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Date:   Thu, 20 Oct 2022 10:15:49 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Song Chen <chensong_2000@189.cn>
Cc:     mingo@redhat.com, mhiramat@kernel.org,
        linux-kernel@vger.kernel.org, xiehuan09@gmail.com
Subject: Re: [PATCH] trace/ring_buffer: remove unused arguments
Message-ID: <20221020101549.06e3fa5b@gandalf.local.home>
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On Thu, 20 Oct 2022 22:06:51 +0800
Song Chen <chensong_2000@189.cn> wrote:

> As a argument, event has nothing to do with either
> ring_buffer_unlock_commit or rb_commit and cleaning
> it up has no side effect.

OK, so this is because of a389d86f7fd0 ("ring-buffer: Have nested events
still record running time stamp") which removed the usage of event in rb_commit():

 static void rb_commit(struct ring_buffer_per_cpu *cpu_buffer,
                      struct ring_buffer_event *event)
 {
        local_inc(&cpu_buffer->entries);
-       rb_update_write_stamp(cpu_buffer, event);
        rb_end_commit(cpu_buffer);
 }


I guess this doesn't hurt.

-- Steve

> 
> Signed-off-by: Song Chen <chensong_2000@189.cn>
> ---
>  include/linux/ring_buffer.h          |  3 +--
>  kernel/trace/ring_buffer.c           | 12 +++++-------
>  kernel/trace/ring_buffer_benchmark.c |  2 +-
>  kernel/trace/trace.c                 |  2 +-
>  4 files changed, 8 insertions(+), 11 deletions(-)