Re: [RFC 06/15] PM / Hibernate: swap, remove swap_map_handle usages

Rafael J. Wysocki
2010-03-25T21:35:35Z

On Wednesday 24 March 2010, Jiri Slaby wrote:
> On 03/24/2010 09:33 PM, Pavel Machek wrote:
> > On Tue 2010-03-23 17:17:34, Jiri Slaby wrote:
> >> Some code, which will be moved out of swap.c, needs know nothing about
> >> swap. There will be also other than swap writers later, so that it
> >> won't make sense at all.
> >>
> >> Make it a global static in swap.c as a singleton.
> >
> > I guess I just dislike global static. Logically, methods do operate on
> > handles, so...
>
> Ok, "upper layers" may get a handle via .get_reader/writer. The downside
> is that they would have to get (void *) and pass (void *) down again. I
> wanted to avoid that (taking into account that it's a singleton).
>
> > I don't see a point and I do not think the change is an improvement.
>
> The point was to avoid (void *)'s and save users from transferring
> pointer as a handle. No matter what, the decision is not up to me,
> discussion indeed welcome.

The whole thing boils down to whether or not there may be more than one
swap map in use at a time.

Perhaps it's better to use a static pointer, though?

And I don't really know at this point how exactly this change is going to make
your life easier down the road. Care to elaborate?

Rafael