On 01/15, Davidlohr Bueso wrote: > > On Thu, 22 Dec 2016, Bueso wrote: > >> + WARN_ON(current->exit_state); \ > > While not related to this patch, but per 3245d6acab9 (exit: fix race > between wait_consider_task() and wait_task_zombie()), should we not > *_ONCE() all things ->exit_state?
current->exit_state != 0 is stable. I mean, only current can change it from zero to non-zero, and once it is non-zero it can't be zero again. > I'm not really refering to a specific > bug (much less here, where that race would not matter obviously), but > if nothing else, for documentation Oh, I won't argue but I do not agree. To me, READ_ONCE() often adds some confusion because I can almost never understand if it is actually needed for correctness or it was added "just in case". Oleg.
