xref: /petsc/src/mat/impls/aij/mpi/crl/mcrl.c (revision d155d4104c12796cc6e93a7e2b3cd74e97fcda36)
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   ierr = VecDestroy(&aijcrl->fwork);CHKERRQ(ierr);
30   ierr = VecDestroy(&aijcrl->xwork);CHKERRQ(ierr);
31   ierr = PetscFree(aijcrl->array);CHKERRQ(ierr);
32   ierr = PetscFree(A->spptr);CHKERRQ(ierr);
33 
34   ierr = PetscObjectChangeTypeName( (PetscObject)A, MATMPIAIJ);CHKERRQ(ierr);
35   ierr = MatDestroy_MPIAIJ(A);CHKERRQ(ierr);
36   PetscFunctionReturn(0);
37 }
38 
39 #undef __FUNCT__
40 #define __FUNCT__ "MPIAIJCRL_create_aijcrl"
41 PetscErrorCode MPIAIJCRL_create_aijcrl(Mat A)
42 {
43   Mat_MPIAIJ     *a = (Mat_MPIAIJ *)(A)->data;
44   Mat_SeqAIJ     *Aij = (Mat_SeqAIJ*)(a->A->data), *Bij = (Mat_SeqAIJ*)(a->B->data);
45   Mat_AIJCRL     *aijcrl = (Mat_AIJCRL*) A->spptr;
46   PetscInt       m = A->rmap->n;  /* Number of rows in the matrix. */
47   PetscInt       nd = a->A->cmap->n; /* number of columns in diagonal portion */
48   PetscInt       *aj = Aij->j,*bj = Bij->j;  /* From the CSR representation; points to the beginning  of each row. */
49   PetscInt       i, j,rmax = 0,*icols, *ailen = Aij->ilen, *bilen = Bij->ilen;
50   PetscScalar    *aa = Aij->a,*ba = Bij->a,*acols,*array;
51   PetscErrorCode ierr;
52 
53   PetscFunctionBegin;
54   /* determine the row with the most columns */
55   for (i=0; i<m; i++) {
56     rmax = PetscMax(rmax,ailen[i]+bilen[i]);
57   }
58   aijcrl->nz   = Aij->nz+Bij->nz;
59   aijcrl->m    = A->rmap->n;
60   aijcrl->rmax = rmax;
61   ierr = PetscFree2(aijcrl->acols,aijcrl->icols);CHKERRQ(ierr);
62   ierr = PetscMalloc2(rmax*m,PetscScalar,&aijcrl->acols,rmax*m,PetscInt,&aijcrl->icols);CHKERRQ(ierr);
63   acols = aijcrl->acols;
64   icols = aijcrl->icols;
65   for (i=0; i<m; i++) {
66     for (j=0; j<ailen[i]; j++) {
67       acols[j*m+i] = *aa++;
68       icols[j*m+i] = *aj++;
69     }
70     for (;j<ailen[i]+bilen[i]; j++) {
71       acols[j*m+i] = *ba++;
72       icols[j*m+i] = nd + *bj++;
73     }
74     for (;j<rmax; j++) { /* empty column entries */
75       acols[j*m+i] = 0.0;
76       icols[j*m+i] = (j) ? icols[(j-1)*m+i] : 0;  /* handle case where row is EMPTY */
77     }
78   }
79   ierr = PetscInfo1(A,"Percentage of 0's introduced for vectorized multiply %g\n",1.0-((double)(aijcrl->nz))/((double)(rmax*m)));
80 
81   ierr = PetscFree(aijcrl->array);CHKERRQ(ierr);
82   ierr = PetscMalloc((a->B->cmap->n+nd)*sizeof(PetscScalar),&array);CHKERRQ(ierr);
83   /* xwork array is actually B->n+nd long, but we define xwork this length so can copy into it */
84   ierr = VecDestroy(&aijcrl->xwork);CHKERRQ(ierr);
85   ierr = VecCreateMPIWithArray(((PetscObject)A)->comm,nd,PETSC_DECIDE,array,&aijcrl->xwork);CHKERRQ(ierr);
86   ierr = VecDestroy(&aijcrl->fwork);CHKERRQ(ierr);
87   ierr = VecCreateSeqWithArray(PETSC_COMM_SELF,a->B->cmap->n,array+nd,&aijcrl->fwork);CHKERRQ(ierr);
88   aijcrl->array = array;
89   aijcrl->xscat = a->Mvctx;
90   PetscFunctionReturn(0);
91 }
92 
93 extern PetscErrorCode MatAssemblyEnd_MPIAIJ(Mat,MatAssemblyType);
94 
95 #undef __FUNCT__
96 #define __FUNCT__ "MatAssemblyEnd_MPIAIJCRL"
97 PetscErrorCode MatAssemblyEnd_MPIAIJCRL(Mat A, MatAssemblyType mode)
98 {
99   PetscErrorCode ierr;
100   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
101   Mat_SeqAIJ     *Aij = (Mat_SeqAIJ*)(a->A->data), *Bij = (Mat_SeqAIJ*)(a->A->data);
102 
103   PetscFunctionBegin;
104   Aij->inode.use = PETSC_FALSE;
105   Bij->inode.use = PETSC_FALSE;
106   ierr = MatAssemblyEnd_MPIAIJ(A,mode);CHKERRQ(ierr);
107   if (mode == MAT_FLUSH_ASSEMBLY) PetscFunctionReturn(0);
108 
109   /* Now calculate the permutation and grouping information. */
110   ierr = MPIAIJCRL_create_aijcrl(A);CHKERRQ(ierr);
111   PetscFunctionReturn(0);
112 }
113 
114 extern PetscErrorCode MatMult_AIJCRL(Mat,Vec,Vec);
115 extern PetscErrorCode MatDuplicate_AIJCRL(Mat,MatDuplicateOption,Mat*);
116 
117 /* MatConvert_MPIAIJ_MPIAIJCRL converts a MPIAIJ matrix into a
118  * MPIAIJCRL matrix.  This routine is called by the MatCreate_MPIAIJCRL()
119  * routine, but can also be used to convert an assembled MPIAIJ matrix
120  * into a MPIAIJCRL one. */
121 EXTERN_C_BEGIN
122 #undef __FUNCT__
123 #define __FUNCT__ "MatConvert_MPIAIJ_MPIAIJCRL"
124 PetscErrorCode  MatConvert_MPIAIJ_MPIAIJCRL(Mat A,const MatType type,MatReuse reuse,Mat *newmat)
125 {
126   PetscErrorCode ierr;
127   Mat            B = *newmat;
128   Mat_AIJCRL     *aijcrl;
129 
130   PetscFunctionBegin;
131   if (reuse == MAT_INITIAL_MATRIX) {
132     ierr = MatDuplicate(A,MAT_COPY_VALUES,&B);CHKERRQ(ierr);
133   }
134 
135   ierr = PetscNewLog(B,Mat_AIJCRL,&aijcrl);CHKERRQ(ierr);
136   B->spptr = (void *) aijcrl;
137 
138   /* Set function pointers for methods that we inherit from AIJ but override. */
139   B->ops->duplicate   = MatDuplicate_AIJCRL;
140   B->ops->assemblyend = MatAssemblyEnd_MPIAIJCRL;
141   B->ops->destroy     = MatDestroy_MPIAIJCRL;
142   B->ops->mult        = MatMult_AIJCRL;
143 
144   /* If A has already been assembled, compute the permutation. */
145   if (A->assembled) {
146     ierr = MPIAIJCRL_create_aijcrl(B);CHKERRQ(ierr);
147   }
148   ierr = PetscObjectChangeTypeName((PetscObject)B,MATMPIAIJCRL);CHKERRQ(ierr);
149   *newmat = B;
150   PetscFunctionReturn(0);
151 }
152 EXTERN_C_END
153 
154 
155 #undef __FUNCT__
156 #define __FUNCT__ "MatCreateMPIAIJCRL"
157 /*@C
158    MatCreateMPIAIJCRL - Creates a sparse matrix of type MPIAIJCRL.
159    This type inherits from AIJ, but stores some additional
160    information that is used to allow better vectorization of
161    the matrix-vector product. At the cost of increased storage, the AIJ formatted
162    matrix can be copied to a format in which pieces of the matrix are
163    stored in ELLPACK format, allowing the vectorized matrix multiply
164    routine to use stride-1 memory accesses.  As with the AIJ type, it is
165    important to preallocate matrix storage in order to get good assembly
166    performance.
167 
168    Collective on MPI_Comm
169 
170    Input Parameters:
171 +  comm - MPI communicator, set to PETSC_COMM_SELF
172 .  m - number of rows
173 .  n - number of columns
174 .  nz - number of nonzeros per row (same for all rows)
175 -  nnz - array containing the number of nonzeros in the various rows
176          (possibly different for each row) or PETSC_NULL
177 
178    Output Parameter:
179 .  A - the matrix
180 
181    Notes:
182    If nnz is given then nz is ignored
183 
184    Level: intermediate
185 
186 .keywords: matrix, cray, sparse, parallel
187 
188 .seealso: MatCreate(), MatCreateMPIAIJPERM(), MatSetValues()
189 @*/
190 PetscErrorCode  MatCreateMPIAIJCRL(MPI_Comm comm,PetscInt m,PetscInt n,PetscInt nz,const PetscInt nnz[],PetscInt onz,const PetscInt onnz[],Mat *A)
191 {
192   PetscErrorCode ierr;
193 
194   PetscFunctionBegin;
195   ierr = MatCreate(comm,A);CHKERRQ(ierr);
196   ierr = MatSetSizes(*A,m,n,m,n);CHKERRQ(ierr);
197   ierr = MatSetType(*A,MATMPIAIJCRL);CHKERRQ(ierr);
198   ierr = MatMPIAIJSetPreallocation_MPIAIJ(*A,nz,(PetscInt*)nnz,onz,(PetscInt*)onnz);CHKERRQ(ierr);
199   PetscFunctionReturn(0);
200 }
201 
202 
203 EXTERN_C_BEGIN
204 #undef __FUNCT__
205 #define __FUNCT__ "MatCreate_MPIAIJCRL"
206 PetscErrorCode  MatCreate_MPIAIJCRL(Mat A)
207 {
208   PetscErrorCode ierr;
209 
210   PetscFunctionBegin;
211   ierr = MatSetType(A,MATMPIAIJ);CHKERRQ(ierr);
212   ierr = MatConvert_MPIAIJ_MPIAIJCRL(A,MATMPIAIJCRL,MAT_REUSE_MATRIX,&A);CHKERRQ(ierr);
213   PetscFunctionReturn(0);
214 }
215 EXTERN_C_END
216 
217