Actual source code: mmsell.c

petsc-master 2020-11-28
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  1: /*
  2:    Support for the parallel SELL matrix vector multiply
  3: */
  4: #include <../src/mat/impls/sell/mpi/mpisell.h>
  5: #include <petsc/private/isimpl.h>

  7: /*
  8:    Takes the local part of an already assembled MPISELL matrix
  9:    and disassembles it. This is to allow new nonzeros into the matrix
 10:    that require more communication in the matrix vector multiply.
 11:    Thus certain data-structures must be rebuilt.

 13:    Kind of slow! But that's what application programmers get when
 14:    they are sloppy.
 15: */
 16: PetscErrorCode MatDisAssemble_MPISELL(Mat A)
 17: {
 18:   Mat_MPISELL    *sell=(Mat_MPISELL*)A->data;
 19:   Mat            B=sell->B,Bnew;
 20:   Mat_SeqSELL    *Bsell=(Mat_SeqSELL*)B->data;
 21:   PetscInt       i,j,totalslices,N=A->cmap->N,ec,row;
 22:   PetscBool      isnonzero;

 26:   /* free stuff related to matrix-vec multiply */
 27:   VecGetSize(sell->lvec,&ec); /* needed for PetscLogObjectMemory below */
 28:   VecDestroy(&sell->lvec);
 29:   VecScatterDestroy(&sell->Mvctx);
 30:   if (sell->colmap) {
 31: #if defined(PETSC_USE_CTABLE)
 32:     PetscTableDestroy(&sell->colmap);
 33: #else
 34:     PetscFree(sell->colmap);
 35:     PetscLogObjectMemory((PetscObject)A,-sell->B->cmap->n*sizeof(PetscInt));
 36: #endif
 37:   }

 39:   /* make sure that B is assembled so we can access its values */
 40:   MatAssemblyBegin(B,MAT_FINAL_ASSEMBLY);
 41:   MatAssemblyEnd(B,MAT_FINAL_ASSEMBLY);

 43:   /* invent new B and copy stuff over */
 44:   MatCreate(PETSC_COMM_SELF,&Bnew);
 45:   MatSetSizes(Bnew,B->rmap->n,N,B->rmap->n,N);
 46:   MatSetBlockSizesFromMats(Bnew,A,A);
 47:   MatSetType(Bnew,((PetscObject)B)->type_name);
 48:   MatSeqSELLSetPreallocation(Bnew,0,Bsell->rlen);
 49:   if (Bsell->nonew >= 0) { /* Inherit insertion error options (if positive). */
 50:     ((Mat_SeqSELL*)Bnew->data)->nonew = Bsell->nonew;
 51:   }

 53:   /*
 54:    Ensure that B's nonzerostate is monotonically increasing.
 55:    Or should this follow the MatSetValues() loop to preserve B's nonzerstate across a MatDisAssemble() call?
 56:    */
 57:   Bnew->nonzerostate = B->nonzerostate;

 59:   totalslices = B->rmap->n/8+((B->rmap->n & 0x07)?1:0); /* floor(n/8) */
 60:   for (i=0; i<totalslices; i++) { /* loop over slices */
 61:     for (j=Bsell->sliidx[i],row=0; j<Bsell->sliidx[i+1]; j++,row=((row+1)&0x07)) {
 62:       isnonzero = (PetscBool)((j-Bsell->sliidx[i])/8 < Bsell->rlen[8*i+row]);
 63:       if (isnonzero) {
 64:         MatSetValue(Bnew,8*i+row,sell->garray[Bsell->colidx[j]],Bsell->val[j],B->insertmode);
 65:       }
 66:     }
 67:   }

 69:   PetscFree(sell->garray);
 70:   PetscLogObjectMemory((PetscObject)A,-ec*sizeof(PetscInt));
 71:   MatDestroy(&B);
 72:   PetscLogObjectParent((PetscObject)A,(PetscObject)Bnew);

 74:   sell->B          = Bnew;
 75:   A->was_assembled = PETSC_FALSE;
 76:   A->assembled     = PETSC_FALSE;
 77:   return(0);
 78: }

 80: PetscErrorCode MatSetUpMultiply_MPISELL(Mat mat)
 81: {
 82:   Mat_MPISELL    *sell=(Mat_MPISELL*)mat->data;
 83:   Mat_SeqSELL    *B=(Mat_SeqSELL*)(sell->B->data);
 85:   PetscInt       i,j,*bcolidx=B->colidx,ec=0,*garray,totalslices;
 86:   IS             from,to;
 87:   Vec            gvec;
 88:   PetscBool      isnonzero;
 89: #if defined(PETSC_USE_CTABLE)
 90:   PetscTable         gid1_lid1;
 91:   PetscTablePosition tpos;
 92:   PetscInt           gid,lid;
 93: #else
 94:   PetscInt N = mat->cmap->N,*indices;
 95: #endif

 98:   totalslices = sell->B->rmap->n/8+((sell->B->rmap->n & 0x07)?1:0); /* floor(n/8) */

100:   /* ec counts the number of columns that contain nonzeros */
101: #if defined(PETSC_USE_CTABLE)
102:   /* use a table */
103:   PetscTableCreate(sell->B->rmap->n,mat->cmap->N+1,&gid1_lid1);
104:   for (i=0; i<totalslices; i++) { /* loop over slices */
105:     for (j=B->sliidx[i]; j<B->sliidx[i+1]; j++) {
106:       isnonzero = (PetscBool)((j-B->sliidx[i])/8 < B->rlen[(i<<3)+(j&0x07)]);
107:       if (isnonzero) { /* check the mask bit */
108:         PetscInt data,gid1 = bcolidx[j] + 1;
109:         PetscTableFind(gid1_lid1,gid1,&data);
110:         if (!data) {
111:           /* one based table */
112:           PetscTableAdd(gid1_lid1,gid1,++ec,INSERT_VALUES);
113:         }
114:       }
115:     }
116:   }

118:   /* form array of columns we need */
119:   PetscMalloc1(ec+1,&garray);
120:   PetscTableGetHeadPosition(gid1_lid1,&tpos);
121:   while (tpos) {
122:     PetscTableGetNext(gid1_lid1,&tpos,&gid,&lid);
123:     gid--;
124:     lid--;
125:     garray[lid] = gid;
126:   }
127:   PetscSortInt(ec,garray); /* sort, and rebuild */
128:   PetscTableRemoveAll(gid1_lid1);
129:   for (i=0; i<ec; i++) {
130:     PetscTableAdd(gid1_lid1,garray[i]+1,i+1,INSERT_VALUES);
131:   }

133:   /* compact out the extra columns in B */
134:   for (i=0; i<totalslices; i++) { /* loop over slices */
135:     for (j=B->sliidx[i]; j<B->sliidx[i+1]; j++) {
136:       isnonzero = (PetscBool)((j-B->sliidx[i])/8 < B->rlen[(i<<3)+(j&0x07)]);
137:       if (isnonzero) {
138:         PetscInt gid1 = bcolidx[j] + 1;
139:         PetscTableFind(gid1_lid1,gid1,&lid);
140:         lid--;
141:         bcolidx[j] = lid;
142:       }
143:     }
144:   }
145:   PetscLayoutDestroy(&sell->B->cmap);
146:   PetscLayoutCreateFromSizes(PetscObjectComm((PetscObject)sell->B),ec,ec,1,&sell->B->cmap);
147:   PetscTableDestroy(&gid1_lid1);
148: #else
149:   /* Make an array as long as the number of columns */
150:   PetscCalloc1(N+1,&indices);
151:   /* mark those columns that are in sell->B */
152:   for (i=0; i<totalslices; i++) { /* loop over slices */
153:     for (j=B->sliidx[i]; j<B->sliidx[i+1]; j++) {
154:       isnonzero = (PetscBool)((j-B->sliidx[i])/8 < B->rlen[(i<<3)+(j&0x07)]);
155:       if (isnonzero) {
156:         if (!indices[bcolidx[j]]) ec++;
157:         indices[bcolidx[j]] = 1;
158:       }
159:     }
160:   }

162:   /* form array of columns we need */
163:   PetscMalloc1(ec+1,&garray);
164:   ec   = 0;
165:   for (i=0; i<N; i++) {
166:     if (indices[i]) garray[ec++] = i;
167:   }

169:   /* make indices now point into garray */
170:   for (i=0; i<ec; i++) {
171:     indices[garray[i]] = i;
172:   }

174:   /* compact out the extra columns in B */
175:   for (i=0; i<totalslices; i++) { /* loop over slices */
176:     for (j=B->sliidx[i]; j<B->sliidx[i+1]; j++) {
177:       isnonzero = (PetscBool)((j-B->sliidx[i])/8 < B->rlen[(i<<3)+(j&0x07)]);
178:       if (isnonzero) bcolidx[j] = indices[bcolidx[j]];
179:     }
180:   }
181:   PetscLayoutDestroy(&sell->B->cmap);
182:   PetscLayoutCreateFromSizes(PetscObjectComm((PetscObject)sell->B),ec,ec,1,&sell->B->cmap);
183:   PetscFree(indices);
184: #endif
185:   /* create local vector that is used to scatter into */
186:   VecCreateSeq(PETSC_COMM_SELF,ec,&sell->lvec);
187:   /* create two temporary Index sets for build scatter gather */
188:   ISCreateGeneral(PETSC_COMM_SELF,ec,garray,PETSC_COPY_VALUES,&from);
189:   ISCreateStride(PETSC_COMM_SELF,ec,0,1,&to);

191:   /* create temporary global vector to generate scatter context */
192:   /* This does not allocate the array's memory so is efficient */
193:   VecCreateMPIWithArray(PetscObjectComm((PetscObject)mat),1,mat->cmap->n,mat->cmap->N,NULL,&gvec);

195:   /* generate the scatter context */
196:   VecScatterCreate(gvec,from,sell->lvec,to,&sell->Mvctx);
197:   PetscLogObjectParent((PetscObject)mat,(PetscObject)sell->Mvctx);
198:   PetscLogObjectParent((PetscObject)mat,(PetscObject)sell->lvec);
199:   PetscLogObjectParent((PetscObject)mat,(PetscObject)from);
200:   PetscLogObjectParent((PetscObject)mat,(PetscObject)to);

202:   sell->garray = garray;

204:   PetscLogObjectMemory((PetscObject)mat,(ec+1)*sizeof(PetscInt));
205:   ISDestroy(&from);
206:   ISDestroy(&to);
207:   VecDestroy(&gvec);
208:   return(0);
209: }

211: /*      ugly stuff added for Glenn someday we should fix this up */
212: static PetscInt *auglyrmapd = NULL,*auglyrmapo = NULL; /* mapping from the local ordering to the "diagonal" and "off-diagonal" parts of the local matrix */
213: static Vec auglydd          = NULL,auglyoo     = NULL; /* work vectors used to scale the two parts of the local matrix */

215: PetscErrorCode MatMPISELLDiagonalScaleLocalSetUp(Mat inA,Vec scale)
216: {
217:   Mat_MPISELL    *ina=(Mat_MPISELL*)inA->data; /*access private part of matrix */
219:   PetscInt       i,n,nt,cstart,cend,no,*garray=ina->garray,*lindices;
220:   PetscInt       *r_rmapd,*r_rmapo;

223:   MatGetOwnershipRange(inA,&cstart,&cend);
224:   MatGetSize(ina->A,NULL,&n);
225:   PetscCalloc1(inA->rmap->mapping->n+1,&r_rmapd);
226:   nt   = 0;
227:   for (i=0; i<inA->rmap->mapping->n; i++) {
228:     if (inA->rmap->mapping->indices[i] >= cstart && inA->rmap->mapping->indices[i] < cend) {
229:       nt++;
230:       r_rmapd[i] = inA->rmap->mapping->indices[i] + 1;
231:     }
232:   }
233:   if (nt != n) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_PLIB,"Hmm nt %D n %D",nt,n);
234:   PetscMalloc1(n+1,&auglyrmapd);
235:   for (i=0; i<inA->rmap->mapping->n; i++) {
236:     if (r_rmapd[i]) {
237:       auglyrmapd[(r_rmapd[i]-1)-cstart] = i;
238:     }
239:   }
240:   PetscFree(r_rmapd);
241:   VecCreateSeq(PETSC_COMM_SELF,n,&auglydd);
242:   PetscCalloc1(inA->cmap->N+1,&lindices);
243:   for (i=0; i<ina->B->cmap->n; i++) {
244:     lindices[garray[i]] = i+1;
245:   }
246:   no   = inA->rmap->mapping->n - nt;
247:   PetscCalloc1(inA->rmap->mapping->n+1,&r_rmapo);
248:   nt   = 0;
249:   for (i=0; i<inA->rmap->mapping->n; i++) {
250:     if (lindices[inA->rmap->mapping->indices[i]]) {
251:       nt++;
252:       r_rmapo[i] = lindices[inA->rmap->mapping->indices[i]];
253:     }
254:   }
255:   if (nt > no) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_PLIB,"Hmm nt %D no %D",nt,n);
256:   PetscFree(lindices);
257:   PetscMalloc1(nt+1,&auglyrmapo);
258:   for (i=0; i<inA->rmap->mapping->n; i++) {
259:     if (r_rmapo[i]) {
260:       auglyrmapo[(r_rmapo[i]-1)] = i;
261:     }
262:   }
263:   PetscFree(r_rmapo);
264:   VecCreateSeq(PETSC_COMM_SELF,nt,&auglyoo);
265:   return(0);
266: }

268: PetscErrorCode MatDiagonalScaleLocal_MPISELL(Mat A,Vec scale)
269: {
270:   Mat_MPISELL       *a=(Mat_MPISELL*)A->data; /*access private part of matrix */
271:   PetscErrorCode    ierr;
272:   PetscInt          n,i;
273:   PetscScalar       *d,*o;
274:   const PetscScalar *s;

277:   if (!auglyrmapd) {
278:     MatMPISELLDiagonalScaleLocalSetUp(A,scale);
279:   }
280:   VecGetArrayRead(scale,&s);
281:   VecGetLocalSize(auglydd,&n);
282:   VecGetArray(auglydd,&d);
283:   for (i=0; i<n; i++) {
284:     d[i] = s[auglyrmapd[i]]; /* copy "diagonal" (true local) portion of scale into dd vector */
285:   }
286:   VecRestoreArray(auglydd,&d);
287:   /* column scale "diagonal" portion of local matrix */
288:   MatDiagonalScale(a->A,NULL,auglydd);
289:   VecGetLocalSize(auglyoo,&n);
290:   VecGetArray(auglyoo,&o);
291:   for (i=0; i<n; i++) {
292:     o[i] = s[auglyrmapo[i]]; /* copy "off-diagonal" portion of scale into oo vector */
293:   }
294:   VecRestoreArrayRead(scale,&s);
295:   VecRestoreArray(auglyoo,&o);
296:   /* column scale "off-diagonal" portion of local matrix */
297:   MatDiagonalScale(a->B,NULL,auglyoo);
298:   return(0);
299: }