Re: [PATCH] [7/9] Add an option to disable direct mapping gbpages and a global variable

[Thomas Gleixner <tglx@linutronix.de>]

On Thu, 31 Jan 2008, Andi Kleen wrote:

> On Thu, Jan 31, 2008 at 05:12:35PM +0100, Thomas Gleixner wrote:
> > On Tue, 29 Jan 2008, Andi Kleen wrote:
> > > +int direct_gbpages;
> > > +
> > > +static int __init parse_direct_gbpages(char *arg)
> > > +{
> > > +	if (!strcmp(arg, "off")) {
> > > +		direct_gbpages = -1;
> > > +		return 0;
> > > +	}
> > > +	return -1;
> > > +}
> > > +early_param("direct_gbpages", parse_direct_gbpages);
> > 
> > Can we please use simple boolean logic ? This 0, -1, 1 magic is more
> > than confusing.
> 
> I did it this way to later allow forcing gbpages. This actually
> makes sense together with debug pagealloc which right now forces
> them to be off.
> 
> The only bit missing for that is a check for direct_gbpages=on

Fair enough. But please use some sensible constants for
that. Otherwise it's just annoying to figure out what 0, -1, 1 and
later on 2 means.

Thanks,
	tglx