Requeueing of tasks from a non-PI futex to a PI futex requires
special handling in order to ensure the underlying rt_mutex is never
left without an owner if it has waiters; doing so would break the PI
Requeueing of tasks from a non-PI futex to a PI futex requires
special handling in order to ensure the underlying rt_mutex is never
left without an owner if it has waiters; doing so would break the PI