On 10/09, Peter Zijlstra wrote: > > One thing you might need to consider is the memory ordering, will the > list_empty -- either careful or not -- observe the right list pointer, > or could it -- when racing with wait_event()/prepare_to_wait() -- > observe a stale value. Or.. is that all already covered in on the use > site. I agree. Without spin_lock(q->lock) (or some other barriers) wait_event-like code can miss an event. wait_event: prepare_to_wait(wq) // takes wq->lock if (!CONDITION) schedule(); Now, CONDITION = 1; wake_up(wq); at least need the full mb() before lits_empty(). Oleg. -- To unsubscribe from this list: send the line "unsubscribe linux-serial" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
