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Date: Fri, 03 Jul 2009 14:19:09 -0500
From: Alan Cox <alc@cs.rice.edu>
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To: Robert Watson <rwatson@FreeBSD.org>
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Cc: freebsd-hackers@freebsd.org,
	Mel Flynn <mel.flynn+fbsd.hackers@mailing.thruhere.net>,
	Wojciech Puchar <wojtek@wojtek.tensor.gdynia.pl>
Subject: Re: large pages (amd64)
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Robert Watson wrote:
>
> On Tue, 30 Jun 2009, Mel Flynn wrote:
>
>>>> It looks like sys/kern/kern_proc.c could call mincore around the 
>>>> loop at line 1601 (rev 194498), but I know nothing about the vm 
>>>> subsystem to know the implications or locking involved. There's 
>>>> still 16 bytes of spare to consume, in the kve_vminfo struct though ;)
>>>
>>> Yes, to start with, you could replace the call to pmap_extract() 
>>> with a call to pmap_mincore() and export a Boolean to user space 
>>> that says, "This region of the address space contains one or more 
>>> superpage mappings."
>>
>> How about attached?
>
> I like the idea -- there are some style nits that need fixing though. 
> Assuming Alan is happy with the VM side of things, I can do the 
> cleanup and get it in the tree.

Aside from the style nits, it looks good to me.

Alan