lttng-dev.lists.lttng.org archive mirror
 help / color / mirror / Atom feed
From: Mathieu Desnoyers via lttng-dev <lttng-dev@lists.lttng.org>
To: Evan Galea <evanjamesgalea@gmail.com>
Cc: lttng-dev <lttng-dev@lists.lttng.org>
Subject: Re: [lttng-dev] unable to add callstack-user context
Date: Fri, 9 Jul 2021 09:54:35 -0400 (EDT)	[thread overview]
Message-ID: <482770069.11167.1625838875359.JavaMail.zimbra@efficios.com> (raw)
In-Reply-To: <CAA+-46q3vLWvu6WNueSybHZ-7hE=S=eZo1WWXDDq7YOa7hyjWg@mail.gmail.com>


[-- Attachment #1.1: Type: text/plain, Size: 1731 bytes --]

----- On Jul 9, 2021, at 4:30 AM, lttng-dev <lttng-dev@lists.lttng.org> wrote: 

> Hi there, I'm a little new to lttng and tracing in general. I am using a Java
> Userspace agent, which is working well, but I am having trouble adding
> callstack context to my tracing channels. I'm not sure if it's relevant but
> running 'lttng add-context --list" shows callstack-user in the list.

It's not surprising, because the callstack-user context is specific to the kernel tracer. 

> the commands I input are:

> lttng create
> lttng enable-channel --userspace mychannel
> lttng enable-event --userspace --all --channel mychannel
> lttng add-context --userspace --channel mychannel --type callstack-user
> >Error: callstack-user: UST invalid context

This is expected. 

> When I run the following command instead:
> lttng add-context --userspace --channel mychannel --type vpid

> I am able to get it to work and I see vpid appear in my traces. Are there any
> other things I need to set up first to be able to use it?

> also, are there any commands that can list the per-domain contexts available?

Not currently, though I think it would make sense to make "lttng add-context --list" allow a tracing domain 
(e.g. --kernel/--userspace) to be specified as a future improvement. 

Some information about this is available in the lttng-add-context(1) man page, but the fact that the 
kernel and user callstack contexts are only supported by the kernel tracer don't seem to be mentioned. 

Thanks, 

Mathieu 

> _______________________________________________
> lttng-dev mailing list
> lttng-dev@lists.lttng.org
> https://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev

-- 
Mathieu Desnoyers 
EfficiOS Inc. 
http://www.efficios.com 

[-- Attachment #1.2: Type: text/html, Size: 3714 bytes --]

[-- Attachment #2: Type: text/plain, Size: 156 bytes --]

_______________________________________________
lttng-dev mailing list
lttng-dev@lists.lttng.org
https://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev

      reply	other threads:[~2021-07-09 13:54 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-07-09  8:30 [lttng-dev] unable to add callstack-user context Evan Galea via lttng-dev
2021-07-09 13:54 ` Mathieu Desnoyers via lttng-dev [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=482770069.11167.1625838875359.JavaMail.zimbra@efficios.com \
    --to=lttng-dev@lists.lttng.org \
    --cc=evanjamesgalea@gmail.com \
    --cc=mathieu.desnoyers@efficios.com \
    /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;
as well as URLs for NNTP newsgroup(s).