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Date: Sat, 6 Mar 2010 09:39:17 +0100
From: Ulrich =?utf-8?B?U3DDtnJsZWlu?= <uqs@spoerlein.net>
To: Xin LI <delphij@delphij.net>
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	Alexander Best <alexbestms@wwu.de>, freebsd-hackers@freebsd.org
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Cc: Alexander Best <alexbestms@wwu.de>, freebsd-hackers@freebsd.org
Subject: Re: tiny lib/libkvm/kvm_proc.c correction
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On Fri, 05.03.2010 at 12:38:40 -0800, Xin LI wrote:
> On 2010/03/05 11:59, Alexander Best wrote:
> > Xin LI schrieb am 2010-03-05:
> > On 2010/03/05 11:26, Alexander Best wrote:
> >>>> hi there. does this look right?
> > 
> > Not to me, the value is not to be used this way and the comments
> > above the code explained the same thing.
> > 
> > I think we should use cputick2usec but it's not available to userland
> > (one have to copy cpu_tick_frequency and friends).
> > 
> >> damn you're right. i completely overlooked that comment. would it be worth
> >> making cputick2usec available to userland? is kvm_proc.c the only candidate in
> >> need of converting cpu ticks to usecs?
> 
> I'm not sure how to do that unfortunately, is there a way to expose a
> kernel variable to userland which also works on a crash dump?

ticks *is* available to libkvm, not sure what happens on crashdumps,
though. The following patchset has not been tested:

https://www.spoerlein.net/gitweb/?p=freebsd.work/.git;a=commitdiff;h=d500a051eb75dd234166bb11485c0a953aefce1d

Regards,
Uli