Actual source code: gdsw.c

  1: #include <petsc/private/pcmgimpl.h>
  2: #include <petsc/private/pcbddcimpl.h>
  3: #include <petsc/private/pcbddcprivateimpl.h>

  5: static PetscErrorCode PCMGGDSWSetUp(PC pc, PetscInt l, DM dm, KSP smooth, PetscInt Nc, Mat A, PetscInt *ns, Mat **sA_IG_n, KSP **sksp_n, IS **sI_n, IS **sG_n, Mat **sGf_n, IS **sGi_n, IS **sGiM_n)
  6: {
  7:   KSP                   *sksp;
  8:   PC                     pcbddc = NULL, smoothpc;
  9:   PC_BDDC               *ipcbddc;
 10:   PC_IS                 *ipcis;
 11:   Mat                   *sA_IG, *sGf, cmat, lA;
 12:   ISLocalToGlobalMapping l2g;
 13:   IS                    *sI, *sG, *sGi, *sGiM, cref;
 14:   PCBDDCSubSchurs        sub_schurs = NULL;
 15:   PCBDDCGraph            graph;
 16:   const char            *prefix;
 17:   const PetscScalar     *tdata;
 18:   PetscScalar           *data, *cdata;
 19:   PetscReal              tol = 0.0, otol;
 20:   const PetscInt        *ia, *ja;
 21:   PetscInt              *ccii, *cridx;
 22:   PetscInt               i, j, ngct, ng, dbg = 0, odbg, minmax[2] = {0, PETSC_MAX_INT}, ominmax[2], vsize;
 23:   PetscBool              flg, userdefined = PETSC_TRUE, reuse_solver = PETSC_TRUE, reduced = PETSC_FALSE;

 25:   PetscFunctionBegin;
 26:   PetscCall(MatGetBlockSize(A, &vsize));
 27:   PetscCall(KSPGetOptionsPrefix(smooth, &prefix));
 28:   PetscOptionsBegin(PetscObjectComm((PetscObject)smooth), prefix, "GDSW options", "PC");
 29:   PetscCall(PetscOptionsReal("-gdsw_tolerance", "Tolerance for eigenvalue problem", NULL, tol, &tol, NULL));
 30:   PetscCall(PetscOptionsBool("-gdsw_userdefined", "Use user-defined functions in addition to those adaptively generated", NULL, userdefined, &userdefined, NULL));
 31:   PetscCall(PetscOptionsIntArray("-gdsw_minmax", "Minimum and maximum number of basis functions per connected component for adaptive GDSW", NULL, minmax, (i = 2, &i), NULL));
 32:   PetscCall(PetscOptionsInt("-gdsw_vertex_size", "Connected components smaller or equal to vertex size will be considered as vertices", NULL, vsize, &vsize, NULL));
 33:   PetscCall(PetscOptionsBool("-gdsw_reuse", "Reuse interior solver from Schur complement computations", NULL, reuse_solver, &reuse_solver, NULL));
 34:   PetscCall(PetscOptionsBool("-gdsw_reduced", "Reduced GDSW", NULL, reduced, &reduced, NULL));
 35:   PetscCall(PetscOptionsInt("-gdsw_debug", "Debug output", NULL, dbg, &dbg, NULL));
 36:   PetscOptionsEnd();

 38:   PetscCall(PetscObjectTypeCompare((PetscObject)A, MATIS, &flg));
 39:   if (!flg) {
 40:     MatNullSpace nnsp;

 42:     PetscCall(MatGetNearNullSpace(A, &nnsp));
 43:     PetscCall(PetscObjectReference((PetscObject)nnsp));
 44:     PetscCall(MatConvert(A, MATIS, MAT_INITIAL_MATRIX, &A));
 45:     PetscCall(MatSetNearNullSpace(A, nnsp));
 46:     PetscCall(MatNullSpaceDestroy(&nnsp));
 47:   } else PetscCall(PetscObjectReference((PetscObject)A));

 49:   /* TODO Multi sub */
 50:   *ns = 1;
 51:   PetscCall(PetscMalloc1(*ns, &sA_IG));
 52:   PetscCall(PetscMalloc1(*ns, &sksp));
 53:   PetscCall(PetscMalloc1(*ns, &sI));
 54:   PetscCall(PetscMalloc1(*ns, &sG));
 55:   PetscCall(PetscMalloc1(*ns, &sGf));
 56:   PetscCall(PetscMalloc1(*ns, &sGi));
 57:   PetscCall(PetscMalloc1(*ns, &sGiM));
 58:   *sA_IG_n = sA_IG;
 59:   *sksp_n  = sksp;
 60:   *sI_n    = sI;
 61:   *sG_n    = sG;
 62:   *sGf_n   = sGf;
 63:   *sGi_n   = sGi;
 64:   *sGiM_n  = sGiM;

 66:   /* submatrices and solvers */
 67:   PetscCall(KSPGetPC(smooth, &smoothpc));
 68:   PetscCall(PetscObjectTypeCompareAny((PetscObject)smoothpc, &flg, PCBDDC, ""));
 69:   if (!flg) {
 70:     Mat smoothA;

 72:     PetscCall(PCGetOperators(smoothpc, &smoothA, NULL));
 73:     PetscCall(PCCreate(PetscObjectComm((PetscObject)A), &pcbddc));
 74:     PetscCall(PCSetType(pcbddc, PCBDDC));
 75:     PetscCall(PCSetOperators(pcbddc, smoothA, A));
 76:     PetscCall(PCISSetUp(pcbddc, PETSC_TRUE, PETSC_FALSE));
 77:   } else {
 78:     PetscCall(PetscObjectReference((PetscObject)smoothpc));
 79:     pcbddc = smoothpc;
 80:   }
 81:   ipcis   = (PC_IS *)pcbddc->data;
 82:   ipcbddc = (PC_BDDC *)pcbddc->data;
 83:   PetscCall(PetscObjectReference((PetscObject)ipcis->A_IB));
 84:   PetscCall(PetscObjectReference((PetscObject)ipcis->is_I_global));
 85:   PetscCall(PetscObjectReference((PetscObject)ipcis->is_B_global));
 86:   sA_IG[0] = ipcis->A_IB;
 87:   sI[0]    = ipcis->is_I_global;
 88:   sG[0]    = ipcis->is_B_global;

 90:   PetscCall(KSPCreate(PetscObjectComm((PetscObject)ipcis->A_II), &sksp[0]));
 91:   PetscCall(KSPSetOperators(sksp[0], ipcis->A_II, ipcis->pA_II));
 92:   PetscCall(KSPSetOptionsPrefix(sksp[0], prefix));
 93:   PetscCall(KSPAppendOptionsPrefix(sksp[0], "gdsw_"));
 94:   PetscCall(KSPSetFromOptions(sksp[0]));

 96:   /* analyze interface */
 97:   PetscCall(MatISGetLocalMat(A, &lA));
 98:   graph = ipcbddc->mat_graph;
 99:   if (!flg) {
100:     PetscInt N;

102:     PetscCall(MatISGetLocalToGlobalMapping(A, &l2g, NULL));
103:     PetscCall(MatGetSize(A, &N, NULL));
104:     graph->commsizelimit = 0; /* don't use the COMM_SELF variant of the graph */
105:     PetscCall(PCBDDCGraphInit(graph, l2g, N, PETSC_MAX_INT));
106:     PetscCall(MatGetRowIJ(lA, 0, PETSC_TRUE, PETSC_FALSE, &graph->nvtxs_csr, (const PetscInt **)&graph->xadj, (const PetscInt **)&graph->adjncy, &flg));
107:     PetscCall(PCBDDCGraphSetUp(graph, vsize, NULL, NULL, 0, NULL, NULL));
108:     PetscCall(MatRestoreRowIJ(lA, 0, PETSC_TRUE, PETSC_FALSE, &graph->nvtxs_csr, (const PetscInt **)&graph->xadj, (const PetscInt **)&graph->adjncy, &flg));
109:     PetscCall(PCBDDCGraphComputeConnectedComponents(graph));
110:   }
111:   l2g = graph->l2gmap;
112:   if (reduced) {
113:     PetscContainer        gcand;
114:     PCBDDCGraphCandidates cand;
115:     PetscErrorCode (*rgdsw)(DM, PetscInt *, IS **);

117:     PetscCall(PetscObjectQueryFunction((PetscObject)dm, "DMComputeLocalRGDSWSets", &rgdsw));
118:     PetscCheck(rgdsw, PETSC_COMM_SELF, PETSC_ERR_SUP, "Not supported");
119:     PetscCall(PetscNew(&cand));
120:     PetscCall((*rgdsw)(dm, &cand->nfc, &cand->Faces));
121:     /* filter interior (if any) and guarantee IS are ordered by global numbering */
122:     for (i = 0; i < cand->nfc; i++) {
123:       IS is, is2;

125:       PetscCall(ISLocalToGlobalMappingApplyIS(l2g, cand->Faces[i], &is));
126:       PetscCall(ISDestroy(&cand->Faces[i]));
127:       PetscCall(ISSort(is));
128:       PetscCall(ISGlobalToLocalMappingApplyIS(l2g, IS_GTOLM_DROP, is, &is2));
129:       PetscCall(ISDestroy(&is));
130:       PetscCall(ISGlobalToLocalMappingApplyIS(ipcis->BtoNmap, IS_GTOLM_DROP, is2, &is));
131:       PetscCall(ISDestroy(&is2));
132:       PetscCall(ISLocalToGlobalMappingApplyIS(ipcis->BtoNmap, is, &cand->Faces[i]));
133:       PetscCall(ISDestroy(&is));
134:     }
135:     PetscCall(PetscContainerCreate(PETSC_COMM_SELF, &gcand));
136:     PetscCall(PetscContainerSetPointer(gcand, cand));
137:     PetscCall(PetscContainerSetUserDestroy(gcand, PCBDDCDestroyGraphCandidatesIS));
138:     PetscCall(PetscObjectCompose((PetscObject)l2g, "_PCBDDCGraphCandidatesIS", (PetscObject)gcand));
139:     PetscCall(PetscContainerDestroy(&gcand));
140:   }

142:   /* interface functions */
143:   otol                           = ipcbddc->adaptive_threshold[1];
144:   odbg                           = ipcbddc->dbg_flag;
145:   ominmax[0]                     = ipcbddc->adaptive_nmin;
146:   ominmax[1]                     = ipcbddc->adaptive_nmax;
147:   ipcbddc->adaptive_threshold[1] = tol;
148:   ipcbddc->dbg_flag              = dbg;
149:   ipcbddc->adaptive_nmin         = minmax[0];
150:   ipcbddc->adaptive_nmax         = minmax[1];
151:   if (tol != 0.0) { /* adaptive */
152:     Mat lS;

154:     PetscCall(MatCreateSchurComplement(ipcis->A_II, ipcis->pA_II, ipcis->A_IB, ipcis->A_BI, ipcis->A_BB, &lS));
155:     PetscCall(KSPGetOptionsPrefix(sksp[0], &prefix));
156:     PetscCall(PCBDDCSubSchursCreate(&sub_schurs));
157:     PetscCall(PCBDDCSubSchursInit(sub_schurs, prefix, ipcis->is_I_local, ipcis->is_B_local, graph, ipcis->BtoNmap, PETSC_FALSE, PETSC_TRUE));
158:     if (userdefined) PetscCall(PCBDDCComputeFakeChange(pcbddc, PETSC_FALSE, graph, NULL, &cmat, &cref, NULL, &flg));
159:     else {
160:       cmat = NULL;
161:       cref = NULL;
162:     }
163:     PetscCall(PCBDDCSubSchursSetUp(sub_schurs, lA, lS, PETSC_TRUE, NULL, NULL, -1, NULL, PETSC_TRUE, reuse_solver, PETSC_FALSE, 0, NULL, NULL, cmat, cref));
164:     PetscCall(MatDestroy(&lS));
165:     PetscCall(MatDestroy(&cmat));
166:     PetscCall(ISDestroy(&cref));
167:     if (sub_schurs->reuse_solver) {
168:       PetscCall(KSPSetPC(sksp[0], sub_schurs->reuse_solver->interior_solver));
169:       PetscCall(PCDestroy(&sub_schurs->reuse_solver->interior_solver));
170:       sub_schurs->reuse_solver = NULL;
171:     }
172:   }
173:   PetscCall(PCBDDCComputeFakeChange(pcbddc, PETSC_TRUE, graph, sub_schurs, &cmat, &cref, &sGiM[0], NULL));
174:   PetscCall(PCBDDCSubSchursDestroy(&sub_schurs));
175:   ipcbddc->adaptive_threshold[1] = otol;
176:   ipcbddc->dbg_flag              = odbg;
177:   ipcbddc->adaptive_nmin         = ominmax[0];
178:   ipcbddc->adaptive_nmax         = ominmax[1];

180:   PetscCall(ISLocalToGlobalMappingApplyIS(l2g, cref, &sGi[0]));
181:   PetscCall(ISDestroy(&cref));

183:   PetscCall(MatSeqAIJGetArrayRead(cmat, &tdata));
184:   PetscCall(MatGetRowIJ(cmat, 0, PETSC_FALSE, PETSC_FALSE, &ngct, &ia, &ja, &flg));
185:   PetscCheck(flg, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Error in MatGetRowIJ");

187:   PetscCall(PetscMalloc1(ngct + 1, &ccii));
188:   PetscCall(PetscMalloc1(ia[ngct], &cridx));
189:   PetscCall(PetscMalloc1(ia[ngct], &cdata));

191:   PetscCall(PetscArraycpy(ccii, ia, ngct + 1));
192:   PetscCall(PetscArraycpy(cdata, tdata, ia[ngct]));
193:   PetscCall(ISGlobalToLocalMappingApply(ipcis->BtoNmap, IS_GTOLM_DROP, ia[ngct], ja, &i, cridx));
194:   PetscCheck(i == ia[ngct], PETSC_COMM_SELF, PETSC_ERR_PLIB, "Error in G2L");

196:   PetscCall(MatRestoreRowIJ(cmat, 0, PETSC_FALSE, PETSC_FALSE, &i, &ia, &ja, &flg));
197:   PetscCall(MatSeqAIJRestoreArrayRead(cmat, &tdata));
198:   PetscCall(MatDestroy(&cmat));

200:   /* populate dense matrix */
201:   PetscCall(ISGetLocalSize(sG[0], &ng));
202:   PetscCall(MatCreateSeqDense(PETSC_COMM_SELF, ng, ngct, NULL, &sGf[0]));
203:   PetscCall(MatDenseGetArrayWrite(sGf[0], &data));
204:   for (i = 0; i < ngct; i++)
205:     for (j = ccii[i]; j < ccii[i + 1]; j++) data[ng * i + cridx[j]] = cdata[j];
206:   PetscCall(MatDenseRestoreArrayWrite(sGf[0], &data));

208:   PetscCall(PetscFree(cdata));
209:   PetscCall(PetscFree(ccii));
210:   PetscCall(PetscFree(cridx));
211:   PetscCall(PCDestroy(&pcbddc));
212:   PetscCall(MatDestroy(&A));
213:   PetscFunctionReturn(PETSC_SUCCESS);
214: }

216: PetscErrorCode PCMGGDSWCreateCoarseSpace_Private(PC pc, PetscInt l, DM dm, KSP smooth, PetscInt Nc, Mat guess, Mat *cspace)
217: {
218:   KSP            *sksp;
219:   Mat             A, *sA_IG, *sGf, preallocator;
220:   IS              Gidx, GidxMult, cG;
221:   IS             *sI, *sG, *sGi, *sGiM;
222:   const PetscInt *cidx;
223:   PetscInt        NG, ns, n, i, c, rbs, cbs[2];
224:   PetscBool       flg;
225:   MatType         ptype;

227:   PetscFunctionBegin;
228:   *cspace = NULL;
229:   if (!l) PetscFunctionReturn(PETSC_SUCCESS);
230:   if (pc->useAmat) {
231:     PetscCall(KSPGetOperatorsSet(smooth, &flg, NULL));
232:     PetscCheck(flg, PetscObjectComm((PetscObject)smooth), PETSC_ERR_ORDER, "Amat not set");
233:     PetscCall(KSPGetOperators(smooth, &A, NULL));
234:   } else {
235:     PetscCall(KSPGetOperatorsSet(smooth, NULL, &flg));
236:     PetscCheck(flg, PetscObjectComm((PetscObject)smooth), PETSC_ERR_ORDER, "Pmat not set");
237:     PetscCall(KSPGetOperators(smooth, NULL, &A));
238:   }

240:   /* Setup (also setup smoother here) */
241:   if (!pc->setupcalled) PetscCall(KSPSetFromOptions(smooth));
242:   PetscCall(KSPSetUp(smooth));
243:   PetscCall(KSPSetUpOnBlocks(smooth));
244:   PetscCall(PCMGGDSWSetUp(pc, l, dm, smooth, Nc, A, &ns, &sA_IG, &sksp, &sI, &sG, &sGf, &sGi, &sGiM));

246:   /* Number GDSW basis functions */
247:   PetscCall(ISConcatenate(PetscObjectComm((PetscObject)A), ns, sGi, &Gidx));
248:   PetscCall(ISConcatenate(PetscObjectComm((PetscObject)A), ns, sGiM, &GidxMult));
249:   PetscCall(ISRenumber(Gidx, GidxMult, &NG, &cG));
250:   PetscCall(ISDestroy(&Gidx));

252:   /* Detect column block size */
253:   PetscCall(ISGetMinMax(GidxMult, &cbs[0], &cbs[1]));
254:   PetscCall(PetscGlobalMinMaxInt(PetscObjectComm((PetscObject)A), cbs, cbs));
255:   PetscCall(ISDestroy(&GidxMult));

257:   /* Construct global interpolation matrix */
258:   PetscCall(MatGetLocalSize(A, NULL, &n));
259:   PetscCall(MatCreate(PetscObjectComm((PetscObject)A), &preallocator));
260:   PetscCall(MatSetSizes(preallocator, n, PETSC_DECIDE, PETSC_DECIDE, NG));
261:   PetscCall(MatSetType(preallocator, MATPREALLOCATOR));
262:   PetscCall(MatSetUp(preallocator));
263:   PetscCall(ISGetIndices(cG, &cidx));
264:   for (i = 0, c = 0; i < ns; i++) {
265:     const PetscInt *ri, *rg;
266:     PetscInt        nri, nrg, ncg;

268:     PetscCall(ISGetLocalSize(sI[i], &nri));
269:     PetscCall(ISGetLocalSize(sG[i], &nrg));
270:     PetscCall(ISGetIndices(sI[i], &ri));
271:     PetscCall(ISGetIndices(sG[i], &rg));
272:     PetscCall(MatGetSize(sGf[i], NULL, &ncg));
273:     PetscCall(MatSetValues(preallocator, nri, ri, ncg, cidx + c, NULL, INSERT_VALUES));
274:     PetscCall(MatSetValues(preallocator, nrg, rg, ncg, cidx + c, NULL, INSERT_VALUES));
275:     PetscCall(ISRestoreIndices(sI[i], &ri));
276:     PetscCall(ISRestoreIndices(sG[i], &rg));
277:   }
278:   PetscCall(MatAssemblyBegin(preallocator, MAT_FINAL_ASSEMBLY));
279:   PetscCall(MatAssemblyEnd(preallocator, MAT_FINAL_ASSEMBLY));

281:   ptype = MATAIJ;
282:   if (PetscDefined(HAVE_DEVICE)) {
283:     PetscCall(MatBoundToCPU(A, &flg));
284:     if (!flg) {
285:       VecType vtype;
286:       char   *found = NULL;

288:       PetscCall(MatGetVecType(A, &vtype));
289:       PetscCall(PetscStrstr(vtype, "cuda", &found));
290:       if (found) ptype = MATAIJCUSPARSE;
291:     }
292:   }
293:   PetscCall(MatCreate(PetscObjectComm((PetscObject)A), cspace));
294:   PetscCall(MatSetSizes(*cspace, n, PETSC_DECIDE, PETSC_DECIDE, NG));
295:   PetscCall(MatSetType(*cspace, ptype));
296:   PetscCall(MatGetBlockSizes(A, NULL, &rbs));
297:   PetscCall(MatSetBlockSizes(*cspace, rbs, cbs[0] == cbs[1] ? cbs[0] : 1));
298:   PetscCall(MatPreallocatorPreallocate(preallocator, PETSC_FALSE, *cspace));
299:   PetscCall(MatDestroy(&preallocator));
300:   PetscCall(MatSetOption(*cspace, MAT_ROW_ORIENTED, PETSC_FALSE));

302:   for (i = 0, c = 0; i < ns; i++) {
303:     Mat                X, Y;
304:     const PetscScalar *v;
305:     const PetscInt    *ri, *rg;
306:     PetscInt           nri, nrg, ncg;

308:     PetscCall(MatMatMult(sA_IG[i], sGf[i], MAT_INITIAL_MATRIX, PETSC_DEFAULT, &Y));
309:     PetscCall(MatScale(Y, -1.0));
310:     PetscCall(MatDuplicate(Y, MAT_DO_NOT_COPY_VALUES, &X));
311:     PetscCall(KSPMatSolve(sksp[i], Y, X));

313:     PetscCall(ISGetLocalSize(sI[i], &nri));
314:     PetscCall(ISGetLocalSize(sG[i], &nrg));
315:     PetscCall(ISGetIndices(sI[i], &ri));
316:     PetscCall(ISGetIndices(sG[i], &rg));
317:     PetscCall(MatGetSize(sGf[i], NULL, &ncg));

319:     PetscCall(MatDenseGetArrayRead(X, &v));
320:     PetscCall(MatSetValues(*cspace, nri, ri, ncg, cidx + c, v, INSERT_VALUES));
321:     PetscCall(MatDenseRestoreArrayRead(X, &v));
322:     PetscCall(MatDenseGetArrayRead(sGf[i], &v));
323:     PetscCall(MatSetValues(*cspace, nrg, rg, ncg, cidx + c, v, INSERT_VALUES));
324:     PetscCall(MatDenseRestoreArrayRead(sGf[i], &v));
325:     PetscCall(ISRestoreIndices(sI[i], &ri));
326:     PetscCall(ISRestoreIndices(sG[i], &rg));
327:     PetscCall(MatDestroy(&Y));
328:     PetscCall(MatDestroy(&X));
329:   }
330:   PetscCall(ISRestoreIndices(cG, &cidx));
331:   PetscCall(ISDestroy(&cG));
332:   PetscCall(MatAssemblyBegin(*cspace, MAT_FINAL_ASSEMBLY));
333:   PetscCall(MatAssemblyEnd(*cspace, MAT_FINAL_ASSEMBLY));

335:   for (i = 0; i < ns; i++) {
336:     PetscCall(KSPDestroy(&sksp[i]));
337:     PetscCall(ISDestroy(&sI[i]));
338:     PetscCall(ISDestroy(&sG[i]));
339:     PetscCall(ISDestroy(&sGi[i]));
340:     PetscCall(ISDestroy(&sGiM[i]));
341:     PetscCall(MatDestroy(&sGf[i]));
342:     PetscCall(MatDestroy(&sA_IG[i]));
343:   }
344:   PetscCall(PetscFree(sksp));
345:   PetscCall(PetscFree(sI));
346:   PetscCall(PetscFree(sG));
347:   PetscCall(PetscFree(sGi));
348:   PetscCall(PetscFree(sGiM));
349:   PetscCall(PetscFree(sGf));
350:   PetscCall(PetscFree(sA_IG));
351:   PetscFunctionReturn(PETSC_SUCCESS);
352: }