From: Steven Rostedt <rostedt@goodmis.org>
To: "Leonardo Brás" <leobras@redhat.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
Masami Hiramatsu <mhiramat@kernel.org>,
Thomas Gleixner <tglx@linutronix.de>,
Yury Norov <yury.norov@gmail.com>,
"Paul E. McKenney" <paulmck@kernel.org>,
"Peter Zijlstra (Intel)" <peterz@infradead.org>,
Nadav Amit <namit@vmware.com>,
Zhen Lei <thunder.leizhen@huawei.com>,
Chen Zhongjin <chenzhongjin@huawei.com>,
linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org,
Marcelo Tosatti <mtosatti@redhat.com>
Subject: Re: [RFC PATCH 1/1] smp: Add tracepoints for functions called with smp_call_function*()
Date: Thu, 6 Apr 2023 09:49:47 -0400 [thread overview]
Message-ID: <20230406094947.6b92084c@gandalf.local.home> (raw)
In-Reply-To: <cf8d18d80222c561da1865514734d92e0e2fb3d5.camel@redhat.com>
On Thu, 06 Apr 2023 05:42:13 -0300
Leonardo Brás <leobras@redhat.com> wrote:
> Hello Sebastian, thanks for the heads up!
>
> IIUC Valentin is adding/improving tracepoints that are collected in the
> requesting CPU, at the moment of scheduling the IPI, which are also useful.
>
> But on my scenario, would be nice to actually have the information on the time
> window in which the requested function is running in the requested CPU.
>
Well once you know the functions that are being called (running your test
case with the IPI trace events), then you can get the timings of those same
functions by:
# cd /sys/kernel/tracing
# echo '<space-delimited-list-of-functions>' > set_ftrace_filter
# echo function_graph > current_tracer
Then the function graph will give you those timings.
-- Steve
next prev parent reply other threads:[~2023-04-06 13:50 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-04-06 7:57 [RFC PATCH 1/1] smp: Add tracepoints for functions called with smp_call_function*() Leonardo Bras
2023-04-06 8:15 ` Sebastian Andrzej Siewior
2023-04-06 8:42 ` Leonardo Brás
2023-04-06 13:49 ` Steven Rostedt [this message]
2023-04-19 4:04 ` Leonardo Brás
2023-04-06 9:55 ` Peter Zijlstra
2023-04-19 3:45 ` Leonardo Brás
2023-05-03 4:23 ` Leonardo Brás
2023-05-03 14:59 ` Peter Zijlstra
2023-05-03 15:53 ` Leonardo Bras Soares Passos
2023-05-04 11:59 ` Valentin Schneider
2023-05-04 13:34 ` Steven Rostedt
2023-05-04 15:01 ` Peter Zijlstra
2023-05-10 20:27 ` Leonardo Brás
2023-05-10 22:18 ` Leonardo Bras Soares Passos
2023-05-10 23:05 ` Leonardo Bras Soares Passos
2023-05-11 8:13 ` Valentin Schneider
2023-05-11 9:25 ` Leonardo Bras Soares Passos
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=20230406094947.6b92084c@gandalf.local.home \
--to=rostedt@goodmis.org \
--cc=bigeasy@linutronix.de \
--cc=chenzhongjin@huawei.com \
--cc=leobras@redhat.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-trace-kernel@vger.kernel.org \
--cc=mhiramat@kernel.org \
--cc=mtosatti@redhat.com \
--cc=namit@vmware.com \
--cc=paulmck@kernel.org \
--cc=peterz@infradead.org \
--cc=tglx@linutronix.de \
--cc=thunder.leizhen@huawei.com \
--cc=yury.norov@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).