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charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: 87DC680008 X-Rspam-User: X-Rspamd-Server: rspam07 X-Stat-Signature: sm9jrfyztk5o6q4p5awphwrtwub7z9my X-HE-Tag: 1745917167-458772 X-HE-Meta: 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 s4Y3L5k7 CHVUgKRmOFyTY+kvcMplKreQ4Fs2EkgNTrf0k5Fe2iNark5IjL+2VOGlaJQcAhGpj920kRixqZ5/PJNxko3ldUAEGl0CXthDuZsHJZq5EUuC/pGSjKtdwhW6VyW7aKg+tLtXunz3uk8lG1BGuIX7iKaDa+5ktUG+ryeHf4XOeu8u8TC7o+TKO7SQjQihpasYl0BRb2Nq7zWDYBaU= 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 29/04/25 12:44 pm, Anshuman Khandual wrote: > On 4/29/25 10:53, Dev Jain wrote: >> In case of prot_numa, there are various cases in which we can skip to the >> next iteration. Since the skip condition is based on the folio and not >> the PTEs, we can skip a PTE batch. >> >> Signed-off-by: Dev Jain >> --- >> mm/mprotect.c | 27 ++++++++++++++++++++------- >> 1 file changed, 20 insertions(+), 7 deletions(-) >> >> diff --git a/mm/mprotect.c b/mm/mprotect.c >> index 70f59aa8c2a8..ec5d17af7650 100644 >> --- a/mm/mprotect.c >> +++ b/mm/mprotect.c >> @@ -91,6 +91,9 @@ static bool prot_numa_skip(struct vm_area_struct *vma, struct folio *folio, >> bool toptier; >> int nid; >> >> + if (folio_is_zone_device(folio) || folio_test_ksm(folio)) >> + return true; >> + > > Moving these here from prot_numa_avoid_fault() could have been done > earlier, while adding prot_numa_skip() itself in the previous patch > (in case this helper is determined to be really required). True. I'll do that. > >> /* Also skip shared copy-on-write pages */ >> if (is_cow_mapping(vma->vm_flags) && >> (folio_maybe_dma_pinned(folio) || >> @@ -126,8 +129,10 @@ static bool prot_numa_skip(struct vm_area_struct *vma, struct folio *folio, >> } >> >> static bool prot_numa_avoid_fault(struct vm_area_struct *vma, >> - unsigned long addr, pte_t oldpte, int target_node) >> + unsigned long addr, pte_t *pte, pte_t oldpte, int target_node, >> + int max_nr, int *nr) >> { >> + const fpb_t flags = FPB_IGNORE_DIRTY | FPB_IGNORE_SOFT_DIRTY; > > Flags are all correct. > >> struct folio *folio; >> int ret; >> >> @@ -136,12 +141,16 @@ static bool prot_numa_avoid_fault(struct vm_area_struct *vma, >> return true; >> >> folio = vm_normal_folio(vma, addr, oldpte); >> - if (!folio || folio_is_zone_device(folio) || >> - folio_test_ksm(folio)) >> + if (!folio) >> return true; >> + >> ret = prot_numa_skip(vma, folio, target_node); >> - if (ret) >> + if (ret) { >> + if (folio_test_large(folio) && max_nr != 1) > > Conditional checks are all correct. > >> + *nr = folio_pte_batch(folio, addr, pte, oldpte, >> + max_nr, flags, NULL, NULL, NULL); >> return ret; >> + } >> if (folio_use_access_time(folio)) >> folio_xchg_access_time(folio, >> jiffies_to_msecs(jiffies)); >> @@ -159,6 +168,7 @@ static long change_pte_range(struct mmu_gather *tlb, >> bool prot_numa = cp_flags & MM_CP_PROT_NUMA; >> bool uffd_wp = cp_flags & MM_CP_UFFD_WP; >> bool uffd_wp_resolve = cp_flags & MM_CP_UFFD_WP_RESOLVE; >> + int nr; >> >> tlb_change_page_size(tlb, PAGE_SIZE); >> pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); >> @@ -173,8 +183,10 @@ static long change_pte_range(struct mmu_gather *tlb, >> flush_tlb_batched_pending(vma->vm_mm); >> arch_enter_lazy_mmu_mode(); >> do { >> + nr = 1; > > 'nr' resets each iteration. > >> oldpte = ptep_get(pte); >> if (pte_present(oldpte)) { >> + int max_nr = (end - addr) >> PAGE_SHIFT; > > Small nit - 'max_nr' declaration could be moved earlier along with 'nr'. Sure. > >> pte_t ptent; >> >> /* >> @@ -182,8 +194,9 @@ static long change_pte_range(struct mmu_gather *tlb, >> * pages. See similar comment in change_huge_pmd. >> */ >> if (prot_numa && >> - prot_numa_avoid_fault(vma, addr, >> - oldpte, target_node)) >> + prot_numa_avoid_fault(vma, addr, pte, >> + oldpte, target_node, >> + max_nr, &nr)) >> continue; >> >> oldpte = ptep_modify_prot_start(vma, addr, pte); >> @@ -300,7 +313,7 @@ static long change_pte_range(struct mmu_gather *tlb, >> pages++; >> } >> } >> - } while (pte++, addr += PAGE_SIZE, addr != end); >> + } while (pte += nr, addr += nr * PAGE_SIZE, addr != end); >> arch_leave_lazy_mmu_mode(); >> pte_unmap_unlock(pte - 1, ptl); >> > > Otherwise LGTM