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Date: Mon, 10 Jun 2024 13:47:18 +0200
From: Oscar Salvador <osalvador@suse.de>
To: David Hildenbrand <david@redhat.com>
Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org,
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Subject: Re: [PATCH v1 1/3] mm: pass meminit_context to __free_pages_core()
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On Mon, Jun 10, 2024 at 10:38:05AM +0200, David Hildenbrand wrote:
> On 10.06.24 06:03, Oscar Salvador wrote:
> > On Fri, Jun 07, 2024 at 11:09:36AM +0200, David Hildenbrand wrote:
> > > In preparation for further changes, let's teach __free_pages_core()
> > > about the differences of memory hotplug handling.
> > > 
> > > Move the memory hotplug specific handling from generic_online_page() to
> > > __free_pages_core(), use adjust_managed_page_count() on the memory
> > > hotplug path, and spell out why memory freed via memblock
> > > cannot currently use adjust_managed_page_count().
> > > 
> > > Signed-off-by: David Hildenbrand <david@redhat.com>
> > 
> > All looks good but I am puzzled with something.
> > 
> > > +	} else {
> > > +		/* memblock adjusts totalram_pages() ahead of time. */
> > > +		atomic_long_add(nr_pages, &page_zone(page)->managed_pages);
> > > +	}
> > 
> > You say that memblock adjusts totalram_pages ahead of time, and I guess
> > you mean in memblock_free_all()
> 
> And memblock_free_late(), which uses atomic_long_inc().

Ah yes.

 
> Right (it's suboptimal, but not really problematic so far. Hopefully Wei can
> clean it up and move it in here as well)

That would be great.

> For the time being
> 
> "/* memblock adjusts totalram_pages() manually. */"

Yes, I think that is better ;-)

Thanks!
 

-- 
Oscar Salvador
SUSE Labs