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charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: 7036514000B X-Rspam-User: X-Rspamd-Server: rspam11 X-Stat-Signature: 3eg6pn4w6p5ir6muge6ypqh8tyjp3auk X-HE-Tag: 1747817017-670205 X-HE-Meta: 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 hqbIYWgs r7GZYKyMk6/rELoW5YCkPNnK/JCH9v8t1g4sKhpMHuzm4Mh5KOtCqCn8c3DBiVfNEne/Qcp7cT47e6IKa68eaUjGM15MIKacf/a9yKTpKdio4wxqH+ONkFQxyE4bD8De1huHnP9MbyCQ0MF0IwC/JTxVWjhzPQsjYiNDQVCtrsb7pzDQqL3g5RIrCLsHSjMp+LdWI3cB1hUAJNsH85lKAiXnG34m+nkkFX8EunXMUjYG8VxR7G49awFvwqw== 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 19/05/2025 08:48, 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 LGTM; a lot less churn than before. Reviewed-by: Ryan Roberts > --- > mm/mprotect.c | 36 +++++++++++++++++++++++++++++------- > 1 file changed, 29 insertions(+), 7 deletions(-) > > diff --git a/mm/mprotect.c b/mm/mprotect.c > index 88608d0dc2c2..1ee160ed0b14 100644 > --- a/mm/mprotect.c > +++ b/mm/mprotect.c > @@ -83,6 +83,18 @@ bool can_change_pte_writable(struct vm_area_struct *vma, unsigned long addr, > return pte_dirty(pte); > } > > +static int mprotect_batch(struct folio *folio, unsigned long addr, pte_t *ptep, > + pte_t pte, int max_nr_ptes) > +{ > + const fpb_t flags = FPB_IGNORE_DIRTY | FPB_IGNORE_SOFT_DIRTY; > + > + if (!folio_test_large(folio) || (max_nr_ptes == 1)) > + return 1; > + > + return folio_pte_batch(folio, addr, ptep, pte, max_nr_ptes, flags, > + NULL, NULL, NULL); > +} > + > static long change_pte_range(struct mmu_gather *tlb, > struct vm_area_struct *vma, pmd_t *pmd, unsigned long addr, > unsigned long end, pgprot_t newprot, unsigned long cp_flags) > @@ -94,6 +106,7 @@ 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_ptes; > > tlb_change_page_size(tlb, PAGE_SIZE); > pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); > @@ -108,8 +121,10 @@ static long change_pte_range(struct mmu_gather *tlb, > flush_tlb_batched_pending(vma->vm_mm); > arch_enter_lazy_mmu_mode(); > do { > + nr_ptes = 1; > oldpte = ptep_get(pte); > if (pte_present(oldpte)) { > + int max_nr_ptes = (end - addr) >> PAGE_SHIFT; > pte_t ptent; > > /* > @@ -126,15 +141,18 @@ static long change_pte_range(struct mmu_gather *tlb, > continue; > > folio = vm_normal_folio(vma, addr, oldpte); > - if (!folio || folio_is_zone_device(folio) || > - folio_test_ksm(folio)) > + if (!folio) > continue; > > + if (folio_is_zone_device(folio) || > + folio_test_ksm(folio)) > + goto skip_batch; > + > /* Also skip shared copy-on-write pages */ > if (is_cow_mapping(vma->vm_flags) && > (folio_maybe_dma_pinned(folio) || > folio_maybe_mapped_shared(folio))) > - continue; > + goto skip_batch; > > /* > * While migration can move some dirty pages, > @@ -143,7 +161,7 @@ static long change_pte_range(struct mmu_gather *tlb, > */ > if (folio_is_file_lru(folio) && > folio_test_dirty(folio)) > - continue; > + goto skip_batch; > > /* > * Don't mess with PTEs if page is already on the node > @@ -151,7 +169,7 @@ static long change_pte_range(struct mmu_gather *tlb, > */ > nid = folio_nid(folio); > if (target_node == nid) > - continue; > + goto skip_batch; > toptier = node_is_toptier(nid); > > /* > @@ -159,8 +177,12 @@ static long change_pte_range(struct mmu_gather *tlb, > * balancing is disabled > */ > if (!(sysctl_numa_balancing_mode & NUMA_BALANCING_NORMAL) && > - toptier) > + toptier) { > +skip_batch: > + nr_ptes = mprotect_batch(folio, addr, pte, > + oldpte, max_nr_ptes); > continue; > + } > if (folio_use_access_time(folio)) > folio_xchg_access_time(folio, > jiffies_to_msecs(jiffies)); > @@ -280,7 +302,7 @@ static long change_pte_range(struct mmu_gather *tlb, > pages++; > } > } > - } while (pte++, addr += PAGE_SIZE, addr != end); > + } while (pte += nr_ptes, addr += nr_ptes * PAGE_SIZE, addr != end); > arch_leave_lazy_mmu_mode(); > pte_unmap_unlock(pte - 1, ptl); >