On Fri, Feb 28, 2025 at 07:29:45AM -0800, Sean Christopherson wrote: > On Fri, Feb 28, 2025, Keith Busch wrote: > > On Fri, Feb 28, 2025 at 06:32:47AM -0800, Sean Christopherson wrote: > > > > @@ -35,10 +35,12 @@ static inline int call_once(struct once *once, int (*cb)(struct once *)) > > > > return 0; > > > > > > > > guard(mutex)(&once->lock); > > > > - WARN_ON(atomic_read(&once->state) == ONCE_RUNNING); > > > > - if (atomic_read(&once->state) != ONCE_NOT_STARTED) > > > > + if (WARN_ON(atomic_read(&once->state) == ONCE_RUNNING)) > > > > return -EINVAL; > > > > > > > > + if (atomic_read(&once->state) == ONCE_COMPLETED) > > > > + return 0; > > > > + > > > > atomic_set(&once->state, ONCE_RUNNING); > > > > r = cb(once); > > > > if (r) > > > > Possible suggestion since it seems odd to do an atomic_read twice on the > > same value. > > Yeah, good call. At the risk of getting too cute, how about this? Sure, that also looks good to me.