xref: /petsc/src/mat/impls/aij/mpi/crl/mcrl.c (revision bebe2cf65d55febe21a5af8db2bd2e168caaa2e7)
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 
64   ierr  = PetscFree2(aijcrl->acols,aijcrl->icols);CHKERRQ(ierr);
65   ierr  = PetscMalloc2(rmax*m,&aijcrl->acols,rmax*m,&aijcrl->icols);CHKERRQ(ierr);
66   acols = aijcrl->acols;
67   icols = aijcrl->icols;
68   for (i=0; i<m; i++) {
69     for (j=0; j<ailen[i]; j++) {
70       acols[j*m+i] = *aa++;
71       icols[j*m+i] = *aj++;
72     }
73     for (; j<ailen[i]+bilen[i]; j++) {
74       acols[j*m+i] = *ba++;
75       icols[j*m+i] = nd + *bj++;
76     }
77     for (; j<rmax; j++) { /* empty column entries */
78       acols[j*m+i] = 0.0;
79       icols[j*m+i] = (j) ? icols[(j-1)*m+i] : 0;  /* handle case where row is EMPTY */
80     }
81   }
82   ierr = PetscInfo1(A,"Percentage of 0's introduced for vectorized multiply %g\n",1.0-((double)(aijcrl->nz))/((double)(rmax*m)));CHKERRQ(ierr);
83 
84   ierr = PetscFree(aijcrl->array);CHKERRQ(ierr);
85   ierr = PetscMalloc1(a->B->cmap->n+nd,&array);CHKERRQ(ierr);
86   /* xwork array is actually B->n+nd long, but we define xwork this length so can copy into it */
87   ierr = VecDestroy(&aijcrl->xwork);CHKERRQ(ierr);
88   ierr = VecCreateMPIWithArray(PetscObjectComm((PetscObject)A),1,nd,PETSC_DECIDE,array,&aijcrl->xwork);CHKERRQ(ierr);
89   ierr = VecDestroy(&aijcrl->fwork);CHKERRQ(ierr);
90   ierr = VecCreateSeqWithArray(PETSC_COMM_SELF,1,a->B->cmap->n,array+nd,&aijcrl->fwork);CHKERRQ(ierr);
91 
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 
111   ierr = MatAssemblyEnd_MPIAIJ(A,mode);CHKERRQ(ierr);
112   if (mode == MAT_FLUSH_ASSEMBLY) PetscFunctionReturn(0);
113 
114   /* Now calculate the permutation and grouping information. */
115   ierr = MatMPIAIJCRL_create_aijcrl(A);CHKERRQ(ierr);
116   PetscFunctionReturn(0);
117 }
118 
119 extern PetscErrorCode MatMult_AIJCRL(Mat,Vec,Vec);
120 extern PetscErrorCode MatDuplicate_AIJCRL(Mat,MatDuplicateOption,Mat*);
121 
122 /* MatConvert_MPIAIJ_MPIAIJCRL converts a MPIAIJ matrix into a
123  * MPIAIJCRL matrix.  This routine is called by the MatCreate_MPIAIJCRL()
124  * routine, but can also be used to convert an assembled MPIAIJ matrix
125  * into a MPIAIJCRL one. */
126 
127 #undef __FUNCT__
128 #define __FUNCT__ "MatConvert_MPIAIJ_MPIAIJCRL"
129 PETSC_EXTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJCRL(Mat A,MatType type,MatReuse reuse,Mat *newmat)
130 {
131   PetscErrorCode ierr;
132   Mat            B = *newmat;
133   Mat_AIJCRL     *aijcrl;
134 
135   PetscFunctionBegin;
136   if (reuse == MAT_INITIAL_MATRIX) {
137     ierr = MatDuplicate(A,MAT_COPY_VALUES,&B);CHKERRQ(ierr);
138   }
139 
140   ierr     = PetscNewLog(B,&aijcrl);CHKERRQ(ierr);
141   B->spptr = (void*) aijcrl;
142 
143   /* Set function pointers for methods that we inherit from AIJ but override. */
144   B->ops->duplicate   = MatDuplicate_AIJCRL;
145   B->ops->assemblyend = MatAssemblyEnd_MPIAIJCRL;
146   B->ops->destroy     = MatDestroy_MPIAIJCRL;
147   B->ops->mult        = MatMult_AIJCRL;
148 
149   /* If A has already been assembled, compute the permutation. */
150   if (A->assembled) {
151     ierr = MatMPIAIJCRL_create_aijcrl(B);CHKERRQ(ierr);
152   }
153   ierr    = PetscObjectChangeTypeName((PetscObject)B,MATMPIAIJCRL);CHKERRQ(ierr);
154   *newmat = B;
155   PetscFunctionReturn(0);
156 }
157 
158 #undef __FUNCT__
159 #define __FUNCT__ "MatCreateMPIAIJCRL"
160 /*@C
161    MatCreateMPIAIJCRL - Creates a sparse matrix of type MPIAIJCRL.
162    This type inherits from AIJ, but stores some additional
163    information that is used to allow better vectorization of
164    the matrix-vector product. At the cost of increased storage, the AIJ formatted
165    matrix can be copied to a format in which pieces of the matrix are
166    stored in ELLPACK format, allowing the vectorized matrix multiply
167    routine to use stride-1 memory accesses.  As with the AIJ type, it is
168    important to preallocate matrix storage in order to get good assembly
169    performance.
170 
171    Collective on MPI_Comm
172 
173    Input Parameters:
174 +  comm - MPI communicator, set to PETSC_COMM_SELF
175 .  m - number of rows
176 .  n - number of columns
177 .  nz - number of nonzeros per row (same for all rows)
178 -  nnz - array containing the number of nonzeros in the various rows
179          (possibly different for each row) or NULL
180 
181    Output Parameter:
182 .  A - the matrix
183 
184    Notes:
185    If nnz is given then nz is ignored
186 
187    Level: intermediate
188 
189 .keywords: matrix, cray, sparse, parallel
190 
191 .seealso: MatCreate(), MatCreateMPIAIJPERM(), MatSetValues()
192 @*/
193 PetscErrorCode  MatCreateMPIAIJCRL(MPI_Comm comm,PetscInt m,PetscInt n,PetscInt nz,const PetscInt nnz[],PetscInt onz,const PetscInt onnz[],Mat *A)
194 {
195   PetscErrorCode ierr;
196 
197   PetscFunctionBegin;
198   ierr = MatCreate(comm,A);CHKERRQ(ierr);
199   ierr = MatSetSizes(*A,m,n,m,n);CHKERRQ(ierr);
200   ierr = MatSetType(*A,MATMPIAIJCRL);CHKERRQ(ierr);
201   ierr = MatMPIAIJSetPreallocation_MPIAIJ(*A,nz,(PetscInt*)nnz,onz,(PetscInt*)onnz);CHKERRQ(ierr);
202   PetscFunctionReturn(0);
203 }
204 
205 #undef __FUNCT__
206 #define __FUNCT__ "MatCreate_MPIAIJCRL"
207 PETSC_EXTERN PetscErrorCode MatCreate_MPIAIJCRL(Mat A)
208 {
209   PetscErrorCode ierr;
210 
211   PetscFunctionBegin;
212   ierr = MatSetType(A,MATMPIAIJ);CHKERRQ(ierr);
213   ierr = MatConvert_MPIAIJ_MPIAIJCRL(A,MATMPIAIJCRL,MAT_REUSE_MATRIX,&A);CHKERRQ(ierr);
214   PetscFunctionReturn(0);
215 }
216 
217