smart_ptr/extras/test/sp_atomic_mt_test.cpp

192 lines
3.4 KiB
C++

// 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 = boost::atomic_load( &ps );
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();
boost::atomic_store( &ps, 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();
boost::detail::lw_thread_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 )
{
boost::detail::lw_thread_join( a[ j ] );
}
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();
}