X-Git-Url: http://bilbo.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/blobdiff_plain/361258ab0fbf44b907a966b0ad83c46fe7353925..6e80e277a2e65be7caefd0e04e4954c4fc26c2d8:/src/s4u/s4u_Semaphore.cpp

diff --git a/src/s4u/s4u_Semaphore.cpp b/src/s4u/s4u_Semaphore.cpp
index 191094aeb9..7144363c51 100644
--- a/src/s4u/s4u_Semaphore.cpp
+++ b/src/s4u/s4u_Semaphore.cpp
@@ -1,56 +1,122 @@
-/* Copyright (c) 2006-201. The SimGrid Team. All rights reserved.          */
+/* Copyright (c) 2018-2023. The SimGrid Team. All rights reserved.          */
 
 /* This program is free software; you can redistribute it and/or modify it
  * under the terms of the license (GNU LGPL) which comes with this package. */
 
-#include "src/msg/msg_private.hpp"
-#include "src/simix/smx_synchro_private.hpp"
-#include "xbt/log.h"
+#include <simgrid/modelchecker.h>
+#include <simgrid/s4u/Semaphore.hpp>
+#include <simgrid/semaphore.h>
 
-#include "simgrid/s4u/Semaphore.hpp"
+#include "src/kernel/activity/SemaphoreImpl.hpp"
+#include "src/kernel/actor/SynchroObserver.hpp"
+#include "src/mc/mc_replay.hpp"
 
-namespace simgrid {
-namespace s4u {
+namespace simgrid::s4u {
 
-Semaphore::Semaphore(unsigned int initial_capacity)
+SemaphorePtr Semaphore::create(unsigned int initial_capacity)
 {
-    sem_ = simgrid::simix::simcall([initial_capacity] { return SIMIX_sem_init(initial_capacity); });
+  auto* sem = new kernel::activity::SemaphoreImpl(initial_capacity);
+  return SemaphorePtr(&sem->sem(), false);
 }
 
-Semaphore::~Semaphore()
+void Semaphore::acquire()
 {
-    SIMIX_sem_destroy(sem_);
+  acquire_timeout(-1);
 }
 
-SemaphorePtr Semaphore::create(unsigned int initial_capacity)
+bool Semaphore::acquire_timeout(double timeout)
 {
-    return SemaphorePtr(new Semaphore(initial_capacity));
+  kernel::actor::ActorImpl* issuer = kernel::actor::ActorImpl::self();
+
+  if (MC_is_active() || MC_record_replay_is_active()) { // Split in 2 simcalls for transition persistency
+    kernel::actor::SemaphoreObserver lock_observer{issuer, mc::Transition::Type::SEM_ASYNC_LOCK, pimpl_};
+    auto acquisition =
+        kernel::actor::simcall_answered([issuer, this] { return pimpl_->acquire_async(issuer); }, &lock_observer);
+
+    kernel::actor::SemaphoreAcquisitionObserver wait_observer{issuer, mc::Transition::Type::SEM_WAIT, acquisition.get(),
+                                                              timeout};
+    return kernel::actor::simcall_blocking([issuer, acquisition, timeout] { acquisition->wait_for(issuer, timeout); },
+                                           &wait_observer);
+
+  } else { // Do it in one simcall only and without observer
+    kernel::actor::SemaphoreAcquisitionObserver observer{issuer, mc::Transition::Type::SEM_WAIT, nullptr, timeout};
+    return kernel::actor::simcall_blocking(
+        [this, issuer, timeout] { pimpl_->acquire_async(issuer)->wait_for(issuer, timeout); }, &observer);
+  }
 }
 
-void Semaphore::acquire()
+void Semaphore::release()
 {
-    simcall_sem_acquire(sem_);
+  kernel::actor::ActorImpl* issuer = kernel::actor::ActorImpl::self();
+  kernel::actor::SemaphoreObserver observer{issuer, mc::Transition::Type::SEM_UNLOCK, pimpl_};
+
+  kernel::actor::simcall_answered([this] { pimpl_->release(); }, &observer);
 }
 
-void Semaphore::release()
+int Semaphore::get_capacity() const
 {
-    simgrid::simix::simcall([this] { SIMIX_sem_release(sem_); });
+  return pimpl_->get_capacity();
 }
 
-void intrusive_ptr_add_ref(Semaphore* sem)
+bool Semaphore::would_block() const
 {
-  xbt_assert(sem);
-  sem->refcount_.fetch_add(1, std::memory_order_relaxed);
+  return pimpl_->would_block();
 }
 
-void intrusive_ptr_release(Semaphore* sem)
+/* refcounting of the intrusive_ptr is delegated to the implementation object */
+void intrusive_ptr_add_ref(const Semaphore* sem)
 {
-  xbt_assert(sem);
-  if (sem->refcount_.fetch_sub(1, std::memory_order_release) == 1) {
-    std::atomic_thread_fence(std::memory_order_acquire);
-    delete sem;
-  }
+  intrusive_ptr_add_ref(sem->pimpl_);
+}
+
+void intrusive_ptr_release(const Semaphore* sem)
+{
+  intrusive_ptr_release(sem->pimpl_);
+}
+
+} // namespace simgrid::s4u
+
+/* **************************** Public C interface *************************** */
+/** @brief creates a semaphore object of the given initial capacity */
+sg_sem_t sg_sem_init(int initial_value)
+{
+  return simgrid::s4u::Semaphore::create(initial_value).detach();
+}
+
+/** @brief locks on a semaphore object */
+void sg_sem_acquire(sg_sem_t sem)
+{
+  sem->acquire();
 }
 
+/** @brief locks on a semaphore object up until the provided timeout expires */
+int sg_sem_acquire_timeout(sg_sem_t sem, double timeout)
+{
+  return sem->acquire_timeout(timeout);
+}
+
+/** @brief releases the semaphore object */
+void sg_sem_release(sg_sem_t sem)
+{
+  sem->release();
 }
+
+int sg_sem_get_capacity(const_sg_sem_t sem)
+{
+  return sem->get_capacity();
+}
+
+void sg_sem_destroy(const_sg_sem_t sem)
+{
+  intrusive_ptr_release(sem);
+}
+
+/** @brief returns a boolean indicating if this semaphore would block at this very specific time
+ *
+ * Note that the returned value may be wrong right after the function call, when you try to use it...
+ * But that's a classical semaphore issue, and SimGrid's semaphore are not different to usual ones here.
+ */
+int sg_sem_would_block(const_sg_sem_t sem)
+{
+  return sem->would_block();
 }