mdb_get_lbolt
extern int64_t mdb_get_lbolt(void);
(clock_t)mdb_get_lbolt() - cpu->cpu_last_swtch);
result = opt_lbolt ? mdb_get_lbolt() : mdb_gethrtime();
if ((args->lbolt = mdb_get_lbolt()) == -1) {
(clock_t)mdb_get_lbolt() - t.t_disp_time);
if ((lbolt = (clock_t)mdb_get_lbolt()) == -1)
if ((thw.thw_lbolt = (clock_t)mdb_get_lbolt()) == -1) {