[RFC]Pid conversion between pid namespace

[chenhanxiao at cn.fujitsu.com]

> -----Original Message-----
> From: Serge E. Hallyn [mailto:serge at hallyn.com]
> Sent: Thursday, August 28, 2014 9:50 PM
> To: Chen, Hanxiao/陈 晗霄
> Cc: Serge Hallyn; Richard Weinberger (richard at nod.at);
[snip]

> > > I like your proc approach.  Do you have an implementation?
> >
> > Thanks for your comments.
> > I'm preparing the pidns hierarchy patch.
> > It seems that it's not easy to carry it out.
> 
> :)  Not entirely surprised.
> 
> Please do send patches earlier rather than later to avoid going
> down a path that someone's going to nack anyway.

I've almost finished ns hierarchy patch
and do some tests now.
It will be sent in the next week.

Thanks,
- Chen