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From: John Ogness <john.ogness@linutronix.de>
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To: Song Chen <chensong_2000@189.cn>, Andrew Halaney <ahalaney@redhat.com>
Cc: Derek Barbosa <debarbos@redhat.com>, pmladek@suse.com,
 rostedt@goodmis.org, senozhatsky@chromium.org,
 linux-rt-users@vger.kernel.org, linux-kernel@vger.kernel.org,
 williams@redhat.com, jlelli@redhat.com
Subject: Re: a question about how to debug this case in ftrace
In-Reply-To: <e6b0ba9e-e8f6-4c42-9f63-e3b67d7edbf0@189.cn>
References: <ZnGlt4uQRP_4nWu4@debarbos-thinkpadt14sgen2i.remote.csb>
 <6802e81c-1926-4195-812a-1a5fe13bcdde@189.cn>
 <xiune2bsqgin5ksk33q5bkihuz5qrv5casjofdyopes55zfcpc@uvvnlwxb4wcp>
 <4d198032-d4e1-4a84-8f56-1b31157e9323@189.cn>
 <e6b0ba9e-e8f6-4c42-9f63-e3b67d7edbf0@189.cn>
Date: Wed, 26 Jun 2024 09:31:03 +0206
Message-ID: <8734p0jhdc.fsf@jogness.linutronix.de>
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On 2024-06-26, Song Chen <chensong_2000@189.cn> wrote:
> ohh, by the way, i'm curious why softlockup/hardlockup/hungtask don't
> have ftrace dump as well as rcu stall, or is it possible to add a
> parameter in cmdline to redirect
> softlockup/hardlockup/hungtask/rcustall warning either to ftrace or
> printk.

Are you aware of the printk:console ftrace event? If you enable it, all
printk output also goes into the ftrace buffers.

John Ogness