From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E7B561BB6BE; Mon, 9 Sep 2024 13:56:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725890179; cv=none; b=jPBQEMzL3OxJD1DYU5byqjjLat8doVgeKnXXhVLrvVSdnRo8joon7q/oRhstQBTiQadj3mRX8yUhqyHV6LN16gQ7mCduyuhGjGVtCkw1Neaplvn6qLYlnw/2oHH0yRZhDWWVvDTcincdn929P3jJv5ZJXowkMYUJIiHlUJniaoA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725890179; c=relaxed/simple; bh=ziCNmukqSoa9NT917TReyruuvMtETI5Xgy5zWsDcB/o=; h=Date:From:To:Cc:Subject:Message-Id:In-Reply-To:References: Mime-Version:Content-Type; b=G+YcrGQQmmDuD88l2bNnvTomAW3QIe9QESOMCSMD60AZf6u4QPxG3jCCMuoH76BY4i54mp/8fOMU9iDS07Cf0mUUETsQdmQ0TJy79PGZHFIwati/lSCPi21hZJj1nmJXEvBlOplK9bkO55SbncppnJ30AOFawdShC4VPivzr8I8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=T+8areK0; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="T+8areK0" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D1AEEC4CEC5; Mon, 9 Sep 2024 13:56:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1725890178; bh=ziCNmukqSoa9NT917TReyruuvMtETI5Xgy5zWsDcB/o=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=T+8areK0Mx0oT7YCzbvUb849ygLqRMa624fTVjsD1OBpI9HgfkOEKNDjmRC8XVTMX xsEto2R9oBzNulxYD2t2Mq5gtqy7dven94GQJTW+7o+7JcaS0FCXUH1c/tnrCCgYoy 2Xsd5XUwwFvQR1flLKZGBnQSbFHe2w0chsEvmrICU73W4TVJMIXm/mYafwEKe54H6k z3Nl0tvAFYvOmPgnfJcxF2tuk9lPDqupRj2Lk7WRzocwOvYJmrpcTC2GBC1oFk8gC+ 8i1Urcje+93yzV007O16IOZcjSN09MvU4oeAEcNT/GdAaUD/redY0jr3Vvk32eBuaP 69T07pFDbEiOg== Date: Mon, 9 Sep 2024 22:56:14 +0900 From: Masami Hiramatsu (Google) To: Sven Schnelle Cc: Zheng Yejian , Steven Rostedt , Mark Rutland , Mathieu Desnoyers , linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org Subject: Re: [PATCH 5/7] tracing: add config option for print arguments in ftrace Message-Id: <20240909225614.4f6d022e58f1276113c8492b@kernel.org> In-Reply-To: References: <20240904065908.1009086-1-svens@linux.ibm.com> <20240904065908.1009086-6-svens@linux.ibm.com> <69b78634-3295-c22e-c09c-e41aa4554df3@huaweicloud.com> <20240908223048.8bd6961dbc741d971f57b5c2@kernel.org> X-Mailer: Sylpheed 3.7.0 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Mon, 09 Sep 2024 10:16:55 +0200 Sven Schnelle wrote: > Masami Hiramatsu (Google) writes: > > > On Fri, 6 Sep 2024 11:36:11 +0800 > > Zheng Yejian wrote: > > > >> On 2024/9/4 14:58, Sven Schnelle wrote: > >> > Add a config option to disable/enable function argument > >> > printing support during runtime. > >> > > >> > Signed-off-by: Sven Schnelle > >> > --- > >> > kernel/trace/Kconfig | 12 ++++++++++++ > >> > 1 file changed, 12 insertions(+) > >> > > >> > diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig > >> > index 721c3b221048..8b9b6cdf39ac 100644 > >> > --- a/kernel/trace/Kconfig > >> > +++ b/kernel/trace/Kconfig > >> > @@ -242,6 +242,18 @@ config FUNCTION_GRAPH_RETVAL > >> > enable it via the trace option funcgraph-retval. > >> > See Documentation/trace/ftrace.rst > >> > > >> > +config FUNCTION_TRACE_ARGS > >> > + bool "Kernel Function Tracer Arguments" > >> > + depends on HAVE_FUNCTION_ARG_ACCESS_API > >> > + depends on DEBUG_INFO_BTF && BPF_SYSCALL > >> > >> Nice feature! > >> > >> Just a nit, DEBUG_INFO_BTF currently depends on BPF_SYSCALL, > >> so BPF_SYSCALL may not be necessary here. This feature > >> also doesn't seem to depend on bpf. > > > > Indeed. Sven, you can check the PROBE_EVENTS_BTF_ARGS as > > an example. > > > > config PROBE_EVENTS_BTF_ARGS > > depends on HAVE_FUNCTION_ARG_ACCESS_API > > depends on FPROBE_EVENTS || KPROBE_EVENTS > > depends on DEBUG_INFO_BTF && BPF_SYSCALL > > bool "Support BTF function arguments for probe events" > > Now i'm confused - Zheng wrote that DEBUG_INFO_BTF depends on > BPF_SYSCALL. I just verified that. So i could just remove BPF_SYSCALL > from the dependencies - but your example also has BPF_SYSCALL listed. Ah, sorry for confusion. In this case, just need DEBUG_INFO_BTF. Hmm, I think I also need to remove BPF_SYSCALL. Thanks, > > Regards > Sven -- Masami Hiramatsu (Google)