We would need to use multi-order radix-tree entires for ext4 and other filesystems to have coherent view on tags (dirty/towrite) in the tree.
This patch converts huge tmpfs implementation to multi-order entries, so we will be able to use the same code patch for all filesystems. We also change interface for page-cache lookup function: - functions that lookup for pages[1] would return subpages of THP relevant for requested indexes; - functions that lookup for entries[2] would return one entry per-THP and index will point to index of head page (basically, round down to HPAGE_PMD_NR); This would provide balanced exposure of multi-order entires to the rest of the kernel. [1] find_get_pages(), pagecache_get_page(), pagevec_lookup(), etc. [2] find_get_entry(), find_get_entries(), pagevec_lookup_entries(), etc. Signed-off-by: Kirill A. Shutemov <kirill.shute...@linux.intel.com> --- include/linux/pagemap.h | 9 ++ mm/filemap.c | 236 ++++++++++++++++++++++++++---------------------- mm/huge_memory.c | 48 +++++++--- mm/khugepaged.c | 26 ++---- mm/shmem.c | 117 ++++++++++-------------- mm/truncate.c | 15 ++- 6 files changed, 235 insertions(+), 216 deletions(-) diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index 324c8dbad1e1..ad63a7be5a5e 100644 --- a/include/linux/pagemap.h +++ b/include/linux/pagemap.h @@ -332,6 +332,15 @@ static inline struct page *grab_cache_page_nowait(struct address_space *mapping, mapping_gfp_mask(mapping)); } +static inline struct page *find_subpage(struct page *page, pgoff_t offset) +{ + VM_BUG_ON_PAGE(PageTail(page), page); + VM_BUG_ON_PAGE(page->index > offset, page); + VM_BUG_ON_PAGE(page->index + (1 << compound_order(page)) < offset, + page); + return page - page->index + offset; +} + struct page *find_get_entry(struct address_space *mapping, pgoff_t offset); struct page *find_lock_entry(struct address_space *mapping, pgoff_t offset); unsigned find_get_entries(struct address_space *mapping, pgoff_t start, diff --git a/mm/filemap.c b/mm/filemap.c index b772a33ef640..837a71a2a412 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -150,7 +150,9 @@ static int page_cache_tree_insert(struct address_space *mapping, static void page_cache_tree_delete(struct address_space *mapping, struct page *page, void *shadow) { - int i, nr; + struct radix_tree_node *node; + void **slot; + int nr; /* hugetlb pages are represented by one entry in the radix tree */ nr = PageHuge(page) ? 1 : hpage_nr_pages(page); @@ -159,19 +161,12 @@ static void page_cache_tree_delete(struct address_space *mapping, VM_BUG_ON_PAGE(PageTail(page), page); VM_BUG_ON_PAGE(nr != 1 && shadow, page); - for (i = 0; i < nr; i++) { - struct radix_tree_node *node; - void **slot; + __radix_tree_lookup(&mapping->page_tree, page->index, &node, &slot); + VM_BUG_ON_PAGE(!node && nr != 1, page); - __radix_tree_lookup(&mapping->page_tree, page->index + i, - &node, &slot); - - VM_BUG_ON_PAGE(!node && nr != 1, page); - - radix_tree_clear_tags(&mapping->page_tree, node, slot); - __radix_tree_replace(&mapping->page_tree, node, slot, shadow, - workingset_update_node, mapping); - } + radix_tree_clear_tags(&mapping->page_tree, node, slot); + __radix_tree_replace(&mapping->page_tree, node, slot, shadow, + workingset_update_node, mapping); if (shadow) { mapping->nrexceptional += nr; @@ -285,12 +280,7 @@ void delete_from_page_cache(struct page *page) if (freepage) freepage(page); - if (PageTransHuge(page) && !PageHuge(page)) { - page_ref_sub(page, HPAGE_PMD_NR); - VM_BUG_ON_PAGE(page_count(page) <= 0, page); - } else { - put_page(page); - } + put_page(page); } EXPORT_SYMBOL(delete_from_page_cache); @@ -1172,7 +1162,7 @@ EXPORT_SYMBOL(page_cache_prev_hole); struct page *find_get_entry(struct address_space *mapping, pgoff_t offset) { void **pagep; - struct page *head, *page; + struct page *page; rcu_read_lock(); repeat: @@ -1193,15 +1183,8 @@ struct page *find_get_entry(struct address_space *mapping, pgoff_t offset) goto out; } - head = compound_head(page); - if (!page_cache_get_speculative(head)) - goto repeat; - - /* The page was split under us? */ - if (compound_head(page) != head) { - put_page(head); + if (!page_cache_get_speculative(page)) goto repeat; - } /* * Has the page moved? @@ -1209,7 +1192,7 @@ struct page *find_get_entry(struct address_space *mapping, pgoff_t offset) * include/linux/pagemap.h for details. */ if (unlikely(page != *pagep)) { - put_page(head); + put_page(page); goto repeat; } } @@ -1250,7 +1233,6 @@ struct page *find_lock_entry(struct address_space *mapping, pgoff_t offset) put_page(page); goto repeat; } - VM_BUG_ON_PAGE(page_to_pgoff(page) != offset, page); } return page; } @@ -1307,7 +1289,6 @@ struct page *pagecache_get_page(struct address_space *mapping, pgoff_t offset, put_page(page); goto repeat; } - VM_BUG_ON_PAGE(page->index != offset, page); } if (page && (fgp_flags & FGP_ACCESSED)) @@ -1342,6 +1323,8 @@ struct page *pagecache_get_page(struct address_space *mapping, pgoff_t offset, } } + if (page) + page = find_subpage(page, offset); return page; } EXPORT_SYMBOL(pagecache_get_page); @@ -1382,7 +1365,7 @@ unsigned find_get_entries(struct address_space *mapping, rcu_read_lock(); radix_tree_for_each_slot(slot, &mapping->page_tree, &iter, start) { - struct page *head, *page; + struct page *page; repeat: page = radix_tree_deref_slot(slot); if (unlikely(!page)) @@ -1400,19 +1383,12 @@ unsigned find_get_entries(struct address_space *mapping, goto export; } - head = compound_head(page); - if (!page_cache_get_speculative(head)) + if (!page_cache_get_speculative(page)) goto repeat; - /* The page was split under us? */ - if (compound_head(page) != head) { - put_page(head); - goto repeat; - } - /* Has the page moved? */ if (unlikely(page != *slot)) { - put_page(head); + put_page(page); goto repeat; } export: @@ -1446,14 +1422,17 @@ unsigned find_get_pages(struct address_space *mapping, pgoff_t start, { struct radix_tree_iter iter; void **slot; - unsigned ret = 0; + unsigned refs, ret = 0; if (unlikely(!nr_pages)) return 0; rcu_read_lock(); radix_tree_for_each_slot(slot, &mapping->page_tree, &iter, start) { - struct page *head, *page; + struct page *page; + unsigned long index = iter.index; + if (index < start) + index = start; repeat: page = radix_tree_deref_slot(slot); if (unlikely(!page)) @@ -1472,25 +1451,35 @@ unsigned find_get_pages(struct address_space *mapping, pgoff_t start, continue; } - head = compound_head(page); - if (!page_cache_get_speculative(head)) - goto repeat; - - /* The page was split under us? */ - if (compound_head(page) != head) { - put_page(head); + if (!page_cache_get_speculative(page)) goto repeat; - } /* Has the page moved? */ if (unlikely(page != *slot)) { - put_page(head); + put_page(page); goto repeat; } + /* For multi-order entries, find relevant subpage */ + if (PageTransHuge(page)) { + VM_BUG_ON(index - page->index < 0); + VM_BUG_ON(index - page->index >= HPAGE_PMD_NR); + page += index - page->index; + } + pages[ret] = page; if (++ret == nr_pages) break; + if (!PageTransCompound(page)) + continue; + for (refs = 0; ret < nr_pages && + (index + 1) % HPAGE_PMD_NR; + ret++, refs++, index++) + pages[ret] = ++page; + if (refs) + page_ref_add(compound_head(page), refs); + if (ret == nr_pages) + break; } rcu_read_unlock(); @@ -1500,7 +1489,7 @@ unsigned find_get_pages(struct address_space *mapping, pgoff_t start, /** * find_get_pages_contig - gang contiguous pagecache lookup * @mapping: The address_space to search - * @index: The starting page index + * @start: The starting page index * @nr_pages: The maximum number of pages * @pages: Where the resulting pages are placed * @@ -1509,19 +1498,22 @@ unsigned find_get_pages(struct address_space *mapping, pgoff_t start, * * find_get_pages_contig() returns the number of pages which were found. */ -unsigned find_get_pages_contig(struct address_space *mapping, pgoff_t index, +unsigned find_get_pages_contig(struct address_space *mapping, pgoff_t start, unsigned int nr_pages, struct page **pages) { struct radix_tree_iter iter; void **slot; - unsigned int ret = 0; + unsigned int refs, ret = 0; if (unlikely(!nr_pages)) return 0; rcu_read_lock(); - radix_tree_for_each_contig(slot, &mapping->page_tree, &iter, index) { - struct page *head, *page; + radix_tree_for_each_contig(slot, &mapping->page_tree, &iter, start) { + struct page *page; + unsigned long index = iter.index; + if (index < start) + index = start; repeat: page = radix_tree_deref_slot(slot); /* The hole, there no reason to continue */ @@ -1541,19 +1533,12 @@ unsigned find_get_pages_contig(struct address_space *mapping, pgoff_t index, break; } - head = compound_head(page); - if (!page_cache_get_speculative(head)) + if (!page_cache_get_speculative(page)) goto repeat; - /* The page was split under us? */ - if (compound_head(page) != head) { - put_page(head); - goto repeat; - } - /* Has the page moved? */ if (unlikely(page != *slot)) { - put_page(head); + put_page(page); goto repeat; } @@ -1562,14 +1547,31 @@ unsigned find_get_pages_contig(struct address_space *mapping, pgoff_t index, * otherwise we can get both false positives and false * negatives, which is just confusing to the caller. */ - if (page->mapping == NULL || page_to_pgoff(page) != iter.index) { + if (page->mapping == NULL || page_to_pgoff(page) != index) { put_page(page); break; } + /* For multi-order entries, find relevant subpage */ + if (PageTransHuge(page)) { + VM_BUG_ON(index - page->index < 0); + VM_BUG_ON(index - page->index >= HPAGE_PMD_NR); + page += index - page->index; + } + pages[ret] = page; if (++ret == nr_pages) break; + if (!PageTransCompound(page)) + continue; + for (refs = 0; ret < nr_pages && + (index + 1) % HPAGE_PMD_NR; + ret++, refs++, index++) + pages[ret] = ++page; + if (refs) + page_ref_add(compound_head(page), refs); + if (ret == nr_pages) + break; } rcu_read_unlock(); return ret; @@ -1579,7 +1581,7 @@ EXPORT_SYMBOL(find_get_pages_contig); /** * find_get_pages_tag - find and return pages that match @tag * @mapping: the address_space to search - * @index: the starting page index + * @indexp: the starting page index * @tag: the tag index * @nr_pages: the maximum number of pages * @pages: where the resulting pages are placed @@ -1587,20 +1589,23 @@ EXPORT_SYMBOL(find_get_pages_contig); * Like find_get_pages, except we only return pages which are tagged with * @tag. We update @index to index the next page for the traversal. */ -unsigned find_get_pages_tag(struct address_space *mapping, pgoff_t *index, +unsigned find_get_pages_tag(struct address_space *mapping, pgoff_t *indexp, int tag, unsigned int nr_pages, struct page **pages) { struct radix_tree_iter iter; void **slot; - unsigned ret = 0; + unsigned refs, ret = 0; if (unlikely(!nr_pages)) return 0; rcu_read_lock(); radix_tree_for_each_tagged(slot, &mapping->page_tree, - &iter, *index, tag) { - struct page *head, *page; + &iter, *indexp, tag) { + struct page *page; + unsigned long index = iter.index; + if (index < *indexp) + index = *indexp; repeat: page = radix_tree_deref_slot(slot); if (unlikely(!page)) @@ -1625,31 +1630,41 @@ unsigned find_get_pages_tag(struct address_space *mapping, pgoff_t *index, continue; } - head = compound_head(page); - if (!page_cache_get_speculative(head)) - goto repeat; - - /* The page was split under us? */ - if (compound_head(page) != head) { - put_page(head); + if (!page_cache_get_speculative(page)) goto repeat; - } /* Has the page moved? */ if (unlikely(page != *slot)) { - put_page(head); + put_page(page); goto repeat; } + /* For multi-order entries, find relevant subpage */ + if (PageTransHuge(page)) { + VM_BUG_ON(index - page->index < 0); + VM_BUG_ON(index - page->index >= HPAGE_PMD_NR); + page += index - page->index; + } + pages[ret] = page; if (++ret == nr_pages) break; + if (!PageTransCompound(page)) + continue; + for (refs = 0; ret < nr_pages && + (index + 1) % HPAGE_PMD_NR; + ret++, refs++, index++) + pages[ret] = ++page; + if (refs) + page_ref_add(compound_head(page), refs); + if (ret == nr_pages) + break; } rcu_read_unlock(); if (ret) - *index = pages[ret - 1]->index + 1; + *indexp = page_to_pgoff(pages[ret - 1]) + 1; return ret; } @@ -1681,7 +1696,7 @@ unsigned find_get_entries_tag(struct address_space *mapping, pgoff_t start, rcu_read_lock(); radix_tree_for_each_tagged(slot, &mapping->page_tree, &iter, start, tag) { - struct page *head, *page; + struct page *page; repeat: page = radix_tree_deref_slot(slot); if (unlikely(!page)) @@ -1700,19 +1715,12 @@ unsigned find_get_entries_tag(struct address_space *mapping, pgoff_t start, goto export; } - head = compound_head(page); - if (!page_cache_get_speculative(head)) - goto repeat; - - /* The page was split under us? */ - if (compound_head(page) != head) { - put_page(head); + if (!page_cache_get_speculative(page)) goto repeat; - } /* Has the page moved? */ if (unlikely(page != *slot)) { - put_page(head); + put_page(page); goto repeat; } export: @@ -2310,12 +2318,15 @@ void filemap_map_pages(struct vm_fault *vmf, struct address_space *mapping = file->f_mapping; pgoff_t last_pgoff = start_pgoff; loff_t size; - struct page *head, *page; + struct page *page; rcu_read_lock(); radix_tree_for_each_slot(slot, &mapping->page_tree, &iter, start_pgoff) { - if (iter.index > end_pgoff) + unsigned long index = iter.index; + if (index < start_pgoff) + index = start_pgoff; + if (index > end_pgoff) break; repeat: page = radix_tree_deref_slot(slot); @@ -2326,25 +2337,26 @@ void filemap_map_pages(struct vm_fault *vmf, slot = radix_tree_iter_retry(&iter); continue; } + page = NULL; goto next; } - head = compound_head(page); - if (!page_cache_get_speculative(head)) + if (!page_cache_get_speculative(page)) goto repeat; - /* The page was split under us? */ - if (compound_head(page) != head) { - put_page(head); - goto repeat; - } - /* Has the page moved? */ if (unlikely(page != *slot)) { - put_page(head); + put_page(page); goto repeat; } + /* For multi-order entries, find relevant subpage */ + if (PageTransHuge(page)) { + VM_BUG_ON(index - page->index < 0); + VM_BUG_ON(index - page->index >= HPAGE_PMD_NR); + page += index - page->index; + } + if (!PageUptodate(page) || PageReadahead(page) || PageHWPoison(page)) @@ -2352,20 +2364,20 @@ void filemap_map_pages(struct vm_fault *vmf, if (!trylock_page(page)) goto skip; - if (page->mapping != mapping || !PageUptodate(page)) + if (page_mapping(page) != mapping || !PageUptodate(page)) goto unlock; size = round_up(i_size_read(mapping->host), PAGE_SIZE); - if (page->index >= size >> PAGE_SHIFT) + if (compound_head(page)->index >= size >> PAGE_SHIFT) goto unlock; if (file->f_ra.mmap_miss > 0) file->f_ra.mmap_miss--; - vmf->address += (iter.index - last_pgoff) << PAGE_SHIFT; + vmf->address += (index - last_pgoff) << PAGE_SHIFT; if (vmf->pte) - vmf->pte += iter.index - last_pgoff; - last_pgoff = iter.index; + vmf->pte += index - last_pgoff; + last_pgoff = index; if (alloc_set_pte(vmf, NULL, page)) goto unlock; unlock_page(page); @@ -2378,8 +2390,14 @@ void filemap_map_pages(struct vm_fault *vmf, /* Huge page is mapped? No need to proceed. */ if (pmd_trans_huge(*vmf->pmd)) break; - if (iter.index == end_pgoff) + if (index == end_pgoff) break; + if (page && PageTransCompound(page) && + (index & (HPAGE_PMD_NR - 1)) != + HPAGE_PMD_NR - 1) { + index++; + goto repeat; + } } rcu_read_unlock(); } diff --git a/mm/huge_memory.c b/mm/huge_memory.c index ca7855f857fa..f383cb801e34 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -1928,6 +1928,7 @@ static void __split_huge_page(struct page *page, struct list_head *list, struct page *head = compound_head(page); struct zone *zone = page_zone(head); struct lruvec *lruvec; + struct page *subpage; pgoff_t end = -1; int i; @@ -1936,8 +1937,27 @@ static void __split_huge_page(struct page *page, struct list_head *list, /* complete memcg works before add pages to LRU */ mem_cgroup_split_huge_fixup(head); - if (!PageAnon(page)) - end = DIV_ROUND_UP(i_size_read(head->mapping->host), PAGE_SIZE); + if (!PageAnon(head)) { + struct address_space *mapping = head->mapping; + struct radix_tree_iter iter; + void **slot; + + __dec_node_page_state(head, NR_SHMEM_THPS); + + radix_tree_split(&mapping->page_tree, head->index, 0); + radix_tree_for_each_slot(slot, &mapping->page_tree, &iter, + head->index) { + if (iter.index >= head->index + HPAGE_PMD_NR) + break; + subpage = head + iter.index - head->index; + radix_tree_replace_slot(&mapping->page_tree, + slot, subpage); + VM_BUG_ON_PAGE(compound_head(subpage) != head, subpage); + } + radix_tree_preload_end(); + + end = DIV_ROUND_UP(i_size_read(mapping->host), PAGE_SIZE); + } for (i = HPAGE_PMD_NR - 1; i >= 1; i--) { __split_huge_page_tail(head, i, lruvec, list); @@ -1966,7 +1986,7 @@ static void __split_huge_page(struct page *page, struct list_head *list, unfreeze_page(head); for (i = 0; i < HPAGE_PMD_NR; i++) { - struct page *subpage = head + i; + subpage = head + i; if (subpage == page) continue; unlock_page(subpage); @@ -2123,8 +2143,8 @@ int split_huge_page_to_list(struct page *page, struct list_head *list) goto out; } - /* Addidional pins from radix tree */ - extra_pins = HPAGE_PMD_NR; + /* Addidional pin from radix tree */ + extra_pins = 1; anon_vma = NULL; i_mmap_lock_read(mapping); } @@ -2146,6 +2166,12 @@ int split_huge_page_to_list(struct page *page, struct list_head *list) if (mlocked) lru_add_drain(); + if (mapping && radix_tree_split_preload(HPAGE_PMD_ORDER, 0, + GFP_KERNEL)) { + ret = -ENOMEM; + goto unfreeze; + } + /* prevent PageLRU to go away from under us, and freeze lru stats */ spin_lock_irqsave(zone_lru_lock(page_zone(head)), flags); @@ -2155,10 +2181,7 @@ int split_huge_page_to_list(struct page *page, struct list_head *list) spin_lock(&mapping->tree_lock); pslot = radix_tree_lookup_slot(&mapping->page_tree, page_index(head)); - /* - * Check if the head page is present in radix tree. - * We assume all tail are present too, if head is there. - */ + /* Check if the page is present in radix tree */ if (radix_tree_deref_slot_protected(pslot, &mapping->tree_lock) != head) goto fail; @@ -2173,8 +2196,6 @@ int split_huge_page_to_list(struct page *page, struct list_head *list) pgdata->split_queue_len--; list_del(page_deferred_list(head)); } - if (mapping) - __dec_node_page_state(page, NR_SHMEM_THPS); spin_unlock(&pgdata->split_queue_lock); __split_huge_page(page, list, flags); ret = 0; @@ -2188,9 +2209,12 @@ int split_huge_page_to_list(struct page *page, struct list_head *list) BUG(); } spin_unlock(&pgdata->split_queue_lock); -fail: if (mapping) +fail: if (mapping) { spin_unlock(&mapping->tree_lock); + radix_tree_preload_end(); + } spin_unlock_irqrestore(zone_lru_lock(page_zone(head)), flags); +unfreeze: unfreeze_page(head); ret = -EBUSY; } diff --git a/mm/khugepaged.c b/mm/khugepaged.c index 77ae3239c3de..1910048bf63a 100644 --- a/mm/khugepaged.c +++ b/mm/khugepaged.c @@ -1350,10 +1350,8 @@ static void collapse_shmem(struct mm_struct *mm, break; } nr_none += n; - for (; index < min(iter.index, end); index++) { - radix_tree_insert(&mapping->page_tree, index, - new_page + (index % HPAGE_PMD_NR)); - } + for (; index < min(iter.index, end); index++) + radix_tree_insert(&mapping->page_tree, index, new_page); /* We are done. */ if (index >= end) @@ -1425,8 +1423,7 @@ static void collapse_shmem(struct mm_struct *mm, list_add_tail(&page->lru, &pagelist); /* Finally, replace with the new page. */ - radix_tree_replace_slot(&mapping->page_tree, slot, - new_page + (index % HPAGE_PMD_NR)); + radix_tree_replace_slot(&mapping->page_tree, slot, new_page); slot = radix_tree_iter_resume(slot, &iter); index++; @@ -1444,24 +1441,17 @@ static void collapse_shmem(struct mm_struct *mm, break; } - /* - * Handle hole in radix tree at the end of the range. - * This code only triggers if there's nothing in radix tree - * beyond 'end'. - */ - if (result == SCAN_SUCCEED && index < end) { + if (result == SCAN_SUCCEED) { int n = end - index; - if (!shmem_charge(mapping->host, n)) { + if (n && !shmem_charge(mapping->host, n)) { result = SCAN_FAIL; goto tree_locked; } - - for (; index < end; index++) { - radix_tree_insert(&mapping->page_tree, index, - new_page + (index % HPAGE_PMD_NR)); - } nr_none += n; + + radix_tree_join(&mapping->page_tree, start, + HPAGE_PMD_ORDER, new_page); } tree_locked: diff --git a/mm/shmem.c b/mm/shmem.c index bb53285a1d99..ff017bbde4b3 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -544,33 +544,14 @@ static int shmem_add_to_page_cache(struct page *page, VM_BUG_ON_PAGE(!PageSwapBacked(page), page); VM_BUG_ON(expected && PageTransHuge(page)); - page_ref_add(page, nr); + get_page(page); page->mapping = mapping; page->index = index; spin_lock_irq(&mapping->tree_lock); - if (PageTransHuge(page)) { - void __rcu **results; - pgoff_t idx; - int i; - - error = 0; - if (radix_tree_gang_lookup_slot(&mapping->page_tree, - &results, &idx, index, 1) && - idx < index + HPAGE_PMD_NR) { - error = -EEXIST; - } - - if (!error) { - for (i = 0; i < HPAGE_PMD_NR; i++) { - error = radix_tree_insert(&mapping->page_tree, - index + i, page + i); - VM_BUG_ON(error); - } - count_vm_event(THP_FILE_ALLOC); - } - } else if (!expected) { - error = radix_tree_insert(&mapping->page_tree, index, page); + if (!expected) { + error = __radix_tree_insert(&mapping->page_tree, index, + compound_order(page), page); } else { error = shmem_radix_tree_replace(mapping, index, expected, page); @@ -578,15 +559,17 @@ static int shmem_add_to_page_cache(struct page *page, if (!error) { mapping->nrpages += nr; - if (PageTransHuge(page)) + if (PageTransHuge(page)) { + count_vm_event(THP_FILE_ALLOC); __inc_node_page_state(page, NR_SHMEM_THPS); + } __mod_node_page_state(page_pgdat(page), NR_FILE_PAGES, nr); __mod_node_page_state(page_pgdat(page), NR_SHMEM, nr); spin_unlock_irq(&mapping->tree_lock); } else { page->mapping = NULL; spin_unlock_irq(&mapping->tree_lock); - page_ref_sub(page, nr); + put_page(page); } return error; } @@ -727,8 +710,9 @@ void shmem_unlock_mapping(struct address_space *mapping) PAGEVEC_SIZE, pvec.pages, indices); if (!pvec.nr) break; - index = indices[pvec.nr - 1] + 1; pagevec_remove_exceptionals(&pvec); + index = indices[pvec.nr - 1] + + hpage_nr_pages(pvec.pages[pvec.nr - 1]); check_move_unevictable_pages(pvec.pages, pvec.nr); pagevec_release(&pvec); cond_resched(); @@ -785,23 +769,25 @@ static void shmem_undo_range(struct inode *inode, loff_t lstart, loff_t lend, if (!trylock_page(page)) continue; - if (PageTransTail(page)) { - /* Middle of THP: zero out the page */ - clear_highpage(page); - unlock_page(page); - continue; - } else if (PageTransHuge(page)) { + if (PageTransHuge(page)) { + /* Range starts in the middle of THP */ + if (start > page->index) { + pgoff_t i; + index += HPAGE_PMD_NR; + page += start - page->index; + for (i = start; i < index; i++, page++) + clear_highpage(page); + unlock_page(page - 1); + continue; + } + + /* Range ends in the middle of THP */ if (index == round_down(end, HPAGE_PMD_NR)) { - /* - * Range ends in the middle of THP: - * zero out the page - */ - clear_highpage(page); + while (index++ < end) + clear_highpage(page++); unlock_page(page); continue; } - index += HPAGE_PMD_NR - 1; - i += HPAGE_PMD_NR - 1; } if (!unfalloc || !PageUptodate(page)) { @@ -814,9 +800,9 @@ static void shmem_undo_range(struct inode *inode, loff_t lstart, loff_t lend, unlock_page(page); } pagevec_remove_exceptionals(&pvec); + index += pvec.nr ? hpage_nr_pages(pvec.pages[pvec.nr - 1]) : 1; pagevec_release(&pvec); cond_resched(); - index++; } if (partial_start) { @@ -874,8 +860,7 @@ static void shmem_undo_range(struct inode *inode, loff_t lstart, loff_t lend, continue; if (shmem_free_swap(mapping, index, page)) { /* Swap was replaced by page: retry */ - index--; - break; + goto retry; } nr_swaps_freed++; continue; @@ -883,30 +868,24 @@ static void shmem_undo_range(struct inode *inode, loff_t lstart, loff_t lend, lock_page(page); - if (PageTransTail(page)) { - /* Middle of THP: zero out the page */ - clear_highpage(page); - unlock_page(page); - /* - * Partial thp truncate due 'start' in middle - * of THP: don't need to look on these pages - * again on !pvec.nr restart. - */ - if (index != round_down(end, HPAGE_PMD_NR)) - start++; - continue; - } else if (PageTransHuge(page)) { + if (PageTransHuge(page)) { + /* Range starts in the middle of THP */ + if (start > page->index) { + index += HPAGE_PMD_NR; + page += start - page->index; + while (start++ < index) + clear_highpage(page++); + unlock_page(page - 1); + continue; + } + + /* Range ends in the middle of THP */ if (index == round_down(end, HPAGE_PMD_NR)) { - /* - * Range ends in the middle of THP: - * zero out the page - */ - clear_highpage(page); + while (index++ < end) + clear_highpage(page++); unlock_page(page); continue; } - index += HPAGE_PMD_NR - 1; - i += HPAGE_PMD_NR - 1; } if (!unfalloc || !PageUptodate(page)) { @@ -917,15 +896,18 @@ static void shmem_undo_range(struct inode *inode, loff_t lstart, loff_t lend, } else { /* Page was replaced by swap: retry */ unlock_page(page); - index--; - break; + goto retry; } } unlock_page(page); } pagevec_remove_exceptionals(&pvec); + index += pvec.nr ? hpage_nr_pages(pvec.pages[pvec.nr - 1]) : 1; + pagevec_release(&pvec); + continue; +retry: + pagevec_remove_exceptionals(&pvec); pagevec_release(&pvec); - index++; } spin_lock_irq(&info->lock); @@ -1762,8 +1744,7 @@ alloc_nohuge: page = shmem_alloc_and_acct_page(gfp, info, sbinfo, PageTransHuge(page)); if (error) goto unacct; - error = radix_tree_maybe_preload_order(gfp & GFP_RECLAIM_MASK, - compound_order(page)); + error = radix_tree_maybe_preload(gfp & GFP_RECLAIM_MASK); if (!error) { error = shmem_add_to_page_cache(page, mapping, hindex, NULL); @@ -1837,7 +1818,7 @@ alloc_nohuge: page = shmem_alloc_and_acct_page(gfp, info, sbinfo, error = -EINVAL; goto unlock; } - *pagep = page + index - hindex; + *pagep = find_subpage(page, index); return 0; /* diff --git a/mm/truncate.c b/mm/truncate.c index dd7b24e083c5..3a1a1c1a654e 100644 --- a/mm/truncate.c +++ b/mm/truncate.c @@ -524,16 +524,13 @@ unsigned long invalidate_mapping_pages(struct address_space *mapping, WARN_ON(page_to_index(page) != index); - /* Middle of THP: skip */ - if (PageTransTail(page)) { + /* Is 'start' or 'end' in the middle of THP ? */ + if (PageTransHuge(page) && + (start > index || + (index == round_down(end, HPAGE_PMD_NR)))) { + /* skip */ unlock_page(page); continue; - } else if (PageTransHuge(page)) { - index += HPAGE_PMD_NR - 1; - i += HPAGE_PMD_NR - 1; - /* 'end' is in the middle of THP */ - if (index == round_down(end, HPAGE_PMD_NR)) - continue; } ret = invalidate_inode_page(page); @@ -547,9 +544,9 @@ unsigned long invalidate_mapping_pages(struct address_space *mapping, count += ret; } pagevec_remove_exceptionals(&pvec); + index += pvec.nr ? hpage_nr_pages(pvec.pages[pvec.nr - 1]) : 1; pagevec_release(&pvec); cond_resched(); - index++; } return count; } -- 2.11.0 -- To unsubscribe from this list: send the line "unsubscribe linux-block" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html