From: compudj@krystal.dyndns.org (Mathieu Desnoyers)
Subject: [ltt-dev] simple userspace tracing with LTTng 0.9.10
Date: Thu, 29 Jan 2009 14:30:38 -0500 [thread overview]
Message-ID: <20090129193038.GA13755@Krystal> (raw)
In-Reply-To: <1E65288790442545B413D69F2A8D27DE046A31F5@ERLD164A.ww004.siemens.net>
* Akyurek, Ali (EXT) (ali.akyurek.ext at siemens.com) wrote:
>
> Hi,
>
> Since there is no specialized trace concept in legacy LTTng 0.9.10,
>
> I'm thinking of defining a new marker and use it as below. I think this would be ok, but it'll require many additions.
>
> What if i use an existing trace_mark like kernel_printk below, instead of defining a new marker.
> I know this is ugly and tricky, but can i make it work?
>
> Thanks.
>
>
>
> static ssize_t write_event(struct file *file, const char __user *user_buf,
> size_t count, loff_t *ppos)
> {
> .
> ..
> ...
> - marker = &GET_MARKER(userspace, event);
> - ltt_specialized_trace(marker, marker->single.probe_private,
> - page, count + 1, sizeof(char));
>
> + trace_mark(userspace_event,"%s",string_from_user_buf);
>
Never pass a __user pointer to a marker. First do a copy_from_user.
Mathieu
> ...
> ..
> .
> }
>
>
>
> -----Urspr?ngliche Nachricht-----
> Von: Mathieu Desnoyers [mailto:compudj at krystal.dyndns.org]
> Gesendet: Mittwoch, 28. Januar 2009 16:57
> An: Akyurek, Ali (EXT)
> Cc: ltt-dev at lists.casi.polymtl.ca
> Betreff: Re: [ltt-dev] simple userspace tracing with LTTng 0.9.10
>
> * Akyurek, Ali (EXT) (ali.akyurek.ext at siemens.com) wrote:
> > Hi all,
> >
> > I've used simple userspace event tracing with the latest version by
> > writing to the mnt/debugfs/ltt/write_event.
> > But now i'm using an old LTTng (because i have to), 0.9.10.
> >
> > Is it possible to port this simple uspace tracing feature to the old
> > lttng versions?
> >
> > Or it is not possible because of some architectural restrictions of
> > kernel or LTTng?
> > Thanks.
> >
>
> That should be easily doable, as long as you have a kernel with debugfs.
>
> The main patch concerned is :
> lttng-userspace-write-event.patch
>
> Mathieu
>
> > _______________________________________________
> > ltt-dev mailing list
> > ltt-dev at lists.casi.polymtl.ca
> > http://lists.casi.polymtl.ca/cgi-bin/mailman/listinfo/ltt-dev
> >
>
> --
> Mathieu Desnoyers
> OpenPGP key fingerprint: 8CD5 52C3 8E3C 4140 715F BA06 3F25 A8FE 3BAE 9A68
>
--
Mathieu Desnoyers
OpenPGP key fingerprint: 8CD5 52C3 8E3C 4140 715F BA06 3F25 A8FE 3BAE 9A68
prev parent reply other threads:[~2009-01-29 19:30 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-01-26 18:44 Akyurek, Ali (EXT)
2009-01-28 15:56 ` Mathieu Desnoyers
2009-01-29 18:02 ` Akyurek, Ali (EXT)
2009-01-29 19:30 ` Mathieu Desnoyers [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20090129193038.GA13755@Krystal \
--to=compudj@krystal.dyndns.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox