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charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspam-User: X-Rspamd-Queue-Id: 297368001A X-Rspamd-Server: rspam04 X-Stat-Signature: 3fg7hwq6g38tc6ub9nfrkbc7emkxenim X-HE-Tag: 1765986226-232616 X-HE-Meta: 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 qftEi2P/ wqwkJ8nRHT6Ug/y1YX1RfzefgdpxtWmmpjv7//DAm/E9TiveJCmgZULUFwyKHksl72Sa6tYKbUMRoueGLJRm0+CtmAW+vjhipqDUSt0ww4fxKGUoBbmTkJ1PMdphSRMDvE0diJGotfO08VLyPjkBo1+ESFah8lWsee2hmNEMDMmlrSCQ= 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: Sorry I'm a bit late to the party... On 11/12/2025 08:16, 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. > > 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 | 44 ++++++++++++++++++++++---------- > 2 files changed, 37 insertions(+), 19 deletions(-) > > diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h > index 0944e296dd4a..e03034683156 100644 > --- a/arch/arm64/include/asm/pgtable.h > +++ b/arch/arm64/include/asm/pgtable.h > @@ -1679,10 +1679,10 @@ 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); > +extern int contpte_test_and_clear_young_ptes(struct vm_area_struct *vma, > + unsigned long addr, pte_t *ptep, unsigned int nr); > +extern int contpte_clear_flush_young_ptes(struct vm_area_struct *vma, > + unsigned long addr, pte_t *ptep, unsigned int nr); The "contpte_" functions are intended to be private to the arm64 arch and should be exposed via the generic APIs. But I don't see any generic batched API for this, so you're only actually able to pass CONT_PTES as nr. Perhaps you're planning to define "test_and_clear_young_ptes()" and "clear_flush_young_ptes()" in later patches? > 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, > @@ -1854,7 +1854,7 @@ 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); > } > > #define __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH > @@ -1866,7 +1866,7 @@ 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); > } > > #define wrprotect_ptes wrprotect_ptes > diff --git a/arch/arm64/mm/contpte.c b/arch/arm64/mm/contpte.c > index c0557945939c..19b122441be3 100644 > --- a/arch/arm64/mm/contpte.c > +++ b/arch/arm64/mm/contpte.c > @@ -488,8 +488,9 @@ 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 > @@ -500,39 +501,56 @@ int contpte_ptep_test_and_clear_young(struct vm_area_struct *vma, > * having to unfold. > */ > > + unsigned long start = addr; Personally I wouldn't bother defining start - just reuse addr. You're incrementing start in the below loop, so it's more appropriate to call it addr anyway. > + unsigned long end = start + nr * PAGE_SIZE; > int young = 0; > int i; > > - ptep = contpte_align_down(ptep); > - addr = ALIGN_DOWN(addr, CONT_PTE_SIZE); > + if (pte_cont(__ptep_get(ptep + nr - 1))) > + end = ALIGN(end, CONT_PTE_SIZE); > > - for (i = 0; i < CONT_PTES; i++, ptep++, addr += PAGE_SIZE) > - young |= __ptep_test_and_clear_young(vma, addr, ptep); > + if (pte_cont(__ptep_get(ptep))) { > + start = ALIGN_DOWN(start, CONT_PTE_SIZE); > + ptep = contpte_align_down(ptep); > + } > + > + nr = (end - start) / PAGE_SIZE; > + for (i = 0; i < nr; i++, ptep++, start += PAGE_SIZE) Given you're now defining end, perhaps we don't need nr? for (; addr != end; ptep++, addr += PAGE_SIZE) young |= __ptep_test_and_clear_young(vma, addr, ptep); > + young |= __ptep_test_and_clear_young(vma, start, 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 start = addr; > + unsigned long end = start + nr * PAGE_SIZE; > + > + if (pte_cont(__ptep_get(ptep + nr - 1))) > + end = ALIGN(end, CONT_PTE_SIZE); > + > + if (pte_cont(__ptep_get(ptep))) > + start = ALIGN_DOWN(start, CONT_PTE_SIZE); > + We now have this pattern of expanding contpte blocks up and down in 3 places. Perhaps create a helper? Thanks, Ryan > /* > * 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, start, end, > PAGE_SIZE, true, 3); > } > > 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)