linux-kernel - [PATCH v2] mm/hugetlb: remove redundant check in preparing and destroying gigantic page

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Date:   Tue,  2 Feb 2021 19:20:02 +0800
From:   yanfei.xu@...driver.com
To:     mike.kravetz@...cle.com, akpm@...ux-foundation.org
Cc:     linux-mm@...ck.org, linux-kernel@...r.kernel.org
Subject: [PATCH v2] mm/hugetlb: remove redundant check in preparing and destroying gigantic page

From: Yanfei Xu <yanfei.xu@...driver.com>

Gigantic page is a compound page and its order is more than 1.
Thus it must be available for hpage_pincount. Let's remove the
redundant check for gigantic page.

Signed-off-by: Yanfei Xu <yanfei.xu@...driver.com>
---
 mm/hugetlb.c | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index a3e4fa2c5e94..dac5db569ccb 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -1219,8 +1219,7 @@ static void destroy_compound_gigantic_page(struct page *page,
 	struct page *p = page + 1;
 
 	atomic_set(compound_mapcount_ptr(page), 0);
-	if (hpage_pincount_available(page))
-		atomic_set(compound_pincount_ptr(page), 0);
+	atomic_set(compound_pincount_ptr(page), 0);
 
 	for (i = 1; i < nr_pages; i++, p = mem_map_next(p, page, i)) {
 		clear_compound_head(p);
@@ -1501,9 +1500,7 @@ static void prep_compound_gigantic_page(struct page *page, unsigned int order)
 		set_compound_head(p, page);
 	}
 	atomic_set(compound_mapcount_ptr(page), -1);
-
-	if (hpage_pincount_available(page))
-		atomic_set(compound_pincount_ptr(page), 0);
+	atomic_set(compound_pincount_ptr(page), 0);
 }
 
 /*
-- 
2.27.0