xref: /petsc/src/mat/impls/aij/mpi/crl/mcrl.c (revision 3c48a1e8da19189ff2402a4e41a2fc082d52c349)
1 
2 /*
3   Defines a matrix-vector product for the MATMPIAIJCRL matrix class.
4   This class is derived from the MATMPIAIJ class and retains the
5   compressed row storage (aka Yale sparse matrix format) but augments
6   it with a column oriented storage that is more efficient for
7   matrix vector products on Vector machines.
8 
9   CRL stands for constant row length (that is the same number of columns
10   is kept (padded with zeros) for each row of the sparse matrix.
11 
12    See src/mat/impls/aij/seq/crl/crl.c for the sequential version
13 */
14 
15 #include "../src/mat/impls/aij/mpi/mpiaij.h"
16 #include "../src/mat/impls/aij/seq/crl/crl.h"
17 
18 extern PetscErrorCode MatDestroy_MPIAIJ(Mat);
19 
20 #undef __FUNCT__
21 #define __FUNCT__ "MatDestroy_MPIAIJCRL"
22 PetscErrorCode MatDestroy_MPIAIJCRL(Mat A)
23 {
24   PetscErrorCode ierr;
25   Mat_AIJCRL     *aijcrl = (Mat_AIJCRL *) A->spptr;
26 
27   /* Free everything in the Mat_AIJCRL data structure. */
28   ierr = PetscFree2(aijcrl->acols,aijcrl->icols);CHKERRQ(ierr);
29   if (aijcrl->fwork) {
30     ierr = VecDestroy(aijcrl->fwork);CHKERRQ(ierr);
31   }
32   if (aijcrl->xwork) {
33     ierr = VecDestroy(aijcrl->xwork);CHKERRQ(ierr);
34   }
35   ierr = PetscFree(aijcrl->array);CHKERRQ(ierr);
36   ierr = PetscFree(A->spptr);CHKERRQ(ierr);
37 
38   ierr = PetscObjectChangeTypeName( (PetscObject)A, MATMPIAIJ);CHKERRQ(ierr);
39   ierr = MatDestroy_MPIAIJ(A);CHKERRQ(ierr);
40   PetscFunctionReturn(0);
41 }
42 
43 #undef __FUNCT__
44 #define __FUNCT__ "MPIAIJCRL_create_aijcrl"
45 PetscErrorCode MPIAIJCRL_create_aijcrl(Mat A)
46 {
47   Mat_MPIAIJ     *a = (Mat_MPIAIJ *)(A)->data;
48   Mat_SeqAIJ     *Aij = (Mat_SeqAIJ*)(a->A->data), *Bij = (Mat_SeqAIJ*)(a->B->data);
49   Mat_AIJCRL     *aijcrl = (Mat_AIJCRL*) A->spptr;
50   PetscInt       m = A->rmap->n;  /* Number of rows in the matrix. */
51   PetscInt       nd = a->A->cmap->n; /* number of columns in diagonal portion */
52   PetscInt       *aj = Aij->j,*bj = Bij->j;  /* From the CSR representation; points to the beginning  of each row. */
53   PetscInt       i, j,rmax = 0,*icols, *ailen = Aij->ilen, *bilen = Bij->ilen;
54   PetscScalar    *aa = Aij->a,*ba = Bij->a,*acols,*array;
55   PetscErrorCode ierr;
56 
57   PetscFunctionBegin;
58   /* determine the row with the most columns */
59   for (i=0; i<m; i++) {
60     rmax = PetscMax(rmax,ailen[i]+bilen[i]);
61   }
62   aijcrl->nz   = Aij->nz+Bij->nz;
63   aijcrl->m    = A->rmap->n;
64   aijcrl->rmax = rmax;
65   ierr = PetscFree2(aijcrl->acols,aijcrl->icols);CHKERRQ(ierr);
66   ierr = PetscMalloc2(rmax*m,PetscScalar,&aijcrl->acols,rmax*m,PetscInt,&aijcrl->icols);CHKERRQ(ierr);
67   acols = aijcrl->acols;
68   icols = aijcrl->icols;
69   for (i=0; i<m; i++) {
70     for (j=0; j<ailen[i]; j++) {
71       acols[j*m+i] = *aa++;
72       icols[j*m+i] = *aj++;
73     }
74     for (;j<ailen[i]+bilen[i]; j++) {
75       acols[j*m+i] = *ba++;
76       icols[j*m+i] = nd + *bj++;
77     }
78     for (;j<rmax; j++) { /* empty column entries */
79       acols[j*m+i] = 0.0;
80       icols[j*m+i] = (j) ? icols[(j-1)*m+i] : 0;  /* handle case where row is EMPTY */
81     }
82   }
83   ierr = PetscInfo1(A,"Percentage of 0's introduced for vectorized multiply %g\n",1.0-((double)(aijcrl->nz))/((double)(rmax*m)));
84 
85   ierr = PetscFree(aijcrl->array);CHKERRQ(ierr);
86   ierr = PetscMalloc((a->B->cmap->n+nd)*sizeof(PetscScalar),&array);CHKERRQ(ierr);
87   /* xwork array is actually B->n+nd long, but we define xwork this length so can copy into it */
88   if (aijcrl->xwork) {ierr = VecDestroy(aijcrl->xwork);CHKERRQ(ierr);}
89   ierr = VecCreateMPIWithArray(((PetscObject)A)->comm,nd,PETSC_DECIDE,array,&aijcrl->xwork);CHKERRQ(ierr);
90   if (aijcrl->fwork) {ierr = VecDestroy(aijcrl->fwork);CHKERRQ(ierr);}
91   ierr = VecCreateSeqWithArray(PETSC_COMM_SELF,a->B->cmap->n,array+nd,&aijcrl->fwork);CHKERRQ(ierr);
92   aijcrl->array = array;
93   aijcrl->xscat = a->Mvctx;
94   PetscFunctionReturn(0);
95 }
96 
97 extern PetscErrorCode MatAssemblyEnd_MPIAIJ(Mat,MatAssemblyType);
98 
99 #undef __FUNCT__
100 #define __FUNCT__ "MatAssemblyEnd_MPIAIJCRL"
101 PetscErrorCode MatAssemblyEnd_MPIAIJCRL(Mat A, MatAssemblyType mode)
102 {
103   PetscErrorCode ierr;
104   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
105   Mat_SeqAIJ     *Aij = (Mat_SeqAIJ*)(a->A->data), *Bij = (Mat_SeqAIJ*)(a->A->data);
106 
107   PetscFunctionBegin;
108   Aij->inode.use = PETSC_FALSE;
109   Bij->inode.use = PETSC_FALSE;
110   ierr = MatAssemblyEnd_MPIAIJ(A,mode);CHKERRQ(ierr);
111   if (mode == MAT_FLUSH_ASSEMBLY) PetscFunctionReturn(0);
112 
113   /* Now calculate the permutation and grouping information. */
114   ierr = MPIAIJCRL_create_aijcrl(A);CHKERRQ(ierr);
115   PetscFunctionReturn(0);
116 }
117 
118 extern PetscErrorCode MatMult_AIJCRL(Mat,Vec,Vec);
119 extern PetscErrorCode MatDuplicate_AIJCRL(Mat,MatDuplicateOption,Mat*);
120 
121 /* MatConvert_MPIAIJ_MPIAIJCRL converts a MPIAIJ matrix into a
122  * MPIAIJCRL matrix.  This routine is called by the MatCreate_MPIAIJCRL()
123  * routine, but can also be used to convert an assembled MPIAIJ matrix
124  * into a MPIAIJCRL one. */
125 EXTERN_C_BEGIN
126 #undef __FUNCT__
127 #define __FUNCT__ "MatConvert_MPIAIJ_MPIAIJCRL"
128 PetscErrorCode  MatConvert_MPIAIJ_MPIAIJCRL(Mat A,const MatType type,MatReuse reuse,Mat *newmat)
129 {
130   PetscErrorCode ierr;
131   Mat            B = *newmat;
132   Mat_AIJCRL     *aijcrl;
133 
134   PetscFunctionBegin;
135   if (reuse == MAT_INITIAL_MATRIX) {
136     ierr = MatDuplicate(A,MAT_COPY_VALUES,&B);CHKERRQ(ierr);
137   }
138 
139   ierr = PetscNewLog(B,Mat_AIJCRL,&aijcrl);CHKERRQ(ierr);
140   B->spptr = (void *) aijcrl;
141 
142   /* Set function pointers for methods that we inherit from AIJ but override. */
143   B->ops->duplicate   = MatDuplicate_AIJCRL;
144   B->ops->assemblyend = MatAssemblyEnd_MPIAIJCRL;
145   B->ops->destroy     = MatDestroy_MPIAIJCRL;
146   B->ops->mult        = MatMult_AIJCRL;
147 
148   /* If A has already been assembled, compute the permutation. */
149   if (A->assembled) {
150     ierr = MPIAIJCRL_create_aijcrl(B);CHKERRQ(ierr);
151   }
152   ierr = PetscObjectChangeTypeName((PetscObject)B,MATMPIAIJCRL);CHKERRQ(ierr);
153   *newmat = B;
154   PetscFunctionReturn(0);
155 }
156 EXTERN_C_END
157 
158 
159 #undef __FUNCT__
160 #define __FUNCT__ "MatCreateMPIAIJCRL"
161 /*@C
162    MatCreateMPIAIJCRL - Creates a sparse matrix of type MPIAIJCRL.
163    This type inherits from AIJ, but stores some additional
164    information that is used to allow better vectorization of
165    the matrix-vector product. At the cost of increased storage, the AIJ formatted
166    matrix can be copied to a format in which pieces of the matrix are
167    stored in ELLPACK format, allowing the vectorized matrix multiply
168    routine to use stride-1 memory accesses.  As with the AIJ type, it is
169    important to preallocate matrix storage in order to get good assembly
170    performance.
171 
172    Collective on MPI_Comm
173 
174    Input Parameters:
175 +  comm - MPI communicator, set to PETSC_COMM_SELF
176 .  m - number of rows
177 .  n - number of columns
178 .  nz - number of nonzeros per row (same for all rows)
179 -  nnz - array containing the number of nonzeros in the various rows
180          (possibly different for each row) or PETSC_NULL
181 
182    Output Parameter:
183 .  A - the matrix
184 
185    Notes:
186    If nnz is given then nz is ignored
187 
188    Level: intermediate
189 
190 .keywords: matrix, cray, sparse, parallel
191 
192 .seealso: MatCreate(), MatCreateMPIAIJPERM(), MatSetValues()
193 @*/
194 PetscErrorCode  MatCreateMPIAIJCRL(MPI_Comm comm,PetscInt m,PetscInt n,PetscInt nz,const PetscInt nnz[],PetscInt onz,const PetscInt onnz[],Mat *A)
195 {
196   PetscErrorCode ierr;
197 
198   PetscFunctionBegin;
199   ierr = MatCreate(comm,A);CHKERRQ(ierr);
200   ierr = MatSetSizes(*A,m,n,m,n);CHKERRQ(ierr);
201   ierr = MatSetType(*A,MATMPIAIJCRL);CHKERRQ(ierr);
202   ierr = MatMPIAIJSetPreallocation_MPIAIJ(*A,nz,(PetscInt*)nnz,onz,(PetscInt*)onnz);CHKERRQ(ierr);
203   PetscFunctionReturn(0);
204 }
205 
206 
207 EXTERN_C_BEGIN
208 #undef __FUNCT__
209 #define __FUNCT__ "MatCreate_MPIAIJCRL"
210 PetscErrorCode  MatCreate_MPIAIJCRL(Mat A)
211 {
212   PetscErrorCode ierr;
213 
214   PetscFunctionBegin;
215   ierr = MatSetType(A,MATMPIAIJ);CHKERRQ(ierr);
216   ierr = MatConvert_MPIAIJ_MPIAIJCRL(A,MATMPIAIJCRL,MAT_REUSE_MATRIX,&A);CHKERRQ(ierr);
217   PetscFunctionReturn(0);
218 }
219 EXTERN_C_END
220 
221