From: David Daney <ddaney@caviumnetworks.com>
To: rostedt@goodmis.org
Cc: wuzhangjin@gmail.com, linux-kernel@vger.kernel.org,
linux-mips@linux-mips.org, Thomas Gleixner <tglx@linutronix.de>,
Ralf Baechle <ralf@linux-mips.org>,
Nicholas Mc Guire <der.herr@hofr.at>
Subject: Re: [PATCH -v4 9/9] tracing: add function graph tracer support for MIPS
Date: Thu, 22 Oct 2009 09:16:25 -0700 [thread overview]
Message-ID: <4AE08559.40806@caviumnetworks.com> (raw)
In-Reply-To: <1256227916.20866.784.camel@gandalf.stny.rr.com>
Steven Rostedt wrote:
> On Thu, 2009-10-22 at 08:59 -0700, David Daney wrote:
>
>> This is what I was talking about up-thread. Leaf functions may have no
>> function prolog. If you do code scanning you will fail. While scanning
>> backwards, there is no way to know when you have entered a new function.
>> Looking for function return sequences 'jr ra' doesn't work as there
>> may be functions with multiple return sites, functions that never
>> return, or arbitrary data before the function. I think you have to
>> force a frame pointer to be established if you want this to work.
>
> Functions that run off into another function?? I guess the compiler
> could do that, but with -pg enable, I would think is broken.
>
Use of GCC-4.5's __builtin_unreachable() can lead to this, as well as
functions that call noreturn functions.
Note to self: Time to resend the __builtin_unreachable() patch set again...
David Daney
next prev parent reply other threads:[~2009-10-22 16:17 UTC|newest]
Thread overview: 63+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <cover.1256135456.git.wuzhangjin@gmail.com>
2009-10-21 14:34 ` [PATCH -v4 1/9] tracing: convert trace_clock_local() as weak function Wu Zhangjin
2009-10-21 14:34 ` [PATCH -v4 2/9] MIPS: add mips_timecounter_read() to get high precision timestamp Wu Zhangjin
2009-10-21 14:34 ` [PATCH -v4 3/9] tracing: add MIPS specific trace_clock_local() Wu Zhangjin
2009-10-21 14:46 ` Steven Rostedt
2009-10-21 15:11 ` Wu Zhangjin
2009-10-21 14:34 ` [PATCH -v4 4/9] tracing: add static function tracer support for MIPS Wu Zhangjin
2009-10-21 15:24 ` Steven Rostedt
2009-10-22 17:47 ` Wu Zhangjin
2009-10-22 17:59 ` Steven Rostedt
2009-10-22 18:34 ` Wu Zhangjin
2009-10-22 18:34 ` David Daney
2009-10-22 19:13 ` Wu Zhangjin
[not found] ` <19168.49354.525249.654494@ropi.home>
2009-10-22 20:52 ` Steven Rostedt
2009-10-22 21:09 ` Frederic Weisbecker
2009-10-22 21:29 ` Adam Nemet
2009-10-22 21:55 ` Steven Rostedt
2009-10-23 1:09 ` Wu Zhangjin
2009-10-22 22:17 ` Richard Sandiford
2009-10-23 9:32 ` Wu Zhangjin
2009-10-23 22:48 ` [PATCH] MIPS: Add option to pass return address location to _mcount. Was: " David Daney
2009-10-24 9:12 ` Richard Sandiford
2009-10-24 15:53 ` Wu Zhangjin
2009-10-26 19:08 ` [PATCH] MIPS: Add option to pass return address location to _mcount David Daney
2009-10-27 1:04 ` Wu Zhangjin
2009-10-27 21:20 ` Richard Sandiford
2009-10-29 6:44 ` Wu Zhangjin
2009-10-29 16:32 ` David Daney
2009-10-29 18:11 ` David Daney
2009-10-23 7:21 ` [PATCH -v4 4/9] tracing: add static function tracer support for MIPS Wu Zhangjin
2009-10-21 14:34 ` [PATCH -v4 5/9] tracing: enable HAVE_FUNCTION_TRACE_MCOUNT_TEST " Wu Zhangjin
2009-10-21 14:35 ` [PATCH -v4 6/9] tracing: add an endian argument to scripts/recordmcount.pl Wu Zhangjin
2009-10-21 15:26 ` Steven Rostedt
2009-10-21 14:35 ` [PATCH -v4 7/9] tracing: add dynamic function tracer support for MIPS Wu Zhangjin
2009-10-21 14:35 ` [PATCH -v4 8/9] tracing: not trace mips_timecounter_init() in MIPS Wu Zhangjin
2009-10-21 14:35 ` [PATCH -v4 9/9] tracing: add function graph tracer support for MIPS Wu Zhangjin
2009-10-21 15:21 ` Wu Zhangjin
2009-10-21 16:14 ` Steven Rostedt
2009-10-21 16:12 ` Steven Rostedt
2009-10-21 16:37 ` David Daney
2009-10-21 16:46 ` Steven Rostedt
2009-10-21 17:07 ` David Daney
2009-10-21 17:23 ` Steven Rostedt
2009-10-21 17:48 ` David Daney
2009-10-21 18:09 ` Steven Rostedt
2009-10-21 18:17 ` Nicholas Mc Guire
2009-10-21 18:34 ` Steven Rostedt
2009-10-21 18:25 ` David Daney
2009-10-22 11:38 ` Wu Zhangjin
2009-10-22 13:17 ` Steven Rostedt
2009-10-22 13:31 ` Wu Zhangjin
2009-10-22 15:20 ` Steven Rostedt
2009-10-22 15:59 ` David Daney
2009-10-22 16:11 ` Steven Rostedt
2009-10-22 16:16 ` David Daney [this message]
2009-10-22 18:00 ` Steven Rostedt
2009-10-22 17:39 ` Wu Zhangjin
2009-10-22 17:58 ` Steven Rostedt
[not found] ` <26008418.post@talk.nabble.com>
2009-10-25 10:48 ` Wu Zhangjin
2009-10-25 10:48 ` Wu Zhangjin
2009-10-25 13:37 ` Patrik Kluba
2009-10-25 13:37 ` Patrik Kluba
2009-10-25 14:22 ` Wu Zhangjin
2009-10-25 15:55 ` Richard Sandiford
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=4AE08559.40806@caviumnetworks.com \
--to=ddaney@caviumnetworks.com \
--cc=der.herr@hofr.at \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mips@linux-mips.org \
--cc=ralf@linux-mips.org \
--cc=rostedt@goodmis.org \
--cc=tglx@linutronix.de \
--cc=wuzhangjin@gmail.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).