Date: 2021-03-03T22:27:18+00:00

Actual source code: telescope_dmda.c
petsc-3.14.5 2021-03-03
Report Typos and Errors

      3: #include <petsc/private/matimpl.h>
      4: #include <petsc/private/pcimpl.h>
      5: #include <petsc/private/dmimpl.h>
      6: #include <petscksp.h>
      7: #include <petscdm.h>
      8: #include <petscdmda.h>

     10: #include "../src/ksp/pc/impls/telescope/telescope.h"

     12: static PetscBool  cited = PETSC_FALSE;
     13: static const char citation[] =
     14: "@inproceedings{MaySananRuppKnepleySmith2016,\n"
     15: "  title     = {Extreme-Scale Multigrid Components within PETSc},\n"
     16: "  author    = {Dave A. May and Patrick Sanan and Karl Rupp and Matthew G. Knepley and Barry F. Smith},\n"
     17: "  booktitle = {Proceedings of the Platform for Advanced Scientific Computing Conference},\n"
     18: "  series    = {PASC '16},\n"
     19: "  isbn      = {978-1-4503-4126-4},\n"
     20: "  location  = {Lausanne, Switzerland},\n"
     21: "  pages     = {5:1--5:12},\n"
     22: "  articleno = {5},\n"
     23: "  numpages  = {12},\n"
     24: "  url       = {https://doi.acm.org/10.1145/2929908.2929913},\n"
     25: "  doi       = {10.1145/2929908.2929913},\n"
     26: "  acmid     = {2929913},\n"
     27: "  publisher = {ACM},\n"
     28: "  address   = {New York, NY, USA},\n"
     29: "  keywords  = {GPU, HPC, agglomeration, coarse-level solver, multigrid, parallel computing, preconditioning},\n"
     30: "  year      = {2016}\n"
     31: "}\n";

     33: static PetscErrorCode _DMDADetermineRankFromGlobalIJK(PetscInt dim,PetscInt i,PetscInt j,PetscInt k,
     34:                                                       PetscInt Mp,PetscInt Np,PetscInt Pp,
     35:                                                       PetscInt start_i[],PetscInt start_j[],PetscInt start_k[],
     36:                                                       PetscInt span_i[],PetscInt span_j[],PetscInt span_k[],
     37:                                                       PetscMPIInt *_pi,PetscMPIInt *_pj,PetscMPIInt *_pk,PetscMPIInt *rank_re)
     38: {
     39:   PetscInt pi,pj,pk,n;

     42:   *rank_re = -1;
     43:   if (_pi) *_pi = -1;
     44:   if (_pj) *_pj = -1;
     45:   if (_pk) *_pk = -1;
     46:   pi = pj = pk = -1;
     47:   if (_pi) {
     48:     for (n=0; n<Mp; n++) {
     49:       if ((i >= start_i[n]) && (i < start_i[n]+span_i[n])) {
     50:         pi = n;
     51:         break;
     52:       }
     53:     }
     54:     if (pi == -1) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_USER,"[dmda-ijk] pi cannot be determined : range %D, val %D",Mp,i);
     55:     *_pi = pi;
     56:   }

     58:   if (_pj) {
     59:     for (n=0; n<Np; n++) {
     60:       if ((j >= start_j[n]) && (j < start_j[n]+span_j[n])) {
     61:         pj = n;
     62:         break;
     63:       }
     64:     }
     65:     if (pj == -1) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_USER,"[dmda-ijk] pj cannot be determined : range %D, val %D",Np,j);
     66:     *_pj = pj;
     67:   }

     69:   if (_pk) {
     70:     for (n=0; n<Pp; n++) {
     71:       if ((k >= start_k[n]) && (k < start_k[n]+span_k[n])) {
     72:         pk = n;
     73:         break;
     74:       }
     75:     }
     76:     if (pk == -1) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_USER,"[dmda-ijk] pk cannot be determined : range %D, val %D",Pp,k);
     77:     *_pk = pk;
     78:   }

     80:   switch (dim) {
     81:   case 1:
     82:     *rank_re = pi;
     83:     break;
     84:   case 2:
     85:     *rank_re = pi + pj * Mp;
     86:     break;
     87:   case 3:
     88:     *rank_re = pi + pj * Mp + pk * (Mp*Np);
     89:     break;
     90:   }
     91:   return(0);
     92: }

     94: static PetscErrorCode _DMDADetermineGlobalS0(PetscInt dim,PetscMPIInt rank_re,PetscInt Mp_re,PetscInt Np_re,PetscInt Pp_re,
     95:                                       PetscInt range_i_re[],PetscInt range_j_re[],PetscInt range_k_re[],PetscInt *s0)
     96: {
     97:   PetscInt i,j,k,start_IJK = 0;
     98:   PetscInt rank_ijk;

    101:   switch (dim) {
    102:   case 1:
    103:     for (i=0; i<Mp_re; i++) {
    104:       rank_ijk = i;
    105:       if (rank_ijk < rank_re) {
    106:         start_IJK += range_i_re[i];
    107:       }
    108:     }
    109:     break;
    110:     case 2:
    111:     for (j=0; j<Np_re; j++) {
    112:       for (i=0; i<Mp_re; i++) {
    113:         rank_ijk = i + j*Mp_re;
    114:         if (rank_ijk < rank_re) {
    115:           start_IJK += range_i_re[i]*range_j_re[j];
    116:         }
    117:       }
    118:     }
    119:     break;
    120:     case 3:
    121:     for (k=0; k<Pp_re; k++) {
    122:       for (j=0; j<Np_re; j++) {
    123:         for (i=0; i<Mp_re; i++) {
    124:           rank_ijk = i + j*Mp_re + k*Mp_re*Np_re;
    125:           if (rank_ijk < rank_re) {
    126:             start_IJK += range_i_re[i]*range_j_re[j]*range_k_re[k];
    127:           }
    128:         }
    129:       }
    130:     }
    131:     break;
    132:   }
    133:   *s0 = start_IJK;
    134:   return(0);
    135: }

    137: static PetscErrorCode PCTelescopeSetUp_dmda_repart_coors2d(PC_Telescope sred,DM dm,DM subdm)
    138: {
    140:   DM             cdm;
    141:   Vec            coor,coor_natural,perm_coors;
    142:   PetscInt       i,j,si,sj,ni,nj,M,N,Ml,Nl,c,nidx;
    143:   PetscInt       *fine_indices;
    144:   IS             is_fine,is_local;
    145:   VecScatter     sctx;

    148:   DMGetCoordinates(dm,&coor);
    149:   if (!coor) return(0);
    150:   if (PCTelescope_isActiveRank(sred)) {
    151:     DMDASetUniformCoordinates(subdm,0.0,1.0,0.0,1.0,0.0,1.0);
    152:   }
    153:   /* Get the coordinate vector from the distributed array */
    154:   DMGetCoordinateDM(dm,&cdm);
    155:   DMDACreateNaturalVector(cdm,&coor_natural);

    157:   DMDAGlobalToNaturalBegin(cdm,coor,INSERT_VALUES,coor_natural);
    158:   DMDAGlobalToNaturalEnd(cdm,coor,INSERT_VALUES,coor_natural);

    160:   /* get indices of the guys I want to grab */
    161:   DMDAGetInfo(dm,NULL,&M,&N,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL);
    162:   if (PCTelescope_isActiveRank(sred)) {
    163:     DMDAGetCorners(subdm,&si,&sj,NULL,&ni,&nj,NULL);
    164:     Ml = ni;
    165:     Nl = nj;
    166:   } else {
    167:     si = sj = 0;
    168:     ni = nj = 0;
    169:     Ml = Nl = 0;
    170:   }

    172:   PetscMalloc1(Ml*Nl*2,&fine_indices);
    173:   c = 0;
    174:   if (PCTelescope_isActiveRank(sred)) {
    175:     for (j=sj; j<sj+nj; j++) {
    176:       for (i=si; i<si+ni; i++) {
    177:         nidx = (i) + (j)*M;
    178:         fine_indices[c  ] = 2 * nidx     ;
    179:         fine_indices[c+1] = 2 * nidx + 1 ;
    180:         c = c + 2;
    181:       }
    182:     }
    183:     if (c != Ml*Nl*2) SETERRQ3(PETSC_COMM_SELF,PETSC_ERR_PLIB,"c %D should equal 2 * Ml %D * Nl %D",c,Ml,Nl);
    184:   }

    186:   /* generate scatter */
    187:   ISCreateGeneral(PetscObjectComm((PetscObject)dm),Ml*Nl*2,fine_indices,PETSC_USE_POINTER,&is_fine);
    188:   ISCreateStride(PETSC_COMM_SELF,Ml*Nl*2,0,1,&is_local);

    190:   /* scatter */
    191:   VecCreate(PETSC_COMM_SELF,&perm_coors);
    192:   VecSetSizes(perm_coors,PETSC_DECIDE,Ml*Nl*2);
    193:   VecSetType(perm_coors,VECSEQ);

    195:   VecScatterCreate(coor_natural,is_fine,perm_coors,is_local,&sctx);
    196:   VecScatterBegin(sctx,coor_natural,perm_coors,INSERT_VALUES,SCATTER_FORWARD);
    197:   VecScatterEnd(  sctx,coor_natural,perm_coors,INSERT_VALUES,SCATTER_FORWARD);
    198:   /* access */
    199:   if (PCTelescope_isActiveRank(sred)) {
    200:     Vec               _coors;
    201:     const PetscScalar *LA_perm;
    202:     PetscScalar       *LA_coors;

    204:     DMGetCoordinates(subdm,&_coors);
    205:     VecGetArrayRead(perm_coors,&LA_perm);
    206:     VecGetArray(_coors,&LA_coors);
    207:     for (i=0; i<Ml*Nl*2; i++) {
    208:       LA_coors[i] = LA_perm[i];
    209:     }
    210:     VecRestoreArray(_coors,&LA_coors);
    211:     VecRestoreArrayRead(perm_coors,&LA_perm);
    212:   }

    214:   /* update local coords */
    215:   if (PCTelescope_isActiveRank(sred)) {
    216:     DM  _dmc;
    217:     Vec _coors,_coors_local;
    218:     DMGetCoordinateDM(subdm,&_dmc);
    219:     DMGetCoordinates(subdm,&_coors);
    220:     DMGetCoordinatesLocal(subdm,&_coors_local);
    221:     DMGlobalToLocalBegin(_dmc,_coors,INSERT_VALUES,_coors_local);
    222:     DMGlobalToLocalEnd(_dmc,_coors,INSERT_VALUES,_coors_local);
    223:   }
    224:   VecScatterDestroy(&sctx);
    225:   ISDestroy(&is_fine);
    226:   PetscFree(fine_indices);
    227:   ISDestroy(&is_local);
    228:   VecDestroy(&perm_coors);
    229:   VecDestroy(&coor_natural);
    230:   return(0);
    231: }

    233: static PetscErrorCode PCTelescopeSetUp_dmda_repart_coors3d(PC_Telescope sred,DM dm,DM subdm)
    234: {
    236:   DM             cdm;
    237:   Vec            coor,coor_natural,perm_coors;
    238:   PetscInt       i,j,k,si,sj,sk,ni,nj,nk,M,N,P,Ml,Nl,Pl,c,nidx;
    239:   PetscInt       *fine_indices;
    240:   IS             is_fine,is_local;
    241:   VecScatter     sctx;

    244:   DMGetCoordinates(dm,&coor);
    245:   if (!coor) return(0);

    247:   if (PCTelescope_isActiveRank(sred)) {
    248:     DMDASetUniformCoordinates(subdm,0.0,1.0,0.0,1.0,0.0,1.0);
    249:   }

    251:   /* Get the coordinate vector from the distributed array */
    252:   DMGetCoordinateDM(dm,&cdm);
    253:   DMDACreateNaturalVector(cdm,&coor_natural);
    254:   DMDAGlobalToNaturalBegin(cdm,coor,INSERT_VALUES,coor_natural);
    255:   DMDAGlobalToNaturalEnd(cdm,coor,INSERT_VALUES,coor_natural);

    257:   /* get indices of the guys I want to grab */
    258:   DMDAGetInfo(dm,NULL,&M,&N,&P,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL);

    260:   if (PCTelescope_isActiveRank(sred)) {
    261:     DMDAGetCorners(subdm,&si,&sj,&sk,&ni,&nj,&nk);
    262:     Ml = ni;
    263:     Nl = nj;
    264:     Pl = nk;
    265:   } else {
    266:     si = sj = sk = 0;
    267:     ni = nj = nk = 0;
    268:     Ml = Nl = Pl = 0;
    269:   }

    271:   PetscMalloc1(Ml*Nl*Pl*3,&fine_indices);

    273:   c = 0;
    274:   if (PCTelescope_isActiveRank(sred)) {
    275:     for (k=sk; k<sk+nk; k++) {
    276:       for (j=sj; j<sj+nj; j++) {
    277:         for (i=si; i<si+ni; i++) {
    278:           nidx = (i) + (j)*M + (k)*M*N;
    279:           fine_indices[c  ] = 3 * nidx     ;
    280:           fine_indices[c+1] = 3 * nidx + 1 ;
    281:           fine_indices[c+2] = 3 * nidx + 2 ;
    282:           c = c + 3;
    283:         }
    284:       }
    285:     }
    286:   }

    288:   /* generate scatter */
    289:   ISCreateGeneral(PetscObjectComm((PetscObject)dm),Ml*Nl*Pl*3,fine_indices,PETSC_USE_POINTER,&is_fine);
    290:   ISCreateStride(PETSC_COMM_SELF,Ml*Nl*Pl*3,0,1,&is_local);

    292:   /* scatter */
    293:   VecCreate(PETSC_COMM_SELF,&perm_coors);
    294:   VecSetSizes(perm_coors,PETSC_DECIDE,Ml*Nl*Pl*3);
    295:   VecSetType(perm_coors,VECSEQ);
    296:   VecScatterCreate(coor_natural,is_fine,perm_coors,is_local,&sctx);
    297:   VecScatterBegin(sctx,coor_natural,perm_coors,INSERT_VALUES,SCATTER_FORWARD);
    298:   VecScatterEnd(  sctx,coor_natural,perm_coors,INSERT_VALUES,SCATTER_FORWARD);

    300:   /* access */
    301:   if (PCTelescope_isActiveRank(sred)) {
    302:     Vec               _coors;
    303:     const PetscScalar *LA_perm;
    304:     PetscScalar       *LA_coors;

    306:     DMGetCoordinates(subdm,&_coors);
    307:     VecGetArrayRead(perm_coors,&LA_perm);
    308:     VecGetArray(_coors,&LA_coors);
    309:     for (i=0; i<Ml*Nl*Pl*3; i++) {
    310:       LA_coors[i] = LA_perm[i];
    311:     }
    312:     VecRestoreArray(_coors,&LA_coors);
    313:     VecRestoreArrayRead(perm_coors,&LA_perm);
    314:   }

    316:   /* update local coords */
    317:   if (PCTelescope_isActiveRank(sred)) {
    318:     DM  _dmc;
    319:     Vec _coors,_coors_local;

    321:     DMGetCoordinateDM(subdm,&_dmc);
    322:     DMGetCoordinates(subdm,&_coors);
    323:     DMGetCoordinatesLocal(subdm,&_coors_local);
    324:     DMGlobalToLocalBegin(_dmc,_coors,INSERT_VALUES,_coors_local);
    325:     DMGlobalToLocalEnd(_dmc,_coors,INSERT_VALUES,_coors_local);
    326:   }

    328:   VecScatterDestroy(&sctx);
    329:   ISDestroy(&is_fine);
    330:   PetscFree(fine_indices);
    331:   ISDestroy(&is_local);
    332:   VecDestroy(&perm_coors);
    333:   VecDestroy(&coor_natural);
    334:   return(0);
    335: }

    337: static PetscErrorCode PCTelescopeSetUp_dmda_repart_coors(PC pc,PC_Telescope sred,PC_Telescope_DMDACtx *ctx)
    338: {
    339:   PetscInt       dim;
    340:   DM             dm,subdm;
    341:   PetscSubcomm   psubcomm;
    342:   MPI_Comm       comm;
    343:   Vec            coor;

    347:   PCGetDM(pc,&dm);
    348:   DMGetCoordinates(dm,&coor);
    349:   if (!coor) return(0);
    350:   psubcomm = sred->psubcomm;
    351:   comm = PetscSubcommParent(psubcomm);
    352:   subdm = ctx->dmrepart;

    354:   PetscInfo(pc,"PCTelescope: setting up the coordinates (DMDA)\n");
    355:   DMDAGetInfo(dm,&dim,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL);
    356:   switch (dim) {
    357:   case 1:
    358:     SETERRQ(comm,PETSC_ERR_SUP,"Telescope: DMDA (1D) repartitioning not provided");
    359:   case 2: PCTelescopeSetUp_dmda_repart_coors2d(sred,dm,subdm);
    360:     break;
    361:   case 3: PCTelescopeSetUp_dmda_repart_coors3d(sred,dm,subdm);
    362:     break;
    363:   }
    364:   return(0);
    365: }

    367: /* setup repartitioned dm */
    368: PetscErrorCode PCTelescopeSetUp_dmda_repart(PC pc,PC_Telescope sred,PC_Telescope_DMDACtx *ctx)
    369: {
    370:   PetscErrorCode        ierr;
    371:   DM                    dm;
    372:   PetscInt              dim,nx,ny,nz,ndof,nsw,sum,k;
    373:   DMBoundaryType        bx,by,bz;
    374:   DMDAStencilType       stencil;
    375:   const PetscInt        *_range_i_re;
    376:   const PetscInt        *_range_j_re;
    377:   const PetscInt        *_range_k_re;
    378:   DMDAInterpolationType itype;
    379:   PetscInt              refine_x,refine_y,refine_z;
    380:   MPI_Comm              comm,subcomm;
    381:   const char            *prefix;

    384:   comm = PetscSubcommParent(sred->psubcomm);
    385:   subcomm = PetscSubcommChild(sred->psubcomm);
    386:   PCGetDM(pc,&dm);

    388:   DMDAGetInfo(dm,&dim,&nx,&ny,&nz,NULL,NULL,NULL,&ndof,&nsw,&bx,&by,&bz,&stencil);
    389:   DMDAGetInterpolationType(dm,&itype);
    390:   DMDAGetRefinementFactor(dm,&refine_x,&refine_y,&refine_z);

    392:   ctx->dmrepart = NULL;
    393:   _range_i_re = _range_j_re = _range_k_re = NULL;
    394:   /* Create DMDA on the child communicator */
    395:   if (PCTelescope_isActiveRank(sred)) {
    396:     switch (dim) {
    397:     case 1:
    398:       PetscInfo(pc,"PCTelescope: setting up the DMDA on comm subset (1D)\n");
    399:       /*DMDACreate1d(subcomm,bx,nx,ndof,nsw,NULL,&ctx->dmrepart);*/
    400:       ny = nz = 1;
    401:       by = bz = DM_BOUNDARY_NONE;
    402:       break;
    403:     case 2:
    404:       PetscInfo(pc,"PCTelescope: setting up the DMDA on comm subset (2D)\n");
    405:       /*DMDACreate2d(subcomm,bx,by,stencil,nx,ny, PETSC_DECIDE,PETSC_DECIDE, ndof,nsw, NULL,NULL,&ctx->dmrepart);*/
    406:       nz = 1;
    407:       bz = DM_BOUNDARY_NONE;
    408:       break;
    409:     case 3:
    410:       PetscInfo(pc,"PCTelescope: setting up the DMDA on comm subset (3D)\n");
    411:       /*DMDACreate3d(subcomm,bx,by,bz,stencil,nx,ny,nz, PETSC_DECIDE,PETSC_DECIDE,PETSC_DECIDE, ndof,nsw, NULL,NULL,NULL,&ctx->dmrepart);*/
    412:       break;
    413:     }
    414:     /*
    415:      The API DMDACreate1d(), DMDACreate2d(), DMDACreate3d() does not allow us to set/append
    416:      a unique option prefix for the DM, thus I prefer to expose the contents of these API's here.
    417:      This allows users to control the partitioning of the subDM.
    418:     */
    419:     DMDACreate(subcomm,&ctx->dmrepart);
    420:     /* Set unique option prefix name */
    421:     KSPGetOptionsPrefix(sred->ksp,&prefix);
    422:     DMSetOptionsPrefix(ctx->dmrepart,prefix);
    423:     DMAppendOptionsPrefix(ctx->dmrepart,"repart_");
    424:     /* standard setup from DMDACreate{1,2,3}d() */
    425:     DMSetDimension(ctx->dmrepart,dim);
    426:     DMDASetSizes(ctx->dmrepart,nx,ny,nz);
    427:     DMDASetNumProcs(ctx->dmrepart,PETSC_DECIDE,PETSC_DECIDE,PETSC_DECIDE);
    428:     DMDASetBoundaryType(ctx->dmrepart,bx,by,bz);
    429:     DMDASetDof(ctx->dmrepart,ndof);
    430:     DMDASetStencilType(ctx->dmrepart,stencil);
    431:     DMDASetStencilWidth(ctx->dmrepart,nsw);
    432:     DMDASetOwnershipRanges(ctx->dmrepart,NULL,NULL,NULL);
    433:     DMSetFromOptions(ctx->dmrepart);
    434:     DMSetUp(ctx->dmrepart);
    435:     /* Set refinement factors and interpolation type from the partent */
    436:     DMDASetRefinementFactor(ctx->dmrepart,refine_x,refine_y,refine_z);
    437:     DMDASetInterpolationType(ctx->dmrepart,itype);

    439:     DMDAGetInfo(ctx->dmrepart,NULL,NULL,NULL,NULL,&ctx->Mp_re,&ctx->Np_re,&ctx->Pp_re,NULL,NULL,NULL,NULL,NULL,NULL);
    440:     DMDAGetOwnershipRanges(ctx->dmrepart,&_range_i_re,&_range_j_re,&_range_k_re);

    442:     ctx->dmrepart->ops->creatematrix = dm->ops->creatematrix;
    443:     ctx->dmrepart->ops->createdomaindecomposition = dm->ops->createdomaindecomposition;
    444:   }

    446:   /* generate ranges for repartitioned dm */
    447:   /* note - assume rank 0 always participates */
    448:   /* TODO: use a single MPI call */
    449:   MPI_Bcast(&ctx->Mp_re,1,MPIU_INT,0,comm);
    450:   MPI_Bcast(&ctx->Np_re,1,MPIU_INT,0,comm);
    451:   MPI_Bcast(&ctx->Pp_re,1,MPIU_INT,0,comm);

    453:   PetscCalloc3(ctx->Mp_re,&ctx->range_i_re,ctx->Np_re,&ctx->range_j_re,ctx->Pp_re,&ctx->range_k_re);

    455:   if (_range_i_re) {PetscArraycpy(ctx->range_i_re,_range_i_re,ctx->Mp_re);}
    456:   if (_range_j_re) {PetscArraycpy(ctx->range_j_re,_range_j_re,ctx->Np_re);}
    457:   if (_range_k_re) {PetscArraycpy(ctx->range_k_re,_range_k_re,ctx->Pp_re);}

    459:   /* TODO: use a single MPI call */
    460:   MPI_Bcast(ctx->range_i_re,ctx->Mp_re,MPIU_INT,0,comm);
    461:   MPI_Bcast(ctx->range_j_re,ctx->Np_re,MPIU_INT,0,comm);
    462:   MPI_Bcast(ctx->range_k_re,ctx->Pp_re,MPIU_INT,0,comm);

    464:   PetscMalloc3(ctx->Mp_re,&ctx->start_i_re,ctx->Np_re,&ctx->start_j_re,ctx->Pp_re,&ctx->start_k_re);

    466:   sum = 0;
    467:   for (k=0; k<ctx->Mp_re; k++) {
    468:     ctx->start_i_re[k] = sum;
    469:     sum += ctx->range_i_re[k];
    470:   }

    472:   sum = 0;
    473:   for (k=0; k<ctx->Np_re; k++) {
    474:     ctx->start_j_re[k] = sum;
    475:     sum += ctx->range_j_re[k];
    476:   }

    478:   sum = 0;
    479:   for (k=0; k<ctx->Pp_re; k++) {
    480:     ctx->start_k_re[k] = sum;
    481:     sum += ctx->range_k_re[k];
    482:   }

    484:   /* attach repartitioned dm to child ksp */
    485:   {
    486:     PetscErrorCode (*dmksp_func)(KSP,Mat,Mat,void*);
    487:     void           *dmksp_ctx;

    489:     DMKSPGetComputeOperators(dm,&dmksp_func,&dmksp_ctx);

    491:     /* attach dm to ksp on sub communicator */
    492:     if (PCTelescope_isActiveRank(sred)) {
    493:       KSPSetDM(sred->ksp,ctx->dmrepart);

    495:       if (!dmksp_func || sred->ignore_kspcomputeoperators) {
    496:         KSPSetDMActive(sred->ksp,PETSC_FALSE);
    497:       } else {
    498:         /* sub ksp inherits dmksp_func and context provided by user */
    499:         KSPSetComputeOperators(sred->ksp,dmksp_func,dmksp_ctx);
    500:         KSPSetDMActive(sred->ksp,PETSC_TRUE);
    501:       }
    502:     }
    503:   }
    504:   return(0);
    505: }

    507: PetscErrorCode PCTelescopeSetUp_dmda_permutation_3d(PC pc,PC_Telescope sred,PC_Telescope_DMDACtx *ctx)
    508: {
    510:   DM             dm;
    511:   MPI_Comm       comm;
    512:   Mat            Pscalar,P;
    513:   PetscInt       ndof;
    514:   PetscInt       i,j,k,location,startI[3],endI[3],lenI[3],nx,ny,nz;
    515:   PetscInt       sr,er,Mr;
    516:   Vec            V;

    519:   PetscInfo(pc,"PCTelescope: setting up the permutation matrix (DMDA-3D)\n");
    520:   PetscObjectGetComm((PetscObject)pc,&comm);

    522:   PCGetDM(pc,&dm);
    523:   DMDAGetInfo(dm,NULL,&nx,&ny,&nz,NULL,NULL,NULL,&ndof,NULL,NULL,NULL,NULL,NULL);

    525:   DMGetGlobalVector(dm,&V);
    526:   VecGetSize(V,&Mr);
    527:   VecGetOwnershipRange(V,&sr,&er);
    528:   DMRestoreGlobalVector(dm,&V);
    529:   sr = sr / ndof;
    530:   er = er / ndof;
    531:   Mr = Mr / ndof;

    533:   MatCreate(comm,&Pscalar);
    534:   MatSetSizes(Pscalar,(er-sr),(er-sr),Mr,Mr);
    535:   MatSetType(Pscalar,MATAIJ);
    536:   MatSeqAIJSetPreallocation(Pscalar,1,NULL);
    537:   MatMPIAIJSetPreallocation(Pscalar,1,NULL,1,NULL);

    539:   DMDAGetCorners(dm,NULL,NULL,NULL,&lenI[0],&lenI[1],&lenI[2]);
    540:   DMDAGetCorners(dm,&startI[0],&startI[1],&startI[2],&endI[0],&endI[1],&endI[2]);
    541:   endI[0] += startI[0];
    542:   endI[1] += startI[1];
    543:   endI[2] += startI[2];

    545:   for (k=startI[2]; k<endI[2]; k++) {
    546:     for (j=startI[1]; j<endI[1]; j++) {
    547:       for (i=startI[0]; i<endI[0]; i++) {
    548:         PetscMPIInt rank_ijk_re,rank_reI[3];
    549:         PetscInt    s0_re;
    550:         PetscInt    ii,jj,kk,local_ijk_re,mapped_ijk;
    551:         PetscInt    lenI_re[3];

    553:         location = (i - startI[0]) + (j - startI[1])*lenI[0] + (k - startI[2])*lenI[0]*lenI[1];
    554:         _DMDADetermineRankFromGlobalIJK(3,i,j,k,   ctx->Mp_re,ctx->Np_re,ctx->Pp_re,
    555:                                                ctx->start_i_re,ctx->start_j_re,ctx->start_k_re,
    556:                                                ctx->range_i_re,ctx->range_j_re,ctx->range_k_re,
    557:                                                &rank_reI[0],&rank_reI[1],&rank_reI[2],&rank_ijk_re);
    558:         _DMDADetermineGlobalS0(3,rank_ijk_re, ctx->Mp_re,ctx->Np_re,ctx->Pp_re, ctx->range_i_re,ctx->range_j_re,ctx->range_k_re, &s0_re);
    559:         ii = i - ctx->start_i_re[ rank_reI[0] ];
    560:         if (ii < 0) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_USER,"[dmdarepart-perm3d] index error ii");
    561:         jj = j - ctx->start_j_re[ rank_reI[1] ];
    562:         if (jj < 0) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_USER,"[dmdarepart-perm3d] index error jj");
    563:         kk = k - ctx->start_k_re[ rank_reI[2] ];
    564:         if (kk < 0) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_USER,"[dmdarepart-perm3d] index error kk");
    565:         lenI_re[0] = ctx->range_i_re[ rank_reI[0] ];
    566:         lenI_re[1] = ctx->range_j_re[ rank_reI[1] ];
    567:         lenI_re[2] = ctx->range_k_re[ rank_reI[2] ];
    568:         local_ijk_re = ii + jj * lenI_re[0] + kk * lenI_re[0] * lenI_re[1];
    569:         mapped_ijk = s0_re + local_ijk_re;
    570:         MatSetValue(Pscalar,sr+location,mapped_ijk,1.0,INSERT_VALUES);
    571:       }
    572:     }
    573:   }
    574:   MatAssemblyBegin(Pscalar,MAT_FINAL_ASSEMBLY);
    575:   MatAssemblyEnd(Pscalar,MAT_FINAL_ASSEMBLY);
    576:   MatCreateMAIJ(Pscalar,ndof,&P);
    577:   MatDestroy(&Pscalar);
    578:   ctx->permutation = P;
    579:   return(0);
    580: }

    582: PetscErrorCode PCTelescopeSetUp_dmda_permutation_2d(PC pc,PC_Telescope sred,PC_Telescope_DMDACtx *ctx)
    583: {
    585:   DM             dm;
    586:   MPI_Comm       comm;
    587:   Mat            Pscalar,P;
    588:   PetscInt       ndof;
    589:   PetscInt       i,j,location,startI[2],endI[2],lenI[2],nx,ny,nz;
    590:   PetscInt       sr,er,Mr;
    591:   Vec            V;

    594:   PetscInfo(pc,"PCTelescope: setting up the permutation matrix (DMDA-2D)\n");
    595:   PetscObjectGetComm((PetscObject)pc,&comm);
    596:   PCGetDM(pc,&dm);
    597:   DMDAGetInfo(dm,NULL,&nx,&ny,&nz,NULL,NULL,NULL,&ndof,NULL,NULL,NULL,NULL,NULL);
    598:   DMGetGlobalVector(dm,&V);
    599:   VecGetSize(V,&Mr);
    600:   VecGetOwnershipRange(V,&sr,&er);
    601:   DMRestoreGlobalVector(dm,&V);
    602:   sr = sr / ndof;
    603:   er = er / ndof;
    604:   Mr = Mr / ndof;

    606:   MatCreate(comm,&Pscalar);
    607:   MatSetSizes(Pscalar,(er-sr),(er-sr),Mr,Mr);
    608:   MatSetType(Pscalar,MATAIJ);
    609:   MatSeqAIJSetPreallocation(Pscalar,1,NULL);
    610:   MatMPIAIJSetPreallocation(Pscalar,1,NULL,1,NULL);

    612:   DMDAGetCorners(dm,NULL,NULL,NULL,&lenI[0],&lenI[1],NULL);
    613:   DMDAGetCorners(dm,&startI[0],&startI[1],NULL,&endI[0],&endI[1],NULL);
    614:   endI[0] += startI[0];
    615:   endI[1] += startI[1];

    617:   for (j=startI[1]; j<endI[1]; j++) {
    618:     for (i=startI[0]; i<endI[0]; i++) {
    619:       PetscMPIInt rank_ijk_re,rank_reI[3];
    620:       PetscInt    s0_re;
    621:       PetscInt    ii,jj,local_ijk_re,mapped_ijk;
    622:       PetscInt    lenI_re[3];

    624:       location = (i - startI[0]) + (j - startI[1])*lenI[0];
    625:       _DMDADetermineRankFromGlobalIJK(2,i,j,0,   ctx->Mp_re,ctx->Np_re,ctx->Pp_re,
    626:                                              ctx->start_i_re,ctx->start_j_re,ctx->start_k_re,
    627:                                              ctx->range_i_re,ctx->range_j_re,ctx->range_k_re,
    628:                                              &rank_reI[0],&rank_reI[1],NULL,&rank_ijk_re);

    630:       _DMDADetermineGlobalS0(2,rank_ijk_re, ctx->Mp_re,ctx->Np_re,ctx->Pp_re, ctx->range_i_re,ctx->range_j_re,ctx->range_k_re, &s0_re);

    632:       ii = i - ctx->start_i_re[ rank_reI[0] ];
    633:       if (ii < 0) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_USER,"[dmdarepart-perm2d] index error ii");
    634:       jj = j - ctx->start_j_re[ rank_reI[1] ];
    635:       if (jj < 0) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_USER,"[dmdarepart-perm2d] index error jj");

    637:       lenI_re[0] = ctx->range_i_re[ rank_reI[0] ];
    638:       lenI_re[1] = ctx->range_j_re[ rank_reI[1] ];
    639:       local_ijk_re = ii + jj * lenI_re[0];
    640:       mapped_ijk = s0_re + local_ijk_re;
    641:       MatSetValue(Pscalar,sr+location,mapped_ijk,1.0,INSERT_VALUES);
    642:     }
    643:   }
    644:   MatAssemblyBegin(Pscalar,MAT_FINAL_ASSEMBLY);
    645:   MatAssemblyEnd(Pscalar,MAT_FINAL_ASSEMBLY);
    646:   MatCreateMAIJ(Pscalar,ndof,&P);
    647:   MatDestroy(&Pscalar);
    648:   ctx->permutation = P;
    649:   return(0);
    650: }

    652: PetscErrorCode PCTelescopeSetUp_dmda_scatters(PC pc,PC_Telescope sred,PC_Telescope_DMDACtx *ctx)
    653: {
    655:   Vec            xred,yred,xtmp,x,xp;
    656:   VecScatter     scatter;
    657:   IS             isin;
    658:   Mat            B;
    659:   PetscInt       m,bs,st,ed;
    660:   MPI_Comm       comm;

    663:   PetscObjectGetComm((PetscObject)pc,&comm);
    664:   PCGetOperators(pc,NULL,&B);
    665:   MatCreateVecs(B,&x,NULL);
    666:   MatGetBlockSize(B,&bs);
    667:   VecDuplicate(x,&xp);
    668:   m = 0;
    669:   xred = NULL;
    670:   yred = NULL;
    671:   if (PCTelescope_isActiveRank(sred)) {
    672:     DMCreateGlobalVector(ctx->dmrepart,&xred);
    673:     VecDuplicate(xred,&yred);
    674:     VecGetOwnershipRange(xred,&st,&ed);
    675:     ISCreateStride(comm,ed-st,st,1,&isin);
    676:     VecGetLocalSize(xred,&m);
    677:   } else {
    678:     VecGetOwnershipRange(x,&st,&ed);
    679:     ISCreateStride(comm,0,st,1,&isin);
    680:   }
    681:   ISSetBlockSize(isin,bs);
    682:   VecCreate(comm,&xtmp);
    683:   VecSetSizes(xtmp,m,PETSC_DECIDE);
    684:   VecSetBlockSize(xtmp,bs);
    685:   VecSetType(xtmp,((PetscObject)x)->type_name);
    686:   VecScatterCreate(x,isin,xtmp,NULL,&scatter);
    687:   sred->xred    = xred;
    688:   sred->yred    = yred;
    689:   sred->isin    = isin;
    690:   sred->scatter = scatter;
    691:   sred->xtmp    = xtmp;

    693:   ctx->xp       = xp;
    694:   VecDestroy(&x);
    695:   return(0);
    696: }

    698: PetscErrorCode PCTelescopeSetUp_dmda(PC pc,PC_Telescope sred)
    699: {
    700:   PC_Telescope_DMDACtx *ctx;
    701:   PetscInt             dim;
    702:   DM                   dm;
    703:   MPI_Comm             comm;
    704:   PetscErrorCode       ierr;

    707:   PetscInfo(pc,"PCTelescope: setup (DMDA)\n");
    708:   PetscNew(&ctx);
    709:   sred->dm_ctx = (void*)ctx;

    711:   PetscObjectGetComm((PetscObject)pc,&comm);
    712:   PCGetDM(pc,&dm);
    713:   DMDAGetInfo(dm,&dim,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL);

    715:   PCTelescopeSetUp_dmda_repart(pc,sred,ctx);
    716:   PCTelescopeSetUp_dmda_repart_coors(pc,sred,ctx);
    717:   switch (dim) {
    718:   case 1:
    719:     SETERRQ(comm,PETSC_ERR_SUP,"Telescope: DMDA (1D) repartitioning not provided");
    720:   case 2: PCTelescopeSetUp_dmda_permutation_2d(pc,sred,ctx);
    721:     break;
    722:   case 3: PCTelescopeSetUp_dmda_permutation_3d(pc,sred,ctx);
    723:     break;
    724:   }
    725:   PCTelescopeSetUp_dmda_scatters(pc,sred,ctx);
    726:   return(0);
    727: }

    729: PetscErrorCode PCTelescopeMatCreate_dmda_dmactivefalse(PC pc,PC_Telescope sred,MatReuse reuse,Mat *A)
    730: {
    731:   PetscErrorCode       ierr;
    732:   PC_Telescope_DMDACtx *ctx;
    733:   MPI_Comm             comm,subcomm;
    734:   Mat                  Bperm,Bred,B,P;
    735:   PetscInt             nr,nc;
    736:   IS                   isrow,iscol;
    737:   Mat                  Blocal,*_Blocal;

    740:   PetscInfo(pc,"PCTelescope: updating the redundant preconditioned operator (DMDA)\n");
    741:   PetscObjectGetComm((PetscObject)pc,&comm);
    742:   subcomm = PetscSubcommChild(sred->psubcomm);
    743:   ctx = (PC_Telescope_DMDACtx*)sred->dm_ctx;

    745:   PCGetOperators(pc,NULL,&B);
    746:   MatGetSize(B,&nr,&nc);

    748:   P = ctx->permutation;
    749:   MatPtAP(B,P,MAT_INITIAL_MATRIX,1.1,&Bperm);

    751:   /* Get submatrices */
    752:   isrow = sred->isin;
    753:   ISCreateStride(comm,nc,0,1,&iscol);

    755:   MatCreateSubMatrices(Bperm,1,&isrow,&iscol,MAT_INITIAL_MATRIX,&_Blocal);
    756:   Blocal = *_Blocal;
    757:   Bred = NULL;
    758:   if (PCTelescope_isActiveRank(sred)) {
    759:     PetscInt mm;

    761:     if (reuse != MAT_INITIAL_MATRIX) {Bred = *A;}
    762:     MatGetSize(Blocal,&mm,NULL);
    763:     /* MatCreateMPIMatConcatenateSeqMat(subcomm,Blocal,PETSC_DECIDE,reuse,&Bred); */
    764:     MatCreateMPIMatConcatenateSeqMat(subcomm,Blocal,mm,reuse,&Bred);
    765:   }
    766:   *A = Bred;

    768:   ISDestroy(&iscol);
    769:   MatDestroy(&Bperm);
    770:   MatDestroyMatrices(1,&_Blocal);
    771:   return(0);
    772: }

    774: PetscErrorCode PCTelescopeMatCreate_dmda(PC pc,PC_Telescope sred,MatReuse reuse,Mat *A)
    775: {
    777:   DM             dm;
    778:   PetscErrorCode (*dmksp_func)(KSP,Mat,Mat,void*);
    779:   void           *dmksp_ctx;

    782:   PCGetDM(pc,&dm);
    783:   DMKSPGetComputeOperators(dm,&dmksp_func,&dmksp_ctx);
    784:   /* We assume that dmksp_func = NULL, is equivalent to dmActive = PETSC_FALSE */
    785:   if (dmksp_func && !sred->ignore_kspcomputeoperators) {
    786:     DM  dmrepart;
    787:     Mat Ak;

    789:     *A = NULL;
    790:     if (PCTelescope_isActiveRank(sred)) {
    791:       KSPGetDM(sred->ksp,&dmrepart);
    792:       if (reuse == MAT_INITIAL_MATRIX) {
    793:         DMCreateMatrix(dmrepart,&Ak);
    794:         *A = Ak;
    795:       } else if (reuse == MAT_REUSE_MATRIX) {
    796:         Ak = *A;
    797:       }
    798:       /*
    799:        There is no need to explicitly assemble the operator now,
    800:        the sub-KSP will call the method provided to KSPSetComputeOperators() during KSPSetUp()
    801:       */
    802:     }
    803:   } else {
    804:     PCTelescopeMatCreate_dmda_dmactivefalse(pc,sred,reuse,A);
    805:   }
    806:   return(0);
    807: }

    809: PetscErrorCode PCTelescopeSubNullSpaceCreate_dmda_Telescope(PC pc,PC_Telescope sred,MatNullSpace nullspace,MatNullSpace *sub_nullspace)
    810: {
    811:   PetscErrorCode       ierr;
    812:   PetscBool            has_const;
    813:   PetscInt             i,k,n = 0;
    814:   const Vec            *vecs;
    815:   Vec                  *sub_vecs = NULL;
    816:   MPI_Comm             subcomm;
    817:   PC_Telescope_DMDACtx *ctx;

    820:   ctx = (PC_Telescope_DMDACtx*)sred->dm_ctx;
    821:   subcomm = PetscSubcommChild(sred->psubcomm);
    822:   MatNullSpaceGetVecs(nullspace,&has_const,&n,&vecs);

    824:   if (PCTelescope_isActiveRank(sred)) {
    825:     /* create new vectors */
    826:     if (n) {
    827:       VecDuplicateVecs(sred->xred,n,&sub_vecs);
    828:     }
    829:   }

    831:   /* copy entries */
    832:   for (k=0; k<n; k++) {
    833:     const PetscScalar *x_array;
    834:     PetscScalar       *LA_sub_vec;
    835:     PetscInt          st,ed;

    837:     /* permute vector into ordering associated with re-partitioned dmda */
    838:     MatMultTranspose(ctx->permutation,vecs[k],ctx->xp);

    840:     /* pull in vector x->xtmp */
    841:     VecScatterBegin(sred->scatter,ctx->xp,sred->xtmp,INSERT_VALUES,SCATTER_FORWARD);
    842:     VecScatterEnd(sred->scatter,ctx->xp,sred->xtmp,INSERT_VALUES,SCATTER_FORWARD);

    844:     /* copy vector entries into xred */
    845:     VecGetArrayRead(sred->xtmp,&x_array);
    846:     if (sub_vecs) {
    847:       if (sub_vecs[k]) {
    848:         VecGetOwnershipRange(sub_vecs[k],&st,&ed);
    849:         VecGetArray(sub_vecs[k],&LA_sub_vec);
    850:         for (i=0; i<ed-st; i++) {
    851:           LA_sub_vec[i] = x_array[i];
    852:         }
    853:         VecRestoreArray(sub_vecs[k],&LA_sub_vec);
    854:       }
    855:     }
    856:     VecRestoreArrayRead(sred->xtmp,&x_array);
    857:   }

    859:   if (PCTelescope_isActiveRank(sred)) {
    860:     /* create new (near) nullspace for redundant object */
    861:     MatNullSpaceCreate(subcomm,has_const,n,sub_vecs,sub_nullspace);
    862:     VecDestroyVecs(n,&sub_vecs);
    863:     if (nullspace->remove) SETERRQ(PetscObjectComm((PetscObject)pc),PETSC_ERR_SUP,"Propagation of custom remove callbacks not supported when propagating (near) nullspaces with PCTelescope");
    864:     if (nullspace->rmctx) SETERRQ(PetscObjectComm((PetscObject)pc),PETSC_ERR_SUP,"Propagation of custom remove callback context not supported when propagating (near) nullspaces with PCTelescope");
    865:   }
    866:   return(0);
    867: }

    869: PetscErrorCode PCTelescopeMatNullSpaceCreate_dmda(PC pc,PC_Telescope sred,Mat sub_mat)
    870: {
    872:   Mat            B;

    875:   PCGetOperators(pc,NULL,&B);
    876:   {
    877:     MatNullSpace nullspace,sub_nullspace;
    878:     MatGetNullSpace(B,&nullspace);
    879:     if (nullspace) {
    880:       PetscInfo(pc,"PCTelescope: generating nullspace (DMDA)\n");
    881:       PCTelescopeSubNullSpaceCreate_dmda_Telescope(pc,sred,nullspace,&sub_nullspace);
    882:       if (PCTelescope_isActiveRank(sred)) {
    883:         MatSetNullSpace(sub_mat,sub_nullspace);
    884:         MatNullSpaceDestroy(&sub_nullspace);
    885:       }
    886:     }
    887:   }
    888:   {
    889:     MatNullSpace nearnullspace,sub_nearnullspace;
    890:     MatGetNearNullSpace(B,&nearnullspace);
    891:     if (nearnullspace) {
    892:       PetscInfo(pc,"PCTelescope: generating near nullspace (DMDA)\n");
    893:       PCTelescopeSubNullSpaceCreate_dmda_Telescope(pc,sred,nearnullspace,&sub_nearnullspace);
    894:       if (PCTelescope_isActiveRank(sred)) {
    895:         MatSetNearNullSpace(sub_mat,sub_nearnullspace);
    896:         MatNullSpaceDestroy(&sub_nearnullspace);
    897:       }
    898:     }
    899:   }
    900:   return(0);
    901: }

    903: PetscErrorCode PCApply_Telescope_dmda(PC pc,Vec x,Vec y)
    904: {
    905:   PC_Telescope         sred = (PC_Telescope)pc->data;
    906:   PetscErrorCode       ierr;
    907:   Mat                  perm;
    908:   Vec                  xtmp,xp,xred,yred;
    909:   PetscInt             i,st,ed;
    910:   VecScatter           scatter;
    911:   PetscScalar          *array;
    912:   const PetscScalar    *x_array;
    913:   PC_Telescope_DMDACtx *ctx;

    915:   ctx = (PC_Telescope_DMDACtx*)sred->dm_ctx;
    916:   xtmp    = sred->xtmp;
    917:   scatter = sred->scatter;
    918:   xred    = sred->xred;
    919:   yred    = sred->yred;
    920:   perm    = ctx->permutation;
    921:   xp      = ctx->xp;

    924:   PetscCitationsRegister(citation,&cited);

    926:   /* permute vector into ordering associated with re-partitioned dmda */
    927:   MatMultTranspose(perm,x,xp);

    929:   /* pull in vector x->xtmp */
    930:   VecScatterBegin(scatter,xp,xtmp,INSERT_VALUES,SCATTER_FORWARD);
    931:   VecScatterEnd(scatter,xp,xtmp,INSERT_VALUES,SCATTER_FORWARD);

    933:   /* copy vector entires into xred */
    934:   VecGetArrayRead(xtmp,&x_array);
    935:   if (xred) {
    936:     PetscScalar *LA_xred;
    937:     VecGetOwnershipRange(xred,&st,&ed);

    939:     VecGetArray(xred,&LA_xred);
    940:     for (i=0; i<ed-st; i++) {
    941:       LA_xred[i] = x_array[i];
    942:     }
    943:     VecRestoreArray(xred,&LA_xred);
    944:   }
    945:   VecRestoreArrayRead(xtmp,&x_array);

    947:   /* solve */
    948:   if (PCTelescope_isActiveRank(sred)) {
    949:     KSPSolve(sred->ksp,xred,yred);
    950:     KSPCheckSolve(sred->ksp,pc,yred);
    951:   }

    953:   /* return vector */
    954:   VecGetArray(xtmp,&array);
    955:   if (yred) {
    956:     const PetscScalar *LA_yred;
    957:     VecGetOwnershipRange(yred,&st,&ed);
    958:     VecGetArrayRead(yred,&LA_yred);
    959:     for (i=0; i<ed-st; i++) {
    960:       array[i] = LA_yred[i];
    961:     }
    962:     VecRestoreArrayRead(yred,&LA_yred);
    963:   }
    964:   VecRestoreArray(xtmp,&array);
    965:   VecScatterBegin(scatter,xtmp,xp,INSERT_VALUES,SCATTER_REVERSE);
    966:   VecScatterEnd(scatter,xtmp,xp,INSERT_VALUES,SCATTER_REVERSE);
    967:   MatMult(perm,xp,y);
    968:   return(0);
    969: }

    971: PetscErrorCode PCApplyRichardson_Telescope_dmda(PC pc,Vec x,Vec y,Vec w,PetscReal rtol,PetscReal abstol, PetscReal dtol,PetscInt its,PetscBool zeroguess,PetscInt *outits,PCRichardsonConvergedReason *reason)
    972: {
    973:   PC_Telescope         sred = (PC_Telescope)pc->data;
    974:   PetscErrorCode       ierr;
    975:   Mat                  perm;
    976:   Vec                  xtmp,xp,yred;
    977:   PetscInt             i,st,ed;
    978:   VecScatter           scatter;
    979:   const PetscScalar    *x_array;
    980:   PetscBool            default_init_guess_value = PETSC_FALSE;
    981:   PC_Telescope_DMDACtx *ctx;

    984:   ctx = (PC_Telescope_DMDACtx*)sred->dm_ctx;
    985:   xtmp    = sred->xtmp;
    986:   scatter = sred->scatter;
    987:   yred    = sred->yred;
    988:   perm    = ctx->permutation;
    989:   xp      = ctx->xp;

    991:   if (its > 1) SETERRQ(PetscObjectComm((PetscObject)pc),PETSC_ERR_SUP,"PCApplyRichardson_Telescope_dmda only supports max_it = 1");
    992:   *reason = (PCRichardsonConvergedReason)0;

    994:   if (!zeroguess) {
    995:     PetscInfo(pc,"PCTelescopeDMDA: Scattering y for non-zero-initial guess\n");
    996:     /* permute vector into ordering associated with re-partitioned dmda */
    997:     MatMultTranspose(perm,y,xp);

    999:     /* pull in vector x->xtmp */
    1000:     VecScatterBegin(scatter,xp,xtmp,INSERT_VALUES,SCATTER_FORWARD);
    1001:     VecScatterEnd(scatter,xp,xtmp,INSERT_VALUES,SCATTER_FORWARD);

    1003:     /* copy vector entires into xred */
    1004:     VecGetArrayRead(xtmp,&x_array);
    1005:     if (yred) {
    1006:       PetscScalar *LA_yred;
    1007:       VecGetOwnershipRange(yred,&st,&ed);
    1008:       VecGetArray(yred,&LA_yred);
    1009:       for (i=0; i<ed-st; i++) {
    1010:         LA_yred[i] = x_array[i];
    1011:       }
    1012:       VecRestoreArray(yred,&LA_yred);
    1013:     }
    1014:     VecRestoreArrayRead(xtmp,&x_array);
    1015:   }

    1017:   if (PCTelescope_isActiveRank(sred)) {
    1018:     KSPGetInitialGuessNonzero(sred->ksp,&default_init_guess_value);
    1019:     if (!zeroguess) KSPSetInitialGuessNonzero(sred->ksp,PETSC_TRUE);
    1020:   }

    1022:   PCApply_Telescope_dmda(pc,x,y);

    1024:   if (PCTelescope_isActiveRank(sred)) {
    1025:     KSPSetInitialGuessNonzero(sred->ksp,default_init_guess_value);
    1026:   }

    1028:   if (!*reason) *reason = PCRICHARDSON_CONVERGED_ITS;
    1029:   *outits = 1;
    1030:   return(0);
    1031: }

    1033: PetscErrorCode PCReset_Telescope_dmda(PC pc)
    1034: {
    1035:   PetscErrorCode       ierr;
    1036:   PC_Telescope         sred = (PC_Telescope)pc->data;
    1037:   PC_Telescope_DMDACtx *ctx;

    1040:   ctx = (PC_Telescope_DMDACtx*)sred->dm_ctx;
    1041:   VecDestroy(&ctx->xp);
    1042:   MatDestroy(&ctx->permutation);
    1043:   DMDestroy(&ctx->dmrepart);
    1044:   PetscFree3(ctx->range_i_re,ctx->range_j_re,ctx->range_k_re);
    1045:   PetscFree3(ctx->start_i_re,ctx->start_j_re,ctx->start_k_re);
    1046:   return(0);
    1047: }

    1049: PetscErrorCode DMView_DA_Short_3d(DM dm,PetscViewer v)
    1050: {
    1051:   PetscInt       M,N,P,m,n,p,ndof,nsw;
    1052:   MPI_Comm       comm;
    1053:   PetscMPIInt    size;
    1054:   const char*    prefix;

    1058:   PetscObjectGetComm((PetscObject)dm,&comm);
    1059:   MPI_Comm_size(comm,&size);
    1060:   DMGetOptionsPrefix(dm,&prefix);
    1061:   DMDAGetInfo(dm,NULL,&M,&N,&P,&m,&n,&p,&ndof,&nsw,NULL,NULL,NULL,NULL);
    1062:   if (prefix) {PetscViewerASCIIPrintf(v,"DMDA Object:    (%s)    %d MPI processes\n",prefix,size);}
    1063:   else {PetscViewerASCIIPrintf(v,"DMDA Object:    %d MPI processes\n",size);}
    1064:   PetscViewerASCIIPrintf(v,"  M %D N %D P %D m %D n %D p %D dof %D overlap %D\n",M,N,P,m,n,p,ndof,nsw);
    1065:   return(0);
    1066: }

    1068: PetscErrorCode DMView_DA_Short_2d(DM dm,PetscViewer v)
    1069: {
    1070:   PetscInt       M,N,m,n,ndof,nsw;
    1071:   MPI_Comm       comm;
    1072:   PetscMPIInt    size;
    1073:   const char*    prefix;

    1077:   PetscObjectGetComm((PetscObject)dm,&comm);
    1078:   MPI_Comm_size(comm,&size);
    1079:   DMGetOptionsPrefix(dm,&prefix);
    1080:   DMDAGetInfo(dm,NULL,&M,&N,NULL,&m,&n,NULL,&ndof,&nsw,NULL,NULL,NULL,NULL);
    1081:   if (prefix) {PetscViewerASCIIPrintf(v,"DMDA Object:    (%s)    %d MPI processes\n",prefix,size);}
    1082:   else {PetscViewerASCIIPrintf(v,"DMDA Object:    %d MPI processes\n",size);}
    1083:   PetscViewerASCIIPrintf(v,"  M %D N %D m %D n %D dof %D overlap %D\n",M,N,m,n,ndof,nsw);
    1084:   return(0);
    1085: }

    1087: PetscErrorCode DMView_DA_Short(DM dm,PetscViewer v)
    1088: {
    1090:   PetscInt       dim;

    1093:   DMDAGetInfo(dm,&dim,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL);
    1094:   switch (dim) {
    1095:   case 2: DMView_DA_Short_2d(dm,v);
    1096:     break;
    1097:   case 3: DMView_DA_Short_3d(dm,v);
    1098:     break;
    1099:   }
    1100:   return(0);
    1101: }