intel多核大学————多核程序设计源码

/* compute the potential energy of a collection of */ /* particles interacting via pairwise potential */ #include <stdio.h> #include <stdlib.h> #include <math.h> #include <windows.h> #define NPARTS 1000 #define NITER 301 #define DIMS 3 #define NUM_THREADS 2 //int rand( void ); DWORD WINAPI tPoolComputePot(LPVOID); void computePot(int); void initPositions(void); void updatePositions(void); double r[DIMS][NPARTS]; int bounds[2][NUM_THREADS]; double pot; double gPot[NUM_THREADS]; int done = 0; HANDLE bSignal[NUM_THREADS]; // signal to begin computation HANDLE eSignal[NUM_THREADS]; // signal that computation is ended int main() { int i, j; HANDLE tHandle[NUM_THREADS]; int tNum[NUM_THREADS]; for (i=0; i<NUM_THREADS; i++) { bounds[0][i] = i * (NPARTS/NUM_THREADS); bounds[1][i] = (i+1) * (NPARTS/NUM_THREADS); bSignal[i] = CreateEvent(NULL, FALSE, FALSE, NULL); // auto-reset eSignal[i] = CreateEvent(NULL, FALSE, FALSE, NULL); // auto-reset } bounds[1][NUM_THREADS-1] = NPARTS; for (j=0; j<NUM_THREADS; j++) { tNum[j] = j; tHandle[j] = CreateThread(NULL, 0, tPoolComputePot, &tNum[j], 0, NULL); } initPositions(); updatePositions(); for( i=0; i<NITER; i++ ) { WaitForMultipleObjects(NUM_THREADS, eSignal, TRUE, INFINITE); pot = 0.0; for (j=0; j<NUM_THREADS; j++) { pot += gPot[j]; } if (i%10 == 0) printf("%5d: Potential: %10.3f\n", i, pot); updatePositions(); } done = 1; for (j=0; j<NUM_THREADS; j++) SetEvent(bSignal[i]); WaitForMultipleObjects(NUM_THREADS, tHandle, TRUE, INFINITE); } void initPositions() { int i, j; for( i=0; i<DIMS; i++ ) for( j=0; j<NPARTS; j++ ) r[i][j] = 0.5 + ( (double) rand() / (double) RAND_MAX ); } void updatePositions() { int i, j; for( i=0; i<DIMS; i++ ) for( j=0; j<NPARTS; j++ ) r[i][j] -= 0.5 + ( (double) rand() / (double) RAND_MAX ); for (j=0; j<NUM_THREADS; j++) SetEvent(bSignal[j]); } DWORD WINAPI tPoolComputePot(LPVOID pArg) { int tid = *(int *)pArg; while (!done) { WaitForSingleObject(bSignal[tid], INFINITE); computePot(tid); SetEvent(eSignal[tid]); } return 0; } void computePot(int tid) { int i, j, start, end; double lPot = 0.0; double distx, disty, distz, dist; start = bounds[0][tid]; end = bounds[1][tid]; for( i=start; i<end; i++ ) { for( j=0; j<i-1; j++ ) { distx = pow( (r[0][j] - r[0][i]), 2 ); disty = pow( (r[1][j] - r[1][i]), 2 ); distz = pow( (r[2][j] - r[2][i]), 2 ); dist = sqrt( distx + disty + distz ); lPot += 1.0 / dist; } } gPot[tid] = lPot; }