Backport of #1015

precice · May 18, 2021 · e385063 · e385063
1 parent 0149c8d
commit e385063
Show file tree

Hide file tree

Showing 4 changed files with 9 additions and 12 deletions.
diff --git a/docs/changelog/1015.md b/docs/changelog/1015.md
@@ -0,0 +1,2 @@
+- Fixed gather-scatter communication deadlock with empty master ranks
+- Fixed empty received partitions for filtering on slaves
diff --git a/src/cplscheme/BaseCouplingScheme.cpp b/src/cplscheme/BaseCouplingScheme.cpp
@@ -75,9 +75,7 @@ void BaseCouplingScheme::sendData(m2n::PtrM2N m2n, DataMap sendData)
 
   for (const DataMap::value_type &pair : sendData) {
     int size = pair.second->values().size();
-    if (size > 0) {
-      m2n->send(pair.second->values().data(), size, pair.second->mesh->getID(), pair.second->getDimensions());
-    }
+    m2n->send(pair.second->values().data(), size, pair.second->mesh->getID(), pair.second->getDimensions());
     sentDataIDs.push_back(pair.first);
   }
   PRECICE_DEBUG("Number of sent data sets = " << sentDataIDs.size());
@@ -91,9 +89,7 @@ void BaseCouplingScheme::receiveData(m2n::PtrM2N m2n, DataMap receiveData)
   PRECICE_ASSERT(m2n->isConnected());
   for (DataMap::value_type &pair : receiveData) {
     int size = pair.second->values().size();
-    if (size > 0) {
-      m2n->receive(pair.second->values().data(), size, pair.second->mesh->getID(), pair.second->getDimensions());
-    }
+    m2n->receive(pair.second->values().data(), size, pair.second->mesh->getID(), pair.second->getDimensions());
     receivedDataIDs.push_back(pair.first);
   }
   PRECICE_DEBUG("Number of received data sets = " << receivedDataIDs.size());

diff --git a/src/m2n/PointToPointCommunication.cpp b/src/m2n/PointToPointCommunication.cpp
@@ -581,7 +581,7 @@ void PointToPointCommunication::send(double const *itemsToSend,
                                      int           valueDimension)
 {
 
-  if (_mappings.empty()) {
+  if (_mappings.empty() || size == 0) {
     return;
   }
 
@@ -605,7 +605,7 @@ void PointToPointCommunication::receive(double *itemsToReceive,
                                         size_t  size,
                                         int     valueDimension)
 {
-  if (_mappings.empty()) {
+  if (_mappings.empty() || size == 0) {
     return;
   }
 

diff --git a/src/partition/ReceivedPartition.cpp b/src/partition/ReceivedPartition.cpp
@@ -328,17 +328,16 @@ void ReceivedPartition::filterByBoundingBox()
       mesh::Mesh filteredMesh("FilteredMesh", _dimensions, _mesh->isFlipNormals(), mesh::Mesh::MESH_ID_UNDEFINED);
       mesh::filterMesh(filteredMesh, *_mesh, [&](const mesh::Vertex &v) { return _bb.contains(v); });
 
-      if (isAnyProvidedMeshNonEmpty()) {
-        PRECICE_CHECK(not _mesh->vertices().empty(), errorMeshFilteredOut(_mesh->getName()));
-      }
-
       PRECICE_DEBUG("Bounding box filter, filtered from "
                     << _mesh->vertices().size() << " to " << filteredMesh.vertices().size() << " vertices, "
                     << _mesh->edges().size() << " to " << filteredMesh.edges().size() << " edges, and "
                     << _mesh->triangles().size() << " to " << filteredMesh.triangles().size() << " triangles.");
 
       _mesh->clear();
       _mesh->addMesh(filteredMesh);
+      if (isAnyProvidedMeshNonEmpty()) {
+        PRECICE_CHECK(not _mesh->vertices().empty(), errorMeshFilteredOut(_mesh->getName()));
+      }
     } else {
       PRECICE_ASSERT(_geometricFilter == NO_FILTER);
     }