The patch titled
Subject: mm/thp: rename pmd_mknotpresent() to pmd_mknotvalid()
has been added to the -mm tree. Its filename is
mm-thp-rename-pmd_mknotpresent-as-pmd_mknotvalid.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/mm-thp-rename-pmd_mknotpresent-as-pmd_mknotvalid.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/mm-thp-rename-pmd_mknotpresent-as-pmd_mknotvalid.patch
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------------------------------------------------------
From: Anshuman Khandual <anshuman.khandual@xxxxxxx>
Subject: mm/thp: rename pmd_mknotpresent() to pmd_mknotvalid()
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_mknotvalid() 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_mknotvalid(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/
Link: http://lkml.kernel.org/r/1584680057-13753-3-git-send-email-anshuman.khandual@xxxxxxx
Signed-off-by: Anshuman Khandual <anshuman.khandual@xxxxxxx>
Suggested-by: Catalin Marinas <catalin.marinas@xxxxxxx>
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: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx>
Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Cc: Paul Mackerras <paulus@xxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
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(-)
--- a/arch/arc/include/asm/hugepage.h~mm-thp-rename-pmd_mknotpresent-as-pmd_mknotvalid
+++ a/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_mknotvalid(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))
--- a/arch/arm64/include/asm/pgtable.h~mm-thp-rename-pmd_mknotpresent-as-pmd_mknotvalid
+++ a/arch/arm64/include/asm/pgtable.h
@@ -371,7 +371,7 @@ 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_mknotvalid(pmd) (__pmd(pmd_val(pmd) & ~PMD_SECT_VALID))
#define pmd_thp_or_huge(pmd) (pmd_huge(pmd) || pmd_trans_huge(pmd))
--- a/arch/arm/include/asm/pgtable-3level.h~mm-thp-rename-pmd_mknotpresent-as-pmd_mknotvalid
+++ a/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_mknotvalid(pmd_t pmd)
{
return __pmd(pmd_val(pmd) & ~L_PMD_SECT_VALID);
}
--- a/arch/mips/include/asm/pgtable.h~mm-thp-rename-pmd_mknotpresent-as-pmd_mknotvalid
+++ a/arch/mips/include/asm/pgtable.h
@@ -631,7 +631,7 @@ static inline pmd_t pmd_modify(pmd_t pmd
return pmd;
}
-static inline pmd_t pmd_mknotpresent(pmd_t pmd)
+static inline pmd_t pmd_mknotvalid(pmd_t pmd)
{
pmd_val(pmd) &= ~(_PAGE_PRESENT | _PAGE_VALID | _PAGE_DIRTY);
--- a/arch/x86/include/asm/pgtable.h~mm-thp-rename-pmd_mknotpresent-as-pmd_mknotvalid
+++ a/arch/x86/include/asm/pgtable.h
@@ -624,7 +624,7 @@ static inline pud_t pfn_pud(unsigned lon
return __pud(pfn | check_pgprot(pgprot));
}
-static inline pmd_t pmd_mknotpresent(pmd_t pmd)
+static inline pmd_t pmd_mknotvalid(pmd_t pmd)
{
return pfn_pmd(pmd_pfn(pmd),
__pgprot(pmd_flags(pmd) & ~(_PAGE_PRESENT|_PAGE_PROTNONE)));
--- a/arch/x86/mm/kmmio.c~mm-thp-rename-pmd_mknotpresent-as-pmd_mknotvalid
+++ a/arch/x86/mm/kmmio.c
@@ -130,7 +130,7 @@ static void clear_pmd_presence(pmd_t *pm
pmdval_t v = pmd_val(*pmd);
if (clear) {
*old = v;
- new_pmd = pmd_mknotpresent(*pmd);
+ new_pmd = pmd_mknotvalid(*pmd);
} else {
/* Presume this has been called with clear==true previously */
new_pmd = __pmd(*old);
--- a/mm/pgtable-generic.c~mm-thp-rename-pmd_mknotpresent-as-pmd_mknotvalid
+++ a/mm/pgtable-generic.c
@@ -194,7 +194,7 @@ pgtable_t pgtable_trans_huge_withdraw(st
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_mknotvalid(*pmdp));
flush_pmd_tlb_range(vma, address, address + HPAGE_PMD_SIZE);
return old;
}
_
Patches currently in -mm which might be from anshuman.khandual@xxxxxxx are
mm-debug-add-tests-validating-architecture-page-table-helpers.patch
powerpc-mm-drop-platform-defined-pmd_mknotpresent.patch
mm-thp-rename-pmd_mknotpresent-as-pmd_mknotvalid.patch
