From: Steven Rostedt <rostedt@goodmis.org>
To: Todd Brandt <todd.e.brandt@linux.intel.com>
Cc: linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org,
len.brown@intel.com, todd.e.brandt@intel.com
Subject: Re: [BUG] function_graph trace causes hang when using sleepgraph (4.15.0-rc1 and newer)
Date: Mon, 8 Jan 2018 20:07:56 -0500 [thread overview]
Message-ID: <20180108200756.08712bb4@vmware.local.home> (raw)
In-Reply-To: <1515459749.17761.10.camel@linux.intel.com>
On Mon, 08 Jan 2018 17:02:29 -0800
Todd Brandt <todd.e.brandt@linux.intel.com> wrote:
> Stephen, the problem is reversed by removing the following two commits,
> the one the bisect showed and the very next. So the problem is here:
>
> commit 1a149d7d3f45d311da1f63473736c05f30ae8a75
> Author: Steven Rostedt (VMware) <rostedt@goodmis.org>
> Date: Fri Sep 22 16:59:02 2017 -0400
>
> ring-buffer: Rewrite trace_recursive_(un)lock() to be simpler
This one still doesn't make sense, for why it would cause the hang.
> commit 12ecef0cb12102d8c034770173d2d1363cb97d52
> Author: Steven Rostedt (VMware) <rostedt@goodmis.org>
> Date: Thu Sep 21 16:22:49 2017 -0400
>
> tracing: Reverse the order of trace_types_lock and event_mutex
This one does.
Can you run lockdep when you do this and see if lockdep catches
anything? If it does, it should point directly to where the inversed
locking happened.
-- Steve
next prev parent reply other threads:[~2018-01-09 1:08 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-01-08 23:55 [BUG] function_graph trace causes hang when using sleepgraph (4.15.0-rc1 and newer) Todd Brandt
2018-01-09 1:02 ` Todd Brandt
2018-01-09 1:07 ` Steven Rostedt [this message]
2018-01-09 1:25 ` Todd Brandt
2018-01-09 3:07 ` Todd Brandt
2018-01-09 16:13 ` Steven Rostedt
2018-01-11 0:21 ` Todd Brandt
2018-01-18 17:21 ` Todd Brandt
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=20180108200756.08712bb4@vmware.local.home \
--to=rostedt@goodmis.org \
--cc=len.brown@intel.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-pm@vger.kernel.org \
--cc=todd.e.brandt@intel.com \
--cc=todd.e.brandt@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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox