GCC Code Coverage Report

Directory: ./
File: libs/capy/src/ex/thread_pool.cpp
Date: 2026-01-20 10:35:39
Exec Total Coverage
Lines: 60 68 88.2%
Functions: 14 16 87.5%
Branches: 21 29 72.4%
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/core/intrusive_queue.hpp>
12 #include <condition_variable>
13 #include <mutex>
14 #include <stop_token>
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 : intrusive_queue<work>::node
26 {
27 any_coro h_;
28
29 120 explicit work(any_coro h) noexcept
30 120 : h_(h)
31 {
32 120 }
33
34 120 void run()
35 {
36 120 auto h = h_;
37
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 120 delete this;
38
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 120 h.resume();
39 120 }
40
41 ✗ void destroy()
42 {
43 ✗ delete this;
44 ✗ }
45 };
46
47 std::mutex mutex_;
48 std::condition_variable_any cv_;
49 intrusive_queue<work> q_;
50 std::vector<std::jthread> threads_;
51 std::size_t num_threads_;
52 std::once_flag start_flag_;
53
54 public:
55 49 ~impl()
56 {
57 49 stop();
58 49 threads_.clear();
59
60
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 49 while(auto* w = q_.pop())
61 ✗ w->destroy();
62 49 }
63
64 explicit
65 49 impl(std::size_t num_threads)
66 49 : num_threads_(num_threads)
67 {
68
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 49 if(num_threads_ == 0)
69 1 num_threads_ = std::thread::hardware_concurrency();
70
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 49 if(num_threads_ == 0)
71 ✗ num_threads_ = 1;
72 49 }
73
74 void
75 120 post(any_coro h)
76 {
77 120 ensure_started();
78 120 auto* w = new work(h);
79 {
80
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 120 std::lock_guard<std::mutex> lock(mutex_);
81 120 q_.push(w);
82 120 }
83 120 cv_.notify_one();
84 120 }
85
86 void
87 49 stop() noexcept
88 {
89
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 80 for (auto& t : threads_)
90 31 t.request_stop();
91 49 cv_.notify_all();
92 49 }
93
94 private:
95 void
96 120 ensure_started()
97 {
98
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 120 std::call_once(start_flag_, [this]{
99 19 threads_.reserve(num_threads_);
100
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 50 for(std::size_t i = 0; i < num_threads_; ++i)
101
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 62 threads_.emplace_back([this](std::stop_token st){ run(st); });
102 19 });
103 120 }
104
105 void
106 31 run(std::stop_token st)
107 {
108 for(;;)
109 {
110 151 work* w = nullptr;
111 {
112
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 151 std::unique_lock<std::mutex> lock(mutex_);
113
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 351 if(!cv_.wait(lock, st, [this]{ return !q_.empty(); }))
114 62 return;
115 120 w = q_.pop();
116 151 }
117 120 w->run();
118 120 }
119 }
120 };
121
122 //------------------------------------------------------------------------------
123
124 49 thread_pool::
125 ~thread_pool()
126 {
127 49 shutdown();
128 49 destroy();
129
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 49 delete impl_;
130 49 }
131
132 49 thread_pool::
133 49 thread_pool(std::size_t num_threads)
134
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 49 : impl_(new impl(num_threads))
135 {
136 49 }
137
138 void
139 ✗ thread_pool::
140 stop() noexcept
141 {
142 ✗ impl_->stop();
143 ✗ }
144
145 //------------------------------------------------------------------------------
146
147 void
148 120 thread_pool::executor_type::
149 post(any_coro h) const
150 {
151 120 pool_->impl_->post(h);
152 120 }
153
154 } // capy
155 } // boost
156