From: Zi Yan <ziy@xxxxxxxxxx> do_numa_page() and do_huge_pmd_numa_page() share a lot of common code. To reduce redundancy, move common code to numa_migrate_prep() and rename the function to numa_migrate_check() to reflect its functionality. There is some code difference between do_numa_page() and do_huge_pmd_numa_page() before the code move: 1. do_huge_pmd_numa_page() did not check shared folios to set TNF_SHARED. 2. do_huge_pmd_numa_page() did not check and skip zone device folios. Signed-off-by: Zi Yan <ziy@xxxxxxxxxx> --- mm/huge_memory.c | 28 ++++++----------- mm/internal.h | 5 +-- mm/memory.c | 81 +++++++++++++++++++++++------------------------- 3 files changed, 52 insertions(+), 62 deletions(-) diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 8c11d6da4b36..66d67d13e0dc 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -1670,10 +1670,10 @@ vm_fault_t do_huge_pmd_numa_page(struct vm_fault *vmf) pmd_t pmd; struct folio *folio; unsigned long haddr = vmf->address & HPAGE_PMD_MASK; - int nid = NUMA_NO_NODE; - int target_nid, last_cpupid = (-1 & LAST_CPUPID_MASK); + int target_nid = NUMA_NO_NODE; + int last_cpupid = (-1 & LAST_CPUPID_MASK); bool writable = false; - int flags = 0; + int flags = 0, nr_pages; vmf->ptl = pmd_lock(vma->vm_mm, vmf->pmd); if (unlikely(!pmd_same(oldpmd, *vmf->pmd))) { @@ -1693,21 +1693,13 @@ vm_fault_t do_huge_pmd_numa_page(struct vm_fault *vmf) writable = true; folio = vm_normal_folio_pmd(vma, haddr, pmd); - if (!folio) + if (!folio || folio_is_zone_device(folio)) goto out_map; - /* See similar comment in do_numa_page for explanation */ - if (!writable) - flags |= TNF_NO_GROUP; + nr_pages = folio_nr_pages(folio); - nid = folio_nid(folio); - /* - * For memory tiering mode, cpupid of slow memory page is used - * to record page access time. So use default value. - */ - if (folio_has_cpupid(folio)) - last_cpupid = folio_last_cpupid(folio); - target_nid = numa_migrate_prep(folio, vmf, haddr, nid, &flags); + target_nid = numa_migrate_check(folio, vmf, haddr, writable, + &flags, &last_cpupid); if (target_nid == NUMA_NO_NODE) goto out_map; if (migrate_misplaced_folio_prepare(folio, vma, target_nid)) { @@ -1720,8 +1712,8 @@ vm_fault_t do_huge_pmd_numa_page(struct vm_fault *vmf) if (!migrate_misplaced_folio(folio, vma, target_nid)) { flags |= TNF_MIGRATED; - nid = target_nid; } else { + target_nid = NUMA_NO_NODE; flags |= TNF_MIGRATE_FAIL; vmf->ptl = pmd_lock(vma->vm_mm, vmf->pmd); if (unlikely(!pmd_same(oldpmd, *vmf->pmd))) { @@ -1732,8 +1724,8 @@ vm_fault_t do_huge_pmd_numa_page(struct vm_fault *vmf) } out: - if (nid != NUMA_NO_NODE) - task_numa_fault(last_cpupid, nid, HPAGE_PMD_NR, flags); + if (target_nid != NUMA_NO_NODE) + task_numa_fault(last_cpupid, target_nid, nr_pages, flags); return 0; diff --git a/mm/internal.h b/mm/internal.h index b4d86436565b..7782b7bb3383 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -1217,8 +1217,9 @@ void vunmap_range_noflush(unsigned long start, unsigned long end); void __vunmap_range_noflush(unsigned long start, unsigned long end); -int numa_migrate_prep(struct folio *folio, struct vm_fault *vmf, - unsigned long addr, int page_nid, int *flags); +int numa_migrate_check(struct folio *folio, struct vm_fault *vmf, + unsigned long addr, bool writable, + int *flags, int *last_cpupid); void free_zone_device_folio(struct folio *folio); int migrate_device_coherent_page(struct page *page); diff --git a/mm/memory.c b/mm/memory.c index 96c2f5b3d796..a252c0f13755 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -5209,16 +5209,42 @@ static vm_fault_t do_fault(struct vm_fault *vmf) return ret; } -int numa_migrate_prep(struct folio *folio, struct vm_fault *vmf, - unsigned long addr, int page_nid, int *flags) +int numa_migrate_check(struct folio *folio, struct vm_fault *vmf, + unsigned long addr, bool writable, + int *flags, int *last_cpupid) { struct vm_area_struct *vma = vmf->vma; + /* + * Avoid grouping on RO pages in general. RO pages shouldn't hurt as + * much anyway since they can be in shared cache state. This misses + * the case where a mapping is writable but the process never writes + * to it but pte_write gets cleared during protection updates and + * pte_dirty has unpredictable behaviour between PTE scan updates, + * background writeback, dirty balancing and application behaviour. + */ + if (!writable) + *flags |= TNF_NO_GROUP; + + /* + * Flag if the folio is shared between multiple address spaces. This + * is later used when determining whether to group tasks together + */ + if (folio_likely_mapped_shared(folio) && (vma->vm_flags & VM_SHARED)) + *flags |= TNF_SHARED; + + /* + * For memory tiering mode, cpupid of slow memory page is used + * to record page access time. + */ + if (folio_has_cpupid(folio)) + *last_cpupid = folio_last_cpupid(folio); + /* Record the current PID acceesing VMA */ vma_set_access_pid_bit(vma); count_vm_numa_event(NUMA_HINT_FAULTS); - if (page_nid == numa_node_id()) { + if (folio_nid(folio) == numa_node_id()) { count_vm_numa_event(NUMA_HINT_FAULTS_LOCAL); *flags |= TNF_FAULT_LOCAL; } @@ -5284,12 +5310,11 @@ static vm_fault_t do_numa_page(struct vm_fault *vmf) { struct vm_area_struct *vma = vmf->vma; struct folio *folio = NULL; - int nid = NUMA_NO_NODE; + int target_nid = NUMA_NO_NODE; bool writable = false, ignore_writable = false; bool pte_write_upgrade = vma_wants_manual_pte_write_upgrade(vma); - int last_cpupid; - int target_nid; - pte_t pte, old_pte; + int last_cpupid = (-1 & LAST_CPUPID_MASK); + pte_t pte, old_pte = vmf->orig_pte; int flags = 0, nr_pages; /* @@ -5297,10 +5322,7 @@ static vm_fault_t do_numa_page(struct vm_fault *vmf) * table lock, that its contents have not changed during fault handling. */ spin_lock(vmf->ptl); - /* Read the live PTE from the page tables: */ - old_pte = ptep_get(vmf->pte); - - if (unlikely(!pte_same(old_pte, vmf->orig_pte))) { + if (unlikely(!pte_same(old_pte, *vmf->pte))) { pte_unmap_unlock(vmf->pte, vmf->ptl); goto out; } @@ -5320,35 +5342,10 @@ static vm_fault_t do_numa_page(struct vm_fault *vmf) if (!folio || folio_is_zone_device(folio)) goto out_map; - /* - * Avoid grouping on RO pages in general. RO pages shouldn't hurt as - * much anyway since they can be in shared cache state. This misses - * the case where a mapping is writable but the process never writes - * to it but pte_write gets cleared during protection updates and - * pte_dirty has unpredictable behaviour between PTE scan updates, - * background writeback, dirty balancing and application behaviour. - */ - if (!writable) - flags |= TNF_NO_GROUP; - - /* - * Flag if the folio is shared between multiple address spaces. This - * is later used when determining whether to group tasks together - */ - if (folio_likely_mapped_shared(folio) && (vma->vm_flags & VM_SHARED)) - flags |= TNF_SHARED; - - nid = folio_nid(folio); nr_pages = folio_nr_pages(folio); - /* - * For memory tiering mode, cpupid of slow memory page is used - * to record page access time. So use default value. - */ - if (!folio_has_cpupid(folio)) - last_cpupid = (-1 & LAST_CPUPID_MASK); - else - last_cpupid = folio_last_cpupid(folio); - target_nid = numa_migrate_prep(folio, vmf, vmf->address, nid, &flags); + + target_nid = numa_migrate_check(folio, vmf, vmf->address, writable, + &flags, &last_cpupid); if (target_nid == NUMA_NO_NODE) goto out_map; if (migrate_misplaced_folio_prepare(folio, vma, target_nid)) { @@ -5362,9 +5359,9 @@ static vm_fault_t do_numa_page(struct vm_fault *vmf) /* Migrate to the requested node */ if (!migrate_misplaced_folio(folio, vma, target_nid)) { - nid = target_nid; flags |= TNF_MIGRATED; } else { + target_nid = NUMA_NO_NODE; flags |= TNF_MIGRATE_FAIL; vmf->pte = pte_offset_map_lock(vma->vm_mm, vmf->pmd, vmf->address, &vmf->ptl); @@ -5378,8 +5375,8 @@ static vm_fault_t do_numa_page(struct vm_fault *vmf) } out: - if (nid != NUMA_NO_NODE) - task_numa_fault(last_cpupid, nid, nr_pages, flags); + if (target_nid != NUMA_NO_NODE) + task_numa_fault(last_cpupid, target_nid, nr_pages, flags); return 0; out_map: /* -- 2.43.0