xref: /petsc/src/ksp/pc/impls/pbjacobi/pbjacobi.c (revision d45987f3cb8da7dca4e7c09f0fedfc3d8f6afad7)
1 
2 /*
3    Include files needed for the PBJacobi preconditioner:
4      pcimpl.h - private include file intended for use by all preconditioners
5 */
6 
7 #include <petsc-private/matimpl.h>
8 #include <petsc-private/pcimpl.h>   /*I "petscpc.h" I*/
9 
10 /*
11    Private context (data structure) for the PBJacobi preconditioner.
12 */
13 typedef struct {
14   const MatScalar *diag;
15   PetscInt    bs,mbs;
16 } PC_PBJacobi;
17 
18 
19 #undef __FUNCT__
20 #define __FUNCT__ "PCApply_PBJacobi_1"
21 static PetscErrorCode PCApply_PBJacobi_1(PC pc,Vec x,Vec y)
22 {
23   PC_PBJacobi       *jac = (PC_PBJacobi*)pc->data;
24   PetscErrorCode    ierr;
25   PetscInt          i,m = jac->mbs;
26   const MatScalar   *diag = jac->diag;
27   const PetscScalar *xx;
28   PetscScalar       *yy;
29 
30   PetscFunctionBegin;
31   ierr = VecGetArrayRead(x,&xx);CHKERRQ(ierr);
32   ierr = VecGetArray(y,&yy);CHKERRQ(ierr);
33   for (i=0; i<m; i++) {
34     yy[i] = diag[i]*xx[i];
35   }
36   ierr = VecRestoreArrayRead(x,&xx);CHKERRQ(ierr);
37   ierr = VecRestoreArray(y,&yy);CHKERRQ(ierr);
38   ierr = PetscLogFlops(2.0*m);CHKERRQ(ierr);
39   PetscFunctionReturn(0);
40 }
41 
42 #undef __FUNCT__
43 #define __FUNCT__ "PCApply_PBJacobi_2"
44 static PetscErrorCode PCApply_PBJacobi_2(PC pc,Vec x,Vec y)
45 {
46   PC_PBJacobi     *jac = (PC_PBJacobi*)pc->data;
47   PetscErrorCode  ierr;
48   PetscInt        i,m = jac->mbs;
49   const MatScalar *diag = jac->diag;
50   PetscScalar     x0,x1,*xx,*yy;
51 
52   PetscFunctionBegin;
53   ierr = VecGetArray(x,&xx);CHKERRQ(ierr);
54   ierr = VecGetArray(y,&yy);CHKERRQ(ierr);
55   for (i=0; i<m; i++) {
56     x0 = xx[2*i]; x1 = xx[2*i+1];
57     yy[2*i]   = diag[0]*x0 + diag[2]*x1;
58     yy[2*i+1] = diag[1]*x0 + diag[3]*x1;
59     diag     += 4;
60   }
61   ierr = VecRestoreArray(x,&xx);CHKERRQ(ierr);
62   ierr = VecRestoreArray(y,&yy);CHKERRQ(ierr);
63   ierr = PetscLogFlops(6.0*m);CHKERRQ(ierr);
64   PetscFunctionReturn(0);
65 }
66 #undef __FUNCT__
67 #define __FUNCT__ "PCApply_PBJacobi_3"
68 static PetscErrorCode PCApply_PBJacobi_3(PC pc,Vec x,Vec y)
69 {
70   PC_PBJacobi     *jac = (PC_PBJacobi*)pc->data;
71   PetscErrorCode  ierr;
72   PetscInt        i,m = jac->mbs;
73   const MatScalar *diag = jac->diag;
74   PetscScalar     x0,x1,x2,*xx,*yy;
75 
76   PetscFunctionBegin;
77   ierr = VecGetArray(x,&xx);CHKERRQ(ierr);
78   ierr = VecGetArray(y,&yy);CHKERRQ(ierr);
79   for (i=0; i<m; i++) {
80     x0 = xx[3*i]; x1 = xx[3*i+1]; x2 = xx[3*i+2];
81     yy[3*i]   = diag[0]*x0 + diag[3]*x1 + diag[6]*x2;
82     yy[3*i+1] = diag[1]*x0 + diag[4]*x1 + diag[7]*x2;
83     yy[3*i+2] = diag[2]*x0 + diag[5]*x1 + diag[8]*x2;
84     diag     += 9;
85   }
86   ierr = VecRestoreArray(x,&xx);CHKERRQ(ierr);
87   ierr = VecRestoreArray(y,&yy);CHKERRQ(ierr);
88   ierr = PetscLogFlops(15.0*m);CHKERRQ(ierr);
89   PetscFunctionReturn(0);
90 }
91 #undef __FUNCT__
92 #define __FUNCT__ "PCApply_PBJacobi_4"
93 static PetscErrorCode PCApply_PBJacobi_4(PC pc,Vec x,Vec y)
94 {
95   PC_PBJacobi      *jac = (PC_PBJacobi*)pc->data;
96   PetscErrorCode   ierr;
97   PetscInt         i,m = jac->mbs;
98   const MatScalar  *diag = jac->diag;
99   PetscScalar      x0,x1,x2,x3,*xx,*yy;
100 
101   PetscFunctionBegin;
102   ierr = VecGetArray(x,&xx);CHKERRQ(ierr);
103   ierr = VecGetArray(y,&yy);CHKERRQ(ierr);
104   for (i=0; i<m; i++) {
105     x0 = xx[4*i]; x1 = xx[4*i+1]; x2 = xx[4*i+2]; x3 = xx[4*i+3];
106     yy[4*i]   = diag[0]*x0 + diag[4]*x1 + diag[8]*x2  + diag[12]*x3;
107     yy[4*i+1] = diag[1]*x0 + diag[5]*x1 + diag[9]*x2  + diag[13]*x3;
108     yy[4*i+2] = diag[2]*x0 + diag[6]*x1 + diag[10]*x2 + diag[14]*x3;
109     yy[4*i+3] = diag[3]*x0 + diag[7]*x1 + diag[11]*x2 + diag[15]*x3;
110     diag     += 16;
111   }
112   ierr = VecRestoreArray(x,&xx);CHKERRQ(ierr);
113   ierr = VecRestoreArray(y,&yy);CHKERRQ(ierr);
114   ierr = PetscLogFlops(28.0*m);CHKERRQ(ierr);
115   PetscFunctionReturn(0);
116 }
117 #undef __FUNCT__
118 #define __FUNCT__ "PCApply_PBJacobi_5"
119 static PetscErrorCode PCApply_PBJacobi_5(PC pc,Vec x,Vec y)
120 {
121   PC_PBJacobi     *jac = (PC_PBJacobi*)pc->data;
122   PetscErrorCode  ierr;
123   PetscInt        i,m = jac->mbs;
124   const MatScalar *diag = jac->diag;
125   PetscScalar     x0,x1,x2,x3,x4,*xx,*yy;
126 
127   PetscFunctionBegin;
128   ierr = VecGetArray(x,&xx);CHKERRQ(ierr);
129   ierr = VecGetArray(y,&yy);CHKERRQ(ierr);
130   for (i=0; i<m; i++) {
131     x0 = xx[5*i]; x1 = xx[5*i+1]; x2 = xx[5*i+2]; x3 = xx[5*i+3]; x4 = xx[5*i+4];
132     yy[5*i]   = diag[0]*x0 + diag[5]*x1 + diag[10]*x2  + diag[15]*x3 + diag[20]*x4;
133     yy[5*i+1] = diag[1]*x0 + diag[6]*x1 + diag[11]*x2  + diag[16]*x3 + diag[21]*x4;
134     yy[5*i+2] = diag[2]*x0 + diag[7]*x1 + diag[12]*x2 + diag[17]*x3 + diag[22]*x4;
135     yy[5*i+3] = diag[3]*x0 + diag[8]*x1 + diag[13]*x2 + diag[18]*x3 + diag[23]*x4;
136     yy[5*i+4] = diag[4]*x0 + diag[9]*x1 + diag[14]*x2 + diag[19]*x3 + diag[24]*x4;
137     diag     += 25;
138   }
139   ierr = VecRestoreArray(x,&xx);CHKERRQ(ierr);
140   ierr = VecRestoreArray(y,&yy);CHKERRQ(ierr);
141   ierr = PetscLogFlops(45.0*m);CHKERRQ(ierr);
142   PetscFunctionReturn(0);
143 }
144 #undef __FUNCT__
145 #define __FUNCT__ "PCApply_PBJacobi_6"
146 static PetscErrorCode PCApply_PBJacobi_6(PC pc,Vec x,Vec y)
147 {
148   PC_PBJacobi     *jac = (PC_PBJacobi*)pc->data;
149   PetscErrorCode  ierr;
150   PetscInt        i,m = jac->mbs;
151   const MatScalar *diag = jac->diag;
152   PetscScalar     x0,x1,x2,x3,x4,x5,*xx,*yy;
153 
154   PetscFunctionBegin;
155   ierr = VecGetArray(x,&xx);CHKERRQ(ierr);
156   ierr = VecGetArray(y,&yy);CHKERRQ(ierr);
157   for (i=0; i<m; i++) {
158     x0 = xx[6*i]; x1 = xx[6*i+1]; x2 = xx[6*i+2]; x3 = xx[6*i+3]; x4 = xx[6*i+4]; x5 = xx[6*i+5];
159     yy[6*i]   = diag[0]*x0 + diag[6]*x1  + diag[12]*x2  + diag[18]*x3 + diag[24]*x4 + diag[30]*x5;
160     yy[6*i+1] = diag[1]*x0 + diag[7]*x1  + diag[13]*x2  + diag[19]*x3 + diag[25]*x4 + diag[31]*x5;
161     yy[6*i+2] = diag[2]*x0 + diag[8]*x1  + diag[14]*x2  + diag[20]*x3 + diag[26]*x4 + diag[32]*x5;
162     yy[6*i+3] = diag[3]*x0 + diag[9]*x1  + diag[15]*x2  + diag[21]*x3 + diag[27]*x4 + diag[33]*x5;
163     yy[6*i+4] = diag[4]*x0 + diag[10]*x1 + diag[16]*x2  + diag[22]*x3 + diag[28]*x4 + diag[34]*x5;
164     yy[6*i+5] = diag[5]*x0 + diag[11]*x1 + diag[17]*x2  + diag[23]*x3 + diag[29]*x4 + diag[35]*x5;
165     diag     += 36;
166   }
167   ierr = VecRestoreArray(x,&xx);CHKERRQ(ierr);
168   ierr = VecRestoreArray(y,&yy);CHKERRQ(ierr);
169   ierr = PetscLogFlops(66.0*m);CHKERRQ(ierr);
170   PetscFunctionReturn(0);
171 }
172 #undef __FUNCT__
173 #define __FUNCT__ "PCApply_PBJacobi_7"
174 static PetscErrorCode PCApply_PBJacobi_7(PC pc,Vec x,Vec y)
175 {
176   PC_PBJacobi     *jac = (PC_PBJacobi*)pc->data;
177   PetscErrorCode  ierr;
178   PetscInt        i,m = jac->mbs;
179   const MatScalar *diag = jac->diag;
180   PetscScalar     x0,x1,x2,x3,x4,x5,x6,*xx,*yy;
181 
182   PetscFunctionBegin;
183   ierr = VecGetArray(x,&xx);CHKERRQ(ierr);
184   ierr = VecGetArray(y,&yy);CHKERRQ(ierr);
185   for (i=0; i<m; i++) {
186     x0 = xx[7*i]; x1 = xx[7*i+1]; x2 = xx[7*i+2]; x3 = xx[7*i+3]; x4 = xx[7*i+4]; x5 = xx[7*i+5]; x6 = xx[7*i+6];
187     yy[7*i]   = diag[0]*x0 + diag[7]*x1  + diag[14]*x2  + diag[21]*x3 + diag[28]*x4 + diag[35]*x5 + diag[42]*x6;
188     yy[7*i+1] = diag[1]*x0 + diag[8]*x1  + diag[15]*x2  + diag[22]*x3 + diag[29]*x4 + diag[36]*x5 + diag[43]*x6;
189     yy[7*i+2] = diag[2]*x0 + diag[9]*x1  + diag[16]*x2  + diag[23]*x3 + diag[30]*x4 + diag[37]*x5 + diag[44]*x6;
190     yy[7*i+3] = diag[3]*x0 + diag[10]*x1 + diag[17]*x2  + diag[24]*x3 + diag[31]*x4 + diag[38]*x5 + diag[45]*x6;
191     yy[7*i+4] = diag[4]*x0 + diag[11]*x1 + diag[18]*x2  + diag[25]*x3 + diag[32]*x4 + diag[39]*x5 + diag[46]*x6;
192     yy[7*i+5] = diag[5]*x0 + diag[12]*x1 + diag[19]*x2  + diag[26]*x3 + diag[33]*x4 + diag[40]*x5 + diag[47]*x6;
193     yy[7*i+6] = diag[6]*x0 + diag[13]*x1 + diag[20]*x2  + diag[27]*x3 + diag[34]*x4 + diag[41]*x5 + diag[48]*x6;
194     diag     += 49;
195   }
196   ierr = VecRestoreArray(x,&xx);CHKERRQ(ierr);
197   ierr = VecRestoreArray(y,&yy);CHKERRQ(ierr);
198   ierr = PetscLogFlops(80.0*m);CHKERRQ(ierr);
199   PetscFunctionReturn(0);
200 }
201 /* -------------------------------------------------------------------------- */
202 #undef __FUNCT__
203 #define __FUNCT__ "PCSetUp_PBJacobi"
204 static PetscErrorCode PCSetUp_PBJacobi(PC pc)
205 {
206   PC_PBJacobi    *jac = (PC_PBJacobi*)pc->data;
207   PetscErrorCode ierr;
208   Mat            A = pc->pmat;
209 
210   PetscFunctionBegin;
211   if (A->rmap->n != A->cmap->n) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_SUP,"Supported only for square matrices and square storage");
212 
213   ierr        = MatInvertBlockDiagonal(A,&jac->diag);CHKERRQ(ierr);
214   jac->bs     = A->rmap->bs;
215   jac->mbs    = A->rmap->n/A->rmap->bs;
216   switch (jac->bs){
217     case 1:
218       pc->ops->apply = PCApply_PBJacobi_1;
219       break;
220     case 2:
221       pc->ops->apply = PCApply_PBJacobi_2;
222       break;
223     case 3:
224       pc->ops->apply = PCApply_PBJacobi_3;
225       break;
226     case 4:
227       pc->ops->apply = PCApply_PBJacobi_4;
228       break;
229     case 5:
230       pc->ops->apply = PCApply_PBJacobi_5;
231       break;
232     case 6:
233       pc->ops->apply = PCApply_PBJacobi_6;
234       break;
235     case 7:
236       pc->ops->apply = PCApply_PBJacobi_7;
237       break;
238     default:
239       SETERRQ1(((PetscObject)pc)->comm,PETSC_ERR_SUP,"not supported for block size %D",jac->bs);
240   }
241 
242   PetscFunctionReturn(0);
243 }
244 /* -------------------------------------------------------------------------- */
245 #undef __FUNCT__
246 #define __FUNCT__ "PCDestroy_PBJacobi"
247 static PetscErrorCode PCDestroy_PBJacobi(PC pc)
248 {
249   PetscErrorCode ierr;
250 
251   PetscFunctionBegin;
252   /*
253       Free the private data structure that was hanging off the PC
254   */
255   ierr = PetscFree(pc->data);CHKERRQ(ierr);
256   PetscFunctionReturn(0);
257 }
258 
259 #undef __FUNCT__
260 #define __FUNCT__ "PCView_PBJacobi"
261 static PetscErrorCode PCView_PBJacobi(PC pc,PetscViewer viewer)
262 {
263   PetscErrorCode ierr;
264   PC_PBJacobi    *jac = (PC_PBJacobi*)pc->data;
265   PetscBool      iascii;
266 
267   PetscFunctionBegin;
268   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&iascii);CHKERRQ(ierr);
269   if (iascii) {
270     ierr = PetscViewerASCIIPrintf(viewer,"  point-block Jacobi: block size %D\n",jac->bs);CHKERRQ(ierr);
271   } else SETERRQ1(((PetscObject)pc)->comm,PETSC_ERR_SUP,"Viewer type %s not supported for point-block Jacobi",((PetscObject)viewer)->type_name);
272   PetscFunctionReturn(0);
273 }
274 
275 /* -------------------------------------------------------------------------- */
276 /*MC
277      PCPBJACOBI - Point block Jacobi
278 
279    Level: beginner
280 
281   Concepts: point block Jacobi
282 
283 
284 .seealso:  PCCreate(), PCSetType(), PCType (for list of available types), PC
285 
286 M*/
287 
288 EXTERN_C_BEGIN
289 #undef __FUNCT__
290 #define __FUNCT__ "PCCreate_PBJacobi"
291 PetscErrorCode  PCCreate_PBJacobi(PC pc)
292 {
293   PC_PBJacobi    *jac;
294   PetscErrorCode ierr;
295 
296   PetscFunctionBegin;
297 
298   /*
299      Creates the private data structure for this preconditioner and
300      attach it to the PC object.
301   */
302   ierr      = PetscNewLog(pc,PC_PBJacobi,&jac);CHKERRQ(ierr);
303   pc->data  = (void*)jac;
304 
305   /*
306      Initialize the pointers to vectors to ZERO; these will be used to store
307      diagonal entries of the matrix for fast preconditioner application.
308   */
309   jac->diag          = 0;
310 
311   /*
312       Set the pointers for the functions that are provided above.
313       Now when the user-level routines (such as PCApply(), PCDestroy(), etc.)
314       are called, they will automatically call these functions.  Note we
315       choose not to provide a couple of these functions since they are
316       not needed.
317   */
318   pc->ops->apply               = 0; /*set depending on the block size */
319   pc->ops->applytranspose      = 0;
320   pc->ops->setup               = PCSetUp_PBJacobi;
321   pc->ops->destroy             = PCDestroy_PBJacobi;
322   pc->ops->setfromoptions      = 0;
323   pc->ops->view                = PCView_PBJacobi;
324   pc->ops->applyrichardson     = 0;
325   pc->ops->applysymmetricleft  = 0;
326   pc->ops->applysymmetricright = 0;
327   PetscFunctionReturn(0);
328 }
329 EXTERN_C_END
330 
331 
332