SW_TYPE_MASK
KASSERT((flags & SW_TYPE_MASK) != 0,
KASSERT((flags & SW_TYPE_MASK) < SWT_COUNT,
("mi_switch: invalid switch reason %d", (flags & SW_TYPE_MASK)));
SCHED_STAT_INC(sched_switch_stats[flags & SW_TYPE_MASK]);
(flags & SW_TYPE_MASK) == SWT_NEEDRESCHED)))