Quickbook: Merge from trunk.

[SVN r77380]

example/shared_monitor.cpp

@@ -0,0 +1,136 @@
+// Copyright (C) 2012 Vicente J. Botet Escriba
+//
+//  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 <iostream>
+#include <boost/thread/mutex.hpp>
+#include <boost/thread/shared_mutex.hpp>
+#include <boost/thread/thread.hpp>
+#include <boost/chrono/chrono_io.hpp>
+
+#include <cassert>
+#include <vector>
+
+#define EXCLUSIVE 1
+#define SHARED 2
+
+#define MODE SHARED
+
+class A
+{
+#if MODE == EXCLUSIVE
+    typedef boost::mutex mutex_type;
+#elif MODE == SHARED
+    typedef boost::shared_mutex mutex_type;
+#else
+#error MODE not set
+#endif
+    typedef std::vector<double> C;
+    mutable mutex_type mut_;
+    C data_;
+public:
+    A() : data_(10000000) {}
+    A(const A& a);
+    A& operator=(const A& a);
+
+    void compute(const A& x, const A& y);
+};
+
+A::A(const A& a)
+{
+#if MODE == EXCLUSIVE
+    boost::unique_lock<mutex_type> lk(a.mut_);
+#elif MODE == SHARED
+    boost::shared_lock<mutex_type> lk(a.mut_);
+#else
+#error MODE not set
+#endif
+    data_ = a.data_;
+}
+
+A&
+A::operator=(const A& a)
+{
+    if (this != &a)
+    {
+        boost::unique_lock<mutex_type> lk1(mut_, boost::defer_lock);
+#if MODE == EXCLUSIVE
+        boost::unique_lock<mutex_type> lk2(a.mut_, boost::defer_lock);
+#elif MODE == SHARED
+        boost::shared_lock<mutex_type> lk2(a.mut_, boost::defer_lock);
+#else
+#error MODE not set
+#endif
+        boost::lock(lk1, lk2);
+        data_ = a.data_;
+    }
+    return *this;
+}
+
+void
+A::compute(const A& x, const A& y)
+{
+    boost::unique_lock<mutex_type> lk1(mut_, boost::defer_lock);
+#if MODE == EXCLUSIVE
+    boost::unique_lock<mutex_type> lk2(x.mut_, boost::defer_lock);
+    boost::unique_lock<mutex_type> lk3(y.mut_, boost::defer_lock);
+#elif MODE == SHARED
+    boost::shared_lock<mutex_type> lk2(x.mut_, boost::defer_lock);
+    boost::shared_lock<mutex_type> lk3(y.mut_, boost::defer_lock);
+#else
+#error MODE not set
+#endif
+    boost::lock(lk1, lk2, lk3);
+    assert(data_.size() == x.data_.size());
+    assert(data_.size() == y.data_.size());
+    for (unsigned i = 0; i < data_.size(); ++i)
+        data_[i] = (x.data_[i] + y.data_[i]) / 2;
+}
+
+A a1;
+A a2;
+
+void test_s()
+{
+    A la3 = a1;
+    for (int i = 0; i < 150; ++i)
+    {
+        la3.compute(a1, a2);
+    }
+}
+
+void test_w()
+{
+    A la3 = a1;
+    for (int i = 0; i < 10; ++i)
+    {
+        la3.compute(a1, a2);
+        a1 = la3;
+        a2 = la3;
+//        boost::this_thread::sleep_for(boost::chrono::seconds(1));
+    }
+}
+
+int main()
+{
+    typedef boost::chrono::high_resolution_clock Clock;
+    typedef boost::chrono::duration<double> sec;
+    Clock::time_point t0 = Clock::now();
+    std::vector<boost::thread*> v;
+    boost::thread thw(test_w);
+    v.push_back(&thw);
+    boost::thread thr0(test_w);
+    v.push_back(&thr0);
+    boost::thread thr1(test_w);
+    v.push_back(&thr1);
+    boost::thread thr2(test_w);
+    v.push_back(&thr2);
+    boost::thread thr3(test_w);
+    v.push_back(&thr3);
+    for (int i = 0; i < v.size(); ++i)
+        v[i]->join();
+    Clock::time_point t1 = Clock::now();
+    std::cout << sec(t1-t0) << '\n';
+    return 0;
+}