Re: [PATCH v2 5/5] mm/page_alloc: Only call pgdat_set_deferred_range when the system boots

[Michal Hocko]

On Thu 19-07-18 15:58:59, Oscar Salvador wrote:
> On Thu, Jul 19, 2018 at 03:46:22PM +0200, Michal Hocko wrote:
> > On Thu 19-07-18 15:27:40, osalvador@xxxxxxxxxxxxxxxxxx wrote:
> > > From: Oscar Salvador <osalvador@xxxxxxx>
> > > 
> > > We should only care about deferred initialization when booting.
> > 
> > Again why is this worth doing?
> 
> Well, it is not a big win if that is what you meant.
> 
> Those two fields are only being used when dealing with deferred pages,
> which only happens at boot time.
> 
> If later on, free_area_init_node gets called from memhotplug code,
> we will also set the fields, although they will not be used.
> 
> Is this a problem? No, but I think it is more clear from the code if we
> see when this is called.
> So I would say it was only for code consistency.

Then put it to the changelog.

> If you think this this is not worth, I am ok with dropping it.

I am not really sure. I am not a big fan of SYSTEM_BOOTING global
thingy so I would rather not spread its usage.
-- 
Michal Hocko
SUSE Labs