On Sat, Jun 25, 2016 at 06:09:22PM +0200, Peter Zijlstra wrote: > That works here, but it would not work for the need_resched() in > mutex_spin_on_owner() and mutex_optimistic_spin() which need equal > treatment. > > Because those too we want to limit. > > The count thing, while a little more cumbersome, is more widely > applicable than just the one OSQ case where we happen to have a cpu > number.
Although I suppose that mutex_spin_on_owner() (and with that the rsem variant) could use task_cpu(lock->owner) once we've established that the owner pointer is still valid.
