From 891abf1a3579d0e378a6e1b3426e5c34b23a58ad Mon Sep 17 00:00:00 2001
From: Gabriel Corona <gabriel.corona@loria.fr>
Date: Tue, 14 Jun 2016 13:26:58 +0200
Subject: [PATCH] [simix] Add refcount to Process

---
 src/simix/smx_process.cpp       | 14 +++++++++-----
 src/simix/smx_process_private.h | 19 +++++++++++++++++++
 2 files changed, 28 insertions(+), 5 deletions(-)

diff --git a/src/simix/smx_process.cpp b/src/simix/smx_process.cpp
index 1eb504d23d..836d2d0ae8 100644
--- a/src/simix/smx_process.cpp
+++ b/src/simix/smx_process.cpp
@@ -126,17 +126,21 @@ void SIMIX_process_empty_trash(void)
 
   while ((process = (smx_process_t) xbt_swag_extract(simix_global->process_to_destroy))) {
     XBT_DEBUG("Getting rid of %p",process);
-    delete process->context;
-    xbt_dict_free(&process->properties);
-    xbt_fifo_free(process->comms);
-    xbt_dynar_free(&process->on_exit);
-    delete process;
+    intrusive_ptr_release(process);
   }
 }
 
 namespace simgrid {
 namespace simix {
 
+Process::~Process()
+{
+  delete this->context;
+  xbt_dict_free(&this->properties);
+  xbt_fifo_free(this->comms);
+  xbt_dynar_free(&this->on_exit);
+}
+
 void create_maestro(std::function<void()> code)
 {
   smx_process_t maestro = nullptr;
diff --git a/src/simix/smx_process_private.h b/src/simix/smx_process_private.h
index 0a81e9a410..837cc22d8e 100644
--- a/src/simix/smx_process_private.h
+++ b/src/simix/smx_process_private.h
@@ -7,6 +7,7 @@
 #ifndef _SIMIX_PROCESS_PRIVATE_H
 #define _SIMIX_PROCESS_PRIVATE_H
 
+#include <atomic>
 #include <functional>
 #include <string>
 
@@ -68,6 +69,24 @@ public:
   std::function<void()> code;
   smx_timer_t kill_timer = nullptr;
   int segment_index      = 0;    /*Reference to an SMPI process' data segment. Default value is -1 if not in SMPI context*/
+
+  friend void intrusive_ptr_add_ref(Process* process)
+  {
+    auto previous = (process->refcount_)++;
+    xbt_assert(previous != 0);
+    (void) previous;
+  }
+  friend void intrusive_ptr_release(Process* process)
+  {
+    auto count = --(process->refcount_);
+    if (count == 0)
+      delete process;
+  }
+
+  ~Process();
+
+private:
+  std::atomic_int_fast32_t refcount_ { 1 };
 };
 
 }
-- 
2.20.1