From 869f7ee6f6477341f859c8b0949ae81caf9ca7f3 Mon Sep 17 00:00:00 2001 From: "Matthew Wilcox (Oracle)" Date: Tue, 15 Feb 2022 09:28:49 -0500 Subject: [PATCH] mm/rmap: Convert try_to_unmap() to take a folio Change all three callers and the worker function try_to_unmap_one(). Signed-off-by: Matthew Wilcox (Oracle) --- include/linux/rmap.h | 4 +-- mm/huge_memory.c | 3 +- mm/khugepaged.c | 3 +- mm/memory-failure.c | 7 +++-- mm/memory_hotplug.c | 13 ++++---- mm/rmap.c | 83 +++++++++++++++++++++++++++------------------------- mm/vmscan.c | 2 +- 7 files changed, 62 insertions(+), 53 deletions(-) diff --git a/include/linux/rmap.h b/include/linux/rmap.h index 69a1664216de..a0c5c38c733f 100644 --- a/include/linux/rmap.h +++ b/include/linux/rmap.h @@ -194,7 +194,7 @@ int folio_referenced(struct folio *, int is_locked, struct mem_cgroup *memcg, unsigned long *vm_flags); void try_to_migrate(struct page *page, enum ttu_flags flags); -void try_to_unmap(struct page *, enum ttu_flags flags); +void try_to_unmap(struct folio *, enum ttu_flags flags); int make_device_exclusive_range(struct mm_struct *mm, unsigned long start, unsigned long end, struct page **pages, @@ -309,7 +309,7 @@ static inline int folio_referenced(struct folio *folio, int is_locked, return 0; } -static inline void try_to_unmap(struct page *page, enum ttu_flags flags) +static inline void try_to_unmap(struct folio *folio, enum ttu_flags flags) { } diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 583b735a079b..de684427f79c 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -2251,6 +2251,7 @@ void vma_adjust_trans_huge(struct vm_area_struct *vma, static void unmap_page(struct page *page) { + struct folio *folio = page_folio(page); enum ttu_flags ttu_flags = TTU_RMAP_LOCKED | TTU_SPLIT_HUGE_PMD | TTU_SYNC; @@ -2264,7 +2265,7 @@ static void unmap_page(struct page *page) if (PageAnon(page)) try_to_migrate(page, ttu_flags); else - try_to_unmap(page, ttu_flags | TTU_IGNORE_MLOCK); + try_to_unmap(folio, ttu_flags | TTU_IGNORE_MLOCK); VM_WARN_ON_ONCE_PAGE(page_mapped(page), page); } diff --git a/mm/khugepaged.c b/mm/khugepaged.c index fa05e6d39783..1cdf7c38b9e5 100644 --- a/mm/khugepaged.c +++ b/mm/khugepaged.c @@ -1834,7 +1834,8 @@ static void collapse_file(struct mm_struct *mm, } if (page_mapped(page)) - try_to_unmap(page, TTU_IGNORE_MLOCK | TTU_BATCH_FLUSH); + try_to_unmap(page_folio(page), + TTU_IGNORE_MLOCK | TTU_BATCH_FLUSH); xas_lock_irq(&xas); xas_set(&xas, index); diff --git a/mm/memory-failure.c b/mm/memory-failure.c index 0b72a936b8dd..258913d5e036 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -1347,6 +1347,7 @@ static int get_hwpoison_page(struct page *p, unsigned long flags) static bool hwpoison_user_mappings(struct page *p, unsigned long pfn, int flags, struct page *hpage) { + struct folio *folio = page_folio(hpage); enum ttu_flags ttu = TTU_IGNORE_MLOCK | TTU_SYNC; struct address_space *mapping; LIST_HEAD(tokill); @@ -1412,7 +1413,7 @@ static bool hwpoison_user_mappings(struct page *p, unsigned long pfn, collect_procs(hpage, &tokill, flags & MF_ACTION_REQUIRED); if (!PageHuge(hpage)) { - try_to_unmap(hpage, ttu); + try_to_unmap(folio, ttu); } else { if (!PageAnon(hpage)) { /* @@ -1424,12 +1425,12 @@ static bool hwpoison_user_mappings(struct page *p, unsigned long pfn, */ mapping = hugetlb_page_mapping_lock_write(hpage); if (mapping) { - try_to_unmap(hpage, ttu|TTU_RMAP_LOCKED); + try_to_unmap(folio, ttu|TTU_RMAP_LOCKED); i_mmap_unlock_write(mapping); } else pr_info("Memory failure: %#lx: could not lock mapping for mapped huge page\n", pfn); } else { - try_to_unmap(hpage, ttu); + try_to_unmap(folio, ttu); } } diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index 2a9627dc784c..914057da53c7 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -1690,10 +1690,13 @@ do_migrate_range(unsigned long start_pfn, unsigned long end_pfn) DEFAULT_RATELIMIT_BURST); for (pfn = start_pfn; pfn < end_pfn; pfn++) { + struct folio *folio; + if (!pfn_valid(pfn)) continue; page = pfn_to_page(pfn); - head = compound_head(page); + folio = page_folio(page); + head = &folio->page; if (PageHuge(page)) { pfn = page_to_pfn(head) + compound_nr(head) - 1; @@ -1710,10 +1713,10 @@ do_migrate_range(unsigned long start_pfn, unsigned long end_pfn) * the unmap as the catch all safety net). */ if (PageHWPoison(page)) { - if (WARN_ON(PageLRU(page))) - isolate_lru_page(page); - if (page_mapped(page)) - try_to_unmap(page, TTU_IGNORE_MLOCK); + if (WARN_ON(folio_test_lru(folio))) + folio_isolate_lru(folio); + if (folio_mapped(folio)) + try_to_unmap(folio, TTU_IGNORE_MLOCK); continue; } diff --git a/mm/rmap.c b/mm/rmap.c index 8b3d44e56e30..cf6e3de9d2f7 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -1412,7 +1412,7 @@ static bool try_to_unmap_one(struct page *page, struct vm_area_struct *vma, { struct folio *folio = page_folio(page); struct mm_struct *mm = vma->vm_mm; - DEFINE_PAGE_VMA_WALK(pvmw, page, vma, address, 0); + DEFINE_FOLIO_VMA_WALK(pvmw, folio, vma, address, 0); pte_t pteval; struct page *subpage; bool ret = true; @@ -1436,13 +1436,13 @@ static bool try_to_unmap_one(struct page *page, struct vm_area_struct *vma, * For hugetlb, it could be much worse if we need to do pud * invalidation in the case of pmd sharing. * - * Note that the page can not be free in this function as call of - * try_to_unmap() must hold a reference on the page. + * Note that the folio can not be freed in this function as call of + * try_to_unmap() must hold a reference on the folio. */ range.end = vma_address_end(&pvmw); mmu_notifier_range_init(&range, MMU_NOTIFY_CLEAR, 0, vma, vma->vm_mm, address, range.end); - if (PageHuge(page)) { + if (folio_test_hugetlb(folio)) { /* * If sharing is possible, start and end will be adjusted * accordingly. @@ -1454,24 +1454,25 @@ static bool try_to_unmap_one(struct page *page, struct vm_area_struct *vma, while (page_vma_mapped_walk(&pvmw)) { /* Unexpected PMD-mapped THP? */ - VM_BUG_ON_PAGE(!pvmw.pte, page); + VM_BUG_ON_FOLIO(!pvmw.pte, folio); /* - * If the page is in an mlock()d vma, we must not swap it out. + * If the folio is in an mlock()d vma, we must not swap it out. */ if (!(flags & TTU_IGNORE_MLOCK) && (vma->vm_flags & VM_LOCKED)) { /* Restore the mlock which got missed */ - mlock_vma_page(page, vma, false); + mlock_vma_folio(folio, vma, false); page_vma_mapped_walk_done(&pvmw); ret = false; break; } - subpage = page - page_to_pfn(page) + pte_pfn(*pvmw.pte); + subpage = folio_page(folio, + pte_pfn(*pvmw.pte) - folio_pfn(folio)); address = pvmw.address; - if (PageHuge(page) && !PageAnon(page)) { + if (folio_test_hugetlb(folio) && !folio_test_anon(folio)) { /* * To call huge_pmd_unshare, i_mmap_rwsem must be * held in write mode. Caller needs to explicitly @@ -1510,7 +1511,7 @@ static bool try_to_unmap_one(struct page *page, struct vm_area_struct *vma, if (should_defer_flush(mm, flags)) { /* * We clear the PTE but do not flush so potentially - * a remote CPU could still be writing to the page. + * a remote CPU could still be writing to the folio. * If the entry was previously clean then the * architecture must guarantee that a clear->dirty * transition on a cached TLB entry is written through @@ -1523,22 +1524,22 @@ static bool try_to_unmap_one(struct page *page, struct vm_area_struct *vma, pteval = ptep_clear_flush(vma, address, pvmw.pte); } - /* Move the dirty bit to the page. Now the pte is gone. */ + /* Set the dirty flag on the folio now the pte is gone. */ if (pte_dirty(pteval)) - set_page_dirty(page); + folio_mark_dirty(folio); /* Update high watermark before we lower rss */ update_hiwater_rss(mm); - if (PageHWPoison(page) && !(flags & TTU_IGNORE_HWPOISON)) { + if (PageHWPoison(subpage) && !(flags & TTU_IGNORE_HWPOISON)) { pteval = swp_entry_to_pte(make_hwpoison_entry(subpage)); - if (PageHuge(page)) { - hugetlb_count_sub(compound_nr(page), mm); + if (folio_test_hugetlb(folio)) { + hugetlb_count_sub(folio_nr_pages(folio), mm); set_huge_swap_pte_at(mm, address, pvmw.pte, pteval, vma_mmu_pagesize(vma)); } else { - dec_mm_counter(mm, mm_counter(page)); + dec_mm_counter(mm, mm_counter(&folio->page)); set_pte_at(mm, address, pvmw.pte, pteval); } @@ -1553,18 +1554,19 @@ static bool try_to_unmap_one(struct page *page, struct vm_area_struct *vma, * migration) will not expect userfaults on already * copied pages. */ - dec_mm_counter(mm, mm_counter(page)); + dec_mm_counter(mm, mm_counter(&folio->page)); /* We have to invalidate as we cleared the pte */ mmu_notifier_invalidate_range(mm, address, address + PAGE_SIZE); - } else if (PageAnon(page)) { + } else if (folio_test_anon(folio)) { swp_entry_t entry = { .val = page_private(subpage) }; pte_t swp_pte; /* * Store the swap location in the pte. * See handle_pte_fault() ... */ - if (unlikely(PageSwapBacked(page) != PageSwapCache(page))) { + if (unlikely(folio_test_swapbacked(folio) != + folio_test_swapcache(folio))) { WARN_ON_ONCE(1); ret = false; /* We have to invalidate as we cleared the pte */ @@ -1575,8 +1577,8 @@ static bool try_to_unmap_one(struct page *page, struct vm_area_struct *vma, } /* MADV_FREE page check */ - if (!PageSwapBacked(page)) { - if (!PageDirty(page)) { + if (!folio_test_swapbacked(folio)) { + if (!folio_test_dirty(folio)) { /* Invalidate as we cleared the pte */ mmu_notifier_invalidate_range(mm, address, address + PAGE_SIZE); @@ -1585,11 +1587,11 @@ static bool try_to_unmap_one(struct page *page, struct vm_area_struct *vma, } /* - * If the page was redirtied, it cannot be + * If the folio was redirtied, it cannot be * discarded. Remap the page to page table. */ set_pte_at(mm, address, pvmw.pte, pteval); - SetPageSwapBacked(page); + folio_set_swapbacked(folio); ret = false; page_vma_mapped_walk_done(&pvmw); break; @@ -1626,16 +1628,17 @@ static bool try_to_unmap_one(struct page *page, struct vm_area_struct *vma, address + PAGE_SIZE); } else { /* - * This is a locked file-backed page, thus it cannot - * be removed from the page cache and replaced by a new - * page before mmu_notifier_invalidate_range_end, so no - * concurrent thread might update its page table to - * point at new page while a device still is using this - * page. + * This is a locked file-backed folio, + * so it cannot be removed from the page + * cache and replaced by a new folio before + * mmu_notifier_invalidate_range_end, so no + * concurrent thread might update its page table + * to point at a new folio while a device is + * still using this folio. * * See Documentation/vm/mmu_notifier.rst */ - dec_mm_counter(mm, mm_counter_file(page)); + dec_mm_counter(mm, mm_counter_file(&folio->page)); } discard: /* @@ -1645,10 +1648,10 @@ discard: * * See Documentation/vm/mmu_notifier.rst */ - page_remove_rmap(subpage, vma, PageHuge(page)); + page_remove_rmap(subpage, vma, folio_test_hugetlb(folio)); if (vma->vm_flags & VM_LOCKED) mlock_page_drain(smp_processor_id()); - put_page(page); + folio_put(folio); } mmu_notifier_invalidate_range_end(&range); @@ -1667,17 +1670,17 @@ static int page_not_mapped(struct page *page) } /** - * try_to_unmap - try to remove all page table mappings to a page - * @page: the page to get unmapped + * try_to_unmap - Try to remove all page table mappings to a folio. + * @folio: The folio to unmap. * @flags: action and flags * * Tries to remove all the page table entries which are mapping this - * page, used in the pageout path. Caller must hold the page lock. + * folio. It is the caller's responsibility to check if the folio is + * still mapped if needed (use TTU_SYNC to prevent accounting races). * - * It is the caller's responsibility to check if the page is still - * mapped when needed (use TTU_SYNC to prevent accounting races). + * Context: Caller must hold the folio lock. */ -void try_to_unmap(struct page *page, enum ttu_flags flags) +void try_to_unmap(struct folio *folio, enum ttu_flags flags) { struct rmap_walk_control rwc = { .rmap_one = try_to_unmap_one, @@ -1687,9 +1690,9 @@ void try_to_unmap(struct page *page, enum ttu_flags flags) }; if (flags & TTU_RMAP_LOCKED) - rmap_walk_locked(page, &rwc); + rmap_walk_locked(&folio->page, &rwc); else - rmap_walk(page, &rwc); + rmap_walk(&folio->page, &rwc); } /* diff --git a/mm/vmscan.c b/mm/vmscan.c index 38f124c41bcd..a57eb747f08d 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -1768,7 +1768,7 @@ retry: if (unlikely(PageTransHuge(page))) flags |= TTU_SPLIT_HUGE_PMD; - try_to_unmap(page, flags); + try_to_unmap(folio, flags); if (page_mapped(page)) { stat->nr_unmap_fail += nr_pages; if (!was_swapbacked && PageSwapBacked(page)) -- 2.11.0