. /include/boost/corosio /native /detail /epoll /epoll_scheduler.hpp
82.67% Lines (124/150) 90.00% Functions (9/10)
[ ] prev/next file n p prev/next uncovered line
TLA Baseline Branch
Line Hits Code Line Hits Code
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   366 inline epoll_scheduler::epoll_scheduler(capy::execution_context& ctx, int) 145   366 inline epoll_scheduler::epoll_scheduler(capy::execution_context& ctx, int)
HITCBC 146   366 : epoll_fd_(-1) 146   366 : epoll_fd_(-1)
HITCBC 147   366 , event_fd_(-1) 147   366 , event_fd_(-1)
HITCBC 148   366 , timer_fd_(-1) 148   366 , timer_fd_(-1)
HITCBC 149   732 , event_buffer_(max_events_per_poll_) 149   732 , event_buffer_(max_events_per_poll_)
150   { 150   {
HITCBC 151   366 epoll_fd_ = ::epoll_create1(EPOLL_CLOEXEC); 151   366 epoll_fd_ = ::epoll_create1(EPOLL_CLOEXEC);
HITCBC 152   366 if (epoll_fd_ < 0) 152   366 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   366 event_fd_ = ::eventfd(0, EFD_NONBLOCK | EFD_CLOEXEC); 155   366 event_fd_ = ::eventfd(0, EFD_NONBLOCK | EFD_CLOEXEC);
HITCBC 156   366 if (event_fd_ < 0) 156   366 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   366 timer_fd_ = ::timerfd_create(CLOCK_MONOTONIC, TFD_NONBLOCK | TFD_CLOEXEC); 163   366 timer_fd_ = ::timerfd_create(CLOCK_MONOTONIC, TFD_NONBLOCK | TFD_CLOEXEC);
HITCBC 164   366 if (timer_fd_ < 0) 164   366 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   366 epoll_event ev{}; 172   366 epoll_event ev{};
HITCBC 173   366 ev.events = EPOLLIN | EPOLLET; 173   366 ev.events = EPOLLIN | EPOLLET;
HITCBC 174   366 ev.data.ptr = nullptr; 174   366 ev.data.ptr = nullptr;
HITCBC 175   366 if (::epoll_ctl(epoll_fd_, EPOLL_CTL_ADD, event_fd_, &ev) < 0) 175   366 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   366 epoll_event timer_ev{}; 184   366 epoll_event timer_ev{};
HITCBC 185   366 timer_ev.events = EPOLLIN | EPOLLERR; 185   366 timer_ev.events = EPOLLIN | EPOLLERR;
HITCBC 186   366 timer_ev.data.ptr = &timer_fd_; 186   366 timer_ev.data.ptr = &timer_fd_;
HITCBC 187   366 if (::epoll_ctl(epoll_fd_, EPOLL_CTL_ADD, timer_fd_, &timer_ev) < 0) 187   366 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   366 timer_svc_ = &get_timer_service(ctx, *this); 196   366 timer_svc_ = &get_timer_service(ctx, *this);
HITCBC 197   366 timer_svc_->set_on_earliest_changed( 197   366 timer_svc_->set_on_earliest_changed(
HITCBC 198   2964 timer_service::callback(this, [](void* p) { 198   2632 timer_service::callback(this, [](void* p) {
HITCBC 199   2598 auto* self = static_cast<epoll_scheduler*>(p); 199   2266 auto* self = static_cast<epoll_scheduler*>(p);
HITCBC 200   2598 self->timerfd_stale_.store(true, std::memory_order_release); 200   2266 self->timerfd_stale_.store(true, std::memory_order_release);
HITCBC 201   2598 self->interrupt_reactor(); 201   2266 self->interrupt_reactor();
HITCBC 202   2598 })); 202   2266 }));
203   203  
HITCBC 204   366 get_resolver_service(ctx, *this); 204   366 get_resolver_service(ctx, *this);
HITCBC 205   366 get_signal_service(ctx, *this); 205   366 get_signal_service(ctx, *this);
HITCBC 206   366 get_stream_file_service(ctx, *this); 206   366 get_stream_file_service(ctx, *this);
HITCBC 207   366 get_random_access_file_service(ctx, *this); 207   366 get_random_access_file_service(ctx, *this);
208   208  
HITCBC 209   366 completed_ops_.push(&task_op_); 209   366 completed_ops_.push(&task_op_);
HITCBC 210   366 } 210   366 }
211   211  
HITCBC 212   732 inline epoll_scheduler::~epoll_scheduler() 212   732 inline epoll_scheduler::~epoll_scheduler()
213   { 213   {
HITCBC 214   366 if (timer_fd_ >= 0) 214   366 if (timer_fd_ >= 0)
HITCBC 215   366 ::close(timer_fd_); 215   366 ::close(timer_fd_);
HITCBC 216   366 if (event_fd_ >= 0) 216   366 if (event_fd_ >= 0)
HITCBC 217   366 ::close(event_fd_); 217   366 ::close(event_fd_);
HITCBC 218   366 if (epoll_fd_ >= 0) 218   366 if (epoll_fd_ >= 0)
HITCBC 219   366 ::close(epoll_fd_); 219   366 ::close(epoll_fd_);
HITCBC 220   732 } 220   732 }
221   221  
222   inline void 222   inline void
HITCBC 223   366 epoll_scheduler::shutdown() 223   366 epoll_scheduler::shutdown()
224   { 224   {
HITCBC 225   366 shutdown_drain(); 225   366 shutdown_drain();
226   226  
HITCBC 227   366 if (event_fd_ >= 0) 227   366 if (event_fd_ >= 0)
HITCBC 228   366 interrupt_reactor(); 228   366 interrupt_reactor();
HITCBC 229   366 } 229   366 }
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   4948 epoll_scheduler::register_descriptor(int fd, reactor_descriptor_state* desc) const 244   4291 epoll_scheduler::register_descriptor(int fd, reactor_descriptor_state* desc) const
245   { 245   {
HITCBC 246   4948 epoll_event ev{}; 246   4291 epoll_event ev{};
HITCBC 247   4948 ev.events = EPOLLIN | EPOLLOUT | EPOLLET | EPOLLERR | EPOLLHUP; 247   4291 ev.events = EPOLLIN | EPOLLOUT | EPOLLET | EPOLLERR | EPOLLHUP;
HITCBC 248   4948 ev.data.ptr = desc; 248   4291 ev.data.ptr = desc;
249   249  
HITCBC 250   4948 if (::epoll_ctl(epoll_fd_, EPOLL_CTL_ADD, fd, &ev) < 0) 250   4291 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   4948 desc->registered_events = ev.events; 253   4291 desc->registered_events = ev.events;
HITCBC 254   4948 desc->fd = fd; 254   4291 desc->fd = fd;
HITCBC 255   4948 desc->scheduler_ = this; 255   4291 desc->scheduler_ = this;
HITCBC 256   4948 desc->mutex.set_enabled(!single_threaded_); 256   4291 desc->mutex.set_enabled(!single_threaded_);
HITCBC 257   4948 desc->ready_events_.store(0, std::memory_order_relaxed); 257   4291 desc->ready_events_.store(0, std::memory_order_relaxed);
258   258  
HITCBC 259   4948 conditionally_enabled_mutex::scoped_lock lock(desc->mutex); 259   4291 conditionally_enabled_mutex::scoped_lock lock(desc->mutex);
HITCBC 260   4948 desc->impl_ref_.reset(); 260   4291 desc->impl_ref_.reset();
HITCBC 261   4948 desc->read_ready = false; 261   4291 desc->read_ready = false;
HITCBC 262   4948 desc->write_ready = false; 262   4291 desc->write_ready = false;
HITCBC 263   4948 } 263   4291 }
264   264  
265   inline void 265   inline void
HITCBC 266   4948 epoll_scheduler::deregister_descriptor(int fd) const 266   4291 epoll_scheduler::deregister_descriptor(int fd) const
267   { 267   {
HITCBC 268   4948 ::epoll_ctl(epoll_fd_, EPOLL_CTL_DEL, fd, nullptr); 268   4291 ::epoll_ctl(epoll_fd_, EPOLL_CTL_DEL, fd, nullptr);
HITCBC 269   4948 } 269   4291 }
270   270  
271   inline void 271   inline void
HITCBC 272   3276 epoll_scheduler::interrupt_reactor() const 272   2942 epoll_scheduler::interrupt_reactor() const
273   { 273   {
HITCBC 274   3276 bool expected = false; 274   2942 bool expected = false;
HITCBC 275   3276 if (eventfd_armed_.compare_exchange_strong( 275   2942 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   3043 std::uint64_t val = 1; 279   2713 std::uint64_t val = 1;
HITCBC 280   3043 [[maybe_unused]] auto r = ::write(event_fd_, &val, sizeof(val)); 280   2713 [[maybe_unused]] auto r = ::write(event_fd_, &val, sizeof(val));
281   } 281   }
HITCBC 282   3276 } 282   2942 }
283   283  
284   inline void 284   inline void
HITCBC 285   5156 epoll_scheduler::update_timerfd() const 285   4491 epoll_scheduler::update_timerfd() const
286   { 286   {
HITCBC 287   5156 auto nearest = timer_svc_->nearest_expiry(); 287   4491 auto nearest = timer_svc_->nearest_expiry();
288   288  
HITCBC 289   5156 itimerspec ts{}; 289   4491 itimerspec ts{};
HITCBC 290   5156 int flags = 0; 290   4491 int flags = 0;
291   291  
HITCBC 292   5156 if (nearest == timer_service::time_point::max()) 292   4491 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   5101 auto now = std::chrono::steady_clock::now(); 298   4435 auto now = std::chrono::steady_clock::now();
HITCBC 299   5101 if (nearest <= now) 299   4435 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   397 ts.it_value.tv_nsec = 1; 302   492 ts.it_value.tv_nsec = 1;
303   } 303   }
304   else 304   else
305   { 305   {
HITCBC 306   4704 auto nsec = std::chrono::duration_cast<std::chrono::nanoseconds>( 306   3943 auto nsec = std::chrono::duration_cast<std::chrono::nanoseconds>(
HITCBC 307   4704 nearest - now) 307   3943 nearest - now)
HITCBC 308   4704 .count(); 308   3943 .count();
HITCBC 309   4704 ts.it_value.tv_sec = nsec / 1000000000; 309   3943 ts.it_value.tv_sec = nsec / 1000000000;
HITCBC 310   4704 ts.it_value.tv_nsec = nsec % 1000000000; 310   3943 ts.it_value.tv_nsec = nsec % 1000000000;
HITCBC 311   4704 if (ts.it_value.tv_sec == 0 && ts.it_value.tv_nsec == 0) 311   3943 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   5156 if (::timerfd_settime(timer_fd_, flags, &ts, nullptr) < 0) 316   4491 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   5156 } 318   4491 }
319   319  
320   inline void 320   inline void
HITCBC 321   29546 epoll_scheduler::run_task( 321   34613 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   29546 if (task_interrupted_) 325   34613 if (task_interrupted_)
HITCBC 326   22614 timeout_ms = 0; 326   28785 timeout_ms = 0;
HITCBC 327   6932 else if (timeout_us < 0) 327   5828 else if (timeout_us < 0)
HITCBC 328   6924 timeout_ms = -1; 328   5820 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   29546 if (lock.owns_lock()) 332   34613 if (lock.owns_lock())
HITCBC 333   6932 lock.unlock(); 333   5828 lock.unlock();
334   334  
HITCBC 335   29546 task_cleanup on_exit{this, &lock, ctx}; 335   34613 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   29546 if (timerfd_stale_.exchange(false, std::memory_order_acquire)) 338   34613 if (timerfd_stale_.exchange(false, std::memory_order_acquire))
HITCBC 339   2576 update_timerfd(); 339   2244 update_timerfd();
340   340  
HITCBC 341   29546 int nfds = ::epoll_wait( 341   34613 int nfds = ::epoll_wait(
342   epoll_fd_, event_buffer_.data(), 342   epoll_fd_, event_buffer_.data(),
HITCBC 343   29546 static_cast<int>(event_buffer_.size()), timeout_ms); 343   34613 static_cast<int>(event_buffer_.size()), timeout_ms);
344   344  
HITCBC 345   29546 if (nfds < 0 && errno != EINTR) 345   34613 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   29546 bool check_timers = false; 348   34613 bool check_timers = false;
HITCBC 349   29546 op_queue local_ops; 349   34613 op_queue local_ops;
350   350  
HITCBC 351   69671 for (int i = 0; i < nfds; ++i) 351   80096 for (int i = 0; i < nfds; ++i)
352   { 352   {
HITCBC 353   40125 if (event_buffer_[i].data.ptr == nullptr) 353   45483 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   2677 [[maybe_unused]] auto r = ::read(event_fd_, &val, sizeof(val)); 357   2347 [[maybe_unused]] auto r = ::read(event_fd_, &val, sizeof(val));
HITCBC 358   2677 eventfd_armed_.store(false, std::memory_order_relaxed); 358   2347 eventfd_armed_.store(false, std::memory_order_relaxed);
HITCBC 359   2677 continue; 359   2347 continue;
HITCBC 360   2677 } 360   2347 }
361   361  
HITCBC 362   37448 if (event_buffer_[i].data.ptr == &timer_fd_) 362   43136 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   2580 ::read(timer_fd_, &expirations, sizeof(expirations)); 367   2247 ::read(timer_fd_, &expirations, sizeof(expirations));
HITCBC 368   2580 check_timers = true; 368   2247 check_timers = true;
HITCBC 369   2580 continue; 369   2247 continue;
HITCBC 370   2580 } 370   2247 }
371   371  
372   auto* desc = 372   auto* desc =
HITCBC 373   34868 static_cast<reactor_descriptor_state*>(event_buffer_[i].data.ptr); 373   40889 static_cast<reactor_descriptor_state*>(event_buffer_[i].data.ptr);
HITCBC 374   34868 desc->add_ready_events(event_buffer_[i].events); 374   40889 desc->add_ready_events(event_buffer_[i].events);
375   375  
HITCBC 376   34868 bool expected = false; 376   40889 bool expected = false;
HITCBC 377   34868 if (desc->is_enqueued_.compare_exchange_strong( 377   40889 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   34868 local_ops.push(desc); 381   40889 local_ops.push(desc);
382   } 382   }
383   } 383   }
384   384  
HITCBC 385   29546 if (check_timers) 385   34613 if (check_timers)
386   { 386   {
HITCBC 387   2580 timer_svc_->process_expired(); 387   2247 timer_svc_->process_expired();
HITCBC 388   2580 update_timerfd(); 388   2247 update_timerfd();
389   } 389   }
390   390  
HITCBC 391   29546 lock.lock(); 391   34613 lock.lock();
392   392  
HITCBC 393   29546 if (!local_ops.empty()) 393   34613 if (!local_ops.empty())
HITCBC 394   22080 completed_ops_.splice(local_ops); 394   28252 completed_ops_.splice(local_ops);
HITCBC 395   29546 } 395   34613 }
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