Improve named barriers

Introduce dist::barrier as low-level implementation of a named
barrier.

Use it in Carpet::NamedBarrier.

Use the above in almost all barrier calls.

1 files changed, 14 insertions, 1 deletions

diff --git a/Carpet/CarpetLib/src/dist.cc b/Carpet/CarpetLib/src/dist.cc
index 6f8b759d3..dee79d5bf 100644
--- a/Carpet/CarpetLib/src/dist.cc
+++ b/Carpet/CarpetLib/src/dist.cc
@@ -237,6 +237,19 @@ namespace dist {
     MPI_Finalize ();
   }
   
+  void barrier (MPI_Comm const c, int const id, char const *const name)
+  {
+    int const root = 0;
+    unsigned int my_id = dist::rank()==root ? id : id+1;
+    MPI_Bcast (&my_id, 1, MPI_INT, root, c);
+    if (my_id != id) {
+      CCTK_VWarn (CCTK_WARN_ABORT, __LINE__, __FILE__, CCTK_THORNSTRING,
+                  "Wrong id for Barrier \"%s\": expected %ud, found %ud",
+                  name, id, my_id);
+    }
+    MPI_Barrier (c);
+  }
+
   
   
   // Create an MPI datatype from a C datatype description
@@ -412,7 +425,7 @@ namespace dist {
 	      rank, file, line);
     }
     if (barriers) {
-      MPI_Barrier (comm());
+      dist::barrier (comm(), 506877899+line, "CarpetLib::dist::checkpoint");
     }
   }