All of lore.kernel.org
 help / color / mirror / Atom feed
From: Milian Wolff <milian.wolff@kdab.com>
To: Jiri Olsa <jolsa@redhat.com>
Cc: ahmadkhorrami <ahmadkhorrami@ut.ac.ir>,
	Steven Rostedt <rostedt@goodmis.org>,
	Arnaldo Carvalho de Melo <acme@redhat.com>,
	Linux-trace Users <linux-trace-users@vger.kernel.org>,
	Peter Zijlstra <peterz@infradead.org>,
	linux-trace-users-owner@vger.kernel.org,
	Jin Yao <yao.jin@linux.intel.com>,
	Namhyung Kim <namhyung@kernel.org>,
	Andi Kleen <ak@linux.intel.com>
Subject: Re: Wrong Perf Backtraces
Date: Mon, 30 Mar 2020 08:09:53 +0200	[thread overview]
Message-ID: <2522580.mvXUDI8C0e@agathebauer> (raw)
In-Reply-To: <20200329192010.GA2361248@krava>

[-- Attachment #1: Type: text/plain, Size: 1731 bytes --]

On Sonntag, 29. März 2020 21:20:10 CEST Jiri Olsa wrote:
> On Sun, Mar 29, 2020 at 03:50:57PM +0200, Milian Wolff wrote:
> > On Sonntag, 29. März 2020 14:39:33 CEST ahmadkhorrami wrote:
> > > Thanks. I did both of your changes. Perhaps some outputs are revised.
> > > But I still have repeated function calls and the script detects them.
> > 
> > > Here is one of them when the sampling period is 1000 events:
> > <snip>
> > 
> > > Here, we have two consecutive "7f91788120b5
> > > gtk_widget_propagate_state+0x195
> > > (/usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.30) gtkwidget.c:0" lines,
> > > while "gtk_widget_propagate_state+0x195" is not recursive. It should
> > > call "gtk_container_forall", which does not occur even after the second
> > > (inner) call.
> > 
> > Potentially you are just lacking some debug symbols here for this GTK
> > library. note that "gtkwidget.c:0" is bogus already - the line numbers
> > start with 1, so
> could we just skip those then? pass on all zero lined inlines
> and not add/display them

I guess so - but quite frankly I'm a bit uneasy to do this without further 
exploration about the actual causes here. Afaik DWARF does not say anything 
about the validity, so in theory there might be some language/compiler that 
encodes valid DWARF locations with line 0?

Generally, it would be quite interesting to figure out why there is /some/ 
DWARF data here such that the code thinks it's able to decode the inline frame 
but then fails and leads to this confusing result?

Cheers
-- 
Milian Wolff | milian.wolff@kdab.com | Senior Software Engineer
KDAB (Deutschland) GmbH, a KDAB Group company
Tel: +49-30-521325470
KDAB - The Qt, C++ and OpenGL Experts

[-- Attachment #2: smime.p7s --]
[-- Type: application/pkcs7-signature, Size: 3826 bytes --]

  reply	other threads:[~2020-03-30  6:10 UTC|newest]

Thread overview: 67+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <157597d74ff17f781d9de7e7e3defd13@ut.ac.ir>
2020-03-22 20:24 ` Wrong Perf Backtraces ahmadkhorrami
2020-03-23  0:34   ` Steven Rostedt
     [not found]     ` <21b3df4080709f193d62b159887e2a83@ut.ac.ir>
2020-03-23  8:49       ` Jiri Olsa
2020-03-23 10:03         ` ahmadkhorrami
2020-03-25 15:18           ` ahmadkhorrami
2020-03-25 15:46             ` Jiri Olsa
2020-03-25 18:54               ` ahmadkhorrami
2020-03-25 18:58               ` Arnaldo Carvalho de Melo
2020-03-25 19:10                 ` ahmadkhorrami
2020-03-25 19:28                   ` Arnaldo Carvalho de Melo
2020-03-25 20:01                     ` ahmadkhorrami
2020-03-25 20:39                       ` Jiri Olsa
2020-03-25 21:02                         ` Jiri Olsa
2020-03-25 21:09                           ` Steven Rostedt
2020-03-25 21:37                             ` ahmadkhorrami
2020-03-25 21:46                               ` Jiri Olsa
2020-03-25 22:21                                 ` ahmadkhorrami
2020-03-25 23:09                                   ` ahmadkhorrami
2020-03-26  9:59                                     ` Jiri Olsa
2020-03-26 13:20                                       ` ahmadkhorrami
2020-03-26 15:39                                         ` Jiri Olsa
2020-03-26 18:19                                           ` ahmadkhorrami
2020-03-26 18:21                                             ` ahmadkhorrami
2020-03-27  9:20                                             ` Jiri Olsa
2020-03-27 10:59                                               ` ahmadkhorrami
2020-03-27 11:04                                                 ` ahmadkhorrami
2020-03-27 12:10                                                   ` Milian Wolff
2020-03-27 12:58                                                     ` ahmadkhorrami
2020-03-27 13:25                                                       ` Milian Wolff
2020-03-27 13:33                                                         ` ahmadkhorrami
2020-03-27 18:43                                                   ` ahmadkhorrami
2020-03-27 22:37                                                     ` Jiri Olsa
2020-03-27 23:12                                                       ` ahmadkhorrami
2020-03-28 23:34                                                         ` Jiri Olsa
2020-03-29  0:43                                                           ` ahmadkhorrami
2020-03-29  1:16                                                             ` ahmadkhorrami
2020-03-29 11:19                                                               ` Jiri Olsa
2020-03-29 11:52                                                                 ` ahmadkhorrami
2020-03-29 12:08                                                                   ` Jiri Olsa
2020-03-29 12:39                                                                     ` ahmadkhorrami
2020-03-29 13:50                                                                       ` Milian Wolff
2020-03-29 14:23                                                                         ` ahmadkhorrami
2020-03-29 19:20                                                                         ` Jiri Olsa
2020-03-30  6:09                                                                           ` Milian Wolff [this message]
2020-03-30 13:07                                                                             ` Jiri Olsa
2020-03-30 13:49                                                                               ` ahmadkhorrami
2020-03-30 19:05                                                                                 ` ahmadkhorrami
2020-03-30 21:05                                                                                   ` debuginfod-based dwarf downloading, was " Frank Ch. Eigler
2020-03-31  9:26                                                                                     ` Jiri Olsa
2020-03-31 14:00                                                                                       ` Frank Ch. Eigler
2020-03-31  4:43                                                                                   ` ahmadkhorrami
2020-03-31  9:30                                                                                     ` Jiri Olsa
2020-03-31 11:53                                                                                       ` ahmadkhorrami
2020-03-31 12:43                                                                                   ` ahmadkhorrami
2020-03-31 13:20                                                                                     ` Jiri Olsa
2020-03-31 13:39                                                                                       ` ahmadkhorrami
2020-03-31 14:44                                                                                         ` Milian Wolff
2020-03-31 15:02                                                                                           ` ahmadkhorrami
2020-03-31 15:05                                                                                             ` ahmadkhorrami
2020-03-31 15:29                                                                                             ` Milian Wolff
2020-03-31 16:10                                                                                               ` Arnaldo Carvalho de Melo
2020-03-31 19:20                                                                                                 ` ahmadkhorrami
2020-03-31 19:17                                                                                               ` ahmadkhorrami
2020-03-31 20:57                                                                                               ` ahmadkhorrami
2020-04-04  1:01                                                                                                 ` ahmadkhorrami
2020-04-11 16:42                                                                                                   ` ahmadkhorrami
2020-04-11 21:04                                                                                                     ` ahmadkhorrami

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=2522580.mvXUDI8C0e@agathebauer \
    --to=milian.wolff@kdab.com \
    --cc=acme@redhat.com \
    --cc=ahmadkhorrami@ut.ac.ir \
    --cc=ak@linux.intel.com \
    --cc=jolsa@redhat.com \
    --cc=linux-trace-users-owner@vger.kernel.org \
    --cc=linux-trace-users@vger.kernel.org \
    --cc=namhyung@kernel.org \
    --cc=peterz@infradead.org \
    --cc=rostedt@goodmis.org \
    --cc=yao.jin@linux.intel.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.