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Date:   Tue, 18 Oct 2022 09:59:32 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Song Chen <chensong_2000@189.cn>
Cc:     mingo@redhat.com, linux-kernel@vger.kernel.org,
        xiehuan09@gmail.com, Masami Hiramatsu <mhiramat@kernel.org>
Subject: Re: [PATCH] trace/kprobe: remove duplicated call of
 ring_buffer_event_data
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[ Added Masami who's the new co-maintainer, and this is his code ]

On Tue, 18 Oct 2022 15:13:06 +0800
Song Chen <chensong_2000@189.cn> wrote:

> Function __kprobe_trace_func calls ring_buffer_event_data to get
> a ring buffer, however, it has been done in above call
> trace_event_buffer_reserve.
> 
> So remove one of them.
> 

May as well add:

Fixes: 5e6cd84e2f8bd ("tracing/kprobes: Do not open code event reserve logic")

Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>

-- Steve


> Signed-off-by: Song Chen <chensong_2000@189.cn>
> ---
>  kernel/trace/trace_kprobe.c | 1 -
>  1 file changed, 1 deletion(-)
> 
> diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
> index 23f7f0ec4f4c..dfd5809a4a65 100644
> --- a/kernel/trace/trace_kprobe.c
> +++ b/kernel/trace/trace_kprobe.c
> @@ -1394,7 +1394,6 @@ __kprobe_trace_func(struct trace_kprobe *tk, struct pt_regs *regs,
>  		return;
>  
>  	fbuffer.regs = regs;
> -	entry = fbuffer.entry = ring_buffer_event_data(fbuffer.event);
>  	entry->ip = (unsigned long)tk->rp.kp.addr;
>  	store_trace_args(&entry[1], &tk->tp, regs, sizeof(*entry), dsize);
>