From: "Naveen N. Rao" <naveen.n.rao@linux.vnet.ibm.com>
To: Catalin Marinas <catalin.marinas@arm.com>,
Jonathan Corbet <corbet@lwn.net>,
Jisheng Zhang <Jisheng.Zhang@synaptics.com>,
Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>,
"linux-doc@vger.kernel.org" <linux-doc@vger.kernel.org>,
Peter Zijlstra <peterz@infradead.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
Steven Rostedt <rostedt@goodmis.org>,
Thomas Gleixner <tglx@linutronix.de>,
"linux-arm-kernel@lists.infradead.org"
<linux-arm-kernel@lists.infradead.org>
Subject: Re: [PATCH v5] arm64: implement KPROBES_ON_FTRACE
Date: Thu, 22 Aug 2019 17:22:42 +0530 [thread overview]
Message-ID: <1566474733.p35psfjpl2.naveen@linux.ibm.com> (raw)
In-Reply-To: <20190822191351.3796aca8@xhacker.debian>
Jisheng Zhang wrote:
> KPROBES_ON_FTRACE avoids much of the overhead with regular kprobes as it
> eliminates the need for a trap, as well as the need to emulate or
> single-step instructions.
>
> Tested on berlin arm64 platform.
>
> ~ # mount -t debugfs debugfs /sys/kernel/debug/
> ~ # cd /sys/kernel/debug/
> /sys/kernel/debug # echo 'p _do_fork' > tracing/kprobe_events
>
> before the patch:
>
> /sys/kernel/debug # cat kprobes/list
> ffffff801009fe28 k _do_fork+0x0 [DISABLED]
>
> after the patch:
>
> /sys/kernel/debug # cat kprobes/list
> ffffff801009ff54 k _do_fork+0x4 [DISABLED][FTRACE]
>
> Signed-off-by: Jisheng Zhang <Jisheng.Zhang@synaptics.com>
Reviewed-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
- Naveen
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next prev parent reply other threads:[~2019-08-22 11:53 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-08-22 11:25 [PATCH v5] arm64: implement KPROBES_ON_FTRACE Jisheng Zhang
2019-08-22 11:52 ` Naveen N. Rao [this message]
2019-08-23 14:57 ` Masami Hiramatsu
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=1566474733.p35psfjpl2.naveen@linux.ibm.com \
--to=naveen.n.rao@linux.vnet.ibm.com \
--cc=Jisheng.Zhang@synaptics.com \
--cc=catalin.marinas@arm.com \
--cc=corbet@lwn.net \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-doc@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mark.rutland@arm.com \
--cc=mhiramat@kernel.org \
--cc=peterz@infradead.org \
--cc=rostedt@goodmis.org \
--cc=tglx@linutronix.de \
/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).