magma_int_t
magma_dcg_merge( magma_d_sparse_matrix A, magma_d_vector b, magma_d_vector *x,
magma_d_solver_par *solver_par ){
// prepare solver feedback
solver_par->solver = Magma_CGMERGE;
solver_par->numiter = 0;
solver_par->info = 0;
// some useful variables
double c_zero = MAGMA_D_ZERO, c_one = MAGMA_D_ONE;
magma_int_t dofs = A.num_rows;
// GPU stream
magma_queue_t stream[2];
magma_event_t event[1];
magma_queue_create( &stream[0] );
magma_queue_create( &stream[1] );
magma_event_create( &event[0] );
// GPU workspace
magma_d_vector r, d, z;
magma_d_vinit( &r, Magma_DEV, dofs, c_zero );
magma_d_vinit( &d, Magma_DEV, dofs, c_zero );
magma_d_vinit( &z, Magma_DEV, dofs, c_zero );
double *d1, *d2, *skp;
magma_dmalloc( &d1, dofs*(1) );
magma_dmalloc( &d2, dofs*(1) );
// array for the parameters
magma_dmalloc( &skp, 6 ); // skp = [alpha|beta|gamma|rho|tmp1|tmp2]
// solver variables
double alpha, beta, gamma, rho, tmp1, *skp_h;
double nom, nom0, r0, betanom, den;
// solver setup
magma_dscal( dofs, c_zero, x->val, 1) ; // x = 0
magma_dcopy( dofs, b.val, 1, r.val, 1 ); // r = b
magma_dcopy( dofs, b.val, 1, d.val, 1 ); // d = b
nom0 = betanom = magma_dnrm2( dofs, r.val, 1 );
nom = nom0 * nom0; // nom = r' * r
magma_d_spmv( c_one, A, d, c_zero, z ); // z = A d
den = MAGMA_D_REAL( magma_ddot(dofs, d.val, 1, z.val, 1) ); // den = d'* z
solver_par->init_res = nom0;
// array on host for the parameters
magma_dmalloc_cpu( &skp_h, 6 );
alpha = rho = gamma = tmp1 = c_one;
beta = magma_ddot(dofs, r.val, 1, r.val, 1);
skp_h[0]=alpha;
skp_h[1]=beta;
skp_h[2]=gamma;
skp_h[3]=rho;
skp_h[4]=tmp1;
skp_h[5]=MAGMA_D_MAKE(nom, 0.0);
magma_dsetvector( 6, skp_h, 1, skp, 1 );
if ( (r0 = nom * solver_par->epsilon) < ATOLERANCE )
r0 = ATOLERANCE;
if ( nom < r0 )
return MAGMA_SUCCESS;
// check positive definite
if (den <= 0.0) {
printf("Operator A is not postive definite. (Ar,r) = %f\n", den);
return -100;
}
//Chronometry
real_Double_t tempo1, tempo2;
magma_device_sync(); tempo1=magma_wtime();
if( solver_par->verbose > 0 ){
solver_par->res_vec[0] = (real_Double_t) nom0;
solver_par->timing[0] = 0.0;
}
// start iteration
for( solver_par->numiter= 1; solver_par->numiter<solver_par->maxiter;
solver_par->numiter++ ){
magmablasSetKernelStream(stream[0]);
// computes SpMV and dot product
magma_dcgmerge_spmv1( A, d1, d2, d.val, z.val, skp );
// updates x, r, computes scalars and updates d
magma_dcgmerge_xrbeta( dofs, d1, d2, x->val, r.val, d.val, z.val, skp );
// check stopping criterion (asynchronous copy)
magma_dgetvector_async( 1 , skp+1, 1,
skp_h+1, 1, stream[1] );
betanom = sqrt(MAGMA_D_REAL(skp_h[1]));
if( solver_par->verbose > 0 ){
magma_device_sync(); tempo2=magma_wtime();
if( (solver_par->numiter)%solver_par->verbose==0 ) {
solver_par->res_vec[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) betanom;
solver_par->timing[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) tempo2-tempo1;
}
}
if ( betanom < r0 ) {
break;
}
}
magma_device_sync(); tempo2=magma_wtime();
solver_par->runtime = (real_Double_t) tempo2-tempo1;
double residual;
magma_dresidual( A, b, *x, &residual );
solver_par->iter_res = betanom;
solver_par->final_res = residual;
if( solver_par->numiter < solver_par->maxiter){
solver_par->info = 0;
}else if( solver_par->init_res > solver_par->final_res ){
if( solver_par->verbose > 0 ){
if( (solver_par->numiter)%solver_par->verbose==0 ) {
solver_par->res_vec[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) betanom;
solver_par->timing[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) tempo2-tempo1;
}
}
solver_par->info = -2;
}
else{
if( solver_par->verbose > 0 ){
if( (solver_par->numiter)%solver_par->verbose==0 ) {
solver_par->res_vec[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) betanom;
solver_par->timing[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) tempo2-tempo1;
}
}
solver_par->info = -1;
}
magma_d_vfree(&r);
magma_d_vfree(&z);
magma_d_vfree(&d);
magma_free( d1 );
magma_free( d2 );
magma_free( skp );
magma_free_cpu( skp_h );
return MAGMA_SUCCESS;
} /* magma_dcg_merge */
extern "C" magma_int_t
magma_dcg_merge(
magma_d_matrix A, magma_d_matrix b, magma_d_matrix *x,
magma_d_solver_par *solver_par,
magma_queue_t queue )
{
magma_int_t info = MAGMA_NOTCONVERGED;
// prepare solver feedback
solver_par->solver = Magma_CGMERGE;
solver_par->numiter = 0;
solver_par->spmv_count = 0;
// solver variables
double alpha, beta, gamma, rho, tmp1, *skp_h={0};
double nom, nom0, betanom, den, nomb;
// some useful variables
double c_zero = MAGMA_D_ZERO, c_one = MAGMA_D_ONE;
magma_int_t dofs = A.num_rows*b.num_cols;
magma_d_matrix r={Magma_CSR}, d={Magma_CSR}, z={Magma_CSR}, B={Magma_CSR}, C={Magma_CSR};
double *d1=NULL, *d2=NULL, *skp=NULL;
// GPU workspace
CHECK( magma_dvinit( &r, Magma_DEV, A.num_rows, b.num_cols, c_zero, queue ));
CHECK( magma_dvinit( &d, Magma_DEV, A.num_rows, b.num_cols, c_zero, queue ));
CHECK( magma_dvinit( &z, Magma_DEV, A.num_rows, b.num_cols, c_zero, queue ));
CHECK( magma_dmalloc( &d1, dofs*(1) ));
CHECK( magma_dmalloc( &d2, dofs*(1) ));
// array for the parameters
CHECK( magma_dmalloc( &skp, 6 ));
// skp = [alpha|beta|gamma|rho|tmp1|tmp2]
// solver setup
magma_dscal( dofs, c_zero, x->dval, 1, queue ); // x = 0
//CHECK( magma_dresidualvec( A, b, *x, &r, nom0, queue));
magma_dcopy( dofs, b.dval, 1, r.dval, 1, queue ); // r = b
magma_dcopy( dofs, r.dval, 1, d.dval, 1, queue ); // d = r
nom0 = betanom = magma_dnrm2( dofs, r.dval, 1, queue );
nom = nom0 * nom0; // nom = r' * r
CHECK( magma_d_spmv( c_one, A, d, c_zero, z, queue )); // z = A d
den = MAGMA_D_ABS( magma_ddot( dofs, d.dval, 1, z.dval, 1, queue ) ); // den = d'* z
solver_par->init_res = nom0;
nomb = magma_dnrm2( dofs, b.dval, 1, queue );
if ( nomb == 0.0 ){
nomb=1.0;
}
// array on host for the parameters
CHECK( magma_dmalloc_cpu( &skp_h, 6 ));
alpha = rho = gamma = tmp1 = c_one;
beta = magma_ddot( dofs, r.dval, 1, r.dval, 1, queue );
skp_h[0]=alpha;
skp_h[1]=beta;
skp_h[2]=gamma;
skp_h[3]=rho;
skp_h[4]=tmp1;
skp_h[5]=MAGMA_D_MAKE(nom, 0.0);
magma_dsetvector( 6, skp_h, 1, skp, 1, queue );
if( nom0 < solver_par->atol ||
nom0/nomb < solver_par->rtol ){
info = MAGMA_SUCCESS;
goto cleanup;
}
solver_par->final_res = solver_par->init_res;
solver_par->iter_res = solver_par->init_res;
if ( solver_par->verbose > 0 ) {
solver_par->res_vec[0] = (real_Double_t) nom0;
solver_par->timing[0] = 0.0;
}
// check positive definite
if (den <= 0.0) {
info = MAGMA_NONSPD;
goto cleanup;
}
//Chronometry
real_Double_t tempo1, tempo2;
tempo1 = magma_sync_wtime( queue );
solver_par->numiter = 0;
solver_par->spmv_count = 0;
// start iteration
do
{
solver_par->numiter++;
// computes SpMV and dot product
CHECK( magma_dcgmerge_spmv1( A, d1, d2, d.dval, z.dval, skp, queue ));
solver_par->spmv_count++;
// updates x, r, computes scalars and updates d
CHECK( magma_dcgmerge_xrbeta( dofs, d1, d2, x->dval, r.dval, d.dval, z.dval, skp, queue ));
// check stopping criterion (asynchronous copy)
magma_dgetvector( 1 , skp+1, 1, skp_h+1, 1, queue );
betanom = sqrt(MAGMA_D_ABS(skp_h[1]));
if ( solver_par->verbose > 0 ) {
tempo2 = magma_sync_wtime( queue );
if ( (solver_par->numiter)%solver_par->verbose==0 ) {
solver_par->res_vec[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) betanom;
solver_par->timing[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) tempo2-tempo1;
}
}
if ( betanom < solver_par->atol ||
betanom/nomb < solver_par->rtol ) {
break;
}
}
while ( solver_par->numiter+1 <= solver_par->maxiter );
tempo2 = magma_sync_wtime( queue );
solver_par->runtime = (real_Double_t) tempo2-tempo1;
double residual;
CHECK( magma_dresidualvec( A, b, *x, &r, &residual, queue));
solver_par->iter_res = betanom;
solver_par->final_res = residual;
if ( solver_par->numiter < solver_par->maxiter ) {
info = MAGMA_SUCCESS;
} else if ( solver_par->init_res > solver_par->final_res ) {
if ( solver_par->verbose > 0 ) {
if ( (solver_par->numiter)%solver_par->verbose==0 ) {
solver_par->res_vec[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) betanom;
solver_par->timing[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) tempo2-tempo1;
}
}
info = MAGMA_SLOW_CONVERGENCE;
if( solver_par->iter_res < solver_par->atol ||
solver_par->iter_res/solver_par->init_res < solver_par->rtol ){
info = MAGMA_SUCCESS;
}
}
else {
if ( solver_par->verbose > 0 ) {
if ( (solver_par->numiter)%solver_par->verbose==0 ) {
solver_par->res_vec[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) betanom;
solver_par->timing[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) tempo2-tempo1;
}
}
solver_par->info = MAGMA_DIVERGENCE;
}
cleanup:
magma_dmfree(&r, queue );
magma_dmfree(&z, queue );
magma_dmfree(&d, queue );
magma_dmfree(&B, queue );
magma_dmfree(&C, queue );
magma_free( d1 );
magma_free( d2 );
magma_free( skp );
magma_free_cpu( skp_h );
solver_par->info = info;
return info;
} /* magma_dcg_merge */
