Actual source code: bddcgraph.c

  1: #include <petsc/private/petscimpl.h>
  2: #include <petsc/private/pcbddcprivateimpl.h>
  3: #include <petsc/private/pcbddcstructsimpl.h>

  5: PetscErrorCode PCBDDCDestroyGraphCandidatesIS(void *ctx)
  6: {
  7:   PCBDDCGraphCandidates cand = (PCBDDCGraphCandidates)ctx;

  9:   PetscFunctionBegin;
 10:   for (PetscInt i = 0; i < cand->nfc; i++) PetscCall(ISDestroy(&cand->Faces[i]));
 11:   for (PetscInt i = 0; i < cand->nec; i++) PetscCall(ISDestroy(&cand->Edges[i]));
 12:   PetscCall(PetscFree(cand->Faces));
 13:   PetscCall(PetscFree(cand->Edges));
 14:   PetscCall(ISDestroy(&cand->Vertices));
 15:   PetscCall(PetscFree(cand));
 16:   PetscFunctionReturn(PETSC_SUCCESS);
 17: }

 19: PetscErrorCode PCBDDCGraphGetDirichletDofsB(PCBDDCGraph graph, IS *dirdofs)
 20: {
 21:   PetscFunctionBegin;
 22:   if (graph->dirdofsB) {
 23:     PetscCall(PetscObjectReference((PetscObject)graph->dirdofsB));
 24:   } else if (graph->has_dirichlet) {
 25:     PetscInt  i, size;
 26:     PetscInt *dirdofs_idxs;

 28:     size = 0;
 29:     for (i = 0; i < graph->nvtxs; i++) {
 30:       if (graph->count[i] && graph->special_dof[i] == PCBDDCGRAPH_DIRICHLET_MARK) size++;
 31:     }

 33:     PetscCall(PetscMalloc1(size, &dirdofs_idxs));
 34:     size = 0;
 35:     for (i = 0; i < graph->nvtxs; i++) {
 36:       if (graph->count[i] && graph->special_dof[i] == PCBDDCGRAPH_DIRICHLET_MARK) dirdofs_idxs[size++] = i;
 37:     }
 38:     PetscCall(ISCreateGeneral(PETSC_COMM_SELF, size, dirdofs_idxs, PETSC_OWN_POINTER, &graph->dirdofsB));
 39:     PetscCall(PetscObjectReference((PetscObject)graph->dirdofsB));
 40:   }
 41:   *dirdofs = graph->dirdofsB;
 42:   PetscFunctionReturn(PETSC_SUCCESS);
 43: }

 45: PetscErrorCode PCBDDCGraphGetDirichletDofs(PCBDDCGraph graph, IS *dirdofs)
 46: {
 47:   PetscFunctionBegin;
 48:   if (graph->dirdofs) {
 49:     PetscCall(PetscObjectReference((PetscObject)graph->dirdofs));
 50:   } else if (graph->has_dirichlet) {
 51:     PetscInt  i, size;
 52:     PetscInt *dirdofs_idxs;

 54:     size = 0;
 55:     for (i = 0; i < graph->nvtxs; i++) {
 56:       if (graph->special_dof[i] == PCBDDCGRAPH_DIRICHLET_MARK) size++;
 57:     }

 59:     PetscCall(PetscMalloc1(size, &dirdofs_idxs));
 60:     size = 0;
 61:     for (i = 0; i < graph->nvtxs; i++) {
 62:       if (graph->special_dof[i] == PCBDDCGRAPH_DIRICHLET_MARK) dirdofs_idxs[size++] = i;
 63:     }
 64:     PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)graph->l2gmap), size, dirdofs_idxs, PETSC_OWN_POINTER, &graph->dirdofs));
 65:     PetscCall(PetscObjectReference((PetscObject)graph->dirdofs));
 66:   }
 67:   *dirdofs = graph->dirdofs;
 68:   PetscFunctionReturn(PETSC_SUCCESS);
 69: }

 71: PetscErrorCode PCBDDCGraphASCIIView(PCBDDCGraph graph, PetscInt verbosity_level, PetscViewer viewer)
 72: {
 73:   PetscInt  i, j, tabs;
 74:   PetscInt *queue_in_global_numbering;

 76:   PetscFunctionBegin;
 77:   PetscCall(PetscViewerASCIIPushSynchronized(viewer));
 78:   PetscCall(PetscViewerASCIIGetTab(viewer, &tabs));
 79:   PetscCall(PetscViewerASCIIPrintf(viewer, "--------------------------------------------------\n"));
 80:   PetscCall(PetscViewerFlush(viewer));
 81:   PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "Local BDDC graph for subdomain %04d\n", PetscGlobalRank));
 82:   PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "Number of vertices %" PetscInt_FMT "\n", graph->nvtxs));
 83:   PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "Number of local subdomains %" PetscInt_FMT "\n", graph->n_local_subs ? graph->n_local_subs : 1));
 84:   PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "Custom minimal size %" PetscInt_FMT "\n", graph->custom_minimal_size));
 85:   if (graph->maxcount != PETSC_MAX_INT) PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "Max count %" PetscInt_FMT "\n", graph->maxcount));
 86:   PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "Topological two dim? %s (set %s)\n", PetscBools[graph->twodim], PetscBools[graph->twodimset]));
 87:   if (verbosity_level > 2) {
 88:     for (i = 0; i < graph->nvtxs; i++) {
 89:       PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "%" PetscInt_FMT ":\n", i));
 90:       PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "   which_dof: %" PetscInt_FMT "\n", graph->which_dof[i]));
 91:       PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "   special_dof: %" PetscInt_FMT "\n", graph->special_dof[i]));
 92:       PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "   neighbours: %" PetscInt_FMT "\n", graph->count[i]));
 93:       PetscCall(PetscViewerASCIIUseTabs(viewer, PETSC_FALSE));
 94:       if (graph->count[i]) {
 95:         PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "     set of neighbours:"));
 96:         for (j = 0; j < graph->count[i]; j++) PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, " %" PetscInt_FMT, graph->neighbours_set[i][j]));
 97:         PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "\n"));
 98:       }
 99:       PetscCall(PetscViewerASCIISetTab(viewer, tabs));
100:       PetscCall(PetscViewerASCIIUseTabs(viewer, PETSC_TRUE));
101:       if (graph->mirrors) {
102:         PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "   mirrors: %" PetscInt_FMT "\n", graph->mirrors[i]));
103:         if (graph->mirrors[i]) {
104:           PetscCall(PetscViewerASCIIUseTabs(viewer, PETSC_FALSE));
105:           PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "     set of mirrors:"));
106:           for (j = 0; j < graph->mirrors[i]; j++) PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, " %" PetscInt_FMT, graph->mirrors_set[i][j]));
107:           PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "\n"));
108:           PetscCall(PetscViewerASCIISetTab(viewer, tabs));
109:           PetscCall(PetscViewerASCIIUseTabs(viewer, PETSC_TRUE));
110:         }
111:       }
112:       if (verbosity_level > 3) {
113:         if (graph->xadj) {
114:           PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "   local adj list:"));
115:           PetscCall(PetscViewerASCIIUseTabs(viewer, PETSC_FALSE));
116:           for (j = graph->xadj[i]; j < graph->xadj[i + 1]; j++) PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, " %" PetscInt_FMT, graph->adjncy[j]));
117:           PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "\n"));
118:           PetscCall(PetscViewerASCIISetTab(viewer, tabs));
119:           PetscCall(PetscViewerASCIIUseTabs(viewer, PETSC_TRUE));
120:         } else {
121:           PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "   no adj info\n"));
122:         }
123:       }
124:       if (graph->n_local_subs) PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "   local sub id: %" PetscInt_FMT "\n", graph->local_subs[i]));
125:       PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "   interface subset id: %" PetscInt_FMT "\n", graph->subset[i]));
126:       if (graph->subset[i] && graph->subset_ncc) PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "   ncc for subset: %" PetscInt_FMT "\n", graph->subset_ncc[graph->subset[i] - 1]));
127:     }
128:   }
129:   PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "Total number of connected components %" PetscInt_FMT "\n", graph->ncc));
130:   PetscCall(PetscMalloc1(graph->cptr[graph->ncc], &queue_in_global_numbering));
131:   PetscCall(ISLocalToGlobalMappingApply(graph->l2gmap, graph->cptr[graph->ncc], graph->queue, queue_in_global_numbering));
132:   for (i = 0; i < graph->ncc; i++) {
133:     PetscInt  node_num = graph->queue[graph->cptr[i]];
134:     PetscBool printcc  = PETSC_FALSE;
135:     PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "  cc %" PetscInt_FMT " (size %" PetscInt_FMT ", fid %" PetscInt_FMT ", neighs:", i, graph->cptr[i + 1] - graph->cptr[i], graph->which_dof[node_num]));
136:     PetscCall(PetscViewerASCIIUseTabs(viewer, PETSC_FALSE));
137:     for (j = 0; j < graph->count[node_num]; j++) PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, " %" PetscInt_FMT, graph->neighbours_set[node_num][j]));
138:     if (verbosity_level > 1) {
139:       PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "):"));
140:       if (verbosity_level > 2 || graph->twodim || graph->count[node_num] > 1 || (graph->count[node_num] == 1 && graph->special_dof[node_num] == PCBDDCGRAPH_NEUMANN_MARK)) printcc = PETSC_TRUE;
141:       if (printcc) {
142:         for (j = graph->cptr[i]; j < graph->cptr[i + 1]; j++) PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, " %" PetscInt_FMT " (%" PetscInt_FMT ")", graph->queue[j], queue_in_global_numbering[j]));
143:       }
144:     } else {
145:       PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, ")"));
146:     }
147:     PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "\n"));
148:     PetscCall(PetscViewerASCIISetTab(viewer, tabs));
149:     PetscCall(PetscViewerASCIIUseTabs(viewer, PETSC_TRUE));
150:   }
151:   PetscCall(PetscFree(queue_in_global_numbering));
152:   PetscCall(PetscViewerFlush(viewer));
153:   PetscFunctionReturn(PETSC_SUCCESS);
154: }

156: PetscErrorCode PCBDDCGraphRestoreCandidatesIS(PCBDDCGraph graph, PetscInt *n_faces, IS *FacesIS[], PetscInt *n_edges, IS *EdgesIS[], IS *VerticesIS)
157: {
158:   PetscInt       i;
159:   PetscContainer gcand;

161:   PetscFunctionBegin;
162:   PetscCall(PetscObjectQuery((PetscObject)graph->l2gmap, "_PCBDDCGraphCandidatesIS", (PetscObject *)&gcand));
163:   if (gcand) {
164:     if (n_faces) *n_faces = 0;
165:     if (n_edges) *n_edges = 0;
166:     if (FacesIS) *FacesIS = NULL;
167:     if (EdgesIS) *EdgesIS = NULL;
168:     if (VerticesIS) *VerticesIS = NULL;
169:   }
170:   if (n_faces) {
171:     if (FacesIS) {
172:       for (i = 0; i < *n_faces; i++) PetscCall(ISDestroy(&((*FacesIS)[i])));
173:       PetscCall(PetscFree(*FacesIS));
174:     }
175:     *n_faces = 0;
176:   }
177:   if (n_edges) {
178:     if (EdgesIS) {
179:       for (i = 0; i < *n_edges; i++) PetscCall(ISDestroy(&((*EdgesIS)[i])));
180:       PetscCall(PetscFree(*EdgesIS));
181:     }
182:     *n_edges = 0;
183:   }
184:   if (VerticesIS) PetscCall(ISDestroy(VerticesIS));
185:   PetscFunctionReturn(PETSC_SUCCESS);
186: }

188: PetscErrorCode PCBDDCGraphGetCandidatesIS(PCBDDCGraph graph, PetscInt *n_faces, IS *FacesIS[], PetscInt *n_edges, IS *EdgesIS[], IS *VerticesIS)
189: {
190:   IS            *ISForFaces, *ISForEdges, ISForVertices;
191:   PetscInt       i, nfc, nec, nvc, *idx, *mark;
192:   PetscContainer gcand;

194:   PetscFunctionBegin;
195:   PetscCall(PetscObjectQuery((PetscObject)graph->l2gmap, "_PCBDDCGraphCandidatesIS", (PetscObject *)&gcand));
196:   if (gcand) {
197:     PCBDDCGraphCandidates cand;

199:     PetscCall(PetscContainerGetPointer(gcand, (void **)&cand));
200:     if (n_faces) *n_faces = cand->nfc;
201:     if (FacesIS) *FacesIS = cand->Faces;
202:     if (n_edges) *n_edges = cand->nec;
203:     if (EdgesIS) *EdgesIS = cand->Edges;
204:     if (VerticesIS) *VerticesIS = cand->Vertices;
205:     PetscFunctionReturn(PETSC_SUCCESS);
206:   }
207:   PetscCall(PetscCalloc1(graph->ncc, &mark));
208:   /* loop on ccs to evaluate number of faces, edges and vertices */
209:   nfc = 0;
210:   nec = 0;
211:   nvc = 0;
212:   for (i = 0; i < graph->ncc; i++) {
213:     PetscInt repdof = graph->queue[graph->cptr[i]];
214:     if (graph->cptr[i + 1] - graph->cptr[i] > graph->custom_minimal_size && graph->count[repdof] < graph->maxcount) {
215:       if (!graph->twodim && graph->count[repdof] == 1 && graph->special_dof[repdof] != PCBDDCGRAPH_NEUMANN_MARK) {
216:         nfc++;
217:         mark[i] = 2;
218:       } else {
219:         nec++;
220:         mark[i] = 1;
221:       }
222:     } else {
223:       nvc += graph->cptr[i + 1] - graph->cptr[i];
224:     }
225:   }

227:   /* allocate IS arrays for faces, edges. Vertices need a single index set. */
228:   if (FacesIS) PetscCall(PetscMalloc1(nfc, &ISForFaces));
229:   if (EdgesIS) PetscCall(PetscMalloc1(nec, &ISForEdges));
230:   if (VerticesIS) PetscCall(PetscMalloc1(nvc, &idx));

232:   /* loop on ccs to compute index sets for faces and edges */
233:   if (!graph->queue_sorted) {
234:     PetscInt *queue_global;

236:     PetscCall(PetscMalloc1(graph->cptr[graph->ncc], &queue_global));
237:     PetscCall(ISLocalToGlobalMappingApply(graph->l2gmap, graph->cptr[graph->ncc], graph->queue, queue_global));
238:     for (i = 0; i < graph->ncc; i++) PetscCall(PetscSortIntWithArray(graph->cptr[i + 1] - graph->cptr[i], &queue_global[graph->cptr[i]], &graph->queue[graph->cptr[i]]));
239:     PetscCall(PetscFree(queue_global));
240:     graph->queue_sorted = PETSC_TRUE;
241:   }
242:   nfc = 0;
243:   nec = 0;
244:   for (i = 0; i < graph->ncc; i++) {
245:     if (mark[i] == 2) {
246:       if (FacesIS) PetscCall(ISCreateGeneral(PETSC_COMM_SELF, graph->cptr[i + 1] - graph->cptr[i], &graph->queue[graph->cptr[i]], PETSC_USE_POINTER, &ISForFaces[nfc]));
247:       nfc++;
248:     } else if (mark[i] == 1) {
249:       if (EdgesIS) PetscCall(ISCreateGeneral(PETSC_COMM_SELF, graph->cptr[i + 1] - graph->cptr[i], &graph->queue[graph->cptr[i]], PETSC_USE_POINTER, &ISForEdges[nec]));
250:       nec++;
251:     }
252:   }

254:   /* index set for vertices */
255:   if (VerticesIS) {
256:     nvc = 0;
257:     for (i = 0; i < graph->ncc; i++) {
258:       if (!mark[i]) {
259:         PetscInt j;

261:         for (j = graph->cptr[i]; j < graph->cptr[i + 1]; j++) {
262:           idx[nvc] = graph->queue[j];
263:           nvc++;
264:         }
265:       }
266:     }
267:     /* sort vertex set (by local ordering) */
268:     PetscCall(PetscSortInt(nvc, idx));
269:     PetscCall(ISCreateGeneral(PETSC_COMM_SELF, nvc, idx, PETSC_OWN_POINTER, &ISForVertices));
270:   }
271:   PetscCall(PetscFree(mark));

273:   /* get back info */
274:   if (n_faces) *n_faces = nfc;
275:   if (FacesIS) *FacesIS = ISForFaces;
276:   if (n_edges) *n_edges = nec;
277:   if (EdgesIS) *EdgesIS = ISForEdges;
278:   if (VerticesIS) *VerticesIS = ISForVertices;
279:   PetscFunctionReturn(PETSC_SUCCESS);
280: }

282: PetscErrorCode PCBDDCGraphComputeConnectedComponents(PCBDDCGraph graph)
283: {
284:   PetscBool   adapt_interface_reduced;
285:   MPI_Comm    interface_comm;
286:   PetscMPIInt size;
287:   PetscInt    i;
288:   PetscBT     cornerp;

290:   PetscFunctionBegin;
291:   /* compute connected components locally */
292:   PetscCall(PetscObjectGetComm((PetscObject)(graph->l2gmap), &interface_comm));
293:   PetscCall(PCBDDCGraphComputeConnectedComponentsLocal(graph));

295:   cornerp = NULL;
296:   if (graph->active_coords) { /* face based corner selection */
297:     PetscBT    excluded;
298:     PetscReal *wdist;
299:     PetscInt   n_neigh, *neigh, *n_shared, **shared;
300:     PetscInt   maxc, ns;

302:     PetscCall(PetscBTCreate(graph->nvtxs, &cornerp));
303:     PetscCall(ISLocalToGlobalMappingGetInfo(graph->l2gmap, &n_neigh, &neigh, &n_shared, &shared));
304:     for (ns = 1, maxc = 0; ns < n_neigh; ns++) maxc = PetscMax(maxc, n_shared[ns]);
305:     PetscCall(PetscMalloc1(maxc * graph->cdim, &wdist));
306:     PetscCall(PetscBTCreate(maxc, &excluded));

308:     for (ns = 1; ns < n_neigh; ns++) { /* first proc is self */
309:       PetscReal *anchor, mdist;
310:       PetscInt   fst, j, k, d, cdim = graph->cdim, n = n_shared[ns];
311:       PetscInt   point1, point2, point3, point4;

313:       /* import coordinates on shared interface */
314:       PetscCall(PetscBTMemzero(n, excluded));
315:       for (j = 0, fst = -1, k = 0; j < n; j++) {
316:         PetscBool skip = PETSC_FALSE;
317:         for (d = 0; d < cdim; d++) {
318:           PetscReal c = graph->coords[shared[ns][j] * cdim + d];
319:           skip        = (PetscBool)(skip || c == PETSC_MAX_REAL);
320:           wdist[k++]  = c;
321:         }
322:         if (skip) {
323:           PetscCall(PetscBTSet(excluded, j));
324:         } else if (fst == -1) fst = j;
325:       }
326:       if (fst == -1) continue;

328:       /* the dofs are sorted by global numbering, so each rank starts from the same id
329:          and it will detect the same corners from the given set */

331:       /* find the farthest point from the starting one */
332:       anchor = wdist + fst * cdim;
333:       mdist  = -1.0;
334:       point1 = fst;
335:       for (j = fst; j < n; j++) {
336:         PetscReal dist = 0.0;

338:         if (PetscUnlikely(PetscBTLookup(excluded, j))) continue;
339:         for (d = 0; d < cdim; d++) dist += (wdist[j * cdim + d] - anchor[d]) * (wdist[j * cdim + d] - anchor[d]);
340:         if (dist > mdist) {
341:           mdist  = dist;
342:           point1 = j;
343:         }
344:       }

346:       /* find the farthest point from point1 */
347:       anchor = wdist + point1 * cdim;
348:       mdist  = -1.0;
349:       point2 = point1;
350:       for (j = fst; j < n; j++) {
351:         PetscReal dist = 0.0;

353:         if (PetscUnlikely(PetscBTLookup(excluded, j))) continue;
354:         for (d = 0; d < cdim; d++) dist += (wdist[j * cdim + d] - anchor[d]) * (wdist[j * cdim + d] - anchor[d]);
355:         if (dist > mdist) {
356:           mdist  = dist;
357:           point2 = j;
358:         }
359:       }

361:       /* find the third point maximizing the triangle area */
362:       point3 = point2;
363:       if (cdim > 2) {
364:         PetscReal a = 0.0;

366:         for (d = 0; d < cdim; d++) a += (wdist[point1 * cdim + d] - wdist[point2 * cdim + d]) * (wdist[point1 * cdim + d] - wdist[point2 * cdim + d]);
367:         a     = PetscSqrtReal(a);
368:         mdist = -1.0;
369:         for (j = fst; j < n; j++) {
370:           PetscReal area, b = 0.0, c = 0.0, s;

372:           if (PetscUnlikely(PetscBTLookup(excluded, j))) continue;
373:           for (d = 0; d < cdim; d++) {
374:             b += (wdist[point1 * cdim + d] - wdist[j * cdim + d]) * (wdist[point1 * cdim + d] - wdist[j * cdim + d]);
375:             c += (wdist[point2 * cdim + d] - wdist[j * cdim + d]) * (wdist[point2 * cdim + d] - wdist[j * cdim + d]);
376:           }
377:           b = PetscSqrtReal(b);
378:           c = PetscSqrtReal(c);
379:           s = 0.5 * (a + b + c);

381:           /* Heron's formula, area squared */
382:           area = s * (s - a) * (s - b) * (s - c);
383:           if (area > mdist) {
384:             mdist  = area;
385:             point3 = j;
386:           }
387:         }
388:       }

390:       /* find the farthest point from point3 different from point1 and point2 */
391:       anchor = wdist + point3 * cdim;
392:       mdist  = -1.0;
393:       point4 = point3;
394:       for (j = fst; j < n; j++) {
395:         PetscReal dist = 0.0;

397:         if (PetscUnlikely(PetscBTLookup(excluded, j)) || j == point1 || j == point2 || j == point3) continue;
398:         for (d = 0; d < cdim; d++) dist += (wdist[j * cdim + d] - anchor[d]) * (wdist[j * cdim + d] - anchor[d]);
399:         if (dist > mdist) {
400:           mdist  = dist;
401:           point4 = j;
402:         }
403:       }

405:       PetscCall(PetscBTSet(cornerp, shared[ns][point1]));
406:       PetscCall(PetscBTSet(cornerp, shared[ns][point2]));
407:       PetscCall(PetscBTSet(cornerp, shared[ns][point3]));
408:       PetscCall(PetscBTSet(cornerp, shared[ns][point4]));

410:       /* all dofs having the same coordinates will be primal */
411:       for (j = fst; j < n; j++) {
412:         PetscBool same[] = {PETSC_TRUE, PETSC_TRUE, PETSC_TRUE, PETSC_TRUE};

414:         if (PetscUnlikely(PetscBTLookup(excluded, j))) continue;
415:         for (d = 0; d < cdim; d++) {
416:           same[0] = (PetscBool)(same[0] && (PetscAbsReal(wdist[j * cdim + d] - wdist[point1 * cdim + d]) < PETSC_SMALL));
417:           same[1] = (PetscBool)(same[1] && (PetscAbsReal(wdist[j * cdim + d] - wdist[point2 * cdim + d]) < PETSC_SMALL));
418:           same[2] = (PetscBool)(same[2] && (PetscAbsReal(wdist[j * cdim + d] - wdist[point3 * cdim + d]) < PETSC_SMALL));
419:           same[3] = (PetscBool)(same[3] && (PetscAbsReal(wdist[j * cdim + d] - wdist[point4 * cdim + d]) < PETSC_SMALL));
420:         }
421:         if (same[0] || same[1] || same[2] || same[3]) PetscCall(PetscBTSet(cornerp, shared[ns][j]));
422:       }
423:     }
424:     PetscCall(PetscBTDestroy(&excluded));
425:     PetscCall(PetscFree(wdist));
426:     PetscCall(ISLocalToGlobalMappingRestoreInfo(graph->l2gmap, &n_neigh, &neigh, &n_shared, &shared));
427:   }

429:   /* check consistency of connected components among neighbouring subdomains -> it adapt them in case it is needed */
430:   PetscCallMPI(MPI_Comm_size(interface_comm, &size));
431:   adapt_interface_reduced = PETSC_FALSE;
432:   if (size > 1) {
433:     PetscInt  i;
434:     PetscBool adapt_interface = cornerp ? PETSC_TRUE : PETSC_FALSE;
435:     for (i = 0; i < graph->n_subsets && !adapt_interface; i++) {
436:       /* We are not sure that on a given subset of the local interface,
437:          with two connected components, the latters be the same among sharing subdomains */
438:       if (graph->subset_ncc[i] > 1) adapt_interface = PETSC_TRUE;
439:     }
440:     PetscCall(MPIU_Allreduce(&adapt_interface, &adapt_interface_reduced, 1, MPIU_BOOL, MPI_LOR, interface_comm));
441:   }

443:   if (graph->n_subsets && adapt_interface_reduced) {
444:     PetscBT      subset_cc_adapt;
445:     MPI_Request *send_requests, *recv_requests;
446:     PetscInt    *send_buffer, *recv_buffer;
447:     PetscInt     sum_requests, start_of_recv, start_of_send;
448:     PetscInt    *cum_recv_counts;
449:     PetscInt    *labels;
450:     PetscInt     ncc, cum_queue, mss, mns, j, k, s;
451:     PetscInt   **refine_buffer = NULL, *private_labels = NULL;
452:     PetscBool   *subset_has_corn, *recv_buffer_bool, *send_buffer_bool;

454:     PetscCall(PetscCalloc1(graph->n_subsets, &subset_has_corn));
455:     if (cornerp) {
456:       for (i = 0; i < graph->n_subsets; i++) {
457:         for (j = 0; j < graph->subset_size[i]; j++) {
458:           if (PetscBTLookup(cornerp, graph->subset_idxs[i][j])) {
459:             subset_has_corn[i] = PETSC_TRUE;
460:             break;
461:           }
462:         }
463:       }
464:     }
465:     PetscCall(PetscMalloc1(graph->nvtxs, &labels));
466:     PetscCall(PetscArrayzero(labels, graph->nvtxs));
467:     for (i = 0, k = 0; i < graph->ncc; i++) {
468:       PetscInt s = 1;
469:       for (j = graph->cptr[i]; j < graph->cptr[i + 1]; j++) {
470:         if (cornerp && PetscBTLookup(cornerp, graph->queue[j])) {
471:           labels[graph->queue[j]] = k + s;
472:           s += 1;
473:         } else {
474:           labels[graph->queue[j]] = k;
475:         }
476:       }
477:       k += s;
478:     }

480:     /* allocate some space */
481:     PetscCall(PetscMalloc1(graph->n_subsets + 1, &cum_recv_counts));
482:     PetscCall(PetscArrayzero(cum_recv_counts, graph->n_subsets + 1));

484:     /* first count how many neighbours per connected component I will receive from */
485:     cum_recv_counts[0] = 0;
486:     for (i = 0; i < graph->n_subsets; i++) cum_recv_counts[i + 1] = cum_recv_counts[i] + graph->count[graph->subset_idxs[i][0]];
487:     PetscCall(PetscMalloc1(graph->n_subsets, &send_buffer_bool));
488:     PetscCall(PetscMalloc1(cum_recv_counts[graph->n_subsets], &recv_buffer_bool));
489:     PetscCall(PetscMalloc2(cum_recv_counts[graph->n_subsets], &send_requests, cum_recv_counts[graph->n_subsets], &recv_requests));
490:     for (i = 0; i < cum_recv_counts[graph->n_subsets]; i++) {
491:       send_requests[i] = MPI_REQUEST_NULL;
492:       recv_requests[i] = MPI_REQUEST_NULL;
493:     }

495:     /* exchange with my neighbours the number of my connected components on the subset of interface */
496:     sum_requests = 0;
497:     for (i = 0; i < graph->n_subsets; i++) send_buffer_bool[i] = (PetscBool)(graph->subset_ncc[i] > 1 || subset_has_corn[i]);
498:     for (i = 0; i < graph->n_subsets; i++) {
499:       PetscMPIInt neigh, tag;
500:       PetscInt    count, *neighs;

502:       count  = graph->count[graph->subset_idxs[i][0]];
503:       neighs = graph->neighbours_set[graph->subset_idxs[i][0]];
504:       PetscCall(PetscMPIIntCast(2 * graph->subset_ref_node[i], &tag));
505:       for (k = 0; k < count; k++) {
506:         PetscCall(PetscMPIIntCast(neighs[k], &neigh));
507:         PetscCallMPI(MPI_Isend(send_buffer_bool + i, 1, MPIU_BOOL, neigh, tag, interface_comm, &send_requests[sum_requests]));
508:         PetscCallMPI(MPI_Irecv(recv_buffer_bool + sum_requests, 1, MPIU_BOOL, neigh, tag, interface_comm, &recv_requests[sum_requests]));
509:         sum_requests++;
510:       }
511:     }
512:     PetscCallMPI(MPI_Waitall(sum_requests, recv_requests, MPI_STATUSES_IGNORE));
513:     PetscCallMPI(MPI_Waitall(sum_requests, send_requests, MPI_STATUSES_IGNORE));

515:     /* determine the subsets I have to adapt (those having more than 1 cc) */
516:     PetscCall(PetscBTCreate(graph->n_subsets, &subset_cc_adapt));
517:     PetscCall(PetscBTMemzero(graph->n_subsets, subset_cc_adapt));
518:     for (i = 0; i < graph->n_subsets; i++) {
519:       if (graph->subset_ncc[i] > 1 || subset_has_corn[i]) {
520:         PetscCall(PetscBTSet(subset_cc_adapt, i));
521:         continue;
522:       }
523:       for (j = cum_recv_counts[i]; j < cum_recv_counts[i + 1]; j++) {
524:         if (recv_buffer_bool[j]) {
525:           PetscCall(PetscBTSet(subset_cc_adapt, i));
526:           break;
527:         }
528:       }
529:     }
530:     PetscCall(PetscFree(send_buffer_bool));
531:     PetscCall(PetscFree(recv_buffer_bool));
532:     PetscCall(PetscFree(subset_has_corn));

534:     /* determine send/recv buffers sizes */
535:     j   = 0;
536:     mss = 0;
537:     for (i = 0; i < graph->n_subsets; i++) {
538:       if (PetscBTLookup(subset_cc_adapt, i)) {
539:         j += graph->subset_size[i];
540:         mss = PetscMax(graph->subset_size[i], mss);
541:       }
542:     }
543:     k   = 0;
544:     mns = 0;
545:     for (i = 0; i < graph->n_subsets; i++) {
546:       if (PetscBTLookup(subset_cc_adapt, i)) {
547:         k += (cum_recv_counts[i + 1] - cum_recv_counts[i]) * graph->subset_size[i];
548:         mns = PetscMax(cum_recv_counts[i + 1] - cum_recv_counts[i], mns);
549:       }
550:     }
551:     PetscCall(PetscMalloc2(j, &send_buffer, k, &recv_buffer));

553:     /* fill send buffer (order matters: subset_idxs ordered by global ordering) */
554:     j = 0;
555:     for (i = 0; i < graph->n_subsets; i++)
556:       if (PetscBTLookup(subset_cc_adapt, i))
557:         for (k = 0; k < graph->subset_size[i]; k++) send_buffer[j++] = labels[graph->subset_idxs[i][k]];

559:     /* now exchange the data */
560:     start_of_recv = 0;
561:     start_of_send = 0;
562:     sum_requests  = 0;
563:     for (i = 0; i < graph->n_subsets; i++) {
564:       if (PetscBTLookup(subset_cc_adapt, i)) {
565:         PetscMPIInt neigh, tag;
566:         PetscInt    size_of_send = graph->subset_size[i];

568:         j = graph->subset_idxs[i][0];
569:         PetscCall(PetscMPIIntCast(2 * graph->subset_ref_node[i] + 1, &tag));
570:         for (k = 0; k < graph->count[j]; k++) {
571:           PetscCall(PetscMPIIntCast(graph->neighbours_set[j][k], &neigh));
572:           PetscCallMPI(MPI_Isend(&send_buffer[start_of_send], size_of_send, MPIU_INT, neigh, tag, interface_comm, &send_requests[sum_requests]));
573:           PetscCallMPI(MPI_Irecv(&recv_buffer[start_of_recv], size_of_send, MPIU_INT, neigh, tag, interface_comm, &recv_requests[sum_requests]));
574:           start_of_recv += size_of_send;
575:           sum_requests++;
576:         }
577:         start_of_send += size_of_send;
578:       }
579:     }
580:     PetscCallMPI(MPI_Waitall(sum_requests, recv_requests, MPI_STATUSES_IGNORE));

582:     /* refine connected components */
583:     start_of_recv = 0;
584:     /* allocate some temporary space */
585:     if (mss) {
586:       PetscCall(PetscMalloc1(mss, &refine_buffer));
587:       PetscCall(PetscMalloc2(mss * (mns + 1), &refine_buffer[0], mss, &private_labels));
588:     }
589:     ncc            = 0;
590:     cum_queue      = 0;
591:     graph->cptr[0] = 0;
592:     for (i = 0; i < graph->n_subsets; i++) {
593:       if (PetscBTLookup(subset_cc_adapt, i)) {
594:         PetscInt subset_counter = 0;
595:         PetscInt sharingprocs   = cum_recv_counts[i + 1] - cum_recv_counts[i] + 1; /* count myself */
596:         PetscInt buffer_size    = graph->subset_size[i];

598:         /* compute pointers */
599:         for (j = 1; j < buffer_size; j++) refine_buffer[j] = refine_buffer[j - 1] + sharingprocs;
600:         /* analyze contributions from subdomains that share the i-th subset
601:            The structure of refine_buffer is suitable to find intersections of ccs among sharingprocs.
602:            supposing the current subset is shared by 3 processes and has dimension 5 with global dofs 0,1,2,3,4 (local 0,4,3,1,2)
603:            sharing procs connected components:
604:              neigh 0: [0 1 4], [2 3], labels [4,7]  (2 connected components)
605:              neigh 1: [0 1], [2 3 4], labels [3 2]  (2 connected components)
606:              neigh 2: [0 4], [1], [2 3], labels [1 5 6] (3 connected components)
607:            refine_buffer will be filled as:
608:              [ 4, 3, 1;
609:                4, 2, 1;
610:                7, 2, 6;
611:                4, 3, 5;
612:                7, 2, 6; ];
613:            The connected components in local ordering are [0], [1], [2 3], [4] */
614:         /* fill temp_buffer */
615:         for (k = 0; k < buffer_size; k++) refine_buffer[k][0] = labels[graph->subset_idxs[i][k]];
616:         for (j = 0; j < sharingprocs - 1; j++) {
617:           for (k = 0; k < buffer_size; k++) refine_buffer[k][j + 1] = recv_buffer[start_of_recv + k];
618:           start_of_recv += buffer_size;
619:         }
620:         PetscCall(PetscArrayzero(private_labels, buffer_size));
621:         for (j = 0; j < buffer_size; j++) {
622:           if (!private_labels[j]) { /* found a new cc  */
623:             PetscBool same_set;

625:             graph->cptr[ncc] = cum_queue;
626:             ncc++;
627:             subset_counter++;
628:             private_labels[j]         = subset_counter;
629:             graph->queue[cum_queue++] = graph->subset_idxs[i][j];
630:             for (k = j + 1; k < buffer_size; k++) { /* check for other nodes in new cc */
631:               same_set = PETSC_TRUE;
632:               for (s = 0; s < sharingprocs; s++) {
633:                 if (refine_buffer[j][s] != refine_buffer[k][s]) {
634:                   same_set = PETSC_FALSE;
635:                   break;
636:                 }
637:               }
638:               if (same_set) {
639:                 private_labels[k]         = subset_counter;
640:                 graph->queue[cum_queue++] = graph->subset_idxs[i][k];
641:               }
642:             }
643:           }
644:         }
645:         graph->cptr[ncc]     = cum_queue;
646:         graph->subset_ncc[i] = subset_counter;
647:         graph->queue_sorted  = PETSC_FALSE;
648:       } else { /* this subset does not need to be adapted */
649:         PetscCall(PetscArraycpy(graph->queue + cum_queue, graph->subset_idxs[i], graph->subset_size[i]));
650:         ncc++;
651:         cum_queue += graph->subset_size[i];
652:         graph->cptr[ncc] = cum_queue;
653:       }
654:     }
655:     graph->cptr[ncc] = cum_queue;
656:     graph->ncc       = ncc;
657:     if (mss) {
658:       PetscCall(PetscFree2(refine_buffer[0], private_labels));
659:       PetscCall(PetscFree(refine_buffer));
660:     }
661:     PetscCall(PetscFree(labels));
662:     PetscCallMPI(MPI_Waitall(sum_requests, send_requests, MPI_STATUSES_IGNORE));
663:     PetscCall(PetscFree2(send_requests, recv_requests));
664:     PetscCall(PetscFree2(send_buffer, recv_buffer));
665:     PetscCall(PetscFree(cum_recv_counts));
666:     PetscCall(PetscBTDestroy(&subset_cc_adapt));
667:   }
668:   PetscCall(PetscBTDestroy(&cornerp));

670:   /* Determine if we are in 2D or 3D */
671:   if (!graph->twodimset) {
672:     PetscBool twodim = PETSC_TRUE;
673:     for (i = 0; i < graph->ncc; i++) {
674:       PetscInt repdof = graph->queue[graph->cptr[i]];
675:       PetscInt ccsize = graph->cptr[i + 1] - graph->cptr[i];
676:       if (graph->count[repdof] > 1 && ccsize > graph->custom_minimal_size) {
677:         twodim = PETSC_FALSE;
678:         break;
679:       }
680:     }
681:     PetscCall(MPIU_Allreduce(&twodim, &graph->twodim, 1, MPIU_BOOL, MPI_LAND, PetscObjectComm((PetscObject)graph->l2gmap)));
682:     graph->twodimset = PETSC_TRUE;
683:   }
684:   PetscFunctionReturn(PETSC_SUCCESS);
685: }

687: static inline PetscErrorCode PCBDDCGraphComputeCC_Private(PCBDDCGraph graph, PetscInt pid, PetscInt *queue_tip, PetscInt n_prev, PetscInt *n_added)
688: {
689:   PetscInt  i, j, n;
690:   PetscInt *xadj = graph->xadj, *adjncy = graph->adjncy;
691:   PetscBT   touched  = graph->touched;
692:   PetscBool havecsr  = (PetscBool)(!!xadj);
693:   PetscBool havesubs = (PetscBool)(!!graph->n_local_subs);

695:   PetscFunctionBegin;
696:   n = 0;
697:   if (havecsr && !havesubs) {
698:     for (i = -n_prev; i < 0; i++) {
699:       PetscInt start_dof = queue_tip[i];
700:       /* we assume that if a dof has a size 1 adjacency list and the corresponding entry is negative, it is connected to all dofs */
701:       if (xadj[start_dof + 1] - xadj[start_dof] == 1 && adjncy[xadj[start_dof]] < 0) {
702:         for (j = 0; j < graph->subset_size[pid - 1]; j++) { /* pid \in [1,graph->n_subsets] */
703:           PetscInt dof = graph->subset_idxs[pid - 1][j];
704:           if (!PetscBTLookup(touched, dof) && graph->subset[dof] == pid) {
705:             PetscCall(PetscBTSet(touched, dof));
706:             queue_tip[n] = dof;
707:             n++;
708:           }
709:         }
710:       } else {
711:         for (j = xadj[start_dof]; j < xadj[start_dof + 1]; j++) {
712:           PetscInt dof = adjncy[j];
713:           if (!PetscBTLookup(touched, dof) && graph->subset[dof] == pid) {
714:             PetscCall(PetscBTSet(touched, dof));
715:             queue_tip[n] = dof;
716:             n++;
717:           }
718:         }
719:       }
720:     }
721:   } else if (havecsr && havesubs) {
722:     PetscInt sid = graph->local_subs[queue_tip[-n_prev]];
723:     for (i = -n_prev; i < 0; i++) {
724:       PetscInt start_dof = queue_tip[i];
725:       /* we assume that if a dof has a size 1 adjacency list and the corresponding entry is negative, it is connected to all dofs belonging to the local sub */
726:       if (xadj[start_dof + 1] - xadj[start_dof] == 1 && adjncy[xadj[start_dof]] < 0) {
727:         for (j = 0; j < graph->subset_size[pid - 1]; j++) { /* pid \in [1,graph->n_subsets] */
728:           PetscInt dof = graph->subset_idxs[pid - 1][j];
729:           if (!PetscBTLookup(touched, dof) && graph->subset[dof] == pid && graph->local_subs[dof] == sid) {
730:             PetscCall(PetscBTSet(touched, dof));
731:             queue_tip[n] = dof;
732:             n++;
733:           }
734:         }
735:       } else {
736:         for (j = xadj[start_dof]; j < xadj[start_dof + 1]; j++) {
737:           PetscInt dof = adjncy[j];
738:           if (!PetscBTLookup(touched, dof) && graph->subset[dof] == pid && graph->local_subs[dof] == sid) {
739:             PetscCall(PetscBTSet(touched, dof));
740:             queue_tip[n] = dof;
741:             n++;
742:           }
743:         }
744:       }
745:     }
746:   } else if (havesubs) { /* sub info only */
747:     PetscInt sid = graph->local_subs[queue_tip[-n_prev]];
748:     for (j = 0; j < graph->subset_size[pid - 1]; j++) { /* pid \in [1,graph->n_subsets] */
749:       PetscInt dof = graph->subset_idxs[pid - 1][j];
750:       if (!PetscBTLookup(touched, dof) && graph->subset[dof] == pid && graph->local_subs[dof] == sid) {
751:         PetscCall(PetscBTSet(touched, dof));
752:         queue_tip[n] = dof;
753:         n++;
754:       }
755:     }
756:   } else {
757:     for (j = 0; j < graph->subset_size[pid - 1]; j++) { /* pid \in [1,graph->n_subsets] */
758:       PetscInt dof = graph->subset_idxs[pid - 1][j];
759:       if (!PetscBTLookup(touched, dof) && graph->subset[dof] == pid) {
760:         PetscCall(PetscBTSet(touched, dof));
761:         queue_tip[n] = dof;
762:         n++;
763:       }
764:     }
765:   }
766:   *n_added = n;
767:   PetscFunctionReturn(PETSC_SUCCESS);
768: }

770: PetscErrorCode PCBDDCGraphComputeConnectedComponentsLocal(PCBDDCGraph graph)
771: {
772:   PetscInt    ncc, cum_queue, n;
773:   PetscMPIInt commsize;

775:   PetscFunctionBegin;
776:   PetscCheck(graph->setupcalled, PetscObjectComm((PetscObject)graph->l2gmap), PETSC_ERR_ORDER, "PCBDDCGraphSetUp should be called first");
777:   /* quiet return if there isn't any local info */
778:   if (!graph->xadj && !graph->n_local_subs) PetscFunctionReturn(PETSC_SUCCESS);

780:   /* reset any previous search of connected components */
781:   PetscCall(PetscBTMemzero(graph->nvtxs, graph->touched));
782:   PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)graph->l2gmap), &commsize));
783:   if (commsize > graph->commsizelimit) {
784:     PetscInt i;
785:     for (i = 0; i < graph->nvtxs; i++) {
786:       if (graph->special_dof[i] == PCBDDCGRAPH_DIRICHLET_MARK || !graph->count[i]) PetscCall(PetscBTSet(graph->touched, i));
787:     }
788:   }

790:   /* begin search for connected components */
791:   cum_queue = 0;
792:   ncc       = 0;
793:   for (n = 0; n < graph->n_subsets; n++) {
794:     PetscInt pid   = n + 1; /* partition labeled by 0 is discarded */
795:     PetscInt found = 0, prev = 0, first = 0, ncc_pid = 0;
796:     while (found != graph->subset_size[n]) {
797:       PetscInt added = 0;
798:       if (!prev) { /* search for new starting dof */
799:         while (PetscBTLookup(graph->touched, graph->subset_idxs[n][first])) first++;
800:         PetscCall(PetscBTSet(graph->touched, graph->subset_idxs[n][first]));
801:         graph->queue[cum_queue] = graph->subset_idxs[n][first];
802:         graph->cptr[ncc]        = cum_queue;
803:         prev                    = 1;
804:         cum_queue++;
805:         found++;
806:         ncc_pid++;
807:         ncc++;
808:       }
809:       PetscCall(PCBDDCGraphComputeCC_Private(graph, pid, graph->queue + cum_queue, prev, &added));
810:       if (!added) {
811:         graph->subset_ncc[n] = ncc_pid;
812:         graph->cptr[ncc]     = cum_queue;
813:       }
814:       prev = added;
815:       found += added;
816:       cum_queue += added;
817:       if (added && found == graph->subset_size[n]) {
818:         graph->subset_ncc[n] = ncc_pid;
819:         graph->cptr[ncc]     = cum_queue;
820:       }
821:     }
822:   }
823:   graph->ncc          = ncc;
824:   graph->queue_sorted = PETSC_FALSE;
825:   PetscFunctionReturn(PETSC_SUCCESS);
826: }

828: PetscErrorCode PCBDDCGraphSetUp(PCBDDCGraph graph, PetscInt custom_minimal_size, IS neumann_is, IS dirichlet_is, PetscInt n_ISForDofs, IS ISForDofs[], IS custom_primal_vertices)
829: {
830:   IS              subset, subset_n;
831:   MPI_Comm        comm;
832:   const PetscInt *is_indices;
833:   PetscInt        n_neigh, *neigh, *n_shared, **shared, *queue_global;
834:   PetscInt        i, j, k, s, total_counts, nodes_touched, is_size;
835:   PetscMPIInt     commsize;
836:   PetscBool       same_set, mirrors_found;

838:   PetscFunctionBegin;
840:   if (neumann_is) {
842:     PetscCheckSameComm(graph->l2gmap, 1, neumann_is, 3);
843:   }
844:   graph->has_dirichlet = PETSC_FALSE;
845:   if (dirichlet_is) {
847:     PetscCheckSameComm(graph->l2gmap, 1, dirichlet_is, 4);
848:     graph->has_dirichlet = PETSC_TRUE;
849:   }
851:   for (i = 0; i < n_ISForDofs; i++) {
853:     PetscCheckSameComm(graph->l2gmap, 1, ISForDofs[i], 6);
854:   }
855:   if (custom_primal_vertices) {
857:     PetscCheckSameComm(graph->l2gmap, 1, custom_primal_vertices, 7);
858:   }
859:   PetscCall(PetscObjectGetComm((PetscObject)(graph->l2gmap), &comm));
860:   PetscCallMPI(MPI_Comm_size(comm, &commsize));

862:   /* custom_minimal_size */
863:   graph->custom_minimal_size = custom_minimal_size;
864:   /* get info l2gmap and allocate work vectors  */
865:   PetscCall(ISLocalToGlobalMappingGetInfo(graph->l2gmap, &n_neigh, &neigh, &n_shared, &shared));
866:   /* check if we have any local periodic nodes (periodic BCs) */
867:   mirrors_found = PETSC_FALSE;
868:   if (graph->nvtxs && n_neigh) {
869:     for (i = 0; i < n_shared[0]; i++) graph->count[shared[0][i]] += 1;
870:     for (i = 0; i < n_shared[0]; i++) {
871:       if (graph->count[shared[0][i]] > 1) {
872:         mirrors_found = PETSC_TRUE;
873:         break;
874:       }
875:     }
876:   }
877:   /* compute local mirrors (if any) */
878:   if (mirrors_found) {
879:     IS        to, from;
880:     PetscInt *local_indices, *global_indices;

882:     PetscCall(ISCreateStride(PETSC_COMM_SELF, graph->nvtxs, 0, 1, &to));
883:     PetscCall(ISLocalToGlobalMappingApplyIS(graph->l2gmap, to, &from));
884:     /* get arrays of local and global indices */
885:     PetscCall(PetscMalloc1(graph->nvtxs, &local_indices));
886:     PetscCall(ISGetIndices(to, (const PetscInt **)&is_indices));
887:     PetscCall(PetscArraycpy(local_indices, is_indices, graph->nvtxs));
888:     PetscCall(ISRestoreIndices(to, (const PetscInt **)&is_indices));
889:     PetscCall(PetscMalloc1(graph->nvtxs, &global_indices));
890:     PetscCall(ISGetIndices(from, (const PetscInt **)&is_indices));
891:     PetscCall(PetscArraycpy(global_indices, is_indices, graph->nvtxs));
892:     PetscCall(ISRestoreIndices(from, (const PetscInt **)&is_indices));
893:     /* allocate space for mirrors */
894:     PetscCall(PetscMalloc2(graph->nvtxs, &graph->mirrors, graph->nvtxs, &graph->mirrors_set));
895:     PetscCall(PetscArrayzero(graph->mirrors, graph->nvtxs));
896:     graph->mirrors_set[0] = NULL;

898:     k = 0;
899:     for (i = 0; i < n_shared[0]; i++) {
900:       j = shared[0][i];
901:       if (graph->count[j] > 1) {
902:         graph->mirrors[j]++;
903:         k++;
904:       }
905:     }
906:     /* allocate space for set of mirrors */
907:     PetscCall(PetscMalloc1(k, &graph->mirrors_set[0]));
908:     for (i = 1; i < graph->nvtxs; i++) graph->mirrors_set[i] = graph->mirrors_set[i - 1] + graph->mirrors[i - 1];

910:     /* fill arrays */
911:     PetscCall(PetscArrayzero(graph->mirrors, graph->nvtxs));
912:     for (j = 0; j < n_shared[0]; j++) {
913:       i = shared[0][j];
914:       if (graph->count[i] > 1) graph->mirrors_set[i][graph->mirrors[i]++] = global_indices[i];
915:     }
916:     PetscCall(PetscSortIntWithArray(graph->nvtxs, global_indices, local_indices));
917:     for (i = 0; i < graph->nvtxs; i++) {
918:       if (graph->mirrors[i] > 0) {
919:         PetscCall(PetscFindInt(graph->mirrors_set[i][0], graph->nvtxs, global_indices, &k));
920:         j = global_indices[k];
921:         while (k > 0 && global_indices[k - 1] == j) k--;
922:         for (j = 0; j < graph->mirrors[i]; j++) graph->mirrors_set[i][j] = local_indices[k + j];
923:         PetscCall(PetscSortInt(graph->mirrors[i], graph->mirrors_set[i]));
924:       }
925:     }
926:     PetscCall(PetscFree(local_indices));
927:     PetscCall(PetscFree(global_indices));
928:     PetscCall(ISDestroy(&to));
929:     PetscCall(ISDestroy(&from));
930:   }
931:   PetscCall(PetscArrayzero(graph->count, graph->nvtxs));

933:   /* Count total number of neigh per node */
934:   k = 0;
935:   for (i = 1; i < n_neigh; i++) {
936:     k += n_shared[i];
937:     for (j = 0; j < n_shared[i]; j++) graph->count[shared[i][j]] += 1;
938:   }
939:   /* Allocate space for storing the set of neighbours for each node */
940:   if (graph->nvtxs) PetscCall(PetscMalloc1(k, &graph->neighbours_set[0]));
941:   for (i = 1; i < graph->nvtxs; i++) { /* dont count myself */
942:     graph->neighbours_set[i] = graph->neighbours_set[i - 1] + graph->count[i - 1];
943:   }
944:   /* Get information for sharing subdomains */
945:   PetscCall(PetscArrayzero(graph->count, graph->nvtxs));
946:   for (i = 1; i < n_neigh; i++) { /* dont count myself */
947:     s = n_shared[i];
948:     for (j = 0; j < s; j++) {
949:       k                                         = shared[i][j];
950:       graph->neighbours_set[k][graph->count[k]] = neigh[i];
951:       graph->count[k] += 1;
952:     }
953:   }
954:   /* sort set of sharing subdomains */
955:   for (i = 0; i < graph->nvtxs; i++) PetscCall(PetscSortRemoveDupsInt(&graph->count[i], graph->neighbours_set[i]));
956:   /* free memory allocated by ISLocalToGlobalMappingGetInfo */
957:   PetscCall(ISLocalToGlobalMappingRestoreInfo(graph->l2gmap, &n_neigh, &neigh, &n_shared, &shared));

959:   /*
960:      Get info for dofs splitting
961:      User can specify just a subset; an additional field is considered as a complementary field
962:   */
963:   for (i = 0, k = 0; i < n_ISForDofs; i++) {
964:     PetscInt bs;

966:     PetscCall(ISGetBlockSize(ISForDofs[i], &bs));
967:     k += bs;
968:   }
969:   for (i = 0; i < graph->nvtxs; i++) graph->which_dof[i] = k; /* by default a dof belongs to the complement set */
970:   for (i = 0, k = 0; i < n_ISForDofs; i++) {
971:     PetscInt bs;

973:     PetscCall(ISGetLocalSize(ISForDofs[i], &is_size));
974:     PetscCall(ISGetBlockSize(ISForDofs[i], &bs));
975:     PetscCall(ISGetIndices(ISForDofs[i], (const PetscInt **)&is_indices));
976:     for (j = 0; j < is_size / bs; j++) {
977:       PetscInt b;

979:       for (b = 0; b < bs; b++) {
980:         PetscInt jj = bs * j + b;

982:         if (is_indices[jj] > -1 && is_indices[jj] < graph->nvtxs) { /* out of bounds indices (if any) are skipped */
983:           graph->which_dof[is_indices[jj]] = k + b;
984:         }
985:       }
986:     }
987:     PetscCall(ISRestoreIndices(ISForDofs[i], (const PetscInt **)&is_indices));
988:     k += bs;
989:   }

991:   /* Take into account Neumann nodes */
992:   if (neumann_is) {
993:     PetscCall(ISGetLocalSize(neumann_is, &is_size));
994:     PetscCall(ISGetIndices(neumann_is, (const PetscInt **)&is_indices));
995:     for (i = 0; i < is_size; i++) {
996:       if (is_indices[i] > -1 && is_indices[i] < graph->nvtxs) { /* out of bounds indices (if any) are skipped */
997:         graph->special_dof[is_indices[i]] = PCBDDCGRAPH_NEUMANN_MARK;
998:       }
999:     }
1000:     PetscCall(ISRestoreIndices(neumann_is, (const PetscInt **)&is_indices));
1001:   }
1002:   /* Take into account Dirichlet nodes (they overwrite any neumann boundary mark previously set) */
1003:   if (dirichlet_is) {
1004:     PetscCall(ISGetLocalSize(dirichlet_is, &is_size));
1005:     PetscCall(ISGetIndices(dirichlet_is, (const PetscInt **)&is_indices));
1006:     for (i = 0; i < is_size; i++) {
1007:       if (is_indices[i] > -1 && is_indices[i] < graph->nvtxs) { /* out of bounds indices (if any) are skipped */
1008:         if (commsize > graph->commsizelimit) {                  /* dirichlet nodes treated as internal */
1009:           PetscCall(PetscBTSet(graph->touched, is_indices[i]));
1010:           graph->subset[is_indices[i]] = 0;
1011:         }
1012:         graph->special_dof[is_indices[i]] = PCBDDCGRAPH_DIRICHLET_MARK;
1013:       }
1014:     }
1015:     PetscCall(ISRestoreIndices(dirichlet_is, (const PetscInt **)&is_indices));
1016:   }
1017:   /* mark local periodic nodes (if any) and adapt CSR graph (if any) */
1018:   if (graph->mirrors) {
1019:     for (i = 0; i < graph->nvtxs; i++)
1020:       if (graph->mirrors[i]) graph->special_dof[i] = PCBDDCGRAPH_LOCAL_PERIODIC_MARK;

1022:     if (graph->xadj) {
1023:       PetscInt *new_xadj, *new_adjncy;
1024:       /* sort CSR graph */
1025:       for (i = 0; i < graph->nvtxs; i++) PetscCall(PetscSortInt(graph->xadj[i + 1] - graph->xadj[i], &graph->adjncy[graph->xadj[i]]));
1026:       /* adapt local CSR graph in case of local periodicity */
1027:       k = 0;
1028:       for (i = 0; i < graph->nvtxs; i++)
1029:         for (j = graph->xadj[i]; j < graph->xadj[i + 1]; j++) k += graph->mirrors[graph->adjncy[j]];

1031:       PetscCall(PetscMalloc1(graph->nvtxs + 1, &new_xadj));
1032:       PetscCall(PetscMalloc1(k + graph->xadj[graph->nvtxs], &new_adjncy));
1033:       new_xadj[0] = 0;
1034:       for (i = 0; i < graph->nvtxs; i++) {
1035:         k = graph->xadj[i + 1] - graph->xadj[i];
1036:         PetscCall(PetscArraycpy(&new_adjncy[new_xadj[i]], &graph->adjncy[graph->xadj[i]], k));
1037:         new_xadj[i + 1] = new_xadj[i] + k;
1038:         for (j = graph->xadj[i]; j < graph->xadj[i + 1]; j++) {
1039:           k = graph->mirrors[graph->adjncy[j]];
1040:           PetscCall(PetscArraycpy(&new_adjncy[new_xadj[i + 1]], graph->mirrors_set[graph->adjncy[j]], k));
1041:           new_xadj[i + 1] += k;
1042:         }
1043:         k = new_xadj[i + 1] - new_xadj[i];
1044:         PetscCall(PetscSortRemoveDupsInt(&k, &new_adjncy[new_xadj[i]]));
1045:         new_xadj[i + 1] = new_xadj[i] + k;
1046:       }
1047:       /* set new CSR into graph */
1048:       PetscCall(PetscFree(graph->xadj));
1049:       PetscCall(PetscFree(graph->adjncy));
1050:       graph->xadj   = new_xadj;
1051:       graph->adjncy = new_adjncy;
1052:     }
1053:   }

1055:   /* mark special nodes (if any) -> each will become a single node equivalence class */
1056:   if (custom_primal_vertices) {
1057:     PetscCall(ISGetLocalSize(custom_primal_vertices, &is_size));
1058:     PetscCall(ISGetIndices(custom_primal_vertices, (const PetscInt **)&is_indices));
1059:     for (i = 0, j = 0; i < is_size; i++) {
1060:       if (is_indices[i] > -1 && is_indices[i] < graph->nvtxs && graph->special_dof[is_indices[i]] != PCBDDCGRAPH_DIRICHLET_MARK) { /* out of bounds indices (if any) are skipped */
1061:         graph->special_dof[is_indices[i]] = PCBDDCGRAPH_SPECIAL_MARK - j;
1062:         j++;
1063:       }
1064:     }
1065:     PetscCall(ISRestoreIndices(custom_primal_vertices, (const PetscInt **)&is_indices));
1066:   }

1068:   /* mark interior nodes (if commsize > graph->commsizelimit) as touched and belonging to partition number 0 */
1069:   if (commsize > graph->commsizelimit) {
1070:     for (i = 0; i < graph->nvtxs; i++) {
1071:       if (!graph->count[i]) {
1072:         PetscCall(PetscBTSet(graph->touched, i));
1073:         graph->subset[i] = 0;
1074:       }
1075:     }
1076:   }

1078:   /* init graph structure and compute default subsets */
1079:   nodes_touched = 0;
1080:   for (i = 0; i < graph->nvtxs; i++) {
1081:     if (PetscBTLookup(graph->touched, i)) nodes_touched++;
1082:   }
1083:   i            = 0;
1084:   graph->ncc   = 0;
1085:   total_counts = 0;

1087:   /* allocated space for queues */
1088:   if (commsize == graph->commsizelimit) {
1089:     PetscCall(PetscMalloc2(graph->nvtxs + 1, &graph->cptr, graph->nvtxs, &graph->queue));
1090:   } else {
1091:     PetscInt nused = graph->nvtxs - nodes_touched;
1092:     PetscCall(PetscMalloc2(nused + 1, &graph->cptr, nused, &graph->queue));
1093:   }

1095:   while (nodes_touched < graph->nvtxs) {
1096:     /*  find first untouched node in local ordering */
1097:     while (PetscBTLookup(graph->touched, i)) i++;
1098:     PetscCall(PetscBTSet(graph->touched, i));
1099:     graph->subset[i]           = graph->ncc + 1;
1100:     graph->cptr[graph->ncc]    = total_counts;
1101:     graph->queue[total_counts] = i;
1102:     total_counts++;
1103:     nodes_touched++;
1104:     /* now find all other nodes having the same set of sharing subdomains */
1105:     for (j = i + 1; j < graph->nvtxs; j++) {
1106:       /* check for same number of sharing subdomains, dof number and same special mark */
1107:       if (!PetscBTLookup(graph->touched, j) && graph->count[i] == graph->count[j] && graph->which_dof[i] == graph->which_dof[j] && graph->special_dof[i] == graph->special_dof[j]) {
1108:         /* check for same set of sharing subdomains */
1109:         same_set = PETSC_TRUE;
1110:         for (k = 0; k < graph->count[j]; k++) {
1111:           if (graph->neighbours_set[i][k] != graph->neighbours_set[j][k]) same_set = PETSC_FALSE;
1112:         }
1113:         /* I have found a friend of mine */
1114:         if (same_set) {
1115:           PetscCall(PetscBTSet(graph->touched, j));
1116:           graph->subset[j] = graph->ncc + 1;
1117:           nodes_touched++;
1118:           graph->queue[total_counts] = j;
1119:           total_counts++;
1120:         }
1121:       }
1122:     }
1123:     graph->ncc++;
1124:   }
1125:   /* set default number of subsets (at this point no info on csr and/or local_subs has been taken into account, so n_subsets = ncc */
1126:   graph->n_subsets = graph->ncc;
1127:   PetscCall(PetscMalloc1(graph->n_subsets, &graph->subset_ncc));
1128:   for (i = 0; i < graph->n_subsets; i++) graph->subset_ncc[i] = 1;
1129:   /* final pointer */
1130:   graph->cptr[graph->ncc] = total_counts;

1132:   /* For consistency reasons (among neighbours), I need to sort (by global ordering) each connected component */
1133:   /* Get a reference node (min index in global ordering) for each subset for tagging messages */
1134:   PetscCall(PetscMalloc1(graph->ncc, &graph->subset_ref_node));
1135:   PetscCall(PetscMalloc1(graph->cptr[graph->ncc], &queue_global));
1136:   PetscCall(ISLocalToGlobalMappingApply(graph->l2gmap, graph->cptr[graph->ncc], graph->queue, queue_global));
1137:   for (j = 0; j < graph->ncc; j++) {
1138:     PetscCall(PetscSortIntWithArray(graph->cptr[j + 1] - graph->cptr[j], &queue_global[graph->cptr[j]], &graph->queue[graph->cptr[j]]));
1139:     graph->subset_ref_node[j] = graph->queue[graph->cptr[j]];
1140:   }
1141:   PetscCall(PetscFree(queue_global));
1142:   graph->queue_sorted = PETSC_TRUE;

1144:   /* save information on subsets (needed when analyzing the connected components) */
1145:   if (graph->ncc) {
1146:     PetscCall(PetscMalloc2(graph->ncc, &graph->subset_size, graph->ncc, &graph->subset_idxs));
1147:     PetscCall(PetscMalloc1(graph->cptr[graph->ncc], &graph->subset_idxs[0]));
1148:     PetscCall(PetscArrayzero(graph->subset_idxs[0], graph->cptr[graph->ncc]));
1149:     for (j = 1; j < graph->ncc; j++) {
1150:       graph->subset_size[j - 1] = graph->cptr[j] - graph->cptr[j - 1];
1151:       graph->subset_idxs[j]     = graph->subset_idxs[j - 1] + graph->subset_size[j - 1];
1152:     }
1153:     graph->subset_size[graph->ncc - 1] = graph->cptr[graph->ncc] - graph->cptr[graph->ncc - 1];
1154:     PetscCall(PetscArraycpy(graph->subset_idxs[0], graph->queue, graph->cptr[graph->ncc]));
1155:   }

1157:   /* renumber reference nodes */
1158:   PetscCall(ISCreateGeneral(PetscObjectComm((PetscObject)(graph->l2gmap)), graph->ncc, graph->subset_ref_node, PETSC_COPY_VALUES, &subset_n));
1159:   PetscCall(ISLocalToGlobalMappingApplyIS(graph->l2gmap, subset_n, &subset));
1160:   PetscCall(ISDestroy(&subset_n));
1161:   PetscCall(ISRenumber(subset, NULL, NULL, &subset_n));
1162:   PetscCall(ISDestroy(&subset));
1163:   PetscCall(ISGetLocalSize(subset_n, &k));
1164:   PetscCheck(k == graph->ncc, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Invalid size of new subset! %" PetscInt_FMT " != %" PetscInt_FMT, k, graph->ncc);
1165:   PetscCall(ISGetIndices(subset_n, &is_indices));
1166:   PetscCall(PetscArraycpy(graph->subset_ref_node, is_indices, graph->ncc));
1167:   PetscCall(ISRestoreIndices(subset_n, &is_indices));
1168:   PetscCall(ISDestroy(&subset_n));

1170:   /* free workspace */
1171:   graph->setupcalled = PETSC_TRUE;
1172:   PetscFunctionReturn(PETSC_SUCCESS);
1173: }

1175: PetscErrorCode PCBDDCGraphResetCoords(PCBDDCGraph graph)
1176: {
1177:   PetscFunctionBegin;
1178:   if (!graph) PetscFunctionReturn(PETSC_SUCCESS);
1179:   PetscCall(PetscFree(graph->coords));
1180:   graph->cdim  = 0;
1181:   graph->cnloc = 0;
1182:   graph->cloc  = PETSC_FALSE;
1183:   PetscFunctionReturn(PETSC_SUCCESS);
1184: }

1186: PetscErrorCode PCBDDCGraphResetCSR(PCBDDCGraph graph)
1187: {
1188:   PetscFunctionBegin;
1189:   if (!graph) PetscFunctionReturn(PETSC_SUCCESS);
1190:   if (graph->freecsr) {
1191:     PetscCall(PetscFree(graph->xadj));
1192:     PetscCall(PetscFree(graph->adjncy));
1193:   } else {
1194:     graph->xadj   = NULL;
1195:     graph->adjncy = NULL;
1196:   }
1197:   graph->freecsr   = PETSC_FALSE;
1198:   graph->nvtxs_csr = 0;
1199:   PetscFunctionReturn(PETSC_SUCCESS);
1200: }

1202: PetscErrorCode PCBDDCGraphReset(PCBDDCGraph graph)
1203: {
1204:   PetscFunctionBegin;
1205:   if (!graph) PetscFunctionReturn(PETSC_SUCCESS);
1206:   PetscCall(ISLocalToGlobalMappingDestroy(&graph->l2gmap));
1207:   PetscCall(PetscFree(graph->subset_ncc));
1208:   PetscCall(PetscFree(graph->subset_ref_node));
1209:   if (graph->nvtxs) PetscCall(PetscFree(graph->neighbours_set[0]));
1210:   PetscCall(PetscBTDestroy(&graph->touched));
1211:   PetscCall(PetscFree5(graph->count, graph->neighbours_set, graph->subset, graph->which_dof, graph->special_dof));
1212:   PetscCall(PetscFree2(graph->cptr, graph->queue));
1213:   if (graph->mirrors) PetscCall(PetscFree(graph->mirrors_set[0]));
1214:   PetscCall(PetscFree2(graph->mirrors, graph->mirrors_set));
1215:   if (graph->subset_idxs) PetscCall(PetscFree(graph->subset_idxs[0]));
1216:   PetscCall(PetscFree2(graph->subset_size, graph->subset_idxs));
1217:   PetscCall(ISDestroy(&graph->dirdofs));
1218:   PetscCall(ISDestroy(&graph->dirdofsB));
1219:   if (graph->n_local_subs) PetscCall(PetscFree(graph->local_subs));
1220:   graph->has_dirichlet       = PETSC_FALSE;
1221:   graph->twodimset           = PETSC_FALSE;
1222:   graph->twodim              = PETSC_FALSE;
1223:   graph->nvtxs               = 0;
1224:   graph->nvtxs_global        = 0;
1225:   graph->n_subsets           = 0;
1226:   graph->custom_minimal_size = 1;
1227:   graph->n_local_subs        = 0;
1228:   graph->maxcount            = PETSC_MAX_INT;
1229:   graph->setupcalled         = PETSC_FALSE;
1230:   PetscFunctionReturn(PETSC_SUCCESS);
1231: }

1233: PetscErrorCode PCBDDCGraphInit(PCBDDCGraph graph, ISLocalToGlobalMapping l2gmap, PetscInt N, PetscInt maxcount)
1234: {
1235:   PetscInt n;

1237:   PetscFunctionBegin;
1242:   /* raise an error if already allocated */
1243:   PetscCheck(!graph->nvtxs_global, PetscObjectComm((PetscObject)l2gmap), PETSC_ERR_PLIB, "BDDCGraph already initialized");
1244:   /* set number of vertices */
1245:   PetscCall(PetscObjectReference((PetscObject)l2gmap));
1246:   graph->l2gmap = l2gmap;
1247:   PetscCall(ISLocalToGlobalMappingGetSize(l2gmap, &n));
1248:   graph->nvtxs        = n;
1249:   graph->nvtxs_global = N;
1250:   /* allocate used space */
1251:   PetscCall(PetscBTCreate(graph->nvtxs, &graph->touched));
1252:   PetscCall(PetscMalloc5(graph->nvtxs, &graph->count, graph->nvtxs, &graph->neighbours_set, graph->nvtxs, &graph->subset, graph->nvtxs, &graph->which_dof, graph->nvtxs, &graph->special_dof));
1253:   /* zeroes memory */
1254:   PetscCall(PetscArrayzero(graph->count, graph->nvtxs));
1255:   PetscCall(PetscArrayzero(graph->subset, graph->nvtxs));
1256:   /* use -1 as a default value for which_dof array */
1257:   for (n = 0; n < graph->nvtxs; n++) graph->which_dof[n] = -1;
1258:   PetscCall(PetscArrayzero(graph->special_dof, graph->nvtxs));
1259:   /* zeroes first pointer to neighbour set */
1260:   if (graph->nvtxs) graph->neighbours_set[0] = NULL;
1261:   /* zeroes workspace for values of ncc */
1262:   graph->subset_ncc      = NULL;
1263:   graph->subset_ref_node = NULL;
1264:   /* maxcount for cc */
1265:   graph->maxcount = maxcount;
1266:   PetscFunctionReturn(PETSC_SUCCESS);
1267: }

1269: PetscErrorCode PCBDDCGraphDestroy(PCBDDCGraph *graph)
1270: {
1271:   PetscFunctionBegin;
1272:   PetscCall(PCBDDCGraphResetCSR(*graph));
1273:   PetscCall(PCBDDCGraphResetCoords(*graph));
1274:   PetscCall(PCBDDCGraphReset(*graph));
1275:   PetscCall(PetscFree(*graph));
1276:   PetscFunctionReturn(PETSC_SUCCESS);
1277: }

1279: PetscErrorCode PCBDDCGraphCreate(PCBDDCGraph *graph)
1280: {
1281:   PCBDDCGraph new_graph;

1283:   PetscFunctionBegin;
1284:   PetscCall(PetscNew(&new_graph));
1285:   new_graph->custom_minimal_size = 1;
1286:   new_graph->commsizelimit       = 1;
1287:   *graph                         = new_graph;
1288:   PetscFunctionReturn(PETSC_SUCCESS);
1289: }