Re: [PATCH 06/13] cpuset: cleanup cpuset[_can]_attach()

From: Tejun Heo
Date: Wed Jan 02 2013 - 10:34:29 EST


Hello, Rusty.

On Wed, Jan 02, 2013 at 03:12:15PM +1030, Rusty Russell wrote:
> > Hmmm? cpumask_t can't be used for stack but other than that I don't
> > see how it would be deprecated completely. Rusty, can you please
> > chime in?
>
> The long-never-quite-complete-plan was for struct cpumask to be
> undefined when CONFIG_CPUMASK_OFFSTACK=y. That means noone can declare
> them, or pass them on the stack, since they'll get a compiler error.
>
> Now, there are some cases where it really is a reason to use a static
> bitmap, and 1/2 a K of wasted space be damned. There's a
> deliberately-ugly way of doing that: declare a bitmap and use
> to_cpumask(). Of course, if we ever really want to remove NR_CPUS and
> make it completely generic, we have to kill all these too, but noone is
> serious about that.

So, I guess this currently is caught in a place which isn't here or
there. I'm pretty skeptical whether it makes sense to bother about
static usages tho. Can I keep them for static ones?

Thanks.

--
tejun
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/