This is the mail archive of the
systemtap@sourceware.org
mailing list for the systemtap project.
Re: Discussion at Linux Foundation Japan Symposium
- From: KOSAKI Motohiro <kosaki dot motohiro at jp dot fujitsu dot com>
- To: prasad at linux dot vnet dot ibm dot com
- Cc: kosaki dot motohiro at jp dot fujitsu dot com, Jun Koi <junkoi2004 at gmail dot com>, Satoshi OSHIMA <satoshi dot oshima dot fk at hitachi dot com>, systemtap at sourceware dot org, mhiramat at redhat dot com, hisashi dot hashimoto dot wh at hitachi dot com, Yumiko SUGITA <yumiko dot sugita dot yf at hitachi dot com>
- Date: Thu, 18 Dec 2008 18:57:57 +0900 (JST)
- Subject: Re: Discussion at Linux Foundation Japan Symposium
- References: <20081218181653.97C0.KOSAKI.MOTOHIRO@jp.fujitsu.com> <20081218094539.GA4846@in.ibm.com>
> > Of cource, this approach indicate systemtap lost some feature.
> > (e.g. above section don't have line number information and local
> > variable name information)
> >
> > but it is still useful for average tracing user.
> >
> I'm not sure if the issue is discussed without being aware of the
> dwarfless probing that's available in SystemTap since a while ago. More
> details at: http://sourceware.org/systemtap/wiki/MakeDoWithoutDebugInfo
Cool.
but, I feel "must asmlinkage" is too strong restriction.
Now, ftrace can trace any function by -pg compile option and
self modification code.
Can we do the same thing?
I think ftrace approach have very few performance degression and
we can apply production kernel.