. /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   5028 timer_service::callback(this, [](void* p) { 198   5246 timer_service::callback(this, [](void* p) {
HITCBC 199   4435 auto* self = static_cast<epoll_scheduler*>(p); 199   4653 auto* self = static_cast<epoll_scheduler*>(p);
HITCBC 200   4435 self->timerfd_stale_.store(true, std::memory_order_release); 200   4653 self->timerfd_stale_.store(true, std::memory_order_release);
HITCBC 201   4435 self->interrupt_reactor(); 201   4653 self->interrupt_reactor();
HITCBC 202   4435 })); 202   4653 }));
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   8730 epoll_scheduler::register_descriptor(int fd, reactor_descriptor_state* desc) const 244   9158 epoll_scheduler::register_descriptor(int fd, reactor_descriptor_state* desc) const
245   { 245   {
HITCBC 246   8730 epoll_event ev{}; 246   9158 epoll_event ev{};
HITCBC 247   8730 ev.events = EPOLLIN | EPOLLOUT | EPOLLET | EPOLLERR | EPOLLHUP; 247   9158 ev.events = EPOLLIN | EPOLLOUT | EPOLLET | EPOLLERR | EPOLLHUP;
HITCBC 248   8730 ev.data.ptr = desc; 248   9158 ev.data.ptr = desc;
249   249  
HITCBC 250   8730 if (::epoll_ctl(epoll_fd_, EPOLL_CTL_ADD, fd, &ev) < 0) 250   9158 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   8730 desc->registered_events = ev.events; 253   9158 desc->registered_events = ev.events;
HITCBC 254   8730 desc->fd = fd; 254   9158 desc->fd = fd;
HITCBC 255   8730 desc->scheduler_ = this; 255   9158 desc->scheduler_ = this;
HITCBC 256   8730 desc->mutex.set_enabled(!single_threaded_); 256   9158 desc->mutex.set_enabled(!single_threaded_);
HITCBC 257   8730 desc->ready_events_.store(0, std::memory_order_relaxed); 257   9158 desc->ready_events_.store(0, std::memory_order_relaxed);
258   258  
HITCBC 259   8730 conditionally_enabled_mutex::scoped_lock lock(desc->mutex); 259   9158 conditionally_enabled_mutex::scoped_lock lock(desc->mutex);
HITCBC 260   8730 desc->impl_ref_.reset(); 260   9158 desc->impl_ref_.reset();
HITCBC 261   8730 desc->read_ready = false; 261   9158 desc->read_ready = false;
HITCBC 262   8730 desc->write_ready = false; 262   9158 desc->write_ready = false;
HITCBC 263   8730 } 263   9158 }
264   264  
265   inline void 265   inline void
HITCBC 266   8730 epoll_scheduler::deregister_descriptor(int fd) const 266   9158 epoll_scheduler::deregister_descriptor(int fd) const
267   { 267   {
HITCBC 268   8730 ::epoll_ctl(epoll_fd_, EPOLL_CTL_DEL, fd, nullptr); 268   9158 ::epoll_ctl(epoll_fd_, EPOLL_CTL_DEL, fd, nullptr);
HITCBC 269   8730 } 269   9158 }
270   270  
271   inline void 271   inline void
HITCBC 272   5494 epoll_scheduler::interrupt_reactor() const 272   5705 epoll_scheduler::interrupt_reactor() const
273   { 273   {
HITCBC 274   5494 bool expected = false; 274   5705 bool expected = false;
HITCBC 275   5494 if (eventfd_armed_.compare_exchange_strong( 275   5705 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   5142 std::uint64_t val = 1; 279   5352 std::uint64_t val = 1;
HITCBC 280   5142 [[maybe_unused]] auto r = ::write(event_fd_, &val, sizeof(val)); 280   5352 [[maybe_unused]] auto r = ::write(event_fd_, &val, sizeof(val));
281   } 281   }
HITCBC 282   5494 } 282   5705 }
283   283  
284   inline void 284   inline void
HITCBC 285   8826 epoll_scheduler::update_timerfd() const 285   9264 epoll_scheduler::update_timerfd() const
286   { 286   {
HITCBC 287   8826 auto nearest = timer_svc_->nearest_expiry(); 287   9264 auto nearest = timer_svc_->nearest_expiry();
288   288  
HITCBC 289   8826 itimerspec ts{}; 289   9264 itimerspec ts{};
HITCBC 290   8826 int flags = 0; 290   9264 int flags = 0;
291   291  
HITCBC 292   8826 if (nearest == timer_service::time_point::max()) 292   9264 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   8730 auto now = std::chrono::steady_clock::now(); 298   9167 auto now = std::chrono::steady_clock::now();
HITCBC 299   8730 if (nearest <= now) 299   9167 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   434 ts.it_value.tv_nsec = 1; 302   468 ts.it_value.tv_nsec = 1;
303   } 303   }
304   else 304   else
305   { 305   {
HITCBC 306   8296 auto nsec = std::chrono::duration_cast<std::chrono::nanoseconds>( 306   8699 auto nsec = std::chrono::duration_cast<std::chrono::nanoseconds>(
HITCBC 307   8296 nearest - now) 307   8699 nearest - now)
HITCBC 308   8296 .count(); 308   8699 .count();
HITCBC 309   8296 ts.it_value.tv_sec = nsec / 1000000000; 309   8699 ts.it_value.tv_sec = nsec / 1000000000;
HITCBC 310   8296 ts.it_value.tv_nsec = nsec % 1000000000; 310   8699 ts.it_value.tv_nsec = nsec % 1000000000;
HITCBC 311   8296 if (ts.it_value.tv_sec == 0 && ts.it_value.tv_nsec == 0) 311   8699 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   8826 if (::timerfd_settime(timer_fd_, flags, &ts, nullptr) < 0) 316   9264 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   8826 } 318   9264 }
319   319  
320   inline void 320   inline void
HITCBC 321   35968 epoll_scheduler::run_task( 321   45384 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   35968 if (task_interrupted_) 325   45384 if (task_interrupted_)
HITCBC 326   23539 timeout_ms = 0; 326   32398 timeout_ms = 0;
HITCBC 327   12429 else if (timeout_us < 0) 327   12986 else if (timeout_us < 0)
HITCBC 328   12425 timeout_ms = -1; 328   12982 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   35968 if (lock.owns_lock()) 332   45384 if (lock.owns_lock())
HITCBC 333   12429 lock.unlock(); 333   12986 lock.unlock();
334   334  
HITCBC 335   35968 task_cleanup on_exit{this, &lock, ctx}; 335   45384 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   35968 if (timerfd_stale_.exchange(false, std::memory_order_acquire)) 338   45384 if (timerfd_stale_.exchange(false, std::memory_order_acquire))
HITCBC 339   4411 update_timerfd(); 339   4629 update_timerfd();
340   340  
HITCBC 341   35968 int nfds = ::epoll_wait( 341   45384 int nfds = ::epoll_wait(
342   epoll_fd_, event_buffer_.data(), 342   epoll_fd_, event_buffer_.data(),
HITCBC 343   35968 static_cast<int>(event_buffer_.size()), timeout_ms); 343   45384 static_cast<int>(event_buffer_.size()), timeout_ms);
344   344  
HITCBC 345   35968 if (nfds < 0 && errno != EINTR) 345   45384 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   35968 bool check_timers = false; 348   45384 bool check_timers = false;
HITCBC 349   35968 op_queue local_ops; 349   45384 op_queue local_ops;
350   350  
HITCBC 351   81749 for (int i = 0; i < nfds; ++i) 351   103727 for (int i = 0; i < nfds; ++i)
352   { 352   {
HITCBC 353   45781 if (event_buffer_[i].data.ptr == nullptr) 353   58343 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   4549 [[maybe_unused]] auto r = ::read(event_fd_, &val, sizeof(val)); 357   4759 [[maybe_unused]] auto r = ::read(event_fd_, &val, sizeof(val));
HITCBC 358   4549 eventfd_armed_.store(false, std::memory_order_relaxed); 358   4759 eventfd_armed_.store(false, std::memory_order_relaxed);
HITCBC 359   4549 continue; 359   4759 continue;
HITCBC 360   4549 } 360   4759 }
361   361  
HITCBC 362   41232 if (event_buffer_[i].data.ptr == &timer_fd_) 362   53584 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   4415 ::read(timer_fd_, &expirations, sizeof(expirations)); 367   4635 ::read(timer_fd_, &expirations, sizeof(expirations));
HITCBC 368   4415 check_timers = true; 368   4635 check_timers = true;
HITCBC 369   4415 continue; 369   4635 continue;
HITCBC 370   4415 } 370   4635 }
371   371  
372   auto* desc = 372   auto* desc =
HITCBC 373   36817 static_cast<reactor_descriptor_state*>(event_buffer_[i].data.ptr); 373   48949 static_cast<reactor_descriptor_state*>(event_buffer_[i].data.ptr);
HITCBC 374   36817 desc->add_ready_events(event_buffer_[i].events); 374   48949 desc->add_ready_events(event_buffer_[i].events);
375   375  
HITCBC 376   36817 bool expected = false; 376   48949 bool expected = false;
HITCBC 377   36817 if (desc->is_enqueued_.compare_exchange_strong( 377   48949 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   36817 local_ops.push(desc); 381   48949 local_ops.push(desc);
382   } 382   }
383   } 383   }
384   384  
HITCBC 385   35968 if (check_timers) 385   45384 if (check_timers)
386   { 386   {
HITCBC 387   4415 timer_svc_->process_expired(); 387   4635 timer_svc_->process_expired();
HITCBC 388   4415 update_timerfd(); 388   4635 update_timerfd();
389   } 389   }
390   390  
HITCBC 391   35968 lock.lock(); 391   45384 lock.lock();
392   392  
HITCBC 393   35968 if (!local_ops.empty()) 393   45384 if (!local_ops.empty())
HITCBC 394   22971 completed_ops_.splice(local_ops); 394   31817 completed_ops_.splice(local_ops);
HITCBC 395   35968 } 395   45384 }
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