In my use case, both tasks are in the same thread group, so that works.
I don't see why the requirement is needed though.
Hint is fine, so long as the scheduler seriously considers it.
The cross-cpu limitation is bothersome. Since there are many cpus in
modern machines, particularly ones used for virt, the probability of the
two tasks being on the same cpu is quite low.
error compiling committee.c: too many arguments to function