Re: [PATCH 0/5] Make cpuid <-> nodeid mapping persistent.

Tejun Heo
2015-07-23T18:32:34Z

Hello, Tang.

On Thu, Jul 23, 2015 at 12:44:53PM +0800, Tang Chen wrote:
> Allocating cpuid when a new cpu comes up and reusing the cpuid when it
> comes up again is possible. But I'm not quite sure if it will be less
> modification
> because we still need an array or bit map or something to keep the mapping,
> and select backup nodes for cpus on memory-less nodes when allocating
> memory.
>
> I can post a set of patches for this idea. And then we can see which one is
> better.

I suspect the difference could be that in the current code the users
(workqueue) can remain the same while if we do it lazily there
probably needs to be a way to poke it. As long as the IDs are
allocated to the online CPUs first, I think pre-allocating everything
should be fine too.

Thanks.

--
tejun