[PATCH V2 2/2] mm/thp: Rename pmd_mknotpresent() as pmd_mkinvalid()
From: Anshuman Khandual
Date: Tue Apr 21 2020 - 21:52:44 EST
pmd_present() is expected to test positive after pmdp_mknotpresent() as the
PMD entry still points to a valid huge page in memory. pmdp_mknotpresent()
implies that given PMD entry is just invalidated from MMU perspective while
still holding on to pmd_page() referred valid huge page thus also clearing
pmd_present() test. This creates the following situation which is counter
intuitive.
[pmd_present(pmd_mknotpresent(pmd)) = true]
This renames pmd_mknotpresent() as pmd_mkinvalid() reflecting the helper's
functionality more accurately while changing the above mentioned situation
as follows. This does not create any functional change.
[pmd_present(pmd_mkinvalid(pmd)) = true]
This is not applicable for platforms that define own pmdp_invalidate() via
__HAVE_ARCH_PMDP_INVALIDATE. Suggestion for renaming came during a previous
discussion here.
https://patchwork.kernel.org/patch/11019637/
Cc: Vineet Gupta <vgupta@xxxxxxxxxxxx>
Cc: Russell King <linux@xxxxxxxxxxxxxxx>
Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
Cc: Will Deacon <will@xxxxxxxxxx>
Cc: Thomas Bogendoerfer <tsbogend@xxxxxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: "H. Peter Anvin" <hpa@xxxxxxxxx>
Cc: Steven Rostedt <rostedt@xxxxxxxxxxx>
Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Cc: Andy Lutomirski <luto@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: nouveau@xxxxxxxxxxxxxxxxxxxxx
Cc: linux-snps-arc@xxxxxxxxxxxxxxxxxxx
Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
Cc: linux-mips@xxxxxxxxxxxxxxx
Cc: x86@xxxxxxxxxx
Cc: linux-mm@xxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
Suggested-by: Catalin Marinas <catalin.marinas@xxxxxxx>
Acked-by: Will Deacon <will@xxxxxxxxxx>
Signed-off-by: Anshuman Khandual <anshuman.khandual@xxxxxxx>
---
arch/arc/include/asm/hugepage.h | 2 +-
arch/arm/include/asm/pgtable-3level.h | 2 +-
arch/arm64/include/asm/pgtable.h | 2 +-
arch/mips/include/asm/pgtable.h | 2 +-
arch/x86/include/asm/pgtable.h | 2 +-
arch/x86/mm/kmmio.c | 2 +-
mm/pgtable-generic.c | 2 +-
7 files changed, 7 insertions(+), 7 deletions(-)
diff --git a/arch/arc/include/asm/hugepage.h b/arch/arc/include/asm/hugepage.h
index 30ac40fed2c5..4eef17c5c1da 100644
--- a/arch/arc/include/asm/hugepage.h
+++ b/arch/arc/include/asm/hugepage.h
@@ -26,7 +26,7 @@ static inline pmd_t pte_pmd(pte_t pte)
#define pmd_mkold(pmd) pte_pmd(pte_mkold(pmd_pte(pmd)))
#define pmd_mkyoung(pmd) pte_pmd(pte_mkyoung(pmd_pte(pmd)))
#define pmd_mkhuge(pmd) pte_pmd(pte_mkhuge(pmd_pte(pmd)))
-#define pmd_mknotpresent(pmd) pte_pmd(pte_mknotpresent(pmd_pte(pmd)))
+#define pmd_mkinvalid(pmd) pte_pmd(pte_mknotpresent(pmd_pte(pmd)))
#define pmd_mkclean(pmd) pte_pmd(pte_mkclean(pmd_pte(pmd)))
#define pmd_write(pmd) pte_write(pmd_pte(pmd))
diff --git a/arch/arm/include/asm/pgtable-3level.h b/arch/arm/include/asm/pgtable-3level.h
index 36805f94939e..1933aed9f68d 100644
--- a/arch/arm/include/asm/pgtable-3level.h
+++ b/arch/arm/include/asm/pgtable-3level.h
@@ -221,7 +221,7 @@ PMD_BIT_FUNC(mkyoung, |= PMD_SECT_AF);
#define pmdp_establish generic_pmdp_establish
/* represent a notpresent pmd by faulting entry, this is used by pmdp_invalidate */
-static inline pmd_t pmd_mknotpresent(pmd_t pmd)
+static inline pmd_t pmd_mkinvalid(pmd_t pmd)
{
return __pmd(pmd_val(pmd) & ~L_PMD_SECT_VALID);
}
diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
index 538c85e62f86..9a68bbce26d0 100644
--- a/arch/arm64/include/asm/pgtable.h
+++ b/arch/arm64/include/asm/pgtable.h
@@ -366,7 +366,7 @@ static inline int pmd_protnone(pmd_t pmd)
#define pmd_mkclean(pmd) pte_pmd(pte_mkclean(pmd_pte(pmd)))
#define pmd_mkdirty(pmd) pte_pmd(pte_mkdirty(pmd_pte(pmd)))
#define pmd_mkyoung(pmd) pte_pmd(pte_mkyoung(pmd_pte(pmd)))
-#define pmd_mknotpresent(pmd) (__pmd(pmd_val(pmd) & ~PMD_SECT_VALID))
+#define pmd_mkinvalid(pmd) (__pmd(pmd_val(pmd) & ~PMD_SECT_VALID))
#define pmd_thp_or_huge(pmd) (pmd_huge(pmd) || pmd_trans_huge(pmd))
diff --git a/arch/mips/include/asm/pgtable.h b/arch/mips/include/asm/pgtable.h
index f1801e7a4b15..bfbab6652e20 100644
--- a/arch/mips/include/asm/pgtable.h
+++ b/arch/mips/include/asm/pgtable.h
@@ -631,7 +631,7 @@ static inline pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot)
return pmd;
}
-static inline pmd_t pmd_mknotpresent(pmd_t pmd)
+static inline pmd_t pmd_mkinvalid(pmd_t pmd)
{
pmd_val(pmd) &= ~(_PAGE_PRESENT | _PAGE_VALID | _PAGE_DIRTY);
diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h
index 4d02e64af1b3..f51d8997ed00 100644
--- a/arch/x86/include/asm/pgtable.h
+++ b/arch/x86/include/asm/pgtable.h
@@ -624,7 +624,7 @@ static inline pud_t pfn_pud(unsigned long page_nr, pgprot_t pgprot)
return __pud(pfn | check_pgprot(pgprot));
}
-static inline pmd_t pmd_mknotpresent(pmd_t pmd)
+static inline pmd_t pmd_mkinvalid(pmd_t pmd)
{
return pfn_pmd(pmd_pfn(pmd),
__pgprot(pmd_flags(pmd) & ~(_PAGE_PRESENT|_PAGE_PROTNONE)));
diff --git a/arch/x86/mm/kmmio.c b/arch/x86/mm/kmmio.c
index 9994353fb75d..22bae5828c3d 100644
--- a/arch/x86/mm/kmmio.c
+++ b/arch/x86/mm/kmmio.c
@@ -130,7 +130,7 @@ static void clear_pmd_presence(pmd_t *pmd, bool clear, pmdval_t *old)
pmdval_t v = pmd_val(*pmd);
if (clear) {
*old = v;
- new_pmd = pmd_mknotpresent(*pmd);
+ new_pmd = pmd_mkinvalid(*pmd);
} else {
/* Presume this has been called with clear==true previously */
new_pmd = __pmd(*old);
diff --git a/mm/pgtable-generic.c b/mm/pgtable-generic.c
index 3d7c01e76efc..d18f0e1b6792 100644
--- a/mm/pgtable-generic.c
+++ b/mm/pgtable-generic.c
@@ -194,7 +194,7 @@ pgtable_t pgtable_trans_huge_withdraw(struct mm_struct *mm, pmd_t *pmdp)
pmd_t pmdp_invalidate(struct vm_area_struct *vma, unsigned long address,
pmd_t *pmdp)
{
- pmd_t old = pmdp_establish(vma, address, pmdp, pmd_mknotpresent(*pmdp));
+ pmd_t old = pmdp_establish(vma, address, pmdp, pmd_mkinvalid(*pmdp));
flush_pmd_tlb_range(vma, address, address + HPAGE_PMD_SIZE);
return old;
}
--
2.20.1