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Date: Mon, 30 Mar 2009 12:58:53 +0800
From: David Xu <davidxu@freebsd.org>
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To: Julian Elischer <julian@elischer.org>
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Cc: Scott Long <scottl@samsco.org>, Sergey Babkin <babkin@verizon.net>,
	freebsd-hackers@freebsd.org, attilio@freebsd.org,
	phk@phk.freebsd.dk, freebsd-current@freebsd.org, prashant.vaibhav@gmail.com
Subject: Re: Improving the kernel/i386
	timecounter	performance	(GSoC	proposal)
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Julian Elischer wrote:
> David Xu wrote:
>> David Xu wrote:
>>> Julian Elischer wrote:
>>>
>>>> depends on the hardware.
>>>> anyhow I was only saying it was possible, not necessarily
>>>> good or even useful.
>>>>
>>>>
>>>
>>> I had done some works for thread private page shared by kernel
>>> and userland when I was doing userland spinlock, if userland asks
>>> a page, kernel will allocate it and put some interesting thing in
>>> it by scheduler etcs, these code may be useful.
>>>
>> FYI:
>> http://people.freebsd.org/~davidxu/schedctl/
> 
> reading this quickly, you allocate a separately addressed page for
> each thread, but,  how do you use it?
> 
> 
I store the address in userland TLS area, then get it when I want to
check some scheduling informations.