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Date:   Wed, 22 Jun 2022 11:56:25 +0800
From:   Muchun Song <songmuchun@bytedance.com>
To:     Oscar Salvador <osalvador@suse.de>
Cc:     David Hildenbrand <david@redhat.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Michal Hocko <mhocko@kernel.org>, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org
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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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.

Thanks.

> that more than pgdat) 
> 
> I could squeeze a "fixup" patch for that before this one. 
> 
> > 
> > Anyhow
> > 
> > Reviewed-by: David Hildenbrand <david@redhat.com>
> 
> Thanks!
> 
> 
> -- 
> Oscar Salvador
> SUSE Labs
>