/*
*
* PARALLEL LOOP
*
*/
void loop(int nthreads, int size, int numiter) {
/* VARIABLES */
int i,iter;
/* DECLARE VECTOR AND ANCILLARY DATA STRUCTURES */
double *V=NULL;
double *oldV=NULL;
int totalSize = size*nthreads;
V = (double *)OSCR_calloc(totalSize, sizeof(double));
oldV = (double *)OSCR_calloc(totalSize, sizeof(double));
/* 1. INITIALIZE VECTOR */
for (i=0; i<totalSize; i++) {
V[i]= 0.0 + i;
}
/* 2. START TIMER */
OSCR_timer_start(0);
/* 3. ITERATIONS LOOP */
for(iter=0; iter<numiter; iter++) {
/* 3.1. DUPLICATE THE FULL ARRAY IN PARALLEL */
#pragma omp parallel for default(none) shared(V,oldV,totalSize) private(i) schedule(static)
for (i=0; i<totalSize; i++) {
oldV[i] = V[i];
}
/* 3.2. INNER LOOP: PROCESS ELEMENTS IN PARALLEL */
#pragma omp parallel for default(none) shared(V,oldV,totalSize) private(i) schedule(static)
for (i=0; i<totalSize-1; i++) {
V[i] = f(V[i],oldV[i+1]);
}
/* 3.3. END ITERATIONS LOOP */
}
/* 4. STOP TIMER */
OSCR_timer_stop(0);
/* 5. WRITE VECTOR (DEBUG) */
#ifdef DEBUG
#include "debug_V.c"
#endif
/* 6. END */
}
/* -----------------------------------------------------------------------
IMPLEMENTATION
* ----------------------------------------------------------------------- */
int main(int argc, char **argv) {
int i, j, NUMTHREADS;
long inside, /* no. of points inside the Mandelbrot set */
outside; /* no. of points outside the Mandelbrot set */
double area, error, ztemp, total_time;
complex z;
char *PARAM_NAMES[NUM_ARGS] = {"Number of points"};
char *TIMERS_NAMES[NUM_TIMERS] = {"Total_time"};
char *DEFAULT_VALUES[NUM_ARGS] = {"4092"};
NUMTHREADS = omp_get_max_threads();
OSCR_init (NUMTHREADS, "Mandelbrot set area", "Use 'mandel' <Number of points>", NUM_ARGS,
PARAM_NAMES, DEFAULT_VALUES , NUM_TIMERS, NUM_TIMERS, TIMERS_NAMES,
argc, argv);
NPOINTS = OSCR_getarg_int(1);
/* Default: DEFAULT_NPOINTS */
points = (complex *)OSCR_calloc(NPOINTS, sizeof(complex));
NUMTHREADS = omp_get_max_threads();
/*1. Generate NPOINTS random points in the complex plane */
srandom(31416);
for (i = 0; i < NPOINTS; i++) {
points[i].re = -2.0 + 2.5 * random() / OSCR_RAND_MAX;
points[i].im = 1.125 * random() / OSCR_RAND_MAX;
}
/* * 2. Monte Carlo sampling
* 2a. Outer loop runs over NPOINTS, initialise z=c
* 2b. Inner loop has the iteration z=z*z+c, and threshold test
*/
OSCR_timer_start(0);
outside = 0;
#pragma omp parallel for default(none) reduction(+:outside) \
private(i, j, ztemp, z) shared(NPOINTS, points)
for(i = 0; i < NPOINTS; i++) {
z.re = points[i].re;
z.im = points[i].im;
for (j = 0; j < MAXITER; j++) {
ztemp = (z.re * z.re) - (z.im * z.im) + points[i].re;
z.im = z.re * z.im * 2 + points[i].im;
z.re = ztemp;
if (z.re * z.re + z.im * z.im > THRESOLD) {
outside++;
break;
}
} /* for j */
} /* for i */
inside = (long)NPOINTS - outside;
/*3. Calculate area and error */
/* The area is proportional to 2 * the area of the rectangle * no. of points inside it */
/* The error is inversely proportional to the square root of the number of test cases */
area = 2.0 * (2.5 * 1.125) * inside / NPOINTS;
error = area / sqrt(NPOINTS);
OSCR_timer_stop(0);
total_time = OSCR_timer_read(0);
/* 4. Output the Results */
OSCR_report(1, TIMERS_NAMES);
printf("\n \t# THREADS NPOINTS AREA \t\t\tERROR \t\tTIME (secs.)\n");
// printf("\t%d \t%d \t%16.12f %16.12f \t%lf\n", NUMTHREADS, NPOINTS, area, error, total_time);
printf("\t%d \t%d \t%16.12f %16.12f \t\n", NUMTHREADS, NPOINTS, area, error);
return 0;
}
/*
*
* Graph search. Test if exists a path from a source node to a target node
*
* Parallelization method: Shared-Memory workers-farm
*
*/
void testPath(int nthreads, int source, int target, tg graph) {
/* SHARED STRUCTURES */
Bool *searched=NULL;
Astack pool;
Bool found = FALSE;
int ind;
/* ENDING CONTROL */
int num_waiting=0;
/* 1. ALLOCATE MEMORY FOR ANCILLARY STRUCTURES */
pool = Ast_init();
searched = OSCR_calloc(tg_nodes(graph), sizeof(Bool));
for (ind=0; ind<tg_nodes(graph); ind++) { searched[ind]=FALSE; }
/* 2. INIT "nodes to explore" POOL WITH THE source ID */
Ast_push(pool, source);
/* 3. START TIMER */
OSCR_timer_start(0);
/* 4. SPAWN WORKERS */
#pragma omp parallel default(none) \
shared(nthreads,num_waiting,graph,searched,pool,target,found)
{
Bool waiting = FALSE;
tg_task next=TG_NULLID;
task_list succs;
int num_succs;
int ind;
#ifdef DEBUG
int numPops=0;
int numNoPops=0;
int thread = omp_get_thread_num();
#endif
/* WORKER WORKS UNTIL:
* ALL WORKERS ARE WAITING (TARGET NOT FOUND)
* OR SOMEONE FINDS THE TARGET
*/
while ( num_waiting != nthreads && !found ) {
/* 1. GET NEXT ELEMENT TO PROCESS (OR WAIT UNTIL MORE ELEMENTS) */
while( next == TG_NULLID && num_waiting != nthreads && !found) {
/* ALL POOL OPERATIONS ARE MONITORIZED */
#pragma omp critical
{
/* 1.1. CHECK THE POOL */
if ( Ast_more(pool) ) {
/* 1.1.1. ELEMENTS IN THE POOL: GET NEXT */
next = Ast_pop(pool);
#ifdef DEBUG
numPops++;
#endif
/* 1.1.2. IF WAITING, CHANGE STATE */
if ( waiting ) {
waiting = FALSE;
num_waiting--;
}
}
else {
/* 1.1.3. EMPTY POOL: IF NOT WAITING, CHANGE STATE */
#ifdef DEBUG
numNoPops++;
#endif
if ( !waiting ) {
waiting = TRUE;
num_waiting++;
}
}
/* OMP END CRITICAL: MONITORIZED OPERATION */
}
} /* END GET next ELEMENT FROM THE POOL */
/* 2. PROCESS next ELEMENT */
if ( next != TG_NULLID ) {
/* 2.1. TARGET FOUND: END ALL */
if (next == target) { found = TRUE; }
/* 2.2. NO SUCCESORS: END */
else if ( tg_succ_num(graph, next) == 0 ) { next = TG_NULLID; }
/* 2.3. GET SUCCESORS LIST AND PUSH IT TO THE POOL */
else {
/* 2.3.1. GET SUCCS LIST */
num_succs = tg_succ_num(graph, next);
succs = tg_succ(graph, next);
/* 2.3.2. PUSH SUCCS TO POOL: MONITORIZED OPERATION */
#pragma omp critical
if ( num_succs > 0 ) {
for(ind=0; ind<num_succs; ind++) {
tg_task vp = succs[ind];
/* PUSH ONLY NON-EXPLORED NODES */
if ( ! searched[ vp ] ) {
searched[ vp ] = TRUE;
Ast_push(pool, vp);
}
}
/* END OMP CRITICAL: MONITORIZED OPERATION */
}
}
/* 2.4. END PROCESSING ELEMENT */
next = TG_NULLID;
}
} /* END PROCESSING */
#ifdef DEBUG
printf("#DEBUG Thread %d ENDING ----> Pops: %d, NoPops: %d\n",thread,numPops,numNoPops);
#endif
/* WORKERS END: PARALLEL REGION */
}
/* 5. STOP TIMER */
OSCR_timer_stop(0);
/* 6. WRITE RESULT */
printf("\nPath(%d,%d) = %d\n\n", source, target, found);
/* 7. END */
}
/*
*
* PARALLEL LOOP
*
*/
void loop(int nthreads, int size, int numiter) {
/* VARIABLES */
int i,iter;
int thread;
int limitL, limitR;
/* DECLARE VECTOR AND ANCILLARY DATA STRUCTURES */
double *V=NULL;
double border;
int totalSize = size*nthreads;
V = (double *)OSCR_calloc(totalSize, sizeof(double));
/* 1. INITIALIZE VECTOR */
for (i=0; i<totalSize; i++) {
V[i]= 0.0 + i;
}
/* 2. GET TIMER */
OSCR_timer_start(0);
/* 3. ITERATIONS LOOP */
for(iter=0; iter<numiter; iter++) {
/* 3.1. PROCESS IN PARALLEL */
#pragma omp parallel default(none) shared(V,size,nthreads,numiter) private(iter,thread,limitL,limitR,border,i)
{
/* 3.1.1. GET NUMBER OF THREAD */
thread = omp_get_thread_num();
/* 3.1.2. COMPUTE LIMIT INDEX */
limitL = thread*size;
limitR = (thread+1)*size-1;
/* 3.1.3. COPY OTHER THREADS's NEIGHBOR ELEMENT */
if (thread != nthreads) border = V[limitR+1];
/* 3.1.4. SYNCHRONIZE BEFORE UPDATING LOCAL PART */
#pragma omp barrier
/* 3.1.5. COMPUTE LOCAL UPDATES */
for (i=limitL; i<limitR; i++) {
V[i] = f( V[i], V[i+1] );
}
/* 3.1.6. COMPUTE LAST ELEMENT (EXCEPT LAST THREAD) */
if (thread != nthreads-1)
V[limitR] = f( V[limitR], border );
/* 3.1.7. END PARALLEL REGION */
}
/* 3.2. END ITERATIONS LOOP */
}
/* 4. STOP TIMER */
OSCR_timer_stop(0);
/* 5. WRITE VECTOR (DEBUG) */
#ifdef DEBUG
#include "debug_V.c"
#endif
/* 6. END */
}
/*
*
* PARALLEL LOOP
*
*/
void loop(int nthreads, int size, int numiter) {
/* VARIABLES */
int i,iter;
int thread;
int limitL, limitR;
/* DECLARE VECTOR AND ANCILLARY DATA STRUCTURES */
double *V=NULL;
double border;
int totalSize = size*nthreads;
V = (double *)OSCR_calloc(totalSize, sizeof(double));
/* 1. INITIALIZE VECTOR */
for (i=0; i<totalSize; i++) {
V[i]= 0.0 + i;
}
/* 2. START TIMER */
OSCR_timer_start(0);
/* 3. PROCESS IN PARALLEL */
#pragma omp parallel default(none) shared(V,size,nthreads,numiter) private(iter,thread,limitL,limitR,border,i)
{
/* 3.1. GET MY NUMBER OF THREAD IN THE GROUP */
thread = omp_get_thread_num();
/* 3.2. COMPUTE MY LIMIT INDEX */
limitL = thread*size;
limitR = (thread+1)*size-1;
/* 3.3. ITERATIONS LOOP (+nthreads EXTRA ITER. TO EMPTY THE PIPELINE) */
for(iter=0; iter<(numiter+nthreads-1); iter++) {
/* 3.3.1. COPY OTHER THREADS's NEIGHBOR ELEMENT */
if (thread != 0) border = V[limitL-1];
/* 3.3.2. SYNCHRONIZE BEFORE UPDATING LOCAL PART */
#pragma omp barrier
/* 3.3.3. COMPUTE LOCAL UPDATES */
/* (ONLY ACTIVE THREADS - CHECK PIPELINE STAGE) */
if ( thread<=iter && thread>(iter-numiter) ) {
/* 3.3.3.1. COMPUTE FIRST ELEMENT (EXCEPT THREAD 0) */
if (thread != 0)
V[limitL] = f( V[limitL], border );
/* 3.3.3.2. COMPUTE THE REST OF ELEMENTS */
for (i=limitL+1; i<=limitR; i++) {
V[i] = f( V[i], V[i-1] );
}
}
/* 3.3.4. SYNCHRONIZE BEFORE COPYING UPDATED BORDER ELEMENT */
#pragma omp barrier
/* 3.3.5. END ITERATIONS LOOP */
}
/* 3.4. END PARALLEL REGION */
}
/* 4. STOP TIMER */
OSCR_timer_stop(0);
/* 5. WRITE VECTOR (DEBUG) */
#ifdef DEBUG
#include "debug_V.c"
#endif
/* 6. END */
}
