OilfieldToolsNet/LBPM
4
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

add mixed gradient to build on gpu

Browse Source
This commit is contained in:
James McClure
2021-01-22 19:52:18 -05:00
parent 90ba7ed65a
commit 10c5711346
1 changed files with 73 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

73
cuda/MixedGradient.cu Normal file
View File

@@ -0,0 +1,73 @@
/* Implement Mixed Gradient (Lee et al. JCP 2016)*/
#include <cuda.h>
#define NBLOCKS 560
#define NTHREADS 128
__global__ void dvc_ScaLBL_D3Q19_MixedGradient(int *Map, double *Phi, double *Gradient, int start, int finish, int Np, int Nx, int Ny, int Nz)
{
static int D3Q19[18][3]={{1,0,0},{-1,0,0},{0,1,0},{0,-1,0},{0,0,1},{0,0,-1},
{1,1,0},{-1,-1,0},{1,-1,0},{-1,1,0},
{1,0,1},{-1,0,-1},{1,0,-1},{-1,0,1},
{0,1,1},{0,-1,-1},{0,1,-1},{0,-1,1}};
int i,j,k,n,N;
int np,np2,nm; // neighbors
double v,vp,vp2,vm; // values at neighbors
double grad;
int S = N/NBLOCKS/NTHREADS + 1;
for (int s=0; s<S; s++){
//........Get 1-D index for this thread....................
idx = start + S*blockIdx.x*blockDim.x + s*blockDim.x + threadIdx.x;
if (idx<finish){
n = Map[idx]; // layout in regular array
//.......Back out the 3-D indices for node n..............
k = n/(Nx*Ny);
j = (n-Nx*Ny*k)/Nx;
i = n-Nx*Ny*k-Nx*j;
v = Phi[n];
grad = 0.0;
for (int q=0; q<6; q++){
int iqx = D3Q19[q][0];
int iqy = D3Q19[q][1];
int iqz = D3Q19[q][2];
np = (k+iqz)*Nx*Ny + (j+iqy)*Nx + i + iqx;
np2 = (k+2*iqz)*Nx*Ny + (j+2*iqy)*Nx + i + 2*iqx;
nm = (k-iqz)*Nx*Ny + (j-iqy)*Nx + i - iqx;
vp = Phi[np];
vp2 = Phi[np2];
vm = Phi[nm];
grad += 0.25*(5.0*vp-vp2-3.0*v-vm);
}
for (int q=6; q<18; q++){
int iqx = D3Q19[q][0];
int iqy = D3Q19[q][1];
int iqz = D3Q19[q][2];
np = (k+iqz)*Nx*Ny + (j+iqy)*Nx + i + iqx;
np2 = (k+2*iqz)*Nx*Ny + (j+2*iqy)*Nx + i + 2*iqx;
nm = (k-iqz)*Nx*Ny + (j-iqy)*Nx + i - iqx;
vp = Phi[np];
vp2 = Phi[np2];
vm = Phi[nm];
grad += 0.125*(5.0*vp-vp2-3.0*v-vm);
}
Gradient[n] = grad;
}
}
}
extern "C" void ScaLBL_D3Q19_MixedGradient(int *Map, double *Phi, double *Gradient, int start, int finish, int Np, int Nx, int Ny, int Nz)
{
cudaProfilerStart();
dvc_ScaLBL_D3Q19_MixedGradient<<<NBLOCKS,NTHREADS >>>(Map, Phi, Gradient, start, finish, Np, Nx, Ny, Nz);
cudaError_t err = cudaGetLastError();
if (cudaSuccess != err){
printf("CUDA error in ScaLBL_D3Q19_MixedGradient: %s \n",cudaGetErrorString(err));
}
cudaProfilerStop();
}