diff --git a/src/field/communication/UniformPullReductionPackInfo.h b/src/field/communication/UniformPullReductionPackInfo.h
new file mode 100644
index 0000000000000000000000000000000000000000..71ceb7e8e6fba381d5623f80e3ca6f9bb2b8ae47
--- /dev/null
+++ b/src/field/communication/UniformPullReductionPackInfo.h
@@ -0,0 +1,153 @@
+//======================================================================================================================
+//
+// This file is part of waLBerla. waLBerla is free software: you can
+// redistribute it and/or modify it under the terms of the GNU General Public
+// License as published by the Free Software Foundation, either version 3 of
+// the License, or (at your option) any later version.
+//
+// waLBerla is distributed in the hope that it will be useful, but WITHOUT
+// ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+// FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+// for more details.
+//
+// You should have received a copy of the GNU General Public License along
+// with waLBerla (see COPYING.txt). If not, see <http://www.gnu.org/licenses/>.
+//
+//! \file UniformPullReductionPackInfo.h
+//! \ingroup field
+//! \author Tobias Schruff <schruff@iww.rwth-aachen.de>
+//! \author Christoph Rettinger <christoph.rettinger@fau.de>
+//
+//======================================================================================================================
+
+#pragma once
+
+#include "communication/UniformPackInfo.h"
+
+#include "core/debug/Debug.h"
+
+#include "field/GhostLayerField.h"
+
+#include "stencil/Directions.h"
+
+
+namespace walberla {
+namespace field {
+namespace communication {
+
+/**
+ * Data packing/unpacking for ghost layer based communication of a single walberla::field::Field
+ *
+ * \ingroup comm
+ *
+ * template ReduceOperation is e.g. std::plus
+ *
+ * This pack info is used to apply a given reduce operation (e.g. +) to the values in the interior of a ghost layer field
+ * together with the values coming from the sender's ghost layer.
+ */
+template< template<typename> class ReduceOperation, typename GhostLayerField_T >
+class UniformPullReductionPackInfo : public walberla::communication::UniformPackInfo
+{
+public:
+ typedef typename GhostLayerField_T::value_type T;
+
+ UniformPullReductionPackInfo( const BlockDataID & bdID ) : bdID_( bdID ), communicateAllGhostLayers_( true ),
+ numberOfGhostLayers_( 0 ) {}
+
+ UniformPullReductionPackInfo( const BlockDataID & bdID, const uint_t numberOfGhostLayers ) : bdID_( bdID ),
+ communicateAllGhostLayers_( false ), numberOfGhostLayers_( numberOfGhostLayers ) {}
+
+ virtual ~UniformPullReductionPackInfo() {}
+
+ bool constantDataExchange() const { return mpi::BufferSizeTrait<T>::constantSize; }
+ bool threadsafeReceiving() const { return true; }
+
+ void unpackData(IBlock * receiver, stencil::Direction dir, mpi::RecvBuffer & buffer);
+
+ void communicateLocal(const IBlock * sender, IBlock * receiver, stencil::Direction dir);
+
+protected:
+ void packDataImpl(const IBlock * sender, stencil::Direction dir, mpi::SendBuffer & outBuffer) const;
+
+ uint_t numberOfGhostLayersToCommunicate( const GhostLayerField_T * const field ) const;
+
+ const BlockDataID bdID_;
+ bool communicateAllGhostLayers_;
+ uint_t numberOfGhostLayers_;
+ ReduceOperation<T> op_;
+};
+
+
+
+template< template<typename> class ReduceOperation, typename GhostLayerField_T >
+void UniformPullReductionPackInfo<ReduceOperation, GhostLayerField_T>::unpackData( IBlock * receiver, stencil::Direction dir, mpi::RecvBuffer & buffer )
+{
+ GhostLayerField_T * f = receiver->getData< GhostLayerField_T >( bdID_ );
+ WALBERLA_ASSERT_NOT_NULLPTR(f);
+
+ cell_idx_t nrOfGhostLayers = cell_idx_c( numberOfGhostLayersToCommunicate( f ) );
+
+ T buf( 0 );
+ for( auto i = f->beginSliceBeforeGhostLayer( dir, nrOfGhostLayers ); i != f->end(); ++i ) {
+ buffer >> buf;
+ *i = op_( *i, buf );
+ }
+}
+
+
+
+template< template<typename> class ReduceOperation, typename GhostLayerField_T>
+void UniformPullReductionPackInfo<ReduceOperation, GhostLayerField_T>::communicateLocal( const IBlock * sender, IBlock * receiver, stencil::Direction dir )
+{
+ const GhostLayerField_T * sf = sender ->getData< GhostLayerField_T >( bdID_ );
+ GhostLayerField_T * rf = receiver->getData< GhostLayerField_T >( bdID_ );
+
+ WALBERLA_ASSERT_EQUAL(sf->xSize(), rf->xSize());
+ WALBERLA_ASSERT_EQUAL(sf->ySize(), rf->ySize());
+ WALBERLA_ASSERT_EQUAL(sf->zSize(), rf->zSize());
+
+ uint_t nrOfGhostLayers = numberOfGhostLayersToCommunicate( sf );
+ auto srcIter = sf->beginGhostLayerOnly( nrOfGhostLayers, dir );
+ auto dstIter = rf->beginSliceBeforeGhostLayer( stencil::inverseDir[dir], cell_idx_c( nrOfGhostLayers ) );
+
+ while( srcIter != sf->end() ) {
+ *dstIter = op_( *srcIter, *dstIter );
+ ++srcIter;
+ ++dstIter;
+ }
+
+ WALBERLA_ASSERT(srcIter == sf->end() && dstIter == rf->end());
+}
+
+
+
+template< template<typename> class ReduceOperation, typename GhostLayerField_T>
+void UniformPullReductionPackInfo<ReduceOperation, GhostLayerField_T>::packDataImpl( const IBlock * sender, stencil::Direction dir, mpi::SendBuffer & outBuffer ) const
+{
+ const GhostLayerField_T * f = sender->getData< GhostLayerField_T >( bdID_ );
+ WALBERLA_ASSERT_NOT_NULLPTR(f);
+
+ uint_t nrOfGhostLayers = numberOfGhostLayersToCommunicate( f );
+ for( auto i = f->beginGhostLayerOnly( nrOfGhostLayers, dir ); i != f->end(); ++i )
+ outBuffer << *i;
+}
+
+
+
+template< template<typename> class ReduceOperation, typename GhostLayerField_T>
+uint_t UniformPullReductionPackInfo<ReduceOperation, GhostLayerField_T>::numberOfGhostLayersToCommunicate( const GhostLayerField_T * const field ) const
+{
+ if( communicateAllGhostLayers_ )
+ {
+ return field->nrOfGhostLayers();
+ }
+ else
+ {
+ WALBERLA_ASSERT_LESS_EQUAL( numberOfGhostLayers_, field->nrOfGhostLayers() );
+ return numberOfGhostLayers_;
+ }
+}
+
+} // namespace communication
+} // namespace field
+} // namespace walberla
diff --git a/src/field/communication/all.h b/src/field/communication/all.h
index 55782d6e21d8503f473b12a58e10f74ac1d67a8b..a98de888790240fbf77b0454adaf5266ede9ec6b 100644
--- a/src/field/communication/all.h
+++ b/src/field/communication/all.h
@@ -27,3 +27,4 @@
#include "MPIDatatypes.h"
#include "ReducePackInfo.h"
#include "UniformMPIDatatypeInfo.h"
+#include "UniformPullReductionPackInfo.h"
diff --git a/tests/field/communication/FieldPackInfoTest.cpp b/tests/field/communication/FieldPackInfoTest.cpp
index 45f9b00e51e56ada7bf184b095d49c6b88fbe161..d7b94789b8699ffd1b659b9cfdc192ac3fdac4c0 100644
--- a/tests/field/communication/FieldPackInfoTest.cpp
+++ b/tests/field/communication/FieldPackInfoTest.cpp
@@ -16,6 +16,7 @@
//! \file FieldPackInfoTest.cpp
//! \ingroup field
//! \author Martin Bauer <martin.bauer@fau.de>
+//! \author Christoph Rettinger <christoph.rettinger@fau.de>
//! \brief Tests if a Field is correctly packed into buffers
//
//======================================================================================================================
@@ -23,6 +24,7 @@
#include "field/AddToStorage.h"
#include "field/GhostLayerField.h"
#include "field/communication/PackInfo.h"
+#include "field/communication/UniformPullReductionPackInfo.h"
#include "blockforest/Initialization.h"
@@ -85,9 +87,60 @@ void testScalarField( IBlock * block, BlockDataID fieldId )
WALBERLA_CHECK_EQUAL ( field(1,1,+2), 4 );
}
+void testScalarFieldPullReduction( IBlock * block, BlockDataID fieldId )
+{
+ GhostLayerField<int,1> & field = *(block->getData<GhostLayerField<int,1> > (fieldId));
+ field.setWithGhostLayer( 0 );
+ WALBERLA_CHECK_EQUAL(field.xSize(), 2);
+ WALBERLA_CHECK_EQUAL(field.ySize(), 2);
+ WALBERLA_CHECK_EQUAL(field.zSize(), 2);
+ // initialize the bottom ghost layer cells
+ field(0,0,-1) = 1;
+ field(0,1,-1) = 2;
+ field(1,0,-1) = 3;
+ field(1,1,-1) = 4;
+
+ // initialize the top interior cells
+ field(0,0,1) = 1;
+ field(0,1,1) = 1;
+ field(1,0,1) = 1;
+ field(1,1,1) = 1;
+
+ // communicate periodic from bottom to top with uniform pull scheme
+ field::communication::UniformPullReductionPackInfo<std::plus, GhostLayerField<int,1> > pi1 (fieldId);
+ pi1.communicateLocal( block, block, stencil::B );
+
+ // check values in top ghost layer
+ WALBERLA_CHECK_EQUAL ( field(0,0,2), 0 );
+ WALBERLA_CHECK_EQUAL ( field(0,1,2), 0 );
+ WALBERLA_CHECK_EQUAL ( field(1,0,2), 0 );
+ WALBERLA_CHECK_EQUAL ( field(1,1,2), 0 );
+
+ // check values in top interior cells
+ WALBERLA_CHECK_EQUAL ( field(0,0,1), 2 );
+ WALBERLA_CHECK_EQUAL ( field(0,1,1), 3 );
+ WALBERLA_CHECK_EQUAL ( field(1,0,1), 4 );
+ WALBERLA_CHECK_EQUAL ( field(1,1,1), 5 );
+
+ // communicate periodic from top to bottom with standard form to sync ghost layers
+ field::communication::PackInfo< GhostLayerField<int,1> > pi2 (fieldId);
+ pi2.communicateLocal( block, block, stencil::T );
+
+ // check values in bottom ghost layer
+ WALBERLA_CHECK_EQUAL ( field(0,0,-1), 2 );
+ WALBERLA_CHECK_EQUAL ( field(0,1,-1), 3 );
+ WALBERLA_CHECK_EQUAL ( field(1,0,-1), 4 );
+ WALBERLA_CHECK_EQUAL ( field(1,1,-1), 5 );
+
+ // check values in top interior cells
+ WALBERLA_CHECK_EQUAL ( field(0,0,1), 2 );
+ WALBERLA_CHECK_EQUAL ( field(0,1,1), 3 );
+ WALBERLA_CHECK_EQUAL ( field(1,0,1), 4 );
+ WALBERLA_CHECK_EQUAL ( field(1,1,1), 5 );
+}
int main(int argc, char **argv)
{
@@ -127,7 +180,8 @@ int main(int argc, char **argv)
for( auto blockIt = blocks->begin(); blockIt != blocks->end(); ++blockIt ) // block loop
testScalarField( &(*blockIt), scalarFieldId );
-
+ for( auto blockIt = blocks->begin(); blockIt != blocks->end(); ++blockIt ) // block loop
+ testScalarFieldPullReduction( &(*blockIt), scalarFieldId );
return 0;
}