`_current` is now functionally equals to `arch_curr_thread()`, remove
its usage in-tree and deprecate it instead of removing it outright,
as it has been with us since forever.
Signed-off-by: Yong Cong Sin <ycsin@meta.com>
Signed-off-by: Yong Cong Sin <yongcong.sin@gmail.com>
Adds a test to show that enabling IPI cascades
(CONFIG_SCHED_IPI_CASCADE=y) can correct an invalid set
of high priority threads on an N CPU system.
Signed-off-by: Peter Mitsis <peter.mitsis@intel.com>