diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2017-11-15 19:42:40 -0800 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2017-11-15 19:42:40 -0800 |
commit | 7c225c69f86c934e3be9be63ecde754e286838d7 (patch) | |
tree | ff2df419b0c4886b37407235f7d21215e4cf45e4 /mm/rmap.c | |
parent | 6363b3f3ac5be096d08c8c504128befa0c033529 (diff) | |
parent | 1b7176aea0a924ac59c6a283129d3e8eb00aa915 (diff) |
Merge branch 'akpm' (patches from Andrew)
Merge updates from Andrew Morton:
- a few misc bits
- ocfs2 updates
- almost all of MM
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (131 commits)
memory hotplug: fix comments when adding section
mm: make alloc_node_mem_map a void call if we don't have CONFIG_FLAT_NODE_MEM_MAP
mm: simplify nodemask printing
mm,oom_reaper: remove pointless kthread_run() error check
mm/page_ext.c: check if page_ext is not prepared
writeback: remove unused function parameter
mm: do not rely on preempt_count in print_vma_addr
mm, sparse: do not swamp log with huge vmemmap allocation failures
mm/hmm: remove redundant variable align_end
mm/list_lru.c: mark expected switch fall-through
mm/shmem.c: mark expected switch fall-through
mm/page_alloc.c: broken deferred calculation
mm: don't warn about allocations which stall for too long
fs: fuse: account fuse_inode slab memory as reclaimable
mm, page_alloc: fix potential false positive in __zone_watermark_ok
mm: mlock: remove lru_add_drain_all()
mm, sysctl: make NUMA stats configurable
shmem: convert shmem_init_inodecache() to void
Unify migrate_pages and move_pages access checks
mm, pagevec: rename pagevec drained field
...
Diffstat (limited to 'mm/rmap.c')
-rw-r--r-- | mm/rmap.c | 65 |
1 files changed, 55 insertions, 10 deletions
diff --git a/mm/rmap.c b/mm/rmap.c index b874c4761e84..47db27f8049e 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -899,7 +899,7 @@ static bool page_mkclean_one(struct page *page, struct vm_area_struct *vma, mmu_notifier_invalidate_range_start(vma->vm_mm, start, end); while (page_vma_mapped_walk(&pvmw)) { - unsigned long cstart, cend; + unsigned long cstart; int ret = 0; cstart = address = pvmw.address; @@ -915,7 +915,6 @@ static bool page_mkclean_one(struct page *page, struct vm_area_struct *vma, entry = pte_wrprotect(entry); entry = pte_mkclean(entry); set_pte_at(vma->vm_mm, address, pte, entry); - cend = cstart + PAGE_SIZE; ret = 1; } else { #ifdef CONFIG_TRANSPARENT_HUGE_PAGECACHE @@ -931,7 +930,6 @@ static bool page_mkclean_one(struct page *page, struct vm_area_struct *vma, entry = pmd_mkclean(entry); set_pmd_at(vma->vm_mm, address, pmd, entry); cstart &= PMD_MASK; - cend = cstart + PMD_SIZE; ret = 1; #else /* unexpected pmd-mapped page? */ @@ -939,10 +937,15 @@ static bool page_mkclean_one(struct page *page, struct vm_area_struct *vma, #endif } - if (ret) { - mmu_notifier_invalidate_range(vma->vm_mm, cstart, cend); + /* + * No need to call mmu_notifier_invalidate_range() as we are + * downgrading page table protection not changing it to point + * to a new page. + * + * See Documentation/vm/mmu_notifier.txt + */ + if (ret) (*cleaned)++; - } } mmu_notifier_invalidate_range_end(vma->vm_mm, start, end); @@ -1318,7 +1321,7 @@ void page_remove_rmap(struct page *page, bool compound) * It would be tidy to reset the PageAnon mapping here, * but that might overwrite a racing page_add_anon_rmap * which increments mapcount after us but sets mapping - * before us: so leave the reset to free_hot_cold_page, + * before us: so leave the reset to free_unref_page, * and remember that it's only reliable while mapped. * Leaving it set also helps swapoff to reinstate ptes * faster for those pages still in swapcache. @@ -1426,6 +1429,10 @@ static bool try_to_unmap_one(struct page *page, struct vm_area_struct *vma, if (pte_soft_dirty(pteval)) swp_pte = pte_swp_mksoft_dirty(swp_pte); set_pte_at(mm, pvmw.address, pvmw.pte, swp_pte); + /* + * No need to invalidate here it will synchronize on + * against the special swap migration pte. + */ goto discard; } @@ -1483,6 +1490,9 @@ static bool try_to_unmap_one(struct page *page, struct vm_area_struct *vma, * will take care of the rest. */ dec_mm_counter(mm, mm_counter(page)); + /* We have to invalidate as we cleared the pte */ + mmu_notifier_invalidate_range(mm, address, + address + PAGE_SIZE); } else if (IS_ENABLED(CONFIG_MIGRATION) && (flags & (TTU_MIGRATION|TTU_SPLIT_FREEZE))) { swp_entry_t entry; @@ -1498,6 +1508,10 @@ static bool try_to_unmap_one(struct page *page, struct vm_area_struct *vma, if (pte_soft_dirty(pteval)) swp_pte = pte_swp_mksoft_dirty(swp_pte); set_pte_at(mm, address, pvmw.pte, swp_pte); + /* + * No need to invalidate here it will synchronize on + * against the special swap migration pte. + */ } else if (PageAnon(page)) { swp_entry_t entry = { .val = page_private(subpage) }; pte_t swp_pte; @@ -1509,6 +1523,8 @@ static bool try_to_unmap_one(struct page *page, struct vm_area_struct *vma, WARN_ON_ONCE(1); ret = false; /* We have to invalidate as we cleared the pte */ + mmu_notifier_invalidate_range(mm, address, + address + PAGE_SIZE); page_vma_mapped_walk_done(&pvmw); break; } @@ -1516,6 +1532,9 @@ static bool try_to_unmap_one(struct page *page, struct vm_area_struct *vma, /* MADV_FREE page check */ if (!PageSwapBacked(page)) { if (!PageDirty(page)) { + /* Invalidate as we cleared the pte */ + mmu_notifier_invalidate_range(mm, + address, address + PAGE_SIZE); dec_mm_counter(mm, MM_ANONPAGES); goto discard; } @@ -1549,13 +1568,39 @@ static bool try_to_unmap_one(struct page *page, struct vm_area_struct *vma, if (pte_soft_dirty(pteval)) swp_pte = pte_swp_mksoft_dirty(swp_pte); set_pte_at(mm, address, pvmw.pte, swp_pte); - } else + /* Invalidate as we cleared the pte */ + mmu_notifier_invalidate_range(mm, address, + address + PAGE_SIZE); + } else { + /* + * We should not need to notify here as we reach this + * case only from freeze_page() itself only call from + * split_huge_page_to_list() so everything below must + * be true: + * - page is not anonymous + * - page is locked + * + * So as it is a locked file back page thus it can not + * be remove from the page cache and replace 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. + * + * See Documentation/vm/mmu_notifier.txt + */ dec_mm_counter(mm, mm_counter_file(page)); + } discard: + /* + * No need to call mmu_notifier_invalidate_range() it has be + * done above for all cases requiring it to happen under page + * table lock before mmu_notifier_invalidate_range_end() + * + * See Documentation/vm/mmu_notifier.txt + */ page_remove_rmap(subpage, PageHuge(page)); put_page(page); - mmu_notifier_invalidate_range(mm, address, - address + PAGE_SIZE); } mmu_notifier_invalidate_range_end(vma->vm_mm, start, end); |