Actual source code: mpimatmatmult.c

  1: #define PETSCMAT_DLL

  3: /*
  4:   Defines matrix-matrix product routines for pairs of MPIAIJ matrices
  5:           C = A * B
  6: */
 7:  #include src/mat/impls/aij/seq/aij.h
 8:  #include src/mat/utils/freespace.h
 9:  #include src/mat/impls/aij/mpi/mpiaij.h
 10:  #include petscbt.h
 11:  #include src/mat/impls/dense/mpi/mpidense.h

 15: PetscErrorCode MatMatMult_MPIAIJ_MPIAIJ(Mat A,Mat B,MatReuse scall,PetscReal fill, Mat *C)
 16: {

 20:   if (scall == MAT_INITIAL_MATRIX){
 21:     MatMatMultSymbolic_MPIAIJ_MPIAIJ(A,B,fill,C);/* numeric product is computed as well */
 22:   } else if (scall == MAT_REUSE_MATRIX){
 23:     MatMatMultNumeric_MPIAIJ_MPIAIJ(A,B,*C);
 24:   } else {
 25:     SETERRQ1(PETSC_ERR_ARG_WRONG,"Invalid MatReuse %d",(int)scall);
 26:   }
 27:   return(0);
 28: }

 32: PetscErrorCode PetscContainerDestroy_Mat_MatMatMultMPI(void *ptr)
 33: {
 34:   PetscErrorCode       ierr;
 35:   Mat_MatMatMultMPI    *mult=(Mat_MatMatMultMPI*)ptr;

 38:   PetscFree(mult->startsj);
 39:   PetscFree(mult->bufa);
 40:   if (mult->isrowa){ISDestroy(mult->isrowa);}
 41:   if (mult->isrowb){ISDestroy(mult->isrowb);}
 42:   if (mult->iscolb){ISDestroy(mult->iscolb);}
 43:   if (mult->C_seq){MatDestroy(mult->C_seq);}
 44:   if (mult->A_loc){MatDestroy(mult->A_loc); }
 45:   if (mult->B_seq){MatDestroy(mult->B_seq);}
 46:   if (mult->B_loc){MatDestroy(mult->B_loc);}
 47:   if (mult->B_oth){MatDestroy(mult->B_oth);}
 48:   PetscFree(mult->abi);
 49:   PetscFree(mult->abj);
 50:   PetscFree(mult);
 51:   return(0);
 52: }

 54: EXTERN PetscErrorCode MatDestroy_AIJ(Mat);
 57: PetscErrorCode MatDestroy_MPIAIJ_MatMatMult(Mat A)
 58: {
 59:   PetscErrorCode     ierr;
 60:   PetscContainer     container;
 61:   Mat_MatMatMultMPI  *mult=PETSC_NULL;

 64:   PetscObjectQuery((PetscObject)A,"Mat_MatMatMultMPI",(PetscObject *)&container);
 65:   if (container) {
 66:     PetscContainerGetPointer(container,(void **)&mult);
 67:   } else {
 68:     SETERRQ(PETSC_ERR_PLIB,"Container does not exit");
 69:   }
 70:   A->ops->destroy = mult->MatDestroy;
 71:   PetscObjectCompose((PetscObject)A,"Mat_MatMatMultMPI",0);
 72:   (*A->ops->destroy)(A);
 73:   PetscContainerDestroy(container);
 74:   return(0);
 75: }

 79: PetscErrorCode MatDuplicate_MPIAIJ_MatMatMult(Mat A, MatDuplicateOption op, Mat *M) {
 80:   PetscErrorCode     ierr;
 81:   Mat_MatMatMultMPI  *mult;
 82:   PetscContainer     container;

 85:   PetscObjectQuery((PetscObject)A,"Mat_MatMatMultMPI",(PetscObject *)&container);
 86:   if (container) {
 87:     PetscContainerGetPointer(container,(void **)&mult);
 88:   } else {
 89:     SETERRQ(PETSC_ERR_PLIB,"Container does not exit");
 90:   }
 91:   /* Note: the container is not duplicated, because it requires deep copying of
 92:      several large data sets (see PetscContainerDestroy_Mat_MatMatMultMPI()).
 93:      These data sets are only used for repeated calling of MatMatMultNumeric(). 
 94:      *M is unlikely being used in this way. Thus we create *M with pure mpiaij format */
 95:   (*mult->MatDuplicate)(A,op,M);
 96:   (*M)->ops->destroy   = mult->MatDestroy;   /* = MatDestroy_MPIAIJ, *M doesn't duplicate A's container! */
 97:   (*M)->ops->duplicate = mult->MatDuplicate; /* = MatDuplicate_MPIAIJ */
 98:   return(0);
 99: }

103: PetscErrorCode MatMatMultSymbolic_MPIAIJ_MPIAIJ(Mat A,Mat B,PetscReal fill,Mat *C)
104: {
105:   PetscErrorCode     ierr;
106:   PetscInt           start,end;
107:   Mat_MatMatMultMPI  *mult;
108:   PetscContainer     container;
109: 
111:   if (A->cmap.rstart != B->rmap.rstart || A->cmap.rend != B->rmap.rend){
112:     SETERRQ4(PETSC_ERR_ARG_SIZ,"Matrix local dimensions are incompatible, (%D, %D) != (%D,%D)",A->cmap.rstart,A->cmap.rend,B->rmap.rstart,B->rmap.rend);
113:   }
114:   PetscNew(Mat_MatMatMultMPI,&mult);

116:   /* create a seq matrix B_seq = submatrix of B by taking rows of B that equal to nonzero col of A */
117:   MatGetBrowsOfAcols(A,B,MAT_INITIAL_MATRIX,&mult->isrowb,&mult->iscolb,&mult->brstart,&mult->B_seq);

119:   /*  create a seq matrix A_seq = submatrix of A by taking all local rows of A */
120:   start = A->rmap.rstart; end = A->rmap.rend;
121:   ISCreateStride(PETSC_COMM_SELF,end-start,start,1,&mult->isrowa);
122:   MatGetLocalMatCondensed(A,MAT_INITIAL_MATRIX,&mult->isrowa,&mult->isrowb,&mult->A_loc);

124:   /* compute C_seq = A_seq * B_seq */
125:   MatMatMult_SeqAIJ_SeqAIJ(mult->A_loc,mult->B_seq,MAT_INITIAL_MATRIX,fill,&mult->C_seq);

127:   /* create mpi matrix C by concatinating C_seq */
128:   PetscObjectReference((PetscObject)mult->C_seq); /* prevent C_seq being destroyed by MatMerge() */
129:   MatMerge(A->comm,mult->C_seq,B->cmap.n,MAT_INITIAL_MATRIX,C);
130: 
131:   /* attach the supporting struct to C for reuse of symbolic C */
132:   PetscContainerCreate(PETSC_COMM_SELF,&container);
133:   PetscContainerSetPointer(container,mult);
134:   PetscObjectCompose((PetscObject)(*C),"Mat_MatMatMultMPI",(PetscObject)container);
135:   PetscContainerSetUserDestroy(container,PetscContainerDestroy_Mat_MatMatMultMPI);
136:   mult->MatDestroy   = (*C)->ops->destroy;
137:   mult->MatDuplicate = (*C)->ops->duplicate;

139:   (*C)->ops->destroy   = MatDestroy_MPIAIJ_MatMatMult;
140:   (*C)->ops->duplicate = MatDuplicate_MPIAIJ_MatMatMult;
141:   return(0);
142: }

144: /* This routine is called ONLY in the case of reusing previously computed symbolic C */
147: PetscErrorCode MatMatMultNumeric_MPIAIJ_MPIAIJ(Mat A,Mat B,Mat C)
148: {
149:   PetscErrorCode     ierr;
150:   Mat                *seq;
151:   Mat_MatMatMultMPI  *mult;
152:   PetscContainer     container;

155:   PetscObjectQuery((PetscObject)C,"Mat_MatMatMultMPI",(PetscObject *)&container);
156:   if (container) {
157:     PetscContainerGetPointer(container,(void **)&mult);
158:   } else {
159:     SETERRQ(PETSC_ERR_PLIB,"Container does not exit");
160:   }

162:   seq = &mult->B_seq;
163:   MatGetSubMatrices(B,1,&mult->isrowb,&mult->iscolb,MAT_REUSE_MATRIX,&seq);
164:   mult->B_seq = *seq;
165: 
166:   seq = &mult->A_loc;
167:   MatGetSubMatrices(A,1,&mult->isrowa,&mult->isrowb,MAT_REUSE_MATRIX,&seq);
168:   mult->A_loc = *seq;

170:   MatMatMult_SeqAIJ_SeqAIJ(mult->A_loc,mult->B_seq,MAT_REUSE_MATRIX,0.0,&mult->C_seq);

172:   PetscObjectReference((PetscObject)mult->C_seq);
173:   MatMerge(A->comm,mult->C_seq,B->cmap.n,MAT_REUSE_MATRIX,&C);
174:   return(0);
175: }

179: PetscErrorCode MatMatMult_MPIAIJ_MPIDense(Mat A,Mat B,MatReuse scall,PetscReal fill,Mat *C)
180: {

184:   if (scall == MAT_INITIAL_MATRIX){
185:     MatMatMultSymbolic_MPIAIJ_MPIDense(A,B,fill,C);
186:   }
187:   MatMatMultNumeric_MPIAIJ_MPIDense(A,B,*C);
188:   return(0);
189: }

191: typedef struct {
192:   Mat         workB;
193:   PetscScalar *rvalues,*svalues;
194:   MPI_Request *rwaits,*swaits;
195: } MPIAIJ_MPIDense;

197: PetscErrorCode MPIAIJ_MPIDenseDestroy(void *ctx)
198: {
199:   MPIAIJ_MPIDense *contents = (MPIAIJ_MPIDense*) ctx;
200:   PetscErrorCode  ierr;

203:   if (contents->workB) {MatDestroy(contents->workB);}
204:   PetscFree4(contents->rvalues,contents->svalues,contents->rwaits,contents->swaits);
205:   PetscFree(contents);
206:   return(0);
207: }

211: PetscErrorCode MatMatMultSymbolic_MPIAIJ_MPIDense(Mat A,Mat B,PetscReal fill,Mat *C)
212: {
213:   PetscErrorCode         ierr;
214:   Mat_MPIAIJ             *aij = (Mat_MPIAIJ*) A->data;
215:   PetscInt               nz = aij->B->cmap.n;
216:   PetscContainer         cont;
217:   MPIAIJ_MPIDense        *contents;
218:   VecScatter             ctx = aij->Mvctx;
219:   VecScatter_MPI_General *from = (VecScatter_MPI_General*) ctx->fromdata;
220:   VecScatter_MPI_General *to   = ( VecScatter_MPI_General*) ctx->todata;

223:   MatMatMultSymbolic_MPIDense_MPIDense(A,B,0.0,C);

225:   PetscContainerCreate(A->comm,&cont);
226:   PetscNew(MPIAIJ_MPIDense,&contents);
227:   PetscContainerSetPointer(cont,contents);
228:   PetscContainerSetUserDestroy(cont,MPIAIJ_MPIDenseDestroy);

230:   /* Create work matrix used to store off processor rows of B needed for local product */
231:   MatCreateSeqDense(PETSC_COMM_SELF,nz,B->cmap.N,PETSC_NULL,&contents->workB);

233:   /* Create work arrays needed */
234:   PetscMalloc4(B->cmap.N*from->starts[from->n],PetscScalar,&contents->rvalues,
235:                       B->cmap.N*to->starts[to->n],PetscScalar,&contents->svalues,
236:                       from->n,MPI_Request,&contents->rwaits,
237:                       to->n,MPI_Request,&contents->swaits);

239:   PetscObjectCompose((PetscObject)(*C),"workB",(PetscObject)cont);
240:   PetscContainerDestroy(cont);
241:   return(0);
242: }

244: /*
245:     Performs an efficient scatter on the rows of B needed by this process; this is
246:     a modification of the VecScatterBegin_() routines.
247: */
248: PetscErrorCode MatMPIDenseScatter(Mat A,Mat B,Mat C,Mat *outworkB)
249: {
250:   Mat_MPIAIJ             *aij = (Mat_MPIAIJ*)A->data;
251:   PetscErrorCode         ierr;
252:   PetscScalar            *b,*w,*svalues,*rvalues;
253:   VecScatter             ctx = aij->Mvctx;
254:   VecScatter_MPI_General *from = (VecScatter_MPI_General*) ctx->fromdata;
255:   VecScatter_MPI_General *to   = ( VecScatter_MPI_General*) ctx->todata;
256:   PetscInt               i,j,k;
257:   PetscMPIInt            *sindices,*sstarts,*sprocs,*rindices,*rstarts,*rprocs,nrecvs;
258:   MPI_Request            *swaits,*rwaits;
259:   MPI_Comm               comm = A->comm;
260:   PetscMPIInt            tag = ctx->tag,ncols = B->cmap.N, nrows = aij->B->cmap.n,imdex,nrowsB = B->rmap.n;
261:   MPI_Status             status;
262:   MPIAIJ_MPIDense        *contents;
263:   PetscContainer         cont;
264:   Mat                    workB;

267:   PetscObjectQuery((PetscObject)C,"workB",(PetscObject*)&cont);
268:   PetscContainerGetPointer(cont,(void**)&contents);

270:   workB = *outworkB = contents->workB;
271:   if (nrows != workB->rmap.n) SETERRQ2(PETSC_ERR_PLIB,"Number of rows of workB %D not equal to columns of aij->B %D",nrows,workB->cmap.n);
272:   sindices  = to->indices;
273:   sstarts   = to->starts;
274:   sprocs    = to->procs;
275:   swaits    = contents->swaits;
276:   svalues   = contents->svalues;

278:   rindices  = from->indices;
279:   rstarts   = from->starts;
280:   rprocs    = from->procs;
281:   rwaits    = contents->rwaits;
282:   rvalues   = contents->rvalues;

284:   MatGetArray(B,&b);
285:   MatGetArray(workB,&w);

287:   for (i=0; i<from->n; i++) {
288:     MPI_Irecv(rvalues+ncols*rstarts[i],ncols*(rstarts[i+1]-rstarts[i]),MPIU_SCALAR,rprocs[i],tag,comm,rwaits+i);
289:   }

291:   for (i=0; i<to->n; i++) {
292:     /* pack a message at a time */
293:     CHKMEMQ;
294:     for (j=0; j<sstarts[i+1]-sstarts[i]; j++){
295:       for (k=0; k<ncols; k++) {
296:         svalues[ncols*(sstarts[i] + j) + k] = b[sindices[sstarts[i]+j] + nrowsB*k];
297:       }
298:     }
299:     CHKMEMQ;
300:     MPI_Isend(svalues+ncols*sstarts[i],ncols*(sstarts[i+1]-sstarts[i]),MPIU_SCALAR,sprocs[i],tag,comm,swaits+i);
301:   }

303:   nrecvs = from->n;
304:   while (nrecvs) {
305:     MPI_Waitany(from->n,rwaits,&imdex,&status);
306:     nrecvs--;
307:     /* unpack a message at a time */
308:     CHKMEMQ;
309:     for (j=0; j<rstarts[imdex+1]-rstarts[imdex]; j++){
310:       for (k=0; k<ncols; k++) {
311:         w[rindices[rstarts[imdex]+j] + nrows*k] = rvalues[ncols*(rstarts[imdex] + j) + k];
312:       }
313:     }
314:     CHKMEMQ;
315:   }
316:   if (to->n) {MPI_Waitall(to->n,swaits,to->sstatus);CHKERRQ(ierr)}

318:   MatRestoreArray(B,&b);
319:   MatRestoreArray(workB,&w);
320:   MatAssemblyBegin(workB,MAT_FINAL_ASSEMBLY);
321:   MatAssemblyEnd(workB,MAT_FINAL_ASSEMBLY);
322:   return(0);
323: }

328: PetscErrorCode MatMatMultNumeric_MPIAIJ_MPIDense(Mat A,Mat B,Mat C)
329: {
330:   PetscErrorCode       ierr;
331:   Mat_MPIAIJ           *aij = (Mat_MPIAIJ*)A->data;
332:   Mat_MPIDense         *bdense = (Mat_MPIDense*)B->data;
333:   Mat_MPIDense         *cdense = (Mat_MPIDense*)C->data;
334:   Mat                  workB;


338:   /* diagonal block of A times all local rows of B*/
339:   MatMatMultNumeric_SeqAIJ_SeqDense(aij->A,bdense->A,cdense->A);

341:   /* get off processor parts of B needed to complete the product */
342:   MatMPIDenseScatter(A,B,C,&workB);

344:   /* off-diagonal block of A times nonlocal rows of B */
345:   MatMatMultNumericAdd_SeqAIJ_SeqDense(aij->B,workB,cdense->A);
346:   MatAssemblyBegin(C,MAT_FINAL_ASSEMBLY);
347:   MatAssemblyEnd(C,MAT_FINAL_ASSEMBLY);
348:   return(0);
349: }