linux-kernel - [PATCH v10 3/7] mm,hugetlb: Drop clearing of flag from prep_new_huge

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Message-Id: <20210419075413.1064-4-osalvador@suse.de>
Date:   Mon, 19 Apr 2021 09:54:09 +0200
From:   Oscar Salvador <osalvador@...e.de>
To:     Andrew Morton <akpm@...ux-foundation.org>
Cc:     Mike Kravetz <mike.kravetz@...cle.com>,
        Vlastimil Babka <vbabka@...e.cz>,
        David Hildenbrand <david@...hat.com>,
        Michal Hocko <mhocko@...nel.org>,
        Muchun Song <songmuchun@...edance.com>, linux-mm@...ck.org,
        linux-kernel@...r.kernel.org, Oscar Salvador <osalvador@...e.de>
Subject: [PATCH v10 3/7] mm,hugetlb: Drop clearing of flag from prep_new_huge_page

Pages allocated via the page allocator or CMA get its private field cleared
by means of post_alloc_hook().
Pages allocated during boot, that is directly from the memblock allocator,
get cleared by paging_init()->..->memmap_init_zone->..->__init_single_page()
before any memblock allocation.

Based on this ground, let us remove the clearing of the flag from
prep_new_huge_page() as it is not needed.
This was a leftover from 6c0371490140 ("hugetlb: convert PageHugeFreed
to HPageFreed flag"). Previously the explicit clearing was necessary
because compound allocations do not get this initialization
(see prep_compound_page).

Signed-off-by: Oscar Salvador <osalvador@...e.de>
Acked-by: Michal Hocko <mhocko@...e.com>
Reviewed-by: David Hildenbrand <david@...hat.com>
Reviewed-by: Mike Kravetz <mike.kravetz@...cle.com>
---
 mm/hugetlb.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 54d81d5947ed..2cb9fa79cbaa 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -1493,7 +1493,6 @@ static void prep_new_huge_page(struct hstate *h, struct page *page, int nid)
 	spin_lock_irq(&hugetlb_lock);
 	h->nr_huge_pages++;
 	h->nr_huge_pages_node[nid]++;
-	ClearHPageFreed(page);
 	spin_unlock_irq(&hugetlb_lock);
 }

-- 
2.16.3