Date: Sat, 06 Mar 2010 11:51:13 +0100 (CET) From: Alexander Best <alexbestms@wwu.de> To: Ulrich =?iso-8859-1?Q?Sp=F6rlein?= <uqs@spoerlein.net>, Xin LI <delphij@delphij.net> Cc: freebsd-hackers@freebsd.org Subject: Re: tiny lib/libkvm/kvm_proc.c correction Message-ID: <permail-20100306105113f0889e8400004f37-a_best01@message-id.uni-muenster.de> In-Reply-To: <20100306083916.GI21344@acme.spoerlein.net>
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Ulrich Sp=F6rlein schrieb am 2010-03-06:
> 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:
very nice, but wouldn't it be better to define cputick2usec() somewhere els=
e
so other userland code can make use of it? even if right now libkvm is the
only source in need of such a conversion function, in the future other code
might benefit from userland cputick2usec(). now where would be a good place=
to
put this in?
alex
ps: did anybody look @ {net|open|dragonfly}bsd, linux, solaris, etc. so see=
if
they have a userland cputick2usec() and where it's defined?
> https://www.spoerlein.net/gitweb/?p=3Dfreebsd.work/.git;a=3Dcommitdiff;h=
=3Dd500a051eb75dd234166bb11485c0a953aefce1d
> Regards,
> Uli
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