[RFC] DEPT(DEPendency Tracker) with DLM(Distributed Lock Manager)

[Byungchul Park <byungchul@sk.com>]

Hi Alexander,

We briefly talked about dept with DLM in an external channel.  However,
it'd be great to discuss what to aim and how to make it in more detail,
in this mailing list.

It's worth noting that dept doesn't track dependencies beyond different
contexts to avoid adding false dependencies by any chance, which means
though dept checks the dependency sanity *globally*, when it comes to
creating dependencies, it happens only within e.g. each single system
call context, each single irq context, each worker context, and so on,
with its unique context id assigned to each independent context.

In order for dept to work on DLM, we need a way to assign a unique
context id to each interesting context in DLM's point of view, and let
dept know the id.  Once making it done, I think dept can work on DLM
perfectly.

Thoughts or any concern?

	Byungchul