int main(int argc, char const *argv[])
{
// int tid; /* thread id */
struct timeval tt;
float e;
long tsec, tusec;
node max_local, sub_local1, sub_local2;
/* initialize global state */
TOTALRESULT = 0.0;
TOTALERROR = 0.0;
int iter = 1;
/* retrieve the start computing time */
gettimeofday(&tt, 0);
tsec = tt.tv_sec;
tusec = tt.tv_usec;
/* create the binary heap */
binary_heap h;
heap_initialize(&h, 2*ITMAX);
/* give the binary heap a root node */
node root = node_create(0, 1);
rule(smooth, &root);
update(root, addition);
heap_insert(&h, root);
// heap_print(h);
#ifdef _OPENMP
/* set the number of threads */
omp_set_num_threads(8);
#pragma omp parallel shared(h, iter, TOTALRESULT, TOTALERROR) private(max_local, sub_local1, sub_local2)
#endif
{
while ((TOTALERROR > ABSREQ) && (iter < ITMAX))
{
#ifdef _OPENMP
#pragma omp critical (retrive_max)
#endif
{
/* this section should be a critical section,
* because each time only one thread can access
* the binary heap */
#ifdef _OPENMP
// printf("Current thread %d is handling the heap, and iteration is %d.\n",
// omp_get_thread_num(), iter);
#endif
max_local = heap_extract_max(&h);
// if (max_local.result == 0.0) continue;
// node_print(max_local);
}
/* divide the max error region into two small regions */
sub_local1 = node_create(max_local.start, (max_local.start
+ max_local.end) / 2.0);
sub_local2 = node_create((max_local.start + max_local.end) / 2.0,
max_local.end);
#ifdef _OPENMP
#pragma omp critical (state_update)
#endif
{
/* critical section, only one thread can access
* the global state each time */
update(max_local, subtraction);
}
/* apply the function, update the result and error */
rule(smooth, &sub_local1);
rule(smooth, &sub_local2);
#ifdef _OPENMP
#pragma omp critical (heap_update)
#endif
{
/* critical section, only one thread can access
* the global state, binary heap
* and variable iter each time */
update(sub_local1, addition);
update(sub_local2, addition);
heap_insert(&h, sub_local1);
heap_insert(&h, sub_local2);
iter++;
}
}
}
// heap_print(h);
/* get the current time, representing the end computing time */
gettimeofday(&tt, 0);
e = (float) (tt.tv_sec - tsec) + (float) (tt.tv_usec - tusec) / 1000000;
printf("It took %g seconds to get the final result %.15f\n", e, TOTALRESULT);
heap_finalize(&h);
printf("total error is: %.40f, and number of iteration is: %d\n", TOTALERROR, iter);
return 0;
}
/* test interface */
void pq_initialize(rtems_task_argument tid, int size ) {
heap_initialize(tid,size);
}
