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Date:   Thu, 18 Aug 2022 17:05:43 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Alexei Starovoitov <alexei.starovoitov@gmail.com>
Cc:     Jiri Olsa <olsajiri@gmail.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Alexei Starovoitov <ast@kernel.org>,
        Daniel Borkmann <daniel@iogearbox.net>,
        Andrii Nakryiko <andrii@kernel.org>,
        Ingo Molnar <mingo@redhat.com>, bpf <bpf@vger.kernel.org>,
        Martin KaFai Lau <kafai@fb.com>,
        Song Liu <songliubraving@fb.com>, Yonghong Song <yhs@fb.com>,
        John Fastabend <john.fastabend@gmail.com>,
        KP Singh <kpsingh@chromium.org>,
        Stanislav Fomichev <sdf@google.com>,
        Hao Luo <haoluo@google.com>,
        LKML <linux-kernel@vger.kernel.org>,
        Josh Poimboeuf <jpoimboe@redhat.com>
Subject: Re: [RFC] ftrace: Add support to keep some functions out of ftrace
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On Thu, 18 Aug 2022 14:00:21 -0700
Alexei Starovoitov <alexei.starovoitov@gmail.com> wrote:

> > #ifdef CONFIG_X86
> > # define NON_MCOUNT_PATCHABLE KEEP(*(__patchable_function_entries))
> > # define MCOUNT_PATCHABLE
> > #else
> > # define NON_MCOUNT_PATCHABLE
> > # define MCOUNT_PATCHABLE  KEEP(*(__patchable_function_entries))
> > #endif
> >
> >   #define MCOUNT_REC()    . = ALIGN(8);     \
> >     __start_mcount_loc = .;                 \
> >     KEEP(*(__mcount_loc))                   \
> >     MCOUNT_PATCHABLE                        \
> >     __stop_mcount_loc = .;                  \
> >     NON_MCOUNT_PATCHABLE                    \
> >    ...
> >
> > ??  
> 
> That's what more or less Peter's patch is doing:

Heh.

> Here it is again for reference:
> https://git.kernel.org/pub/scm/linux/kernel/git/peterz/queue.git/commit/?id=8d075bdf11193f1d276bf19fa56b4b8dfe24df9e

Thanks, I missed seeing this.

-- Steve