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Date:   Fri, 6 Jan 2023 17:51:55 +0800
From:   Chen Yu <yu.c.chen@intel.com>
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CC:     <mingo@redhat.com>, <peterz@infradead.org>,
        <juri.lelli@redhat.com>, <vincent.guittot@linaro.org>,
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Subject: Re: [PATCH] sched: print parent comm in sched_show_task()
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Hi Tio,
On 2023-01-04 at 01:51:30 +0800, 张元瀚 wrote:
> Hi Chen,
> Thanks for your advice!
> 
> > Maybe struct task_struct *parent = rcu_dereference(p->real_parent);
> > and use parent directly to get its pid and comm?
> 
> Yes! It is good to write this way.
> 
> > Maybe off-topic, what if the parent is a kernel thread/worker? It might
> have extra
> > name information such as kthread->full_name or worker->desc according to
> proc_task_name().
> 
> I'm not quite sure if it is necessary to fetch that extra information since
> our sched_show_task() prints p->comm ourselves.
> But, assuming we get the parent's name in the same way we get
> proc_task_name(), there are some new issues I'd like to discuss.
> For example, if we write like this:
Petr suggested to keep it simple in another thread, so I think we do not
need to let extra information involve in for now.

thanks,
Chenyu