#2179: Fixed a race condition caused by the double checked locking pa…

…ttern

- test case

ACE/tests/Future_Stress_Test.cpp

@@ -0,0 +1,148 @@
+
+//=============================================================================
+/**
+ *  @file    Future_Stress_Test.cpp
+ *
+ *  This example tests the ACE Future set() and get() operations in 
+ *  multithreaded environment and concurrent access.
+ *
+ *  Usage: Future_Stress_Test [-t <duration in seconds>]   
+ *            [-n <number of threads>]
+ *
+ *  @see https://github.com/DOCGroup/ACE_TAO/issues/2163
+ *
+ *  @author Andres Kruse <[email protected]>
+ */
+//=============================================================================
+
+#include "test_config.h"
+#include <ace/Time_Value.h>
+#include <ace/Countdown_Time.h>
+#include <ace/Future.h>
+#include <ace/Get_Opt.h>
+
+#include <random>
+
+
+#if defined (ACE_HAS_THREADS)
+
+struct Worker_Config
+{
+  int a;
+  int b;
+  int c;
+  ACE_Future<int> result;
+};
+
+void* worker (void* args)
+{
+  Worker_Config* config = static_cast<Worker_Config*>(args);
+  int r = config->a + config->b * config->c;
+  config->result.set(r);
+
+  return 0;
+}
+
+void* runner (void* args)
+{
+  ACE_DEBUG ((LM_DEBUG, ACE_TEXT ("(%t) runner start\n")));      
+
+  std::random_device              rd;
+  std::mt19937                    gen(rd());
+  std::uniform_int_distribution<> dis(1,1000000);  
+  ACE_Time_Value* duration = static_cast<ACE_Time_Value*>(args);
+  ACE_Countdown_Time timer(duration);
+  timer.start();
+  uint64_t runNum = 0;
+  do
+  {
+    if( ++runNum % 5000 == 0 )
+    {
+      ACE_DEBUG ((LM_DEBUG, ACE_TEXT ("(%t) runner iteration %u\n"), runNum));      
+    }
+    ACE_Future<int> result;
+    Worker_Config config;
+    config.a = dis(gen);
+    config.b = dis(gen);
+    config.c = dis(gen);    
+    config.result = result;
+    ACE_hthread_t thread_id;
+    int expected_res = config.a+config.b*config.c;
+    int actual_res = -1;    
+    if (ACE_Thread::spawn((ACE_THR_FUNC)worker,
+                        (void *)&config, THR_NEW_LWP | THR_JOINABLE, 0,
+                        &thread_id) == -1)
+    {
+        ACE_ERROR ((LM_INFO,
+              ACE_TEXT ("worker thread spawn failed\n")));
+    }
+    result.get(actual_res);
+    if( actual_res != expected_res )
+    {
+      // hit the bug...
+      ACE_ERROR ((LM_INFO,
+          ACE_TEXT ("unexpected ACE_Future result\n")));
+      abort(); 
+    } 
+    ACE_THR_FUNC_RETURN status;
+    ACE_Thread::join(thread_id, &status);
+    timer.update();
+  } while( *duration != ACE_Time_Value::zero );
+   ACE_DEBUG ((LM_DEBUG, ACE_TEXT ("(%t) runner done\n"), runNum));        
+
+   return 0;
+}
+
+int
+run_main (int argc, ACE_TCHAR *argv[])
+{
+  ACE_START_TEST (ACE_TEXT ("Future_Stress_Test"));
+
+  ACE_Time_Value duration(5);
+  long n_threads = 5;
+
+  ACE_Get_Opt getopt (argc, argv, ACE_TEXT ("t:n:"));
+  bool valid = true;
+  int c;
+  while ((c = getopt ()) != -1 && valid)
+  {
+  //FUZZ: enable check_for_lack_ACE_OS
+    switch (c)
+    {
+      case 't':
+        duration.set(ACE_OS::atoi (getopt.opt_arg ()));
+        break;
+      case 'n':
+        n_threads = ACE_OS::atoi (getopt.opt_arg ());
+        break;
+      default:
+        ACE_ERROR ((LM_ERROR,
+                    "Usage: Future_Stress_Test [-t <duration in seconds>]"
+                    "\t[-n <number of threads>]\n"));
+        valid = false;
+        break;
+    }
+  }  
+
+  if (valid)
+  {
+    ACE_Thread_Manager::instance ()->spawn_n (n_threads, 
+      ACE_THR_FUNC (runner),
+      (void *) &duration,
+      THR_NEW_LWP | THR_DETACHED);
+
+    ACE_Thread_Manager::instance ()->wait ();
+    ACE_DEBUG ((LM_DEBUG, ACE_TEXT ("(%t) All threads finished, cleanup and exit\n")));   
+  }
+  ACE_END_TEST;
+  return 0;
+}
+
+#else
+int
+run_main (int, ACE_TCHAR *[])
+{
+  ACE_ERROR ((LM_INFO,
+              ACE_TEXT ("threads not supported on this platform\n")));
+}
+#endif /* ACE_HAS_THREADS */

ACE/tests/run_test.lst

@@ -127,6 +127,7 @@ FIFO_Test: !ACE_FOR_TAO
 Framework_Component_Test: !STATIC !nsk
 Future_Set_Test: !nsk !ACE_FOR_TAO
 Future_Test: !nsk !ACE_FOR_TAO
+Future_Stress_Test: !nsk !ACE_FOR_TAO
 Get_Opt_Test
 Handle_Set_Test: !ACE_FOR_TAO
 Hash_Map_Bucket_Iterator_Test

ACE/tests/tests.mpc

@@ -960,6 +960,14 @@ project(Future Set Test) : acetest {
   }
 }
 
+project(Future Stress Test) : acetest {
+  avoids += ace_for_tao
+  exename = Future_Stress_Test
+  Source_Files {
+    Future_Stress_Test.cpp
+  }
+}
+
 project(Get Opt Test) : acetest {
   exename = Get_Opt_Test
   Source_Files {