xref: /petsc/src/mat/impls/aij/mpi/crl/mcrl.c (revision bcaeba4d41d6ca6c6dc4189db20683073a9959ce)
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   if (aijcrl) {
29     ierr = PetscFree2(aijcrl->acols,aijcrl->icols);CHKERRQ(ierr);
30     ierr = VecDestroy(&aijcrl->fwork);CHKERRQ(ierr);
31     ierr = VecDestroy(&aijcrl->xwork);CHKERRQ(ierr);
32     ierr = PetscFree(aijcrl->array);CHKERRQ(ierr);
33   }
34   ierr = PetscFree(A->spptr);CHKERRQ(ierr);
35 
36   ierr = PetscObjectChangeTypeName( (PetscObject)A, MATMPIAIJ);CHKERRQ(ierr);
37   ierr = MatDestroy_MPIAIJ(A);CHKERRQ(ierr);
38   PetscFunctionReturn(0);
39 }
40 
41 #undef __FUNCT__
42 #define __FUNCT__ "MatMPIAIJCRL_create_aijcrl"
43 PetscErrorCode MatMPIAIJCRL_create_aijcrl(Mat A)
44 {
45   Mat_MPIAIJ     *a = (Mat_MPIAIJ *)(A)->data;
46   Mat_SeqAIJ     *Aij = (Mat_SeqAIJ*)(a->A->data), *Bij = (Mat_SeqAIJ*)(a->B->data);
47   Mat_AIJCRL     *aijcrl = (Mat_AIJCRL*) A->spptr;
48   PetscInt       m = A->rmap->n;  /* Number of rows in the matrix. */
49   PetscInt       nd = a->A->cmap->n; /* number of columns in diagonal portion */
50   PetscInt       *aj = Aij->j,*bj = Bij->j;  /* From the CSR representation; points to the beginning  of each row. */
51   PetscInt       i, j,rmax = 0,*icols, *ailen = Aij->ilen, *bilen = Bij->ilen;
52   PetscScalar    *aa = Aij->a,*ba = Bij->a,*acols,*array;
53   PetscErrorCode ierr;
54 
55   PetscFunctionBegin;
56   /* determine the row with the most columns */
57   for (i=0; i<m; i++) {
58     rmax = PetscMax(rmax,ailen[i]+bilen[i]);
59   }
60   aijcrl->nz   = Aij->nz+Bij->nz;
61   aijcrl->m    = A->rmap->n;
62   aijcrl->rmax = rmax;
63   ierr = PetscFree2(aijcrl->acols,aijcrl->icols);CHKERRQ(ierr);
64   ierr = PetscMalloc2(rmax*m,PetscScalar,&aijcrl->acols,rmax*m,PetscInt,&aijcrl->icols);CHKERRQ(ierr);
65   acols = aijcrl->acols;
66   icols = aijcrl->icols;
67   for (i=0; i<m; i++) {
68     for (j=0; j<ailen[i]; j++) {
69       acols[j*m+i] = *aa++;
70       icols[j*m+i] = *aj++;
71     }
72     for (;j<ailen[i]+bilen[i]; j++) {
73       acols[j*m+i] = *ba++;
74       icols[j*m+i] = nd + *bj++;
75     }
76     for (;j<rmax; j++) { /* empty column entries */
77       acols[j*m+i] = 0.0;
78       icols[j*m+i] = (j) ? icols[(j-1)*m+i] : 0;  /* handle case where row is EMPTY */
79     }
80   }
81   ierr = PetscInfo1(A,"Percentage of 0's introduced for vectorized multiply %g\n",1.0-((double)(aijcrl->nz))/((double)(rmax*m)));CHKERRQ(ierr);
82 
83   ierr = PetscFree(aijcrl->array);CHKERRQ(ierr);
84   ierr = PetscMalloc((a->B->cmap->n+nd)*sizeof(PetscScalar),&array);CHKERRQ(ierr);
85   /* xwork array is actually B->n+nd long, but we define xwork this length so can copy into it */
86   ierr = VecDestroy(&aijcrl->xwork);CHKERRQ(ierr);
87   ierr = VecCreateMPIWithArray(((PetscObject)A)->comm,1,nd,PETSC_DECIDE,array,&aijcrl->xwork);CHKERRQ(ierr);
88   ierr = VecDestroy(&aijcrl->fwork);CHKERRQ(ierr);
89   ierr = VecCreateSeqWithArray(PETSC_COMM_SELF,1,a->B->cmap->n,array+nd,&aijcrl->fwork);CHKERRQ(ierr);
90   aijcrl->array = array;
91   aijcrl->xscat = a->Mvctx;
92   PetscFunctionReturn(0);
93 }
94 
95 extern PetscErrorCode MatAssemblyEnd_MPIAIJ(Mat,MatAssemblyType);
96 
97 #undef __FUNCT__
98 #define __FUNCT__ "MatAssemblyEnd_MPIAIJCRL"
99 PetscErrorCode MatAssemblyEnd_MPIAIJCRL(Mat A, MatAssemblyType mode)
100 {
101   PetscErrorCode ierr;
102   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
103   Mat_SeqAIJ     *Aij = (Mat_SeqAIJ*)(a->A->data), *Bij = (Mat_SeqAIJ*)(a->A->data);
104 
105   PetscFunctionBegin;
106   Aij->inode.use = PETSC_FALSE;
107   Bij->inode.use = PETSC_FALSE;
108   ierr = MatAssemblyEnd_MPIAIJ(A,mode);CHKERRQ(ierr);
109   if (mode == MAT_FLUSH_ASSEMBLY) PetscFunctionReturn(0);
110 
111   /* Now calculate the permutation and grouping information. */
112   ierr = MatMPIAIJCRL_create_aijcrl(A);CHKERRQ(ierr);
113   PetscFunctionReturn(0);
114 }
115 
116 extern PetscErrorCode MatMult_AIJCRL(Mat,Vec,Vec);
117 extern PetscErrorCode MatDuplicate_AIJCRL(Mat,MatDuplicateOption,Mat*);
118 
119 /* MatConvert_MPIAIJ_MPIAIJCRL converts a MPIAIJ matrix into a
120  * MPIAIJCRL matrix.  This routine is called by the MatCreate_MPIAIJCRL()
121  * routine, but can also be used to convert an assembled MPIAIJ matrix
122  * into a MPIAIJCRL one. */
123 EXTERN_C_BEGIN
124 #undef __FUNCT__
125 #define __FUNCT__ "MatConvert_MPIAIJ_MPIAIJCRL"
126 PetscErrorCode  MatConvert_MPIAIJ_MPIAIJCRL(Mat A,MatType type,MatReuse reuse,Mat *newmat)
127 {
128   PetscErrorCode ierr;
129   Mat            B = *newmat;
130   Mat_AIJCRL     *aijcrl;
131 
132   PetscFunctionBegin;
133   if (reuse == MAT_INITIAL_MATRIX) {
134     ierr = MatDuplicate(A,MAT_COPY_VALUES,&B);CHKERRQ(ierr);
135   }
136 
137   ierr = PetscNewLog(B,Mat_AIJCRL,&aijcrl);CHKERRQ(ierr);
138   B->spptr = (void *) aijcrl;
139 
140   /* Set function pointers for methods that we inherit from AIJ but override. */
141   B->ops->duplicate   = MatDuplicate_AIJCRL;
142   B->ops->assemblyend = MatAssemblyEnd_MPIAIJCRL;
143   B->ops->destroy     = MatDestroy_MPIAIJCRL;
144   B->ops->mult        = MatMult_AIJCRL;
145 
146   /* If A has already been assembled, compute the permutation. */
147   if (A->assembled) {
148     ierr = MatMPIAIJCRL_create_aijcrl(B);CHKERRQ(ierr);
149   }
150   ierr = PetscObjectChangeTypeName((PetscObject)B,MATMPIAIJCRL);CHKERRQ(ierr);
151   *newmat = B;
152   PetscFunctionReturn(0);
153 }
154 EXTERN_C_END
155 
156 
157 #undef __FUNCT__
158 #define __FUNCT__ "MatCreateMPIAIJCRL"
159 /*@C
160    MatCreateMPIAIJCRL - Creates a sparse matrix of type MPIAIJCRL.
161    This type inherits from AIJ, but stores some additional
162    information that is used to allow better vectorization of
163    the matrix-vector product. At the cost of increased storage, the AIJ formatted
164    matrix can be copied to a format in which pieces of the matrix are
165    stored in ELLPACK format, allowing the vectorized matrix multiply
166    routine to use stride-1 memory accesses.  As with the AIJ type, it is
167    important to preallocate matrix storage in order to get good assembly
168    performance.
169 
170    Collective on MPI_Comm
171 
172    Input Parameters:
173 +  comm - MPI communicator, set to PETSC_COMM_SELF
174 .  m - number of rows
175 .  n - number of columns
176 .  nz - number of nonzeros per row (same for all rows)
177 -  nnz - array containing the number of nonzeros in the various rows
178          (possibly different for each row) or PETSC_NULL
179 
180    Output Parameter:
181 .  A - the matrix
182 
183    Notes:
184    If nnz is given then nz is ignored
185 
186    Level: intermediate
187 
188 .keywords: matrix, cray, sparse, parallel
189 
190 .seealso: MatCreate(), MatCreateMPIAIJPERM(), MatSetValues()
191 @*/
192 PetscErrorCode  MatCreateMPIAIJCRL(MPI_Comm comm,PetscInt m,PetscInt n,PetscInt nz,const PetscInt nnz[],PetscInt onz,const PetscInt onnz[],Mat *A)
193 {
194   PetscErrorCode ierr;
195 
196   PetscFunctionBegin;
197   ierr = MatCreate(comm,A);CHKERRQ(ierr);
198   ierr = MatSetSizes(*A,m,n,m,n);CHKERRQ(ierr);
199   ierr = MatSetType(*A,MATMPIAIJCRL);CHKERRQ(ierr);
200   ierr = MatMPIAIJSetPreallocation_MPIAIJ(*A,nz,(PetscInt*)nnz,onz,(PetscInt*)onnz);CHKERRQ(ierr);
201   PetscFunctionReturn(0);
202 }
203 
204 
205 EXTERN_C_BEGIN
206 #undef __FUNCT__
207 #define __FUNCT__ "MatCreate_MPIAIJCRL"
208 PetscErrorCode  MatCreate_MPIAIJCRL(Mat A)
209 {
210   PetscErrorCode ierr;
211 
212   PetscFunctionBegin;
213   ierr = MatSetType(A,MATMPIAIJ);CHKERRQ(ierr);
214   ierr = MatConvert_MPIAIJ_MPIAIJCRL(A,MATMPIAIJCRL,MAT_REUSE_MATRIX,&A);CHKERRQ(ierr);
215   PetscFunctionReturn(0);
216 }
217 EXTERN_C_END
218 
219