Re: [PATCH 2/5] workqueue: update wq_numa_possible_cpumask

Tejun Heo
2014-12-25T20:16:26Z

On Mon, Dec 15, 2014 at 10:02:04AM +0800, Lai Jiangshan wrote:
> 1) "NUMA code" = system's NUMA memory hotplug code, AKA, keep the numa mapping stable
>
> I think this is the better idea. This idea came to my mind immediately at the time
> I received the bug report. And after some discussions, I was told that it is too HARD
> to keep the numa mapping stable across multiple physical system-board/node online/offline.

If the arch needs to change it, that's fine, I guess. What I'm saying
is that we should move this table building and maintenance to numa
code proper. It was already a bit icky to build it inside workqueue.
Trying to manage it dynamically manage it from there is too ugly.
Let's please make this mapping table a proper part of NUMA
infrastructure with proper notification callbacks.

Thanks.

--
tejun