1 // Copyright (c) 2017-2026, Lawrence Livermore National Security, LLC and other CEED contributors. 2 // All Rights Reserved. See the top-level LICENSE and NOTICE files for details. 3 // 4 // SPDX-License-Identifier: BSD-2-Clause 5 // 6 // This file is part of CEED: http://github.com/ceed 7 8 // libCEED + PETSc Example: CEED BPs 9 // 10 // This example demonstrates a simple usage of libCEED with PETSc to solve the CEED BP benchmark problems, see http://ceed.exascaleproject.org/bps, on 11 // a closed surface, such as the one of a discrete sphere. 12 // 13 // The code uses higher level communication protocols in DMPlex. 14 // 15 // Build with: 16 // 17 // make bpssphere [PETSC_DIR=</path/to/petsc>] [CEED_DIR=</path/to/libceed>] 18 // 19 // Sample runs: 20 // 21 // bpssphere -problem bp1 -degree 3 22 // bpssphere -problem bp2 -degree 3 23 // bpssphere -problem bp3 -degree 3 24 // bpssphere -problem bp4 -degree 3 25 // bpssphere -problem bp5 -degree 3 -ceed /cpu/self 26 // bpssphere -problem bp6 -degree 3 -ceed /gpu/cuda 27 // 28 //TESTARGS -ceed {ceed_resource} -test -problem bp3 -degree 3 -dm_refine 2 29 30 /// @file 31 /// CEED BPs example using PETSc with DMPlex 32 /// See bps.c for a "raw" implementation using a structured grid and bpsdmplex.c for an implementation using an unstructured grid. 33 static const char help[] = "Solve CEED BPs on a sphere using DMPlex in PETSc\n"; 34 35 #include "bpssphere.h" 36 37 #include <ceed.h> 38 #include <petscdmplex.h> 39 #include <petscksp.h> 40 #include <stdbool.h> 41 #include <string.h> 42 43 #include "include/libceedsetup.h" 44 #include "include/matops.h" 45 #include "include/petscutils.h" 46 #include "include/petscversion.h" 47 #include "include/sphereproblemdata.h" 48 49 int main(int argc, char **argv) { 50 MPI_Comm comm; 51 char ceed_resource[PETSC_MAX_PATH_LEN] = "/cpu/self", filename[PETSC_MAX_PATH_LEN]; 52 double my_rt_start, my_rt, rt_min, rt_max; 53 PetscInt degree = 3, q_extra, l_size, g_size, topo_dim = 2, num_comp_x = 3, num_comp_u = 1, xl_size; 54 PetscBool test_mode, benchmark_mode, read_mesh, write_solution, simplex; 55 PetscLogStage solve_stage; 56 Vec X, X_loc, rhs, rhs_loc; 57 Mat mat_O; 58 KSP ksp; 59 DM dm; 60 OperatorApplyContext op_apply_ctx, op_error_ctx; 61 Ceed ceed; 62 CeedData ceed_data; 63 CeedQFunction qf_error; 64 CeedOperator op_error; 65 CeedVector rhs_ceed, target; 66 BPType bp_choice; 67 VecType vec_type = VECSTANDARD; 68 PetscMemType mem_type; 69 70 PetscCall(PetscInitialize(&argc, &argv, NULL, help)); 71 comm = PETSC_COMM_WORLD; 72 73 // Read command line options 74 PetscOptionsBegin(comm, NULL, "CEED BPs in PETSc", NULL); 75 bp_choice = CEED_BP1; 76 PetscCall(PetscOptionsEnum("-problem", "CEED benchmark problem to solve", NULL, bp_types, (PetscEnum)bp_choice, (PetscEnum *)&bp_choice, NULL)); 77 num_comp_u = bp_options[bp_choice].num_comp_u; 78 test_mode = PETSC_FALSE; 79 PetscCall(PetscOptionsBool("-test", "Testing mode (do not print unless error is large)", NULL, test_mode, &test_mode, NULL)); 80 benchmark_mode = PETSC_FALSE; 81 PetscCall(PetscOptionsBool("-benchmark", "Benchmarking mode (prints benchmark statistics)", NULL, benchmark_mode, &benchmark_mode, NULL)); 82 write_solution = PETSC_FALSE; 83 PetscCall(PetscOptionsBool("-write_solution", "Write solution for visualization", NULL, write_solution, &write_solution, NULL)); 84 degree = test_mode ? 3 : 2; 85 PetscCall(PetscOptionsInt("-degree", "Polynomial degree of tensor product basis", NULL, degree, °ree, NULL)); 86 q_extra = bp_options[bp_choice].q_extra; 87 PetscCall(PetscOptionsInt("-q_extra", "Number of extra quadrature points", NULL, q_extra, &q_extra, NULL)); 88 PetscCall(PetscOptionsString("-ceed", "CEED resource specifier", NULL, ceed_resource, ceed_resource, sizeof(ceed_resource), NULL)); 89 read_mesh = PETSC_FALSE; 90 PetscCall(PetscOptionsString("-mesh", "Read mesh from file", NULL, filename, filename, sizeof(filename), &read_mesh)); 91 simplex = PETSC_FALSE; 92 PetscCall(PetscOptionsBool("-simplex", "Use simplices, or tensor product cells", NULL, simplex, &simplex, NULL)); 93 PetscOptionsEnd(); 94 95 // Set up libCEED 96 CeedInit(ceed_resource, &ceed); 97 CeedMemType mem_type_backend; 98 CeedGetPreferredMemType(ceed, &mem_type_backend); 99 100 // Set mesh vec_type 101 switch (mem_type_backend) { 102 case CEED_MEM_HOST: 103 vec_type = VECSTANDARD; 104 break; 105 case CEED_MEM_DEVICE: { 106 const char *resolved; 107 108 CeedGetResource(ceed, &resolved); 109 if (strstr(resolved, "/gpu/cuda")) vec_type = VECCUDA; 110 else if (strstr(resolved, "/gpu/hip")) vec_type = VECHIP; 111 else vec_type = VECSTANDARD; 112 } 113 } 114 115 // Setup DM 116 if (read_mesh) { 117 PetscCall(DMPlexCreateFromFile(PETSC_COMM_WORLD, filename, NULL, PETSC_TRUE, &dm)); 118 } else { 119 // Create the mesh as a 0-refined sphere. 120 // This will create a cubic surface, not a box, and will snap to the unit sphere upon refinement. 121 PetscCall(DMPlexCreateSphereMesh(PETSC_COMM_WORLD, topo_dim, simplex, 1., &dm)); 122 // Set the object name 123 PetscCall(PetscObjectSetName((PetscObject)dm, "Sphere")); 124 // Refine DMPlex with uniform refinement using runtime option -dm_refine 125 PetscCall(DMPlexSetRefinementUniform(dm, PETSC_TRUE)); 126 } 127 PetscCall(DMSetVecType(dm, vec_type)); 128 PetscCall(DMSetFromOptions(dm)); 129 // View DMPlex via runtime option 130 PetscCall(DMViewFromOptions(dm, NULL, "-dm_view")); 131 132 // Create DM 133 PetscCall(SetupDMByDegree(dm, degree, q_extra, num_comp_u, topo_dim, false)); 134 135 // Create vectors 136 PetscCall(DMCreateGlobalVector(dm, &X)); 137 PetscCall(VecGetLocalSize(X, &l_size)); 138 PetscCall(VecGetSize(X, &g_size)); 139 PetscCall(DMCreateLocalVector(dm, &X_loc)); 140 PetscCall(VecGetSize(X_loc, &xl_size)); 141 PetscCall(VecDuplicate(X, &rhs)); 142 143 // Operator 144 PetscCall(PetscMalloc1(1, &op_apply_ctx)); 145 PetscCall(PetscMalloc1(1, &op_error_ctx)); 146 PetscCall(MatCreateShell(comm, l_size, l_size, g_size, g_size, op_apply_ctx, &mat_O)); 147 PetscCall(MatShellSetOperation(mat_O, MATOP_MULT, (void (*)(void))MatMult_Ceed)); 148 149 // Print summary 150 if (!test_mode) { 151 PetscInt P = degree + 1, Q = P + q_extra; 152 const char *used_resource; 153 CeedGetResource(ceed, &used_resource); 154 PetscCall(PetscPrintf(comm, 155 "\n-- CEED Benchmark Problem %" CeedInt_FMT " on the Sphere -- libCEED + PETSc --\n" 156 " libCEED:\n" 157 " libCEED Backend : %s\n" 158 " libCEED Backend MemType : %s\n" 159 " Mesh:\n" 160 " Solution Order (P) : %" PetscInt_FMT "\n" 161 " Quadrature Order (Q) : %" PetscInt_FMT "\n" 162 " Additional quadrature points (q_extra) : %" PetscInt_FMT "\n" 163 " Global nodes : %" PetscInt_FMT "\n", 164 bp_choice + 1, ceed_resource, CeedMemTypes[mem_type_backend], P, Q, q_extra, g_size / num_comp_u)); 165 } 166 167 // Create RHS vector 168 PetscCall(VecDuplicate(X_loc, &rhs_loc)); 169 PetscCall(VecZeroEntries(rhs_loc)); 170 CeedVectorCreate(ceed, xl_size, &rhs_ceed); 171 PetscCall(VecP2C(rhs_loc, &mem_type, rhs_ceed)); 172 173 // Setup libCEED's objects 174 PetscCall(PetscMalloc1(1, &ceed_data)); 175 PetscCall(SetupLibceedByDegree(dm, ceed, degree, topo_dim, q_extra, num_comp_x, num_comp_u, g_size, xl_size, bp_options[bp_choice], ceed_data, true, 176 true, rhs_ceed, &target)); 177 178 // Gather RHS 179 PetscCall(VecC2P(rhs_ceed, mem_type, rhs_loc)); 180 PetscCall(VecZeroEntries(rhs)); 181 PetscCall(DMLocalToGlobal(dm, rhs_loc, ADD_VALUES, rhs)); 182 CeedVectorDestroy(&rhs_ceed); 183 184 // Create the error Q-function 185 CeedQFunctionCreateInterior(ceed, 1, bp_options[bp_choice].error, bp_options[bp_choice].error_loc, &qf_error); 186 CeedQFunctionAddInput(qf_error, "u", num_comp_u, CEED_EVAL_INTERP); 187 CeedQFunctionAddInput(qf_error, "true_soln", num_comp_u, CEED_EVAL_NONE); 188 CeedQFunctionAddInput(qf_error, "qdata", ceed_data->q_data_size, CEED_EVAL_NONE); 189 CeedQFunctionAddOutput(qf_error, "error", num_comp_u, CEED_EVAL_INTERP); 190 191 // Create the error operator 192 CeedOperatorCreate(ceed, qf_error, NULL, NULL, &op_error); 193 CeedOperatorSetField(op_error, "u", ceed_data->elem_restr_u, ceed_data->basis_u, CEED_VECTOR_ACTIVE); 194 CeedOperatorSetField(op_error, "true_soln", ceed_data->elem_restr_u_i, CEED_BASIS_NONE, target); 195 CeedOperatorSetField(op_error, "qdata", ceed_data->elem_restr_qd_i, CEED_BASIS_NONE, ceed_data->q_data); 196 CeedOperatorSetField(op_error, "error", ceed_data->elem_restr_u, ceed_data->basis_u, CEED_VECTOR_ACTIVE); 197 198 // Set up apply operator context 199 PetscCall(SetupApplyOperatorCtx(comm, dm, ceed, ceed_data, X_loc, op_apply_ctx)); 200 201 // Setup solver 202 PetscCall(KSPCreate(comm, &ksp)); 203 { 204 PC pc; 205 PetscCall(KSPGetPC(ksp, &pc)); 206 if (bp_choice == CEED_BP1 || bp_choice == CEED_BP2) { 207 PetscCall(PCSetType(pc, PCJACOBI)); 208 PetscCall(PCJacobiSetType(pc, PC_JACOBI_ROWSUM)); 209 } else { 210 PetscCall(PCSetType(pc, PCNONE)); 211 MatNullSpace nullspace; 212 213 PetscCall(MatNullSpaceCreate(PETSC_COMM_WORLD, PETSC_TRUE, 0, 0, &nullspace)); 214 PetscCall(MatSetNullSpace(mat_O, nullspace)); 215 PetscCall(MatNullSpaceDestroy(&nullspace)); 216 } 217 PetscCall(KSPSetType(ksp, KSPCG)); 218 PetscCall(KSPSetNormType(ksp, KSP_NORM_NATURAL)); 219 PetscCall(KSPSetTolerances(ksp, 1e-10, PETSC_DEFAULT, PETSC_DEFAULT, PETSC_DEFAULT)); 220 } 221 PetscCall(KSPSetFromOptions(ksp)); 222 PetscCall(KSPSetOperators(ksp, mat_O, mat_O)); 223 224 // First run, if benchmarking 225 if (benchmark_mode) { 226 PetscCall(KSPSetTolerances(ksp, 1e-10, PETSC_DEFAULT, PETSC_DEFAULT, 1)); 227 my_rt_start = MPI_Wtime(); 228 PetscCall(KSPSolve(ksp, rhs, X)); 229 my_rt = MPI_Wtime() - my_rt_start; 230 PetscCall(MPI_Allreduce(MPI_IN_PLACE, &my_rt, 1, MPI_DOUBLE, MPI_MIN, comm)); 231 // Set maxits based on first iteration timing 232 if (my_rt > 0.02) { 233 PetscCall(KSPSetTolerances(ksp, 1e-10, PETSC_DEFAULT, PETSC_DEFAULT, 5)); 234 } else { 235 PetscCall(KSPSetTolerances(ksp, 1e-10, PETSC_DEFAULT, PETSC_DEFAULT, 20)); 236 } 237 } 238 239 // Timed solve 240 PetscCall(VecZeroEntries(X)); 241 PetscCall(PetscBarrier((PetscObject)ksp)); 242 243 // -- Performance logging 244 PetscCall(PetscLogStageRegister("Solve Stage", &solve_stage)); 245 PetscCall(PetscLogStagePush(solve_stage)); 246 247 // -- Solve 248 my_rt_start = MPI_Wtime(); 249 PetscCall(KSPSolve(ksp, rhs, X)); 250 my_rt = MPI_Wtime() - my_rt_start; 251 252 // -- Performance logging 253 PetscCall(PetscLogStagePop()); 254 255 // Output results 256 { 257 KSPType ksp_type; 258 KSPConvergedReason reason; 259 PetscReal rnorm; 260 PetscInt its; 261 PetscCall(KSPGetType(ksp, &ksp_type)); 262 PetscCall(KSPGetConvergedReason(ksp, &reason)); 263 PetscCall(KSPGetIterationNumber(ksp, &its)); 264 PetscCall(KSPGetResidualNorm(ksp, &rnorm)); 265 if (!test_mode || reason < 0 || rnorm > 1e-8) { 266 PetscCall(PetscPrintf(comm, 267 " KSP:\n" 268 " KSP Type : %s\n" 269 " KSP Convergence : %s\n" 270 " Total KSP Iterations : %" PetscInt_FMT "\n" 271 " Final rnorm : %e\n", 272 ksp_type, KSPConvergedReasons[reason], its, (double)rnorm)); 273 } 274 if (!test_mode) { 275 PetscCall(PetscPrintf(comm, " Performance:\n")); 276 } 277 { 278 // Set up error operator context 279 PetscCall(SetupErrorOperatorCtx(comm, dm, ceed, ceed_data, X_loc, op_error, op_error_ctx)); 280 PetscScalar l2_error; 281 PetscCall(ComputeL2Error(X, &l2_error, op_error_ctx)); 282 PetscReal tol = 5e-4; 283 if (!test_mode || l2_error > tol) { 284 PetscCall(MPI_Allreduce(&my_rt, &rt_min, 1, MPI_DOUBLE, MPI_MIN, comm)); 285 PetscCall(MPI_Allreduce(&my_rt, &rt_max, 1, MPI_DOUBLE, MPI_MAX, comm)); 286 PetscCall(PetscPrintf(comm, 287 " L2 Error : %e\n" 288 " CG Solve Time : %g (%g) sec\n", 289 (double)l2_error, rt_max, rt_min)); 290 } 291 } 292 if (benchmark_mode && (!test_mode)) { 293 PetscCall(PetscPrintf(comm, " DoFs/Sec in CG : %g (%g) million\n", 1e-6 * g_size * its / rt_max, 294 1e-6 * g_size * its / rt_min)); 295 } 296 } 297 298 // Output solution 299 if (write_solution) { 300 PetscViewer vtk_viewer_soln; 301 302 PetscCall(PetscViewerCreate(comm, &vtk_viewer_soln)); 303 PetscCall(PetscViewerSetType(vtk_viewer_soln, PETSCVIEWERVTK)); 304 PetscCall(PetscViewerFileSetName(vtk_viewer_soln, "solution.vtu")); 305 PetscCall(VecView(X, vtk_viewer_soln)); 306 PetscCall(PetscViewerDestroy(&vtk_viewer_soln)); 307 } 308 309 // Cleanup 310 PetscCall(VecDestroy(&X)); 311 PetscCall(VecDestroy(&X_loc)); 312 PetscCall(VecDestroy(&op_apply_ctx->Y_loc)); 313 PetscCall(VecDestroy(&op_error_ctx->Y_loc)); 314 PetscCall(MatDestroy(&mat_O)); 315 PetscCall(PetscFree(op_apply_ctx)); 316 PetscCall(PetscFree(op_error_ctx)); 317 PetscCall(CeedDataDestroy(0, ceed_data)); 318 PetscCall(DMDestroy(&dm)); 319 320 PetscCall(VecDestroy(&rhs)); 321 PetscCall(VecDestroy(&rhs_loc)); 322 PetscCall(KSPDestroy(&ksp)); 323 CeedVectorDestroy(&target); 324 CeedQFunctionDestroy(&qf_error); 325 CeedOperatorDestroy(&op_error); 326 CeedDestroy(&ceed); 327 return PetscFinalize(); 328 } 329