X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/blobdiff_plain/b8df87e176f27b25534f27d7e240defa32ca35bc..4d58af5e9f29128ea5d5cbb677884eae5ba1bf81:/src/kernel/activity/MutexImpl.cpp

diff --git a/src/kernel/activity/MutexImpl.cpp b/src/kernel/activity/MutexImpl.cpp
index cc82ce65f2..c981c3ee76 100644
--- a/src/kernel/activity/MutexImpl.cpp
+++ b/src/kernel/activity/MutexImpl.cpp
@@ -1,134 +1,144 @@
-/* Copyright (c) 2007-2019. The SimGrid Team. All rights reserved.          */
+/* Copyright (c) 2007-2023. 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/kernel/activity/MutexImpl.hpp"
-#include "src/kernel/activity/SynchroRaw.hpp"
-#include "src/simix/smx_synchro_private.hpp"
+#include "src/kernel/activity/Synchro.hpp"
 
-XBT_LOG_NEW_DEFAULT_SUBCATEGORY(simix_mutex, simix_synchro, "Mutex kernel-space implementation");
+XBT_LOG_NEW_DEFAULT_SUBCATEGORY(ker_mutex, ker_synchro, "Mutex kernel-space implementation");
 
-namespace simgrid {
-namespace kernel {
-namespace activity {
+namespace simgrid::kernel::activity {
 
-MutexImpl::MutexImpl() : piface_(this)
+/* -------- Acquisition -------- */
+
+bool MutexAcquisitionImpl::test(actor::ActorImpl*)
 {
-  XBT_IN("(%p)", this);
-  XBT_OUT();
+  return mutex_->owner_ == issuer_;
 }
+void MutexAcquisitionImpl::wait_for(actor::ActorImpl* issuer, double timeout)
+{
+  xbt_assert(mutex_->owner_ != nullptr); // it was locked either by someone else or by me during the lock_async
+  xbt_assert(issuer == issuer_, "Cannot wait on acquisitions created by another actor (id %ld)", issuer_->get_pid());
+  xbt_assert(timeout < 0, "Timeouts on mutex acquisitions are not implemented yet.");
 
-MutexImpl::~MutexImpl()
+  this->register_simcall(&issuer_->simcall_); // Block on that acquisition
+
+  if (mutex_->get_owner() == issuer_) { // I'm the owner
+    finish();
+  } else {
+    // Already in the queue
+  }
+}
+
+void MutexAcquisitionImpl::finish()
 {
-  XBT_IN("(%p)", this);
-  XBT_OUT();
+  xbt_assert(simcalls_.size() == 1, "Unexpected number of simcalls waiting: %zu", simcalls_.size());
+  actor::Simcall* simcall = simcalls_.front();
+  simcalls_.pop_front();
+
+  simcall->issuer_->waiting_synchro_ = nullptr;
+  simcall->issuer_->simcall_answer();
 }
 
-void MutexImpl::lock(smx_actor_t issuer)
+/* -------- Mutex -------- */
+
+unsigned MutexImpl::next_id_ = 0;
+
+MutexAcquisitionImplPtr MutexImpl::lock_async(actor::ActorImpl* issuer)
 {
-  XBT_IN("(%p; %p)", this, issuer);
-  /* FIXME: check where to validate the arguments */
-  smx_activity_t synchro = nullptr;
-
-  if (this->locked) {
-    /* FIXME: check if the host is active ? */
-    /* Somebody using the mutex, use a synchronization to get host failures */
-    synchro = SIMIX_synchro_wait(issuer->host_, -1);
-    synchro->simcalls_.push_back(&issuer->simcall);
-    issuer->waiting_synchro = synchro;
-    this->sleeping.push_back(*issuer);
-  } else {
-    /* mutex free */
-    this->locked = true;
-    this->owner  = issuer;
-    SIMIX_simcall_answer(&issuer->simcall);
+  /* If the mutex is recursive */
+  if (is_recursive_) {
+    if (owner_ == issuer) {
+      recursive_depth++;
+      auto res = MutexAcquisitionImplPtr(new kernel::activity::MutexAcquisitionImpl(issuer, this), true);
+      res->grant();
+      return res;
+    } else if (owner_ == nullptr) { // Free
+      owner_          = issuer;
+      recursive_depth = 1;
+      auto res        = MutexAcquisitionImplPtr(new kernel::activity::MutexAcquisitionImpl(issuer, this), true);
+      res->grant();
+      return res;
+    }
+
+    for (auto acq : ongoing_acquisitions_)
+      if (acq->get_issuer() == issuer) {
+        acq->recursive_depth_++;
+        return acq;
+      }
+
+    // Not yet in the ongoing acquisition list. Get in there
+    auto res = MutexAcquisitionImplPtr(new kernel::activity::MutexAcquisitionImpl(issuer, this), true);
+    ongoing_acquisitions_.push_back(res);
+    return res;
   }
-  XBT_OUT();
+
+  // None-recursive mutex
+  auto res = MutexAcquisitionImplPtr(new kernel::activity::MutexAcquisitionImpl(issuer, this), true);
+  if (owner_ == nullptr) { // Lock is free, take it
+    owner_  = issuer;
+    recursive_depth = 1;
+    res->grant();
+  } else { // Somebody is using the mutex; register the acquisition
+    ongoing_acquisitions_.push_back(res);
+  }
+  return res;
 }
 
-/** Tries to lock the mutex for a process
+/** Tries to lock the mutex for a actor
  *
- * @param  issuer  the process that tries to acquire the mutex
+ * @param  issuer  the actor that tries to acquire the mutex
  * @return whether we managed to lock the mutex
  */
-bool MutexImpl::try_lock(smx_actor_t issuer)
+bool MutexImpl::try_lock(actor::ActorImpl* issuer)
 {
-  XBT_IN("(%p, %p)", this, issuer);
-  if (this->locked) {
-    XBT_OUT();
-    return false;
+  if (owner_ == issuer && is_recursive_) {
+    recursive_depth++;
+    return true;
   }
+  if (owner_ != nullptr)
+    return false;
 
-  this->locked = true;
-  this->owner  = issuer;
-  XBT_OUT();
+  owner_ = issuer;
   return true;
 }
 
-/** Unlock a mutex for a process
+/** Unlock a mutex for a actor
  *
- * Unlocks the mutex and gives it to a process waiting for it.
+ * Unlocks the mutex and gives it to a actor waiting for it.
  * If the unlocker is not the owner of the mutex nothing happens.
- * If there are no process waiting, it sets the mutex as free.
+ * If there are no actor waiting, it sets the mutex as free.
  */
-void MutexImpl::unlock(smx_actor_t issuer)
+void MutexImpl::unlock(actor::ActorImpl* issuer)
 {
   XBT_IN("(%p, %p)", this, issuer);
-  if (not this->locked)
-    THROWF(mismatch_error, 0, "Cannot release that mutex: it was not locked.");
-
-  /* If the mutex is not owned by the issuer, that's not good */
-  if (issuer != this->owner)
-    THROWF(mismatch_error, 0, "Cannot release that mutex: it was locked by %s (pid:%ld), not by you.",
-           this->owner->get_cname(), this->owner->pid_);
-
-  if (not this->sleeping.empty()) {
-    /*process to wake up */
-    smx_actor_t p = &this->sleeping.front();
-    this->sleeping.pop_front();
-    p->waiting_synchro = nullptr;
-    this->owner        = p;
-    SIMIX_simcall_answer(&p->simcall);
-  } else {
-    /* nobody to wake up */
-    this->locked = false;
-    this->owner  = nullptr;
-  }
-  XBT_OUT();
-}
-}
-}
-}
+  xbt_assert(issuer == owner_, "Cannot release that mutex: you're not the owner. %s is (pid:%ld).",
+             owner_ != nullptr ? owner_->get_cname() : "(nobody)", owner_ != nullptr ? owner_->get_pid() : -1);
 
-/** Increase the refcount for this mutex */
-smx_mutex_t SIMIX_mutex_ref(smx_mutex_t mutex)
-{
-  if (mutex != nullptr)
-    intrusive_ptr_add_ref(mutex);
-  return mutex;
-}
-
-/** Decrease the refcount for this mutex */
-void SIMIX_mutex_unref(smx_mutex_t mutex)
-{
-  if (mutex != nullptr)
-    intrusive_ptr_release(mutex);
-}
+  if (is_recursive_) {
+    recursive_depth--;
+    if (recursive_depth > 0) // Still owning the lock
+      return;
+  }
 
-// Simcall handlers:
+  if (not ongoing_acquisitions_.empty()) {
+    /* Give the ownership to the first waiting actor */
+    auto acq = ongoing_acquisitions_.front();
+    ongoing_acquisitions_.pop_front();
 
-void simcall_HANDLER_mutex_lock(smx_simcall_t simcall, smx_mutex_t mutex)
-{
-  mutex->lock(simcall->issuer);
-}
+    owner_ = acq->get_issuer();
+    acq->grant();
+    recursive_depth = acq->recursive_depth_;
+    if (acq == owner_->waiting_synchro_)
+      acq->finish();
+    // else, the issuer is not blocked on this acquisition so no need to release it
 
-int simcall_HANDLER_mutex_trylock(smx_simcall_t simcall, smx_mutex_t mutex)
-{
-  return mutex->try_lock(simcall->issuer);
+  } else {
+    /* nobody to wake up */
+    owner_  = nullptr;
+  }
+  XBT_OUT();
 }
 
-void simcall_HANDLER_mutex_unlock(smx_simcall_t simcall, smx_mutex_t mutex)
-{
-  mutex->unlock(simcall->issuer);
-}
+} // namespace simgrid::kernel::activity