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charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Rspam-User: X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: 5D0BF18000C X-Stat-Signature: j3c5hyx36j3mmqqux5k5j8qjur58r1c9 X-HE-Tag: 1745901866-378594 X-HE-Meta: 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 28/04/25 11:36 pm, Zi Yan wrote: > On 28 Apr 2025, at 8:04, Dev Jain wrote: > >> Override the generic definition to use get_and_clear_full_ptes(), so that >> we do a TLBI possibly only on the "contpte-edges" of the large PTE block, > > What do you mean by “contpte-edges”? Can you provide an example? get_and_clear_full_ptes -> contpte_get_and_clear_full_ptes -> contpte_try_unfold_partial, which unfolds only the start and end contpte block. Whereas, ptep_get_and_clear -> contpte_try_unfold, which means it will unfold for every contpte block. > >> instead of doing it for every contpte block, which happens for ptep_get_and_clear(). >> >> Signed-off-by: Dev Jain >> --- >> arch/arm64/include/asm/pgtable.h | 5 +++++ >> arch/arm64/mm/mmu.c | 12 +++++++++--- >> include/linux/pgtable.h | 4 ++++ >> mm/pgtable-generic.c | 16 +++++++++++----- >> 4 files changed, 29 insertions(+), 8 deletions(-) >> >> diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h >> index 2a77f11b78d5..8872ea5f0642 100644 >> --- a/arch/arm64/include/asm/pgtable.h >> +++ b/arch/arm64/include/asm/pgtable.h >> @@ -1553,6 +1553,11 @@ extern void ptep_modify_prot_commit(struct vm_area_struct *vma, >> unsigned long addr, pte_t *ptep, >> pte_t old_pte, pte_t new_pte); >> >> +#define modify_prot_start_ptes modify_prot_start_ptes >> +extern pte_t modify_prot_start_ptes(struct vm_area_struct *vma, >> + unsigned long addr, pte_t *ptep, >> + unsigned int nr); >> + >> #ifdef CONFIG_ARM64_CONTPTE >> >> /* >> diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c >> index 8fcf59ba39db..fe60be8774f4 100644 >> --- a/arch/arm64/mm/mmu.c >> +++ b/arch/arm64/mm/mmu.c >> @@ -1523,7 +1523,8 @@ static int __init prevent_bootmem_remove_init(void) >> early_initcall(prevent_bootmem_remove_init); >> #endif >> >> -pte_t ptep_modify_prot_start(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep) >> +pte_t modify_prot_start_ptes(struct vm_area_struct *vma, unsigned long addr, >> + pte_t *ptep, unsigned int nr) > > Putting ptes at the end seems to break the naming convention. How about > ptep_modify_prot_range_start? ptes_modify_prot_start might be OK too. I was actually following the convention present in include/linux/pgtable.h, look at all the functions with _ptes suffix. > >> { >> if (alternative_has_cap_unlikely(ARM64_WORKAROUND_2645198)) { >> /* >> @@ -1532,9 +1533,14 @@ pte_t ptep_modify_prot_start(struct vm_area_struct *vma, unsigned long addr, pte >> * in cases where cpu is affected with errata #2645198. >> */ >> if (pte_user_exec(ptep_get(ptep))) >> - return ptep_clear_flush(vma, addr, ptep); >> + return clear_flush_ptes(vma, addr, ptep, nr); >> } >> - return ptep_get_and_clear(vma->vm_mm, addr, ptep); >> + return get_and_clear_full_ptes(vma->vm_mm, addr, ptep, nr, 0); >> +} >> + >> +pte_t ptep_modify_prot_start(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep) >> +{ >> + return modify_prot_start_ptes(vma, addr, ptep, 1); >> } >> >> void ptep_modify_prot_commit(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep, >> diff --git a/include/linux/pgtable.h b/include/linux/pgtable.h >> index ed287289335f..10cdb87ccecf 100644 >> --- a/include/linux/pgtable.h >> +++ b/include/linux/pgtable.h >> @@ -828,6 +828,10 @@ extern pte_t ptep_clear_flush(struct vm_area_struct *vma, >> pte_t *ptep); >> #endif >> >> +extern pte_t clear_flush_ptes(struct vm_area_struct *vma, >> + unsigned long address, >> + pte_t *ptep, unsigned int nr); >> + >> #ifndef __HAVE_ARCH_PMDP_HUGE_CLEAR_FLUSH >> extern pmd_t pmdp_huge_clear_flush(struct vm_area_struct *vma, >> unsigned long address, >> diff --git a/mm/pgtable-generic.c b/mm/pgtable-generic.c >> index 5a882f2b10f9..e238f88c3cac 100644 >> --- a/mm/pgtable-generic.c >> +++ b/mm/pgtable-generic.c >> @@ -90,17 +90,23 @@ int ptep_clear_flush_young(struct vm_area_struct *vma, >> } >> #endif >> >> -#ifndef __HAVE_ARCH_PTEP_CLEAR_FLUSH >> -pte_t ptep_clear_flush(struct vm_area_struct *vma, unsigned long address, >> - pte_t *ptep) >> +pte_t clear_flush_ptes(struct vm_area_struct *vma, unsigned long address, >> + pte_t *ptep, unsigned int nr) >> { > > Ditto. > >> struct mm_struct *mm = (vma)->vm_mm; >> pte_t pte; >> - pte = ptep_get_and_clear(mm, address, ptep); >> + pte = get_and_clear_full_ptes(mm, address, ptep, nr, 0); >> if (pte_accessible(mm, pte)) >> - flush_tlb_page(vma, address); >> + flush_tlb_range(vma, address, address + nr * PAGE_SIZE); >> return pte; >> } >> + >> +#ifndef __HAVE_ARCH_PTEP_CLEAR_FLUSH >> +pte_t ptep_clear_flush(struct vm_area_struct *vma, unsigned long address, >> + pte_t *ptep) >> +{ >> + return clear_flush_ptes(vma, address, ptep, 1); >> +} >> #endif >> >> #ifdef CONFIG_TRANSPARENT_HUGEPAGE >> -- >> 2.30.2 > > > Best Regards, > Yan, Zi