GCC Code Coverage Report

Directory: ./
File: libs/capy/src/ex/thread_pool.cpp
Date: 2026-01-21 22:59:20
Exec Total Coverage
Lines: 63 71 88.7%
Functions: 14 16 87.5%
Branches: 29 38 76.3%
Line Branch Exec Source
1 //
2 // Copyright (c) 2025 Vinnie Falco (vinnie.falco@gmail.com)
3 //
4 // Distributed under the Boost Software License, Version 1.0. (See accompanying
5 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
6 //
7 // Official repository: https://github.com/boostorg/capy
8 //
9
10 #include <boost/capy/ex/thread_pool.hpp>
11 #include <boost/capy/detail/intrusive.hpp>
12 #include <atomic>
13 #include <condition_variable>
14 #include <mutex>
15 #include <thread>
16 #include <vector>
17
18 namespace boost {
19 namespace capy {
20
21 //------------------------------------------------------------------------------
22
23 class thread_pool::impl
24 {
25 struct work : detail::intrusive_queue<work>::node
26 {
27 coro h_;
28
29 118 explicit work(coro h) noexcept
30 118 : h_(h)
31 {
32 118 }
33
34 118 void run()
35 {
36 118 auto h = h_;
37
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 118 delete this;
38
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 118 h.resume();
39 118 }
40
41 ✗ void destroy()
42 {
43 ✗ delete this;
44 ✗ }
45 };
46
47 std::mutex mutex_;
48 std::condition_variable_any cv_;
49 detail::intrusive_queue<work> q_;
50 std::vector<std::thread> threads_;
51 std::atomic<bool> stop_requested_{false};
52 std::size_t num_threads_;
53 std::once_flag start_flag_;
54
55 public:
56 51 ~impl()
57 {
58 51 stop();
59
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 82 for (auto& t : threads_)
60
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 31 if (t.joinable())
61 31 t.join();
62 51 threads_.clear();
63
64
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 51 while(auto* w = q_.pop())
65 ✗ w->destroy();
66 51 }
67
68 explicit
69 51 impl(std::size_t num_threads)
70 51 : num_threads_(num_threads)
71 {
72
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 51 if(num_threads_ == 0)
73 1 num_threads_ = std::thread::hardware_concurrency();
74
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 51 if(num_threads_ == 0)
75 ✗ num_threads_ = 1;
76 51 }
77
78 void
79 118 post(coro h)
80 {
81 118 ensure_started();
82 118 auto* w = new work(h);
83 {
84
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 118 std::lock_guard<std::mutex> lock(mutex_);
85 118 q_.push(w);
86 118 }
87 118 cv_.notify_one();
88 118 }
89
90 void
91 51 stop() noexcept
92 {
93 51 stop_requested_.store(true);
94 51 cv_.notify_all();
95 51 }
96
97 private:
98 void
99 118 ensure_started()
100 {
101
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 118 std::call_once(start_flag_, [this]{
102 19 threads_.reserve(num_threads_);
103
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 50 for(std::size_t i = 0; i < num_threads_; ++i)
104
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 62 threads_.emplace_back([this]{ run(); });
105 19 });
106 118 }
107
108 void
109 31 run()
110 {
111 for(;;)
112 {
113 149 work* w = nullptr;
114 {
115
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 149 std::unique_lock<std::mutex> lock(mutex_);
116
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 361 cv_.wait(lock, [this]{ return !q_.empty() || stop_requested_.load(); });
117
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 149 if (stop_requested_.load() && q_.empty())
118 62 return;
119 118 w = q_.pop();
120 149 }
121 118 w->run();
122 118 }
123 }
124 };
125
126 //------------------------------------------------------------------------------
127
128 51 thread_pool::
129 ~thread_pool()
130 {
131 51 shutdown();
132 51 destroy();
133
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 51 delete impl_;
134 51 }
135
136 51 thread_pool::
137 51 thread_pool(std::size_t num_threads)
138
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 51 : impl_(new impl(num_threads))
139 {
140 51 }
141
142 void
143 ✗ thread_pool::
144 stop() noexcept
145 {
146 ✗ impl_->stop();
147 ✗ }
148
149 //------------------------------------------------------------------------------
150
151 void
152 118 thread_pool::executor_type::
153 post(coro h) const
154 {
155 118 pool_->impl_->post(h);
156 118 }
157
158 } // capy
159 } // boost
160