Re: [PATCH 2/4] swait: add the missing killable swaits

[Davidlohr Bueso]

On Thu, 29 Jun 2017, Linus Torvalds wrote:

> Well, I'd actually say it the other way around: swait should not be
> used in general, only in _very_ particular pieces of code that
> actually explicitly need the odd swait semantics.
>
> swait uses special locking and has odd semantics that are not at all
> the same as the default wait queue ones. It should not be used without
> very strong reasons (and honestly, the only strong enough reason seems
> to be "RT").
>
> The special locking means that swait doesn't do DEBUG_LOCK_ALLOC, but
> it also means that it doesn't even work in all contexts.
>
> So "swake_up()" does surprising things (only wake up one - that's what
> caused a firmware loading bug), and "swake_up_all()" has magic rules
> about interrupt disabling.
>
> The thing is simply a collection of small hacks and should NOT be used
> in general.

For all the above, what do you think of my 'sswait' proposal?

Thanks,
Davidlohr