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Date:   Sun, 18 Sep 2022 11:07:12 -0300
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Subject: Re: [PATCH V3 07/11] notifiers: Add tracepoints to the notifiers
 infrastructure
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To:     akpm@linux-foundation.org, Xiaoming Ni <nixiaoming@huawei.com>,
        Arjan van de Ven <arjan@linux.intel.com>
Cc:     kexec@lists.infradead.org, bhe@redhat.com, pmladek@suse.com,
        linux-kernel@vger.kernel.org, linux-hyperv@vger.kernel.org,
        netdev@vger.kernel.org, x86@kernel.org, kernel-dev@igalia.com,
        kernel@gpiccoli.net, halves@canonical.com, fabiomirmar@gmail.com,
        alejandro.j.jimenez@oracle.com, andriy.shevchenko@linux.intel.com,
        arnd@arndb.de, bp@alien8.de, corbet@lwn.net,
        d.hatayama@jp.fujitsu.com, dave.hansen@linux.intel.com,
        dyoung@redhat.com, feng.tang@intel.com, gregkh@linuxfoundation.org,
        mikelley@microsoft.com, hidehiro.kawai.ez@hitachi.com,
        jgross@suse.com, john.ogness@linutronix.de, keescook@chromium.org,
        luto@kernel.org, mhiramat@kernel.org, mingo@redhat.com,
        paulmck@kernel.org, peterz@infradead.org, rostedt@goodmis.org,
        senozhatsky@chromium.org, stern@rowland.harvard.edu,
        tglx@linutronix.de, vgoyal@redhat.com, vkuznets@redhat.com,
        will@kernel.org, xuqiang36@huawei.com,
        Cong Wang <xiyou.wangcong@gmail.com>,
        Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
        Valentin Schneider <valentin.schneider@arm.com>
References: <20220819221731.480795-1-gpiccoli@igalia.com>
 <20220819221731.480795-8-gpiccoli@igalia.com>
From:   "Guilherme G. Piccoli" <gpiccoli@igalia.com>
In-Reply-To: <20220819221731.480795-8-gpiccoli@igalia.com>
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On 19/08/2022 19:17, Guilherme G. Piccoli wrote:
> Currently there is no way to show the callback names for registered,
> unregistered or executed notifiers. This is very useful for debug
> purposes, hence add this functionality here in the form of notifiers'
> tracepoints, one per operation.
> 
> Cc: Arjan van de Ven <arjan@linux.intel.com>
> Cc: Cong Wang <xiyou.wangcong@gmail.com>
> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
> Cc: Steven Rostedt <rostedt@goodmis.org>
> Cc: Valentin Schneider <valentin.schneider@arm.com>
> Cc: Xiaoming Ni <nixiaoming@huawei.com>
> Signed-off-by: Guilherme G. Piccoli <gpiccoli@igalia.com>
> 
> ---
> 
> V3:
> - Yet another major change - thanks to Arjan's great suggestion,
> refactored the code to make use of tracepoints instead of guarding
> the output with a Kconfig debug setting.
> 
> V2:
> - Major improvement thanks to the great idea from Xiaoming - changed
> all the ksym wheel reinvention to printk %ps modifier;
> 
> - Instead of ifdefs, using IS_ENABLED() - thanks Steven.
> 
> - Removed an unlikely() hint on debug path.
> 
> [...]

Hi Arjan / Xioming, apologies for the ping.
Do you think the patch is good enough now? I liked the tracepoint
approach, indeed it was a much better idea than guarding the prints with
the DEBUG Kconfig heheh

Appreciate your opinions!
Thanks in advance,


Guilherme