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Date: Mon, 10 Jun 2024 06:03:38 +0200
From: Oscar Salvador <osalvador@suse.de>
To: David Hildenbrand <david@redhat.com>
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Subject: Re: [PATCH v1 1/3] mm: pass meminit_context to __free_pages_core()
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References: <20240607090939.89524-1-david@redhat.com>
 <20240607090939.89524-2-david@redhat.com>
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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()

 pages = free_low_memory_core_early()
 totalram_pages_add(pages);

but that is not ahead, it looks like it is upading __after__ sending
them to buddy?


-- 
Oscar Salvador
SUSE Labs