Re: [PATCH] do not call trace_printk on non-debug build

From: Steven Rostedt <rostedt@goodmis.org>
To: Wei Wang <wvw@google.com>
Cc: gregkh@linuxfoundation.org, Wei Wang <wei.vince.wang@gmail.com>,
	Ingo Molnar <mingo@redhat.com>,
	Andrew Morton <akpm@linux-foundation.org>,
	Kees Cook <keescook@chromium.org>,
	Peter Zijlstra <peterz@infradead.org>,
	Thomas Gleixner <tglx@linutronix.de>, Crt Mori <cmo@melexis.com>,
	Alexei Starovoitov <ast@kernel.org>,
	Randy Dunlap <rdunlap@infradead.org>,
	linux-kernel@vger.kernel.org, Joe Perches <joe@perches.com>
Subject: Re: [PATCH] do not call trace_printk on non-debug build
Date: Thu, 26 Apr 2018 21:46:57 -0400	[thread overview]
Message-ID: <20180426214657.612623a3@gandalf.local.home> (raw)
In-Reply-To: <CAGXk5yo-9E7xOibMSWzPKgiduLrjzBA2+i0nhPNKiFnfyL7mUA@mail.gmail.com>

On Wed, 25 Apr 2018 04:53:33 +0000
Wei Wang <wvw@google.com> wrote:

> On Tue, Apr 24, 2018 at 12:26 PM Steven Rostedt <rostedt@goodmis.org> wrote:
> > A lot of kernel developers use trace_printk() and I want to make it as
> > easy to use as possible. I don't want to add a config to enable it,
> > because that would be something that could be rather annoying.  
> 
> > Let's add it to checkpatch and see if that can draining the swamp of
> > abusers.  
> 
> 
> Currently I see f2fs trace is using this when having CONFIG_F2FS_IO_TRACE,
> so I am not sure how checkpatch would work. How about we add a BUILD_BUG
> surrounded by a config which would let us flag abuse easily on build time?

I don't want a config to have to be set for adding this. That would
really irritate myself, as I constantly take configs from others for
debugging purposes and then slam trace_printk() all over the place. It
would be annoying to have to remember to enable a config. And having a
config would also change the way the kernel gets built, and for
debugging the less variables the better.

But you are correct. I see lots of abusers with trace_printk(). I think
it's time for me to start removing them.

-- Steve