Re: wake_up_process implied memory barrier clarification

Oleg Nesterov
2015-08-31T18:36:14Z

On 08/31, Boqun Feng wrote:
>
> Fair enough, I went too far. How about just a single paragraph saying
> that:
>
> The wake_up(), wait_event() and their friends have proper barriers in
> them, but these implicity barriers are only for the correctness for
> sleep and wakeup. So don't rely on these barriers for things that are
> neither wait-conditons nor task states.
>
> Is that OK to you?

Ask Paul ;) but personally I agree.

To me, the only thing a user should know about wake_up/try_to_wake_up
and barriers is that you do not need another barrier between setting
condition and waking up.

Oleg.