Re: [RFC PATCH] x86, numa: always initialize all possible nodes

From: Mike Rapoport
Date: Fri Jan 25 2019 - 14:25:17 EST


On Fri, Jan 25, 2019 at 11:40:23AM +0100, Michal Hocko wrote:
> On Thu 24-01-19 19:51:44, Mike Rapoport wrote:
> > On Thu, Jan 24, 2019 at 03:17:27PM +0100, Michal Hocko wrote:
> > > a friendly ping for this. Does anybody see any problem with this
> > > approach?
> >
> > FWIW, it looks fine to me.
> >
> > It'd just be nice to have a few more words in the changelog about *how* the
> > x86 init was reworked ;-)
>
> Heh, I thought it was there but nope... It probably just existed in my
> head. Sorry about that. What about the following paragraphs added?
> "
> The new code relies on the arch specific initialization to allocate all
> possible NUMA nodes (including memory less) - numa_register_memblks in
> this case. Generic code then initializes both zonelists (__build_all_zonelists)
> and allocator internals (free_area_init_nodes) for all non-null pgdats
> rather than online ones.
>
> For the x86 specific part also do not make new node online in alloc_node_data
> because this is too early to know that. numa_register_memblks knows that
> a node has some memory so it can make the node online appropriately.
> init_memory_less_node hack can be safely removed altogether now.
> "

LGTM, thanks!

> --
> Michal Hocko
> SUSE Labs
>

--
Sincerely yours,
Mike.