On Fri, May 20, 2016 at 08:00:49AM -0700, Davidlohr Bueso wrote: > On Fri, 20 May 2016, Peter Zijlstra wrote: > > >On Thu, May 19, 2016 at 10:39:26PM -0700, Davidlohr Bueso wrote: > >> In addition, this makes me wonder if queued_spin_is_locked() should then > >> be: > >> > >>- return atomic_read(&lock->val); > >>+ return atomic_read(&lock->val) & _Q_LOCKED_MASK; > >> > >>And avoid considering pending waiters as locked. > > > >Probably > > Similarly, and I know you hate it, but afaict, then semantically > queued_spin_is_contended() ought to be: > > - return atomic_read(&lock->val) & ~_Q_LOCKED_MASK; > + return atomic_read(&lock->val);
Nah, that would make it return true for (0,0,1), ie. uncontended locked.
