ceph/src/boost/boost/fiber/waker.hpp

   1 #ifndef BOOST_FIBERS_WAKER_H
   2 #define BOOST_FIBERS_WAKER_H
   3
   4 #include <cstddef>
   5
   6 #include <boost/config.hpp>
   7 #include <boost/fiber/detail/config.hpp>
   8 #include <boost/fiber/detail/spinlock.hpp>
   9 #include <boost/intrusive/slist.hpp>
  10
  11 namespace boost {
  12 namespace fibers {
  13
  14 class context;
  15
  16 namespace detail {
  17
  18 typedef intrusive::slist_member_hook<> waker_queue_hook;
  19
  20 } // detail
  21
  22
  23 class BOOST_FIBERS_DECL waker {
  24 private:
  25     context *ctx_{};
  26     size_t epoch_{};
  27
  28 public:
  29     friend class context;
  30
  31     waker() = default;
  32
  33     waker(context * ctx, const size_t epoch)
  34         : ctx_{ ctx }
  35         , epoch_{ epoch }
  36     {}
  37
  38     bool wake() const noexcept;
  39 };
  40
  41
  42 class BOOST_FIBERS_DECL waker_with_hook : public waker {
  43 public:
  44     explicit waker_with_hook(waker && w)
  45         : waker{ std::move(w) }
  46     {}
  47
  48     bool is_linked() const noexcept {
  49         return waker_queue_hook_.is_linked();
  50     }
  51
  52     friend bool
  53     operator==( waker const& lhs, waker const& rhs) noexcept {
  54         return & lhs == & rhs;
  55     }
  56
  57 public:
  58     detail::waker_queue_hook waker_queue_hook_{};
  59 };
  60
  61 namespace detail {
  62     typedef intrusive::slist<
  63             waker_with_hook,
  64             intrusive::member_hook<
  65                 waker_with_hook, detail::waker_queue_hook, & waker_with_hook::waker_queue_hook_ >,
  66             intrusive::constant_time_size< false >,
  67             intrusive::cache_last< true >
  68         >                                               waker_slist_t;
  69 }
  70
  71 class BOOST_FIBERS_DECL wait_queue {
  72 private:
  73     detail::waker_slist_t   slist_{};
  74
  75 public:
  76     void suspend_and_wait( detail::spinlock_lock &, context *);
  77     bool suspend_and_wait_until( detail::spinlock_lock &,
  78                                  context *,
  79                                  std::chrono::steady_clock::time_point const&);
  80     void notify_one();
  81     void notify_all();
  82
  83     bool empty() const;
  84 };
  85
  86 }}
  87
  88 #endif // BOOST_FIBERS_WAKER_H