Re: [PATCH 1/1] mm/memory_hotplug: Adds option to hot-add memory in ZONE_MOVABLE

From: Michal Hocko
Date: Thu Jul 18 2019 - 11:57:09 EST

On Thu 18-07-19 12:50:29, Leonardo Bras wrote:
> On Thu, 2019-07-18 at 08:12 +0200, Oscar Salvador wrote:
> > We do already have "movable_node" boot option, which exactly has that
> > effect.
> > Any hotplugged range will be placed in ZONE_MOVABLE.
> Oh, I was not aware of it.
> > Why do we need yet another option to achieve the same? Was not that
> > enough for your case?
> Well, another use of this config could be doing this boot option a
> default on any given kernel.
> But in the above case I agree it would be wiser to add the code on
> movable_node_is_enabled() directly, and not where I did put.
> What do you think about it?

No further config options please. We do have means a more flexible way
to achieve movable node onlining so let's use it. Or could you be more
specific about cases which cannot use the command line option and really
need a config option to workaround that?
Michal Hocko