Re: [2.6 patch] let SUSPEND select HOTPLUG_CPU

[Adrian Bunk <bunk@stusta.de>]

On Sat, Jul 28, 2007 at 12:47:37AM +0200, Stefan Richter wrote:
> Adrian Bunk wrote:
> > The dependency of SUSPEND_SMP on HOTPLUG_CPU is quite unintuitive,
> 
> It's not entirely unintuitive.  That option's full name is "Support for
> suspend on SMP and hot-pluggable CPUs".
> 
> Only the place where you find the option is unintuitive, as far as its
> first application is concerned.  (It lives in the "Processor type and
> features" menu which is OK for the 2nd application of this option.)  And
> the variable name of that option is unintuitive because it covers only
> the 2nd application of the option, I suppose for historical reasons.

We can figure out ourselves when HOTPLUG_CPU is required, so there's no 
reason to bother the user with it.

> > +config SUSPEND_SMP_POSSIBLE
> > +	bool
> > +	depends on (X86 && !X86_VOYAGER) || (PPC64 && (PPC_PSERIES || PPC_PMAC))
> > +	depends on SMP
> > +	default y
> > +
> > +config SUSPEND_SMP
> > +	bool
> > +	depends on SUSPEND_SMP_POSSIBLE && SOFTWARE_SUSPEND
> > +	select HOTPLUG_CPU
> > +	default y
> 
> Yes, that's the price to pay if you want to select something that in
> turn depends on a number of other things.

Yes, but a good user interface is worth it.

> Wait, doesn't HOTPLUG_CPU also depend on EXPERIMENTAL?

Damn, I started thinking about it, and then forgot about it when 
finishing the patch.

My thoughts were:
Is HOTPLUG_CPU still an experimental feature, or has it become a 
well-tested no longer experimental feature now that it's used on
most recent laptops?

> Stefan Richter

cu
Adrian

-- 

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