1 | // Copyright (C) 2012 Vicente J. Botet Escriba |
2 | // |
3 | // Distributed under the Boost Software License, Version 1.0. (See accompanying |
4 | // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) |
5 | |
6 | #include <iostream> |
7 | #include <boost/thread/mutex.hpp> |
8 | #include <boost/thread/shared_mutex.hpp> |
9 | #include <boost/thread/lock_algorithms.hpp> |
10 | #include <boost/thread/thread_only.hpp> |
11 | #if defined BOOST_THREAD_DONT_USE_CHRONO |
12 | #include <boost/chrono/chrono_io.hpp> |
13 | #endif |
14 | #include <cassert> |
15 | #include <vector> |
16 | |
17 | #define EXCLUSIVE 1 |
18 | #define SHARED 2 |
19 | |
20 | #define MODE SHARED |
21 | |
22 | class A |
23 | { |
24 | #if MODE == EXCLUSIVE |
25 | typedef boost::mutex mutex_type; |
26 | #elif MODE == SHARED |
27 | typedef boost::shared_mutex mutex_type; |
28 | #else |
29 | #error MODE not set |
30 | #endif |
31 | typedef std::vector<double> C; |
32 | mutable mutex_type mut_; |
33 | C data_; |
34 | public: |
35 | A() : data_(10000000) {} |
36 | A(const A& a); |
37 | A& operator=(const A& a); |
38 | |
39 | void compute(const A& x, const A& y); |
40 | }; |
41 | |
42 | A::A(const A& a) |
43 | { |
44 | #if MODE == EXCLUSIVE |
45 | boost::unique_lock<mutex_type> lk(a.mut_); |
46 | #elif MODE == SHARED |
47 | boost::shared_lock<mutex_type> lk(a.mut_); |
48 | #else |
49 | #error MODE not set |
50 | #endif |
51 | data_ = a.data_; |
52 | } |
53 | |
54 | A& |
55 | A::operator=(const A& a) |
56 | { |
57 | if (this != &a) |
58 | { |
59 | boost::unique_lock<mutex_type> lk1(mut_, boost::defer_lock); |
60 | #if MODE == EXCLUSIVE |
61 | boost::unique_lock<mutex_type> lk2(a.mut_, boost::defer_lock); |
62 | #elif MODE == SHARED |
63 | boost::shared_lock<mutex_type> lk2(a.mut_, boost::defer_lock); |
64 | #else |
65 | #error MODE not set |
66 | #endif |
67 | boost::lock(m1&: lk1, m2&: lk2); |
68 | data_ = a.data_; |
69 | } |
70 | return *this; |
71 | } |
72 | |
73 | void |
74 | A::compute(const A& x, const A& y) |
75 | { |
76 | boost::unique_lock<mutex_type> lk1(mut_, boost::defer_lock); |
77 | #if MODE == EXCLUSIVE |
78 | boost::unique_lock<mutex_type> lk2(x.mut_, boost::defer_lock); |
79 | boost::unique_lock<mutex_type> lk3(y.mut_, boost::defer_lock); |
80 | #elif MODE == SHARED |
81 | boost::shared_lock<mutex_type> lk2(x.mut_, boost::defer_lock); |
82 | boost::shared_lock<mutex_type> lk3(y.mut_, boost::defer_lock); |
83 | #else |
84 | #error MODE not set |
85 | #endif |
86 | boost::lock(m1&: lk1, m2&: lk2, m3&: lk3); |
87 | assert(data_.size() == x.data_.size()); |
88 | assert(data_.size() == y.data_.size()); |
89 | for (unsigned i = 0; i < data_.size(); ++i) |
90 | data_[i] = (x.data_[i] + y.data_[i]) / 2; |
91 | } |
92 | |
93 | A a1; |
94 | A a2; |
95 | |
96 | void test_s() |
97 | { |
98 | A la3 = a1; |
99 | for (int i = 0; i < 150; ++i) |
100 | { |
101 | la3.compute(x: a1, y: a2); |
102 | } |
103 | } |
104 | |
105 | void test_w() |
106 | { |
107 | A la3 = a1; |
108 | for (int i = 0; i < 10; ++i) |
109 | { |
110 | la3.compute(x: a1, y: a2); |
111 | a1 = la3; |
112 | a2 = la3; |
113 | #if defined BOOST_THREAD_DONT_USE_CHRONO |
114 | boost::this_thread::sleep_for(boost::chrono::seconds(1)); |
115 | #endif |
116 | } |
117 | } |
118 | |
119 | int main() |
120 | { |
121 | #if defined BOOST_THREAD_DONT_USE_CHRONO |
122 | typedef boost::chrono::high_resolution_clock Clock; |
123 | typedef boost::chrono::duration<double> sec; |
124 | Clock::time_point t0 = Clock::now(); |
125 | #endif |
126 | std::vector<boost::thread*> v; |
127 | boost::thread thw(test_w); |
128 | v.push_back(x: &thw); |
129 | boost::thread thr0(test_w); |
130 | v.push_back(x: &thr0); |
131 | boost::thread thr1(test_w); |
132 | v.push_back(x: &thr1); |
133 | boost::thread thr2(test_w); |
134 | v.push_back(x: &thr2); |
135 | boost::thread thr3(test_w); |
136 | v.push_back(x: &thr3); |
137 | for (std::size_t i = 0; i < v.size(); ++i) |
138 | v[i]->join(); |
139 | #if defined BOOST_THREAD_DONT_USE_CHRONO |
140 | Clock::time_point t1 = Clock::now(); |
141 | std::cout << sec(t1-t0) << '\n'; |
142 | #endif |
143 | return 0; |
144 | } |
145 | |