From: turcksin <turcksin@0785d39b-7218-0410-832d-ea1e28bc413d>
Date: Thu, 24 Oct 2013 19:24:26 +0000 (+0000)
Subject: Use Threads::Task in step-13 and step-14.
X-Git-Url: https://gitweb.dealii.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=f82d71bdfc9ddb6e305309f49b7a44ebc3f928f1;p=dealii-svn.git

Use Threads::Task in step-13 and step-14.

git-svn-id: https://svn.dealii.org/trunk@31407 0785d39b-7218-0410-832d-ea1e28bc413d
---

diff --git a/deal.II/examples/step-13/step-13.cc b/deal.II/examples/step-13/step-13.cc
index 17abbb2d79..d7334f3325 100644
--- a/deal.II/examples/step-13/step-13.cc
+++ b/deal.II/examples/step-13/step-13.cc
@@ -28,6 +28,7 @@
 #include <deal.II/base/function.h>
 #include <deal.II/base/logstream.h>
 #include <deal.II/base/table_handler.h>
+#include <deal.II/base/thread_management.h>
 #include <deal.II/base/work_stream.h>
 #include <deal.II/lac/vector.h>
 #include <deal.II/lac/full_matrix.h>
@@ -660,52 +661,6 @@ namespace Step13
         Vector<double>       rhs;
       };
 
-#ifdef DEAL_II_WITH_THREADS
-
-      // Tasks in TBB must be derived from tbb::task and override tbb::task*
-      // execute.
-      // The purpose of HangingNodeTask is to apply execute DoFTools::make_hanging_node_constraints.
-      struct HangingNodeTask : public tbb::task
-      {
-        HangingNodeTask (const DoFHandler<dim> &dof_handler,ConstraintMatrix &hanging_node_constraints) :
-          dof_handler(&dof_handler),
-          hanging_node_constraints(& hanging_node_constraints) {}
-
-        tbb::task* execute()
-        {
-          DoFTools::make_hanging_node_constraints(*dof_handler,*hanging_node_constraints);
-
-          return NULL;
-        }
-
-        const DoFHandler<dim>* dof_handler;
-        ConstraintMatrix* hanging_node_constraints;
-      };                
-
-
-
-      // The purpose of SparsityPatternTask is to create the sparsity pattern.
-      struct SparsityPatternTask : public tbb::task
-      {
-        SparsityPatternTask (const DoFHandler<dim> &dof_handler,SparsityPattern &sparsity_pattern) :
-          dof_handler(&dof_handler),
-          sparsity_pattern(&sparsity_pattern) {}
-
-        tbb::task* execute()
-        {
-          sparsity_pattern->reinit (dof_handler->n_dofs(),
-                                   dof_handler->n_dofs(),
-                                   dof_handler->max_couplings_between_dofs());
-          DoFTools::make_sparsity_pattern (*dof_handler, *sparsity_pattern);
-
-          return NULL;
-        }
-
-        const DoFHandler<dim>* dof_handler;
-        SparsityPattern* sparsity_pattern;
-      };
-
-#endif
 
       // Finally, there is a pair of functions which will be used to assemble
       // the actual system matrix. It calls the virtual function assembling
@@ -972,35 +927,21 @@ namespace Step13
     {
       hanging_node_constraints.clear ();
 
-#ifdef DEAL_II_WITH_THREADS
-      tbb::task_scheduler_init init;
-      // Create an empty task to be the parent of the two tasks that we need.
-      tbb::empty_task* empty_task = new (tbb::task::allocate_root()) tbb::empty_task;
-      // Set the reference count to 3 (number of children+1 because
-      // wati_for_all returns when ref_count is one).
-      empty_task->set_ref_count(3);
-      
-      HangingNodeTask* hanging_node_task = 
-        new (empty_task->allocate_child()) HangingNodeTask(dof_handler,hanging_node_constraints);
-      SparsityPatternTask* sparsity_pattern_task =
-        new (empty_task->allocate_child()) SparsityPatternTask(dof_handler,sparsity_pattern);
-
-      // Spawn the two tasks
-      empty_task->spawn(*hanging_node_task);
-      empty_task->spawn(*sparsity_pattern_task);
-
-      // Wait for children to finish
-      empty_task->wait_for_all();
-      // empty_task must be destroy manually because it does not return.
-      empty_task->destroy(*empty_task);
-#else
-      DoFTools::make_hanging_node_constraints(dof_handler,hanging_node_constraints);
+      void (*mhnc_p) (const DoFHandler<dim> &,
+          ConstraintMatrix &)
+        = &DoFTools::make_hanging_node_constraints;
+
+      // Start a side task then continue on the main thread
+      Threads::Task<> side_task(std_cxx1x::bind(mhnc_p,std_cxx1x::cref(dof_handler),
+            std_cxx1x::ref(hanging_node_constraints)));
 
       sparsity_pattern.reinit (dof_handler.n_dofs(),
                                dof_handler.n_dofs(),
                                dof_handler.max_couplings_between_dofs());
       DoFTools::make_sparsity_pattern (dof_handler, sparsity_pattern);
-#endif
+
+      // Wait for the side task to be done before going further
+      side_task.join();
 
       hanging_node_constraints.close ();
       hanging_node_constraints.condense (sparsity_pattern);
diff --git a/deal.II/examples/step-14/step-14.cc b/deal.II/examples/step-14/step-14.cc
index ec777aa8ce..4d0a881cf6 100644
--- a/deal.II/examples/step-14/step-14.cc
+++ b/deal.II/examples/step-14/step-14.cc
@@ -23,6 +23,7 @@
 #include <deal.II/base/quadrature_lib.h>
 #include <deal.II/base/function.h>
 #include <deal.II/base/logstream.h>
+#include <deal.II/base/thread_management.h>
 #include <deal.II/base/work_stream.h>
 #include <deal.II/lac/vector.h>
 #include <deal.II/lac/full_matrix.h>
@@ -492,46 +493,6 @@ namespace Step14
         Vector<double>       rhs;
       };
 
-#ifdef DEAL_II_WITH_THREADS
-
-      struct HangingNodeTask : public tbb::task
-      {
-        HangingNodeTask (const DoFHandler<dim> &dof_handler,ConstraintMatrix &hanging_node_constraints) :
-          dof_handler(&dof_handler),
-          hanging_node_constraints(& hanging_node_constraints) {}
-
-        tbb::task* execute()
-        {
-          DoFTools::make_hanging_node_constraints(*dof_handler,*hanging_node_constraints);
-
-          return NULL;
-        }
-
-        const DoFHandler<dim>* dof_handler;
-        ConstraintMatrix* hanging_node_constraints;
-      };                
-
-      struct SparsityPatternTask : public tbb::task
-      {
-        SparsityPatternTask (const DoFHandler<dim> &dof_handler,SparsityPattern &sparsity_pattern) :
-          dof_handler(&dof_handler),
-          sparsity_pattern(&sparsity_pattern) {}
-
-        tbb::task* execute()
-        {
-          sparsity_pattern->reinit (dof_handler->n_dofs(),
-                                   dof_handler->n_dofs(),
-                                   dof_handler->max_couplings_between_dofs());
-          DoFTools::make_sparsity_pattern (*dof_handler, *sparsity_pattern);
-
-          return NULL;
-        }
-
-        const DoFHandler<dim>* dof_handler;
-        SparsityPattern* sparsity_pattern;
-      };
-
-#endif
 
       void
       assemble_linear_system (LinearSystem &linear_system);
@@ -722,32 +683,19 @@ namespace Step14
     {
       hanging_node_constraints.clear ();
 
-#ifdef DEAL_II_WITH_THREADS
-      tbb::task_scheduler_init init;
-      // Create an empty task to be the parent of the two tasks that we need.
-      tbb::empty_task* empty_task = new (tbb::task::allocate_root()) tbb::empty_task;
-      // Set the reference count to 3 (number of children+1)
-      empty_task->set_ref_count(3);
-      
-      HangingNodeTask* hanging_node_task = 
-        new (empty_task->allocate_child()) HangingNodeTask(dof_handler,hanging_node_constraints);
-      SparsityPatternTask* sparsity_pattern_task =
-        new (empty_task->allocate_child()) SparsityPatternTask(dof_handler,sparsity_pattern);
-
-      empty_task->spawn(*hanging_node_task);
-      empty_task->spawn(*sparsity_pattern_task);
+      void (*mhnc_p) (const DoFHandler<dim> &,
+          ConstraintMatrix &)
+        = &DoFTools::make_hanging_node_constraints;
 
-      // Wait for children to finish
-      empty_task->wait_for_all();
-      empty_task->destroy(*empty_task);
-#else
-      DoFTools::make_hanging_node_constraints(dof_handler,hanging_node_constraints);
+      Threads::Task<> side_task(std_cxx1x::bind(mhnc_p,std_cxx1x::cref(dof_handler),
+            std_cxx1x::ref(hanging_node_constraints)));
 
       sparsity_pattern.reinit (dof_handler.n_dofs(),
-                               dof_handler.n_dofs(),
-                               dof_handler.max_couplings_between_dofs());
+                                dof_handler.n_dofs(),
+                                dof_handler.max_couplings_between_dofs());
       DoFTools::make_sparsity_pattern (dof_handler, sparsity_pattern);
-#endif
+
+      side_task.join();
 
       hanging_node_constraints.close ();
       hanging_node_constraints.condense (sparsity_pattern);
@@ -2180,12 +2128,12 @@ namespace Step14
     void
     WeightedResidual<dim>::solve_problem ()
     {
-      Threads::ThreadGroup<> threads;
-      threads += Threads::new_thread (&WeightedResidual<dim>::solve_primal_problem,
-                                      *this);
-      threads += Threads::new_thread (&WeightedResidual<dim>::solve_dual_problem,
-                                      *this);
-      threads.join_all ();
+      Threads::TaskGroup<> tasks;
+      tasks += Threads::Task<> (std_cxx1x::bind(&WeightedResidual<dim>::solve_primal_problem,
+            std_cxx1x::ref(*this)));
+      tasks += Threads::Task<> (std_cxx1x::bind(&WeightedResidual<dim>::solve_dual_problem,
+            std_cxx1x::ref(*this)));
+      tasks.join_all();
     }