Collection of minor performance fixes during profiling and GPU testing

palace/fem/fespace.hpp

@@ -300,7 +300,8 @@ class AuxiliaryFiniteElementSpaceHierarchy
   std::vector<const Operator *> GetDiscreteInterpolators() const
   {
     std::vector<const Operator *> G_(GetNumLevels());
-    for (std::size_t l = 0; l < G_.size(); l++)
+    G_[0] = nullptr;  // No discrete interpolator for coarsest level
+    for (std::size_t l = 1; l < G_.size(); l++)
     {
       G_[l] = &GetDiscreteInterpolatorAtLevel(l);
     }

palace/fem/libceed/basis.cpp

@@ -192,7 +192,7 @@ void InitInterpolatorBasis(const mfem::FiniteElement &trial_fe,
   if constexpr (false)
   {
     std::cout << "New interpolator basis (" << ceed << ", " << &trial_fe << ", " << &test_fe
-              << ")\n";
+              << ", " << (trial_fe.GetMapType() == test_fe.GetMapType()) << ")\n";
   }
   if constexpr (false)
   {

palace/fem/libceed/ceed.cpp

@@ -3,6 +3,7 @@
 
 #include "ceed.hpp"
 
+#include <string_view>
 #include "utils/omp.hpp"
 
 #if defined(MFEM_USE_OPENMP)
@@ -31,7 +32,9 @@ void Initialize(const char *resource, const char *jit_source_dir)
     PalacePragmaOmp(master)
     {
 #if defined(MFEM_USE_OPENMP)
-      const int nt = omp_get_num_threads();
+      // Only parallelize libCEED operators over threads when not using the GPU.
+      const int nt =
+          !std::string_view(resource).compare(0, 4, "/cpu") ? omp_get_num_threads() : 1;
 #else
       const int nt = 1;
 #endif

palace/fem/libceed/integrator.cpp

@@ -346,7 +346,9 @@ int CeedGeometryDataGetSpaceDimension(CeedElemRestriction geom_data_restr, CeedI
 
 void AssembleCeedGeometryData(Ceed ceed, CeedElemRestriction mesh_restr,
                               CeedBasis mesh_basis, CeedVector mesh_nodes,
-                              CeedVector geom_data, CeedElemRestriction geom_data_restr)
+                              CeedElemRestriction attr_restr, CeedBasis attr_basis,
+                              CeedVector elem_attr, CeedVector geom_data,
+                              CeedElemRestriction geom_data_restr)
 {
   CeedInt dim, space_dim, num_elem, num_qpts;
   PalaceCeedCall(ceed, CeedBasisGetDimension(mesh_basis, &dim));
@@ -389,6 +391,7 @@ void AssembleCeedGeometryData(Ceed ceed, CeedElemRestriction mesh_restr,
   }
 
   // Inputs
+  PalaceCeedCall(ceed, CeedQFunctionAddInput(build_qf, "attr", 1, CEED_EVAL_INTERP));
   PalaceCeedCall(ceed, CeedQFunctionAddInput(build_qf, "q_w", 1, CEED_EVAL_WEIGHT));
   PalaceCeedCall(
       ceed, CeedQFunctionAddInput(build_qf, "grad_x", space_dim * dim, CEED_EVAL_GRAD));
@@ -409,6 +412,8 @@ void AssembleCeedGeometryData(Ceed ceed, CeedElemRestriction mesh_restr,
   PalaceCeedCall(ceed, CeedOperatorCreate(ceed, build_qf, nullptr, nullptr, &build_op));
   PalaceCeedCall(ceed, CeedQFunctionDestroy(&build_qf));
 
+  PalaceCeedCall(ceed,
+                 CeedOperatorSetField(build_op, "attr", attr_restr, attr_basis, elem_attr));
   PalaceCeedCall(ceed, CeedOperatorSetField(build_op, "q_w", CEED_ELEMRESTRICTION_NONE,
                                             mesh_basis, CEED_VECTOR_NONE));
   PalaceCeedCall(ceed, CeedOperatorSetField(build_op, "grad_x", mesh_restr, mesh_basis,

palace/fem/libceed/integrator.hpp

@@ -53,7 +53,9 @@ int CeedGeometryDataGetSpaceDimension(CeedElemRestriction geom_data_restr, CeedI
 // libCEED operator.
 void AssembleCeedGeometryData(Ceed ceed, CeedElemRestriction mesh_restr,
                               CeedBasis mesh_basis, CeedVector mesh_nodes,
-                              CeedVector geom_data, CeedElemRestriction geom_data_restr);
+                              CeedElemRestriction attr_restr, CeedBasis attr_basis,
+                              CeedVector elem_attr, CeedVector geom_data,
+                              CeedElemRestriction geom_data_restr);
 
 // Construct libCEED operator using the given quadrature data, element restriction, and
 // basis objects.

palace/fem/mesh.cpp

@@ -137,10 +137,8 @@ auto GetElementIndices(const mfem::ParMesh &mesh, bool use_bdr, int start, int s
   return element_indices;
 }
 
-template <typename T>
-auto AssembleGeometryData(const mfem::GridFunction &mesh_nodes, Ceed ceed,
-                          mfem::Geometry::Type geom, std::vector<int> &indices,
-                          T GetCeedAttribute)
+auto AssembleGeometryData(Ceed ceed, mfem::Geometry::Type geom, std::vector<int> &indices,
+                          const mfem::GridFunction &mesh_nodes, const Vector &elem_attr)
 {
   const mfem::FiniteElementSpace &mesh_fespace = *mesh_nodes.FESpace();
   const mfem::Mesh &mesh = *mesh_fespace.GetMesh();
@@ -151,68 +149,50 @@ auto AssembleGeometryData(const mfem::GridFunction &mesh_nodes, Ceed ceed,
   data.indices = std::move(indices);
   const std::size_t num_elem = data.indices.size();
 
-  // Allocate storage for geometry factor data (stored as attribute + quadrature weight +
-  // Jacobian, column-major).
+  // Construct mesh node element restriction and basis.
   CeedElemRestriction mesh_restr =
       FiniteElementSpace::BuildCeedElemRestriction(mesh_fespace, ceed, geom, data.indices);
   CeedBasis mesh_basis = FiniteElementSpace::BuildCeedBasis(mesh_fespace, ceed, geom);
-  CeedInt num_qpts, geom_data_size = 2 + data.space_dim * data.dim;
+  CeedVector mesh_nodes_vec;
+  ceed::InitCeedVector(mesh_nodes, ceed, &mesh_nodes_vec);
+  CeedInt num_qpts;
   PalaceCeedCall(ceed, CeedBasisGetNumQuadraturePoints(mesh_basis, &num_qpts));
-  PalaceCeedCall(
-      ceed, CeedVectorCreate(ceed, num_elem * num_qpts * geom_data_size, &data.geom_data));
 
-  // Data for quadrature point i, component j, element k is found at index i * strides[0] +
-  // j * strides[1] + k * strides[2].
-  CeedMemType mem;
-  CeedInt strides[3];
-  PalaceCeedCall(ceed, CeedGetPreferredMemType(ceed, &mem));
-  if (mfem::Device::Allows(mfem::Backend::DEVICE_MASK) && mem == CEED_MEM_DEVICE)
-  {
-    // GPU backends have CEED_STRIDES_BACKEND = {1, num_elem * num_qpts, num_qpts}.
-    strides[0] = 1;
-    strides[1] = num_elem * num_qpts;
-    strides[2] = num_qpts;
-  }
-  else
+  // Construct element attribute element restriction and basis.
+  CeedElemRestriction attr_restr;
+  CeedBasis attr_basis;
+  PalaceCeedCall(ceed, CeedElemRestrictionCreateStrided(ceed, num_elem, 1, 1, num_elem,
+                                                        CEED_STRIDES_BACKEND, &attr_restr));
   {
-    // CPU backends have CEED_STRIDES_BACKEND = {1, num_qpts, num_qpts * geom_data_size}.
-    strides[0] = 1;
-    strides[1] = num_qpts;
-    strides[2] = num_qpts * geom_data_size;
+    Vector Bt(num_qpts);
+    Bt = 1.0;
+    PalaceCeedCall(ceed,
+                   CeedBasisCreateH1(ceed, ceed::GetCeedTopology(geom), 1, 1, num_qpts,
+                                     Bt.GetData(), nullptr, nullptr, nullptr, &attr_basis));
   }
-  PalaceCeedCall(ceed,
-                 CeedElemRestrictionCreateStrided(ceed, num_elem, num_qpts, geom_data_size,
-                                                  num_elem * num_qpts * geom_data_size,
-                                                  strides, &data.geom_data_restr));
-
-  // Compute the required geometry factors at quadrature points.
-  CeedVector mesh_nodes_vec;
-  ceed::InitCeedVector(mesh_nodes, ceed, &mesh_nodes_vec);
+  CeedVector elem_attr_vec;
+  ceed::InitCeedVector(elem_attr, ceed, &elem_attr_vec);
 
-  ceed::AssembleCeedGeometryData(ceed, mesh_restr, mesh_basis, mesh_nodes_vec,
-                                 data.geom_data, data.geom_data_restr);
+  // Allocate storage for geometry factor data (stored as attribute + quadrature weight +
+  // Jacobian, column-major).
+  CeedInt geom_data_size = 2 + data.space_dim * data.dim;
+  PalaceCeedCall(
+      ceed, CeedVectorCreate(ceed, num_elem * num_qpts * geom_data_size, &data.geom_data));
+  PalaceCeedCall(
+      ceed, CeedElemRestrictionCreateStrided(ceed, num_elem, num_qpts, geom_data_size,
+                                             num_elem * num_qpts * geom_data_size,
+                                             CEED_STRIDES_BACKEND, &data.geom_data_restr));
 
+  // Compute the required geometry factors at quadrature points.
+  ceed::AssembleCeedGeometryData(ceed, mesh_restr, mesh_basis, mesh_nodes_vec, attr_restr,
+                                 attr_basis, elem_attr_vec, data.geom_data,
+                                 data.geom_data_restr);
   PalaceCeedCall(ceed, CeedVectorDestroy(&mesh_nodes_vec));
   PalaceCeedCall(ceed, CeedElemRestrictionDestroy(&mesh_restr));
   PalaceCeedCall(ceed, CeedBasisDestroy(&mesh_basis));
-
-  // Compute element attribute quadrature data. All inputs to a QFunction require the same
-  // number of quadrature points, so we store the attribute at each quadrature point. This
-  // is the first component of the quadrature data.
-  {
-    CeedScalar *geom_data_array;
-    PalaceCeedCall(ceed,
-                   CeedVectorGetArray(data.geom_data, CEED_MEM_HOST, &geom_data_array));
-    for (std::size_t k = 0; k < num_elem; k++)
-    {
-      const auto attr = GetCeedAttribute(data.indices[k]);
-      for (CeedInt i = 0; i < num_qpts; i++)
-      {
-        geom_data_array[i * strides[0] + k * strides[2]] = attr;
-      }
-    }
-    CeedVectorRestoreArray(data.geom_data, &geom_data_array);
-  }
+  PalaceCeedCall(ceed, CeedVectorDestroy(&elem_attr_vec));
+  PalaceCeedCall(ceed, CeedElemRestrictionDestroy(&attr_restr));
+  PalaceCeedCall(ceed, CeedBasisDestroy(&attr_basis));
 
   return data;
 }
@@ -278,8 +258,13 @@ auto BuildCeedGeomFactorData(
     }();
     for (auto &[geom, indices] : element_indices)
     {
-      geom_data_map.emplace(geom, AssembleGeometryData(*mesh.GetNodes(), ceed, geom,
-                                                       indices, GetCeedAttribute));
+      Vector elem_attr(indices.size());
+      for (std::size_t k = 0; k < indices.size(); k++)
+      {
+        elem_attr[k] = GetCeedAttribute(indices[k]);
+      }
+      geom_data_map.emplace(
+          geom, AssembleGeometryData(ceed, geom, indices, *mesh.GetNodes(), elem_attr));
     }
   }
 
@@ -304,8 +289,13 @@ auto BuildCeedGeomFactorData(
     };
     for (auto &[geom, indices] : element_indices)
     {
-      geom_data_map.emplace(geom, AssembleGeometryData(*mesh.GetNodes(), ceed, geom,
-                                                       indices, GetCeedAttribute));
+      Vector elem_attr(indices.size());
+      for (std::size_t k = 0; k < indices.size(); k++)
+      {
+        elem_attr[k] = GetCeedAttribute(indices[k]);
+      }
+      geom_data_map.emplace(
+          geom, AssembleGeometryData(ceed, geom, indices, *mesh.GetNodes(), elem_attr));
     }
   }
 

palace/fem/qfunctions/21/geom_21_qf.h

@@ -9,19 +9,19 @@
 CEED_QFUNCTION(f_build_geom_factor_21)(void *, CeedInt Q, const CeedScalar *const *in,
                                        CeedScalar *const *out)
 {
-  const CeedScalar *qw = in[0], *J = in[1];
-  CeedScalar *attr = out[0], *wdetJ = out[0] + Q, *adjJt = out[0] + 2 * Q;
+  const CeedScalar *attr = in[0], *qw = in[1], *J = in[2];
+  CeedScalar *qd_attr = out[0], *qd_wdetJ = out[0] + Q, *qd_adjJt = out[0] + 2 * Q;
 
   CeedPragmaSIMD for (CeedInt i = 0; i < Q; i++)
   {
     CeedScalar J_loc[2], adjJt_loc[2];
     MatUnpack21(J + i, Q, J_loc);
     const CeedScalar detJ = AdjJt21<true>(J_loc, adjJt_loc);
 
-    attr[i] = 0;
-    wdetJ[i] = qw[i] * detJ;
-    adjJt[i + Q * 0] = adjJt_loc[0] / detJ;
-    adjJt[i + Q * 1] = adjJt_loc[1] / detJ;
+    qd_attr[i] = attr[i];
+    qd_wdetJ[i] = qw[i] * detJ;
+    qd_adjJt[i + Q * 0] = adjJt_loc[0] / detJ;
+    qd_adjJt[i + Q * 1] = adjJt_loc[1] / detJ;
   }
   return 0;
 }

palace/fem/qfunctions/22/geom_22_qf.h

@@ -9,21 +9,21 @@
 CEED_QFUNCTION(f_build_geom_factor_22)(void *, CeedInt Q, const CeedScalar *const *in,
                                        CeedScalar *const *out)
 {
-  const CeedScalar *qw = in[0], *J = in[1];
-  CeedScalar *attr = out[0], *wdetJ = out[0] + Q, *adjJt = out[0] + 2 * Q;
+  const CeedScalar *attr = in[0], *qw = in[1], *J = in[2];
+  CeedScalar *qd_attr = out[0], *qd_wdetJ = out[0] + Q, *qd_adjJt = out[0] + 2 * Q;
 
   CeedPragmaSIMD for (CeedInt i = 0; i < Q; i++)
   {
     CeedScalar J_loc[4], adjJt_loc[4];
     MatUnpack22(J + i, Q, J_loc);
     const CeedScalar detJ = AdjJt22<true>(J_loc, adjJt_loc);
 
-    attr[i] = 0;
-    wdetJ[i] = qw[i] * detJ;
-    adjJt[i + Q * 0] = adjJt_loc[0] / detJ;
-    adjJt[i + Q * 1] = adjJt_loc[1] / detJ;
-    adjJt[i + Q * 2] = adjJt_loc[2] / detJ;
-    adjJt[i + Q * 3] = adjJt_loc[3] / detJ;
+    qd_attr[i] = attr[i];
+    qd_wdetJ[i] = qw[i] * detJ;
+    qd_adjJt[i + Q * 0] = adjJt_loc[0] / detJ;
+    qd_adjJt[i + Q * 1] = adjJt_loc[1] / detJ;
+    qd_adjJt[i + Q * 2] = adjJt_loc[2] / detJ;
+    qd_adjJt[i + Q * 3] = adjJt_loc[3] / detJ;
   }
   return 0;
 }

palace/fem/qfunctions/32/geom_32_qf.h

@@ -9,23 +9,23 @@
 CEED_QFUNCTION(f_build_geom_factor_32)(void *, CeedInt Q, const CeedScalar *const *in,
                                        CeedScalar *const *out)
 {
-  const CeedScalar *qw = in[0], *J = in[1];
-  CeedScalar *attr = out[0], *wdetJ = out[0] + Q, *adjJt = out[0] + 2 * Q;
+  const CeedScalar *attr = in[0], *qw = in[1], *J = in[2];
+  CeedScalar *qd_attr = out[0], *qd_wdetJ = out[0] + Q, *qd_adjJt = out[0] + 2 * Q;
 
   CeedPragmaSIMD for (CeedInt i = 0; i < Q; i++)
   {
     CeedScalar J_loc[6], adjJt_loc[6];
     MatUnpack32(J + i, Q, J_loc);
     const CeedScalar detJ = AdjJt32<true>(J_loc, adjJt_loc);
 
-    attr[i] = 0;
-    wdetJ[i] = qw[i] * detJ;
-    adjJt[i + Q * 0] = adjJt_loc[0] / detJ;
-    adjJt[i + Q * 1] = adjJt_loc[1] / detJ;
-    adjJt[i + Q * 2] = adjJt_loc[2] / detJ;
-    adjJt[i + Q * 3] = adjJt_loc[3] / detJ;
-    adjJt[i + Q * 4] = adjJt_loc[4] / detJ;
-    adjJt[i + Q * 5] = adjJt_loc[5] / detJ;
+    qd_attr[i] = attr[i];
+    qd_wdetJ[i] = qw[i] * detJ;
+    qd_adjJt[i + Q * 0] = adjJt_loc[0] / detJ;
+    qd_adjJt[i + Q * 1] = adjJt_loc[1] / detJ;
+    qd_adjJt[i + Q * 2] = adjJt_loc[2] / detJ;
+    qd_adjJt[i + Q * 3] = adjJt_loc[3] / detJ;
+    qd_adjJt[i + Q * 4] = adjJt_loc[4] / detJ;
+    qd_adjJt[i + Q * 5] = adjJt_loc[5] / detJ;
   }
   return 0;
 }

palace/fem/qfunctions/33/geom_33_qf.h

@@ -9,26 +9,26 @@
 CEED_QFUNCTION(f_build_geom_factor_33)(void *, CeedInt Q, const CeedScalar *const *in,
                                        CeedScalar *const *out)
 {
-  const CeedScalar *qw = in[0], *J = in[1];
-  CeedScalar *attr = out[0], *wdetJ = out[0] + Q, *adjJt = out[0] + 2 * Q;
+  const CeedScalar *attr = in[0], *qw = in[1], *J = in[2];
+  CeedScalar *qd_attr = out[0], *qd_wdetJ = out[0] + Q, *qd_adjJt = out[0] + 2 * Q;
 
   CeedPragmaSIMD for (CeedInt i = 0; i < Q; i++)
   {
     CeedScalar J_loc[9], adjJt_loc[9];
     MatUnpack33(J + i, Q, J_loc);
     const CeedScalar detJ = AdjJt33<true>(J_loc, adjJt_loc);
 
-    attr[i] = 0;
-    wdetJ[i] = qw[i] * detJ;
-    adjJt[i + Q * 0] = adjJt_loc[0] / detJ;
-    adjJt[i + Q * 1] = adjJt_loc[1] / detJ;
-    adjJt[i + Q * 2] = adjJt_loc[2] / detJ;
-    adjJt[i + Q * 3] = adjJt_loc[3] / detJ;
-    adjJt[i + Q * 4] = adjJt_loc[4] / detJ;
-    adjJt[i + Q * 5] = adjJt_loc[5] / detJ;
-    adjJt[i + Q * 6] = adjJt_loc[6] / detJ;
-    adjJt[i + Q * 7] = adjJt_loc[7] / detJ;
-    adjJt[i + Q * 8] = adjJt_loc[8] / detJ;
+    qd_attr[i] = attr[i];
+    qd_wdetJ[i] = qw[i] * detJ;
+    qd_adjJt[i + Q * 0] = adjJt_loc[0] / detJ;
+    qd_adjJt[i + Q * 1] = adjJt_loc[1] / detJ;
+    qd_adjJt[i + Q * 2] = adjJt_loc[2] / detJ;
+    qd_adjJt[i + Q * 3] = adjJt_loc[3] / detJ;
+    qd_adjJt[i + Q * 4] = adjJt_loc[4] / detJ;
+    qd_adjJt[i + Q * 5] = adjJt_loc[5] / detJ;
+    qd_adjJt[i + Q * 6] = adjJt_loc[6] / detJ;
+    qd_adjJt[i + Q * 7] = adjJt_loc[7] / detJ;
+    qd_adjJt[i + Q * 8] = adjJt_loc[8] / detJ;
   }
   return 0;
 }

palace/fem/qfunctions/geom_qf.h

@@ -6,8 +6,9 @@
 
 // libCEED QFunction for building geometry factors for integration and transformations.
 // At every quadrature point, compute qw * det(J) and adj(J)^T / |J| and store the result.
-// in[0] is quadrature weights, shape [Q]
-// in[1] is Jacobians, shape [qcomp=dim, ncomp=space_dim, Q]
+// in[0] is element attributes, shape [Q]
+// in[1] is quadrature weights, shape [Q]
+// in[2] is Jacobians, shape [qcomp=dim, ncomp=space_dim, Q]
 // out[0] is quadrature data, stored as {attribute, Jacobian determinant, (transpose)
 //        adjugate Jacobian} quadrature data, shape [ncomp=2+space_dim*dim, Q]