pub fn scheduler_frame_guard_enter(
__arg0: RuntimeScheduleOrigin,
__arg1: RuntimeSchedulerEntry,
) -> RuntimeSchedulerFrameEnterResultExpand description
Enters the current CPU’s exact scheduler switch phase.
The runtime validates entry, disables hardware IRQs, and atomically
creates one CPU-local baton. For RuntimeSchedulerEntry::PreemptExit
and RuntimeSchedulerEntry::IrqReturn, it must transform the exact
final lock-preemption depth into the scheduler depth. For
RuntimeSchedulerEntry::IrqGuardExit, it must instead transform the
final task-context IRQ-publication depth. Neither path may expose a
fully preemptible intermediate state. The runtime must not save this
phase in an execution context or migrate ordinary IRQ tokens with tasks.
RuntimeSchedulerEntry::IrqReturnContinuation must reproduce Linux’s
IRQ-return pass boundary: establish one preemption depth, enable local
IRQs without a live scheduler baton, disable them again, then convert
that exact depth into the next scheduler baton. A successful result
must carry a non-empty task-system capability; a rejected entry returns
the unsafe-context sentinel without live capabilities.