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Date: Tue, 25 Mar 2014 10:50:01 -0700
From: Dave Hansen <dave.hansen@intel.com>
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To: "Kirill A. Shutemov" <kirill@shutemov.name>,
 Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Subject: Re: [PATCH 1/1] mm: move FAULT_AROUND_ORDER to arch/
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Cc: linux-arch@vger.kernel.org, riel@redhat.com, rusty@rustcorp.com.au,
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On 03/25/2014 10:36 AM, Kirill A. Shutemov wrote:
>> > +/*
>> > + * Fault around order is a control knob to decide the fault around pages.
>> > + * Default value is set to 0UL (disabled), but the arch can override it as
>> > + * desired.
>> > + */
>> > +#ifndef FAULT_AROUND_ORDER
>> > +#define FAULT_AROUND_ORDER	0UL
>> > +#endif
> FAULT_AROUND_ORDER == 0 case should be handled separately in
> do_read_fault(): no reason to go to do_fault_around() if we are going to
> fault in only one page.

Isn't this the kind of thing we want to do in Kconfig?