src/kernel/activity/BarrierImpl.hpp

   1 /* Copyright (c) 2012-2022. The SimGrid Team. All rights reserved.          */
   2
   3 /* This program is free software; you can redistribute it and/or modify it
   4  * under the terms of the license (GNU LGPL) which comes with this package. */
   5
   6 #ifndef SIMGRID_KERNEL_ACTIVITY_BARRIER_HPP
   7 #define SIMGRID_KERNEL_ACTIVITY_BARRIER_HPP
   8
   9 #include "simgrid/s4u/Barrier.hpp"
  10 #include "src/kernel/activity/ActivityImpl.hpp"
  11 #include "src/kernel/actor/ActorImpl.hpp"
  12 #include "src/kernel/actor/SynchroObserver.hpp"
  13 #include "xbt/string.hpp"
  14
  15 namespace simgrid::kernel::activity {
  16 /** Barrier Acquisition: the act / process of acquiring the barrier.
  17  *
  18  * This is the asynchronous activity associated to Barriers. See the doc of MutexImpl for more details on the rationnal.
  19  */
  20 class XBT_PUBLIC BarrierAcquisitionImpl : public ActivityImpl_T<BarrierAcquisitionImpl> {
  21   actor::ActorImpl* issuer_ = nullptr;
  22   BarrierImpl* barrier_     = nullptr;
  23   bool granted_             = false;
  24
  25   friend actor::BarrierObserver;
  26   friend BarrierImpl;
  27
  28 public:
  29   BarrierAcquisitionImpl(actor::ActorImpl* issuer, BarrierImpl* bar) : issuer_(issuer), barrier_(bar) {}
  30   BarrierImplPtr get_barrier() { return barrier_; }
  31   actor::ActorImpl* get_issuer() { return issuer_; }
  32
  33   bool test(actor::ActorImpl* issuer = nullptr) override;
  34   void wait_for(actor::ActorImpl* issuer, double timeout) override;
  35   void post() override
  36   { /*no surf action*/
  37   }
  38   void finish() override;
  39   void set_exception(actor::ActorImpl* issuer) override
  40   { /* nothing to do */
  41   }
  42 };
  43
  44 class XBT_PUBLIC BarrierImpl {
  45   std::atomic_int_fast32_t refcount_{1};
  46   s4u::Barrier piface_;
  47   unsigned int expected_actors_;
  48   std::deque<BarrierAcquisitionImplPtr> ongoing_acquisitions_;
  49   static unsigned next_id_;
  50   unsigned id_ = next_id_++;
  51
  52   friend BarrierAcquisitionImpl;
  53   friend s4u::Barrier;
  54
  55 public:
  56   explicit BarrierImpl(int expected_actors) : piface_(this), expected_actors_(expected_actors) {}
  57   BarrierImpl(BarrierImpl const&) = delete;
  58   BarrierImpl& operator=(BarrierImpl const&) = delete;
  59
  60   BarrierAcquisitionImplPtr acquire_async(actor::ActorImpl* issuer);
  61   unsigned get_id() const { return id_; }
  62
  63   friend void intrusive_ptr_add_ref(BarrierImpl* barrier)
  64   {
  65     XBT_ATTRIB_UNUSED auto previous = barrier->refcount_.fetch_add(1);
  66     xbt_assert(previous != 0);
  67   }
  68
  69   friend void intrusive_ptr_release(BarrierImpl* barrier)
  70   {
  71     if (barrier->refcount_.fetch_sub(1) == 1)
  72       delete barrier;
  73   }
  74
  75   s4u::Barrier& get_iface() { return piface_; }
  76
  77   std::string to_string() const
  78   {
  79     return xbt::string_printf("Barrier %u: %zu of %u", id_, ongoing_acquisitions_.size(), expected_actors_);
  80   }
  81 };
  82 } // namespace simgrid::kernel::activity
  83 #endif