. /include/boost/corosio /native /detail /epoll /epoll_scheduler.hpp
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1   // 1   //
2   // Copyright (c) 2026 Steve Gerbino 2   // Copyright (c) 2026 Steve Gerbino
3   // 3   //
4   // Distributed under the Boost Software License, Version 1.0. (See accompanying 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) 5   // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
6   // 6   //
7   // Official repository: https://github.com/cppalliance/corosio 7   // Official repository: https://github.com/cppalliance/corosio
8   // 8   //
9   9  
10   #ifndef BOOST_COROSIO_NATIVE_DETAIL_EPOLL_EPOLL_SCHEDULER_HPP 10   #ifndef BOOST_COROSIO_NATIVE_DETAIL_EPOLL_EPOLL_SCHEDULER_HPP
11   #define BOOST_COROSIO_NATIVE_DETAIL_EPOLL_EPOLL_SCHEDULER_HPP 11   #define BOOST_COROSIO_NATIVE_DETAIL_EPOLL_EPOLL_SCHEDULER_HPP
12   12  
13   #include <boost/corosio/detail/platform.hpp> 13   #include <boost/corosio/detail/platform.hpp>
14   14  
15   #if BOOST_COROSIO_HAS_EPOLL 15   #if BOOST_COROSIO_HAS_EPOLL
16   16  
17   #include <boost/corosio/detail/config.hpp> 17   #include <boost/corosio/detail/config.hpp>
18   #include <boost/capy/ex/execution_context.hpp> 18   #include <boost/capy/ex/execution_context.hpp>
19   19  
20   #include <boost/corosio/native/detail/reactor/reactor_scheduler.hpp> 20   #include <boost/corosio/native/detail/reactor/reactor_scheduler.hpp>
21   21  
22   #include <boost/corosio/native/detail/epoll/epoll_traits.hpp> 22   #include <boost/corosio/native/detail/epoll/epoll_traits.hpp>
23   #include <boost/corosio/detail/timer_service.hpp> 23   #include <boost/corosio/detail/timer_service.hpp>
24   #include <boost/corosio/native/detail/make_err.hpp> 24   #include <boost/corosio/native/detail/make_err.hpp>
25   #include <boost/corosio/native/detail/posix/posix_resolver_service.hpp> 25   #include <boost/corosio/native/detail/posix/posix_resolver_service.hpp>
26   #include <boost/corosio/native/detail/posix/posix_signal_service.hpp> 26   #include <boost/corosio/native/detail/posix/posix_signal_service.hpp>
27   #include <boost/corosio/native/detail/posix/posix_stream_file_service.hpp> 27   #include <boost/corosio/native/detail/posix/posix_stream_file_service.hpp>
28   #include <boost/corosio/native/detail/posix/posix_random_access_file_service.hpp> 28   #include <boost/corosio/native/detail/posix/posix_random_access_file_service.hpp>
29   29  
30   #include <boost/corosio/detail/except.hpp> 30   #include <boost/corosio/detail/except.hpp>
31   31  
32   #include <atomic> 32   #include <atomic>
33   #include <chrono> 33   #include <chrono>
34   #include <cstdint> 34   #include <cstdint>
35   #include <mutex> 35   #include <mutex>
36   #include <vector> 36   #include <vector>
37   37  
38   #include <errno.h> 38   #include <errno.h>
39   #include <sys/epoll.h> 39   #include <sys/epoll.h>
40   #include <sys/eventfd.h> 40   #include <sys/eventfd.h>
41   #include <sys/timerfd.h> 41   #include <sys/timerfd.h>
42   #include <unistd.h> 42   #include <unistd.h>
43   43  
44   namespace boost::corosio::detail { 44   namespace boost::corosio::detail {
45   45  
46   /** Linux scheduler using epoll for I/O multiplexing. 46   /** Linux scheduler using epoll for I/O multiplexing.
47   47  
48   This scheduler implements the scheduler interface using Linux epoll 48   This scheduler implements the scheduler interface using Linux epoll
49   for efficient I/O event notification. It uses a single reactor model 49   for efficient I/O event notification. It uses a single reactor model
50   where one thread runs epoll_wait while other threads 50   where one thread runs epoll_wait while other threads
51   wait on a condition variable for handler work. This design provides: 51   wait on a condition variable for handler work. This design provides:
52   52  
53   - Handler parallelism: N posted handlers can execute on N threads 53   - Handler parallelism: N posted handlers can execute on N threads
54   - No thundering herd: condition_variable wakes exactly one thread 54   - No thundering herd: condition_variable wakes exactly one thread
55   - IOCP parity: Behavior matches Windows I/O completion port semantics 55   - IOCP parity: Behavior matches Windows I/O completion port semantics
56   56  
57   When threads call run(), they first try to execute queued handlers. 57   When threads call run(), they first try to execute queued handlers.
58   If the queue is empty and no reactor is running, one thread becomes 58   If the queue is empty and no reactor is running, one thread becomes
59   the reactor and runs epoll_wait. Other threads wait on a condition 59   the reactor and runs epoll_wait. Other threads wait on a condition
60   variable until handlers are available. 60   variable until handlers are available.
61   61  
62   @par Thread Safety 62   @par Thread Safety
63   All public member functions are thread-safe. 63   All public member functions are thread-safe.
64   */ 64   */
65   class BOOST_COROSIO_DECL epoll_scheduler final : public reactor_scheduler 65   class BOOST_COROSIO_DECL epoll_scheduler final : public reactor_scheduler
66   { 66   {
67   public: 67   public:
68   /** Construct the scheduler. 68   /** Construct the scheduler.
69   69  
70   Creates an epoll instance, eventfd for reactor interruption, 70   Creates an epoll instance, eventfd for reactor interruption,
71   and timerfd for kernel-managed timer expiry. 71   and timerfd for kernel-managed timer expiry.
72   72  
73   @param ctx Reference to the owning execution_context. 73   @param ctx Reference to the owning execution_context.
74   @param concurrency_hint Hint for expected thread count (unused). 74   @param concurrency_hint Hint for expected thread count (unused).
75   */ 75   */
76   epoll_scheduler(capy::execution_context& ctx, int concurrency_hint = -1); 76   epoll_scheduler(capy::execution_context& ctx, int concurrency_hint = -1);
77   77  
78   /// Destroy the scheduler. 78   /// Destroy the scheduler.
79   ~epoll_scheduler() override; 79   ~epoll_scheduler() override;
80   80  
81   epoll_scheduler(epoll_scheduler const&) = delete; 81   epoll_scheduler(epoll_scheduler const&) = delete;
82   epoll_scheduler& operator=(epoll_scheduler const&) = delete; 82   epoll_scheduler& operator=(epoll_scheduler const&) = delete;
83   83  
84   /// Shut down the scheduler, draining pending operations. 84   /// Shut down the scheduler, draining pending operations.
85   void shutdown() override; 85   void shutdown() override;
86   86  
87   /// Apply runtime configuration, resizing the event buffer. 87   /// Apply runtime configuration, resizing the event buffer.
88   void configure_reactor( 88   void configure_reactor(
89   unsigned max_events, 89   unsigned max_events,
90   unsigned budget_init, 90   unsigned budget_init,
91   unsigned budget_max, 91   unsigned budget_max,
92   unsigned unassisted) override; 92   unsigned unassisted) override;
93   93  
94   /** Return the epoll file descriptor. 94   /** Return the epoll file descriptor.
95   95  
96   Used by socket services to register file descriptors 96   Used by socket services to register file descriptors
97   for I/O event notification. 97   for I/O event notification.
98   98  
99   @return The epoll file descriptor. 99   @return The epoll file descriptor.
100   */ 100   */
101   int epoll_fd() const noexcept 101   int epoll_fd() const noexcept
102   { 102   {
103   return epoll_fd_; 103   return epoll_fd_;
104   } 104   }
105   105  
106   /** Register a descriptor for persistent monitoring. 106   /** Register a descriptor for persistent monitoring.
107   107  
108   The fd is registered once and stays registered until explicitly 108   The fd is registered once and stays registered until explicitly
109   deregistered. Events are dispatched via reactor_descriptor_state which 109   deregistered. Events are dispatched via reactor_descriptor_state which
110   tracks pending read/write/connect operations. 110   tracks pending read/write/connect operations.
111   111  
112   @param fd The file descriptor to register. 112   @param fd The file descriptor to register.
113   @param desc Pointer to descriptor data (stored in epoll_event.data.ptr). 113   @param desc Pointer to descriptor data (stored in epoll_event.data.ptr).
114   */ 114   */
115   void register_descriptor(int fd, reactor_descriptor_state* desc) const; 115   void register_descriptor(int fd, reactor_descriptor_state* desc) const;
116   116  
117   /** Deregister a persistently registered descriptor. 117   /** Deregister a persistently registered descriptor.
118   118  
119   @param fd The file descriptor to deregister. 119   @param fd The file descriptor to deregister.
120   */ 120   */
121   void deregister_descriptor(int fd) const; 121   void deregister_descriptor(int fd) const;
122   122  
123   private: 123   private:
124   void 124   void
125   run_task(lock_type& lock, context_type* ctx, 125   run_task(lock_type& lock, context_type* ctx,
126   long timeout_us) override; 126   long timeout_us) override;
127   void interrupt_reactor() const override; 127   void interrupt_reactor() const override;
128   void update_timerfd() const; 128   void update_timerfd() const;
129   129  
130   int epoll_fd_; 130   int epoll_fd_;
131   int event_fd_; 131   int event_fd_;
132   int timer_fd_; 132   int timer_fd_;
133   133  
134   // Edge-triggered eventfd state 134   // Edge-triggered eventfd state
135   mutable std::atomic<bool> eventfd_armed_{false}; 135   mutable std::atomic<bool> eventfd_armed_{false};
136   136  
137   // Set when the earliest timer changes; flushed before epoll_wait 137   // Set when the earliest timer changes; flushed before epoll_wait
138   mutable std::atomic<bool> timerfd_stale_{false}; 138   mutable std::atomic<bool> timerfd_stale_{false};
139   139  
140   // Event buffer sized from max_events_per_poll_ (set at construction, 140   // Event buffer sized from max_events_per_poll_ (set at construction,
141   // resized by configure_reactor via io_context_options). 141   // resized by configure_reactor via io_context_options).
142   std::vector<epoll_event> event_buffer_; 142   std::vector<epoll_event> event_buffer_;
143   }; 143   };
144   144  
HITCBC 145   593 inline epoll_scheduler::epoll_scheduler(capy::execution_context& ctx, int) 145   593 inline epoll_scheduler::epoll_scheduler(capy::execution_context& ctx, int)
HITCBC 146   593 : epoll_fd_(-1) 146   593 : epoll_fd_(-1)
HITCBC 147   593 , event_fd_(-1) 147   593 , event_fd_(-1)
HITCBC 148   593 , timer_fd_(-1) 148   593 , timer_fd_(-1)
HITCBC 149   1186 , event_buffer_(max_events_per_poll_) 149   1186 , event_buffer_(max_events_per_poll_)
150   { 150   {
HITCBC 151   593 epoll_fd_ = ::epoll_create1(EPOLL_CLOEXEC); 151   593 epoll_fd_ = ::epoll_create1(EPOLL_CLOEXEC);
HITCBC 152   593 if (epoll_fd_ < 0) 152   593 if (epoll_fd_ < 0)
MISUBC 153   ✗ detail::throw_system_error(make_err(errno), "epoll_create1"); 153   ✗ detail::throw_system_error(make_err(errno), "epoll_create1");
154   154  
HITCBC 155   593 event_fd_ = ::eventfd(0, EFD_NONBLOCK | EFD_CLOEXEC); 155   593 event_fd_ = ::eventfd(0, EFD_NONBLOCK | EFD_CLOEXEC);
HITCBC 156   593 if (event_fd_ < 0) 156   593 if (event_fd_ < 0)
157   { 157   {
MISUBC 158   ✗ int errn = errno; 158   ✗ int errn = errno;
MISUBC 159   ✗ ::close(epoll_fd_); 159   ✗ ::close(epoll_fd_);
MISUBC 160   ✗ detail::throw_system_error(make_err(errn), "eventfd"); 160   ✗ detail::throw_system_error(make_err(errn), "eventfd");
161   } 161   }
162   162  
HITCBC 163   593 timer_fd_ = ::timerfd_create(CLOCK_MONOTONIC, TFD_NONBLOCK | TFD_CLOEXEC); 163   593 timer_fd_ = ::timerfd_create(CLOCK_MONOTONIC, TFD_NONBLOCK | TFD_CLOEXEC);
HITCBC 164   593 if (timer_fd_ < 0) 164   593 if (timer_fd_ < 0)
165   { 165   {
MISUBC 166   ✗ int errn = errno; 166   ✗ int errn = errno;
MISUBC 167   ✗ ::close(event_fd_); 167   ✗ ::close(event_fd_);
MISUBC 168   ✗ ::close(epoll_fd_); 168   ✗ ::close(epoll_fd_);
MISUBC 169   ✗ detail::throw_system_error(make_err(errn), "timerfd_create"); 169   ✗ detail::throw_system_error(make_err(errn), "timerfd_create");
170   } 170   }
171   171  
HITCBC 172   593 epoll_event ev{}; 172   593 epoll_event ev{};
HITCBC 173   593 ev.events = EPOLLIN | EPOLLET; 173   593 ev.events = EPOLLIN | EPOLLET;
HITCBC 174   593 ev.data.ptr = nullptr; 174   593 ev.data.ptr = nullptr;
HITCBC 175   593 if (::epoll_ctl(epoll_fd_, EPOLL_CTL_ADD, event_fd_, &ev) < 0) 175   593 if (::epoll_ctl(epoll_fd_, EPOLL_CTL_ADD, event_fd_, &ev) < 0)
176   { 176   {
MISUBC 177   ✗ int errn = errno; 177   ✗ int errn = errno;
MISUBC 178   ✗ ::close(timer_fd_); 178   ✗ ::close(timer_fd_);
MISUBC 179   ✗ ::close(event_fd_); 179   ✗ ::close(event_fd_);
MISUBC 180   ✗ ::close(epoll_fd_); 180   ✗ ::close(epoll_fd_);
MISUBC 181   ✗ detail::throw_system_error(make_err(errn), "epoll_ctl"); 181   ✗ detail::throw_system_error(make_err(errn), "epoll_ctl");
182   } 182   }
183   183  
HITCBC 184   593 epoll_event timer_ev{}; 184   593 epoll_event timer_ev{};
HITCBC 185   593 timer_ev.events = EPOLLIN | EPOLLERR; 185   593 timer_ev.events = EPOLLIN | EPOLLERR;
HITCBC 186   593 timer_ev.data.ptr = &timer_fd_; 186   593 timer_ev.data.ptr = &timer_fd_;
HITCBC 187   593 if (::epoll_ctl(epoll_fd_, EPOLL_CTL_ADD, timer_fd_, &timer_ev) < 0) 187   593 if (::epoll_ctl(epoll_fd_, EPOLL_CTL_ADD, timer_fd_, &timer_ev) < 0)
188   { 188   {
MISUBC 189   ✗ int errn = errno; 189   ✗ int errn = errno;
MISUBC 190   ✗ ::close(timer_fd_); 190   ✗ ::close(timer_fd_);
MISUBC 191   ✗ ::close(event_fd_); 191   ✗ ::close(event_fd_);
MISUBC 192   ✗ ::close(epoll_fd_); 192   ✗ ::close(epoll_fd_);
MISUBC 193   ✗ detail::throw_system_error(make_err(errn), "epoll_ctl (timerfd)"); 193   ✗ detail::throw_system_error(make_err(errn), "epoll_ctl (timerfd)");
194   } 194   }
195   195  
HITCBC 196   593 timer_svc_ = &get_timer_service(ctx, *this); 196   593 timer_svc_ = &get_timer_service(ctx, *this);
HITCBC 197   593 timer_svc_->set_on_earliest_changed( 197   593 timer_svc_->set_on_earliest_changed(
HITCBC 198   5402 timer_service::callback(this, [](void* p) { 198   5281 timer_service::callback(this, [](void* p) {
HITCBC 199   4809 auto* self = static_cast<epoll_scheduler*>(p); 199   4688 auto* self = static_cast<epoll_scheduler*>(p);
HITCBC 200   4809 self->timerfd_stale_.store(true, std::memory_order_release); 200   4688 self->timerfd_stale_.store(true, std::memory_order_release);
HITCBC 201   4809 self->interrupt_reactor(); 201   4688 self->interrupt_reactor();
HITCBC 202   4809 })); 202   4688 }));
203   203  
HITCBC 204   593 get_resolver_service(ctx, *this); 204   593 get_resolver_service(ctx, *this);
HITCBC 205   593 get_signal_service(ctx, *this); 205   593 get_signal_service(ctx, *this);
HITCBC 206   593 get_stream_file_service(ctx, *this); 206   593 get_stream_file_service(ctx, *this);
HITCBC 207   593 get_random_access_file_service(ctx, *this); 207   593 get_random_access_file_service(ctx, *this);
208   208  
HITCBC 209   593 completed_ops_.push(&task_op_); 209   593 completed_ops_.push(&task_op_);
HITCBC 210   593 } 210   593 }
211   211  
HITCBC 212   1186 inline epoll_scheduler::~epoll_scheduler() 212   1186 inline epoll_scheduler::~epoll_scheduler()
213   { 213   {
HITCBC 214   593 if (timer_fd_ >= 0) 214   593 if (timer_fd_ >= 0)
HITCBC 215   593 ::close(timer_fd_); 215   593 ::close(timer_fd_);
HITCBC 216   593 if (event_fd_ >= 0) 216   593 if (event_fd_ >= 0)
HITCBC 217   593 ::close(event_fd_); 217   593 ::close(event_fd_);
HITCBC 218   593 if (epoll_fd_ >= 0) 218   593 if (epoll_fd_ >= 0)
HITCBC 219   593 ::close(epoll_fd_); 219   593 ::close(epoll_fd_);
HITCBC 220   1186 } 220   1186 }
221   221  
222   inline void 222   inline void
HITCBC 223   593 epoll_scheduler::shutdown() 223   593 epoll_scheduler::shutdown()
224   { 224   {
HITCBC 225   593 shutdown_drain(); 225   593 shutdown_drain();
226   226  
HITCBC 227   593 if (event_fd_ >= 0) 227   593 if (event_fd_ >= 0)
HITCBC 228   593 interrupt_reactor(); 228   593 interrupt_reactor();
HITCBC 229   593 } 229   593 }
230   230  
231   inline void 231   inline void
HITCBC 232   8 epoll_scheduler::configure_reactor( 232   8 epoll_scheduler::configure_reactor(
233   unsigned max_events, 233   unsigned max_events,
234   unsigned budget_init, 234   unsigned budget_init,
235   unsigned budget_max, 235   unsigned budget_max,
236   unsigned unassisted) 236   unsigned unassisted)
237   { 237   {
HITCBC 238   8 reactor_scheduler::configure_reactor( 238   8 reactor_scheduler::configure_reactor(
239   max_events, budget_init, budget_max, unassisted); 239   max_events, budget_init, budget_max, unassisted);
HITCBC 240   7 event_buffer_.resize(max_events_per_poll_); 240   7 event_buffer_.resize(max_events_per_poll_);
HITCBC 241   7 } 241   7 }
242   242  
243   inline void 243   inline void
HITCBC 244   9464 epoll_scheduler::register_descriptor(int fd, reactor_descriptor_state* desc) const 244   9228 epoll_scheduler::register_descriptor(int fd, reactor_descriptor_state* desc) const
245   { 245   {
HITCBC 246   9464 epoll_event ev{}; 246   9228 epoll_event ev{};
HITCBC 247   9464 ev.events = EPOLLIN | EPOLLOUT | EPOLLET | EPOLLERR | EPOLLHUP; 247   9228 ev.events = EPOLLIN | EPOLLOUT | EPOLLET | EPOLLERR | EPOLLHUP;
HITCBC 248   9464 ev.data.ptr = desc; 248   9228 ev.data.ptr = desc;
249   249  
HITCBC 250   9464 if (::epoll_ctl(epoll_fd_, EPOLL_CTL_ADD, fd, &ev) < 0) 250   9228 if (::epoll_ctl(epoll_fd_, EPOLL_CTL_ADD, fd, &ev) < 0)
MISUBC 251   ✗ detail::throw_system_error(make_err(errno), "epoll_ctl (register)"); 251   ✗ detail::throw_system_error(make_err(errno), "epoll_ctl (register)");
252   252  
HITCBC 253   9464 desc->registered_events = ev.events; 253   9228 desc->registered_events = ev.events;
HITCBC 254   9464 desc->fd = fd; 254   9228 desc->fd = fd;
HITCBC 255   9464 desc->scheduler_ = this; 255   9228 desc->scheduler_ = this;
HITCBC 256   9464 desc->mutex.set_enabled(!single_threaded_); 256   9228 desc->mutex.set_enabled(!single_threaded_);
HITCBC 257   9464 desc->ready_events_.store(0, std::memory_order_relaxed); 257   9228 desc->ready_events_.store(0, std::memory_order_relaxed);
258   258  
HITCBC 259   9464 conditionally_enabled_mutex::scoped_lock lock(desc->mutex); 259   9228 conditionally_enabled_mutex::scoped_lock lock(desc->mutex);
HITCBC 260   9464 desc->impl_ref_.reset(); 260   9228 desc->impl_ref_.reset();
HITCBC 261   9464 desc->read_ready = false; 261   9228 desc->read_ready = false;
HITCBC 262   9464 desc->write_ready = false; 262   9228 desc->write_ready = false;
HITCBC 263   9464 } 263   9228 }
264   264  
265   inline void 265   inline void
HITCBC 266   9464 epoll_scheduler::deregister_descriptor(int fd) const 266   9228 epoll_scheduler::deregister_descriptor(int fd) const
267   { 267   {
HITCBC 268   9464 ::epoll_ctl(epoll_fd_, EPOLL_CTL_DEL, fd, nullptr); 268   9228 ::epoll_ctl(epoll_fd_, EPOLL_CTL_DEL, fd, nullptr);
HITCBC 269   9464 } 269   9228 }
270   270  
271   inline void 271   inline void
HITCBC 272   5860 epoll_scheduler::interrupt_reactor() const 272   5741 epoll_scheduler::interrupt_reactor() const
273   { 273   {
HITCBC 274   5860 bool expected = false; 274   5741 bool expected = false;
HITCBC 275   5860 if (eventfd_armed_.compare_exchange_strong( 275   5741 if (eventfd_armed_.compare_exchange_strong(
276   expected, true, std::memory_order_release, 276   expected, true, std::memory_order_release,
277   std::memory_order_relaxed)) 277   std::memory_order_relaxed))
278   { 278   {
HITCBC 279   5508 std::uint64_t val = 1; 279   5389 std::uint64_t val = 1;
HITCBC 280   5508 [[maybe_unused]] auto r = ::write(event_fd_, &val, sizeof(val)); 280   5389 [[maybe_unused]] auto r = ::write(event_fd_, &val, sizeof(val));
281   } 281   }
HITCBC 282   5860 } 282   5741 }
283   283  
284   inline void 284   inline void
HITCBC 285   9575 epoll_scheduler::update_timerfd() const 285   9332 epoll_scheduler::update_timerfd() const
286   { 286   {
HITCBC 287   9575 auto nearest = timer_svc_->nearest_expiry(); 287   9332 auto nearest = timer_svc_->nearest_expiry();
288   288  
HITCBC 289   9575 itimerspec ts{}; 289   9332 itimerspec ts{};
HITCBC 290   9575 int flags = 0; 290   9332 int flags = 0;
291   291  
HITCBC 292   9575 if (nearest == timer_service::time_point::max()) 292   9332 if (nearest == timer_service::time_point::max())
293   { 293   {
294   // No timers — disarm by setting to 0 (relative) 294   // No timers — disarm by setting to 0 (relative)
295   } 295   }
296   else 296   else
297   { 297   {
HITCBC 298   9477 auto now = std::chrono::steady_clock::now(); 298   9234 auto now = std::chrono::steady_clock::now();
HITCBC 299   9477 if (nearest <= now) 299   9234 if (nearest <= now)
300   { 300   {
301   // Use 1ns instead of 0 — zero disarms the timerfd 301   // Use 1ns instead of 0 — zero disarms the timerfd
HITCBC 302   351 ts.it_value.tv_nsec = 1; 302   551 ts.it_value.tv_nsec = 1;
303   } 303   }
304   else 304   else
305   { 305   {
HITCBC 306   9126 auto nsec = std::chrono::duration_cast<std::chrono::nanoseconds>( 306   8683 auto nsec = std::chrono::duration_cast<std::chrono::nanoseconds>(
HITCBC 307   9126 nearest - now) 307   8683 nearest - now)
HITCBC 308   9126 .count(); 308   8683 .count();
HITCBC 309   9126 ts.it_value.tv_sec = nsec / 1000000000; 309   8683 ts.it_value.tv_sec = nsec / 1000000000;
HITCBC 310   9126 ts.it_value.tv_nsec = nsec % 1000000000; 310   8683 ts.it_value.tv_nsec = nsec % 1000000000;
HITCBC 311   9126 if (ts.it_value.tv_sec == 0 && ts.it_value.tv_nsec == 0) 311   8683 if (ts.it_value.tv_sec == 0 && ts.it_value.tv_nsec == 0)
MISUBC 312   ✗ ts.it_value.tv_nsec = 1; 312   ✗ ts.it_value.tv_nsec = 1;
313   } 313   }
314   } 314   }
315   315  
HITCBC 316   9575 if (::timerfd_settime(timer_fd_, flags, &ts, nullptr) < 0) 316   9332 if (::timerfd_settime(timer_fd_, flags, &ts, nullptr) < 0)
MISUBC 317   ✗ detail::throw_system_error(make_err(errno), "timerfd_settime"); 317   ✗ detail::throw_system_error(make_err(errno), "timerfd_settime");
HITCBC 318   9575 } 318   9332 }
319   319  
320   inline void 320   inline void
HITCBC 321   45388 epoll_scheduler::run_task( 321   37763 epoll_scheduler::run_task(
322   lock_type& lock, context_type* ctx, long timeout_us) 322   lock_type& lock, context_type* ctx, long timeout_us)
323   { 323   {
324   int timeout_ms; 324   int timeout_ms;
HITCBC 325   45388 if (task_interrupted_) 325   37763 if (task_interrupted_)
HITCBC 326   31813 timeout_ms = 0; 326   24982 timeout_ms = 0;
HITCBC 327   13575 else if (timeout_us < 0) 327   12781 else if (timeout_us < 0)
HITCBC 328   13571 timeout_ms = -1; 328   12777 timeout_ms = -1;
329   else 329   else
HITCBC 330   4 timeout_ms = static_cast<int>((timeout_us + 999) / 1000); 330   4 timeout_ms = static_cast<int>((timeout_us + 999) / 1000);
331   331  
HITCBC 332   45388 if (lock.owns_lock()) 332   37763 if (lock.owns_lock())
HITCBC 333   13575 lock.unlock(); 333   12781 lock.unlock();
334   334  
HITCBC 335   45388 task_cleanup on_exit{this, &lock, ctx}; 335   37763 task_cleanup on_exit{this, &lock, ctx};
336   336  
337   // Flush deferred timerfd programming before blocking 337   // Flush deferred timerfd programming before blocking
HITCBC 338   45388 if (timerfd_stale_.exchange(false, std::memory_order_acquire)) 338   37763 if (timerfd_stale_.exchange(false, std::memory_order_acquire))
HITCBC 339   4785 update_timerfd(); 339   4664 update_timerfd();
340   340  
HITCBC 341   45388 int nfds = ::epoll_wait( 341   37763 int nfds = ::epoll_wait(
342   epoll_fd_, event_buffer_.data(), 342   epoll_fd_, event_buffer_.data(),
HITCBC 343   45388 static_cast<int>(event_buffer_.size()), timeout_ms); 343   37763 static_cast<int>(event_buffer_.size()), timeout_ms);
344   344  
HITCBC 345   45388 if (nfds < 0 && errno != EINTR) 345   37763 if (nfds < 0 && errno != EINTR)
MISUBC 346   ✗ detail::throw_system_error(make_err(errno), "epoll_wait"); 346   ✗ detail::throw_system_error(make_err(errno), "epoll_wait");
347   347  
HITCBC 348   45388 bool check_timers = false; 348   37763 bool check_timers = false;
HITCBC 349   45388 op_queue local_ops; 349   37763 op_queue local_ops;
350   350  
HITCBC 351   103555 for (int i = 0; i < nfds; ++i) 351   85727 for (int i = 0; i < nfds; ++i)
352   { 352   {
HITCBC 353   58167 if (event_buffer_[i].data.ptr == nullptr) 353   47964 if (event_buffer_[i].data.ptr == nullptr)
354   { 354   {
355   std::uint64_t val; 355   std::uint64_t val;
356   // NOLINTNEXTLINE(clang-analyzer-unix.BlockInCriticalSection) 356   // NOLINTNEXTLINE(clang-analyzer-unix.BlockInCriticalSection)
HITCBC 357   4915 [[maybe_unused]] auto r = ::read(event_fd_, &val, sizeof(val)); 357   4796 [[maybe_unused]] auto r = ::read(event_fd_, &val, sizeof(val));
HITCBC 358   4915 eventfd_armed_.store(false, std::memory_order_relaxed); 358   4796 eventfd_armed_.store(false, std::memory_order_relaxed);
HITCBC 359   4915 continue; 359   4796 continue;
HITCBC 360   4915 } 360   4796 }
361   361  
HITCBC 362   53252 if (event_buffer_[i].data.ptr == &timer_fd_) 362   43168 if (event_buffer_[i].data.ptr == &timer_fd_)
363   { 363   {
364   std::uint64_t expirations; 364   std::uint64_t expirations;
365   // NOLINTNEXTLINE(clang-analyzer-unix.BlockInCriticalSection) 365   // NOLINTNEXTLINE(clang-analyzer-unix.BlockInCriticalSection)
366   [[maybe_unused]] auto r = 366   [[maybe_unused]] auto r =
HITCBC 367   4790 ::read(timer_fd_, &expirations, sizeof(expirations)); 367   4668 ::read(timer_fd_, &expirations, sizeof(expirations));
HITCBC 368   4790 check_timers = true; 368   4668 check_timers = true;
HITCBC 369   4790 continue; 369   4668 continue;
HITCBC 370   4790 } 370   4668 }
371   371  
372   auto* desc = 372   auto* desc =
HITCBC 373   48462 static_cast<reactor_descriptor_state*>(event_buffer_[i].data.ptr); 373   38500 static_cast<reactor_descriptor_state*>(event_buffer_[i].data.ptr);
HITCBC 374   48462 desc->add_ready_events(event_buffer_[i].events); 374   38500 desc->add_ready_events(event_buffer_[i].events);
375   375  
HITCBC 376   48462 bool expected = false; 376   38500 bool expected = false;
HITCBC 377   48462 if (desc->is_enqueued_.compare_exchange_strong( 377   38500 if (desc->is_enqueued_.compare_exchange_strong(
378   expected, true, std::memory_order_release, 378   expected, true, std::memory_order_release,
379   std::memory_order_relaxed)) 379   std::memory_order_relaxed))
380   { 380   {
HITCBC 381   48462 local_ops.push(desc); 381   38500 local_ops.push(desc);
382   } 382   }
383   } 383   }
384   384  
HITCBC 385   45388 if (check_timers) 385   37763 if (check_timers)
386   { 386   {
HITCBC 387   4790 timer_svc_->process_expired(); 387   4668 timer_svc_->process_expired();
HITCBC 388   4790 update_timerfd(); 388   4668 update_timerfd();
389   } 389   }
390   390  
HITCBC 391   45388 lock.lock(); 391   37763 lock.lock();
392   392  
HITCBC 393   45388 if (!local_ops.empty()) 393   37763 if (!local_ops.empty())
HITCBC 394   31231 completed_ops_.splice(local_ops); 394   24405 completed_ops_.splice(local_ops);
HITCBC 395   45388 } 395   37763 }
396   396  
397   } // namespace boost::corosio::detail 397   } // namespace boost::corosio::detail
398   398  
399   #endif // BOOST_COROSIO_HAS_EPOLL 399   #endif // BOOST_COROSIO_HAS_EPOLL
400   400  
401   #endif // BOOST_COROSIO_NATIVE_DETAIL_EPOLL_EPOLL_SCHEDULER_HPP 401   #endif // BOOST_COROSIO_NATIVE_DETAIL_EPOLL_EPOLL_SCHEDULER_HPP