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Subject: Re: [PATCH V2 1/2] mm: move FAULT_AROUND_ORDER to arch/
From: David Miller <davem@davemloft.net>
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From: Dave Hansen <dave.hansen@intel.com>
Date: Fri, 04 Apr 2014 09:18:43 -0700

> On 04/03/2014 11:27 PM, Madhavan Srinivasan wrote:
>> This patch creates infrastructure to move the FAULT_AROUND_ORDER
>> to arch/ using Kconfig. This will enable architecture maintainers
>> to decide on suitable FAULT_AROUND_ORDER value based on
>> performance data for that architecture. Patch also adds
>> FAULT_AROUND_ORDER Kconfig element in arch/X86.
> 
> Please don't do it this way.
> 
> In mm/Kconfig, put
> 
> 	config FAULT_AROUND_ORDER
> 		int
> 		default 1234 if POWERPC
> 		default 4
> 
> The way you have it now, every single architecture that needs to enable
> this has to go put that in their Kconfig.  That's madness.  This way,
> you only put it in one place, and folks only have to care if they want
> to change the default to be something other than 4.

It looks more like it's necessary only to change the default, not
to enable it.  Unless I read his patch wrong...