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charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: 3EFD1160002 X-Rspam-User: X-Rspamd-Server: rspam07 X-Stat-Signature: rf3ocua5pxe4g18ct85kjf8htmit73fr X-HE-Tag: 1745910882-56658 X-HE-Meta: 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 gsjW8dQ2 HLHIpEUWnkG6YvTq697OpMyErKLHxk+OK0vMpy+T8ZdqySYpyZyStI9+YAi+Db2A46pZgGr/OgUoa4jcurUXaM3wyPkSteAQs+D7LsQpo9LwrwpyGE9j317VGwfDmlP4zamw2qIgAWAlDq0z/CQxAX2mz3gXWTi8OkCb2NZkueEMRTCMQPf1NaxmLpXWbbRBHKIa53siiMRphIvH6YIOb9KQSw98iw7QMO7w9CgQN3zYPSesa12FHHzYf4A== 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 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). > /* 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'. > 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