. /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   373 inline epoll_scheduler::epoll_scheduler(capy::execution_context& ctx, int) 145   373 inline epoll_scheduler::epoll_scheduler(capy::execution_context& ctx, int)
HITCBC 146   373 : epoll_fd_(-1) 146   373 : epoll_fd_(-1)
HITCBC 147   373 , event_fd_(-1) 147   373 , event_fd_(-1)
HITCBC 148   373 , timer_fd_(-1) 148   373 , timer_fd_(-1)
HITCBC 149   746 , event_buffer_(max_events_per_poll_) 149   746 , event_buffer_(max_events_per_poll_)
150   { 150   {
HITCBC 151   373 epoll_fd_ = ::epoll_create1(EPOLL_CLOEXEC); 151   373 epoll_fd_ = ::epoll_create1(EPOLL_CLOEXEC);
HITCBC 152   373 if (epoll_fd_ < 0) 152   373 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   373 event_fd_ = ::eventfd(0, EFD_NONBLOCK | EFD_CLOEXEC); 155   373 event_fd_ = ::eventfd(0, EFD_NONBLOCK | EFD_CLOEXEC);
HITCBC 156   373 if (event_fd_ < 0) 156   373 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   373 timer_fd_ = ::timerfd_create(CLOCK_MONOTONIC, TFD_NONBLOCK | TFD_CLOEXEC); 163   373 timer_fd_ = ::timerfd_create(CLOCK_MONOTONIC, TFD_NONBLOCK | TFD_CLOEXEC);
HITCBC 164   373 if (timer_fd_ < 0) 164   373 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   373 epoll_event ev{}; 172   373 epoll_event ev{};
HITCBC 173   373 ev.events = EPOLLIN | EPOLLET; 173   373 ev.events = EPOLLIN | EPOLLET;
HITCBC 174   373 ev.data.ptr = nullptr; 174   373 ev.data.ptr = nullptr;
HITCBC 175   373 if (::epoll_ctl(epoll_fd_, EPOLL_CTL_ADD, event_fd_, &ev) < 0) 175   373 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   373 epoll_event timer_ev{}; 184   373 epoll_event timer_ev{};
HITCBC 185   373 timer_ev.events = EPOLLIN | EPOLLERR; 185   373 timer_ev.events = EPOLLIN | EPOLLERR;
HITCBC 186   373 timer_ev.data.ptr = &timer_fd_; 186   373 timer_ev.data.ptr = &timer_fd_;
HITCBC 187   373 if (::epoll_ctl(epoll_fd_, EPOLL_CTL_ADD, timer_fd_, &timer_ev) < 0) 187   373 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   373 timer_svc_ = &get_timer_service(ctx, *this); 196   373 timer_svc_ = &get_timer_service(ctx, *this);
HITCBC 197   373 timer_svc_->set_on_earliest_changed( 197   373 timer_svc_->set_on_earliest_changed(
HITCBC 198   5323 timer_service::callback(this, [](void* p) { 198   5444 timer_service::callback(this, [](void* p) {
HITCBC 199   4950 auto* self = static_cast<epoll_scheduler*>(p); 199   5071 auto* self = static_cast<epoll_scheduler*>(p);
HITCBC 200   4950 self->timerfd_stale_.store(true, std::memory_order_release); 200   5071 self->timerfd_stale_.store(true, std::memory_order_release);
HITCBC 201   4950 self->interrupt_reactor(); 201   5071 self->interrupt_reactor();
HITCBC 202   4950 })); 202   5071 }));
203   203  
HITCBC 204   373 get_resolver_service(ctx, *this); 204   373 get_resolver_service(ctx, *this);
HITCBC 205   373 get_signal_service(ctx, *this); 205   373 get_signal_service(ctx, *this);
HITCBC 206   373 get_stream_file_service(ctx, *this); 206   373 get_stream_file_service(ctx, *this);
HITCBC 207   373 get_random_access_file_service(ctx, *this); 207   373 get_random_access_file_service(ctx, *this);
208   208  
HITCBC 209   373 completed_ops_.push(&task_op_); 209   373 completed_ops_.push(&task_op_);
HITCBC 210   373 } 210   373 }
211   211  
HITCBC 212   746 inline epoll_scheduler::~epoll_scheduler() 212   746 inline epoll_scheduler::~epoll_scheduler()
213   { 213   {
HITCBC 214   373 if (timer_fd_ >= 0) 214   373 if (timer_fd_ >= 0)
HITCBC 215   373 ::close(timer_fd_); 215   373 ::close(timer_fd_);
HITCBC 216   373 if (event_fd_ >= 0) 216   373 if (event_fd_ >= 0)
HITCBC 217   373 ::close(event_fd_); 217   373 ::close(event_fd_);
HITCBC 218   373 if (epoll_fd_ >= 0) 218   373 if (epoll_fd_ >= 0)
HITCBC 219   373 ::close(epoll_fd_); 219   373 ::close(epoll_fd_);
HITCBC 220   746 } 220   746 }
221   221  
222   inline void 222   inline void
HITCBC 223   373 epoll_scheduler::shutdown() 223   373 epoll_scheduler::shutdown()
224   { 224   {
HITCBC 225   373 shutdown_drain(); 225   373 shutdown_drain();
226   226  
HITCBC 227   373 if (event_fd_ >= 0) 227   373 if (event_fd_ >= 0)
HITCBC 228   373 interrupt_reactor(); 228   373 interrupt_reactor();
HITCBC 229   373 } 229   373 }
230   230  
231   inline void 231   inline void
MISUBC 232   ✗ epoll_scheduler::configure_reactor( 232   ✗ 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   {
MISUBC 238   ✗ reactor_scheduler::configure_reactor( 238   ✗ reactor_scheduler::configure_reactor(
239   max_events, budget_init, budget_max, unassisted); 239   max_events, budget_init, budget_max, unassisted);
MISUBC 240   ✗ event_buffer_.resize(max_events_per_poll_); 240   ✗ event_buffer_.resize(max_events_per_poll_);
MISUBC 241   ✗ } 241   ✗ }
242   242  
243   inline void 243   inline void
HITCBC 244   9644 epoll_scheduler::register_descriptor(int fd, reactor_descriptor_state* desc) const 244   9880 epoll_scheduler::register_descriptor(int fd, reactor_descriptor_state* desc) const
245   { 245   {
HITCBC 246   9644 epoll_event ev{}; 246   9880 epoll_event ev{};
HITCBC 247   9644 ev.events = EPOLLIN | EPOLLOUT | EPOLLET | EPOLLERR | EPOLLHUP; 247   9880 ev.events = EPOLLIN | EPOLLOUT | EPOLLET | EPOLLERR | EPOLLHUP;
HITCBC 248   9644 ev.data.ptr = desc; 248   9880 ev.data.ptr = desc;
249   249  
HITCBC 250   9644 if (::epoll_ctl(epoll_fd_, EPOLL_CTL_ADD, fd, &ev) < 0) 250   9880 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   9644 desc->registered_events = ev.events; 253   9880 desc->registered_events = ev.events;
HITCBC 254   9644 desc->fd = fd; 254   9880 desc->fd = fd;
HITCBC 255   9644 desc->scheduler_ = this; 255   9880 desc->scheduler_ = this;
HITCBC 256   9644 desc->mutex.set_enabled(!single_threaded_); 256   9880 desc->mutex.set_enabled(!single_threaded_);
HITCBC 257   9644 desc->ready_events_.store(0, std::memory_order_relaxed); 257   9880 desc->ready_events_.store(0, std::memory_order_relaxed);
258   258  
HITCBC 259   9644 conditionally_enabled_mutex::scoped_lock lock(desc->mutex); 259   9880 conditionally_enabled_mutex::scoped_lock lock(desc->mutex);
HITCBC 260   9644 desc->impl_ref_.reset(); 260   9880 desc->impl_ref_.reset();
HITCBC 261   9644 desc->read_ready = false; 261   9880 desc->read_ready = false;
HITCBC 262   9644 desc->write_ready = false; 262   9880 desc->write_ready = false;
HITCBC 263   9644 } 263   9880 }
264   264  
265   inline void 265   inline void
HITCBC 266   9644 epoll_scheduler::deregister_descriptor(int fd) const 266   9880 epoll_scheduler::deregister_descriptor(int fd) const
267   { 267   {
HITCBC 268   9644 ::epoll_ctl(epoll_fd_, EPOLL_CTL_DEL, fd, nullptr); 268   9880 ::epoll_ctl(epoll_fd_, EPOLL_CTL_DEL, fd, nullptr);
HITCBC 269   9644 } 269   9880 }
270   270  
271   inline void 271   inline void
HITCBC 272   5642 epoll_scheduler::interrupt_reactor() const 272   5767 epoll_scheduler::interrupt_reactor() const
273   { 273   {
HITCBC 274   5642 bool expected = false; 274   5767 bool expected = false;
HITCBC 275   5642 if (eventfd_armed_.compare_exchange_strong( 275   5767 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   5402 std::uint64_t val = 1; 279   5530 std::uint64_t val = 1;
HITCBC 280   5402 [[maybe_unused]] auto r = ::write(event_fd_, &val, sizeof(val)); 280   5530 [[maybe_unused]] auto r = ::write(event_fd_, &val, sizeof(val));
281   } 281   }
HITCBC 282   5642 } 282   5767 }
283   283  
284   inline void 284   inline void
HITCBC 285   9860 epoll_scheduler::update_timerfd() const 285   10101 epoll_scheduler::update_timerfd() const
286   { 286   {
HITCBC 287   9860 auto nearest = timer_svc_->nearest_expiry(); 287   10101 auto nearest = timer_svc_->nearest_expiry();
288   288  
HITCBC 289   9860 itimerspec ts{}; 289   10101 itimerspec ts{};
HITCBC 290   9860 int flags = 0; 290   10101 int flags = 0;
291   291  
HITCBC 292   9860 if (nearest == timer_service::time_point::max()) 292   10101 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   9803 auto now = std::chrono::steady_clock::now(); 298   10043 auto now = std::chrono::steady_clock::now();
HITCBC 299   9803 if (nearest <= now) 299   10043 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   525 ts.it_value.tv_nsec = 1; 302   392 ts.it_value.tv_nsec = 1;
303   } 303   }
304   else 304   else
305   { 305   {
HITCBC 306   9278 auto nsec = std::chrono::duration_cast<std::chrono::nanoseconds>( 306   9651 auto nsec = std::chrono::duration_cast<std::chrono::nanoseconds>(
HITCBC 307   9278 nearest - now) 307   9651 nearest - now)
HITCBC 308   9278 .count(); 308   9651 .count();
HITCBC 309   9278 ts.it_value.tv_sec = nsec / 1000000000; 309   9651 ts.it_value.tv_sec = nsec / 1000000000;
HITCBC 310   9278 ts.it_value.tv_nsec = nsec % 1000000000; 310   9651 ts.it_value.tv_nsec = nsec % 1000000000;
HITCBC 311   9278 if (ts.it_value.tv_sec == 0 && ts.it_value.tv_nsec == 0) 311   9651 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   9860 if (::timerfd_settime(timer_fd_, flags, &ts, nullptr) < 0) 316   10101 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   9860 } 318   10101 }
319   319  
320   inline void 320   inline void
HITCBC 321   40357 epoll_scheduler::run_task( 321   41290 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   40357 if (task_interrupted_) 325   41290 if (task_interrupted_)
HITCBC 326   27218 timeout_ms = 0; 326   27196 timeout_ms = 0;
HITCBC 327   13139 else if (timeout_us < 0) 327   14094 else if (timeout_us < 0)
HITCBC 328   13131 timeout_ms = -1; 328   14086 timeout_ms = -1;
329   else 329   else
HITCBC 330   8 timeout_ms = static_cast<int>((timeout_us + 999) / 1000); 330   8 timeout_ms = static_cast<int>((timeout_us + 999) / 1000);
331   331  
HITCBC 332   40357 if (lock.owns_lock()) 332   41290 if (lock.owns_lock())
HITCBC 333   13139 lock.unlock(); 333   14094 lock.unlock();
334   334  
HITCBC 335   40357 task_cleanup on_exit{this, &lock, ctx}; 335   41290 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   40357 if (timerfd_stale_.exchange(false, std::memory_order_acquire)) 338   41290 if (timerfd_stale_.exchange(false, std::memory_order_acquire))
HITCBC 339   4928 update_timerfd(); 339   5049 update_timerfd();
340   340  
HITCBC 341   40357 int nfds = ::epoll_wait( 341   41290 int nfds = ::epoll_wait(
342   epoll_fd_, event_buffer_.data(), 342   epoll_fd_, event_buffer_.data(),
HITCBC 343   40357 static_cast<int>(event_buffer_.size()), timeout_ms); 343   41290 static_cast<int>(event_buffer_.size()), timeout_ms);
344   344  
HITCBC 345   40357 if (nfds < 0 && errno != EINTR) 345   41290 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   40357 bool check_timers = false; 348   41290 bool check_timers = false;
HITCBC 349   40357 op_queue local_ops; 349   41290 op_queue local_ops;
350   350  
HITCBC 351   91882 for (int i = 0; i < nfds; ++i) 351   92840 for (int i = 0; i < nfds; ++i)
352   { 352   {
HITCBC 353   51525 if (event_buffer_[i].data.ptr == nullptr) 353   51550 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   5029 [[maybe_unused]] auto r = ::read(event_fd_, &val, sizeof(val)); 357   5157 [[maybe_unused]] auto r = ::read(event_fd_, &val, sizeof(val));
HITCBC 358   5029 eventfd_armed_.store(false, std::memory_order_relaxed); 358   5157 eventfd_armed_.store(false, std::memory_order_relaxed);
HITCBC 359   5029 continue; 359   5157 continue;
HITCBC 360   5029 } 360   5157 }
361   361  
HITCBC 362   46496 if (event_buffer_[i].data.ptr == &timer_fd_) 362   46393 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   4932 ::read(timer_fd_, &expirations, sizeof(expirations)); 367   5052 ::read(timer_fd_, &expirations, sizeof(expirations));
HITCBC 368   4932 check_timers = true; 368   5052 check_timers = true;
HITCBC 369   4932 continue; 369   5052 continue;
HITCBC 370   4932 } 370   5052 }
371   371  
372   auto* desc = 372   auto* desc =
HITCBC 373   41564 static_cast<reactor_descriptor_state*>(event_buffer_[i].data.ptr); 373   41341 static_cast<reactor_descriptor_state*>(event_buffer_[i].data.ptr);
HITCBC 374   41564 desc->add_ready_events(event_buffer_[i].events); 374   41341 desc->add_ready_events(event_buffer_[i].events);
375   375  
HITCBC 376   41564 bool expected = false; 376   41341 bool expected = false;
HITCBC 377   41564 if (desc->is_enqueued_.compare_exchange_strong( 377   41341 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   41564 local_ops.push(desc); 381   41341 local_ops.push(desc);
382   } 382   }
383   } 383   }
384   384  
HITCBC 385   40357 if (check_timers) 385   41290 if (check_timers)
386   { 386   {
HITCBC 387   4932 timer_svc_->process_expired(); 387   5052 timer_svc_->process_expired();
HITCBC 388   4932 update_timerfd(); 388   5052 update_timerfd();
389   } 389   }
390   390  
HITCBC 391   40357 lock.lock(); 391   41290 lock.lock();
392   392  
HITCBC 393   40357 if (!local_ops.empty()) 393   41290 if (!local_ops.empty())
HITCBC 394   26674 completed_ops_.splice(local_ops); 394   26651 completed_ops_.splice(local_ops);
HITCBC 395   40357 } 395   41290 }
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