Actual source code: mmsbaij.c
1: /*$Id: mmsbaij.c,v 1.8 2001/03/23 23:22:26 balay Exp $*/
3: /*
4: Support for the parallel SBAIJ matrix vector multiply
5: */
6: #include "src/mat/impls/baij/mpi/mpibaij.h"
7: #include "src/vec/vecimpl.h"
8: extern int MatSetValues_SeqSBAIJ(Mat,int,int*,int,int*,Scalar*,InsertMode);
10: int MatSetUpMultiply_MPISBAIJ(Mat mat)
11: {
12: Mat_MPIBAIJ *baij = (Mat_MPIBAIJ*)mat->data;
13: Mat_SeqBAIJ *B = (Mat_SeqBAIJ*)(baij->B->data);
14: int Nbs = baij->Nbs,i,j,*indices,*aj = B->j,ierr,ec = 0,*garray;
15: int col,bs = baij->bs,*tmp,*stmp;
16: IS from,to;
17: Vec gvec;
18: #if defined (PETSC_USE_CTABLE)
19: PetscTable gid1_lid1;
20: PetscTablePosition tpos;
21: int gid,lid;
22: #endif
26: #if defined (PETSC_USE_CTABLE)
27: /* use a table - Mark Adams */
28: PetscTableCreate(B->mbs,&gid1_lid1);
29: for (i=0; i<B->mbs; i++) {
30: for (j=0; j<B->ilen[i]; j++) {
31: int data,gid1 = aj[B->i[i]+j] + 1;
32: PetscTableFind(gid1_lid1,gid1,&data) ;
33: if (!data) {
34: /* one based table */
35: PetscTableAdd(gid1_lid1,gid1,++ec);
36: }
37: }
38: }
39: /* form array of columns we need */
40: PetscMalloc((ec+1)*sizeof(int),&garray);
41: PetscMalloc((ec*bs+1)*sizeof(int),&tmp);
42: PetscTableGetHeadPosition(gid1_lid1,&tpos);
43: while (tpos) {
44: PetscTableGetNext(gid1_lid1,&tpos,&gid,&lid);
45: gid--; lid--;
46: garray[lid] = gid;
47: }
48: PetscSortInt(ec,garray);
49: /* qsort(garray, ec, sizeof(int), intcomparcarc); */
50: PetscTableRemoveAll(gid1_lid1);
51: for (i=0; i<ec; i++) {
52: PetscTableAdd(gid1_lid1,garray[i]+1,i+1);
53: }
54: /* compact out the extra columns in B */
55: for (i=0; i<B->mbs; i++) {
56: for (j=0; j<B->ilen[i]; j++) {
57: int gid1 = aj[B->i[i] + j] + 1;
58: PetscTableFind(gid1_lid1,gid1,&lid);
59: lid --;
60: aj[B->i[i]+j] = lid;
61: }
62: }
63: B->nbs = ec;
64: baij->B->n = ec*B->bs;
65: PetscTableDelete(gid1_lid1);
66: /* Mark Adams */
67: #else
68: /* For the first stab we make an array as long as the number of columns */
69: /* mark those columns that are in baij->B */
70: PetscMalloc((Nbs+1)*sizeof(int),&indices);
71: PetscMemzero(indices,Nbs*sizeof(int));
72: for (i=0; i<B->mbs; i++) {
73: for (j=0; j<B->ilen[i]; j++) {
74: if (!indices[aj[B->i[i] + j]]) ec++;
75: indices[aj[B->i[i] + j] ] = 1;
76: }
77: }
79: /* form array of columns we need */
80: PetscMalloc((ec+1)*sizeof(int),&garray);
81: PetscMalloc((ec*bs+1)*sizeof(int),&tmp);
82: ec = 0;
83: for (i=0; i<Nbs; i++) {
84: if (indices[i]) {
85: garray[ec++] = i;
86: }
87: }
89: /* make indices now point into garray */
90: for (i=0; i<ec; i++) {
91: indices[garray[i]] = i;
92: }
94: /* compact out the extra columns in B */
95: for (i=0; i<B->mbs; i++) {
96: for (j=0; j<B->ilen[i]; j++) {
97: aj[B->i[i] + j] = indices[aj[B->i[i] + j]];
98: }
99: }
100: B->nbs = ec;
101: baij->B->n = ec*B->bs;
102: PetscFree(indices);
103: #endif
105: for (i=0,col=0; i<ec; i++) {
106: for (j=0; j<bs; j++,col++) tmp[col] = garray[i]*bs+j;
107: }
108: /* create local vector that is used to scatter into */
109: VecCreateSeq(PETSC_COMM_SELF,ec*bs,&baij->lvec);
111: /* create two temporary index sets for building scatter-gather */
113: /* ISCreateGeneral(PETSC_COMM_SELF,ec*bs,tmp,&from); */
114: for (i=0; i<ec; i++) {
115: garray[i] = bs*garray[i];
116: }
117: ISCreateBlock(PETSC_COMM_SELF,bs,ec,garray,&from);
118: for (i=0,col=0; i<ec; i++) {
119: garray[i] = garray[i]/bs;
120: }
122: PetscMalloc((ec+1)*sizeof(int),&stmp);
123: for (i=0; i<ec; i++) { stmp[i] = bs*i; }
124: ISCreateBlock(PETSC_COMM_SELF,bs,ec,stmp,&to);
125: PetscFree(stmp);
127: /* create temporary global vector to generate scatter context */
128: /* this is inefficient, but otherwise we must do either
129: 1) save garray until the first actual scatter when the vector is known or
130: 2) have another way of generating a scatter context without a vector.*/
131: VecCreateMPI(mat->comm,mat->n,mat->N,&gvec);
133: /* gnerate the scatter context */
134: VecScatterCreate(gvec,from,baij->lvec,to,&baij->Mvctx);
136: /*
137: Post the receives for the first matrix vector product. We sync-chronize after
138: this on the chance that the user immediately calls MatMult() after assemblying
139: the matrix.
140: */
141: VecScatterPostRecvs(gvec,baij->lvec,INSERT_VALUES,SCATTER_FORWARD,baij->Mvctx);
142: MPI_Barrier(mat->comm);
144: PetscLogObjectParent(mat,baij->Mvctx);
145: PetscLogObjectParent(mat,baij->lvec);
146: PetscLogObjectParent(mat,from);
147: PetscLogObjectParent(mat,to);
148: baij->garray = garray;
149: PetscLogObjectMemory(mat,(ec+1)*sizeof(int));
150: ISDestroy(from);
151: ISDestroy(to);
152: VecDestroy(gvec);
153: PetscFree(tmp);
154: return(0);
155: }
158: /*
159: Takes the local part of an already assembled MPIBAIJ matrix
160: and disassembles it. This is to allow new nonzeros into the matrix
161: that require more communication in the matrix vector multiply.
162: Thus certain data-structures must be rebuilt.
164: Kind of slow! But that's what application programmers get when
165: they are sloppy.
166: */
167: int DisAssemble_MPISBAIJ(Mat A)
168: {
169: Mat_MPIBAIJ *baij = (Mat_MPIBAIJ*)A->data;
170: Mat B = baij->B,Bnew;
171: Mat_SeqBAIJ *Bbaij = (Mat_SeqBAIJ*)B->data;
172: int ierr,i,j,mbs=Bbaij->mbs,n = A->N,col,*garray=baij->garray;
173: int k,bs=baij->bs,bs2=baij->bs2,*rvals,*nz,ec,m=A->m;
174: MatScalar *a = Bbaij->a;
175: Scalar *atmp;
176: #if defined(PETSC_USE_MAT_SINGLE)
177: int l;
178: #endif
181: #if defined(PETSC_USE_MAT_SINGLE)
182: PetscMalloc(baij->bs*sizeof(Scalar),&atmp);
183: #endif
184: /* free stuff related to matrix-vec multiply */
185: VecGetSize(baij->lvec,&ec); /* needed for PetscLogObjectMemory below */
186: VecDestroy(baij->lvec); baij->lvec = 0;
187: VecScatterDestroy(baij->Mvctx); baij->Mvctx = 0;
188: if (baij->colmap) {
189: #if defined (PETSC_USE_CTABLE)
190: PetscTableDelete(baij->colmap); baij->colmap = 0;
191: #else
192: PetscFree(baij->colmap);
193: baij->colmap = 0;
194: PetscLogObjectMemory(A,-Bbaij->nbs*sizeof(int));
195: #endif
196: }
198: /* make sure that B is assembled so we can access its values */
199: MatAssemblyBegin(B,MAT_FINAL_ASSEMBLY);
200: MatAssemblyEnd(B,MAT_FINAL_ASSEMBLY);
202: /* invent new B and copy stuff over */
203: PetscMalloc(mbs*sizeof(int),&nz);
204: for (i=0; i<mbs; i++) {
205: nz[i] = Bbaij->i[i+1]-Bbaij->i[i];
206: }
207: MatCreateSeqBAIJ(PETSC_COMM_SELF,baij->bs,m,n,0,nz,&Bnew);
208: PetscFree(nz);
209:
210: PetscMalloc(bs*sizeof(int),&rvals);
211: for (i=0; i<mbs; i++) {
212: rvals[0] = bs*i;
213: for (j=1; j<bs; j++) { rvals[j] = rvals[j-1] + 1; }
214: for (j=Bbaij->i[i]; j<Bbaij->i[i+1]; j++) {
215: col = garray[Bbaij->j[j]]*bs;
216: for (k=0; k<bs; k++) {
217: #if defined(PETSC_USE_MAT_SINGLE)
218: for (l=0; l<bs; l++) atmp[l] = a[j*bs2+l];
219: #else
220: atmp = a+j*bs2;
221: #endif
222: MatSetValues_SeqSBAIJ(Bnew,bs,rvals,1,&col,atmp,B->insertmode);
223: col++;
224: }
225: }
226: }
227: #if defined(PETSC_USE_MAT_SINGLE)
228: PetscFree(atmp);
229: #endif
230: PetscFree(baij->garray);
231: baij->garray = 0;
232: PetscFree(rvals);
233: PetscLogObjectMemory(A,-ec*sizeof(int));
234: MatDestroy(B);
235: PetscLogObjectParent(A,Bnew);
236: baij->B = Bnew;
237: A->was_assembled = PETSC_FALSE;
238: return(0);
239: }