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Subject: Re: [PATCH 5/6] LoongArch: Add raw_show_trace to enable guess
 unwinder default
To:     Huacai Chen <chenhuacai@kernel.org>
Cc:     WANG Xuerui <kernel@xen0n.name>,
        Qing Zhang <zhangqing@loongson.cn>, loongarch@lists.linux.dev,
        linux-kernel@vger.kernel.org, Steven Rostedt <rostedt@goodmis.org>,
        Masami Hiramatsu <mhiramat@kernel.org>,
        Mark Rutland <mark.rutland@arm.com>
References: <20221215040141.18610-1-hejinyang@loongson.cn>
 <20221215040141.18610-6-hejinyang@loongson.cn>
 <CAAhV-H4QwWV+q_ROSbw10n3mj64BPsiAoErR7k_wZ4v0zG3nhw@mail.gmail.com>
From:   Jinyang He <hejinyang@loongson.cn>
Message-ID: <fb7740c7-1bdb-ad71-50f9-284551032568@loongson.cn>
Date:   Thu, 15 Dec 2022 14:48:27 +0800
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On 2022-12-15 14:15, Huacai Chen wrote:

> Hi, Jinyang,
>
> Is this patch really necessary?

Of course not. When I developed and tested this series, I always compile
the kernel twice, maybe more :-(, to do comparisons between the result from
guess and result from prologue to determine whether prologue is effective.
Also, the guess_unwinder might be more reliable if function_graph is
enabled, because prologue_unwinder may stop by strange code flow. If you
think it is meaningless, I'll remove it in the next version. It doesn't
affect other patches in this series.


Thanks,

Jinyang