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Date:   Fri, 15 Jul 2022 11:02:48 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Petr Mladek <pmladek@suse.com>
Cc:     "Paul E . McKenney" <paulmck@kernel.org>,
        John Ogness <john.ogness@linutronix.de>,
        Sergey Senozhatsky <senozhatsky@chromium.org>,
        Marco Elver <elver@google.com>, 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
Message-ID: <20220715110248.02b294b7@gandalf.local.home>
In-Reply-To: <20220715120152.17760-1-pmladek@suse.com>
References: <20220715120152.17760-1-pmladek@suse.com>
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On Fri, 15 Jul 2022 14:01:52 +0200
Petr Mladek <pmladek@suse.com> wrote:

> +	/*
> +	 * trace_console_rcuidle() is not working in NMI. printk()
> +	 * is used more often in NMI than in rcuidle context.
> +	 * Choose the less evil solution here.
> +	 *
> +	 * raw_smp_processor_id() is reliable in rcuidle context.
> +	 */
> +	TP_CONDITION(!rcu_is_idle_cpu(raw_smp_processor_id())),
> +

As Marco mentioned in the other thread, would a check for
'rcu_is_watching()' be better?

-- Steve


>  	TP_STRUCT__entry(
>  		__dynamic_array(char, msg, len + 1)
>  	),