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Date:   Fri, 15 Jul 2022 09:51:56 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Marco Elver <elver@google.com>
Cc:     Petr Mladek <pmladek@suse.com>,
        "Paul E . McKenney" <paulmck@kernel.org>,
        John Ogness <john.ogness@linutronix.de>,
        Sergey Senozhatsky <senozhatsky@chromium.org>,
        kasan-dev@googlegroups.com, Thomas Gleixner <tglx@linutronix.de>,
        Johannes Berg <johannes.berg@intel.com>,
        Alexander Potapenko <glider@google.com>,
        Dmitry Vyukov <dvyukov@google.com>,
        Naresh Kamboju <naresh.kamboju@linaro.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Linux Kernel Functional Testing <lkft@linaro.org>,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] printk: Make console tracepoint safe in NMI() context
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On Fri, 15 Jul 2022 14:39:52 +0200
Marco Elver <elver@google.com> wrote:

> Couldn't this just use rcu_is_watching()?
> 
>   | * rcu_is_watching - see if RCU thinks that the current CPU is not idle

Maybe, but I was thinking that Petr had a way to hit the issue that we
worry about. But since the non _rcuide() call requires rcu watching,
prehaps that is better to use.

-- Steve