Actual source code: mmaij.c

      1: #define PETSCMAT_DLL

      3: /*
      4:    Support for the parallel AIJ matrix vector multiply
      5: */
     6:  #include src/mat/impls/aij/mpi/mpiaij.h

     10: PetscErrorCode MatSetUpMultiply_MPIAIJ(Mat mat)
     11: {
     12:   Mat_MPIAIJ         *aij = (Mat_MPIAIJ*)mat->data;
     13:   Mat_SeqAIJ         *B = (Mat_SeqAIJ*)(aij->B->data);
     14:   PetscErrorCode     ierr;
     15:   PetscInt           i,j,*aj = B->j,ec = 0,*garray;
     16:   IS                 from,to;
     17:   Vec                gvec;
     18:   PetscTruth         useblockis;
     19: #if defined (PETSC_USE_CTABLE)
     20:   PetscTable         gid1_lid1;
     21:   PetscTablePosition tpos;
     22:   PetscInt           gid,lid;
     23: #else
     24:   PetscInt           N = mat->N,*indices;
     25: #endif

     29: #if defined (PETSC_USE_CTABLE)
     30:   /* use a table - Mark Adams */
     31:   PetscTableCreate(aij->B->m,&gid1_lid1);
     32:   for (i=0; i<aij->B->m; i++) {
     33:     for (j=0; j<B->ilen[i]; j++) {
     34:       PetscInt data,gid1 = aj[B->i[i] + j] + 1;
     35:       PetscTableFind(gid1_lid1,gid1,&data);
     36:       if (!data) {
     37:         /* one based table */
     38:         PetscTableAdd(gid1_lid1,gid1,++ec);
     39:       }
     40:     }
     41:   }
     42:   /* form array of columns we need */
     43:   PetscMalloc((ec+1)*sizeof(PetscInt),&garray);
     44:   PetscTableGetHeadPosition(gid1_lid1,&tpos);
     45:   while (tpos) {
     46:     PetscTableGetNext(gid1_lid1,&tpos,&gid,&lid);
     47:     gid--;
     48:     lid--;
     49:     garray[lid] = gid;
     50:   }
     51:   PetscSortInt(ec,garray); /* sort, and rebuild */
     52:   PetscTableRemoveAll(gid1_lid1);
     53:   for (i=0; i<ec; i++) {
     54:     PetscTableAdd(gid1_lid1,garray[i]+1,i+1);
     55:   }
     56:   /* compact out the extra columns in B */
     57:   for (i=0; i<aij->B->m; i++) {
     58:     for (j=0; j<B->ilen[i]; j++) {
     59:       PetscInt gid1 = aj[B->i[i] + j] + 1;
     60:       PetscTableFind(gid1_lid1,gid1,&lid);
     61:       lid --;
     62:       aj[B->i[i] + j]  = lid;
     63:     }
     64:   }
     65:   aij->B->n = aij->B->N = ec;
     66:   PetscTableDelete(gid1_lid1);
     67:   /* Mark Adams */
     68: #else
     69:   /* For the first stab we make an array as long as the number of columns */
     70:   /* mark those columns that are in aij->B */
     71:   PetscMalloc((N+1)*sizeof(PetscInt),&indices);
     72:   PetscMemzero(indices,N*sizeof(PetscInt));
     73:   for (i=0; i<aij->B->m; i++) {
     74:     for (j=0; j<B->ilen[i]; j++) {
     75:       if (!indices[aj[B->i[i] + j] ]) ec++;
     76:       indices[aj[B->i[i] + j] ] = 1;
     77:     }
     78:   }

     80:   /* form array of columns we need */
     81:   PetscMalloc((ec+1)*sizeof(PetscInt),&garray);
     82:   ec = 0;
     83:   for (i=0; i<N; i++) {
     84:     if (indices[i]) garray[ec++] = i;
     85:   }

     87:   /* make indices now point into garray */
     88:   for (i=0; i<ec; i++) {
     89:     indices[garray[i]] = i;
     90:   }

     92:   /* compact out the extra columns in B */
     93:   for (i=0; i<aij->B->m; i++) {
     94:     for (j=0; j<B->ilen[i]; j++) {
     95:       aj[B->i[i] + j] = indices[aj[B->i[i] + j]];
     96:     }
     97:   }
     98:   aij->B->n = aij->B->N = ec;
     99:   PetscFree(indices);
    100: #endif
    101:   /* create local vector that is used to scatter into */
    102:   VecCreateSeq(PETSC_COMM_SELF,ec,&aij->lvec);

    104:   /* create two temporary Index sets for build scatter gather */
    105:   /*  check for the special case where blocks are communicated for faster VecScatterXXX */
    106:   useblockis = PETSC_TRUE;
    107:   if (mat->bs > 1) {
    108:     PetscInt bs = mat->bs,ibs,ga;
    109:     if (!(ec % bs)) {
    110:       for (i=0; i<ec/bs; i++) {
    111:         if ((ga = garray[ibs = i*bs]) % bs) {
    112:           useblockis = PETSC_FALSE;
    113:           break;
    114:         }
    115:         for (j=1; j<bs; j++) {
    116:           if (garray[ibs+j] != ga+j) {
    117:             useblockis = PETSC_FALSE;
    118:             break;
    119:           }
    120:         }
    121:         if (!useblockis) break;
    122:       }
    123:     }
    124:   }
    125:   if (useblockis) {
    126:     PetscInt *ga,bs = mat->bs,iec = ec/bs;
    127:     PetscLogInfo((mat,"MatSetUpMultiply_MPIAIJ: Using block index set to define scatter\n"));
    128:     PetscMalloc((ec/mat->bs)*sizeof(PetscInt),&ga);
    129:     for (i=0; i<iec; i++) ga[i] = garray[i*bs];
    130:     ISCreateBlock(mat->comm,bs,iec,ga,&from);
    131:     PetscFree(ga);
    132:   } else {
    133:     ISCreateGeneral(mat->comm,ec,garray,&from);
    134:   }
    135:   ISCreateStride(PETSC_COMM_SELF,ec,0,1,&to);

    137:   /* create temporary global vector to generate scatter context */
    138:   /* this is inefficient, but otherwise we must do either
    139:      1) save garray until the first actual scatter when the vector is known or
    140:      2) have another way of generating a scatter context without a vector.*/
    141:   VecCreateMPI(mat->comm,mat->n,mat->N,&gvec);

    143:   /* generate the scatter context */
    144:   VecScatterCreate(gvec,from,aij->lvec,to,&aij->Mvctx);
    145:   PetscLogObjectParent(mat,aij->Mvctx);
    146:   PetscLogObjectParent(mat,aij->lvec);
    147:   PetscLogObjectParent(mat,from);
    148:   PetscLogObjectParent(mat,to);
    149:   aij->garray = garray;
    150:   PetscLogObjectMemory(mat,(ec+1)*sizeof(PetscInt));
    151:   ISDestroy(from);
    152:   ISDestroy(to);
    153:   VecDestroy(gvec);
    154:   return(0);
    155: }

    160: /*
    161:      Takes the local part of an already assembled MPIAIJ matrix
    162:    and disassembles it. This is to allow new nonzeros into the matrix
    163:    that require more communication in the matrix vector multiply.
    164:    Thus certain data-structures must be rebuilt.

    166:    Kind of slow! But that's what application programmers get when
    167:    they are sloppy.
    168: */
    169: PetscErrorCode DisAssemble_MPIAIJ(Mat A)
    170: {
    171:   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)A->data;
    172:   Mat            B = aij->B,Bnew;
    173:   Mat_SeqAIJ     *Baij = (Mat_SeqAIJ*)B->data;
    175:   PetscInt       i,j,m = B->m,n = A->N,col,ct = 0,*garray = aij->garray,*nz,ec;
    176:   PetscScalar    v;

    179:   /* free stuff related to matrix-vec multiply */
    180:   VecGetSize(aij->lvec,&ec); /* needed for PetscLogObjectMemory below */
    181:   VecDestroy(aij->lvec); aij->lvec = 0;
    182:   VecScatterDestroy(aij->Mvctx); aij->Mvctx = 0;
    183:   if (aij->colmap) {
    184: #if defined (PETSC_USE_CTABLE)
    185:     PetscTableDelete(aij->colmap);
    186:     aij->colmap = 0;
    187: #else
    188:     PetscFree(aij->colmap);
    189:     aij->colmap = 0;
    190:     PetscLogObjectMemory(A,-aij->B->n*sizeof(PetscInt));
    191: #endif
    192:   }

    194:   /* make sure that B is assembled so we can access its values */
    195:   MatAssemblyBegin(B,MAT_FINAL_ASSEMBLY);
    196:   MatAssemblyEnd(B,MAT_FINAL_ASSEMBLY);

    198:   /* invent new B and copy stuff over */
    199:   PetscMalloc((m+1)*sizeof(PetscInt),&nz);
    200:   for (i=0; i<m; i++) {
    201:     nz[i] = Baij->i[i+1] - Baij->i[i];
    202:   }
    203:   MatCreate(PETSC_COMM_SELF,&Bnew);
    204:   MatSetSizes(Bnew,m,n,m,n);
    205:   MatSetType(Bnew,B->type_name);
    206:   MatSeqAIJSetPreallocation(Bnew,0,nz);
    207:   PetscFree(nz);
    208:   for (i=0; i<m; i++) {
    209:     for (j=Baij->i[i]; j<Baij->i[i+1]; j++) {
    210:       col  = garray[Baij->j[ct]];
    211:       v    = Baij->a[ct++];
    212:       MatSetValues(Bnew,1,&i,1,&col,&v,B->insertmode);
    213:     }
    214:   }
    215:   PetscFree(aij->garray);
    216:   aij->garray = 0;
    217:   PetscLogObjectMemory(A,-ec*sizeof(PetscInt));
    218:   MatDestroy(B);
    219:   PetscLogObjectParent(A,Bnew);
    220:   aij->B = Bnew;
    221:   A->was_assembled = PETSC_FALSE;
    222:   return(0);
    223: }

    225: /*      ugly stuff added for Glenn someday we should fix this up */

    227: static PetscInt *auglyrmapd = 0,*auglyrmapo = 0;  /* mapping from the local ordering to the "diagonal" and "off-diagonal"
    228:                                       parts of the local matrix */
    229: static Vec auglydd = 0,auglyoo = 0;   /* work vectors used to scale the two parts of the local matrix */

    234: PetscErrorCode MatMPIAIJDiagonalScaleLocalSetUp(Mat inA,Vec scale)
    235: {
    236:   Mat_MPIAIJ     *ina = (Mat_MPIAIJ*) inA->data; /*access private part of matrix */
    238:   PetscInt       i,n,nt,cstart,cend,no,*garray = ina->garray,*lindices;
    239:   PetscInt       *r_rmapd,*r_rmapo;
    240:
    242:   MatGetOwnershipRange(inA,&cstart,&cend);
    243:   MatGetSize(ina->A,PETSC_NULL,&n);
    244:   PetscMalloc((inA->mapping->n+1)*sizeof(PetscInt),&r_rmapd);
    245:   PetscMemzero(r_rmapd,inA->mapping->n*sizeof(PetscInt));
    246:   nt   = 0;
    247:   for (i=0; i<inA->mapping->n; i++) {
    248:     if (inA->mapping->indices[i] >= cstart && inA->mapping->indices[i] < cend) {
    249:       nt++;
    250:       r_rmapd[i] = inA->mapping->indices[i] + 1;
    251:     }
    252:   }
    253:   if (nt != n) SETERRQ2(PETSC_ERR_PLIB,"Hmm nt %D n %D",nt,n);
    254:   PetscMalloc((n+1)*sizeof(PetscInt),&auglyrmapd);
    255:   for (i=0; i<inA->mapping->n; i++) {
    256:     if (r_rmapd[i]){
    257:       auglyrmapd[(r_rmapd[i]-1)-cstart] = i;
    258:     }
    259:   }
    260:   PetscFree(r_rmapd);
    261:   VecCreateSeq(PETSC_COMM_SELF,n,&auglydd);

    263:   PetscMalloc((inA->N+1)*sizeof(PetscInt),&lindices);
    264:   PetscMemzero(lindices,inA->N*sizeof(PetscInt));
    265:   for (i=0; i<ina->B->n; i++) {
    266:     lindices[garray[i]] = i+1;
    267:   }
    268:   no   = inA->mapping->n - nt;
    269:   PetscMalloc((inA->mapping->n+1)*sizeof(PetscInt),&r_rmapo);
    270:   PetscMemzero(r_rmapo,inA->mapping->n*sizeof(PetscInt));
    271:   nt   = 0;
    272:   for (i=0; i<inA->mapping->n; i++) {
    273:     if (lindices[inA->mapping->indices[i]]) {
    274:       nt++;
    275:       r_rmapo[i] = lindices[inA->mapping->indices[i]];
    276:     }
    277:   }
    278:   if (nt > no) SETERRQ2(PETSC_ERR_PLIB,"Hmm nt %D no %D",nt,n);
    279:   PetscFree(lindices);
    280:   PetscMalloc((nt+1)*sizeof(PetscInt),&auglyrmapo);
    281:   for (i=0; i<inA->mapping->n; i++) {
    282:     if (r_rmapo[i]){
    283:       auglyrmapo[(r_rmapo[i]-1)] = i;
    284:     }
    285:   }
    286:   PetscFree(r_rmapo);
    287:   VecCreateSeq(PETSC_COMM_SELF,nt,&auglyoo);

    289:   return(0);
    290: }

    294: PetscErrorCode MatMPIAIJDiagonalScaleLocal(Mat A,Vec scale)
    295: {
    296:   /* This routine should really be abandoned as it duplicates MatDiagonalScaleLocal */
    297:   PetscErrorCode ierr,(*f)(Mat,Vec);

    300:   PetscObjectQueryFunction((PetscObject)A,"MatDiagonalScaleLocal_C",(void (**)(void))&f);
    301:   if (f) {
    302:     (*f)(A,scale);
    303:   }
    304:   return(0);
    305: }

    310: PetscErrorCode PETSCMAT_DLLEXPORT MatDiagonalScaleLocal_MPIAIJ(Mat A,Vec scale)
    311: {
    312:   Mat_MPIAIJ     *a = (Mat_MPIAIJ*) A->data; /*access private part of matrix */
    314:   PetscInt       n,i;
    315:   PetscScalar    *d,*o,*s;
    316:
    318:   if (!auglyrmapd) {
    319:     MatMPIAIJDiagonalScaleLocalSetUp(A,scale);
    320:   }

    322:   VecGetArray(scale,&s);
    323:
    324:   VecGetLocalSize(auglydd,&n);
    325:   VecGetArray(auglydd,&d);
    326:   for (i=0; i<n; i++) {
    327:     d[i] = s[auglyrmapd[i]]; /* copy "diagonal" (true local) portion of scale into dd vector */
    328:   }
    329:   VecRestoreArray(auglydd,&d);
    330:   /* column scale "diagonal" portion of local matrix */
    331:   MatDiagonalScale(a->A,PETSC_NULL,auglydd);

    333:   VecGetLocalSize(auglyoo,&n);
    334:   VecGetArray(auglyoo,&o);
    335:   for (i=0; i<n; i++) {
    336:     o[i] = s[auglyrmapo[i]]; /* copy "off-diagonal" portion of scale into oo vector */
    337:   }
    338:   VecRestoreArray(scale,&s);
    339:   VecRestoreArray(auglyoo,&o);
    340:   /* column scale "off-diagonal" portion of local matrix */
    341:   MatDiagonalScale(a->B,PETSC_NULL,auglyoo);

    343:   return(0);
    344: }