linux-kernel - [PATCH] mm, hugetlb: fix "treat_as_movable" condition in htlb_alloc

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Date:   Fri, 29 Sep 2017 17:13:39 +0200
From:   Alexandru Moise <00moses.alexander00@...il.com>
To:     akpm@...ux-foundation.org
Cc:     mike.kravetz@...cle.com, mhocko@...e.com,
        n-horiguchi@...jp.nec.com, aneesh.kumar@...ux.vnet.ibm.com,
        punit.agrawal@....com, gerald.schaefer@...ibm.com,
        aarcange@...hat.com, linux-mm@...ck.org,
        linux-kernel@...r.kernel.org, kirill@...temov.name
Subject: [PATCH] mm, hugetlb: fix "treat_as_movable" condition in
 htlb_alloc_mask

If hugepage_migration_supported() returns true, this renders the
hugepages_treat_as_movable sysctl completely pointless.

Let's keep this behavior optional by switching the if() condition
from || to &&.

Signed-off-by: Alexandru Moise <00moses.alexander00@...il.com>
---
 mm/hugetlb.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 424b0ef08a60..ab28de0122af 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -926,7 +926,7 @@ static struct page *dequeue_huge_page_nodemask(struct hstate *h, gfp_t gfp_mask,
 /* Movability of hugepages depends on migration support. */
 static inline gfp_t htlb_alloc_mask(struct hstate *h)
 {
-	if (hugepages_treat_as_movable || hugepage_migration_supported(h))
+	if (hugepages_treat_as_movable && hugepage_migration_supported(h))
 		return GFP_HIGHUSER_MOVABLE;
 	else
 		return GFP_HIGHUSER;
-- 
2.14.2