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Date: Wed, 26 Jun 2013 11:21:02 +0400
From: Cyrill Gorcunov <gorcunov@gmail.com>
To: Andy Lutomirski <luto@amacapital.net>
Cc: Oleg Nesterov <oleg@redhat.com>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] proc: Expose /proc/<pid>/task/<tid>/children
 unconditionally
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On Tue, Jun 25, 2013 at 03:01:35PM -0700, Andy Lutomirski wrote:
> 
> This is a little strange.  It looks like ppid (in status) shows the
> tgid, but the actual real_parent can refer to a thread (as opposed to
> a thread group leader), and task/tid/children respects that.  So the
> tree that you get by following task/tid/ children won't be quite the
> same as the tree you get by following ppid.
> 
> I wonder if the ptid should be added to status.  Is there anything
> (other than task/tid/children) that cased which thread is the parent
> of a given task?

None I know of. As to ptid -- sounds reasonable to me. Oleg?