From: Anshuman Khandual <anshuman.khandual@xxxxxxx> Subject: mm/thp: rename pmd_mknotpresent() as pmd_mkinvalid() 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/ [anshuman.khandual@xxxxxxx: change pmd_mknotvalid() to pmd_mkinvalid() per Will] Link: http://lkml.kernel.org/r/1587520326-10099-3-git-send-email-anshuman.khandual@xxxxxxx 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> Acked-by: Will Deacon <will@xxxxxxxxxx> Cc: Vineet Gupta <vgupta@xxxxxxxxxxxx> Cc: Russell King <linux@xxxxxxxxxxxxxxx> Cc: Catalin Marinas <catalin.marinas@xxxxxxx> 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_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)) --- a/arch/arm64/include/asm/pgtable.h~mm-thp-rename-pmd_mknotpresent-as-pmd_mknotvalid +++ a/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)) --- 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_mkinvalid(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_mkinvalid(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_mkinvalid(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_mkinvalid(*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_mkinvalid(*pmdp)); flush_pmd_tlb_range(vma, address, address + HPAGE_PMD_SIZE); return old; } _
