void pbksb(void) {
register int i,j;
register double sum;
int pid;
double *b;
int n,p;
GET_PID(pid);
b = gm->b;
n = gm->n;
p = gm->p;
double *a_prime;
a_prime = gm->a_prime;
//--------------------------------------------------
// Parallelize the consecutive substract operations
//--------------------------------------------------
for (i = n-p+pid; i >= pid; i -= p)
{
sum = b[i];
for (j = n-1; j > i; j--)
{
WAITPAUSE(gm->pse[j])
sum -= a_prime[(n-i) * (n-1-i)/2 + (n-1-j)] * b[j];
}
b[i] = sum / a_prime[(n-i) * (n-1-i)/2 + (n-1-i)];
SETPAUSE(gm->pse[i])
}
}
//
//
// Return the array indices of a sub-array that needs sorting.
// int PopWork(TaskElement *);
//
//
int PopWork(TaskElement * task){
int i;
if (!Sequential) {
//Tmk_lock_acquire(gMem->TaskStackLock);
pthread_taskstack_lock(gMem->TaskStackLock);
while (gMem->TaskStackTop == 0) { // Check for empty stack!
if (++gMem->NumWaiting == Tmk_nprocs) {
// DONE
SETPAUSE(pauseFlag);
//Tmk_lock_release(gMem->TaskStackLock);
pthread_taskstack_unlock(gMem->TaskStackLock);
return(DONE);
}
else {
// Wait for some work to get pushed on...
if (gMem->NumWaiting == 1){
CLEARPAUSE(pauseFlag);
}
//Tmk_lock_release(gMem->TaskStackLock);
pthread_taskstack_unlock(gMem->TaskStackLock);
if (debug){
fprintf(stderr,"\t%d: PopWork waiting for work.\n",Tmk_proc_id);
}
WAITPAUSE(pauseFlag);
//Tmk_lock_acquire(gMem->TaskStackLock);
pthread_taskstack_lock(gMem->TaskStackLock);
if (gMem->NumWaiting == Tmk_nprocs) {
//Tmk_lock_release(gMem->TaskStackLock);
pthread_taskstack_unlock(gMem->TaskStackLock);
return(DONE);
}
--gMem->NumWaiting;
}// end of else
} // while task-stack empty
}
else // non-sequential
if (gMem->TaskStackTop == 0) {
return(DONE);
}
gMem->TaskStackTop--;
task->left = gMem->TaskStack[gMem->TaskStackTop].left;
task->right = gMem->TaskStack[gMem->TaskStackTop].right;
if (debug) {
fprintf(stderr,"\t%d: PopWork - returning <%d,%d>. Top now %d.\n",
Tmk_proc_id, task->left, task->right,
gMem->TaskStackTop);
}
if (!Sequential) {
//Tmk_lock_release(gMem->TaskStackLock);
pthread_taskstack_unlock(gMem->TaskStackLock);
}
return(0);
}
