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Subject: Re: [RFC, 6/7] NUMA hotplug emulator
From: Dave Hansen <dave@linux.vnet.ibm.com>
To: Andi Kleen <ak@linux.intel.com>
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On Tue, 2010-05-18 at 10:55 +0200, Andi Kleen wrote:
> I liked Dave's earlier proposal to do a command line parameter like interface
> for "probe". Perhaps that can be done. It shouldn't need a lot of code.

After looking at the code, configfs doesn't look to me like it can be
done horribly easily.  It takes a least a subsystem and then a few
structures to get things up and running.  There also doesn't appear to
be a good subsystem to plug into.

> In fact there are already two different parser libraries for this:
> lib/parser.c and lib/params.c. One could chose the one that one likes
> better :-)

Agreed.  But, I do see why Greg is suggesting configfs here.
Superficially, it seems like a good configfs fit, but I think configfs
is only a good fit when you need to cram a _bunch_ of stuff into a _new_
interface.  Here, we have a relatively tiny amount of data that has half
of what it needs from an existing interface.  

-- Dave