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charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspam-User: X-Rspamd-Queue-Id: 3D14640006 X-Rspamd-Server: rspam04 X-Stat-Signature: 4gji43cehptw7a381taon1bfpaib46hj X-HE-Tag: 1766585260-193737 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 23/12/2025 05:48, Baolin Wang wrote: > Currently, contpte_ptep_test_and_clear_young() and contpte_ptep_clear_flush_young() > only clear the young flag and flush TLBs for PTEs within the contiguous range. > To support batch PTE operations for other sized large folios in the following > patches, adding a new parameter to specify the number of PTEs that map consecutive > pages of the same large folio in a single VMA and a single page table. > > While we are at it, rename the functions to maintain consistency with other > contpte_*() functions. > > Signed-off-by: Baolin Wang > --- > arch/arm64/include/asm/pgtable.h | 12 ++++++------ > arch/arm64/mm/contpte.c | 33 ++++++++++++++++++-------------- > 2 files changed, 25 insertions(+), 20 deletions(-) > > diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h > index 445e18e92221..d5fbe72e820a 100644 > --- a/arch/arm64/include/asm/pgtable.h > +++ b/arch/arm64/include/asm/pgtable.h > @@ -1648,10 +1648,10 @@ extern void contpte_clear_full_ptes(struct mm_struct *mm, unsigned long addr, > extern pte_t contpte_get_and_clear_full_ptes(struct mm_struct *mm, > unsigned long addr, pte_t *ptep, > unsigned int nr, int full); > -extern int contpte_ptep_test_and_clear_young(struct vm_area_struct *vma, > - unsigned long addr, pte_t *ptep); > -extern int contpte_ptep_clear_flush_young(struct vm_area_struct *vma, > - unsigned long addr, pte_t *ptep); > +int contpte_test_and_clear_young_ptes(struct vm_area_struct *vma, > + unsigned long addr, pte_t *ptep, unsigned int nr); > +int contpte_clear_flush_young_ptes(struct vm_area_struct *vma, > + unsigned long addr, pte_t *ptep, unsigned int nr); > extern void contpte_wrprotect_ptes(struct mm_struct *mm, unsigned long addr, > pte_t *ptep, unsigned int nr); > extern int contpte_ptep_set_access_flags(struct vm_area_struct *vma, > @@ -1823,7 +1823,7 @@ static inline int ptep_test_and_clear_young(struct vm_area_struct *vma, > if (likely(!pte_valid_cont(orig_pte))) > return __ptep_test_and_clear_young(vma, addr, ptep); > > - return contpte_ptep_test_and_clear_young(vma, addr, ptep); > + return contpte_test_and_clear_young_ptes(vma, addr, ptep, CONT_PTES); As per your fixup patch, I agree that nr should be 1 here, not CONT_PTES. > } > > #define __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH > @@ -1835,7 +1835,7 @@ static inline int ptep_clear_flush_young(struct vm_area_struct *vma, > if (likely(!pte_valid_cont(orig_pte))) > return __ptep_clear_flush_young(vma, addr, ptep); > > - return contpte_ptep_clear_flush_young(vma, addr, ptep); > + return contpte_clear_flush_young_ptes(vma, addr, ptep, CONT_PTES); And same here. > } > > #define wrprotect_ptes wrprotect_ptes > diff --git a/arch/arm64/mm/contpte.c b/arch/arm64/mm/contpte.c > index e4ddeb46f25d..b929a455103f 100644 > --- a/arch/arm64/mm/contpte.c > +++ b/arch/arm64/mm/contpte.c > @@ -508,8 +508,9 @@ pte_t contpte_get_and_clear_full_ptes(struct mm_struct *mm, > } > EXPORT_SYMBOL_GPL(contpte_get_and_clear_full_ptes); > > -int contpte_ptep_test_and_clear_young(struct vm_area_struct *vma, > - unsigned long addr, pte_t *ptep) > +int contpte_test_and_clear_young_ptes(struct vm_area_struct *vma, > + unsigned long addr, pte_t *ptep, > + unsigned int nr) > { > /* > * ptep_clear_flush_young() technically requires us to clear the access > @@ -518,41 +519,45 @@ int contpte_ptep_test_and_clear_young(struct vm_area_struct *vma, > * contig range when the range is covered by a single folio, we can get > * away with clearing young for the whole contig range here, so we avoid > * having to unfold. > + * > + * The 'nr' means consecutive (present) PTEs that map consecutive pages > + * of the same large folio in a single VMA and a single page table. > */ > > + unsigned long end = addr + nr * PAGE_SIZE; > int young = 0; > - int i; > > - ptep = contpte_align_down(ptep); > - addr = ALIGN_DOWN(addr, CONT_PTE_SIZE); > - > - for (i = 0; i < CONT_PTES; i++, ptep++, addr += PAGE_SIZE) > + ptep = contpte_align_addr_ptep(&addr, &end, ptep, nr); > + for (; addr != end; ptep++, addr += PAGE_SIZE) > young |= __ptep_test_and_clear_young(vma, addr, ptep); > > return young; > } > -EXPORT_SYMBOL_GPL(contpte_ptep_test_and_clear_young); > +EXPORT_SYMBOL_GPL(contpte_test_and_clear_young_ptes); > > -int contpte_ptep_clear_flush_young(struct vm_area_struct *vma, > - unsigned long addr, pte_t *ptep) > +int contpte_clear_flush_young_ptes(struct vm_area_struct *vma, > + unsigned long addr, pte_t *ptep, > + unsigned int nr) > { > int young; > > - young = contpte_ptep_test_and_clear_young(vma, addr, ptep); > + young = contpte_test_and_clear_young_ptes(vma, addr, ptep, nr); > > if (young) { > + unsigned long end = addr + nr * PAGE_SIZE; > + > + contpte_align_addr_ptep(&addr, &end, ptep, nr); > /* > * See comment in __ptep_clear_flush_young(); same rationale for > * eliding the trailing DSB applies here. > */ > - addr = ALIGN_DOWN(addr, CONT_PTE_SIZE); > - __flush_tlb_range_nosync(vma->vm_mm, addr, addr + CONT_PTE_SIZE, > + __flush_tlb_range_nosync(vma->vm_mm, addr, end, > PAGE_SIZE, true, 3); Hmm... The requirement is that we must flush the _page_ if clearing access for a pte that does not have the contiguous bit set, or we must flush the _contpte block_ if clearing access for a pte that does have the contiguous bit set. With your changes, you may call for a large range that covers multiple contpte blocks but only has a single pte in a single contpte block for which the access bit was previously set. But that will cause flushing the TLB for the full range. Could this cause a performance issue? Yes, no, maybe... I think it's unlikely but I wouldn't rule it out in some edge case. I wonder if it's better to track the sub-ranges where access was cleared and only issue tlbi for those sub-ranges? Probably just keep it simple (the way you have done it) until/unless we see an actual problem? Thanks, Ryan > } > > return young; > } > -EXPORT_SYMBOL_GPL(contpte_ptep_clear_flush_young); > +EXPORT_SYMBOL_GPL(contpte_clear_flush_young_ptes); > > void contpte_wrprotect_ptes(struct mm_struct *mm, unsigned long addr, > pte_t *ptep, unsigned int nr)