail::lightweight_mutex::scoped_lock lock( lm );
+            ps->set();
+        }
+        break;
+
+    case pt_rwlock:
+        {
+            boost::unique_lock<boost::shared_mutex> lock( rw );
+            ps->set();
+        }
+        break;
+
+    case pt_atomics:
+        {
+            boost::shared_ptr<X> p1 = ps.atomic_load();
+
+            for( ;; )
+            {
+                boost::shared_ptr<X> p2( new X( *p1 ) );
+                p2->set();
+
+                if( ps.atomic_compare_swap( p1, p2 ) ) break;
+            }
+        }
+        break;
+    }
+}
+
+void worker( int k, prim_type pt, int n, int r )
+{
+    ++r;
+
+    unsigned s = 0, nr = 0, nw = 0;
+
+    for( int i = 0; i < n; ++i )
+    {
+        if( i % r )
+        {
+            s += read_access( pt );
+            ++nr;
+        }
+        else
+        {
+            write_access( pt );
+            ++s;
+            ++nw;
+        }
+    }
+
+    printf( "Worker %2d: %u:%u, %10u\n", k, nr, nw, s );
+}
+
+#if defined( BOOST_HAS_PTHREADS )
+  char const * thmodel = "POSIX";
+#else
+  char const * thmodel = "Windows";
+#endif
+
+char const * pt_to_string( prim_type pt )
+{
+    switch( pt )
+    {
+    case pt_mutex:
+
+        return "mutex";
+
+    case pt_rwlock:
+
+        return "rwlock";
+
+    case pt_atomics:
+
+        return "atomics";
+    }
+}
+
+static void handle_pt_option( std::string const & opt, prim_type & pt, prim_type pt2 )
+{
+    if( opt == pt_to_string( pt2 ) )
+    {
+        pt = pt2;
+    }
+}
+
+static void handle_int_option( std::string const & opt, std::string const & prefix, int & k, int kmin, int kmax )
+{
+    if( opt.substr( 0, prefix.size() ) == prefix )
+    {
+        int v = atoi( opt.substr( prefix.size() ).c_str() );
+
+        if( v >= kmin && v <= kmax )
+        {
+            k = v;
+        }
+    }
+}
+
+int main( int ac, char const * av[] )
+{
+    using namespace std; // printf, clock_t, clock
+
+    int m = 4;          // threads
+    int n = 10000;      // vector size
+    int k = 1000000;    // iterations
+    int r = 100;        // read/write ratio, r:1
+
+    prim_type pt = pt_atomics;
+
+    for( int i = 1; i < ac; ++i )
+    {
+        handle_pt_option( av[i], pt, pt_mutex );
+        handle_pt_option( av[i], pt, pt_rwlock );
+        handle_pt_option( av[i], pt, pt_atomics );
+
+        handle_int_option( av[i], "n=", n, 1, INT_MAX );
+        handle_int_option( av[i], "size=", n, 1, INT_MAX );
+
+        handle_int_option( av[i], "k=", k, 1, INT_MAX );
+        handle_int_option( av[i], "iterations=", k, 1, INT_MAX );
+
+        handle_int_option( av[i], "m=", m, 1, INT_MAX );
+        handle_int_option( av[i], "threads=", m, 1, INT_MAX );
+
+        handle_int_option( av[i], "r=", r, 1, INT_MAX );
+        handle_int_option( av[i], "ratio=", r, 1, INT_MAX );
+    }
+
+    printf( "%s: threads=%d size=%d iterations=%d ratio=%d %s\n\n", thmodel, m, n, k, r, pt_to_string( pt ) );
+
+    ps.reset( new X( n ) );
+
+    clock_t t = clock();
+
+    std::vector<pthread_t> a( m );
+
+    for( int i = 0; i < m; ++i )
+    {
+        boost::detail::lw_thread_create( a[ i ], boost::bind( worker, i, pt, k, r ) );
+    }
+
+    for( int j = 0; j < m; ++j )
+    {
+        pthread_join( a[ j ], 0 );
+    }
+
+    t = clock() - t;
+
+    double ts = static_cast<double>( t ) / CLOCKS_PER_SEC;
+    printf( "%.3f seconds, %.3f accesses per microsecond.\n", ts, m * k / ts / 1e+6 );
+}

test/sp_atomic_mt_test.cpp

@@ -0,0 +1,191 @@
+
+// Copyright (c) 2008 Peter Dimov
+//
+// Distributed under the Boost Software License, Version 1.0.
+// See accompanying file LICENSE_1_0.txt or copy at
+// http://www.boost.org/LICENSE_1_0.txt
+
+//#define USE_MUTEX
+//#define USE_RWLOCK
+
+#include <boost/config.hpp>
+
+#include <boost/shared_ptr.hpp>
+#include <boost/bind.hpp>
+
+#if defined( USE_RWLOCK )
+#include <boost/thread/shared_mutex.hpp>
+#include <boost/thread/locks.hpp>
+#endif
+
+#include <boost/detail/lightweight_mutex.hpp>
+#include <boost/detail/lightweight_test.hpp>
+#include <boost/detail/lightweight_thread.hpp>
+
+#include <cstdio>
+#include <ctime>
+
+//
+
+int const n = 1024 * 1024;
+
+struct X
+{
+    int v_; // version
+
+    unsigned a_;
+    unsigned b_;
+
+    X(): v_( 0 ), a_( 1 ), b_( 1 )
+    {
+    }
+
+    int get() const
+    {
+        return a_ * 7 + b_ * 11;
+    }
+
+    void set()
+    {
+        int tmp = get();
+
+        b_ = a_;
+        a_ = tmp;
+
+        ++v_;
+    }
+};
+
+static boost::shared_ptr<X> ps( new X );
+
+static boost::detail::lightweight_mutex lm;
+
+#if defined( USE_RWLOCK )
+static boost::shared_mutex rw;
+#endif
+
+static int tr = 0;
+
+void reader( int r )
+{
+    int k = 0;
+    unsigned s = 0;
+
+    for( int i = 0; i < n; ++k )
+    {
+#if defined( USE_MUTEX )
+
+        boost::detail::lightweight_mutex::scoped_lock lock( lm );
+
+        s += ps->get();
+
+        BOOST_TEST( ps->v_ >= i );
+        i = ps->v_;
+
+#elif defined( USE_RWLOCK )
+
+        boost::shared_lock<boost::shared_mutex> lock( rw );
+
+        s += ps->get();
+
+        BOOST_TEST( ps->v_ >= i );
+        i = ps->v_;
+
+#else
+
+        boost::shared_ptr<X> p2 = ps.atomic_load();
+
+        s += p2->get();
+
+        BOOST_TEST( p2->v_ >= i );
+        i = p2->v_;
+
+#endif
+    }
+
+    printf( "Reader %d: %9d iterations (%6.3fx), %u\n", r, k, (double)k / n, s );
+
+    boost::detail::lightweight_mutex::scoped_lock lock( lm );
+    tr += k;
+}
+
+void writer()
+{
+    for( int i = 0; i < n; ++i )
+    {
+#if defined( USE_MUTEX )
+
+        boost::detail::lightweight_mutex::scoped_lock lock( lm );
+
+        BOOST_TEST( ps->v_ == i );
+        ps->set();
+
+#elif defined( USE_RWLOCK )
+
+        boost::unique_lock<boost::shared_mutex> lock( rw );
+
+        BOOST_TEST( ps->v_ == i );
+        ps->set();
+
+#else
+
+        boost::shared_ptr<X> p2( new X( *ps ) );
+
+        BOOST_TEST( p2->v_ == i );
+        p2->set();
+
+        ps.atomic_store( p2 );
+
+#endif
+    }
+}
+
+#if defined( BOOST_HAS_PTHREADS )
+  char const * thmodel = "POSIX";
+#else
+  char const * thmodel = "Windows";
+#endif
+
+int const mr = 8; // reader threads
+int const mw = 1; // writer thread
+
+#if defined( USE_MUTEX )
+  char const * prim = "mutex";
+#elif defined( USE_RWLOCK )
+  char const * prim = "rwlock";
+#else
+  char const * prim = "atomics";
+#endif
+
+int main()
+{
+    using namespace std; // printf, clock_t, clock
+
+    printf( "Using %s threads: %dR + %dW threads, %d iterations, %s\n\n", thmodel, mr, mw, n, prim );
+
+    clock_t t = clock();
+
+    pthread_t a[ mr+mw ];
+
+    for( int i = 0; i < mr; ++i )
+    {
+        boost::detail::lw_thread_create( a[ i ], boost::bind( reader, i ) );
+    }
+
+    for( int i = mr; i < mr+mw; ++i )
+    {
+        boost::detail::lw_thread_create( a[ i ], writer );
+    }
+
+    for( int j = 0; j < mr+mw; ++j )
+    {
+        pthread_join( a[ j ], 0 );
+    }
+
+    t = clock() - t;
+
+    double ts = static_cast<double>( t ) / CLOCKS_PER_SEC;
+    printf( "%.3f seconds, %.3f reads per microsecond.\n", ts, tr / ts / 1e+6 );
+
+    return boost::report_errors();
+}

test/sp_atomic_test.cpp

@@ -0,0 +1,87 @@
+#include <boost/config.hpp>
+
+//  sp_atomic_test.cpp
+//
+//  Copyright (c) 2008 Peter Dimov
+//
+//  Distributed under the Boost Software License, Version 1.0.
+//  See accompanying file LICENSE_1_0.txt or copy at
+//  http://www.boost.org/LICENSE_1_0.txt
+
+
+#include <boost/detail/lightweight_test.hpp>
+#include <boost/shared_ptr.hpp>
+
+//
+
+struct X
+{
+};
+
+#define BOOST_TEST_SP_EQ( p, q ) BOOST_TEST( p == q && !( p < q ) && !( q < p ) )
+
+int main()
+{
+    boost::shared_ptr<X> px( new X );
+
+    {
+        boost::shared_ptr<X> p2 = px.atomic_load();
+        BOOST_TEST_SP_EQ( p2, px );
+
+        boost::shared_ptr<X> px2( new X );
+        px.atomic_store( px2 );
+        BOOST_TEST_SP_EQ( px, px2 );
+
+        p2 = px.atomic_load();
+        BOOST_TEST_SP_EQ( p2, px );
+        BOOST_TEST_SP_EQ( p2, px2 );
+
+        boost::shared_ptr<X> px3( new X );
+        boost::shared_ptr<X> p3 = px.atomic_swap( px3 );
+        BOOST_TEST_SP_EQ( p3, px2 );
+        BOOST_TEST_SP_EQ( px, px3 );
+
+        boost::shared_ptr<X> px4( new X );
+        boost::shared_ptr<X> cmp;
+
+        bool r = px.atomic_compare_swap( cmp, px4 );
+        BOOST_TEST( !r );
+        BOOST_TEST_SP_EQ( px, px3 );
+        BOOST_TEST_SP_EQ( cmp, px3 );
+
+        r = px.atomic_compare_swap( cmp, px4 );
+        BOOST_TEST( r );
+        BOOST_TEST_SP_EQ( px, px4 );
+    }
+
+    //
+
+    px.reset();
+
+    {
+        boost::shared_ptr<X> p2 = px.atomic_load( boost::memory_order_acquire );
+        BOOST_TEST_SP_EQ( p2, px );
+
+        boost::shared_ptr<X> px2( new X );
+        px.atomic_store( px2, boost::memory_order_release );
+        BOOST_TEST_SP_EQ( px, px2 );
+
+        boost::shared_ptr<X> p3 = px.atomic_swap( boost::shared_ptr<X>(), boost::memory_order_acq_rel );
+        BOOST_TEST_SP_EQ( p3, px2 );
+        BOOST_TEST_SP_EQ( px, p2 );
+
+        boost::shared_ptr<X> px4( new X );
+        boost::shared_ptr<X> cmp( px2 );
+
+        bool r = px.atomic_compare_swap( cmp, px4, boost::memory_order_acquire, boost::memory_order_relaxed );
+        BOOST_TEST( !r );
+        BOOST_TEST_SP_EQ( px, p2 );
+        BOOST_TEST_SP_EQ( cmp, p2 );
+
+        r = px.atomic_compare_swap( cmp, px4, boost::memory_order_release, boost::memory_order_acquire );
+        BOOST_TEST( r );
+        BOOST_TEST_SP_EQ( px, px4 );
+    }
+
+    return boost::report_errors();
+}