Actual source code: mmaij.c
petsc-3.13.6 2020-09-29
2: /*
3: Support for the parallel AIJ matrix vector multiply
4: */
5: #include <../src/mat/impls/aij/mpi/mpiaij.h>
6: #include <petsc/private/vecimpl.h>
7: #include <petsc/private/isimpl.h>
9: PetscErrorCode MatSetUpMultiply_MPIAIJ(Mat mat)
10: {
11: Mat_MPIAIJ *aij = (Mat_MPIAIJ*)mat->data;
12: Mat_SeqAIJ *B = (Mat_SeqAIJ*)(aij->B->data);
14: PetscInt i,j,*aj = B->j,ec = 0,*garray;
15: IS from,to;
16: Vec gvec;
17: #if defined(PETSC_USE_CTABLE)
18: PetscTable gid1_lid1;
19: PetscTablePosition tpos;
20: PetscInt gid,lid;
21: #else
22: PetscInt N = mat->cmap->N,*indices;
23: #endif
26: if (!aij->garray) {
27: #if defined(PETSC_USE_CTABLE)
28: /* use a table */
29: PetscTableCreate(aij->B->rmap->n,mat->cmap->N+1,&gid1_lid1);
30: for (i=0; i<aij->B->rmap->n; i++) {
31: for (j=0; j<B->ilen[i]; j++) {
32: PetscInt data,gid1 = aj[B->i[i] + j] + 1;
33: PetscTableFind(gid1_lid1,gid1,&data);
34: if (!data) {
35: /* one based table */
36: PetscTableAdd(gid1_lid1,gid1,++ec,INSERT_VALUES);
37: }
38: }
39: }
40: /* form array of columns we need */
41: PetscMalloc1(ec+1,&garray);
42: PetscTableGetHeadPosition(gid1_lid1,&tpos);
43: while (tpos) {
44: PetscTableGetNext(gid1_lid1,&tpos,&gid,&lid);
45: gid--;
46: lid--;
47: garray[lid] = gid;
48: }
49: PetscSortInt(ec,garray); /* sort, and rebuild */
50: PetscTableRemoveAll(gid1_lid1);
51: for (i=0; i<ec; i++) {
52: PetscTableAdd(gid1_lid1,garray[i]+1,i+1,INSERT_VALUES);
53: }
54: /* compact out the extra columns in B */
55: for (i=0; i<aij->B->rmap->n; i++) {
56: for (j=0; j<B->ilen[i]; j++) {
57: PetscInt 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: PetscLayoutDestroy(&aij->B->cmap);
64: PetscLayoutCreateFromSizes(PetscObjectComm((PetscObject)aij->B),ec,ec,1,&aij->B->cmap);
65: PetscTableDestroy(&gid1_lid1);
66: #else
67: /* Make an array as long as the number of columns */
68: /* mark those columns that are in aij->B */
69: PetscCalloc1(N+1,&indices);
70: for (i=0; i<aij->B->rmap->n; i++) {
71: for (j=0; j<B->ilen[i]; j++) {
72: if (!indices[aj[B->i[i] + j]]) ec++;
73: indices[aj[B->i[i] + j]] = 1;
74: }
75: }
77: /* form array of columns we need */
78: PetscMalloc1(ec+1,&garray);
79: ec = 0;
80: for (i=0; i<N; i++) {
81: if (indices[i]) garray[ec++] = i;
82: }
84: /* make indices now point into garray */
85: for (i=0; i<ec; i++) {
86: indices[garray[i]] = i;
87: }
89: /* compact out the extra columns in B */
90: for (i=0; i<aij->B->rmap->n; i++) {
91: for (j=0; j<B->ilen[i]; j++) {
92: aj[B->i[i] + j] = indices[aj[B->i[i] + j]];
93: }
94: }
95: PetscLayoutDestroy(&aij->B->cmap);
96: PetscLayoutCreateFromSizes(PetscObjectComm((PetscObject)aij->B),ec,ec,1,&aij->B->cmap);
97: PetscFree(indices);
98: #endif
99: } else {
100: garray = aij->garray;
101: }
103: if (!aij->lvec) {
104: /* create local vector that is used to scatter into */
105: VecCreateSeq(PETSC_COMM_SELF,ec,&aij->lvec);
106: } else {
107: VecGetSize(aij->lvec,&ec);
108: }
110: /* create two temporary Index sets for build scatter gather */
111: ISCreateGeneral(PETSC_COMM_SELF,ec,garray,PETSC_COPY_VALUES,&from);
112: ISCreateStride(PETSC_COMM_SELF,ec,0,1,&to);
114: /* create temporary global vector to generate scatter context */
115: /* This does not allocate the array's memory so is efficient */
116: VecCreateMPIWithArray(PetscObjectComm((PetscObject)mat),1,mat->cmap->n,mat->cmap->N,NULL,&gvec);
118: /* generate the scatter context */
119: if (aij->Mvctx_mpi1_flg) {
120: VecScatterDestroy(&aij->Mvctx_mpi1);
121: VecScatterCreate(gvec,from,aij->lvec,to,&aij->Mvctx_mpi1);
122: VecScatterSetType(aij->Mvctx_mpi1,VECSCATTERMPI1);
123: PetscLogObjectParent((PetscObject)mat,(PetscObject)aij->Mvctx_mpi1);
124: } else {
125: VecScatterDestroy(&aij->Mvctx);
126: VecScatterCreate(gvec,from,aij->lvec,to,&aij->Mvctx);
127: PetscLogObjectParent((PetscObject)mat,(PetscObject)aij->Mvctx);
128: PetscLogObjectParent((PetscObject)mat,(PetscObject)aij->lvec);
129: PetscLogObjectMemory((PetscObject)mat,(ec+1)*sizeof(PetscInt));
130: }
131: aij->garray = garray;
133: PetscLogObjectParent((PetscObject)mat,(PetscObject)from);
134: PetscLogObjectParent((PetscObject)mat,(PetscObject)to);
136: ISDestroy(&from);
137: ISDestroy(&to);
138: VecDestroy(&gvec);
139: return(0);
140: }
142: /*
143: Takes the local part of an already assembled MPIAIJ matrix
144: and disassembles it. This is to allow new nonzeros into the matrix
145: that require more communication in the matrix vector multiply.
146: Thus certain data-structures must be rebuilt.
148: Kind of slow! But that's what Section 1.5 Writing Application Codes with PETSc programmers get when
149: they are sloppy.
150: */
151: PetscErrorCode MatDisAssemble_MPIAIJ(Mat A)
152: {
153: Mat_MPIAIJ *aij = (Mat_MPIAIJ*)A->data;
154: Mat B = aij->B,Bnew;
155: Mat_SeqAIJ *Baij = (Mat_SeqAIJ*)B->data;
157: PetscInt i,j,m = B->rmap->n,n = A->cmap->N,col,ct = 0,*garray = aij->garray,*nz,ec;
158: PetscScalar v;
161: /* free stuff related to matrix-vec multiply */
162: VecGetSize(aij->lvec,&ec); /* needed for PetscLogObjectMemory below */
163: VecDestroy(&aij->lvec);
164: if (aij->colmap) {
165: #if defined(PETSC_USE_CTABLE)
166: PetscTableDestroy(&aij->colmap);
167: #else
168: PetscFree(aij->colmap);
169: PetscLogObjectMemory((PetscObject)A,-aij->B->cmap->n*sizeof(PetscInt));
170: #endif
171: }
173: /* make sure that B is assembled so we can access its values */
174: MatAssemblyBegin(B,MAT_FINAL_ASSEMBLY);
175: MatAssemblyEnd(B,MAT_FINAL_ASSEMBLY);
177: /* invent new B and copy stuff over */
178: PetscMalloc1(m+1,&nz);
179: for (i=0; i<m; i++) {
180: nz[i] = Baij->i[i+1] - Baij->i[i];
181: }
182: MatCreate(PETSC_COMM_SELF,&Bnew);
183: MatSetSizes(Bnew,m,n,m,n);
184: MatSetBlockSizesFromMats(Bnew,A,A);
185: MatSetType(Bnew,((PetscObject)B)->type_name);
186: MatSeqAIJSetPreallocation(Bnew,0,nz);
188: if (Baij->nonew >= 0) { /* Inherit insertion error options (if positive). */
189: ((Mat_SeqAIJ*)Bnew->data)->nonew = Baij->nonew;
190: }
192: /*
193: Ensure that B's nonzerostate is monotonically increasing.
194: Or should this follow the MatSetValues() loop to preserve B's nonzerstate across a MatDisAssemble() call?
195: */
196: Bnew->nonzerostate = B->nonzerostate;
198: PetscFree(nz);
199: for (i=0; i<m; i++) {
200: for (j=Baij->i[i]; j<Baij->i[i+1]; j++) {
201: col = garray[Baij->j[ct]];
202: v = Baij->a[ct++];
203: MatSetValues(Bnew,1,&i,1,&col,&v,B->insertmode);
204: }
205: }
206: PetscFree(aij->garray);
207: PetscLogObjectMemory((PetscObject)A,-ec*sizeof(PetscInt));
208: MatDestroy(&B);
209: PetscLogObjectParent((PetscObject)A,(PetscObject)Bnew);
211: aij->B = Bnew;
212: A->was_assembled = PETSC_FALSE;
213: return(0);
214: }
216: /* ugly stuff added for Glenn someday we should fix this up */
218: static PetscInt *auglyrmapd = 0,*auglyrmapo = 0; /* mapping from the local ordering to the "diagonal" and "off-diagonal" parts of the local matrix */
219: static Vec auglydd = 0,auglyoo = 0; /* work vectors used to scale the two parts of the local matrix */
222: PetscErrorCode MatMPIAIJDiagonalScaleLocalSetUp(Mat inA,Vec scale)
223: {
224: Mat_MPIAIJ *ina = (Mat_MPIAIJ*) inA->data; /*access private part of matrix */
226: PetscInt i,n,nt,cstart,cend,no,*garray = ina->garray,*lindices;
227: PetscInt *r_rmapd,*r_rmapo;
230: MatGetOwnershipRange(inA,&cstart,&cend);
231: MatGetSize(ina->A,NULL,&n);
232: PetscCalloc1(inA->rmap->mapping->n+1,&r_rmapd);
233: nt = 0;
234: for (i=0; i<inA->rmap->mapping->n; i++) {
235: if (inA->rmap->mapping->indices[i] >= cstart && inA->rmap->mapping->indices[i] < cend) {
236: nt++;
237: r_rmapd[i] = inA->rmap->mapping->indices[i] + 1;
238: }
239: }
240: if (nt != n) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_PLIB,"Hmm nt %D n %D",nt,n);
241: PetscMalloc1(n+1,&auglyrmapd);
242: for (i=0; i<inA->rmap->mapping->n; i++) {
243: if (r_rmapd[i]) {
244: auglyrmapd[(r_rmapd[i]-1)-cstart] = i;
245: }
246: }
247: PetscFree(r_rmapd);
248: VecCreateSeq(PETSC_COMM_SELF,n,&auglydd);
250: PetscCalloc1(inA->cmap->N+1,&lindices);
251: for (i=0; i<ina->B->cmap->n; i++) {
252: lindices[garray[i]] = i+1;
253: }
254: no = inA->rmap->mapping->n - nt;
255: PetscCalloc1(inA->rmap->mapping->n+1,&r_rmapo);
256: nt = 0;
257: for (i=0; i<inA->rmap->mapping->n; i++) {
258: if (lindices[inA->rmap->mapping->indices[i]]) {
259: nt++;
260: r_rmapo[i] = lindices[inA->rmap->mapping->indices[i]];
261: }
262: }
263: if (nt > no) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_PLIB,"Hmm nt %D no %D",nt,n);
264: PetscFree(lindices);
265: PetscMalloc1(nt+1,&auglyrmapo);
266: for (i=0; i<inA->rmap->mapping->n; i++) {
267: if (r_rmapo[i]) {
268: auglyrmapo[(r_rmapo[i]-1)] = i;
269: }
270: }
271: PetscFree(r_rmapo);
272: VecCreateSeq(PETSC_COMM_SELF,nt,&auglyoo);
273: return(0);
274: }
276: PetscErrorCode MatMPIAIJDiagonalScaleLocal(Mat A,Vec scale)
277: {
278: /* This routine should really be abandoned as it duplicates MatDiagonalScaleLocal */
282: PetscTryMethod(A,"MatDiagonalScaleLocal_C",(Mat,Vec),(A,scale));
283: return(0);
284: }
286: PetscErrorCode MatDiagonalScaleLocal_MPIAIJ(Mat A,Vec scale)
287: {
288: Mat_MPIAIJ *a = (Mat_MPIAIJ*) A->data; /*access private part of matrix */
289: PetscErrorCode ierr;
290: PetscInt n,i;
291: PetscScalar *d,*o;
292: const PetscScalar *s;
295: if (!auglyrmapd) {
296: MatMPIAIJDiagonalScaleLocalSetUp(A,scale);
297: }
299: VecGetArrayRead(scale,&s);
301: VecGetLocalSize(auglydd,&n);
302: VecGetArray(auglydd,&d);
303: for (i=0; i<n; i++) {
304: d[i] = s[auglyrmapd[i]]; /* copy "diagonal" (true local) portion of scale into dd vector */
305: }
306: VecRestoreArray(auglydd,&d);
307: /* column scale "diagonal" portion of local matrix */
308: MatDiagonalScale(a->A,NULL,auglydd);
310: VecGetLocalSize(auglyoo,&n);
311: VecGetArray(auglyoo,&o);
312: for (i=0; i<n; i++) {
313: o[i] = s[auglyrmapo[i]]; /* copy "off-diagonal" portion of scale into oo vector */
314: }
315: VecRestoreArrayRead(scale,&s);
316: VecRestoreArray(auglyoo,&o);
317: /* column scale "off-diagonal" portion of local matrix */
318: MatDiagonalScale(a->B,NULL,auglyoo);
319: return(0);
320: }