diff options
author | Linus Torvalds | 2022-03-22 17:03:12 -0700 |
---|---|---|
committer | Linus Torvalds | 2022-03-22 17:03:12 -0700 |
commit | 9030fb0bb9d607908d51f9ee02efdbe01da355ee (patch) | |
tree | 9ee1d9d47fbb4b30c7f5cbc291432e666e58967a /mm/huge_memory.c | |
parent | 3bf03b9a0839c9fb06927ae53ebd0f960b19d408 (diff) | |
parent | 2a3c4bce3edb0d54983384aa8a88c0da330638f4 (diff) |
Merge tag 'folio-5.18c' of git://git.infradead.org/users/willy/pagecache
Pull folio updates from Matthew Wilcox:
- Rewrite how munlock works to massively reduce the contention on
i_mmap_rwsem (Hugh Dickins):
https://lore.kernel.org/linux-mm/8e4356d-9622-a7f0-b2c-f116b5f2efea@google.com/
- Sort out the page refcount mess for ZONE_DEVICE pages (Christoph
Hellwig):
https://lore.kernel.org/linux-mm/20220210072828.2930359-1-hch@lst.de/
- Convert GUP to use folios and make pincount available for order-1
pages. (Matthew Wilcox)
- Convert a few more truncation functions to use folios (Matthew
Wilcox)
- Convert page_vma_mapped_walk to use PFNs instead of pages (Matthew
Wilcox)
- Convert rmap_walk to use folios (Matthew Wilcox)
- Convert most of shrink_page_list() to use a folio (Matthew Wilcox)
- Add support for creating large folios in readahead (Matthew Wilcox)
* tag 'folio-5.18c' of git://git.infradead.org/users/willy/pagecache: (114 commits)
mm/damon: minor cleanup for damon_pa_young
selftests/vm/transhuge-stress: Support file-backed PMD folios
mm/filemap: Support VM_HUGEPAGE for file mappings
mm/readahead: Switch to page_cache_ra_order
mm/readahead: Align file mappings for non-DAX
mm/readahead: Add large folio readahead
mm: Support arbitrary THP sizes
mm: Make large folios depend on THP
mm: Fix READ_ONLY_THP warning
mm/filemap: Allow large folios to be added to the page cache
mm: Turn can_split_huge_page() into can_split_folio()
mm/vmscan: Convert pageout() to take a folio
mm/vmscan: Turn page_check_references() into folio_check_references()
mm/vmscan: Account large folios correctly
mm/vmscan: Optimise shrink_page_list for non-PMD-sized folios
mm/vmscan: Free non-shmem folios without splitting them
mm/rmap: Constify the rmap_walk_control argument
mm/rmap: Convert rmap_walk() to take a folio
mm: Turn page_anon_vma() into folio_anon_vma()
mm/rmap: Turn page_lock_anon_vma_read() into folio_lock_anon_vma_read()
...
Diffstat (limited to 'mm/huge_memory.c')
-rw-r--r-- | mm/huge_memory.c | 178 |
1 files changed, 62 insertions, 116 deletions
diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 88c83c84325c..005fab2f3b73 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -583,13 +583,10 @@ unsigned long thp_get_unmapped_area(struct file *filp, unsigned long addr, unsigned long ret; loff_t off = (loff_t)pgoff << PAGE_SHIFT; - if (!IS_DAX(filp->f_mapping->host) || !IS_ENABLED(CONFIG_FS_DAX_PMD)) - goto out; - ret = __thp_get_unmapped_area(filp, addr, len, off, flags, PMD_SIZE); if (ret) return ret; -out: + return current->mm->get_unmapped_area(filp, addr, len, pgoff, flags); } EXPORT_SYMBOL_GPL(thp_get_unmapped_area); @@ -1381,39 +1378,6 @@ struct page *follow_trans_huge_pmd(struct vm_area_struct *vma, if (flags & FOLL_TOUCH) touch_pmd(vma, addr, pmd, flags); - if ((flags & FOLL_MLOCK) && (vma->vm_flags & VM_LOCKED)) { - /* - * We don't mlock() pte-mapped THPs. This way we can avoid - * leaking mlocked pages into non-VM_LOCKED VMAs. - * - * For anon THP: - * - * In most cases the pmd is the only mapping of the page as we - * break COW for the mlock() -- see gup_flags |= FOLL_WRITE for - * writable private mappings in populate_vma_page_range(). - * - * The only scenario when we have the page shared here is if we - * mlocking read-only mapping shared over fork(). We skip - * mlocking such pages. - * - * For file THP: - * - * We can expect PageDoubleMap() to be stable under page lock: - * for file pages we set it in page_add_file_rmap(), which - * requires page to be locked. - */ - - if (PageAnon(page) && compound_mapcount(page) != 1) - goto skip_mlock; - if (PageDoubleMap(page) || !page->mapping) - goto skip_mlock; - if (!trylock_page(page)) - goto skip_mlock; - if (page->mapping && !PageDoubleMap(page)) - mlock_vma_page(page); - unlock_page(page); - } -skip_mlock: page += (addr & ~HPAGE_PMD_MASK) >> PAGE_SHIFT; VM_BUG_ON_PAGE(!PageCompound(page) && !is_zone_device_page(page), page); @@ -1611,7 +1575,7 @@ int zap_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma, if (pmd_present(orig_pmd)) { page = pmd_page(orig_pmd); - page_remove_rmap(page, true); + page_remove_rmap(page, vma, true); VM_BUG_ON_PAGE(page_mapcount(page) < 0, page); VM_BUG_ON_PAGE(!PageHead(page), page); } else if (thp_migration_supported()) { @@ -2007,7 +1971,7 @@ static void __split_huge_pmd_locked(struct vm_area_struct *vma, pmd_t *pmd, set_page_dirty(page); if (!PageReferenced(page) && pmd_young(old_pmd)) SetPageReferenced(page); - page_remove_rmap(page, true); + page_remove_rmap(page, vma, true); put_page(page); } add_mm_counter(mm, mm_counter_file(page), -HPAGE_PMD_NR); @@ -2141,6 +2105,9 @@ static void __split_huge_pmd_locked(struct vm_area_struct *vma, pmd_t *pmd, } } unlock_page_memcg(page); + + /* Above is effectively page_remove_rmap(page, vma, true) */ + munlock_vma_page(page, vma, true); } smp_wmb(); /* make pte visible before pmd */ @@ -2148,18 +2115,18 @@ static void __split_huge_pmd_locked(struct vm_area_struct *vma, pmd_t *pmd, if (freeze) { for (i = 0; i < HPAGE_PMD_NR; i++) { - page_remove_rmap(page + i, false); + page_remove_rmap(page + i, vma, false); put_page(page + i); } } } void __split_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd, - unsigned long address, bool freeze, struct page *page) + unsigned long address, bool freeze, struct folio *folio) { spinlock_t *ptl; struct mmu_notifier_range range; - bool do_unlock_page = false; + bool do_unlock_folio = false; pmd_t _pmd; mmu_notifier_range_init(&range, MMU_NOTIFY_CLEAR, 0, vma, vma->vm_mm, @@ -2169,20 +2136,20 @@ void __split_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd, ptl = pmd_lock(vma->vm_mm, pmd); /* - * If caller asks to setup a migration entries, we need a page to check - * pmd against. Otherwise we can end up replacing wrong page. + * If caller asks to setup a migration entry, we need a folio to check + * pmd against. Otherwise we can end up replacing wrong folio. */ - VM_BUG_ON(freeze && !page); - if (page) { - VM_WARN_ON_ONCE(!PageLocked(page)); - if (page != pmd_page(*pmd)) + VM_BUG_ON(freeze && !folio); + if (folio) { + VM_WARN_ON_ONCE(!folio_test_locked(folio)); + if (folio != page_folio(pmd_page(*pmd))) goto out; } repeat: if (pmd_trans_huge(*pmd)) { - if (!page) { - page = pmd_page(*pmd); + if (!folio) { + folio = page_folio(pmd_page(*pmd)); /* * An anonymous page must be locked, to ensure that a * concurrent reuse_swap_page() sees stable mapcount; @@ -2190,33 +2157,31 @@ repeat: * and page lock must not be taken when zap_pmd_range() * calls __split_huge_pmd() while i_mmap_lock is held. */ - if (PageAnon(page)) { - if (unlikely(!trylock_page(page))) { - get_page(page); + if (folio_test_anon(folio)) { + if (unlikely(!folio_trylock(folio))) { + folio_get(folio); _pmd = *pmd; spin_unlock(ptl); - lock_page(page); + folio_lock(folio); spin_lock(ptl); if (unlikely(!pmd_same(*pmd, _pmd))) { - unlock_page(page); - put_page(page); - page = NULL; + folio_unlock(folio); + folio_put(folio); + folio = NULL; goto repeat; } - put_page(page); + folio_put(folio); } - do_unlock_page = true; + do_unlock_folio = true; } } - if (PageMlocked(page)) - clear_page_mlock(page); } else if (!(pmd_devmap(*pmd) || is_pmd_migration_entry(*pmd))) goto out; __split_huge_pmd_locked(vma, pmd, range.start, freeze); out: spin_unlock(ptl); - if (do_unlock_page) - unlock_page(page); + if (do_unlock_folio) + folio_unlock(folio); /* * No need to double call mmu_notifier->invalidate_range() callback. * They are 3 cases to consider inside __split_huge_pmd_locked(): @@ -2234,7 +2199,7 @@ out: } void split_huge_pmd_address(struct vm_area_struct *vma, unsigned long address, - bool freeze, struct page *page) + bool freeze, struct folio *folio) { pgd_t *pgd; p4d_t *p4d; @@ -2255,7 +2220,7 @@ void split_huge_pmd_address(struct vm_area_struct *vma, unsigned long address, pmd = pmd_offset(pud, address); - __split_huge_pmd(vma, pmd, address, freeze, page); + __split_huge_pmd(vma, pmd, address, freeze, folio); } static inline void split_huge_pmd_if_needed(struct vm_area_struct *vma, unsigned long address) @@ -2295,6 +2260,7 @@ 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; @@ -2305,26 +2271,27 @@ static void unmap_page(struct page *page) * pages can simply be left unmapped, then faulted back on demand. * If that is ever changed (perhaps for mlock), update remap_page(). */ - if (PageAnon(page)) - try_to_migrate(page, ttu_flags); + if (folio_test_anon(folio)) + try_to_migrate(folio, 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); } -static void remap_page(struct page *page, unsigned int nr) +static void remap_page(struct folio *folio, unsigned long nr) { - int i; + int i = 0; /* If unmap_page() uses try_to_migrate() on file, remove this check */ - if (!PageAnon(page)) + if (!folio_test_anon(folio)) return; - if (PageTransHuge(page)) { - remove_migration_ptes(page, page, true); - } else { - for (i = 0; i < nr; i++) - remove_migration_ptes(page + i, page + i, true); + for (;;) { + remove_migration_ptes(folio, folio, true); + i += folio_nr_pages(folio); + if (i >= nr) + break; + folio = folio_next(folio); } } @@ -2344,8 +2311,11 @@ static void lru_add_page_tail(struct page *head, struct page *tail, } else { /* head is still on lru (and we have it frozen) */ VM_WARN_ON(!PageLRU(head)); + if (PageUnevictable(tail)) + tail->mlock_count = 0; + else + list_add_tail(&tail->lru, &head->lru); SetPageLRU(tail); - list_add_tail(&tail->lru, &head->lru); } } @@ -2481,7 +2451,7 @@ static void __split_huge_page(struct page *page, struct list_head *list, } local_irq_enable(); - remap_page(head, nr); + remap_page(folio, nr); if (PageSwapCache(head)) { swp_entry_t entry = { .val = page_private(head) }; @@ -2506,30 +2476,6 @@ static void __split_huge_page(struct page *page, struct list_head *list, } } -int total_mapcount(struct page *page) -{ - int i, compound, nr, ret; - - VM_BUG_ON_PAGE(PageTail(page), page); - - if (likely(!PageCompound(page))) - return atomic_read(&page->_mapcount) + 1; - - compound = compound_mapcount(page); - nr = compound_nr(page); - if (PageHuge(page)) - return compound; - ret = compound; - for (i = 0; i < nr; i++) - ret += atomic_read(&page[i]._mapcount) + 1; - /* File pages has compound_mapcount included in _mapcount */ - if (!PageAnon(page)) - return ret - compound * nr; - if (PageDoubleMap(page)) - ret -= nr; - return ret; -} - /* * This calculates accurately how many mappings a transparent hugepage * has (unlike page_mapcount() which isn't fully accurate). This full @@ -2579,18 +2525,19 @@ int page_trans_huge_mapcount(struct page *page) } /* Racy check whether the huge page can be split */ -bool can_split_huge_page(struct page *page, int *pextra_pins) +bool can_split_folio(struct folio *folio, int *pextra_pins) { int extra_pins; /* Additional pins from page cache */ - if (PageAnon(page)) - extra_pins = PageSwapCache(page) ? thp_nr_pages(page) : 0; + if (folio_test_anon(folio)) + extra_pins = folio_test_swapcache(folio) ? + folio_nr_pages(folio) : 0; else - extra_pins = thp_nr_pages(page); + extra_pins = folio_nr_pages(folio); if (pextra_pins) *pextra_pins = extra_pins; - return total_mapcount(page) == page_count(page) - extra_pins - 1; + return folio_mapcount(folio) == folio_ref_count(folio) - extra_pins - 1; } /* @@ -2614,7 +2561,8 @@ bool can_split_huge_page(struct page *page, int *pextra_pins) */ int split_huge_page_to_list(struct page *page, struct list_head *list) { - struct page *head = compound_head(page); + struct folio *folio = page_folio(page); + struct page *head = &folio->page; struct deferred_split *ds_queue = get_deferred_split_queue(head); XA_STATE(xas, &head->mapping->i_pages, head->index); struct anon_vma *anon_vma = NULL; @@ -2634,7 +2582,7 @@ int split_huge_page_to_list(struct page *page, struct list_head *list) * The caller does not necessarily hold an mmap_lock that would * prevent the anon_vma disappearing so we first we take a * reference to it and then lock the anon_vma for write. This - * is similar to page_lock_anon_vma_read except the write lock + * is similar to folio_lock_anon_vma_read except the write lock * is taken to serialise against parallel split or collapse * operations. */ @@ -2681,7 +2629,7 @@ int split_huge_page_to_list(struct page *page, struct list_head *list) * Racy check if we can split the page, before unmap_page() will * split PMDs */ - if (!can_split_huge_page(head, &extra_pins)) { + if (!can_split_folio(folio, &extra_pins)) { ret = -EBUSY; goto out_unlock; } @@ -2731,7 +2679,7 @@ fail: if (mapping) xas_unlock(&xas); local_irq_enable(); - remap_page(head, thp_nr_pages(head)); + remap_page(folio, folio_nr_pages(folio)); ret = -EBUSY; } @@ -2988,7 +2936,7 @@ static int split_huge_pages_pid(int pid, unsigned long vaddr_start, goto next; total++; - if (!can_split_huge_page(compound_head(page), NULL)) + if (!can_split_folio(page_folio(page), NULL)) goto next; if (!trylock_page(page)) @@ -3181,7 +3129,7 @@ void set_pmd_migration_entry(struct page_vma_mapped_walk *pvmw, if (pmd_soft_dirty(pmdval)) pmdswp = pmd_swp_mksoft_dirty(pmdswp); set_pmd_at(mm, address, pvmw->pmd, pmdswp); - page_remove_rmap(page, true); + page_remove_rmap(page, vma, true); put_page(page); } @@ -3210,10 +3158,8 @@ void remove_migration_pmd(struct page_vma_mapped_walk *pvmw, struct page *new) if (PageAnon(new)) page_add_anon_rmap(new, vma, mmun_start, true); else - page_add_file_rmap(new, true); + page_add_file_rmap(new, vma, true); set_pmd_at(mm, mmun_start, pvmw->pmd, pmde); - if ((vma->vm_flags & VM_LOCKED) && !PageDoubleMap(new)) - mlock_vma_page(new); /* No need to invalidate - it was non-present before */ update_mmu_cache_pmd(vma, address, pvmw->pmd); |