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Date:   Wed, 02 Jun 2021 21:45:58 +0200
From:   Oscar Salvador <osalvador@suse.de>
To:     David Hildenbrand <david@redhat.com>
Cc:     Andrew Morton <akpm@linux-foundation.org>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        Michal Hocko <mhocko@kernel.org>,
        Anshuman Khandual <anshuman.khandual@arm.com>,
        Vlastimil Babka <vbabka@suse.cz>,
        Pavel Tatashin <pasha.tatashin@soleen.com>, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 1/3] mm,page_alloc: Use {get,put}_online_mems() to get
 stable zone's values
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On 2021-06-02 20:37, David Hildenbrand wrote:
> Long story short, using get_online_mems() looks wrong.
> 
> Maybe the current lightweight reader/writer protection does serve a 
> purpose?

It was too nice and easy to be true I guess.
Yeah, I missed the point that blocking might be an issue here, and 
hotplug operations can take really long, so not an option.
I must have switched my brain off back there, because now it is just too 
obvious.

Then I guwmess that seqlock must stay and the only thing than can go is 
the pgdat resize lock from the hotplug code.

Meh.

-- 
Oscar Salvador
SUSE L3