Actual source code: isltog.c

  1: #define PETSCVEC_DLL

 3:  #include petscvec.h
 4:  #include src/vec/is/isimpl.h

  6: PetscCookie PETSCVEC_DLLEXPORT IS_LTOGM_COOKIE = -1;

 10: /*@C
 11:     ISLocalToGlobalMappingGetSize - Gets the local size of a local to global mapping.

 13:     Not Collective

 15:     Input Parameter:
 16: .   ltog - local to global mapping

 18:     Output Parameter:
 19: .   n - the number of entries in the local mapping

 21:     Level: advanced

 23:     Concepts: mapping^local to global

 25: .seealso: ISLocalToGlobalMappingDestroy(), ISLocalToGlobalMappingCreate()
 26: @*/
 27: PetscErrorCode PETSCVEC_DLLEXPORT ISLocalToGlobalMappingGetSize(ISLocalToGlobalMapping mapping,PetscInt *n)
 28: {
 32:   *n = mapping->n;
 33:   return(0);
 34: }

 38: /*@C
 39:     ISLocalToGlobalMappingView - View a local to global mapping

 41:     Not Collective

 43:     Input Parameters:
 44: +   ltog - local to global mapping
 45: -   viewer - viewer

 47:     Level: advanced

 49:     Concepts: mapping^local to global

 51: .seealso: ISLocalToGlobalMappingDestroy(), ISLocalToGlobalMappingCreate()
 52: @*/
 53: PetscErrorCode PETSCVEC_DLLEXPORT ISLocalToGlobalMappingView(ISLocalToGlobalMapping mapping,PetscViewer viewer)
 54: {
 55:   PetscInt        i;
 56:   PetscMPIInt     rank;
 57:   PetscTruth      iascii;
 58:   PetscErrorCode  ierr;

 62:   if (!viewer) viewer = PETSC_VIEWER_STDOUT_(mapping->comm);

 65:   MPI_Comm_rank(mapping->comm,&rank);
 66:   PetscTypeCompare((PetscObject)viewer,PETSC_VIEWER_ASCII,&iascii);
 67:   if (iascii) {
 68:     for (i=0; i<mapping->n; i++) {
 69:       PetscViewerASCIISynchronizedPrintf(viewer,"[%d] %d %d\n",rank,i,mapping->indices[i]);
 70:     }
 71:     PetscViewerFlush(viewer);
 72:   } else {
 73:     SETERRQ1(PETSC_ERR_SUP,"Viewer type %s not supported for ISLocalToGlobalMapping",((PetscObject)viewer)->type_name);
 74:   }

 76:   return(0);
 77: }

 81: /*@
 82:     ISLocalToGlobalMappingCreateIS - Creates a mapping between a local (0 to n)
 83:     ordering and a global parallel ordering.

 85:     Not collective

 87:     Input Parameter:
 88: .   is - index set containing the global numbers for each local

 90:     Output Parameter:
 91: .   mapping - new mapping data structure

 93:     Level: advanced

 95:     Concepts: mapping^local to global

 97: .seealso: ISLocalToGlobalMappingDestroy(), ISLocalToGlobalMappingCreate()
 98: @*/
 99: PetscErrorCode PETSCVEC_DLLEXPORT ISLocalToGlobalMappingCreateIS(IS is,ISLocalToGlobalMapping *mapping)
100: {
102:   PetscInt      n,*indices;
103:   MPI_Comm comm;


109:   PetscObjectGetComm((PetscObject)is,&comm);
110:   ISGetLocalSize(is,&n);
111:   ISGetIndices(is,&indices);
112:   ISLocalToGlobalMappingCreate(comm,n,indices,mapping);
113:   ISRestoreIndices(is,&indices);

115:   return(0);
116: }


121: /*@
122:     ISLocalToGlobalMappingCreate - Creates a mapping between a local (0 to n)
123:     ordering and a global parallel ordering.

125:     Not Collective, but communicator may have more than one process

127:     Input Parameters:
128: +   comm - MPI communicator
129: .   n - the number of local elements
130: -   indices - the global index for each local element

132:     Output Parameter:
133: .   mapping - new mapping data structure

135:     Level: advanced

137:     Concepts: mapping^local to global

139: .seealso: ISLocalToGlobalMappingDestroy(), ISLocalToGlobalMappingCreateIS(), ISLocalToGlobalMappingCreateNC()
140: @*/
141: PetscErrorCode PETSCVEC_DLLEXPORT ISLocalToGlobalMappingCreate(MPI_Comm cm,PetscInt n,const PetscInt indices[],ISLocalToGlobalMapping *mapping)
142: {
144:   PetscInt       *in;

149:   PetscMalloc(n*sizeof(PetscInt),&in);
150:   PetscMemcpy(in,indices,n*sizeof(PetscInt));
151:   ISLocalToGlobalMappingCreateNC(cm,n,in,mapping);
152:   return(0);
153: }

157: /*@C
158:     ISLocalToGlobalMappingCreateNC - Creates a mapping between a local (0 to n)
159:     ordering and a global parallel ordering.

161:     Not Collective, but communicator may have more than one process

163:     Input Parameters:
164: +   comm - MPI communicator
165: .   n - the number of local elements
166: -   indices - the global index for each local element

168:     Output Parameter:
169: .   mapping - new mapping data structure

171:     Level: developer

173:     Notes: Does not copy the indices, just keeps the pointer to the indices. The ISLocalToGlobalMappingDestroy()
174:     will free the space so it must be obtained with PetscMalloc() and it must not be freed elsewhere.

176:     Concepts: mapping^local to global

178: .seealso: ISLocalToGlobalMappingDestroy(), ISLocalToGlobalMappingCreateIS(), ISLocalToGlobalMappingCreate()
179: @*/
180: PetscErrorCode PETSCVEC_DLLEXPORT ISLocalToGlobalMappingCreateNC(MPI_Comm cm,PetscInt n,const PetscInt indices[],ISLocalToGlobalMapping *mapping)
181: {

185:   if (n) {
187:   }
189:   *mapping = PETSC_NULL;
190: #ifndef PETSC_USE_DYNAMIC_LIBRARIES
191:   VecInitializePackage(PETSC_NULL);
192: #endif
193:   if (IS_LTOGM_COOKIE == -1) {
194:     PetscLogClassRegister(&IS_LTOGM_COOKIE,"IS Local to global mapping");
195:   }

197:   PetscHeaderCreate(*mapping,_p_ISLocalToGlobalMapping,int,IS_LTOGM_COOKIE,0,"ISLocalToGlobalMapping",
198:                     cm,ISLocalToGlobalMappingDestroy,ISLocalToGlobalMappingView);
199:   PetscLogObjectMemory(*mapping,sizeof(struct _p_ISLocalToGlobalMapping)+n*sizeof(PetscInt));

201:   (*mapping)->n       = n;
202:   (*mapping)->indices = (PetscInt*)indices;

204:   /*
205:       Do not create the global to local mapping. This is only created if 
206:      ISGlobalToLocalMapping() is called 
207:   */
208:   (*mapping)->globals = 0;
209:   return(0);
210: }

214: /*@
215:     ISLocalToGlobalMappingBlock - Creates a blocked index version of an 
216:        ISLocalToGlobalMapping that is appropriate for MatSetLocalToGlobalMappingBlock()
217:        and VecSetLocalToGlobalMappingBlock().

219:     Not Collective, but communicator may have more than one process

221:     Input Parameters:
222: +    inmap - original point-wise mapping
223: -    bs - block size

225:     Output Parameter:
226: .   outmap - block based mapping; the indices are relative to BLOCKS, not individual vector or matrix entries.

228:     Level: advanced

230:     Concepts: mapping^local to global

232: .seealso: ISLocalToGlobalMappingDestroy(), ISLocalToGlobalMappingCreate(), ISLocalToGlobalMappingCreateIS()
233: @*/
234: PetscErrorCode PETSCVEC_DLLEXPORT ISLocalToGlobalMappingBlock(ISLocalToGlobalMapping inmap,PetscInt bs,ISLocalToGlobalMapping *outmap)
235: {
237:   PetscInt       *ii,i,n;

240:   if (bs > 1) {
241:     n    = inmap->n/bs;
242:     if (n*bs != inmap->n) SETERRQ(PETSC_ERR_ARG_INCOMP,"Pointwise mapping length is not divisible by block size");
243:     PetscMalloc(n*sizeof(PetscInt),&ii);
244:     for (i=0; i<n; i++) {
245:       ii[i] = inmap->indices[bs*i]/bs;
246:     }
247:     ISLocalToGlobalMappingCreate(inmap->comm,n,ii,outmap);
248:     PetscFree(ii);
249:   } else {
250:     *outmap = inmap;
251:     PetscObjectReference((PetscObject)inmap);
252:   }
253:   return(0);
254: }
255: 
258: /*@
259:    ISLocalToGlobalMappingDestroy - Destroys a mapping between a local (0 to n)
260:    ordering and a global parallel ordering.

262:    Note Collective

264:    Input Parameters:
265: .  mapping - mapping data structure

267:    Level: advanced

269: .seealso: ISLocalToGlobalMappingCreate()
270: @*/
271: PetscErrorCode PETSCVEC_DLLEXPORT ISLocalToGlobalMappingDestroy(ISLocalToGlobalMapping mapping)
272: {
276:   if (--mapping->refct > 0) return(0);
277:   if (mapping->refct < 0) {
278:     SETERRQ(PETSC_ERR_PLIB,"Mapping already destroyed");
279:   }

281:   PetscFree(mapping->indices);
282:   PetscFree(mapping->globals);
283:   PetscHeaderDestroy(mapping);
284:   return(0);
285: }
286: 
289: /*@
290:     ISLocalToGlobalMappingApplyIS - Creates from an IS in the local numbering
291:     a new index set using the global numbering defined in an ISLocalToGlobalMapping
292:     context.

294:     Not collective

296:     Input Parameters:
297: +   mapping - mapping between local and global numbering
298: -   is - index set in local numbering

300:     Output Parameters:
301: .   newis - index set in global numbering

303:     Level: advanced

305:     Concepts: mapping^local to global

307: .seealso: ISLocalToGlobalMappingApply(), ISLocalToGlobalMappingCreate(),
308:           ISLocalToGlobalMappingDestroy(), ISGlobalToLocalMappingApply()
309: @*/
310: PetscErrorCode PETSCVEC_DLLEXPORT ISLocalToGlobalMappingApplyIS(ISLocalToGlobalMapping mapping,IS is,IS *newis)
311: {
313:   PetscInt            n,i,*idxin,*idxmap,*idxout,Nmax = mapping->n;


320:   ISGetLocalSize(is,&n);
321:   ISGetIndices(is,&idxin);
322:   idxmap = mapping->indices;
323: 
324:   PetscMalloc(n*sizeof(PetscInt),&idxout);
325:   for (i=0; i<n; i++) {
326:     if (idxin[i] >= Nmax) SETERRQ3(PETSC_ERR_ARG_OUTOFRANGE,"Local index %d too large %d (max) at %d",idxin[i],Nmax-1,i);
327:     idxout[i] = idxmap[idxin[i]];
328:   }
329:   ISRestoreIndices(is,&idxin);
330:   ISCreateGeneral(PETSC_COMM_SELF,n,idxout,newis);
331:   PetscFree(idxout);
332:   return(0);
333: }

335: /*MC
336:    ISLocalToGlobalMappingApply - Takes a list of integers in a local numbering
337:    and converts them to the global numbering.

339:    Not collective

341:    Input Parameters:
342: +  mapping - the local to global mapping context
343: .  N - number of integers
344: -  in - input indices in local numbering

346:    Output Parameter:
347: .  out - indices in global numbering

349:    Synopsis:
350:    PetscErrorCode ISLocalToGlobalMappingApply(ISLocalToGlobalMapping mapping,int N,int in[],int out[])

352:    Notes: 
353:    The in and out array parameters may be identical.

355:    Level: advanced

357: .seealso: ISLocalToGlobalMappingCreate(),ISLocalToGlobalMappingDestroy(), 
358:           ISLocalToGlobalMappingApplyIS(),AOCreateBasic(),AOApplicationToPetsc(),
359:           AOPetscToApplication(), ISGlobalToLocalMappingApply()

361:     Concepts: mapping^local to global

363: M*/

365: /* -----------------------------------------------------------------------------------------*/

369: /*
370:     Creates the global fields in the ISLocalToGlobalMapping structure
371: */
372: static PetscErrorCode ISGlobalToLocalMappingSetUp_Private(ISLocalToGlobalMapping mapping)
373: {
375:   PetscInt            i,*idx = mapping->indices,n = mapping->n,end,start,*globals;

378:   end   = 0;
379:   start = 100000000;

381:   for (i=0; i<n; i++) {
382:     if (idx[i] < 0) continue;
383:     if (idx[i] < start) start = idx[i];
384:     if (idx[i] > end)   end   = idx[i];
385:   }
386:   if (start > end) {start = 0; end = -1;}
387:   mapping->globalstart = start;
388:   mapping->globalend   = end;

390:   PetscMalloc((end-start+2)*sizeof(PetscInt),&globals);
391:   mapping->globals = globals;
392:   for (i=0; i<end-start+1; i++) {
393:     globals[i] = -1;
394:   }
395:   for (i=0; i<n; i++) {
396:     if (idx[i] < 0) continue;
397:     globals[idx[i] - start] = i;
398:   }

400:   PetscLogObjectMemory(mapping,(end-start+1)*sizeof(PetscInt));
401:   return(0);
402: }

406: /*@
407:     ISGlobalToLocalMappingApply - Provides the local numbering for a list of integers
408:     specified with a global numbering.

410:     Not collective

412:     Input Parameters:
413: +   mapping - mapping between local and global numbering
414: .   type - IS_GTOLM_MASK - replaces global indices with no local value with -1
415:            IS_GTOLM_DROP - drops the indices with no local value from the output list
416: .   n - number of global indices to map
417: -   idx - global indices to map

419:     Output Parameters:
420: +   nout - number of indices in output array (if type == IS_GTOLM_MASK then nout = n)
421: -   idxout - local index of each global index, one must pass in an array long enough 
422:              to hold all the indices. You can call ISGlobalToLocalMappingApply() with 
423:              idxout == PETSC_NULL to determine the required length (returned in nout)
424:              and then allocate the required space and call ISGlobalToLocalMappingApply()
425:              a second time to set the values.

427:     Notes:
428:     Either nout or idxout may be PETSC_NULL. idx and idxout may be identical.

430:     This is not scalable in memory usage. Each processor requires O(Nglobal) size 
431:     array to compute these.

433:     Level: advanced

435:     Concepts: mapping^global to local

437: .seealso: ISLocalToGlobalMappingApply(), ISLocalToGlobalMappingCreate(),
438:           ISLocalToGlobalMappingDestroy()
439: @*/
440: PetscErrorCode PETSCVEC_DLLEXPORT ISGlobalToLocalMappingApply(ISLocalToGlobalMapping mapping,ISGlobalToLocalMappingType type,
441:                                   PetscInt n,const PetscInt idx[],PetscInt *nout,PetscInt idxout[])
442: {
443:   PetscInt i,*globals,nf = 0,tmp,start,end;

447:   if (!mapping->globals) {
448:     ISGlobalToLocalMappingSetUp_Private(mapping);
449:   }
450:   globals = mapping->globals;
451:   start   = mapping->globalstart;
452:   end     = mapping->globalend;

454:   if (type == IS_GTOLM_MASK) {
455:     if (idxout) {
456:       for (i=0; i<n; i++) {
457:         if (idx[i] < 0) idxout[i] = idx[i];
458:         else if (idx[i] < start) idxout[i] = -1;
459:         else if (idx[i] > end)   idxout[i] = -1;
460:         else                     idxout[i] = globals[idx[i] - start];
461:       }
462:     }
463:     if (nout) *nout = n;
464:   } else {
465:     if (idxout) {
466:       for (i=0; i<n; i++) {
467:         if (idx[i] < 0) continue;
468:         if (idx[i] < start) continue;
469:         if (idx[i] > end) continue;
470:         tmp = globals[idx[i] - start];
471:         if (tmp < 0) continue;
472:         idxout[nf++] = tmp;
473:       }
474:     } else {
475:       for (i=0; i<n; i++) {
476:         if (idx[i] < 0) continue;
477:         if (idx[i] < start) continue;
478:         if (idx[i] > end) continue;
479:         tmp = globals[idx[i] - start];
480:         if (tmp < 0) continue;
481:         nf++;
482:       }
483:     }
484:     if (nout) *nout = nf;
485:   }

487:   return(0);
488: }

492: /*@C
493:     ISLocalToGlobalMappingGetInfo - Gets the neighbor information for each processor and 
494:      each index shared by more than one processor 

496:     Collective on ISLocalToGlobalMapping

498:     Input Parameters:
499: .   mapping - the mapping from local to global indexing

501:     Output Parameter:
502: +   nproc - number of processors that are connected to this one
503: .   proc - neighboring processors
504: .   numproc - number of indices for each subdomain (processor)
505: -   indices - indices of local nodes shared with neighbor (sorted by global numbering)

507:     Level: advanced

509:     Concepts: mapping^local to global

511: .seealso: ISLocalToGlobalMappingDestroy(), ISLocalToGlobalMappingCreateIS(), ISLocalToGlobalMappingCreate(),
512:           ISLocalToGlobalMappingRestoreInfo()
513: @*/
514: PetscErrorCode PETSCVEC_DLLEXPORT ISLocalToGlobalMappingGetInfo(ISLocalToGlobalMapping mapping,PetscInt *nproc,PetscInt *procs[],PetscInt *numprocs[],PetscInt **indices[])
515: {
517:   PetscMPIInt    size,rank,tag1,tag2,tag3,*len,*source,imdex;
518:   PetscInt       i,n = mapping->n,Ng,ng,max = 0,*lindices = mapping->indices;
519:   PetscInt       *nprocs,*owner,nsends,*sends,j,*starts,nmax,nrecvs,*recvs,proc;
520:   PetscInt       cnt,scale,*ownedsenders,*nownedsenders,rstart,nowned;
521:   PetscInt       node,nownedm,nt,*sends2,nsends2,*starts2,*lens2,*dest,nrecvs2,*starts3,*recvs2,k,*bprocs,*tmp;
522:   PetscInt       first_procs,first_numprocs,*first_indices;
523:   MPI_Request    *recv_waits,*send_waits;
524:   MPI_Status     recv_status,*send_status,*recv_statuses;
525:   MPI_Comm       comm = mapping->comm;
526:   PetscTruth     debug = PETSC_FALSE;

529:   MPI_Comm_size(comm,&size);
530:   MPI_Comm_rank(comm,&rank);
531:   if (size == 1) {
532:     *nproc         = 0;
533:     *procs         = PETSC_NULL;
534:     PetscMalloc(sizeof(PetscInt),numprocs);
535:     (*numprocs)[0] = 0;
536:     PetscMalloc(sizeof(PetscInt*),indices);
537:     (*indices)[0]  = PETSC_NULL;
538:     return(0);
539:   }

541:   PetscOptionsHasName(PETSC_NULL,"-islocaltoglobalmappinggetinfo_debug",&debug);

543:   /*
544:     Notes on ISLocalToGlobalMappingGetInfo

546:     globally owned node - the nodes that have been assigned to this processor in global
547:            numbering, just for this routine.

549:     nontrivial globally owned node - node assigned to this processor that is on a subdomain
550:            boundary (i.e. is has more than one local owner)

552:     locally owned node - node that exists on this processors subdomain

554:     nontrivial locally owned node - node that is not in the interior (i.e. has more than one
555:            local subdomain
556:   */
557:   PetscObjectGetNewTag((PetscObject)mapping,&tag1);
558:   PetscObjectGetNewTag((PetscObject)mapping,&tag2);
559:   PetscObjectGetNewTag((PetscObject)mapping,&tag3);

561:   for (i=0; i<n; i++) {
562:     if (lindices[i] > max) max = lindices[i];
563:   }
564:   MPI_Allreduce(&max,&Ng,1,MPIU_INT,MPI_MAX,comm);
565:   Ng++;
566:   MPI_Comm_size(comm,&size);
567:   MPI_Comm_rank(comm,&rank);
568:   scale  = Ng/size + 1;
569:   ng     = scale; if (rank == size-1) ng = Ng - scale*(size-1); ng = PetscMax(1,ng);
570:   rstart = scale*rank;

572:   /* determine ownership ranges of global indices */
573:   PetscMalloc(2*size*sizeof(PetscInt),&nprocs);
574:   PetscMemzero(nprocs,2*size*sizeof(PetscInt));

576:   /* determine owners of each local node  */
577:   PetscMalloc(n*sizeof(PetscInt),&owner);
578:   for (i=0; i<n; i++) {
579:     proc             = lindices[i]/scale; /* processor that globally owns this index */
580:     nprocs[2*proc+1] = 1;                 /* processor globally owns at least one of ours */
581:     owner[i]         = proc;
582:     nprocs[2*proc]++;                     /* count of how many that processor globally owns of ours */
583:   }
584:   nsends = 0; for (i=0; i<size; i++) nsends += nprocs[2*i+1];
585:   PetscInfo1(0,"Number of global owners for my local data %d\n",nsends);

587:   /* inform other processors of number of messages and max length*/
588:   PetscMaxSum(comm,nprocs,&nmax,&nrecvs);
589:   PetscInfo1(0,"Number of local owners for my global data %d\n",nrecvs);

591:   /* post receives for owned rows */
592:   PetscMalloc((2*nrecvs+1)*(nmax+1)*sizeof(PetscInt),&recvs);
593:   PetscMalloc((nrecvs+1)*sizeof(MPI_Request),&recv_waits);
594:   for (i=0; i<nrecvs; i++) {
595:     MPI_Irecv(recvs+2*nmax*i,2*nmax,MPIU_INT,MPI_ANY_SOURCE,tag1,comm,recv_waits+i);
596:   }

598:   /* pack messages containing lists of local nodes to owners */
599:   PetscMalloc((2*n+1)*sizeof(PetscInt),&sends);
600:   PetscMalloc((size+1)*sizeof(PetscInt),&starts);
601:   starts[0]  = 0;
602:   for (i=1; i<size; i++) { starts[i] = starts[i-1] + 2*nprocs[2*i-2];}
603:   for (i=0; i<n; i++) {
604:     sends[starts[owner[i]]++] = lindices[i];
605:     sends[starts[owner[i]]++] = i;
606:   }
607:   PetscFree(owner);
608:   starts[0]  = 0;
609:   for (i=1; i<size; i++) { starts[i] = starts[i-1] + 2*nprocs[2*i-2];}

611:   /* send the messages */
612:   PetscMalloc((nsends+1)*sizeof(MPI_Request),&send_waits);
613:   PetscMalloc((nsends+1)*sizeof(PetscInt),&dest);
614:   cnt = 0;
615:   for (i=0; i<size; i++) {
616:     if (nprocs[2*i]) {
617:       MPI_Isend(sends+starts[i],2*nprocs[2*i],MPIU_INT,i,tag1,comm,send_waits+cnt);
618:       dest[cnt] = i;
619:       cnt++;
620:     }
621:   }
622:   PetscFree(starts);

624:   /* wait on receives */
625:   PetscMalloc((nrecvs+1)*sizeof(PetscMPIInt),&source);
626:   PetscMalloc((nrecvs+1)*sizeof(PetscMPIInt),&len);
627:   cnt  = nrecvs;
628:   PetscMalloc((ng+1)*sizeof(PetscInt),&nownedsenders);
629:   PetscMemzero(nownedsenders,ng*sizeof(PetscInt));
630:   while (cnt) {
631:     MPI_Waitany(nrecvs,recv_waits,&imdex,&recv_status);
632:     /* unpack receives into our local space */
633:     MPI_Get_count(&recv_status,MPIU_INT,&len[imdex]);
634:     source[imdex]  = recv_status.MPI_SOURCE;
635:     len[imdex]     = len[imdex]/2;
636:     /* count how many local owners for each of my global owned indices */
637:     for (i=0; i<len[imdex]; i++) nownedsenders[recvs[2*imdex*nmax+2*i]-rstart]++;
638:     cnt--;
639:   }
640:   PetscFree(recv_waits);

642:   /* count how many globally owned indices are on an edge multiplied by how many processors own them. */
643:   nowned  = 0;
644:   nownedm = 0;
645:   for (i=0; i<ng; i++) {
646:     if (nownedsenders[i] > 1) {nownedm += nownedsenders[i]; nowned++;}
647:   }

649:   /* create single array to contain rank of all local owners of each globally owned index */
650:   PetscMalloc((nownedm+1)*sizeof(PetscInt),&ownedsenders);
651:   PetscMalloc((ng+1)*sizeof(PetscInt),&starts);
652:   starts[0] = 0;
653:   for (i=1; i<ng; i++) {
654:     if (nownedsenders[i-1] > 1) starts[i] = starts[i-1] + nownedsenders[i-1];
655:     else starts[i] = starts[i-1];
656:   }

658:   /* for each nontrival globally owned node list all arriving processors */
659:   for (i=0; i<nrecvs; i++) {
660:     for (j=0; j<len[i]; j++) {
661:       node = recvs[2*i*nmax+2*j]-rstart;
662:       if (nownedsenders[node] > 1) {
663:         ownedsenders[starts[node]++] = source[i];
664:       }
665:     }
666:   }

668:   if (debug) { /* -----------------------------------  */
669:     starts[0]    = 0;
670:     for (i=1; i<ng; i++) {
671:       if (nownedsenders[i-1] > 1) starts[i] = starts[i-1] + nownedsenders[i-1];
672:       else starts[i] = starts[i-1];
673:     }
674:     for (i=0; i<ng; i++) {
675:       if (nownedsenders[i] > 1) {
676:         PetscSynchronizedPrintf(comm,"[%d] global node %d local owner processors: ",rank,i+rstart);
677:         for (j=0; j<nownedsenders[i]; j++) {
678:           PetscSynchronizedPrintf(comm,"%d ",ownedsenders[starts[i]+j]);
679:         }
680:         PetscSynchronizedPrintf(comm,"\n");
681:       }
682:     }
683:     PetscSynchronizedFlush(comm);
684:   }/* -----------------------------------  */

686:   /* wait on original sends */
687:   if (nsends) {
688:     PetscMalloc(nsends*sizeof(MPI_Status),&send_status);
689:     MPI_Waitall(nsends,send_waits,send_status);
690:     PetscFree(send_status);
691:   }
692:   PetscFree(send_waits);
693:   PetscFree(sends);
694:   PetscFree(nprocs);

696:   /* pack messages to send back to local owners */
697:   starts[0]    = 0;
698:   for (i=1; i<ng; i++) {
699:     if (nownedsenders[i-1] > 1) starts[i] = starts[i-1] + nownedsenders[i-1];
700:     else starts[i] = starts[i-1];
701:   }
702:   nsends2 = nrecvs;
703:   PetscMalloc((nsends2+1)*sizeof(PetscInt),&nprocs); /* length of each message */
704:   for (i=0; i<nrecvs; i++) {
705:     nprocs[i] = 1;
706:     for (j=0; j<len[i]; j++) {
707:       node = recvs[2*i*nmax+2*j]-rstart;
708:       if (nownedsenders[node] > 1) {
709:         nprocs[i] += 2 + nownedsenders[node];
710:       }
711:     }
712:   }
713:   nt = 0; for (i=0; i<nsends2; i++) nt += nprocs[i];
714:   PetscMalloc((nt+1)*sizeof(PetscInt),&sends2);
715:   PetscMalloc((nsends2+1)*sizeof(PetscInt),&starts2);
716:   starts2[0] = 0; for (i=1; i<nsends2; i++) starts2[i] = starts2[i-1] + nprocs[i-1];
717:   /*
718:      Each message is 1 + nprocs[i] long, and consists of 
719:        (0) the number of nodes being sent back 
720:        (1) the local node number,
721:        (2) the number of processors sharing it,
722:        (3) the processors sharing it
723:   */
724:   for (i=0; i<nsends2; i++) {
725:     cnt = 1;
726:     sends2[starts2[i]] = 0;
727:     for (j=0; j<len[i]; j++) {
728:       node = recvs[2*i*nmax+2*j]-rstart;
729:       if (nownedsenders[node] > 1) {
730:         sends2[starts2[i]]++;
731:         sends2[starts2[i]+cnt++] = recvs[2*i*nmax+2*j+1];
732:         sends2[starts2[i]+cnt++] = nownedsenders[node];
733:         PetscMemcpy(&sends2[starts2[i]+cnt],&ownedsenders[starts[node]],nownedsenders[node]*sizeof(PetscInt));
734:         cnt += nownedsenders[node];
735:       }
736:     }
737:   }

739:   /* receive the message lengths */
740:   nrecvs2 = nsends;
741:   PetscMalloc((nrecvs2+1)*sizeof(PetscInt),&lens2);
742:   PetscMalloc((nrecvs2+1)*sizeof(PetscInt),&starts3);
743:   PetscMalloc((nrecvs2+1)*sizeof(MPI_Request),&recv_waits);
744:   for (i=0; i<nrecvs2; i++) {
745:     MPI_Irecv(&lens2[i],1,MPIU_INT,dest[i],tag2,comm,recv_waits+i);
746:   }

748:   /* send the message lengths */
749:   for (i=0; i<nsends2; i++) {
750:     MPI_Send(&nprocs[i],1,MPIU_INT,source[i],tag2,comm);
751:   }

753:   /* wait on receives of lens */
754:   if (nrecvs2) {
755:     PetscMalloc(nrecvs2*sizeof(MPI_Status),&recv_statuses);
756:     MPI_Waitall(nrecvs2,recv_waits,recv_statuses);
757:     PetscFree(recv_statuses);
758:   }
759:   PetscFree(recv_waits);

761:   starts3[0] = 0;
762:   nt         = 0;
763:   for (i=0; i<nrecvs2-1; i++) {
764:     starts3[i+1] = starts3[i] + lens2[i];
765:     nt          += lens2[i];
766:   }
767:   nt += lens2[nrecvs2-1];

769:   PetscMalloc((nt+1)*sizeof(PetscInt),&recvs2);
770:   PetscMalloc((nrecvs2+1)*sizeof(MPI_Request),&recv_waits);
771:   for (i=0; i<nrecvs2; i++) {
772:     MPI_Irecv(recvs2+starts3[i],lens2[i],MPIU_INT,dest[i],tag3,comm,recv_waits+i);
773:   }
774: 
775:   /* send the messages */
776:   PetscMalloc((nsends2+1)*sizeof(MPI_Request),&send_waits);
777:   for (i=0; i<nsends2; i++) {
778:     MPI_Isend(sends2+starts2[i],nprocs[i],MPIU_INT,source[i],tag3,comm,send_waits+i);
779:   }

781:   /* wait on receives */
782:   if (nrecvs2) {
783:     PetscMalloc(nrecvs2*sizeof(MPI_Status),&recv_statuses);
784:     MPI_Waitall(nrecvs2,recv_waits,recv_statuses);
785:     PetscFree(recv_statuses);
786:   }
787:   PetscFree(recv_waits);
788:   PetscFree(nprocs);

790:   if (debug) { /* -----------------------------------  */
791:     cnt = 0;
792:     for (i=0; i<nrecvs2; i++) {
793:       nt = recvs2[cnt++];
794:       for (j=0; j<nt; j++) {
795:         PetscSynchronizedPrintf(comm,"[%d] local node %d number of subdomains %d: ",rank,recvs2[cnt],recvs2[cnt+1]);
796:         for (k=0; k<recvs2[cnt+1]; k++) {
797:           PetscSynchronizedPrintf(comm,"%d ",recvs2[cnt+2+k]);
798:         }
799:         cnt += 2 + recvs2[cnt+1];
800:         PetscSynchronizedPrintf(comm,"\n");
801:       }
802:     }
803:     PetscSynchronizedFlush(comm);
804:   } /* -----------------------------------  */

806:   /* count number subdomains for each local node */
807:   PetscMalloc(size*sizeof(PetscInt),&nprocs);
808:   PetscMemzero(nprocs,size*sizeof(PetscInt));
809:   cnt  = 0;
810:   for (i=0; i<nrecvs2; i++) {
811:     nt = recvs2[cnt++];
812:     for (j=0; j<nt; j++) {
813:       for (k=0; k<recvs2[cnt+1]; k++) {
814:         nprocs[recvs2[cnt+2+k]]++;
815:       }
816:       cnt += 2 + recvs2[cnt+1];
817:     }
818:   }
819:   nt = 0; for (i=0; i<size; i++) nt += (nprocs[i] > 0);
820:   *nproc    = nt;
821:   PetscMalloc((nt+1)*sizeof(PetscInt),procs);
822:   PetscMalloc((nt+1)*sizeof(PetscInt),numprocs);
823:   PetscMalloc((nt+1)*sizeof(PetscInt*),indices);
824:   PetscMalloc(size*sizeof(PetscInt),&bprocs);
825:   cnt       = 0;
826:   for (i=0; i<size; i++) {
827:     if (nprocs[i] > 0) {
828:       bprocs[i]        = cnt;
829:       (*procs)[cnt]    = i;
830:       (*numprocs)[cnt] = nprocs[i];
831:       PetscMalloc(nprocs[i]*sizeof(PetscInt),&(*indices)[cnt]);
832:       cnt++;
833:     }
834:   }

836:   /* make the list of subdomains for each nontrivial local node */
837:   PetscMemzero(*numprocs,nt*sizeof(PetscInt));
838:   cnt  = 0;
839:   for (i=0; i<nrecvs2; i++) {
840:     nt = recvs2[cnt++];
841:     for (j=0; j<nt; j++) {
842:       for (k=0; k<recvs2[cnt+1]; k++) {
843:         (*indices)[bprocs[recvs2[cnt+2+k]]][(*numprocs)[bprocs[recvs2[cnt+2+k]]]++] = recvs2[cnt];
844:       }
845:       cnt += 2 + recvs2[cnt+1];
846:     }
847:   }
848:   PetscFree(bprocs);
849:   PetscFree(recvs2);

851:   /* sort the node indexing by their global numbers */
852:   nt = *nproc;
853:   for (i=0; i<nt; i++) {
854:     PetscMalloc(((*numprocs)[i])*sizeof(PetscInt),&tmp);
855:     for (j=0; j<(*numprocs)[i]; j++) {
856:       tmp[j] = lindices[(*indices)[i][j]];
857:     }
858:     PetscSortIntWithArray((*numprocs)[i],tmp,(*indices)[i]);
859:     PetscFree(tmp);
860:   }

862:   if (debug) { /* -----------------------------------  */
863:     nt = *nproc;
864:     for (i=0; i<nt; i++) {
865:       PetscSynchronizedPrintf(comm,"[%d] subdomain %d number of indices %d: ",rank,(*procs)[i],(*numprocs)[i]);
866:       for (j=0; j<(*numprocs)[i]; j++) {
867:         PetscSynchronizedPrintf(comm,"%d ",(*indices)[i][j]);
868:       }
869:       PetscSynchronizedPrintf(comm,"\n");
870:     }
871:     PetscSynchronizedFlush(comm);
872:   } /* -----------------------------------  */

874:   /* wait on sends */
875:   if (nsends2) {
876:     PetscMalloc(nsends2*sizeof(MPI_Status),&send_status);
877:     MPI_Waitall(nsends2,send_waits,send_status);
878:     PetscFree(send_status);
879:   }

881:   PetscFree(starts3);
882:   PetscFree(dest);
883:   PetscFree(send_waits);

885:   PetscFree(nownedsenders);
886:   PetscFree(ownedsenders);
887:   PetscFree(starts);
888:   PetscFree(starts2);
889:   PetscFree(lens2);

891:   PetscFree(source);
892:   PetscFree(len);
893:   PetscFree(recvs);
894:   PetscFree(nprocs);
895:   PetscFree(sends2);

897:   /* put the information about myself as the first entry in the list */
898:   first_procs    = (*procs)[0];
899:   first_numprocs = (*numprocs)[0];
900:   first_indices  = (*indices)[0];
901:   for (i=0; i<*nproc; i++) {
902:     if ((*procs)[i] == rank) {
903:       (*procs)[0]    = (*procs)[i];
904:       (*numprocs)[0] = (*numprocs)[i];
905:       (*indices)[0]  = (*indices)[i];
906:       (*procs)[i]    = first_procs;
907:       (*numprocs)[i] = first_numprocs;
908:       (*indices)[i]  = first_indices;
909:       break;
910:     }
911:   }
912:   return(0);
913: }

917: /*@C
918:     ISLocalToGlobalMappingRestoreInfo - Frees the memory allocated by ISLocalToGlobalMappingGetInfo()

920:     Collective on ISLocalToGlobalMapping

922:     Input Parameters:
923: .   mapping - the mapping from local to global indexing

925:     Output Parameter:
926: +   nproc - number of processors that are connected to this one
927: .   proc - neighboring processors
928: .   numproc - number of indices for each processor
929: -   indices - indices of local nodes shared with neighbor (sorted by global numbering)

931:     Level: advanced

933: .seealso: ISLocalToGlobalMappingDestroy(), ISLocalToGlobalMappingCreateIS(), ISLocalToGlobalMappingCreate(),
934:           ISLocalToGlobalMappingGetInfo()
935: @*/
936: PetscErrorCode PETSCVEC_DLLEXPORT ISLocalToGlobalMappingRestoreInfo(ISLocalToGlobalMapping mapping,PetscInt *nproc,PetscInt *procs[],PetscInt *numprocs[],PetscInt **indices[])
937: {
939:   PetscInt i;

942:   PetscFree(*procs);
943:   PetscFree(*numprocs);
944:   if (*indices) {
945:     PetscFree((*indices)[0]);
946:     for (i=1; i<*nproc; i++) {
947:       PetscFree((*indices)[i]);
948:     }
949:     PetscFree(*indices);
950:   }
951:   return(0);
952: }