Reduce the local termination flag from all processors and have DoneMainLoop()

return this global value. This prevents potential deadlocks, especially with
the max_runtime termination condition.


git-svn-id: http://svn.cactuscode.org/arrangements/CactusPUGH/PUGH/trunk@402 b61c5cb5-eaca-4651-9a7a-d64986f99364

1 files changed, 20 insertions, 11 deletions

diff --git a/src/Evolve.c b/src/Evolve.c
index 910ce43..d3b54f5 100644
--- a/src/Evolve.c
+++ b/src/Evolve.c
@@ -187,7 +187,7 @@ int PUGH_Evolve(tFleshConfig *config)
 static int DoneMainLoop (const cGH *GH, CCTK_REAL simulation_time,int iteration)
 {
   int max_iteration_reached, max_simulation_time_reached, max_runtime_reached;
-  int retval;
+  CCTK_INT local, global;
 #ifdef HAVE_TIME_GETTIMEOFDAY
   struct timeval runtime;
   static struct timeval starttime = {0, 0};
@@ -203,8 +203,8 @@ static int DoneMainLoop (const cGH *GH, CCTK_REAL simulation_time,int iteration)
   }
 #endif
 
-  retval = terminate_next || CCTK_TerminationReached (GH);
-  if (! retval && ! CCTK_Equals (terminate, "never"))
+  local = terminate_next || CCTK_TerminationReached (GH);
+  if (! local && ! CCTK_Equals (terminate, "never"))
   {
     max_iteration_reached = iteration >= cctk_itlast;
 
@@ -231,38 +231,47 @@ static int DoneMainLoop (const cGH *GH, CCTK_REAL simulation_time,int iteration)
 
     if (CCTK_Equals (terminate, "iteration"))
     {
-      retval = max_iteration_reached;
+      local = max_iteration_reached;
     }
     else if (CCTK_Equals (terminate, "time"))
     {
-      retval = max_simulation_time_reached;
+      local = max_simulation_time_reached;
     }
     else if (CCTK_Equals (terminate, "runtime"))
     {
-      retval = max_runtime_reached;
+      local = max_runtime_reached;
     }
     else if (CCTK_Equals (terminate, "any"))
     {
-      retval = max_iteration_reached || max_simulation_time_reached ||
+      local = max_iteration_reached || max_simulation_time_reached ||
                max_runtime_reached;
     }
     else if (CCTK_Equals (terminate, "all"))
     {
-      retval = max_iteration_reached && max_simulation_time_reached &&
+      local = max_iteration_reached && max_simulation_time_reached &&
                max_runtime_reached;
     }
     /* the following two conditions are deprecated in BETA14 */
     else if (CCTK_Equals (terminate, "either"))
     {
-      retval = max_iteration_reached || max_simulation_time_reached;
+      local = max_iteration_reached || max_simulation_time_reached;
     }
     else /* if (CCTK_Equals (terminate, "both")) */
     {
-      retval = max_iteration_reached && max_simulation_time_reached;
+      local = max_iteration_reached && max_simulation_time_reached;
     }
   }
 
-  return (retval);
+#ifdef CCTK_MPI
+  /* reduce the local flags from all processors
+     into a single global termination flag */
+  CACTUS_MPI_ERROR (MPI_Allreduce (&local, &global, 1, PUGH_MPI_INT, MPI_LAND,
+                                   PUGH_pGH (GH)->PUGH_COMM_WORLD));
+#else
+  global = local;
+#endif
+
+  return (global);
 }