pcpu_index_alloc_map
int l_bit = find_last_bit(pcpu_index_alloc_map(chunk, s_index),
end = find_next_bit(pcpu_index_alloc_map(chunk, e_index),
l_bit = find_last_bit(pcpu_index_alloc_map(chunk, s_index), s_off);
unsigned long *alloc_map = pcpu_index_alloc_map(chunk, index);
pcpu_index_alloc_map(chunk, s_index),
pcpu_index_alloc_map(chunk, e_index),