Re: Singlethread vs. freezable workqueues

Alan Stern
2007-05-21T20:23:33Z

On Mon, 21 May 2007, Rafael J. Wysocki wrote:

> Hi,
>
> On Monday, 21 May 2007 21:33, Alan Stern wrote:
> > Raphael:
> >
> > Are we now committed to making freezable workqueues always
> > singlethreaded? Is it at all likely to change back? Or should I
> > introduce a "create_singlethread_freezeable_workqueue" macro?
>
> This was done as a quick fix of an issue with one driver that started to use
> (broken) freezable workqueues when we were not watching. ;-)
>
> We are going to have multithread freezable workqueues as well, but that'll
> take some time. We've discussed this a bit with Oleg and I believe he has an
> idea of how it can be done cleanly.

The reason I asked is because, prior to the release of 2.6.22, I sent
in a patch which added a create_singlethread_freezeable_workqueue()
macro. Now it isn't needed, since create_freezeable_workqueue() does
the same thing. Is there any reason to keep the macro?

I'm worried that if I get rid of it and simply define the workqueue as
freezable, then at some time in the future it might turn into a
multithread workqueue without my knowledge.

Alan Stern