From 3c21a6facc53a7d3614619741bd3139193566e0d Mon Sep 17 00:00:00 2001
From: Timo Heister <timo.heister@gmail.com>
Date: Mon, 18 Jan 2016 22:13:40 -0500
Subject: [PATCH] add failing test

---
 tests/multigrid/transfer_prebuilt_04.cc       | 99 +++++++++++++++++++
 .../transfer_prebuilt_04.mpirun=2.output      | 11 +++
 .../transfer_prebuilt_04.mpirun=3.output      | 11 +++
 3 files changed, 121 insertions(+)
 create mode 100644 tests/multigrid/transfer_prebuilt_04.cc
 create mode 100644 tests/multigrid/transfer_prebuilt_04.mpirun=2.output
 create mode 100644 tests/multigrid/transfer_prebuilt_04.mpirun=3.output

diff --git a/tests/multigrid/transfer_prebuilt_04.cc b/tests/multigrid/transfer_prebuilt_04.cc
new file mode 100644
index 0000000000..8f4d34548b
--- /dev/null
+++ b/tests/multigrid/transfer_prebuilt_04.cc
@@ -0,0 +1,99 @@
+// ---------------------------------------------------------------------
+//
+// Copyright (C) 2000 - 2015 by the deal.II authors
+//
+// This file is part of the deal.II library.
+//
+// The deal.II library is free software; you can use it, redistribute
+// it, and/or modify it under the terms of the GNU Lesser General
+// Public License as published by the Free Software Foundation; either
+// version 2.1 of the License, or (at your option) any later version.
+// The full text of the license can be found in the file LICENSE at
+// the top level of the deal.II distribution.
+//
+// ---------------------------------------------------------------------
+
+
+// Deadlock reported by Kronbichler (github
+// https://github.com/dealii/dealii/issues/2051) with 3 processes
+// in MgTransferPrebuilt
+
+
+#include "../tests.h"
+#include <deal.II/base/logstream.h>
+#include <deal.II/lac/parallel_vector.h>
+#include <deal.II/dofs/dof_tools.h>
+#include <deal.II/distributed/tria.h>
+#include <deal.II/grid/grid_generator.h>
+#include <deal.II/fe/fe_q.h>
+#include <deal.II/multigrid/mg_transfer.h>
+#include <deal.II/grid/grid_out.h>
+
+
+template <int dim>
+void check()
+{
+  FE_Q<dim> fe(1);
+
+  parallel::distributed::Triangulation<dim>
+  tr(MPI_COMM_WORLD,
+     Triangulation<dim>::limit_level_difference_at_vertices,
+     parallel::distributed::Triangulation<dim>::construct_multigrid_hierarchy);
+  GridGenerator::subdivided_hyper_cube (tr, 3);
+  for (unsigned int cycle=0; cycle<(dim == 2 ? 10 : 7); ++cycle)
+    {
+      // adaptive refinement into a circle
+      for (typename Triangulation<dim>::active_cell_iterator cell=tr.begin_active(); cell != tr.end(); ++cell)
+        if (cell->is_locally_owned() &&
+            cell->vertex(0).norm() < 1e-10)
+          cell->set_refine_flag();
+      tr.execute_coarsening_and_refinement();
+
+      deallog << "no. cells: " << tr.n_global_active_cells() << " on "
+              << tr.n_global_levels() << " levels" << std::endl;
+
+      DoFHandler<dim> mgdof(tr);
+      mgdof.distribute_dofs(fe);
+      mgdof.distribute_mg_dofs(fe);
+
+      ConstraintMatrix hanging_node_constraints;
+      IndexSet relevant_dofs;
+      DoFTools::extract_locally_relevant_dofs(mgdof, relevant_dofs);
+      hanging_node_constraints.reinit(relevant_dofs);
+      DoFTools::make_hanging_node_constraints(mgdof, hanging_node_constraints);
+      hanging_node_constraints.close();
+
+      MGConstrainedDoFs mg_constrained_dofs;
+      ZeroFunction<dim> zero_function;
+      typename FunctionMap<dim>::type dirichlet_boundary;
+      dirichlet_boundary[0] = &zero_function;
+      mg_constrained_dofs.initialize(mgdof, dirichlet_boundary);
+
+      unsigned int myid = Utilities::MPI::this_mpi_process (MPI_COMM_WORLD);
+
+      if (0)
+        {
+          std::ofstream grid_output (("out"+Utilities::to_string(myid)+".svg").c_str());
+          GridOut grid_out;
+          GridOutFlags::Svg flags;
+          flags.label_level_subdomain_id = true;
+          flags.coloring = GridOutFlags::Svg::level_subdomain_id;
+          flags.convert_level_number_to_height = true;
+          grid_out.set_flags(flags);
+
+          grid_out.write_svg (tr, grid_output);
+        }
+
+      MGTransferPrebuilt<parallel::distributed::Vector<double> >
+      transfer_ref(hanging_node_constraints, mg_constrained_dofs);
+      transfer_ref.build_matrices(mgdof);
+    }
+}
+
+int main(int argc, char **argv)
+{
+  Utilities::MPI::MPI_InitFinalize mpi(argc, argv);
+  mpi_initlog();
+
+  check<2>();
+}
diff --git a/tests/multigrid/transfer_prebuilt_04.mpirun=2.output b/tests/multigrid/transfer_prebuilt_04.mpirun=2.output
new file mode 100644
index 0000000000..2df36ef18f
--- /dev/null
+++ b/tests/multigrid/transfer_prebuilt_04.mpirun=2.output
@@ -0,0 +1,11 @@
+
+DEAL::no. cells: 12 on 2 levels
+DEAL::no. cells: 15 on 3 levels
+DEAL::no. cells: 18 on 4 levels
+DEAL::no. cells: 21 on 5 levels
+DEAL::no. cells: 24 on 6 levels
+DEAL::no. cells: 27 on 7 levels
+DEAL::no. cells: 30 on 8 levels
+DEAL::no. cells: 33 on 9 levels
+DEAL::no. cells: 36 on 10 levels
+DEAL::no. cells: 39 on 11 levels
diff --git a/tests/multigrid/transfer_prebuilt_04.mpirun=3.output b/tests/multigrid/transfer_prebuilt_04.mpirun=3.output
new file mode 100644
index 0000000000..2df36ef18f
--- /dev/null
+++ b/tests/multigrid/transfer_prebuilt_04.mpirun=3.output
@@ -0,0 +1,11 @@
+
+DEAL::no. cells: 12 on 2 levels
+DEAL::no. cells: 15 on 3 levels
+DEAL::no. cells: 18 on 4 levels
+DEAL::no. cells: 21 on 5 levels
+DEAL::no. cells: 24 on 6 levels
+DEAL::no. cells: 27 on 7 levels
+DEAL::no. cells: 30 on 8 levels
+DEAL::no. cells: 33 on 9 levels
+DEAL::no. cells: 36 on 10 levels
+DEAL::no. cells: 39 on 11 levels
-- 
2.39.5