Actual source code: telescope.c
1: #include <petsc/private/petscimpl.h>
2: #include <petsc/private/matimpl.h>
3: #include <petsc/private/pcimpl.h>
4: #include <petscksp.h>
5: #include <petscdm.h>
6: #include "../src/ksp/pc/impls/telescope/telescope.h"
8: static PetscBool cited = PETSC_FALSE;
9: static const char citation[] = "@inproceedings{MaySananRuppKnepleySmith2016,\n"
10: " title = {Extreme-Scale Multigrid Components within PETSc},\n"
11: " author = {Dave A. May and Patrick Sanan and Karl Rupp and Matthew G. Knepley and Barry F. Smith},\n"
12: " booktitle = {Proceedings of the Platform for Advanced Scientific Computing Conference},\n"
13: " series = {PASC '16},\n"
14: " isbn = {978-1-4503-4126-4},\n"
15: " location = {Lausanne, Switzerland},\n"
16: " pages = {5:1--5:12},\n"
17: " articleno = {5},\n"
18: " numpages = {12},\n"
19: " url = {https://doi.acm.org/10.1145/2929908.2929913},\n"
20: " doi = {10.1145/2929908.2929913},\n"
21: " acmid = {2929913},\n"
22: " publisher = {ACM},\n"
23: " address = {New York, NY, USA},\n"
24: " keywords = {GPU, HPC, agglomeration, coarse-level solver, multigrid, parallel computing, preconditioning},\n"
25: " year = {2016}\n"
26: "}\n";
28: /*
29: default setup mode
31: [1a] scatter to (FORWARD)
32: x(comm) -> xtmp(comm)
33: [1b] local copy (to) ranks with color = 0
34: xred(subcomm) <- xtmp
36: [2] solve on sub KSP to obtain yred(subcomm)
38: [3a] local copy (from) ranks with color = 0
39: yred(subcomm) --> xtmp
40: [2b] scatter from (REVERSE)
41: xtmp(comm) -> y(comm)
42: */
44: /*
45: Collective[comm_f]
46: Notes
47: * Using comm_f = MPI_COMM_NULL will result in an error
48: * Using comm_c = MPI_COMM_NULL is valid. If all instances of comm_c are NULL the subcomm is not valid.
49: * If any non NULL comm_c communicator cannot map any of its ranks to comm_f, the subcomm is not valid.
50: */
51: static PetscErrorCode PCTelescopeTestValidSubcomm(MPI_Comm comm_f, MPI_Comm comm_c, PetscBool *isvalid)
52: {
53: PetscInt valid = 1;
54: MPI_Group group_f, group_c;
55: PetscMPIInt count, k, size_f = 0, size_c = 0, size_c_sum = 0;
56: PetscMPIInt *ranks_f, *ranks_c;
58: PetscFunctionBegin;
59: PetscCheck(comm_f != MPI_COMM_NULL, PETSC_COMM_SELF, PETSC_ERR_SUP, "comm_f cannot be MPI_COMM_NULL");
61: PetscCallMPI(MPI_Comm_group(comm_f, &group_f));
62: if (comm_c != MPI_COMM_NULL) PetscCallMPI(MPI_Comm_group(comm_c, &group_c));
64: PetscCallMPI(MPI_Comm_size(comm_f, &size_f));
65: if (comm_c != MPI_COMM_NULL) PetscCallMPI(MPI_Comm_size(comm_c, &size_c));
67: /* check not all comm_c's are NULL */
68: size_c_sum = size_c;
69: PetscCallMPI(MPI_Allreduce(MPI_IN_PLACE, &size_c_sum, 1, MPI_INT, MPI_SUM, comm_f));
70: if (size_c_sum == 0) valid = 0;
72: /* check we can map at least 1 rank in comm_c to comm_f */
73: PetscCall(PetscMalloc1(size_f, &ranks_f));
74: PetscCall(PetscMalloc1(size_c, &ranks_c));
75: for (k = 0; k < size_f; k++) ranks_f[k] = MPI_UNDEFINED;
76: for (k = 0; k < size_c; k++) ranks_c[k] = k;
78: /*
79: MPI_Group_translate_ranks() returns a non-zero exit code if any rank cannot be translated.
80: I do not want the code to terminate immediately if this occurs, rather I want to throw
81: the error later (during PCSetUp_Telescope()) via SETERRQ() with a message indicating
82: that comm_c is not a valid sub-communicator.
83: Hence I purposefully do not call PetscCall() after MPI_Group_translate_ranks().
84: */
85: count = 0;
86: if (comm_c != MPI_COMM_NULL) {
87: (void)MPI_Group_translate_ranks(group_c, size_c, ranks_c, group_f, ranks_f);
88: for (k = 0; k < size_f; k++) {
89: if (ranks_f[k] == MPI_UNDEFINED) count++;
90: }
91: }
92: if (count == size_f) valid = 0;
94: PetscCall(MPIU_Allreduce(MPI_IN_PLACE, &valid, 1, MPIU_INT, MPI_MIN, comm_f));
95: if (valid == 1) *isvalid = PETSC_TRUE;
96: else *isvalid = PETSC_FALSE;
98: PetscCall(PetscFree(ranks_f));
99: PetscCall(PetscFree(ranks_c));
100: PetscCallMPI(MPI_Group_free(&group_f));
101: if (comm_c != MPI_COMM_NULL) PetscCallMPI(MPI_Group_free(&group_c));
102: PetscFunctionReturn(PETSC_SUCCESS);
103: }
105: static DM private_PCTelescopeGetSubDM(PC_Telescope sred)
106: {
107: DM subdm = NULL;
109: if (!PCTelescope_isActiveRank(sred)) {
110: subdm = NULL;
111: } else {
112: switch (sred->sr_type) {
113: case TELESCOPE_DEFAULT:
114: subdm = NULL;
115: break;
116: case TELESCOPE_DMDA:
117: subdm = ((PC_Telescope_DMDACtx *)sred->dm_ctx)->dmrepart;
118: break;
119: case TELESCOPE_DMPLEX:
120: subdm = NULL;
121: break;
122: case TELESCOPE_COARSEDM:
123: if (sred->ksp) PetscCallAbort(PETSC_COMM_SELF, KSPGetDM(sred->ksp, &subdm));
124: break;
125: }
126: }
127: return subdm;
128: }
130: static PetscErrorCode PCTelescopeSetUp_default(PC pc, PC_Telescope sred)
131: {
132: PetscInt m, M, bs, st, ed;
133: Vec x, xred, yred, xtmp;
134: Mat B;
135: MPI_Comm comm, subcomm;
136: VecScatter scatter;
137: IS isin;
138: VecType vectype;
140: PetscFunctionBegin;
141: PetscCall(PetscInfo(pc, "PCTelescope: setup (default)\n"));
142: comm = PetscSubcommParent(sred->psubcomm);
143: subcomm = PetscSubcommChild(sred->psubcomm);
145: PetscCall(PCGetOperators(pc, NULL, &B));
146: PetscCall(MatGetSize(B, &M, NULL));
147: PetscCall(MatGetBlockSize(B, &bs));
148: PetscCall(MatCreateVecs(B, &x, NULL));
149: PetscCall(MatGetVecType(B, &vectype));
151: xred = NULL;
152: m = 0;
153: if (PCTelescope_isActiveRank(sred)) {
154: PetscCall(VecCreate(subcomm, &xred));
155: PetscCall(VecSetSizes(xred, PETSC_DECIDE, M));
156: PetscCall(VecSetBlockSize(xred, bs));
157: PetscCall(VecSetType(xred, vectype)); /* Use the preconditioner matrix's vectype by default */
158: PetscCall(VecSetFromOptions(xred));
159: PetscCall(VecGetLocalSize(xred, &m));
160: }
162: yred = NULL;
163: if (PCTelescope_isActiveRank(sred)) PetscCall(VecDuplicate(xred, &yred));
165: PetscCall(VecCreate(comm, &xtmp));
166: PetscCall(VecSetSizes(xtmp, m, PETSC_DECIDE));
167: PetscCall(VecSetBlockSize(xtmp, bs));
168: PetscCall(VecSetType(xtmp, vectype));
170: if (PCTelescope_isActiveRank(sred)) {
171: PetscCall(VecGetOwnershipRange(xred, &st, &ed));
172: PetscCall(ISCreateStride(comm, (ed - st), st, 1, &isin));
173: } else {
174: PetscCall(VecGetOwnershipRange(x, &st, &ed));
175: PetscCall(ISCreateStride(comm, 0, st, 1, &isin));
176: }
177: PetscCall(ISSetBlockSize(isin, bs));
179: PetscCall(VecScatterCreate(x, isin, xtmp, NULL, &scatter));
181: sred->isin = isin;
182: sred->scatter = scatter;
183: sred->xred = xred;
184: sred->yred = yred;
185: sred->xtmp = xtmp;
186: PetscCall(VecDestroy(&x));
187: PetscFunctionReturn(PETSC_SUCCESS);
188: }
190: static PetscErrorCode PCTelescopeMatCreate_default(PC pc, PC_Telescope sred, MatReuse reuse, Mat *A)
191: {
192: MPI_Comm comm, subcomm;
193: Mat Bred, B;
194: PetscInt nr, nc, bs;
195: IS isrow, iscol;
196: Mat Blocal, *_Blocal;
198: PetscFunctionBegin;
199: PetscCall(PetscInfo(pc, "PCTelescope: updating the redundant preconditioned operator (default)\n"));
200: PetscCall(PetscObjectGetComm((PetscObject)pc, &comm));
201: subcomm = PetscSubcommChild(sred->psubcomm);
202: PetscCall(PCGetOperators(pc, NULL, &B));
203: PetscCall(MatGetSize(B, &nr, &nc));
204: isrow = sred->isin;
205: PetscCall(ISCreateStride(PETSC_COMM_SELF, nc, 0, 1, &iscol));
206: PetscCall(ISSetIdentity(iscol));
207: PetscCall(MatGetBlockSizes(B, NULL, &bs));
208: PetscCall(ISSetBlockSize(iscol, bs));
209: PetscCall(MatSetOption(B, MAT_SUBMAT_SINGLEIS, PETSC_TRUE));
210: PetscCall(MatCreateSubMatrices(B, 1, &isrow, &iscol, MAT_INITIAL_MATRIX, &_Blocal));
211: Blocal = *_Blocal;
212: PetscCall(PetscFree(_Blocal));
213: Bred = NULL;
214: if (PCTelescope_isActiveRank(sred)) {
215: PetscInt mm;
217: if (reuse != MAT_INITIAL_MATRIX) Bred = *A;
219: PetscCall(MatGetSize(Blocal, &mm, NULL));
220: PetscCall(MatCreateMPIMatConcatenateSeqMat(subcomm, Blocal, mm, reuse, &Bred));
221: }
222: *A = Bred;
223: PetscCall(ISDestroy(&iscol));
224: PetscCall(MatDestroy(&Blocal));
225: PetscFunctionReturn(PETSC_SUCCESS);
226: }
228: static PetscErrorCode PCTelescopeSubNullSpaceCreate_Telescope(PC pc, PC_Telescope sred, MatNullSpace nullspace, MatNullSpace *sub_nullspace)
229: {
230: PetscBool has_const;
231: const Vec *vecs;
232: Vec *sub_vecs = NULL;
233: PetscInt i, k, n = 0;
234: MPI_Comm subcomm;
236: PetscFunctionBegin;
237: subcomm = PetscSubcommChild(sred->psubcomm);
238: PetscCall(MatNullSpaceGetVecs(nullspace, &has_const, &n, &vecs));
240: if (PCTelescope_isActiveRank(sred)) {
241: if (n) PetscCall(VecDuplicateVecs(sred->xred, n, &sub_vecs));
242: }
244: /* copy entries */
245: for (k = 0; k < n; k++) {
246: const PetscScalar *x_array;
247: PetscScalar *LA_sub_vec;
248: PetscInt st, ed;
250: /* pull in vector x->xtmp */
251: PetscCall(VecScatterBegin(sred->scatter, vecs[k], sred->xtmp, INSERT_VALUES, SCATTER_FORWARD));
252: PetscCall(VecScatterEnd(sred->scatter, vecs[k], sred->xtmp, INSERT_VALUES, SCATTER_FORWARD));
253: if (sub_vecs) {
254: /* copy vector entries into xred */
255: PetscCall(VecGetArrayRead(sred->xtmp, &x_array));
256: if (sub_vecs[k]) {
257: PetscCall(VecGetOwnershipRange(sub_vecs[k], &st, &ed));
258: PetscCall(VecGetArray(sub_vecs[k], &LA_sub_vec));
259: for (i = 0; i < ed - st; i++) LA_sub_vec[i] = x_array[i];
260: PetscCall(VecRestoreArray(sub_vecs[k], &LA_sub_vec));
261: }
262: PetscCall(VecRestoreArrayRead(sred->xtmp, &x_array));
263: }
264: }
266: if (PCTelescope_isActiveRank(sred)) {
267: /* create new (near) nullspace for redundant object */
268: PetscCall(MatNullSpaceCreate(subcomm, has_const, n, sub_vecs, sub_nullspace));
269: PetscCall(VecDestroyVecs(n, &sub_vecs));
270: PetscCheck(!nullspace->remove, PetscObjectComm((PetscObject)pc), PETSC_ERR_SUP, "Propagation of custom remove callbacks not supported when propagating (near) nullspaces with PCTelescope");
271: PetscCheck(!nullspace->rmctx, PetscObjectComm((PetscObject)pc), PETSC_ERR_SUP, "Propagation of custom remove callback context not supported when propagating (near) nullspaces with PCTelescope");
272: }
273: PetscFunctionReturn(PETSC_SUCCESS);
274: }
276: static PetscErrorCode PCTelescopeMatNullSpaceCreate_default(PC pc, PC_Telescope sred, Mat sub_mat)
277: {
278: Mat B;
280: PetscFunctionBegin;
281: PetscCall(PCGetOperators(pc, NULL, &B));
282: /* Propagate the nullspace if it exists */
283: {
284: MatNullSpace nullspace, sub_nullspace;
285: PetscCall(MatGetNullSpace(B, &nullspace));
286: if (nullspace) {
287: PetscCall(PetscInfo(pc, "PCTelescope: generating nullspace (default)\n"));
288: PetscCall(PCTelescopeSubNullSpaceCreate_Telescope(pc, sred, nullspace, &sub_nullspace));
289: if (PCTelescope_isActiveRank(sred)) {
290: PetscCall(MatSetNullSpace(sub_mat, sub_nullspace));
291: PetscCall(MatNullSpaceDestroy(&sub_nullspace));
292: }
293: }
294: }
295: /* Propagate the near nullspace if it exists */
296: {
297: MatNullSpace nearnullspace, sub_nearnullspace;
298: PetscCall(MatGetNearNullSpace(B, &nearnullspace));
299: if (nearnullspace) {
300: PetscCall(PetscInfo(pc, "PCTelescope: generating near nullspace (default)\n"));
301: PetscCall(PCTelescopeSubNullSpaceCreate_Telescope(pc, sred, nearnullspace, &sub_nearnullspace));
302: if (PCTelescope_isActiveRank(sred)) {
303: PetscCall(MatSetNearNullSpace(sub_mat, sub_nearnullspace));
304: PetscCall(MatNullSpaceDestroy(&sub_nearnullspace));
305: }
306: }
307: }
308: PetscFunctionReturn(PETSC_SUCCESS);
309: }
311: static PetscErrorCode PCView_Telescope(PC pc, PetscViewer viewer)
312: {
313: PC_Telescope sred = (PC_Telescope)pc->data;
314: PetscBool iascii, isstring;
315: PetscViewer subviewer;
317: PetscFunctionBegin;
318: PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERASCII, &iascii));
319: PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERSTRING, &isstring));
320: if (iascii) {
321: {
322: MPI_Comm comm, subcomm;
323: PetscMPIInt comm_size, subcomm_size;
324: DM dm = NULL, subdm = NULL;
326: PetscCall(PCGetDM(pc, &dm));
327: subdm = private_PCTelescopeGetSubDM(sred);
329: if (sred->psubcomm) {
330: comm = PetscSubcommParent(sred->psubcomm);
331: subcomm = PetscSubcommChild(sred->psubcomm);
332: PetscCallMPI(MPI_Comm_size(comm, &comm_size));
333: PetscCallMPI(MPI_Comm_size(subcomm, &subcomm_size));
335: PetscCall(PetscViewerASCIIPushTab(viewer));
336: PetscCall(PetscViewerASCIIPrintf(viewer, "petsc subcomm: parent comm size reduction factor = %" PetscInt_FMT "\n", sred->redfactor));
337: PetscCall(PetscViewerASCIIPrintf(viewer, "petsc subcomm: parent_size = %d , subcomm_size = %d\n", (int)comm_size, (int)subcomm_size));
338: switch (sred->subcommtype) {
339: case PETSC_SUBCOMM_INTERLACED:
340: PetscCall(PetscViewerASCIIPrintf(viewer, "petsc subcomm: type = %s\n", PetscSubcommTypes[sred->subcommtype]));
341: break;
342: case PETSC_SUBCOMM_CONTIGUOUS:
343: PetscCall(PetscViewerASCIIPrintf(viewer, "petsc subcomm type = %s\n", PetscSubcommTypes[sred->subcommtype]));
344: break;
345: default:
346: SETERRQ(PetscObjectComm((PetscObject)pc), PETSC_ERR_SUP, "General subcomm type not supported by PCTelescope");
347: }
348: PetscCall(PetscViewerASCIIPopTab(viewer));
349: } else {
350: PetscCall(PetscObjectGetComm((PetscObject)pc, &comm));
351: subcomm = sred->subcomm;
352: if (!PCTelescope_isActiveRank(sred)) subcomm = PETSC_COMM_SELF;
354: PetscCall(PetscViewerASCIIPushTab(viewer));
355: PetscCall(PetscViewerASCIIPrintf(viewer, "subcomm: using user provided sub-communicator\n"));
356: PetscCall(PetscViewerASCIIPopTab(viewer));
357: }
359: PetscCall(PetscViewerGetSubViewer(viewer, subcomm, &subviewer));
360: if (PCTelescope_isActiveRank(sred)) {
361: PetscCall(PetscViewerASCIIPushTab(subviewer));
363: if (dm && sred->ignore_dm) PetscCall(PetscViewerASCIIPrintf(subviewer, "ignoring DM\n"));
364: if (sred->ignore_kspcomputeoperators) PetscCall(PetscViewerASCIIPrintf(subviewer, "ignoring KSPComputeOperators\n"));
365: switch (sred->sr_type) {
366: case TELESCOPE_DEFAULT:
367: PetscCall(PetscViewerASCIIPrintf(subviewer, "setup type: default\n"));
368: break;
369: case TELESCOPE_DMDA:
370: PetscCall(PetscViewerASCIIPrintf(subviewer, "setup type: DMDA auto-repartitioning\n"));
371: PetscCall(DMView_DA_Short(subdm, subviewer));
372: break;
373: case TELESCOPE_DMPLEX:
374: PetscCall(PetscViewerASCIIPrintf(subviewer, "setup type: DMPLEX auto-repartitioning\n"));
375: break;
376: case TELESCOPE_COARSEDM:
377: PetscCall(PetscViewerASCIIPrintf(subviewer, "setup type: coarse DM\n"));
378: break;
379: }
381: if (dm) {
382: PetscObject obj = (PetscObject)dm;
383: PetscCall(PetscViewerASCIIPrintf(subviewer, "Parent DM object:"));
384: PetscCall(PetscViewerASCIIUseTabs(subviewer, PETSC_FALSE));
385: if (obj->type_name) PetscCall(PetscViewerASCIIPrintf(subviewer, " type = %s;", obj->type_name));
386: if (obj->name) PetscCall(PetscViewerASCIIPrintf(subviewer, " name = %s;", obj->name));
387: if (obj->prefix) PetscCall(PetscViewerASCIIPrintf(subviewer, " prefix = %s", obj->prefix));
388: PetscCall(PetscViewerASCIIPrintf(subviewer, "\n"));
389: PetscCall(PetscViewerASCIIUseTabs(subviewer, PETSC_TRUE));
390: } else {
391: PetscCall(PetscViewerASCIIPrintf(subviewer, "Parent DM object: NULL\n"));
392: }
393: if (subdm) {
394: PetscObject obj = (PetscObject)subdm;
395: PetscCall(PetscViewerASCIIPrintf(subviewer, "Sub DM object:"));
396: PetscCall(PetscViewerASCIIUseTabs(subviewer, PETSC_FALSE));
397: if (obj->type_name) PetscCall(PetscViewerASCIIPrintf(subviewer, " type = %s;", obj->type_name));
398: if (obj->name) PetscCall(PetscViewerASCIIPrintf(subviewer, " name = %s;", obj->name));
399: if (obj->prefix) PetscCall(PetscViewerASCIIPrintf(subviewer, " prefix = %s", obj->prefix));
400: PetscCall(PetscViewerASCIIPrintf(subviewer, "\n"));
401: PetscCall(PetscViewerASCIIUseTabs(subviewer, PETSC_TRUE));
402: } else {
403: PetscCall(PetscViewerASCIIPrintf(subviewer, "Sub DM object: NULL\n"));
404: }
406: PetscCall(KSPView(sred->ksp, subviewer));
407: PetscCall(PetscViewerASCIIPopTab(subviewer));
408: }
409: PetscCall(PetscViewerRestoreSubViewer(viewer, subcomm, &subviewer));
410: }
411: }
412: PetscFunctionReturn(PETSC_SUCCESS);
413: }
415: static PetscErrorCode PCSetUp_Telescope(PC pc)
416: {
417: PC_Telescope sred = (PC_Telescope)pc->data;
418: MPI_Comm comm, subcomm = 0;
419: PCTelescopeType sr_type;
421: PetscFunctionBegin;
422: PetscCall(PetscObjectGetComm((PetscObject)pc, &comm));
424: /* Determine type of setup/update */
425: if (!pc->setupcalled) {
426: PetscBool has_dm, same;
427: DM dm;
429: sr_type = TELESCOPE_DEFAULT;
430: has_dm = PETSC_FALSE;
431: PetscCall(PCGetDM(pc, &dm));
432: if (dm) has_dm = PETSC_TRUE;
433: if (has_dm) {
434: /* check for dmda */
435: PetscCall(PetscObjectTypeCompare((PetscObject)dm, DMDA, &same));
436: if (same) {
437: PetscCall(PetscInfo(pc, "PCTelescope: found DMDA\n"));
438: sr_type = TELESCOPE_DMDA;
439: }
440: /* check for dmplex */
441: PetscCall(PetscObjectTypeCompare((PetscObject)dm, DMPLEX, &same));
442: if (same) {
443: PetscCall(PetscInfo(pc, "PCTelescope: found DMPLEX\n"));
444: sr_type = TELESCOPE_DMPLEX;
445: }
447: if (sred->use_coarse_dm) {
448: PetscCall(PetscInfo(pc, "PCTelescope: using coarse DM\n"));
449: sr_type = TELESCOPE_COARSEDM;
450: }
452: if (sred->ignore_dm) {
453: PetscCall(PetscInfo(pc, "PCTelescope: ignoring DM\n"));
454: sr_type = TELESCOPE_DEFAULT;
455: }
456: }
457: sred->sr_type = sr_type;
458: } else {
459: sr_type = sred->sr_type;
460: }
462: /* set function pointers for repartition setup, matrix creation/update, matrix (near) nullspace, and reset functionality */
463: switch (sr_type) {
464: case TELESCOPE_DEFAULT:
465: sred->pctelescope_setup_type = PCTelescopeSetUp_default;
466: sred->pctelescope_matcreate_type = PCTelescopeMatCreate_default;
467: sred->pctelescope_matnullspacecreate_type = PCTelescopeMatNullSpaceCreate_default;
468: sred->pctelescope_reset_type = NULL;
469: break;
470: case TELESCOPE_DMDA:
471: pc->ops->apply = PCApply_Telescope_dmda;
472: pc->ops->applyrichardson = PCApplyRichardson_Telescope_dmda;
473: sred->pctelescope_setup_type = PCTelescopeSetUp_dmda;
474: sred->pctelescope_matcreate_type = PCTelescopeMatCreate_dmda;
475: sred->pctelescope_matnullspacecreate_type = PCTelescopeMatNullSpaceCreate_dmda;
476: sred->pctelescope_reset_type = PCReset_Telescope_dmda;
477: break;
478: case TELESCOPE_DMPLEX:
479: SETERRQ(comm, PETSC_ERR_SUP, "Support for DMPLEX is currently not available");
480: case TELESCOPE_COARSEDM:
481: pc->ops->apply = PCApply_Telescope_CoarseDM;
482: pc->ops->applyrichardson = PCApplyRichardson_Telescope_CoarseDM;
483: sred->pctelescope_setup_type = PCTelescopeSetUp_CoarseDM;
484: sred->pctelescope_matcreate_type = NULL;
485: sred->pctelescope_matnullspacecreate_type = NULL; /* PCTelescopeMatNullSpaceCreate_CoarseDM; */
486: sred->pctelescope_reset_type = PCReset_Telescope_CoarseDM;
487: break;
488: default:
489: SETERRQ(comm, PETSC_ERR_SUP, "Support only provided for: repartitioning an operator; repartitioning a DMDA; or using a coarse DM");
490: }
492: /* subcomm definition */
493: if (!pc->setupcalled) {
494: if ((sr_type == TELESCOPE_DEFAULT) || (sr_type == TELESCOPE_DMDA)) {
495: if (!sred->psubcomm) {
496: PetscCall(PetscSubcommCreate(comm, &sred->psubcomm));
497: PetscCall(PetscSubcommSetNumber(sred->psubcomm, sred->redfactor));
498: PetscCall(PetscSubcommSetType(sred->psubcomm, sred->subcommtype));
499: sred->subcomm = PetscSubcommChild(sred->psubcomm);
500: }
501: } else { /* query PC for DM, check communicators */
502: DM dm, dm_coarse_partition = NULL;
503: MPI_Comm comm_fine, comm_coarse_partition = MPI_COMM_NULL;
504: PetscMPIInt csize_fine = 0, csize_coarse_partition = 0, cs[2], csg[2], cnt = 0;
505: PetscBool isvalidsubcomm = PETSC_TRUE;
507: PetscCall(PCGetDM(pc, &dm));
508: comm_fine = PetscObjectComm((PetscObject)dm);
509: PetscCall(DMGetCoarseDM(dm, &dm_coarse_partition));
510: if (dm_coarse_partition) cnt = 1;
511: PetscCallMPI(MPI_Allreduce(MPI_IN_PLACE, &cnt, 1, MPI_INT, MPI_SUM, comm_fine));
512: PetscCheck(cnt != 0, comm_fine, PETSC_ERR_SUP, "Zero instances of a coarse DM were found");
514: PetscCallMPI(MPI_Comm_size(comm_fine, &csize_fine));
515: if (dm_coarse_partition) {
516: comm_coarse_partition = PetscObjectComm((PetscObject)dm_coarse_partition);
517: PetscCallMPI(MPI_Comm_size(comm_coarse_partition, &csize_coarse_partition));
518: }
520: cs[0] = csize_fine;
521: cs[1] = csize_coarse_partition;
522: PetscCallMPI(MPI_Allreduce(cs, csg, 2, MPI_INT, MPI_MAX, comm_fine));
523: PetscCheck(csg[0] != csg[1], comm_fine, PETSC_ERR_SUP, "Coarse DM uses the same size communicator as the parent DM attached to the PC");
525: PetscCall(PCTelescopeTestValidSubcomm(comm_fine, comm_coarse_partition, &isvalidsubcomm));
526: PetscCheck(isvalidsubcomm, comm_fine, PETSC_ERR_SUP, "Coarse DM communicator is not a sub-communicator of parentDM->comm");
527: sred->subcomm = comm_coarse_partition;
528: }
529: }
530: subcomm = sred->subcomm;
532: /* internal KSP */
533: if (!pc->setupcalled) {
534: const char *prefix;
536: if (PCTelescope_isActiveRank(sred)) {
537: PetscCall(KSPCreate(subcomm, &sred->ksp));
538: PetscCall(KSPSetNestLevel(sred->ksp, pc->kspnestlevel));
539: PetscCall(KSPSetErrorIfNotConverged(sred->ksp, pc->erroriffailure));
540: PetscCall(PetscObjectIncrementTabLevel((PetscObject)sred->ksp, (PetscObject)pc, 1));
541: PetscCall(KSPSetType(sred->ksp, KSPPREONLY));
542: PetscCall(PCGetOptionsPrefix(pc, &prefix));
543: PetscCall(KSPSetOptionsPrefix(sred->ksp, prefix));
544: PetscCall(KSPAppendOptionsPrefix(sred->ksp, "telescope_"));
545: }
546: }
548: /* setup */
549: if (!pc->setupcalled && sred->pctelescope_setup_type) PetscCall(sred->pctelescope_setup_type(pc, sred));
550: /* update */
551: if (!pc->setupcalled) {
552: if (sred->pctelescope_matcreate_type) PetscCall(sred->pctelescope_matcreate_type(pc, sred, MAT_INITIAL_MATRIX, &sred->Bred));
553: if (sred->pctelescope_matnullspacecreate_type) PetscCall(sred->pctelescope_matnullspacecreate_type(pc, sred, sred->Bred));
554: } else {
555: if (sred->pctelescope_matcreate_type) PetscCall(sred->pctelescope_matcreate_type(pc, sred, MAT_REUSE_MATRIX, &sred->Bred));
556: }
558: /* common - no construction */
559: if (PCTelescope_isActiveRank(sred)) {
560: PetscCall(KSPSetOperators(sred->ksp, sred->Bred, sred->Bred));
561: if (pc->setfromoptionscalled && !pc->setupcalled) PetscCall(KSPSetFromOptions(sred->ksp));
562: }
563: PetscFunctionReturn(PETSC_SUCCESS);
564: }
566: static PetscErrorCode PCApply_Telescope(PC pc, Vec x, Vec y)
567: {
568: PC_Telescope sred = (PC_Telescope)pc->data;
569: Vec xtmp, xred, yred;
570: PetscInt i, st, ed;
571: VecScatter scatter;
572: PetscScalar *array;
573: const PetscScalar *x_array;
575: PetscFunctionBegin;
576: PetscCall(PetscCitationsRegister(citation, &cited));
578: xtmp = sred->xtmp;
579: scatter = sred->scatter;
580: xred = sred->xred;
581: yred = sred->yred;
583: /* pull in vector x->xtmp */
584: PetscCall(VecScatterBegin(scatter, x, xtmp, INSERT_VALUES, SCATTER_FORWARD));
585: PetscCall(VecScatterEnd(scatter, x, xtmp, INSERT_VALUES, SCATTER_FORWARD));
587: /* copy vector entries into xred */
588: PetscCall(VecGetArrayRead(xtmp, &x_array));
589: if (xred) {
590: PetscScalar *LA_xred;
591: PetscCall(VecGetOwnershipRange(xred, &st, &ed));
592: PetscCall(VecGetArray(xred, &LA_xred));
593: for (i = 0; i < ed - st; i++) LA_xred[i] = x_array[i];
594: PetscCall(VecRestoreArray(xred, &LA_xred));
595: }
596: PetscCall(VecRestoreArrayRead(xtmp, &x_array));
597: /* solve */
598: if (PCTelescope_isActiveRank(sred)) {
599: PetscCall(KSPSolve(sred->ksp, xred, yred));
600: PetscCall(KSPCheckSolve(sred->ksp, pc, yred));
601: }
602: /* return vector */
603: PetscCall(VecGetArray(xtmp, &array));
604: if (yred) {
605: const PetscScalar *LA_yred;
606: PetscCall(VecGetOwnershipRange(yred, &st, &ed));
607: PetscCall(VecGetArrayRead(yred, &LA_yred));
608: for (i = 0; i < ed - st; i++) array[i] = LA_yred[i];
609: PetscCall(VecRestoreArrayRead(yred, &LA_yred));
610: }
611: PetscCall(VecRestoreArray(xtmp, &array));
612: PetscCall(VecScatterBegin(scatter, xtmp, y, INSERT_VALUES, SCATTER_REVERSE));
613: PetscCall(VecScatterEnd(scatter, xtmp, y, INSERT_VALUES, SCATTER_REVERSE));
614: PetscFunctionReturn(PETSC_SUCCESS);
615: }
617: static PetscErrorCode PCApplyRichardson_Telescope(PC pc, Vec x, Vec y, Vec w, PetscReal rtol, PetscReal abstol, PetscReal dtol, PetscInt its, PetscBool zeroguess, PetscInt *outits, PCRichardsonConvergedReason *reason)
618: {
619: PC_Telescope sred = (PC_Telescope)pc->data;
620: Vec xtmp, yred;
621: PetscInt i, st, ed;
622: VecScatter scatter;
623: const PetscScalar *x_array;
624: PetscBool default_init_guess_value;
626: PetscFunctionBegin;
627: xtmp = sred->xtmp;
628: scatter = sred->scatter;
629: yred = sred->yred;
631: PetscCheck(its <= 1, PetscObjectComm((PetscObject)pc), PETSC_ERR_SUP, "PCApplyRichardson_Telescope only supports max_it = 1");
632: *reason = (PCRichardsonConvergedReason)0;
634: if (!zeroguess) {
635: PetscCall(PetscInfo(pc, "PCTelescope: Scattering y for non-zero initial guess\n"));
636: /* pull in vector y->xtmp */
637: PetscCall(VecScatterBegin(scatter, y, xtmp, INSERT_VALUES, SCATTER_FORWARD));
638: PetscCall(VecScatterEnd(scatter, y, xtmp, INSERT_VALUES, SCATTER_FORWARD));
640: /* copy vector entries into xred */
641: PetscCall(VecGetArrayRead(xtmp, &x_array));
642: if (yred) {
643: PetscScalar *LA_yred;
644: PetscCall(VecGetOwnershipRange(yred, &st, &ed));
645: PetscCall(VecGetArray(yred, &LA_yred));
646: for (i = 0; i < ed - st; i++) LA_yred[i] = x_array[i];
647: PetscCall(VecRestoreArray(yred, &LA_yred));
648: }
649: PetscCall(VecRestoreArrayRead(xtmp, &x_array));
650: }
652: if (PCTelescope_isActiveRank(sred)) {
653: PetscCall(KSPGetInitialGuessNonzero(sred->ksp, &default_init_guess_value));
654: if (!zeroguess) PetscCall(KSPSetInitialGuessNonzero(sred->ksp, PETSC_TRUE));
655: }
657: PetscCall(PCApply_Telescope(pc, x, y));
659: if (PCTelescope_isActiveRank(sred)) PetscCall(KSPSetInitialGuessNonzero(sred->ksp, default_init_guess_value));
661: if (!*reason) *reason = PCRICHARDSON_CONVERGED_ITS;
662: *outits = 1;
663: PetscFunctionReturn(PETSC_SUCCESS);
664: }
666: static PetscErrorCode PCReset_Telescope(PC pc)
667: {
668: PC_Telescope sred = (PC_Telescope)pc->data;
670: PetscFunctionBegin;
671: PetscCall(ISDestroy(&sred->isin));
672: PetscCall(VecScatterDestroy(&sred->scatter));
673: PetscCall(VecDestroy(&sred->xred));
674: PetscCall(VecDestroy(&sred->yred));
675: PetscCall(VecDestroy(&sred->xtmp));
676: PetscCall(MatDestroy(&sred->Bred));
677: PetscCall(KSPReset(sred->ksp));
678: if (sred->pctelescope_reset_type) PetscCall(sred->pctelescope_reset_type(pc));
679: PetscFunctionReturn(PETSC_SUCCESS);
680: }
682: static PetscErrorCode PCDestroy_Telescope(PC pc)
683: {
684: PC_Telescope sred = (PC_Telescope)pc->data;
686: PetscFunctionBegin;
687: PetscCall(PCReset_Telescope(pc));
688: PetscCall(KSPDestroy(&sred->ksp));
689: PetscCall(PetscSubcommDestroy(&sred->psubcomm));
690: PetscCall(PetscFree(sred->dm_ctx));
691: PetscCall(PetscObjectComposeFunction((PetscObject)pc, "PCTelescopeGetKSP_C", NULL));
692: PetscCall(PetscObjectComposeFunction((PetscObject)pc, "PCTelescopeGetSubcommType_C", NULL));
693: PetscCall(PetscObjectComposeFunction((PetscObject)pc, "PCTelescopeSetSubcommType_C", NULL));
694: PetscCall(PetscObjectComposeFunction((PetscObject)pc, "PCTelescopeGetReductionFactor_C", NULL));
695: PetscCall(PetscObjectComposeFunction((PetscObject)pc, "PCTelescopeSetReductionFactor_C", NULL));
696: PetscCall(PetscObjectComposeFunction((PetscObject)pc, "PCTelescopeGetIgnoreDM_C", NULL));
697: PetscCall(PetscObjectComposeFunction((PetscObject)pc, "PCTelescopeSetIgnoreDM_C", NULL));
698: PetscCall(PetscObjectComposeFunction((PetscObject)pc, "PCTelescopeGetIgnoreKSPComputeOperators_C", NULL));
699: PetscCall(PetscObjectComposeFunction((PetscObject)pc, "PCTelescopeSetIgnoreKSPComputeOperators_C", NULL));
700: PetscCall(PetscObjectComposeFunction((PetscObject)pc, "PCTelescopeGetDM_C", NULL));
701: PetscCall(PetscObjectComposeFunction((PetscObject)pc, "PCTelescopeGetUseCoarseDM_C", NULL));
702: PetscCall(PetscObjectComposeFunction((PetscObject)pc, "PCTelescopeSetUseCoarseDM_C", NULL));
703: PetscCall(PetscFree(pc->data));
704: PetscFunctionReturn(PETSC_SUCCESS);
705: }
707: static PetscErrorCode PCSetFromOptions_Telescope(PC pc, PetscOptionItems *PetscOptionsObject)
708: {
709: PC_Telescope sred = (PC_Telescope)pc->data;
710: MPI_Comm comm;
711: PetscMPIInt size;
712: PetscBool flg;
713: PetscSubcommType subcommtype;
715: PetscFunctionBegin;
716: PetscCall(PetscObjectGetComm((PetscObject)pc, &comm));
717: PetscCallMPI(MPI_Comm_size(comm, &size));
718: PetscOptionsHeadBegin(PetscOptionsObject, "Telescope options");
719: PetscCall(PetscOptionsEnum("-pc_telescope_subcomm_type", "Subcomm type (interlaced or contiguous)", "PCTelescopeSetSubcommType", PetscSubcommTypes, (PetscEnum)sred->subcommtype, (PetscEnum *)&subcommtype, &flg));
720: if (flg) PetscCall(PCTelescopeSetSubcommType(pc, subcommtype));
721: PetscCall(PetscOptionsInt("-pc_telescope_reduction_factor", "Factor to reduce comm size by", "PCTelescopeSetReductionFactor", sred->redfactor, &sred->redfactor, NULL));
722: PetscCheck(sred->redfactor <= size, comm, PETSC_ERR_ARG_WRONG, "-pc_telescope_reduction_factor <= comm size");
723: PetscCall(PetscOptionsBool("-pc_telescope_ignore_dm", "Ignore any DM attached to the PC", "PCTelescopeSetIgnoreDM", sred->ignore_dm, &sred->ignore_dm, NULL));
724: PetscCall(PetscOptionsBool("-pc_telescope_ignore_kspcomputeoperators", "Ignore method used to compute A", "PCTelescopeSetIgnoreKSPComputeOperators", sred->ignore_kspcomputeoperators, &sred->ignore_kspcomputeoperators, NULL));
725: PetscCall(PetscOptionsBool("-pc_telescope_use_coarse_dm", "Define sub-communicator from the coarse DM", "PCTelescopeSetUseCoarseDM", sred->use_coarse_dm, &sred->use_coarse_dm, NULL));
726: PetscOptionsHeadEnd();
727: PetscFunctionReturn(PETSC_SUCCESS);
728: }
730: /* PC simplementation specific API's */
732: static PetscErrorCode PCTelescopeGetKSP_Telescope(PC pc, KSP *ksp)
733: {
734: PC_Telescope red = (PC_Telescope)pc->data;
735: PetscFunctionBegin;
736: if (ksp) *ksp = red->ksp;
737: PetscFunctionReturn(PETSC_SUCCESS);
738: }
740: static PetscErrorCode PCTelescopeGetSubcommType_Telescope(PC pc, PetscSubcommType *subcommtype)
741: {
742: PC_Telescope red = (PC_Telescope)pc->data;
743: PetscFunctionBegin;
744: if (subcommtype) *subcommtype = red->subcommtype;
745: PetscFunctionReturn(PETSC_SUCCESS);
746: }
748: static PetscErrorCode PCTelescopeSetSubcommType_Telescope(PC pc, PetscSubcommType subcommtype)
749: {
750: PC_Telescope red = (PC_Telescope)pc->data;
752: PetscFunctionBegin;
753: PetscCheck(!pc->setupcalled, PetscObjectComm((PetscObject)pc), PETSC_ERR_ARG_WRONGSTATE, "You cannot change the subcommunicator type for PCTelescope after it has been set up.");
754: red->subcommtype = subcommtype;
755: PetscFunctionReturn(PETSC_SUCCESS);
756: }
758: static PetscErrorCode PCTelescopeGetReductionFactor_Telescope(PC pc, PetscInt *fact)
759: {
760: PC_Telescope red = (PC_Telescope)pc->data;
761: PetscFunctionBegin;
762: if (fact) *fact = red->redfactor;
763: PetscFunctionReturn(PETSC_SUCCESS);
764: }
766: static PetscErrorCode PCTelescopeSetReductionFactor_Telescope(PC pc, PetscInt fact)
767: {
768: PC_Telescope red = (PC_Telescope)pc->data;
769: PetscMPIInt size;
771: PetscFunctionBegin;
772: PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)pc), &size));
773: PetscCheck(fact > 0, PetscObjectComm((PetscObject)pc), PETSC_ERR_ARG_WRONG, "Reduction factor of telescoping PC %" PetscInt_FMT " must be positive", fact);
774: PetscCheck(fact <= size, PetscObjectComm((PetscObject)pc), PETSC_ERR_ARG_WRONG, "Reduction factor of telescoping PC %" PetscInt_FMT " must be <= comm.size", fact);
775: red->redfactor = fact;
776: PetscFunctionReturn(PETSC_SUCCESS);
777: }
779: static PetscErrorCode PCTelescopeGetIgnoreDM_Telescope(PC pc, PetscBool *v)
780: {
781: PC_Telescope red = (PC_Telescope)pc->data;
782: PetscFunctionBegin;
783: if (v) *v = red->ignore_dm;
784: PetscFunctionReturn(PETSC_SUCCESS);
785: }
787: static PetscErrorCode PCTelescopeSetIgnoreDM_Telescope(PC pc, PetscBool v)
788: {
789: PC_Telescope red = (PC_Telescope)pc->data;
790: PetscFunctionBegin;
791: red->ignore_dm = v;
792: PetscFunctionReturn(PETSC_SUCCESS);
793: }
795: static PetscErrorCode PCTelescopeGetUseCoarseDM_Telescope(PC pc, PetscBool *v)
796: {
797: PC_Telescope red = (PC_Telescope)pc->data;
798: PetscFunctionBegin;
799: if (v) *v = red->use_coarse_dm;
800: PetscFunctionReturn(PETSC_SUCCESS);
801: }
803: static PetscErrorCode PCTelescopeSetUseCoarseDM_Telescope(PC pc, PetscBool v)
804: {
805: PC_Telescope red = (PC_Telescope)pc->data;
806: PetscFunctionBegin;
807: red->use_coarse_dm = v;
808: PetscFunctionReturn(PETSC_SUCCESS);
809: }
811: static PetscErrorCode PCTelescopeGetIgnoreKSPComputeOperators_Telescope(PC pc, PetscBool *v)
812: {
813: PC_Telescope red = (PC_Telescope)pc->data;
814: PetscFunctionBegin;
815: if (v) *v = red->ignore_kspcomputeoperators;
816: PetscFunctionReturn(PETSC_SUCCESS);
817: }
819: static PetscErrorCode PCTelescopeSetIgnoreKSPComputeOperators_Telescope(PC pc, PetscBool v)
820: {
821: PC_Telescope red = (PC_Telescope)pc->data;
822: PetscFunctionBegin;
823: red->ignore_kspcomputeoperators = v;
824: PetscFunctionReturn(PETSC_SUCCESS);
825: }
827: static PetscErrorCode PCTelescopeGetDM_Telescope(PC pc, DM *dm)
828: {
829: PC_Telescope red = (PC_Telescope)pc->data;
830: PetscFunctionBegin;
831: *dm = private_PCTelescopeGetSubDM(red);
832: PetscFunctionReturn(PETSC_SUCCESS);
833: }
835: /*@
836: PCTelescopeGetKSP - Gets the `KSP` created by the telescoping `PC`.
838: Not Collective
840: Input Parameter:
841: . pc - the preconditioner context
843: Output Parameter:
844: . subksp - the `KSP` defined on the smaller set of processes
846: Level: advanced
848: .seealso: [](ch_ksp), `PC`, `KSP`, `PCTELESCOPE`
849: @*/
850: PetscErrorCode PCTelescopeGetKSP(PC pc, KSP *subksp)
851: {
852: PetscFunctionBegin;
853: PetscUseMethod(pc, "PCTelescopeGetKSP_C", (PC, KSP *), (pc, subksp));
854: PetscFunctionReturn(PETSC_SUCCESS);
855: }
857: /*@
858: PCTelescopeGetReductionFactor - Gets the factor by which the original number of MPI processes has been reduced by that was set by
859: `PCTelescopeSetReductionFactor()`
861: Not Collective
863: Input Parameter:
864: . pc - the preconditioner context
866: Output Parameter:
867: . fact - the reduction factor
869: Level: advanced
871: .seealso: [](ch_ksp), `PC`, `PCTELESCOPE`, `PCTelescopeSetReductionFactor()`
872: @*/
873: PetscErrorCode PCTelescopeGetReductionFactor(PC pc, PetscInt *fact)
874: {
875: PetscFunctionBegin;
876: PetscUseMethod(pc, "PCTelescopeGetReductionFactor_C", (PC, PetscInt *), (pc, fact));
877: PetscFunctionReturn(PETSC_SUCCESS);
878: }
880: /*@
881: PCTelescopeSetReductionFactor - Sets the factor by which the original number of MPI processes will been reduced by.
883: Not Collective
885: Input Parameter:
886: . pc - the preconditioner context
888: Output Parameter:
889: . fact - the reduction factor
891: Level: advanced
893: .seealso: [](ch_ksp), `PCTELESCOPE`, `PCTelescopeGetReductionFactor()`
894: @*/
895: PetscErrorCode PCTelescopeSetReductionFactor(PC pc, PetscInt fact)
896: {
897: PetscFunctionBegin;
898: PetscTryMethod(pc, "PCTelescopeSetReductionFactor_C", (PC, PetscInt), (pc, fact));
899: PetscFunctionReturn(PETSC_SUCCESS);
900: }
902: /*@
903: PCTelescopeGetIgnoreDM - Get the flag indicating if any `DM` attached to the `PC` will be used in constructing the `PC` on the
904: reduced number of MPI processes
906: Not Collective
908: Input Parameter:
909: . pc - the preconditioner context
911: Output Parameter:
912: . v - the flag
914: Level: advanced
916: .seealso: [](ch_ksp), `DM`, `PCTELESCOPE`, `PCTelescopeSetIgnoreDM()`
917: @*/
918: PetscErrorCode PCTelescopeGetIgnoreDM(PC pc, PetscBool *v)
919: {
920: PetscFunctionBegin;
921: PetscUseMethod(pc, "PCTelescopeGetIgnoreDM_C", (PC, PetscBool *), (pc, v));
922: PetscFunctionReturn(PETSC_SUCCESS);
923: }
925: /*@
926: PCTelescopeSetIgnoreDM - Set a flag to ignore any `DM` attached to the `PC` when constructing the `PC` on the
927: reduced number of MPI processes
929: Not Collective
931: Input Parameter:
932: . pc - the preconditioner context
934: Output Parameter:
935: . v - Use `PETSC_TRUE` to ignore any `DM`
937: Level: advanced
939: .seealso: [](ch_ksp), `DM`, `PCTELESCOPE`, `PCTelescopeGetIgnoreDM()`
940: @*/
941: PetscErrorCode PCTelescopeSetIgnoreDM(PC pc, PetscBool v)
942: {
943: PetscFunctionBegin;
944: PetscTryMethod(pc, "PCTelescopeSetIgnoreDM_C", (PC, PetscBool), (pc, v));
945: PetscFunctionReturn(PETSC_SUCCESS);
946: }
948: /*@
949: PCTelescopeGetUseCoarseDM - Get the flag indicating if the coarse `DM` attached to `DM` associated with the `PC` will be used in constructing
950: the `PC` on the reduced number of MPI processes
952: Not Collective
954: Input Parameter:
955: . pc - the preconditioner context
957: Output Parameter:
958: . v - the flag
960: Level: advanced
962: .seealso: [](ch_ksp), `DM`, `PCTELESCOPE`, `PCTelescopeSetIgnoreDM()`, `PCTelescopeSetUseCoarseDM()`
963: @*/
964: PetscErrorCode PCTelescopeGetUseCoarseDM(PC pc, PetscBool *v)
965: {
966: PetscFunctionBegin;
967: PetscUseMethod(pc, "PCTelescopeGetUseCoarseDM_C", (PC, PetscBool *), (pc, v));
968: PetscFunctionReturn(PETSC_SUCCESS);
969: }
971: /*@
972: PCTelescopeSetUseCoarseDM - Set a flag to query the `DM` attached to the `PC` if it also has a coarse `DM` and utilize that `DM`
973: in constructing the `PC` on the reduced number of MPI processes
975: Not Collective
977: Input Parameter:
978: . pc - the preconditioner context
980: Output Parameter:
981: . v - Use `PETSC_FALSE` to ignore any coarse `DM`
983: Level: advanced
985: Notes:
986: When you have specified to use a coarse `DM`, the communicator used to create the sub-`KSP` within `PCTELESCOPE`
987: will be that of the coarse `DM`. Hence the flags `-pc_telescope_reduction_factor` and
988: `-pc_telescope_subcomm_type` will no longer have any meaning.
990: It is required that the communicator associated with the parent (fine) and the coarse `DM` are of different sizes.
991: An error will occur of the size of the communicator associated with the coarse `DM`
992: is the same as that of the parent `DM`.
993: Furthermore, it is required that the communicator on the coarse `DM` is a sub-communicator of the parent.
994: This will be checked at the time the preconditioner is setup and an error will occur if
995: the coarse `DM` does not define a sub-communicator of that used by the parent `DM`.
997: The particular Telescope setup invoked when using a coarse `DM` is agnostic with respect to the type of
998: the `DM` used (e.g. it supports `DMSHELL`, `DMPLEX`, etc).
1000: Support is currently only provided for the case when you are using `KSPSetComputeOperators()`
1002: The user is required to compose a function with the parent `DM` to facilitate the transfer of fields (`Vec`)
1003: between the different decompositions defined by the fine and coarse `DM`s.
1004: In the user code, this is achieved via
1005: .vb
1006: {
1007: DM dm_fine;
1008: PetscObjectCompose((PetscObject)dm_fine,"PCTelescopeFieldScatter",your_field_scatter_method);
1009: }
1010: .ve
1011: The signature of the user provided field scatter method is
1012: .vb
1013: PetscErrorCode your_field_scatter_method(DM dm_fine,Vec x_fine,ScatterMode mode,DM dm_coarse,Vec x_coarse);
1014: .ve
1015: The user must provide support for both mode `SCATTER_FORWARD` and mode `SCATTER_REVERSE`.
1016: `SCATTER_FORWARD` implies the direction of transfer is from the parent (fine) `DM` to the coarse `DM`.
1018: Optionally, the user may also compose a function with the parent `DM` to facilitate the transfer
1019: of state variables between the fine and coarse `DM`s.
1020: In the context of a finite element discretization, an example state variable might be
1021: values associated with quadrature points within each element.
1022: A user provided state scatter method is composed via
1023: .vb
1024: {
1025: DM dm_fine;
1026: PetscObjectCompose((PetscObject)dm_fine,"PCTelescopeStateScatter",your_state_scatter_method);
1027: }
1028: .ve
1029: The signature of the user provided state scatter method is
1030: .vb
1031: PetscErrorCode your_state_scatter_method(DM dm_fine,ScatterMode mode,DM dm_coarse);
1032: .ve
1033: `SCATTER_FORWARD` implies the direction of transfer is from the fine `DM` to the coarse `DM`.
1034: The user is only required to support mode = `SCATTER_FORWARD`.
1035: No assumption is made about the data type of the state variables.
1036: These must be managed by the user and must be accessible from the `DM`.
1038: Care must be taken in defining the user context passed to `KSPSetComputeOperators()` which is to be
1039: associated with the sub-`KSP` residing within `PCTELESCOPE`.
1040: In general, `PCTELESCOPE` assumes that the context on the fine and coarse `DM` used with
1041: `KSPSetComputeOperators()` should be "similar" in type or origin.
1042: Specifically the following rules are used to infer what context on the sub-`KSP` should be.
1044: First the contexts from the `KSP` and the fine and coarse `DM`s are retrieved.
1045: Note that the special case of a `DMSHELL` context is queried.
1047: .vb
1048: DMKSPGetComputeOperators(dm_fine,&dmfine_kspfunc,&dmfine_kspctx);
1049: DMGetApplicationContext(dm_fine,&dmfine_appctx);
1050: DMShellGetContext(dm_fine,&dmfine_shellctx);
1052: DMGetApplicationContext(dm_coarse,&dmcoarse_appctx);
1053: DMShellGetContext(dm_coarse,&dmcoarse_shellctx);
1054: .ve
1056: The following rules are then enforced\:
1058: 1. If `dmfine_kspctx` = `NULL`, then we provide a `NULL` pointer as the context for the sub-`KSP`\:
1059: `KSPSetComputeOperators`(`sub_ksp`,`dmfine_kspfunc`,`NULL`);
1061: 2. If `dmfine_kspctx` != `NULL` and `dmfine_kspctx` == `dmfine_appctx`,
1063: check that `dmcoarse_appctx` is also non-`NULL`. If this is true, then\:
1064: `KSPSetComputeOperators`(`sub_ksp`,`dmfine_kspfunc`,`dmcoarse_appctx`);
1066: 3. If `dmfine_kspctx` != `NULL` and `dmfine_kspctx` == `dmfine_shellctx`,
1068: check that `dmcoarse_shellctx` is also non-`NULL`. If this is true, then\:
1069: `KSPSetComputeOperators`(`sub_ksp`,`dmfine_kspfunc`,`dmcoarse_shellctx`);
1071: If neither of the above three tests passed, then `PCTELESCOPE` cannot safely determine what
1072: context should be provided to `KSPSetComputeOperators()` for use with the sub-`KSP`.
1073: In this case, an additional mechanism is provided via a composed function which will return
1074: the actual context to be used. To use this feature you must compose the "getter" function
1075: with the coarse `DM`, e.g.
1076: .vb
1077: {
1078: DM dm_coarse;
1079: PetscObjectCompose((PetscObject)dm_coarse,"PCTelescopeGetCoarseDMKSPContext",your_coarse_context_getter);
1080: }
1081: .ve
1082: The signature of the user provided method is
1083: .vb
1084: PetscErrorCode your_coarse_context_getter(DM dm_coarse,void **your_kspcontext);
1085: .ve
1087: .seealso: [](ch_ksp), `DM`, `PCTELESCOPE`, `PCTelescopeSetIgnoreDM()`
1088: @*/
1089: PetscErrorCode PCTelescopeSetUseCoarseDM(PC pc, PetscBool v)
1090: {
1091: PetscFunctionBegin;
1092: PetscTryMethod(pc, "PCTelescopeSetUseCoarseDM_C", (PC, PetscBool), (pc, v));
1093: PetscFunctionReturn(PETSC_SUCCESS);
1094: }
1096: /*@
1097: PCTelescopeGetIgnoreKSPComputeOperators - Get the flag indicating if `KSPComputeOperators()` will be used to construct
1098: the matrix on the reduced number of MPI processes
1100: Not Collective
1102: Input Parameter:
1103: . pc - the preconditioner context
1105: Output Parameter:
1106: . v - the flag
1108: Level: advanced
1110: .seealso: [](ch_ksp), `PCTELESCOPE`, `PCTelescopeSetIgnoreDM()`, `PCTelescopeSetUseCoarseDM()`, `PCTelescopeSetIgnoreKSPComputeOperators()`
1111: @*/
1112: PetscErrorCode PCTelescopeGetIgnoreKSPComputeOperators(PC pc, PetscBool *v)
1113: {
1114: PetscFunctionBegin;
1115: PetscUseMethod(pc, "PCTelescopeGetIgnoreKSPComputeOperators_C", (PC, PetscBool *), (pc, v));
1116: PetscFunctionReturn(PETSC_SUCCESS);
1117: }
1119: /*@
1120: PCTelescopeSetIgnoreKSPComputeOperators - Set a flag to have `PCTELESCOPE` ignore the function provided to `KSPComputeOperators()` in
1121: constructint the matrix on the reduced number of MPI processes
1123: Not Collective
1125: Input Parameter:
1126: . pc - the preconditioner context
1128: Output Parameter:
1129: . v - Use `PETSC_TRUE` to ignore the function (if defined) set via `KSPSetComputeOperators()` on `pc`
1131: Level: advanced
1133: .seealso: [](ch_ksp), `PCTELESCOPE`, `PCTelescopeSetIgnoreDM()`, `PCTelescopeSetUseCoarseDM()`, `PCTelescopeGetIgnoreKSPComputeOperators()`
1134: @*/
1135: PetscErrorCode PCTelescopeSetIgnoreKSPComputeOperators(PC pc, PetscBool v)
1136: {
1137: PetscFunctionBegin;
1138: PetscTryMethod(pc, "PCTelescopeSetIgnoreKSPComputeOperators_C", (PC, PetscBool), (pc, v));
1139: PetscFunctionReturn(PETSC_SUCCESS);
1140: }
1142: /*@
1143: PCTelescopeGetDM - Get the re-partitioned `DM` attached to the sub-`KSP`.
1145: Not Collective
1147: Input Parameter:
1148: . pc - the preconditioner context
1150: Output Parameter:
1151: . subdm - The re-partitioned `DM`
1153: Level: advanced
1155: .seealso: [](ch_ksp), `DM`, `PCTELESCOPE`, `PCTelescopeSetIgnoreDM()`, `PCTelescopeSetUseCoarseDM()`, `PCTelescopeGetIgnoreKSPComputeOperators()`
1156: @*/
1157: PetscErrorCode PCTelescopeGetDM(PC pc, DM *subdm)
1158: {
1159: PetscFunctionBegin;
1160: PetscUseMethod(pc, "PCTelescopeGetDM_C", (PC, DM *), (pc, subdm));
1161: PetscFunctionReturn(PETSC_SUCCESS);
1162: }
1164: /*@
1165: PCTelescopeSetSubcommType - set subcommunicator type (interlaced or contiguous)
1167: Logically Collective
1169: Input Parameters:
1170: + pc - the preconditioner context
1171: - subcommtype - the subcommunicator type (see `PetscSubcommType`)
1173: Level: advanced
1175: .seealso: [](ch_ksp), `PetscSubcommType`, `PetscSubcomm`, `PCTELESCOPE`, `PCTelescopeGetSubcommType()`
1176: @*/
1177: PetscErrorCode PCTelescopeSetSubcommType(PC pc, PetscSubcommType subcommtype)
1178: {
1179: PetscFunctionBegin;
1180: PetscTryMethod(pc, "PCTelescopeSetSubcommType_C", (PC, PetscSubcommType), (pc, subcommtype));
1181: PetscFunctionReturn(PETSC_SUCCESS);
1182: }
1184: /*@
1185: PCTelescopeGetSubcommType - Get the subcommunicator type (interlaced or contiguous) set with `PCTelescopeSetSubcommType()`
1187: Not Collective
1189: Input Parameter:
1190: . pc - the preconditioner context
1192: Output Parameter:
1193: . subcommtype - the subcommunicator type (see `PetscSubcommType`)
1195: Level: advanced
1197: .seealso: [](ch_ksp), `PetscSubcomm`, `PetscSubcommType`, `PCTELESCOPE`, `PCTelescopeSetSubcommType()`
1198: @*/
1199: PetscErrorCode PCTelescopeGetSubcommType(PC pc, PetscSubcommType *subcommtype)
1200: {
1201: PetscFunctionBegin;
1202: PetscUseMethod(pc, "PCTelescopeGetSubcommType_C", (PC, PetscSubcommType *), (pc, subcommtype));
1203: PetscFunctionReturn(PETSC_SUCCESS);
1204: }
1206: /*MC
1207: PCTELESCOPE - Runs a `KSP` solver on a sub-communicator {cite}`maysananruppknepleysmith2016`. MPI processes not in the sub-communicator are idle during the solve.
1209: Options Database Keys:
1210: + -pc_telescope_reduction_factor <r> - factor to reduce the communicator size by. e.g. with 64 MPI ranks and r=4, the new sub-communicator will have 64/4 = 16 ranks.
1211: . -pc_telescope_ignore_dm - flag to indicate whether an attached `DM` should be ignored in constructing the new `PC`
1212: . -pc_telescope_subcomm_type <interlaced,contiguous> - defines the selection of MPI processes on the sub-communicator. see `PetscSubcomm` for more information.
1213: . -pc_telescope_ignore_kspcomputeoperators - flag to indicate whether `KSPSetComputeOperators()` should be used on the sub-`KSP`.
1214: - -pc_telescope_use_coarse_dm - flag to indicate whether the coarse `DM` should be used to define the sub-communicator.
1216: Level: advanced
1218: Notes:
1219: Assuming that the parent preconditioner `PC` is defined on a communicator c, this implementation
1220: creates a child sub-communicator (c') containing fewer MPI processes than the original parent preconditioner `PC`.
1221: The preconditioner is deemed telescopic as it only calls `KSPSolve()` on a single
1222: sub-communicator, in contrast with `PCREDUNDANT` which calls `KSPSolve()` on N sub-communicators.
1223: This means there will be MPI processes which will be idle during the application of this preconditioner.
1224: Additionally, in comparison with `PCREDUNDANT`, `PCTELESCOPE` can utilize an attached `DM` to construct `DM` dependent preconditioner, such as `PCMG`
1226: The default type of the sub `KSP` (the `KSP` defined on c') is `KSPPREONLY`.
1228: There are three setup mechanisms for `PCTELESCOPE`. Features support by each type are described below.
1229: In the following, we will refer to the operators B and B', these are the Bmat provided to the `KSP` on the
1230: communicators c and c' respectively.
1232: [1] Default setup
1233: The sub-communicator c' is created via `PetscSubcommCreate()`.
1234: Explicitly defined nullspace and near nullspace vectors will be propagated from B to B'.
1235: Currently there is no support define nullspaces via a user supplied method (e.g. as passed to `MatNullSpaceSetFunction()`).
1236: No support is provided for `KSPSetComputeOperators()`.
1237: Currently there is no support for the flag `-pc_use_amat`.
1239: [2] `DM` aware setup
1240: If a `DM` is attached to the `PC`, it is re-partitioned on the sub-communicator c'.
1241: c' is created via `PetscSubcommCreate()`.
1242: Both the Bmat operator and the right hand side vector are permuted into the new DOF ordering defined by the re-partitioned `DM`.
1243: Currently only support for re-partitioning a `DMDA` is provided.
1244: Any explicitly defined nullspace or near nullspace vectors attached to the original Bmat operator (B) are extracted, re-partitioned and set on the re-partitioned Bmat operator (B').
1245: Currently there is no support define nullspaces via a user supplied method (e.g. as passed to `MatNullSpaceSetFunction()`).
1246: Support is provided for `KSPSetComputeOperators()`. The user provided function and context is propagated to the sub `KSP`.
1247: This is fragile since the user must ensure that their user context is valid for use on c'.
1248: Currently there is no support for the flag `-pc_use_amat`.
1250: [3] Coarse `DM` setup
1251: If a `DM` (dmfine) is attached to the `PC`, dmfine is queried for a "coarse" `DM` (call this dmcoarse) via `DMGetCoarseDM()`.
1252: `PCTELESCOPE` will interpret the coarse `DM` as being defined on a sub-communicator of c.
1253: The communicator associated with dmcoarse will define the c' to be used within `PCTELESCOPE`.
1254: `PCTELESCOPE` will check that c' is in fact a sub-communicator of c. If it is not, an error will be reported.
1255: The intention of this setup type is that `PCTELESCOPE` will use an existing (e.g. user defined) communicator hierarchy, say as would be
1256: available with using multi-grid on unstructured meshes.
1257: This setup will not use the command line options `-pc_telescope_reduction_factor` or `-pc_telescope_subcomm_type`.
1258: Any explicitly defined nullspace or near nullspace vectors attached to the original Bmat operator (B) are extracted, scattered into the correct ordering consistent with dmcoarse and set on B'.
1259: Currently there is no support define nullspaces via a user supplied method (e.g. as passed to `MatNullSpaceSetFunction()`).
1260: There is no general method to permute field orderings, hence only `KSPSetComputeOperators()` is supported.
1261: The user must use `PetscObjectComposeFunction()` with dmfine to define the method to scatter fields from dmfine to dmcoarse.
1262: Propagation of the user context for `KSPSetComputeOperators()` on the sub `KSP` is attempted by querying the `DM` contexts associated with dmfine and dmcoarse. Alternatively, the user may use `PetscObjectComposeFunction()` with dmcoarse to define a method which will return the appropriate user context for `KSPSetComputeOperators()`.
1263: Currently there is no support for the flag `-pc_use_amat`.
1264: This setup can be invoked by the option `-pc_telescope_use_coarse_dm` or by calling `PCTelescopeSetUseCoarseDM`(pc,`PETSC_TRUE`);
1265: Further information about the user-provided methods required by this setup type are described here `PCTelescopeSetUseCoarseDM()`.
1267: Developer Notes:
1268: During `PCSetup()`, the B operator is scattered onto c'.
1269: Within `PCApply()`, the RHS vector (x) is scattered into a redundant vector, xred (defined on c').
1270: Then, `KSPSolve()` is executed on the c' communicator.
1272: The communicator used within the telescoping preconditioner is defined by a `PetscSubcomm` using the INTERLACED
1273: creation routine by default (this can be changed with `-pc_telescope_subcomm_type`). We run the sub `KSP` on only
1274: the ranks within the communicator which have a color equal to zero.
1276: The telescoping preconditioner is aware of nullspaces and near nullspaces which are attached to the B operator.
1277: In the case where B has a (near) nullspace attached, the (near) nullspace vectors are extracted from B and mapped into
1278: a new (near) nullspace, defined on the sub-communicator, which is attached to B' (the B operator which was scattered to c')
1280: The telescoping preconditioner can re-partition an attached `DM` if it is a `DMDA` (2D or 3D -
1281: support for 1D `DMDA`s is not provided). If a `DMDA` is found, a topologically equivalent `DMDA` is created on c'
1282: and this new `DM` is attached the sub `KSP`. The design of telescope is such that it should be possible to extend support
1283: for re-partitioning other to `DM`'s (e.g. `DMPLEX`). The user can supply a flag to ignore attached DMs.
1284: Alternatively, user-provided re-partitioned `DM`s can be used via `-pc_telescope_use_coarse_dm`.
1286: With the default setup mode, B' is defined by fusing rows (in order) associated with MPI processes common to c and c'.
1288: When a `DMDA` is attached to the parent preconditioner, B' is defined by: (i) performing a symmetric permutation of B
1289: into the ordering defined by the `DMDA` on c', (ii) extracting the local chunks via `MatCreateSubMatrices()`, (iii) fusing the
1290: locally (sequential) matrices defined on the ranks common to c and c' into B' using `MatCreateMPIMatConcatenateSeqMat()`
1292: Limitations/improvements include the following.
1293: `VecPlaceArray()` could be used within `PCApply()` to improve efficiency and reduce memory usage.
1294: A unified mechanism to query for user contexts as required by `KSPSetComputeOperators()` and `MatNullSpaceSetFunction()`.
1296: The symmetric permutation used when a `DMDA` is encountered is performed via explicitly assembling a permutation matrix P,
1297: and performing P^T.A.P. Possibly it might be more efficient to use `MatPermute()`. We opted to use P^T.A.P as it appears
1298: `VecPermute()` does not support the use case required here. By computing P, one can permute both the operator and RHS in a
1299: consistent manner.
1301: Mapping of vectors (default setup mode) is performed in the following way.
1302: Suppose the parent communicator size was 4, and we set a reduction factor of 2; this would give a comm size on c' of 2.
1303: Using the interlaced creation routine, the ranks in c with color = 0 will be rank 0 and 2.
1304: We perform the scatter to the sub-communicator in the following way.
1305: [1] Given a vector x defined on communicator c
1307: .vb
1308: rank(c) local values of x
1309: ------- ----------------------------------------
1310: 0 [ 0.0, 1.0, 2.0, 3.0, 4.0, 5.0 ]
1311: 1 [ 6.0, 7.0, 8.0, 9.0, 10.0, 11.0 ]
1312: 2 [ 12.0, 13.0, 14.0, 15.0, 16.0, 17.0 ]
1313: 3 [ 18.0, 19.0, 20.0, 21.0, 22.0, 23.0 ]
1314: .ve
1316: scatter into xtmp defined also on comm c, so that we have the following values
1318: .vb
1319: rank(c) local values of xtmp
1320: ------- ----------------------------------------------------------------------------
1321: 0 [ 0.0, 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0, 9.0, 10.0, 11.0 ]
1322: 1 [ ]
1323: 2 [ 12.0, 13.0, 14.0, 15.0, 16.0, 17.0, 18.0, 19.0, 20.0, 21.0, 22.0, 23.0 ]
1324: 3 [ ]
1325: .ve
1327: The entries on rank 1 and 3 (ranks which do not have a color = 0 in c') have no values
1329: [2] Copy the values from ranks 0, 2 (indices with respect to comm c) into the vector xred which is defined on communicator c'.
1330: Ranks 0 and 2 are the only ranks in the subcomm which have a color = 0.
1332: .vb
1333: rank(c') local values of xred
1334: -------- ----------------------------------------------------------------------------
1335: 0 [ 0.0, 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0, 9.0, 10.0, 11.0 ]
1336: 1 [ 12.0, 13.0, 14.0, 15.0, 16.0, 17.0, 18.0, 19.0, 20.0, 21.0, 22.0, 23.0 ]
1337: .ve
1339: Contributed by:
1340: Dave May
1342: .seealso: [](ch_ksp), `PCTelescopeGetKSP()`, `PCTelescopeGetDM()`, `PCTelescopeGetReductionFactor()`, `PCTelescopeSetReductionFactor()`, `PCTelescopeGetIgnoreDM()`, `PCTelescopeSetIgnoreDM()`, `PCREDUNDANT`
1343: M*/
1344: PETSC_EXTERN PetscErrorCode PCCreate_Telescope(PC pc)
1345: {
1346: struct _PC_Telescope *sred;
1348: PetscFunctionBegin;
1349: PetscCall(PetscNew(&sred));
1350: sred->psubcomm = NULL;
1351: sred->subcommtype = PETSC_SUBCOMM_INTERLACED;
1352: sred->subcomm = MPI_COMM_NULL;
1353: sred->redfactor = 1;
1354: sred->ignore_dm = PETSC_FALSE;
1355: sred->ignore_kspcomputeoperators = PETSC_FALSE;
1356: sred->use_coarse_dm = PETSC_FALSE;
1357: pc->data = (void *)sred;
1359: pc->ops->apply = PCApply_Telescope;
1360: pc->ops->applytranspose = NULL;
1361: pc->ops->applyrichardson = PCApplyRichardson_Telescope;
1362: pc->ops->setup = PCSetUp_Telescope;
1363: pc->ops->destroy = PCDestroy_Telescope;
1364: pc->ops->reset = PCReset_Telescope;
1365: pc->ops->setfromoptions = PCSetFromOptions_Telescope;
1366: pc->ops->view = PCView_Telescope;
1368: sred->pctelescope_setup_type = PCTelescopeSetUp_default;
1369: sred->pctelescope_matcreate_type = PCTelescopeMatCreate_default;
1370: sred->pctelescope_matnullspacecreate_type = PCTelescopeMatNullSpaceCreate_default;
1371: sred->pctelescope_reset_type = NULL;
1373: PetscCall(PetscObjectComposeFunction((PetscObject)pc, "PCTelescopeGetKSP_C", PCTelescopeGetKSP_Telescope));
1374: PetscCall(PetscObjectComposeFunction((PetscObject)pc, "PCTelescopeGetSubcommType_C", PCTelescopeGetSubcommType_Telescope));
1375: PetscCall(PetscObjectComposeFunction((PetscObject)pc, "PCTelescopeSetSubcommType_C", PCTelescopeSetSubcommType_Telescope));
1376: PetscCall(PetscObjectComposeFunction((PetscObject)pc, "PCTelescopeGetReductionFactor_C", PCTelescopeGetReductionFactor_Telescope));
1377: PetscCall(PetscObjectComposeFunction((PetscObject)pc, "PCTelescopeSetReductionFactor_C", PCTelescopeSetReductionFactor_Telescope));
1378: PetscCall(PetscObjectComposeFunction((PetscObject)pc, "PCTelescopeGetIgnoreDM_C", PCTelescopeGetIgnoreDM_Telescope));
1379: PetscCall(PetscObjectComposeFunction((PetscObject)pc, "PCTelescopeSetIgnoreDM_C", PCTelescopeSetIgnoreDM_Telescope));
1380: PetscCall(PetscObjectComposeFunction((PetscObject)pc, "PCTelescopeGetIgnoreKSPComputeOperators_C", PCTelescopeGetIgnoreKSPComputeOperators_Telescope));
1381: PetscCall(PetscObjectComposeFunction((PetscObject)pc, "PCTelescopeSetIgnoreKSPComputeOperators_C", PCTelescopeSetIgnoreKSPComputeOperators_Telescope));
1382: PetscCall(PetscObjectComposeFunction((PetscObject)pc, "PCTelescopeGetDM_C", PCTelescopeGetDM_Telescope));
1383: PetscCall(PetscObjectComposeFunction((PetscObject)pc, "PCTelescopeGetUseCoarseDM_C", PCTelescopeGetUseCoarseDM_Telescope));
1384: PetscCall(PetscObjectComposeFunction((PetscObject)pc, "PCTelescopeSetUseCoarseDM_C", PCTelescopeSetUseCoarseDM_Telescope));
1385: PetscFunctionReturn(PETSC_SUCCESS);
1386: }