[CRIU] [RFC PATCH] proc, pidns: Add highpid

[Florian Weimer]

* Andy Lutomirski:

> The initial implementation is straightforward: highpid is simply a
> 64-bit counter. If a high-end system can fork every 3 ns (which
> would be amazing, given that just allocating a pid requires at
> atomic operation), it would take well over 1000 years for highpid to
> wrap.

I'm not sure if I'm reading the patch correctly, but is the counter
namespaced?  If yes, why?