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#include <stdio.h>
#include <stdlib.h>
#include <complex.h>
#include <math.h>
#include <unistd.h>
#include <pthread.h>
typedef struct
{
int core;
int cores;
int size;
double power;
unsigned int iterat;
char* data;
pthread_t thread;
} data_section;
void *generate_section(void *d);
int main(int argc, char **argv)
{
int size, iterat, cores,i;
double power;
if (argc != 4)
{
fprintf(stderr, "%s size iterat power", argv[0]);
return EXIT_FAILURE;
}
size = atoi(argv[1]);
iterat = atoi(argv[2]);
power = atof(argv[3]);
// Fetch number of cores available on machine, so we can use lots of them to speed things up
cores = sysconf (_SC_NPROCESSORS_ONLN);
// cores = 8;
// TO DO: assertions for size, iterat, power and cores
fprintf(stderr, "Found %d cores. I'll spawn as many threads and let the scheduler sort it out.\n", cores);
// TO DO: move to top of function
int x,y,s;
data_section* sections = malloc(sizeof(data_section)*cores);
fprintf(stderr, "Spawning threads:\n");
// Spawn all the threads! Something something interlacing
for (i = 0; i < cores; i++)
{
// Has to be a better way
sections[i].core = i;
sections[i].cores = cores;
sections[i].size = size;
sections[i].power = power;
sections[i].iterat = iterat;
fprintf(stderr, " -> Thread #%d\n", i);
pthread_create(§ions[i].thread, NULL, &generate_section, &(sections[i]));
}
// Wait for each thread to complete
for (i = 0; i < cores; i++)
pthread_join(sections[i].thread, NULL);
// Vomit the data segments back onto the screen, deinterlacing
// TO DO: look at fwrite performance benefits over putchar
for (y = 0; y < size; y++)
for (x = 0; x < size; x++)
putchar(sections[y%cores].data[(y/cores)*size + x]);
// Free the memory we allocated for point data
for (s = 0; s < cores; s++)
free(sections[s].data);
fprintf(stderr,"\n");
return 0;
}
void *generate_section(void *section)
{
data_section *d = (data_section*)section;
d->data = malloc((d->size*d->size)/d->cores);
unsigned int x,y,i;
double a,b;
double complex z,c;
int idx = 0;
// TO DO: assert malloc succeeded
for (y = d->core, b = (d->core*(3.5f/d->size)-1.75f); y < d->size; b+=((d->cores*3.5f)/d->size), y+=d->cores)
{
for (x = 0, a = -2.5f; x < d->size; a+=(3.5f/d->size), x++)
{
z = 0;
c = a+I*b;
for (i = 0; i < d->iterat; i++)
{
if (cabsf(z) >= 2)
break;
z = cpow(z, d->power)+c;
}
d->data[idx++] = (255*i)/d->iterat;
}
}
return NULL;
}
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