exec_entry
struct exec_entry *it;
static LIST_HEAD(execlist_head, exec_entry) ex_head =
LIST_ENTRY(exec_entry) ex_list;
SLIST_ENTRY(exec_entry) ex_slist;
struct exec_entry *it, *next;
struct exec_entry *ex;
SLIST_HEAD(,exec_entry) first;
SLIST_HEAD(,exec_entry) any;
SLIST_HEAD(,exec_entry) last;