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Date:   Wed, 31 May 2023 14:50:15 -0700
From:   Josh Poimboeuf <jpoimboe@kernel.org>
To:     Steven Rostedt <rostedt@goodmis.org>
Cc:     LKML <linux-kernel@vger.kernel.org>,
        Linux Trace Kernel <linux-trace-kernel@vger.kernel.org>,
        Masami Hiramatsu <mhiramat@kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Peter Zijlstra <peterz@infradead.org>,
        Mark Rutland <mark.rutland@arm.com>,
        Song Liu <song@kernel.org>, live-patching@vger.kernel.org,
        Kees Cook <keescook@chromium.org>,
        Miguel Ojeda <ojeda@kernel.org>,
        Nick Desaulniers <ndesaulniers@google.com>,
        Ingo Molnar <mingo@kernel.org>
Subject: Re: [PATCH] ftrace: Allow inline functions not inlined to be traced
Message-ID: <20230531215015.dxmkaouhdcat3hoe@treble>
References: <20230502164102.1a51cdb4@gandalf.local.home>
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On Tue, May 02, 2023 at 04:41:02PM -0400, Steven Rostedt wrote:
> Today, it is no longer a problem if an inlined function is not inlined and
> is traced. Removing notrace from inline has been requested several times
> over the years. I believe it is now safe to do so.
> 
> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
> ---
>  include/linux/compiler_types.h | 7 +++----
>  1 file changed, 3 insertions(+), 4 deletions(-)
> 
> diff --git a/include/linux/compiler_types.h b/include/linux/compiler_types.h
> index 547ea1ff806e..c8f23ba1c339 100644
> --- a/include/linux/compiler_types.h
> +++ b/include/linux/compiler_types.h
> @@ -182,9 +182,8 @@ struct ftrace_likely_data {
>   * externally visible function. This makes extern inline behave as per gnu89
>   * semantics rather than c99. This prevents multiple symbol definition errors
>   * of extern inline functions at link time.
> - * A lot of inline functions can cause havoc with function tracing.
>   */
> -#define inline inline __gnu_inline __inline_maybe_unused notrace
> +#define inline inline __gnu_inline __inline_maybe_unused

Yes!!!  I've been wanting to do this for many years.  This will help
live patching a lot.

Acked-by: Josh Poimboeuf <jpoimboe@kernel.org>

-- 
Josh