linux-kernel - [PATCH] mm: Refine __{pgd,p4d,pud,pmd,pte}_alloc_one

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Message-ID: <20251107095536.3101371-1-chenhuacai@loongson.cn>
Date: Fri,  7 Nov 2025 17:55:36 +0800
From: Huacai Chen <chenhuacai@...ngson.cn>
To: Huacai Chen <chenhuacai@...nel.org>,
	Andrew Morton <akpm@...ux-foundation.org>
Cc: Arnd Bergmann <arnd@...db.de>,
	Vishal Moola <vishal.moola@...il.com>,
	Kevin Brodsky <kevin.brodsky@....com>,
	Jan Kara <jack@...e.cz>,
	linux-mm@...ck.org,
	linux-arch@...r.kernel.org,
	linux-kernel@...r.kernel.org,
	Huacai Chen <chenhuacai@...ngson.cn>
Subject: [PATCH] mm: Refine __{pgd,p4d,pud,pmd,pte}_alloc_one_*() about HIGHMEM

__{pgd,p4d,pud,pmd,pte}_alloc_one_*() always allocate pages with GFP
flag GFP_PGTABLE_KERNEL/GFP_PGTABLE_USER. These two macros are defined
as follows:

There is no __GFP_HIGHMEM in them, so we needn't to clear __GFP_HIGHMEM
explicitly.

Signed-off-by: Huacai Chen <chenhuacai@...ngson.cn>
---
 include/asm-generic/pgalloc.h | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/include/asm-generic/pgalloc.h b/include/asm-generic/pgalloc.h
index 3c8ec3bfea44..706e87b43b19 100644
--- a/include/asm-generic/pgalloc.h
+++ b/include/asm-generic/pgalloc.h
@@ -18,8 +18,7 @@
  */
 static inline pte_t *__pte_alloc_one_kernel_noprof(struct mm_struct *mm)
 {
-	struct ptdesc *ptdesc = pagetable_alloc_noprof(GFP_PGTABLE_KERNEL &
-			~__GFP_HIGHMEM, 0);
+	struct ptdesc *ptdesc = pagetable_alloc_noprof(GFP_PGTABLE_KERNEL, 0);
 
 	if (!ptdesc)
 		return NULL;
@@ -172,7 +171,6 @@ static inline pud_t *__pud_alloc_one_noprof(struct mm_struct *mm, unsigned long
 
 	if (mm == &init_mm)
 		gfp = GFP_PGTABLE_KERNEL;
-	gfp &= ~__GFP_HIGHMEM;
 
 	ptdesc = pagetable_alloc_noprof(gfp, 0);
 	if (!ptdesc)
@@ -226,7 +224,6 @@ static inline p4d_t *__p4d_alloc_one_noprof(struct mm_struct *mm, unsigned long
 
 	if (mm == &init_mm)
 		gfp = GFP_PGTABLE_KERNEL;
-	gfp &= ~__GFP_HIGHMEM;
 
 	ptdesc = pagetable_alloc_noprof(gfp, 0);
 	if (!ptdesc)
@@ -270,7 +267,6 @@ static inline pgd_t *__pgd_alloc_noprof(struct mm_struct *mm, unsigned int order
 
 	if (mm == &init_mm)
 		gfp = GFP_PGTABLE_KERNEL;
-	gfp &= ~__GFP_HIGHMEM;
 
 	ptdesc = pagetable_alloc_noprof(gfp, order);
 	if (!ptdesc)
-- 
2.47.3