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Message-ID: <bb71d77e-583a-d216-1aae-2bc062318888@redhat.com>
Date:   Wed, 22 Jun 2022 10:31:12 +0200
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Subject: Re: [PATCH v2 1/2] mm/page_alloc: Do not calculate node's total pages
 and memmap pages when empty
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To:     Muchun Song <songmuchun@bytedance.com>,
        Oscar Salvador <osalvador@suse.de>
Cc:     Andrew Morton <akpm@linux-foundation.org>,
        Michal Hocko <mhocko@kernel.org>, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org
References: <20220621041717.6355-1-osalvador@suse.de>
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 <506203e3-1de0-1187-5234-7afc66d4ddfe@redhat.com>
 <YrKQyhwDwMvueOUc@localhost.localdomain>
 <YrKS6aFHKRyZzAwi@FVFYT0MHHV2J.usts.net>
From:   David Hildenbrand <david@redhat.com>
Organization: Red Hat
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On 22.06.22 05:56, Muchun Song wrote:
> On Wed, Jun 22, 2022 at 05:47:22AM +0200, Oscar Salvador wrote:
>> On Tue, Jun 21, 2022 at 09:44:47AM +0200, David Hildenbrand wrote:
>>>
>>>
>>> It's worth noting that the check in pgdat_is_empty() is slightly
>>> different. I *think* it doesn't matter in practice, yet I wonder if we
>>> should simply fixup (currently unused) pgdat_is_empty().
>>
>> I guess we could change it to
>>
>>  static inline bool pgdat_is_empty(pg_data_t *pgdat)
>>  {
>> 	 return node_start_pfn(pgdat->node_id) == node_end_pfn(pgdat->node_id)
>>  }
>>
>> ? And maybe even rename it to to node_is_empty (not sure why but I tend to like
> 
> At least I like this name (node_is_empty) as well.
> 

Let's try keeping it consistent. I think node_is_empty() might indicate
that we're punching in a node id instead of a pgdat.


-- 
Thanks,

David / dhildenb