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Message-ID: <6c6fc4fa-6464-2dbf-40da-e3c61f322d95@redhat.com>
Date:   Thu, 17 Feb 2022 18:49:00 +0100
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Subject: Re: [RFC V2 17/21] watchdog/dev: Add tracepoints
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To:     Guenter Roeck <linux@roeck-us.net>,
        Daniel Bristot de Oliveira <bristot@kernel.org>,
        "Peter.Enderborg@sony.com" <Peter.Enderborg@sony.com>,
        Wim Van Sebroeck <wim@linux-watchdog.org>
Cc:     Jonathan Corbet <corbet@lwn.net>, Ingo Molnar <mingo@redhat.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Peter Zijlstra <peterz@infradead.org>,
        Will Deacon <will@kernel.org>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Marco Elver <elver@google.com>,
        Dmitry Vyukov <dvyukov@google.com>,
        "Paul E. McKenney" <paulmck@kernel.org>,
        Shuah Khan <skhan@linuxfoundation.org>,
        Juri Lelli <juri.lelli@redhat.com>,
        Clark Williams <williams@redhat.com>,
        "linux-doc@vger.kernel.org" <linux-doc@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "linux-trace-devel@vger.kernel.org" 
        <linux-trace-devel@vger.kernel.org>,
        Steven Rostedt <rostedt@goodmis.org>
References: <cover.1644830251.git.bristot@kernel.org>
 <e67874c8b676ea8dfe38679efa25363889bb1e76.1644830251.git.bristot@kernel.org>
 <96f418b4-0ba8-01fe-ead0-2028bfc42560@sony.com>
 <ba924008-c0ab-4800-aac4-d9d9ae930c32@kernel.org>
 <ef1b1d99-6172-2b4d-9612-7ecbe8fc6c8b@roeck-us.net>
From:   Gabriele Paoloni <gpaoloni@redhat.com>
In-Reply-To: <ef1b1d99-6172-2b4d-9612-7ecbe8fc6c8b@roeck-us.net>
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On 17/02/2022 18:27, Guenter Roeck wrote:
> On 2/17/22 08:27, Daniel Bristot de Oliveira wrote:
>> Hi Peter
>>
>> On 2/16/22 17:01, Peter.Enderborg@sony.com wrote:
>>> On 2/14/22 11:45, Daniel Bristot de Oliveira wrote:
>>>> Add a set of tracepoints, enabling the observability of the watchdog
>>>> device interactions with user-space.
>>>>
>>>> The events are:
>>>>     watchdog:watchdog_open
>>>>     watchdog:watchdog_close
>>>>     watchdog:watchdog_start
>>>>     watchdog:watchdog_stop
>>>>     watchdog:watchdog_set_timeout
>>>>     watchdog:watchdog_ping
>>>>     watchdog:watchdog_nowayout
>>>>     watchdog:watchdog_set_keep_alive
>>>>     watchdog:watchdog_keep_alive
>>>
>>> Some watchdogs have a bark functionality, I think it should be event
>>> for that too.
>>>
>>
>> I understand. The problems is that I do not see the bark abstraction
>> in the
>> watchdog_dev layer.
>>
> 
> I don't even know what "bark functionality" means. A new term for
> pretimeout ?
> Something else ?

From my understanding the bark timeout is actually the pretimeout
whereas the bite timeout is the actual timeout.
I think in the Kernel ftwdt010_wdt and qcom-wdt are bark/bite WTDs

Gab


> 
> Guenter
> 
>> In the case I am investigating (the safety_monitor/safety_app) the
>> bark is
>> outside of the "OS" view, it is an hardware action - like. shutdown.
>>
>> Am I missing something? Thoughts?
>>
>> -- Daniel
>