linux-kernel - [PATCH 06/45] mm/pagewalk: Do not try to split non-thp pud or pmd leafs

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Message-ID: <20240704043132.28501-7-osalvador@suse.de>
Date: Thu,  4 Jul 2024 06:30:53 +0200
From: Oscar Salvador <osalvador@...e.de>
To: Andrew Morton <akpm@...ux-foundation.org>
Cc: linux-kernel@...r.kernel.org,
	linux-mm@...ck.org,
	Peter Xu <peterx@...hat.com>,
	Muchun Song <muchun.song@...ux.dev>,
	David Hildenbrand <david@...hat.com>,
	SeongJae Park <sj@...nel.org>,
	Miaohe Lin <linmiaohe@...wei.com>,
	Michal Hocko <mhocko@...e.com>,
	Matthew Wilcox <willy@...radead.org>,
	Christophe Leroy <christophe.leroy@...roup.eu>,
	Oscar Salvador <osalvador@...e.de>
Subject: [PATCH 06/45] mm/pagewalk: Do not try to split non-thp pud or pmd leafs

Hugetlb pages will be handled in the generic path, so do not try to split
pud or pmd leafs if they are not thp.

Signed-off-by: Oscar Salvador <osalvador@...e.de>
---
 mm/pagewalk.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/mm/pagewalk.c b/mm/pagewalk.c
index a9c36f9e9820..78d45f1450aa 100644
--- a/mm/pagewalk.c
+++ b/mm/pagewalk.c
@@ -119,7 +119,8 @@ static int walk_pmd_range(pud_t *pud, unsigned long addr, unsigned long end,
 		 * Check this here so we only break down trans_huge
 		 * pages when we _need_ to
 		 */
-		if ((!walk->vma && (pmd_leaf(*pmd) || !pmd_present(*pmd))) ||
+		if (((!walk->vma || is_vm_hugetlb_page(walk->vma)) &&
+		    (pmd_leaf(*pmd) || !pmd_present(*pmd))) ||
 		    walk->action == ACTION_CONTINUE ||
 		    !(ops->pte_entry))
 			continue;
@@ -169,7 +170,8 @@ static int walk_pud_range(p4d_t *p4d, unsigned long addr, unsigned long end,
 		if (walk->action == ACTION_AGAIN)
 			goto again;
 
-		if ((!walk->vma && (pud_leaf(*pud) || !pud_present(*pud))) ||
+		if (((!walk->vma || is_vm_hugetlb_page(walk->vma)) &&
+		    (pud_leaf(*pud) || !pud_present(*pud))) ||
 		    walk->action == ACTION_CONTINUE ||
 		    !(ops->pmd_entry || ops->pte_entry))
 			continue;
-- 
2.26.2