1 2 /* 3 Additive Multigrid V Cycle routine 4 */ 5 #include <petsc/private/pcmgimpl.h> 6 7 PetscErrorCode PCMGACycle_Private(PC pc,PC_MG_Levels **mglevels) 8 { 9 PetscErrorCode ierr; 10 PetscInt i,l = mglevels[0]->levels; 11 12 PetscFunctionBegin; 13 /* compute RHS on each level */ 14 for (i=l-1; i>0; i--) { 15 if (mglevels[i]->eventinterprestrict) {ierr = PetscLogEventBegin(mglevels[i]->eventinterprestrict,0,0,0,0);CHKERRQ(ierr);} 16 ierr = MatRestrict(mglevels[i]->restrct,mglevels[i]->b,mglevels[i-1]->b);CHKERRQ(ierr); 17 if (mglevels[i]->eventinterprestrict) {ierr = PetscLogEventEnd(mglevels[i]->eventinterprestrict,0,0,0,0);CHKERRQ(ierr);} 18 } 19 /* solve separately on each level */ 20 for (i=0; i<l; i++) { 21 ierr = VecSet(mglevels[i]->x,0.0);CHKERRQ(ierr); 22 if (mglevels[i]->eventsmoothsolve) {ierr = PetscLogEventBegin(mglevels[i]->eventsmoothsolve,0,0,0,0);CHKERRQ(ierr);} 23 ierr = KSPSolve(mglevels[i]->smoothd,mglevels[i]->b,mglevels[i]->x);CHKERRQ(ierr); 24 if (mglevels[i]->eventsmoothsolve) {ierr = PetscLogEventEnd(mglevels[i]->eventsmoothsolve,0,0,0,0);CHKERRQ(ierr);} 25 } 26 for (i=1; i<l; i++) { 27 if (mglevels[i]->eventinterprestrict) {ierr = PetscLogEventBegin(mglevels[i]->eventinterprestrict,0,0,0,0);CHKERRQ(ierr);} 28 ierr = MatInterpolateAdd(mglevels[i]->interpolate,mglevels[i-1]->x,mglevels[i]->x,mglevels[i]->x);CHKERRQ(ierr); 29 if (mglevels[i]->eventinterprestrict) {ierr = PetscLogEventEnd(mglevels[i]->eventinterprestrict,0,0,0,0);CHKERRQ(ierr);} 30 } 31 PetscFunctionReturn(0); 32 } 33