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Date:   Mon, 3 May 2021 09:50:30 -0400 (EDT)
From:   Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
To:     rostedt <rostedt@goodmis.org>
Cc:     peter enderborg <Peter.Enderborg@sony.com>,
        "Eric W. Biederman" <ebiederm@xmission.com>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        Ingo Molnar <mingo@redhat.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Alexei Starovoitov <ast@kernel.org>,
        Christian Brauner <christian.brauner@ubuntu.com>,
        Davidlohr Bueso <dave@stgolabs.net>,
        Michel Lespinasse <walken@google.com>,
        Jann Horn <jannh@google.com>,
        christophe leroy <christophe.leroy@c-s.fr>,
        Minchan Kim <minchan@kernel.org>
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Subject: Re: [PATCH 1/2] tracing: Add a trace for task_exit
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----- On May 1, 2021, at 9:11 AM, rostedt rostedt@goodmis.org wrote:

> On Sat, 1 May 2021 09:29:41 +0000
> <Peter.Enderborg@sony.com> wrote:
> 
>> On 4/30/21 7:48 PM, Eric W. Biederman wrote:
>> > Peter Enderborg <peter.enderborg@sony.com> writes:
>> >  
>> >> This is the peer functions to task_rename and task_newtask.
>> >> With this we get hole "life-cycle" of task and can easily
>> >> see short livied task and their exit status.
>> > This patch is incorrect.  The location you are dealing with is not part
>> > of task exit.  The location you have instrumented is part of reaping a
>> > task which can come arbitrarily long after the task exits.
>> 
>> That is what it aiming. When using this as tool for userspace you
>> would like to know when the task is done. When it no longer
>> holds any thing that might have any impact. If you think the
>> exit imply something more specific I can change the name.
>> 
>> I thought exit was a good name, it is in in exit.c.
>> 
>> Will the name task_done, task_finished or task_reaped work for you?
> 
> I think "task_reaped" is probably the best name, and the most
> descriptive of what happened.

What would it provide that is not already available through the "sched_process_free"
tracepoint in delayed_put_task_struct ?

Thanks,

Mathieu

-- 
Mathieu Desnoyers
EfficiOS Inc.
http://www.efficios.com