thread__comm_list
list_for_each_entry_safe(comm, tmp_comm, thread__comm_list(thread), list) {
if (list_empty(thread__comm_list(thread)))
return list_first_entry(thread__comm_list(thread), struct comm, list);
list_for_each_entry(comm, thread__comm_list(thread), list) {
list_add(&new->list, thread__comm_list(thread));
INIT_LIST_HEAD(thread__comm_list(thread));
list_add(&comm->list, thread__comm_list(thread));