/* ============================================================================
Function: = Mpi_Bitonic_sort
Purpose: = The root itteration logic for the bitonic sequence sort.
==============================================================================
Input arg: = 1. my_rank: The size of the processors array.
= 2. p: The size of the input array.
= 3. my_list[]: A pointer to an array.
= 4. neighbors_list[]: A pointer to an array.
= 5. list_size: The size of the processors array.
= 6. comm: The mpi communicator channel.
=========================================================================== */
void Mpi_Bitonic_sort(int my_rank, int p, int my_list[], int neighbors_list[],
int list_size, MPI_Comm comm)
{
int partner_size, phase = 1;
unsigned and_bit;
for(partner_size = 2, and_bit = 2; partner_size <= p;
partner_size = partner_size * 2, and_bit = and_bit << 1)
{
if((my_rank & and_bit) == 0)
{
#ifdef DEBUG
Debugger(1, my_rank, phase, partner_size, my_list, p*list_size,
list_size);
#endif
Bitonic_sort_incr(my_rank, my_list, neighbors_list, list_size,
partner_size, comm);
}
else
{
#ifdef DEBUG
Debugger(2, my_rank, phase, partner_size, my_list, p*list_size,
list_size);
#endif
Bitonic_sort_decr(my_rank, my_list, neighbors_list, list_size,
partner_size, comm);
}
#ifdef DEBUG
Debugger(3, my_rank, phase, partner_size, my_list, p*list_size,
list_size);
#endif
phase++;
}
if(my_rank == 0) printf("The list is now sorted. \n");
Gather(my_list, p*list_size, my_rank, list_size);
}
/*-------------------------------------------------------------------
* Function: Bitonic_sort
* Purpose: Implement bitonic sort of a list of ints
* In arg: rank
* In globals: barrier, thread_count, n (list size), list1
* Out global: l_a
* Scratch globals: list2, l_b
* Return val: Ignored
*/
void *Bitonic_sort(void* rank) {
long tmp = (long) rank;
int my_rank = (int) tmp;
int local_n = n/thread_count;
int my_first = my_rank*local_n;
// int my_last = my_first + local_n - 1;
unsigned th_count, and_bit, dim;
/* Sort my sublist */
qsort(list1 + my_first, local_n, sizeof(int), Compare);
Barrier();
# ifdef DEBUG
if (my_rank == 0) Print_list("List after qsort", list1, n);
# endif
for (th_count = 2, and_bit = 2, dim = 1; th_count <= thread_count;
th_count <<= 1, and_bit <<= 1, dim++) {
if ((my_rank & and_bit) == 0)
Bitonic_sort_incr(th_count, dim, my_first, local_n, my_rank);
else
Bitonic_sort_decr(th_count, dim, my_first, local_n, my_rank);
}
return NULL;
} /* Bitonic_sort */
