Actual source code: matstash.c

petsc-3.10.5 2019-03-28
Report Typos and Errors

  2:  #include <petsc/private/matimpl.h>

  4: #define DEFAULT_STASH_SIZE   10000

  6: static PetscErrorCode MatStashScatterBegin_Ref(Mat,MatStash*,PetscInt*);
  7: static PetscErrorCode MatStashScatterGetMesg_Ref(MatStash*,PetscMPIInt*,PetscInt**,PetscInt**,PetscScalar**,PetscInt*);
  8: static PetscErrorCode MatStashScatterEnd_Ref(MatStash*);
  9: #if !defined(PETSC_HAVE_MPIUNI)
 10: static PetscErrorCode MatStashScatterBegin_BTS(Mat,MatStash*,PetscInt*);
 11: static PetscErrorCode MatStashScatterGetMesg_BTS(MatStash*,PetscMPIInt*,PetscInt**,PetscInt**,PetscScalar**,PetscInt*);
 12: static PetscErrorCode MatStashScatterEnd_BTS(MatStash*);
 13: static PetscErrorCode MatStashScatterDestroy_BTS(MatStash*);
 14: #endif

 16: /*
 17:   MatStashCreate_Private - Creates a stash,currently used for all the parallel
 18:   matrix implementations. The stash is where elements of a matrix destined
 19:   to be stored on other processors are kept until matrix assembly is done.

 21:   This is a simple minded stash. Simply adds entries to end of stash.

 23:   Input Parameters:
 24:   comm - communicator, required for scatters.
 25:   bs   - stash block size. used when stashing blocks of values

 27:   Output Parameters:
 28:   stash    - the newly created stash
 29: */
 30: PetscErrorCode MatStashCreate_Private(MPI_Comm comm,PetscInt bs,MatStash *stash)
 31: {
 33:   PetscInt       max,*opt,nopt,i;
 34:   PetscBool      flg;

 37:   /* Require 2 tags,get the second using PetscCommGetNewTag() */
 38:   stash->comm = comm;

 40:   PetscCommGetNewTag(stash->comm,&stash->tag1);
 41:   PetscCommGetNewTag(stash->comm,&stash->tag2);
 42:   MPI_Comm_size(stash->comm,&stash->size);
 43:   MPI_Comm_rank(stash->comm,&stash->rank);
 44:   PetscMalloc1(2*stash->size,&stash->flg_v);
 45:   for (i=0; i<2*stash->size; i++) stash->flg_v[i] = -1;


 48:   nopt = stash->size;
 49:   PetscMalloc1(nopt,&opt);
 50:   PetscOptionsGetIntArray(NULL,NULL,"-matstash_initial_size",opt,&nopt,&flg);
 51:   if (flg) {
 52:     if (nopt == 1)                max = opt[0];
 53:     else if (nopt == stash->size) max = opt[stash->rank];
 54:     else if (stash->rank < nopt)  max = opt[stash->rank];
 55:     else                          max = 0; /* Use default */
 56:     stash->umax = max;
 57:   } else {
 58:     stash->umax = 0;
 59:   }
 60:   PetscFree(opt);
 61:   if (bs <= 0) bs = 1;

 63:   stash->bs         = bs;
 64:   stash->nmax       = 0;
 65:   stash->oldnmax    = 0;
 66:   stash->n          = 0;
 67:   stash->reallocs   = -1;
 68:   stash->space_head = 0;
 69:   stash->space      = 0;

 71:   stash->send_waits  = 0;
 72:   stash->recv_waits  = 0;
 73:   stash->send_status = 0;
 74:   stash->nsends      = 0;
 75:   stash->nrecvs      = 0;
 76:   stash->svalues     = 0;
 77:   stash->rvalues     = 0;
 78:   stash->rindices    = 0;
 79:   stash->nprocessed  = 0;
 80:   stash->reproduce   = PETSC_FALSE;
 81:   stash->blocktype   = MPI_DATATYPE_NULL;

 83:   PetscOptionsGetBool(NULL,NULL,"-matstash_reproduce",&stash->reproduce,NULL);
 84: #if !defined(PETSC_HAVE_MPIUNI)
 85:   PetscOptionsGetBool(NULL,NULL,"-matstash_legacy",&flg,NULL);
 86:   if (!flg) {
 87:     stash->ScatterBegin   = MatStashScatterBegin_BTS;
 88:     stash->ScatterGetMesg = MatStashScatterGetMesg_BTS;
 89:     stash->ScatterEnd     = MatStashScatterEnd_BTS;
 90:     stash->ScatterDestroy = MatStashScatterDestroy_BTS;
 91:   } else {
 92: #endif
 93:     stash->ScatterBegin   = MatStashScatterBegin_Ref;
 94:     stash->ScatterGetMesg = MatStashScatterGetMesg_Ref;
 95:     stash->ScatterEnd     = MatStashScatterEnd_Ref;
 96:     stash->ScatterDestroy = NULL;
 97: #if !defined(PETSC_HAVE_MPIUNI)
 98:   }
 99: #endif
100:   return(0);
101: }

103: /*
104:    MatStashDestroy_Private - Destroy the stash
105: */
106: PetscErrorCode MatStashDestroy_Private(MatStash *stash)
107: {

111:   PetscMatStashSpaceDestroy(&stash->space_head);
112:   if (stash->ScatterDestroy) {(*stash->ScatterDestroy)(stash);}

114:   stash->space = 0;

116:   PetscFree(stash->flg_v);
117:   return(0);
118: }

120: /*
121:    MatStashScatterEnd_Private - This is called as the final stage of
122:    scatter. The final stages of message passing is done here, and
123:    all the memory used for message passing is cleaned up. This
124:    routine also resets the stash, and deallocates the memory used
125:    for the stash. It also keeps track of the current memory usage
126:    so that the same value can be used the next time through.
127: */
128: PetscErrorCode MatStashScatterEnd_Private(MatStash *stash)
129: {

133:   (*stash->ScatterEnd)(stash);
134:   return(0);
135: }

137: static PetscErrorCode MatStashScatterEnd_Ref(MatStash *stash)
138: {
140:   PetscInt       nsends=stash->nsends,bs2,oldnmax,i;
141:   MPI_Status     *send_status;

144:   for (i=0; i<2*stash->size; i++) stash->flg_v[i] = -1;
145:   /* wait on sends */
146:   if (nsends) {
147:     PetscMalloc1(2*nsends,&send_status);
148:     MPI_Waitall(2*nsends,stash->send_waits,send_status);
149:     PetscFree(send_status);
150:   }

152:   /* Now update nmaxold to be app 10% more than max n used, this way the
153:      wastage of space is reduced the next time this stash is used.
154:      Also update the oldmax, only if it increases */
155:   if (stash->n) {
156:     bs2     = stash->bs*stash->bs;
157:     oldnmax = ((int)(stash->n * 1.1) + 5)*bs2;
158:     if (oldnmax > stash->oldnmax) stash->oldnmax = oldnmax;
159:   }

161:   stash->nmax       = 0;
162:   stash->n          = 0;
163:   stash->reallocs   = -1;
164:   stash->nprocessed = 0;

166:   PetscMatStashSpaceDestroy(&stash->space_head);

168:   stash->space = 0;

170:   PetscFree(stash->send_waits);
171:   PetscFree(stash->recv_waits);
172:   PetscFree2(stash->svalues,stash->sindices);
173:   PetscFree(stash->rvalues[0]);
174:   PetscFree(stash->rvalues);
175:   PetscFree(stash->rindices[0]);
176:   PetscFree(stash->rindices);
177:   return(0);
178: }

180: /*
181:    MatStashGetInfo_Private - Gets the relavant statistics of the stash

183:    Input Parameters:
184:    stash    - the stash
185:    nstash   - the size of the stash. Indicates the number of values stored.
186:    reallocs - the number of additional mallocs incurred.

188: */
189: PetscErrorCode MatStashGetInfo_Private(MatStash *stash,PetscInt *nstash,PetscInt *reallocs)
190: {
191:   PetscInt bs2 = stash->bs*stash->bs;

194:   if (nstash) *nstash = stash->n*bs2;
195:   if (reallocs) {
196:     if (stash->reallocs < 0) *reallocs = 0;
197:     else                     *reallocs = stash->reallocs;
198:   }
199:   return(0);
200: }

202: /*
203:    MatStashSetInitialSize_Private - Sets the initial size of the stash

205:    Input Parameters:
206:    stash  - the stash
207:    max    - the value that is used as the max size of the stash.
208:             this value is used while allocating memory.
209: */
210: PetscErrorCode MatStashSetInitialSize_Private(MatStash *stash,PetscInt max)
211: {
213:   stash->umax = max;
214:   return(0);
215: }

217: /* MatStashExpand_Private - Expand the stash. This function is called
218:    when the space in the stash is not sufficient to add the new values
219:    being inserted into the stash.

221:    Input Parameters:
222:    stash - the stash
223:    incr  - the minimum increase requested

225:    Notes:
226:    This routine doubles the currently used memory.
227:  */
228: static PetscErrorCode MatStashExpand_Private(MatStash *stash,PetscInt incr)
229: {
231:   PetscInt       newnmax,bs2= stash->bs*stash->bs;

234:   /* allocate a larger stash */
235:   if (!stash->oldnmax && !stash->nmax) { /* new stash */
236:     if (stash->umax)                  newnmax = stash->umax/bs2;
237:     else                              newnmax = DEFAULT_STASH_SIZE/bs2;
238:   } else if (!stash->nmax) { /* resuing stash */
239:     if (stash->umax > stash->oldnmax) newnmax = stash->umax/bs2;
240:     else                              newnmax = stash->oldnmax/bs2;
241:   } else                              newnmax = stash->nmax*2;
242:   if (newnmax  < (stash->nmax + incr)) newnmax += 2*incr;

244:   /* Get a MatStashSpace and attach it to stash */
245:   PetscMatStashSpaceGet(bs2,newnmax,&stash->space);
246:   if (!stash->space_head) { /* new stash or resuing stash->oldnmax */
247:     stash->space_head = stash->space;
248:   }

250:   stash->reallocs++;
251:   stash->nmax = newnmax;
252:   return(0);
253: }
254: /*
255:   MatStashValuesRow_Private - inserts values into the stash. This function
256:   expects the values to be roworiented. Multiple columns belong to the same row
257:   can be inserted with a single call to this function.

259:   Input Parameters:
260:   stash  - the stash
261:   row    - the global row correspoiding to the values
262:   n      - the number of elements inserted. All elements belong to the above row.
263:   idxn   - the global column indices corresponding to each of the values.
264:   values - the values inserted
265: */
266: PetscErrorCode MatStashValuesRow_Private(MatStash *stash,PetscInt row,PetscInt n,const PetscInt idxn[],const PetscScalar values[],PetscBool ignorezeroentries)
267: {
268:   PetscErrorCode     ierr;
269:   PetscInt           i,k,cnt = 0;
270:   PetscMatStashSpace space=stash->space;

273:   /* Check and see if we have sufficient memory */
274:   if (!space || space->local_remaining < n) {
275:     MatStashExpand_Private(stash,n);
276:   }
277:   space = stash->space;
278:   k     = space->local_used;
279:   for (i=0; i<n; i++) {
280:     if (ignorezeroentries && (values[i] == 0.0)) continue;
281:     space->idx[k] = row;
282:     space->idy[k] = idxn[i];
283:     space->val[k] = values[i];
284:     k++;
285:     cnt++;
286:   }
287:   stash->n               += cnt;
288:   space->local_used      += cnt;
289:   space->local_remaining -= cnt;
290:   return(0);
291: }

293: /*
294:   MatStashValuesCol_Private - inserts values into the stash. This function
295:   expects the values to be columnoriented. Multiple columns belong to the same row
296:   can be inserted with a single call to this function.

298:   Input Parameters:
299:   stash   - the stash
300:   row     - the global row correspoiding to the values
301:   n       - the number of elements inserted. All elements belong to the above row.
302:   idxn    - the global column indices corresponding to each of the values.
303:   values  - the values inserted
304:   stepval - the consecutive values are sepated by a distance of stepval.
305:             this happens because the input is columnoriented.
306: */
307: PetscErrorCode MatStashValuesCol_Private(MatStash *stash,PetscInt row,PetscInt n,const PetscInt idxn[],const PetscScalar values[],PetscInt stepval,PetscBool ignorezeroentries)
308: {
309:   PetscErrorCode     ierr;
310:   PetscInt           i,k,cnt = 0;
311:   PetscMatStashSpace space=stash->space;

314:   /* Check and see if we have sufficient memory */
315:   if (!space || space->local_remaining < n) {
316:     MatStashExpand_Private(stash,n);
317:   }
318:   space = stash->space;
319:   k     = space->local_used;
320:   for (i=0; i<n; i++) {
321:     if (ignorezeroentries && (values[i*stepval] == 0.0)) continue;
322:     space->idx[k] = row;
323:     space->idy[k] = idxn[i];
324:     space->val[k] = values[i*stepval];
325:     k++;
326:     cnt++;
327:   }
328:   stash->n               += cnt;
329:   space->local_used      += cnt;
330:   space->local_remaining -= cnt;
331:   return(0);
332: }

334: /*
335:   MatStashValuesRowBlocked_Private - inserts blocks of values into the stash.
336:   This function expects the values to be roworiented. Multiple columns belong
337:   to the same block-row can be inserted with a single call to this function.
338:   This function extracts the sub-block of values based on the dimensions of
339:   the original input block, and the row,col values corresponding to the blocks.

341:   Input Parameters:
342:   stash  - the stash
343:   row    - the global block-row correspoiding to the values
344:   n      - the number of elements inserted. All elements belong to the above row.
345:   idxn   - the global block-column indices corresponding to each of the blocks of
346:            values. Each block is of size bs*bs.
347:   values - the values inserted
348:   rmax   - the number of block-rows in the original block.
349:   cmax   - the number of block-columsn on the original block.
350:   idx    - the index of the current block-row in the original block.
351: */
352: PetscErrorCode MatStashValuesRowBlocked_Private(MatStash *stash,PetscInt row,PetscInt n,const PetscInt idxn[],const PetscScalar values[],PetscInt rmax,PetscInt cmax,PetscInt idx)
353: {
354:   PetscErrorCode     ierr;
355:   PetscInt           i,j,k,bs2,bs=stash->bs,l;
356:   const PetscScalar  *vals;
357:   PetscScalar        *array;
358:   PetscMatStashSpace space=stash->space;

361:   if (!space || space->local_remaining < n) {
362:     MatStashExpand_Private(stash,n);
363:   }
364:   space = stash->space;
365:   l     = space->local_used;
366:   bs2   = bs*bs;
367:   for (i=0; i<n; i++) {
368:     space->idx[l] = row;
369:     space->idy[l] = idxn[i];
370:     /* Now copy over the block of values. Store the values column oriented.
371:        This enables inserting multiple blocks belonging to a row with a single
372:        funtion call */
373:     array = space->val + bs2*l;
374:     vals  = values + idx*bs2*n + bs*i;
375:     for (j=0; j<bs; j++) {
376:       for (k=0; k<bs; k++) array[k*bs] = vals[k];
377:       array++;
378:       vals += cmax*bs;
379:     }
380:     l++;
381:   }
382:   stash->n               += n;
383:   space->local_used      += n;
384:   space->local_remaining -= n;
385:   return(0);
386: }

388: /*
389:   MatStashValuesColBlocked_Private - inserts blocks of values into the stash.
390:   This function expects the values to be roworiented. Multiple columns belong
391:   to the same block-row can be inserted with a single call to this function.
392:   This function extracts the sub-block of values based on the dimensions of
393:   the original input block, and the row,col values corresponding to the blocks.

395:   Input Parameters:
396:   stash  - the stash
397:   row    - the global block-row correspoiding to the values
398:   n      - the number of elements inserted. All elements belong to the above row.
399:   idxn   - the global block-column indices corresponding to each of the blocks of
400:            values. Each block is of size bs*bs.
401:   values - the values inserted
402:   rmax   - the number of block-rows in the original block.
403:   cmax   - the number of block-columsn on the original block.
404:   idx    - the index of the current block-row in the original block.
405: */
406: PetscErrorCode MatStashValuesColBlocked_Private(MatStash *stash,PetscInt row,PetscInt n,const PetscInt idxn[],const PetscScalar values[],PetscInt rmax,PetscInt cmax,PetscInt idx)
407: {
408:   PetscErrorCode     ierr;
409:   PetscInt           i,j,k,bs2,bs=stash->bs,l;
410:   const PetscScalar  *vals;
411:   PetscScalar        *array;
412:   PetscMatStashSpace space=stash->space;

415:   if (!space || space->local_remaining < n) {
416:     MatStashExpand_Private(stash,n);
417:   }
418:   space = stash->space;
419:   l     = space->local_used;
420:   bs2   = bs*bs;
421:   for (i=0; i<n; i++) {
422:     space->idx[l] = row;
423:     space->idy[l] = idxn[i];
424:     /* Now copy over the block of values. Store the values column oriented.
425:      This enables inserting multiple blocks belonging to a row with a single
426:      funtion call */
427:     array = space->val + bs2*l;
428:     vals  = values + idx*bs2*n + bs*i;
429:     for (j=0; j<bs; j++) {
430:       for (k=0; k<bs; k++) array[k] = vals[k];
431:       array += bs;
432:       vals  += rmax*bs;
433:     }
434:     l++;
435:   }
436:   stash->n               += n;
437:   space->local_used      += n;
438:   space->local_remaining -= n;
439:   return(0);
440: }
441: /*
442:   MatStashScatterBegin_Private - Initiates the transfer of values to the
443:   correct owners. This function goes through the stash, and check the
444:   owners of each stashed value, and sends the values off to the owner
445:   processors.

447:   Input Parameters:
448:   stash  - the stash
449:   owners - an array of size 'no-of-procs' which gives the ownership range
450:            for each node.

452:   Notes:
453:     The 'owners' array in the cased of the blocked-stash has the
454:   ranges specified blocked global indices, and for the regular stash in
455:   the proper global indices.
456: */
457: PetscErrorCode MatStashScatterBegin_Private(Mat mat,MatStash *stash,PetscInt *owners)
458: {

462:   (*stash->ScatterBegin)(mat,stash,owners);
463:   return(0);
464: }

466: static PetscErrorCode MatStashScatterBegin_Ref(Mat mat,MatStash *stash,PetscInt *owners)
467: {
468:   PetscInt           *owner,*startv,*starti,tag1=stash->tag1,tag2=stash->tag2,bs2;
469:   PetscInt           size=stash->size,nsends;
470:   PetscErrorCode     ierr;
471:   PetscInt           count,*sindices,**rindices,i,j,idx,lastidx,l;
472:   PetscScalar        **rvalues,*svalues;
473:   MPI_Comm           comm = stash->comm;
474:   MPI_Request        *send_waits,*recv_waits,*recv_waits1,*recv_waits2;
475:   PetscMPIInt        *sizes,*nlengths,nreceives;
476:   PetscInt           *sp_idx,*sp_idy;
477:   PetscScalar        *sp_val;
478:   PetscMatStashSpace space,space_next;

481:   {                             /* make sure all processors are either in INSERTMODE or ADDMODE */
482:     InsertMode addv;
483:     MPIU_Allreduce((PetscEnum*)&mat->insertmode,(PetscEnum*)&addv,1,MPIU_ENUM,MPI_BOR,PetscObjectComm((PetscObject)mat));
484:     if (addv == (ADD_VALUES|INSERT_VALUES)) SETERRQ(PetscObjectComm((PetscObject)mat),PETSC_ERR_ARG_WRONGSTATE,"Some processors inserted others added");
485:     mat->insertmode = addv; /* in case this processor had no cache */
486:   }

488:   bs2 = stash->bs*stash->bs;

490:   /*  first count number of contributors to each processor */
491:   PetscCalloc1(size,&sizes);
492:   PetscCalloc1(size,&nlengths);
493:   PetscMalloc1(stash->n+1,&owner);

495:   i       = j    = 0;
496:   lastidx = -1;
497:   space   = stash->space_head;
498:   while (space) {
499:     space_next = space->next;
500:     sp_idx     = space->idx;
501:     for (l=0; l<space->local_used; l++) {
502:       /* if indices are NOT locally sorted, need to start search at the beginning */
503:       if (lastidx > (idx = sp_idx[l])) j = 0;
504:       lastidx = idx;
505:       for (; j<size; j++) {
506:         if (idx >= owners[j] && idx < owners[j+1]) {
507:           nlengths[j]++; owner[i] = j; break;
508:         }
509:       }
510:       i++;
511:     }
512:     space = space_next;
513:   }
514:   /* Now check what procs get messages - and compute nsends. */
515:   for (i=0, nsends=0; i<size; i++) {
516:     if (nlengths[i]) {
517:       sizes[i] = 1; nsends++;
518:     }
519:   }

521:   {PetscMPIInt *onodes,*olengths;
522:    /* Determine the number of messages to expect, their lengths, from from-ids */
523:    PetscGatherNumberOfMessages(comm,sizes,nlengths,&nreceives);
524:    PetscGatherMessageLengths(comm,nsends,nreceives,nlengths,&onodes,&olengths);
525:    /* since clubbing row,col - lengths are multiplied by 2 */
526:    for (i=0; i<nreceives; i++) olengths[i] *=2;
527:    PetscPostIrecvInt(comm,tag1,nreceives,onodes,olengths,&rindices,&recv_waits1);
528:    /* values are size 'bs2' lengths (and remove earlier factor 2 */
529:    for (i=0; i<nreceives; i++) olengths[i] = olengths[i]*bs2/2;
530:    PetscPostIrecvScalar(comm,tag2,nreceives,onodes,olengths,&rvalues,&recv_waits2);
531:    PetscFree(onodes);
532:    PetscFree(olengths);}

534:   /* do sends:
535:       1) starts[i] gives the starting index in svalues for stuff going to
536:          the ith processor
537:   */
538:   PetscMalloc2(bs2*stash->n,&svalues,2*(stash->n+1),&sindices);
539:   PetscMalloc1(2*nsends,&send_waits);
540:   PetscMalloc2(size,&startv,size,&starti);
541:   /* use 2 sends the first with all_a, the next with all_i and all_j */
542:   startv[0] = 0; starti[0] = 0;
543:   for (i=1; i<size; i++) {
544:     startv[i] = startv[i-1] + nlengths[i-1];
545:     starti[i] = starti[i-1] + 2*nlengths[i-1];
546:   }

548:   i     = 0;
549:   space = stash->space_head;
550:   while (space) {
551:     space_next = space->next;
552:     sp_idx     = space->idx;
553:     sp_idy     = space->idy;
554:     sp_val     = space->val;
555:     for (l=0; l<space->local_used; l++) {
556:       j = owner[i];
557:       if (bs2 == 1) {
558:         svalues[startv[j]] = sp_val[l];
559:       } else {
560:         PetscInt    k;
561:         PetscScalar *buf1,*buf2;
562:         buf1 = svalues+bs2*startv[j];
563:         buf2 = space->val + bs2*l;
564:         for (k=0; k<bs2; k++) buf1[k] = buf2[k];
565:       }
566:       sindices[starti[j]]             = sp_idx[l];
567:       sindices[starti[j]+nlengths[j]] = sp_idy[l];
568:       startv[j]++;
569:       starti[j]++;
570:       i++;
571:     }
572:     space = space_next;
573:   }
574:   startv[0] = 0;
575:   for (i=1; i<size; i++) startv[i] = startv[i-1] + nlengths[i-1];

577:   for (i=0,count=0; i<size; i++) {
578:     if (sizes[i]) {
579:       MPI_Isend(sindices+2*startv[i],2*nlengths[i],MPIU_INT,i,tag1,comm,send_waits+count++);
580:       MPI_Isend(svalues+bs2*startv[i],bs2*nlengths[i],MPIU_SCALAR,i,tag2,comm,send_waits+count++);
581:     }
582:   }
583: #if defined(PETSC_USE_INFO)
584:   PetscInfo1(NULL,"No of messages: %d \n",nsends);
585:   for (i=0; i<size; i++) {
586:     if (sizes[i]) {
587:       PetscInfo2(NULL,"Mesg_to: %d: size: %d bytes\n",i,nlengths[i]*(bs2*sizeof(PetscScalar)+2*sizeof(PetscInt)));
588:     }
589:   }
590: #endif
591:   PetscFree(nlengths);
592:   PetscFree(owner);
593:   PetscFree2(startv,starti);
594:   PetscFree(sizes);

596:   /* recv_waits need to be contiguous for MatStashScatterGetMesg_Private() */
597:   PetscMalloc1(2*nreceives,&recv_waits);

599:   for (i=0; i<nreceives; i++) {
600:     recv_waits[2*i]   = recv_waits1[i];
601:     recv_waits[2*i+1] = recv_waits2[i];
602:   }
603:   stash->recv_waits = recv_waits;

605:   PetscFree(recv_waits1);
606:   PetscFree(recv_waits2);

608:   stash->svalues         = svalues;
609:   stash->sindices        = sindices;
610:   stash->rvalues         = rvalues;
611:   stash->rindices        = rindices;
612:   stash->send_waits      = send_waits;
613:   stash->nsends          = nsends;
614:   stash->nrecvs          = nreceives;
615:   stash->reproduce_count = 0;
616:   return(0);
617: }

619: /*
620:    MatStashScatterGetMesg_Private - This function waits on the receives posted
621:    in the function MatStashScatterBegin_Private() and returns one message at
622:    a time to the calling function. If no messages are left, it indicates this
623:    by setting flg = 0, else it sets flg = 1.

625:    Input Parameters:
626:    stash - the stash

628:    Output Parameters:
629:    nvals - the number of entries in the current message.
630:    rows  - an array of row indices (or blocked indices) corresponding to the values
631:    cols  - an array of columnindices (or blocked indices) corresponding to the values
632:    vals  - the values
633:    flg   - 0 indicates no more message left, and the current call has no values associated.
634:            1 indicates that the current call successfully received a message, and the
635:              other output parameters nvals,rows,cols,vals are set appropriately.
636: */
637: PetscErrorCode MatStashScatterGetMesg_Private(MatStash *stash,PetscMPIInt *nvals,PetscInt **rows,PetscInt **cols,PetscScalar **vals,PetscInt *flg)
638: {

642:   (*stash->ScatterGetMesg)(stash,nvals,rows,cols,vals,flg);
643:   return(0);
644: }

646: static PetscErrorCode MatStashScatterGetMesg_Ref(MatStash *stash,PetscMPIInt *nvals,PetscInt **rows,PetscInt **cols,PetscScalar **vals,PetscInt *flg)
647: {
649:   PetscMPIInt    i,*flg_v = stash->flg_v,i1,i2;
650:   PetscInt       bs2;
651:   MPI_Status     recv_status;
652:   PetscBool      match_found = PETSC_FALSE;

655:   *flg = 0; /* When a message is discovered this is reset to 1 */
656:   /* Return if no more messages to process */
657:   if (stash->nprocessed == stash->nrecvs) return(0);

659:   bs2 = stash->bs*stash->bs;
660:   /* If a matching pair of receives are found, process them, and return the data to
661:      the calling function. Until then keep receiving messages */
662:   while (!match_found) {
663:     if (stash->reproduce) {
664:       i    = stash->reproduce_count++;
665:       MPI_Wait(stash->recv_waits+i,&recv_status);
666:     } else {
667:       MPI_Waitany(2*stash->nrecvs,stash->recv_waits,&i,&recv_status);
668:     }
669:     if (recv_status.MPI_SOURCE < 0) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_PLIB,"Negative MPI source!");

671:     /* Now pack the received message into a structure which is usable by others */
672:     if (i % 2) {
673:       MPI_Get_count(&recv_status,MPIU_SCALAR,nvals);

675:       flg_v[2*recv_status.MPI_SOURCE] = i/2;

677:       *nvals = *nvals/bs2;
678:     } else {
679:       MPI_Get_count(&recv_status,MPIU_INT,nvals);

681:       flg_v[2*recv_status.MPI_SOURCE+1] = i/2;

683:       *nvals = *nvals/2; /* This message has both row indices and col indices */
684:     }

686:     /* Check if we have both messages from this proc */
687:     i1 = flg_v[2*recv_status.MPI_SOURCE];
688:     i2 = flg_v[2*recv_status.MPI_SOURCE+1];
689:     if (i1 != -1 && i2 != -1) {
690:       *rows = stash->rindices[i2];
691:       *cols = *rows + *nvals;
692:       *vals = stash->rvalues[i1];
693:       *flg  = 1;
694:       stash->nprocessed++;
695:       match_found = PETSC_TRUE;
696:     }
697:   }
698:   return(0);
699: }

701: #if !defined(PETSC_HAVE_MPIUNI)
702: typedef struct {
703:   PetscInt row;
704:   PetscInt col;
705:   PetscScalar vals[1];          /* Actually an array of length bs2 */
706: } MatStashBlock;

708: static PetscErrorCode MatStashSortCompress_Private(MatStash *stash,InsertMode insertmode)
709: {
711:   PetscMatStashSpace space;
712:   PetscInt n = stash->n,bs = stash->bs,bs2 = bs*bs,cnt,*row,*col,*perm,rowstart,i;
713:   PetscScalar **valptr;

716:   PetscMalloc4(n,&row,n,&col,n,&valptr,n,&perm);
717:   for (space=stash->space_head,cnt=0; space; space=space->next) {
718:     for (i=0; i<space->local_used; i++) {
719:       row[cnt] = space->idx[i];
720:       col[cnt] = space->idy[i];
721:       valptr[cnt] = &space->val[i*bs2];
722:       perm[cnt] = cnt;          /* Will tell us where to find valptr after sorting row[] and col[] */
723:       cnt++;
724:     }
725:   }
726:   if (cnt != n) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_PLIB,"MatStash n %D, but counted %D entries",n,cnt);
727:   PetscSortIntWithArrayPair(n,row,col,perm);
728:   /* Scan through the rows, sorting each one, combining duplicates, and packing send buffers */
729:   for (rowstart=0,cnt=0,i=1; i<=n; i++) {
730:     if (i == n || row[i] != row[rowstart]) {         /* Sort the last row. */
731:       PetscInt colstart;
732:       PetscSortIntWithArray(i-rowstart,&col[rowstart],&perm[rowstart]);
733:       for (colstart=rowstart; colstart<i; ) { /* Compress multiple insertions to the same location */
734:         PetscInt j,l;
735:         MatStashBlock *block;
736:         PetscSegBufferGet(stash->segsendblocks,1,&block);
737:         block->row = row[rowstart];
738:         block->col = col[colstart];
739:         PetscMemcpy(block->vals,valptr[perm[colstart]],bs2*sizeof(block->vals[0]));
740:         for (j=colstart+1; j<i && col[j] == col[colstart]; j++) { /* Add any extra stashed blocks at the same (row,col) */
741:           if (insertmode == ADD_VALUES) {
742:             for (l=0; l<bs2; l++) block->vals[l] += valptr[perm[j]][l];
743:           } else {
744:             PetscMemcpy(block->vals,valptr[perm[j]],bs2*sizeof(block->vals[0]));
745:           }
746:         }
747:         colstart = j;
748:       }
749:       rowstart = i;
750:     }
751:   }
752:   PetscFree4(row,col,valptr,perm);
753:   return(0);
754: }

756: static PetscErrorCode MatStashBlockTypeSetUp(MatStash *stash)
757: {

761:   if (stash->blocktype == MPI_DATATYPE_NULL) {
762:     PetscInt     bs2 = PetscSqr(stash->bs);
763:     PetscMPIInt  blocklens[2];
764:     MPI_Aint     displs[2];
765:     MPI_Datatype types[2],stype;
766:     /* C++ std::complex is not my favorite datatype.  Since it is not POD, we cannot use offsetof to find the offset of
767:      * vals.  But the layout is actually guaranteed by the standard, so we do a little dance here with struct
768:      * DummyBlock, substituting PetscReal for PetscComplex so that we can determine the offset.
769:      */
770:     struct DummyBlock {PetscInt row,col; PetscReal vals;};

772:     stash->blocktype_size = offsetof(struct DummyBlock,vals) + bs2*sizeof(PetscScalar);
773:     if (stash->blocktype_size % sizeof(PetscInt)) { /* Implies that PetscInt is larger and does not satisfy alignment without padding */
774:       stash->blocktype_size += sizeof(PetscInt) - stash->blocktype_size % sizeof(PetscInt);
775:     }
776:     PetscSegBufferCreate(stash->blocktype_size,1,&stash->segsendblocks);
777:     PetscSegBufferCreate(stash->blocktype_size,1,&stash->segrecvblocks);
778:     PetscSegBufferCreate(sizeof(MatStashFrame),1,&stash->segrecvframe);
779:     blocklens[0] = 2;
780:     blocklens[1] = bs2;
781:     displs[0] = offsetof(struct DummyBlock,row);
782:     displs[1] = offsetof(struct DummyBlock,vals);
783:     types[0] = MPIU_INT;
784:     types[1] = MPIU_SCALAR;
785:     MPI_Type_create_struct(2,blocklens,displs,types,&stype);
786:     MPI_Type_commit(&stype);
787:     MPI_Type_create_resized(stype,0,stash->blocktype_size,&stash->blocktype); /* MPI-2 */
788:     MPI_Type_commit(&stash->blocktype);
789:     MPI_Type_free(&stype);
790:   }
791:   return(0);
792: }

794: /* Callback invoked after target rank has initiatied receive of rendezvous message.
795:  * Here we post the main sends.
796:  */
797: static PetscErrorCode MatStashBTSSend_Private(MPI_Comm comm,const PetscMPIInt tag[],PetscMPIInt rankid,PetscMPIInt rank,void *sdata,MPI_Request req[],void *ctx)
798: {
799:   MatStash *stash = (MatStash*)ctx;
800:   MatStashHeader *hdr = (MatStashHeader*)sdata;

804:   if (rank != stash->sendranks[rankid]) SETERRQ3(comm,PETSC_ERR_PLIB,"BTS Send rank %d does not match sendranks[%d] %d",rank,rankid,stash->sendranks[rankid]);
805:   MPI_Isend(stash->sendframes[rankid].buffer,hdr->count,stash->blocktype,rank,tag[0],comm,&req[0]);
806:   stash->sendframes[rankid].count = hdr->count;
807:   stash->sendframes[rankid].pending = 1;
808:   return(0);
809: }

811: /* Callback invoked by target after receiving rendezvous message.
812:  * Here we post the main recvs.
813:  */
814: static PetscErrorCode MatStashBTSRecv_Private(MPI_Comm comm,const PetscMPIInt tag[],PetscMPIInt rank,void *rdata,MPI_Request req[],void *ctx)
815: {
816:   MatStash *stash = (MatStash*)ctx;
817:   MatStashHeader *hdr = (MatStashHeader*)rdata;
818:   MatStashFrame *frame;

822:   PetscSegBufferGet(stash->segrecvframe,1,&frame);
823:   PetscSegBufferGet(stash->segrecvblocks,hdr->count,&frame->buffer);
824:   MPI_Irecv(frame->buffer,hdr->count,stash->blocktype,rank,tag[0],comm,&req[0]);
825:   frame->count = hdr->count;
826:   frame->pending = 1;
827:   return(0);
828: }

830: /*
831:  * owners[] contains the ownership ranges; may be indexed by either blocks or scalars
832:  */
833: static PetscErrorCode MatStashScatterBegin_BTS(Mat mat,MatStash *stash,PetscInt owners[])
834: {
836:   size_t nblocks;
837:   char *sendblocks;

840: #if defined(PETSC_USE_DEBUG)
841:   {                             /* make sure all processors are either in INSERTMODE or ADDMODE */
842:     InsertMode addv;
843:     MPIU_Allreduce((PetscEnum*)&mat->insertmode,(PetscEnum*)&addv,1,MPIU_ENUM,MPI_BOR,PetscObjectComm((PetscObject)mat));
844:     if (addv == (ADD_VALUES|INSERT_VALUES)) SETERRQ(PetscObjectComm((PetscObject)mat),PETSC_ERR_ARG_WRONGSTATE,"Some processors inserted others added");
845:   }
846: #endif

848:   if (stash->subset_off_proc && !mat->subsetoffprocentries) { /* We won't use the old scatter context. */
849:     MatStashScatterDestroy_BTS(stash);
850:   }

852:   MatStashBlockTypeSetUp(stash);
853:   MatStashSortCompress_Private(stash,mat->insertmode);
854:   PetscSegBufferGetSize(stash->segsendblocks,&nblocks);
855:   PetscSegBufferExtractInPlace(stash->segsendblocks,&sendblocks);
856:   if (stash->subset_off_proc && mat->subsetoffprocentries) { /* Set up sendhdrs and sendframes for each rank that we sent before */
857:     PetscInt i;
858:     size_t b;
859:     for (i=0,b=0; i<stash->nsendranks; i++) {
860:       stash->sendframes[i].buffer = &sendblocks[b*stash->blocktype_size];
861:       /* sendhdr is never actually sent, but the count is used by MatStashBTSSend_Private */
862:       stash->sendhdr[i].count = 0; /* Might remain empty (in which case we send a zero-sized message) if no values are communicated to that process */
863:       for ( ; b<nblocks; b++) {
864:         MatStashBlock *sendblock_b = (MatStashBlock*)&sendblocks[b*stash->blocktype_size];
865:         if (PetscUnlikely(sendblock_b->row < owners[stash->sendranks[i]])) SETERRQ2(stash->comm,PETSC_ERR_ARG_WRONG,"MAT_SUBSET_OFF_PROC_ENTRIES set, but row %D owned by %d not communicated in initial assembly",sendblock_b->row,stash->sendranks[i]);
866:         if (sendblock_b->row >= owners[stash->sendranks[i]+1]) break;
867:         stash->sendhdr[i].count++;
868:       }
869:     }
870:   } else {                      /* Dynamically count and pack (first time) */
871:     PetscInt sendno;
872:     size_t i,rowstart;

874:     /* Count number of send ranks and allocate for sends */
875:     stash->nsendranks = 0;
876:     for (rowstart=0; rowstart<nblocks; ) {
877:       PetscInt owner;
878:       MatStashBlock *sendblock_rowstart = (MatStashBlock*)&sendblocks[rowstart*stash->blocktype_size];
879:       PetscFindInt(sendblock_rowstart->row,stash->size+1,owners,&owner);
880:       if (owner < 0) owner = -(owner+2);
881:       for (i=rowstart+1; i<nblocks; i++) { /* Move forward through a run of blocks with the same owner */
882:         MatStashBlock *sendblock_i = (MatStashBlock*)&sendblocks[i*stash->blocktype_size];
883:         if (sendblock_i->row >= owners[owner+1]) break;
884:       }
885:       stash->nsendranks++;
886:       rowstart = i;
887:     }
888:     PetscMalloc3(stash->nsendranks,&stash->sendranks,stash->nsendranks,&stash->sendhdr,stash->nsendranks,&stash->sendframes);

890:     /* Set up sendhdrs and sendframes */
891:     sendno = 0;
892:     for (rowstart=0; rowstart<nblocks; ) {
893:       PetscInt owner;
894:       MatStashBlock *sendblock_rowstart = (MatStashBlock*)&sendblocks[rowstart*stash->blocktype_size];
895:       PetscFindInt(sendblock_rowstart->row,stash->size+1,owners,&owner);
896:       if (owner < 0) owner = -(owner+2);
897:       stash->sendranks[sendno] = owner;
898:       for (i=rowstart+1; i<nblocks; i++) { /* Move forward through a run of blocks with the same owner */
899:         MatStashBlock *sendblock_i = (MatStashBlock*)&sendblocks[i*stash->blocktype_size];
900:         if (sendblock_i->row >= owners[owner+1]) break;
901:       }
902:       stash->sendframes[sendno].buffer = sendblock_rowstart;
903:       stash->sendframes[sendno].pending = 0;
904:       stash->sendhdr[sendno].count = i - rowstart;
905:       sendno++;
906:       rowstart = i;
907:     }
908:     if (sendno != stash->nsendranks) SETERRQ2(stash->comm,PETSC_ERR_PLIB,"BTS counted %D sendranks, but %D sends",stash->nsendranks,sendno);
909:   }

911:   /* Encode insertmode on the outgoing messages. If we want to support more than two options, we would need a new
912:    * message or a dummy entry of some sort. */
913:   if (mat->insertmode == INSERT_VALUES) {
914:     size_t i;
915:     for (i=0; i<nblocks; i++) {
916:       MatStashBlock *sendblock_i = (MatStashBlock*)&sendblocks[i*stash->blocktype_size];
917:       sendblock_i->row = -(sendblock_i->row+1);
918:     }
919:   }

921:   if (stash->subset_off_proc && mat->subsetoffprocentries) {
922:     PetscMPIInt i,tag;
923:     PetscCommGetNewTag(stash->comm,&tag);
924:     for (i=0; i<stash->nrecvranks; i++) {
925:       MatStashBTSRecv_Private(stash->comm,&tag,stash->recvranks[i],&stash->recvhdr[i],&stash->recvreqs[i],stash);
926:     }
927:     for (i=0; i<stash->nsendranks; i++) {
928:       MatStashBTSSend_Private(stash->comm,&tag,i,stash->sendranks[i],&stash->sendhdr[i],&stash->sendreqs[i],stash);
929:     }
930:     stash->use_status = PETSC_TRUE; /* Use count from message status. */
931:   } else {
932:     PetscCommBuildTwoSidedFReq(stash->comm,1,MPIU_INT,stash->nsendranks,stash->sendranks,(PetscInt*)stash->sendhdr,
933:                                       &stash->nrecvranks,&stash->recvranks,(PetscInt*)&stash->recvhdr,1,&stash->sendreqs,&stash->recvreqs,
934:                                       MatStashBTSSend_Private,MatStashBTSRecv_Private,stash);
935:     PetscMalloc2(stash->nrecvranks,&stash->some_indices,stash->nrecvranks,&stash->some_statuses);
936:     stash->use_status = PETSC_FALSE; /* Use count from header instead of from message. */
937:   }

939:   PetscSegBufferExtractInPlace(stash->segrecvframe,&stash->recvframes);
940:   stash->recvframe_active = NULL;
941:   stash->recvframe_i      = 0;
942:   stash->some_i           = 0;
943:   stash->some_count       = 0;
944:   stash->recvcount        = 0;
945:   stash->subset_off_proc  = mat->subsetoffprocentries;
946:   stash->insertmode       = &mat->insertmode;
947:   return(0);
948: }

950: static PetscErrorCode MatStashScatterGetMesg_BTS(MatStash *stash,PetscMPIInt *n,PetscInt **row,PetscInt **col,PetscScalar **val,PetscInt *flg)
951: {
953:   MatStashBlock *block;

956:   *flg = 0;
957:   while (!stash->recvframe_active || stash->recvframe_i == stash->recvframe_count) {
958:     if (stash->some_i == stash->some_count) {
959:       if (stash->recvcount == stash->nrecvranks) return(0); /* Done */
960:       MPI_Waitsome(stash->nrecvranks,stash->recvreqs,&stash->some_count,stash->some_indices,stash->use_status?stash->some_statuses:MPI_STATUSES_IGNORE);
961:       stash->some_i = 0;
962:     }
963:     stash->recvframe_active = &stash->recvframes[stash->some_indices[stash->some_i]];
964:     stash->recvframe_count = stash->recvframe_active->count; /* From header; maximum count */
965:     if (stash->use_status) { /* Count what was actually sent */
966:       MPI_Get_count(&stash->some_statuses[stash->some_i],stash->blocktype,&stash->recvframe_count);
967:     }
968:     if (stash->recvframe_count > 0) { /* Check for InsertMode consistency */
969:       block = (MatStashBlock*)&((char*)stash->recvframe_active->buffer)[0];
970:       if (PetscUnlikely(*stash->insertmode == NOT_SET_VALUES)) *stash->insertmode = block->row < 0 ? INSERT_VALUES : ADD_VALUES;
971:       if (PetscUnlikely(*stash->insertmode == INSERT_VALUES && block->row >= 0)) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"Assembling INSERT_VALUES, but rank %d requested ADD_VALUES",stash->recvranks[stash->some_indices[stash->some_i]]);
972:       if (PetscUnlikely(*stash->insertmode == ADD_VALUES && block->row < 0)) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"Assembling ADD_VALUES, but rank %d requested INSERT_VALUES",stash->recvranks[stash->some_indices[stash->some_i]]);
973:     }
974:     stash->some_i++;
975:     stash->recvcount++;
976:     stash->recvframe_i = 0;
977:   }
978:   *n = 1;
979:   block = (MatStashBlock*)&((char*)stash->recvframe_active->buffer)[stash->recvframe_i*stash->blocktype_size];
980:   if (block->row < 0) block->row = -(block->row + 1);
981:   *row = &block->row;
982:   *col = &block->col;
983:   *val = block->vals;
984:   stash->recvframe_i++;
985:   *flg = 1;
986:   return(0);
987: }

989: static PetscErrorCode MatStashScatterEnd_BTS(MatStash *stash)
990: {

994:   MPI_Waitall(stash->nsendranks,stash->sendreqs,MPI_STATUSES_IGNORE);
995:   if (stash->subset_off_proc) { /* Reuse the communication contexts, so consolidate and reset segrecvblocks  */
996:     void *dummy;
997:     PetscSegBufferExtractInPlace(stash->segrecvblocks,&dummy);
998:   } else {                      /* No reuse, so collect everything. */
999:     MatStashScatterDestroy_BTS(stash);
1000:   }

1002:   /* Now update nmaxold to be app 10% more than max n used, this way the
1003:      wastage of space is reduced the next time this stash is used.
1004:      Also update the oldmax, only if it increases */
1005:   if (stash->n) {
1006:     PetscInt bs2     = stash->bs*stash->bs;
1007:     PetscInt oldnmax = ((int)(stash->n * 1.1) + 5)*bs2;
1008:     if (oldnmax > stash->oldnmax) stash->oldnmax = oldnmax;
1009:   }

1011:   stash->nmax       = 0;
1012:   stash->n          = 0;
1013:   stash->reallocs   = -1;
1014:   stash->nprocessed = 0;

1016:   PetscMatStashSpaceDestroy(&stash->space_head);

1018:   stash->space = 0;

1020:   return(0);
1021: }

1023: static PetscErrorCode MatStashScatterDestroy_BTS(MatStash *stash)
1024: {

1028:   PetscSegBufferDestroy(&stash->segsendblocks);
1029:   PetscSegBufferDestroy(&stash->segrecvframe);
1030:   stash->recvframes = NULL;
1031:   PetscSegBufferDestroy(&stash->segrecvblocks);
1032:   if (stash->blocktype != MPI_DATATYPE_NULL) {
1033:     MPI_Type_free(&stash->blocktype);
1034:   }
1035:   stash->nsendranks = 0;
1036:   stash->nrecvranks = 0;
1037:   PetscFree3(stash->sendranks,stash->sendhdr,stash->sendframes);
1038:   PetscFree(stash->sendreqs);
1039:   PetscFree(stash->recvreqs);
1040:   PetscFree(stash->recvranks);
1041:   PetscFree(stash->recvhdr);
1042:   PetscFree2(stash->some_indices,stash->some_statuses);
1043:   return(0);
1044: }
1045: #endif