Index/src / corosio / src / io_context.cpp

src/corosio/src/io_context.cpp

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io_context.cpp
f(x) Functions (13)
Function Calls Lines Branches Blocks
boost::corosio::select_t::construct(boost::capy::execution_context&, unsigned int) :74 586x 100.0% – 100.0% boost::corosio::kqueue_t::construct(boost::capy::execution_context&, unsigned int) :92 745x 100.0% – 100.0% boost::corosio::(anonymous namespace)::pre_create_services(boost::capy::execution_context&, boost::corosio::io_context_options const&) :153 25x 87.5% 50.0% 50.0% boost::corosio::(anonymous namespace)::make_threading_config(boost::corosio::io_context_options const&) :176 1331x 100.0% – 100.0% boost::corosio::(anonymous namespace)::apply_scheduler_options(boost::corosio::detail::scheduler&, boost::corosio::io_context_options const&, unsigned int) :190 25x 100.0% 75.0% 91.0% boost::corosio::(anonymous namespace)::construct_default(boost::capy::execution_context&, unsigned int) :247 159x 100.0% – 100.0% boost::corosio::io_context::io_context() :262 150x 100.0% – 100.0% boost::corosio::io_context::io_context(unsigned int) :267 304x 100.0% 50.0% 100.0% boost::corosio::io_context::io_context(boost::corosio::io_context_options const&, unsigned int) :276 14x 100.0% 50.0% 100.0% boost::corosio::io_context::apply_options_pre_(boost::corosio::io_context_options const&) :292 18x 100.0% – 100.0% boost::corosio::io_context::apply_options_post_(boost::corosio::io_context_options const&, unsigned int) :298 18x 100.0% – 100.0% boost::corosio::io_context::apply_threading_(boost::corosio::io_context_options const&) :306 1306x 100.0% – 100.0% boost::corosio::io_context::~io_context() :311 2636x 100.0% – 100.0%
Line Branch TLA Hits Source Code
1 //
2 // Copyright (c) 2026 Steve Gerbino
3 // Copyright (c) 2026 Michael Vandeberg
4 //
5 // Distributed under the Boost Software License, Version 1.0. (See accompanying
6 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
7 //
8 // Official repository: https://github.com/cppalliance/corosio
9 //
10
11 #include <boost/corosio/io_context.hpp>
12 #include <boost/corosio/backend.hpp>
13 #include <boost/corosio/detail/thread_pool.hpp>
14
15 #include <algorithm>
16 #include <stdexcept>
17 #include <thread>
18
19 #if BOOST_COROSIO_HAS_EPOLL
20 #include <boost/corosio/native/detail/epoll/epoll_types.hpp>
21 #endif
22
23 #if BOOST_COROSIO_HAS_SELECT
24 #include <boost/corosio/native/detail/select/select_types.hpp>
25 #endif
26
27 #if BOOST_COROSIO_HAS_KQUEUE
28 #include <boost/corosio/native/detail/kqueue/kqueue_types.hpp>
29 #endif
30
31 #if BOOST_COROSIO_HAS_IO_URING
32 #include <boost/corosio/native/detail/io_uring/io_uring_acceptor_ops.hpp>
33 #include <boost/corosio/native/detail/io_uring/io_uring_buffer.hpp>
34 #include <boost/corosio/native/detail/io_uring/io_uring_dgram_ops.hpp>
35 #include <boost/corosio/native/detail/io_uring/io_uring_multishot_acceptor.hpp>
36 #include <boost/corosio/native/detail/io_uring/io_uring_random_access_file.hpp>
37 #include <boost/corosio/native/detail/io_uring/io_uring_scheduler.hpp>
38 #include <boost/corosio/native/detail/io_uring/io_uring_stream_file.hpp>
39 #include <boost/corosio/native/detail/io_uring/io_uring_types.hpp>
40 #endif
41
42 #if BOOST_COROSIO_HAS_IOCP
43 #include <boost/corosio/native/detail/iocp/win_scheduler.hpp>
44 #include <boost/corosio/native/detail/iocp/win_tcp_acceptor_service.hpp>
45 #include <boost/corosio/native/detail/iocp/win_udp_service.hpp>
46 #include <boost/corosio/native/detail/iocp/win_local_stream_acceptor_service.hpp>
47 #include <boost/corosio/native/detail/iocp/win_signals.hpp>
48 #include <boost/corosio/native/detail/iocp/win_file_service.hpp>
49 #include <boost/corosio/native/detail/iocp/win_random_access_file_service.hpp>
50 #endif
51
52 namespace boost::corosio {
53
54 #if BOOST_COROSIO_HAS_EPOLL
55 detail::scheduler&
56 epoll_t::construct(capy::execution_context& ctx, unsigned concurrency_hint)
57 {
58 auto& sched = ctx.make_service<detail::epoll_scheduler>(
59 static_cast<int>(concurrency_hint));
60
61 ctx.make_service<detail::epoll_tcp_service>();
62 ctx.make_service<detail::epoll_tcp_acceptor_service>();
63 ctx.make_service<detail::epoll_udp_service>();
64 ctx.make_service<detail::epoll_local_stream_service>();
65 ctx.make_service<detail::epoll_local_stream_acceptor_service>();
66 ctx.make_service<detail::epoll_local_datagram_service>();
67
68 return sched;
69 }
70 #endif
71
72 #if BOOST_COROSIO_HAS_SELECT
73 detail::scheduler&
74 586x select_t::construct(capy::execution_context& ctx, unsigned concurrency_hint)
75 {
76 1172x auto& sched = ctx.make_service<detail::select_scheduler>(
77 586x static_cast<int>(concurrency_hint));
78
79 586x ctx.make_service<detail::select_tcp_service>();
80 586x ctx.make_service<detail::select_tcp_acceptor_service>();
81 586x ctx.make_service<detail::select_udp_service>();
82 586x ctx.make_service<detail::select_local_stream_service>();
83 586x ctx.make_service<detail::select_local_stream_acceptor_service>();
84 586x ctx.make_service<detail::select_local_datagram_service>();
85
86 586x return sched;
87 }
88 #endif
89
90 #if BOOST_COROSIO_HAS_KQUEUE
91 detail::scheduler&
92 745x kqueue_t::construct(capy::execution_context& ctx, unsigned concurrency_hint)
93 {
94 1490x auto& sched = ctx.make_service<detail::kqueue_scheduler>(
95 745x static_cast<int>(concurrency_hint));
96
97 745x ctx.make_service<detail::kqueue_tcp_service>();
98 745x ctx.make_service<detail::kqueue_tcp_acceptor_service>();
99 745x ctx.make_service<detail::kqueue_udp_service>();
100 745x ctx.make_service<detail::kqueue_local_stream_service>();
101 745x ctx.make_service<detail::kqueue_local_stream_acceptor_service>();
102 745x ctx.make_service<detail::kqueue_local_datagram_service>();
103
104 745x return sched;
105 }
106 #endif
107
108 #if BOOST_COROSIO_HAS_IOCP
109 detail::scheduler&
110 iocp_t::construct(capy::execution_context& ctx, unsigned concurrency_hint)
111 {
112 auto& sched = ctx.make_service<detail::win_scheduler>(
113 static_cast<int>(concurrency_hint));
114
115 auto& tcp_svc = ctx.make_service<detail::win_tcp_service>();
116 ctx.make_service<detail::win_tcp_acceptor_service>(tcp_svc);
117 ctx.make_service<detail::win_udp_service>();
118 auto& local_svc =
119 ctx.make_service<detail::win_local_stream_service>(tcp_svc);
120 ctx.make_service<detail::win_local_stream_acceptor_service>(local_svc);
121 ctx.make_service<detail::win_signals>();
122 ctx.make_service<detail::win_file_service>();
123 ctx.make_service<detail::win_random_access_file_service>();
124
125 return sched;
126 }
127 #endif
128
129 #if BOOST_COROSIO_HAS_IO_URING
130 detail::scheduler&
131 io_uring_t::construct(capy::execution_context& ctx, unsigned concurrency_hint)
132 {
133 auto& sched = ctx.make_service<detail::io_uring_scheduler>(
134 static_cast<int>(concurrency_hint));
135
136 ctx.make_service<detail::io_uring_tcp_service>();
137 ctx.make_service<detail::io_uring_tcp_acceptor_service>();
138 ctx.make_service<detail::io_uring_local_stream_service>();
139 ctx.make_service<detail::io_uring_local_stream_acceptor_service>();
140 ctx.make_service<detail::io_uring_udp_service>();
141 ctx.make_service<detail::io_uring_local_datagram_service>();
142 ctx.make_service<detail::io_uring_stream_file_service>(sched);
143 ctx.make_service<detail::io_uring_random_access_file_service>(sched);
144
145 return sched;
146 }
147 #endif
148
149 namespace {
150
151 // Pre-create services that must exist before construct() runs.
152 void
153 25x pre_create_services(
154 capy::execution_context& ctx,
155 io_context_options const& opts)
156 {
157 #if BOOST_COROSIO_POSIX
158
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 25x if (opts.thread_pool_size < 1)
159 ✗ throw std::invalid_argument(
160 "thread_pool_size must be at least 1");
161 // Pre-create the shared thread pool with the configured size.
162 // This must happen before construct() because the scheduler
163 // constructor creates file and resolver services that call
164 // get_or_create_pool(), which would create a 1-thread pool.
165
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 25x if (opts.thread_pool_size != 1)
166 2x ctx.make_service<detail::thread_pool>(opts.thread_pool_size);
167 #endif
168
169 25x (void)ctx;
170 25x (void)opts;
171 25x }
172
173 // Map the locking tier to the scheduler's threading facilities. one_thread is
174 // set only for the lockless tiers, where a single run thread is guaranteed.
175 detail::scheduler::threading_config
176 1331x make_threading_config(io_context_options const& opts)
177 {
178 1331x detail::scheduler::threading_config cfg;
179 1331x cfg.scheduler_locking = opts.locking != locking_mode::unsafe;
180 1331x cfg.reactor_io_locking = opts.locking == locking_mode::safe;
181 1331x cfg.one_thread = opts.locking != locking_mode::safe;
182 1331x return cfg;
183 }
184
185 // Apply runtime tuning after construction. `concurrency_hint` is the effective
186 // hint (normalized to 1 for lockless tiers). Budget heuristic: with default
187 // budgets and hint > 1, disable the inline-completion fast path so multi-thread
188 // runs post everything for cross-thread work-stealing.
189 void
190 25x apply_scheduler_options(
191 detail::scheduler& sched,
192 io_context_options const& opts,
193 unsigned concurrency_hint)
194 {
195 25x sched.configure_threading(make_threading_config(opts));
196
197 #if BOOST_COROSIO_HAS_EPOLL || BOOST_COROSIO_HAS_KQUEUE || BOOST_COROSIO_HAS_SELECT
198 // dynamic_cast — when io_uring is also linked, the runtime probe may
199 // have selected io_uring_scheduler instead of a reactor_scheduler.
200
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 25x if (auto* reactor =
201
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 25x dynamic_cast<detail::reactor_scheduler*>(&sched))
202 {
203 // Detect "user kept the defaults" by comparing all three to the
204 // io_context-options-defined struct defaults.
205 25x io_context_options defaults;
206 25x bool budget_at_defaults =
207
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 25x opts.inline_budget_initial == defaults.inline_budget_initial &&
208
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 15x opts.inline_budget_max == defaults.inline_budget_max &&
209 15x opts.unassisted_budget == defaults.unassisted_budget;
210
211 25x unsigned init = opts.inline_budget_initial;
212 25x unsigned max = opts.inline_budget_max;
213 25x unsigned ua = opts.unassisted_budget;
214
215
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 25x if (budget_at_defaults && concurrency_hint > 1)
216 {
217 // Multi-thread default: disable budget (post-everything).
218 4x init = 0;
219 4x max = 0;
220 4x ua = 0;
221 4x }
222
223 50x reactor->configure_reactor(
224 25x opts.max_events_per_poll,
225 25x init,
226 25x max,
227 25x ua);
228 25x }
229 #endif
230
231 #if BOOST_COROSIO_HAS_IO_URING
232 if (auto* uring_sched =
233 dynamic_cast<detail::io_uring_scheduler*>(&sched))
234 {
235 if (opts.enable_sqpoll)
236 uring_sched->configure_sqpoll(
237 true, opts.sq_thread_idle_ms, opts.sq_thread_cpu);
238 }
239 #endif
240
241 25x (void)sched;
242 25x (void)opts;
243 (void)concurrency_hint;
244 25x }
245
246 detail::scheduler&
247 159x construct_default(capy::execution_context& ctx, unsigned concurrency_hint)
248 {
249 #if BOOST_COROSIO_HAS_IOCP
250 return iocp_t::construct(ctx, concurrency_hint);
251 #elif BOOST_COROSIO_HAS_EPOLL
252 return epoll_t::construct(ctx, concurrency_hint);
253 #elif BOOST_COROSIO_HAS_KQUEUE
254 159x return kqueue_t::construct(ctx, concurrency_hint);
255 #elif BOOST_COROSIO_HAS_SELECT
256 return select_t::construct(ctx, concurrency_hint);
257 #endif
258 }
259
260 } // anonymous namespace
261
262 150x io_context::io_context()
263 150x : io_context(std::max(1u, std::thread::hardware_concurrency()))
264 {
265 150x }
266
267 304x io_context::io_context(unsigned concurrency_hint)
268 152x : capy::execution_context(this)
269
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 152x , sched_(&construct_default(*this, concurrency_hint))
270 152x {
271 // Threading config only; the plain path leaves the reactor budget at its
272 // defaults (no options-ctor budget heuristic).
273
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 152x apply_threading_(io_context_options{});
274 304x }
275
276 14x io_context::io_context(
277 io_context_options const& opts_in,
278 unsigned concurrency_hint)
279 7x : capy::execution_context(this)
280 7x , sched_(nullptr)
281 7x {
282
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 7x pre_create_services(*this, opts_in);
283 // Computed before construct_default so IOCP's completion port is created
284 // with the effective concurrency.
285 7x unsigned const eff =
286 7x detail::effective_concurrency_hint(opts_in, concurrency_hint);
287
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 7x sched_ = &construct_default(*this, eff);
288
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 7x apply_scheduler_options(*sched_, opts_in, eff);
289 14x }
290
291 void
292 18x io_context::apply_options_pre_(io_context_options const& opts)
293 {
294 18x pre_create_services(*this, opts);
295 18x }
296
297 void
298 18x io_context::apply_options_post_(
299 io_context_options const& opts_in,
300 unsigned concurrency_hint)
301 {
302 18x apply_scheduler_options(*sched_, opts_in, concurrency_hint);
303 18x }
304
305 void
306 1306x io_context::apply_threading_(io_context_options const& opts_in)
307 {
308 1306x sched_->configure_threading(make_threading_config(opts_in));
309 1306x }
310
311 2636x io_context::~io_context()
312 1307x {
313 1329x shutdown();
314 1329x destroy();
315 2636x }
316
317 } // namespace boost::corosio
318