From b93b016313b3ba8003c3b8bb71f569af91f19fc7 Mon Sep 17 00:00:00 2001 From: Matthew Wilcox Date: Tue, 10 Apr 2018 16:36:56 -0700 Subject: page cache: use xa_lock Remove the address_space ->tree_lock and use the xa_lock newly added to the radix_tree_root. Rename the address_space ->page_tree to ->i_pages, since we don't really care that it's a tree. [willy@infradead.org: fix nds32, fs/dax.c] Link: http://lkml.kernel.org/r/20180406145415.GB20605@bombadil.infradead.orgLink: http://lkml.kernel.org/r/20180313132639.17387-9-willy@infradead.org Signed-off-by: Matthew Wilcox Acked-by: Jeff Layton Cc: Darrick J. Wong Cc: Dave Chinner Cc: Ryusuke Konishi Cc: Will Deacon Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/filemap.c | 84 +++++++++++++++++++++++++++++------------------------------- 1 file changed, 41 insertions(+), 43 deletions(-) (limited to 'mm/filemap.c') diff --git a/mm/filemap.c b/mm/filemap.c index 693f62212a59..ab77e19ab09c 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -66,7 +66,7 @@ * ->i_mmap_rwsem (truncate_pagecache) * ->private_lock (__free_pte->__set_page_dirty_buffers) * ->swap_lock (exclusive_swap_page, others) - * ->mapping->tree_lock + * ->i_pages lock * * ->i_mutex * ->i_mmap_rwsem (truncate->unmap_mapping_range) @@ -74,7 +74,7 @@ * ->mmap_sem * ->i_mmap_rwsem * ->page_table_lock or pte_lock (various, mainly in memory.c) - * ->mapping->tree_lock (arch-dependent flush_dcache_mmap_lock) + * ->i_pages lock (arch-dependent flush_dcache_mmap_lock) * * ->mmap_sem * ->lock_page (access_process_vm) @@ -84,7 +84,7 @@ * * bdi->wb.list_lock * sb_lock (fs/fs-writeback.c) - * ->mapping->tree_lock (__sync_single_inode) + * ->i_pages lock (__sync_single_inode) * * ->i_mmap_rwsem * ->anon_vma.lock (vma_adjust) @@ -95,11 +95,11 @@ * ->page_table_lock or pte_lock * ->swap_lock (try_to_unmap_one) * ->private_lock (try_to_unmap_one) - * ->tree_lock (try_to_unmap_one) + * ->i_pages lock (try_to_unmap_one) * ->zone_lru_lock(zone) (follow_page->mark_page_accessed) * ->zone_lru_lock(zone) (check_pte_range->isolate_lru_page) * ->private_lock (page_remove_rmap->set_page_dirty) - * ->tree_lock (page_remove_rmap->set_page_dirty) + * ->i_pages lock (page_remove_rmap->set_page_dirty) * bdi.wb->list_lock (page_remove_rmap->set_page_dirty) * ->inode->i_lock (page_remove_rmap->set_page_dirty) * ->memcg->move_lock (page_remove_rmap->lock_page_memcg) @@ -118,14 +118,15 @@ static int page_cache_tree_insert(struct address_space *mapping, void **slot; int error; - error = __radix_tree_create(&mapping->page_tree, page->index, 0, + error = __radix_tree_create(&mapping->i_pages, page->index, 0, &node, &slot); if (error) return error; if (*slot) { void *p; - p = radix_tree_deref_slot_protected(slot, &mapping->tree_lock); + p = radix_tree_deref_slot_protected(slot, + &mapping->i_pages.xa_lock); if (!radix_tree_exceptional_entry(p)) return -EEXIST; @@ -133,7 +134,7 @@ static int page_cache_tree_insert(struct address_space *mapping, if (shadowp) *shadowp = p; } - __radix_tree_replace(&mapping->page_tree, node, slot, page, + __radix_tree_replace(&mapping->i_pages, node, slot, page, workingset_lookup_update(mapping)); mapping->nrpages++; return 0; @@ -155,13 +156,13 @@ static void page_cache_tree_delete(struct address_space *mapping, struct radix_tree_node *node; void **slot; - __radix_tree_lookup(&mapping->page_tree, page->index + i, + __radix_tree_lookup(&mapping->i_pages, 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, + radix_tree_clear_tags(&mapping->i_pages, node, slot); + __radix_tree_replace(&mapping->i_pages, node, slot, shadow, workingset_lookup_update(mapping)); } @@ -253,7 +254,7 @@ static void unaccount_page_cache_page(struct address_space *mapping, /* * Delete a page from the page cache and free it. Caller has to make * sure the page is locked and that nobody else uses it - or that usage - * is safe. The caller must hold the mapping's tree_lock. + * is safe. The caller must hold the i_pages lock. */ void __delete_from_page_cache(struct page *page, void *shadow) { @@ -296,9 +297,9 @@ void delete_from_page_cache(struct page *page) unsigned long flags; BUG_ON(!PageLocked(page)); - spin_lock_irqsave(&mapping->tree_lock, flags); + xa_lock_irqsave(&mapping->i_pages, flags); __delete_from_page_cache(page, NULL); - spin_unlock_irqrestore(&mapping->tree_lock, flags); + xa_unlock_irqrestore(&mapping->i_pages, flags); page_cache_free_page(mapping, page); } @@ -309,14 +310,14 @@ EXPORT_SYMBOL(delete_from_page_cache); * @mapping: the mapping to which pages belong * @pvec: pagevec with pages to delete * - * The function walks over mapping->page_tree and removes pages passed in @pvec - * from the radix tree. The function expects @pvec to be sorted by page index. - * It tolerates holes in @pvec (radix tree entries at those indices are not + * The function walks over mapping->i_pages and removes pages passed in @pvec + * from the mapping. The function expects @pvec to be sorted by page index. + * It tolerates holes in @pvec (mapping entries at those indices are not * modified). The function expects only THP head pages to be present in the - * @pvec and takes care to delete all corresponding tail pages from the radix - * tree as well. + * @pvec and takes care to delete all corresponding tail pages from the + * mapping as well. * - * The function expects mapping->tree_lock to be held. + * The function expects the i_pages lock to be held. */ static void page_cache_tree_delete_batch(struct address_space *mapping, @@ -330,11 +331,11 @@ page_cache_tree_delete_batch(struct address_space *mapping, pgoff_t start; start = pvec->pages[0]->index; - radix_tree_for_each_slot(slot, &mapping->page_tree, &iter, start) { + radix_tree_for_each_slot(slot, &mapping->i_pages, &iter, start) { if (i >= pagevec_count(pvec) && !tail_pages) break; page = radix_tree_deref_slot_protected(slot, - &mapping->tree_lock); + &mapping->i_pages.xa_lock); if (radix_tree_exceptional_entry(page)) continue; if (!tail_pages) { @@ -357,8 +358,8 @@ page_cache_tree_delete_batch(struct address_space *mapping, } else { tail_pages--; } - radix_tree_clear_tags(&mapping->page_tree, iter.node, slot); - __radix_tree_replace(&mapping->page_tree, iter.node, slot, NULL, + radix_tree_clear_tags(&mapping->i_pages, iter.node, slot); + __radix_tree_replace(&mapping->i_pages, iter.node, slot, NULL, workingset_lookup_update(mapping)); total_pages++; } @@ -374,14 +375,14 @@ void delete_from_page_cache_batch(struct address_space *mapping, if (!pagevec_count(pvec)) return; - spin_lock_irqsave(&mapping->tree_lock, flags); + xa_lock_irqsave(&mapping->i_pages, flags); for (i = 0; i < pagevec_count(pvec); i++) { trace_mm_filemap_delete_from_page_cache(pvec->pages[i]); unaccount_page_cache_page(mapping, pvec->pages[i]); } page_cache_tree_delete_batch(mapping, pvec); - spin_unlock_irqrestore(&mapping->tree_lock, flags); + xa_unlock_irqrestore(&mapping->i_pages, flags); for (i = 0; i < pagevec_count(pvec); i++) page_cache_free_page(mapping, pvec->pages[i]); @@ -798,7 +799,7 @@ int replace_page_cache_page(struct page *old, struct page *new, gfp_t gfp_mask) new->mapping = mapping; new->index = offset; - spin_lock_irqsave(&mapping->tree_lock, flags); + xa_lock_irqsave(&mapping->i_pages, flags); __delete_from_page_cache(old, NULL); error = page_cache_tree_insert(mapping, new, NULL); BUG_ON(error); @@ -810,7 +811,7 @@ int replace_page_cache_page(struct page *old, struct page *new, gfp_t gfp_mask) __inc_node_page_state(new, NR_FILE_PAGES); if (PageSwapBacked(new)) __inc_node_page_state(new, NR_SHMEM); - spin_unlock_irqrestore(&mapping->tree_lock, flags); + xa_unlock_irqrestore(&mapping->i_pages, flags); mem_cgroup_migrate(old, new); radix_tree_preload_end(); if (freepage) @@ -852,7 +853,7 @@ static int __add_to_page_cache_locked(struct page *page, page->mapping = mapping; page->index = offset; - spin_lock_irq(&mapping->tree_lock); + xa_lock_irq(&mapping->i_pages); error = page_cache_tree_insert(mapping, page, shadowp); radix_tree_preload_end(); if (unlikely(error)) @@ -861,7 +862,7 @@ static int __add_to_page_cache_locked(struct page *page, /* hugetlb pages do not participate in page cache accounting. */ if (!huge) __inc_node_page_state(page, NR_FILE_PAGES); - spin_unlock_irq(&mapping->tree_lock); + xa_unlock_irq(&mapping->i_pages); if (!huge) mem_cgroup_commit_charge(page, memcg, false, false); trace_mm_filemap_add_to_page_cache(page); @@ -869,7 +870,7 @@ static int __add_to_page_cache_locked(struct page *page, err_insert: page->mapping = NULL; /* Leave page->index set: truncation relies upon it */ - spin_unlock_irq(&mapping->tree_lock); + xa_unlock_irq(&mapping->i_pages); if (!huge) mem_cgroup_cancel_charge(page, memcg, false); put_page(page); @@ -1353,7 +1354,7 @@ pgoff_t page_cache_next_hole(struct address_space *mapping, for (i = 0; i < max_scan; i++) { struct page *page; - page = radix_tree_lookup(&mapping->page_tree, index); + page = radix_tree_lookup(&mapping->i_pages, index); if (!page || radix_tree_exceptional_entry(page)) break; index++; @@ -1394,7 +1395,7 @@ pgoff_t page_cache_prev_hole(struct address_space *mapping, for (i = 0; i < max_scan; i++) { struct page *page; - page = radix_tree_lookup(&mapping->page_tree, index); + page = radix_tree_lookup(&mapping->i_pages, index); if (!page || radix_tree_exceptional_entry(page)) break; index--; @@ -1427,7 +1428,7 @@ struct page *find_get_entry(struct address_space *mapping, pgoff_t offset) rcu_read_lock(); repeat: page = NULL; - pagep = radix_tree_lookup_slot(&mapping->page_tree, offset); + pagep = radix_tree_lookup_slot(&mapping->i_pages, offset); if (pagep) { page = radix_tree_deref_slot(pagep); if (unlikely(!page)) @@ -1633,7 +1634,7 @@ unsigned find_get_entries(struct address_space *mapping, return 0; rcu_read_lock(); - radix_tree_for_each_slot(slot, &mapping->page_tree, &iter, start) { + radix_tree_for_each_slot(slot, &mapping->i_pages, &iter, start) { struct page *head, *page; repeat: page = radix_tree_deref_slot(slot); @@ -1710,7 +1711,7 @@ unsigned find_get_pages_range(struct address_space *mapping, pgoff_t *start, return 0; rcu_read_lock(); - radix_tree_for_each_slot(slot, &mapping->page_tree, &iter, *start) { + radix_tree_for_each_slot(slot, &mapping->i_pages, &iter, *start) { struct page *head, *page; if (iter.index > end) @@ -1795,7 +1796,7 @@ unsigned find_get_pages_contig(struct address_space *mapping, pgoff_t index, return 0; rcu_read_lock(); - radix_tree_for_each_contig(slot, &mapping->page_tree, &iter, index) { + radix_tree_for_each_contig(slot, &mapping->i_pages, &iter, index) { struct page *head, *page; repeat: page = radix_tree_deref_slot(slot); @@ -1875,8 +1876,7 @@ unsigned find_get_pages_range_tag(struct address_space *mapping, pgoff_t *index, return 0; rcu_read_lock(); - radix_tree_for_each_tagged(slot, &mapping->page_tree, - &iter, *index, tag) { + radix_tree_for_each_tagged(slot, &mapping->i_pages, &iter, *index, tag) { struct page *head, *page; if (iter.index > end) @@ -1969,8 +1969,7 @@ unsigned find_get_entries_tag(struct address_space *mapping, pgoff_t start, return 0; rcu_read_lock(); - radix_tree_for_each_tagged(slot, &mapping->page_tree, - &iter, start, tag) { + radix_tree_for_each_tagged(slot, &mapping->i_pages, &iter, start, tag) { struct page *head, *page; repeat: page = radix_tree_deref_slot(slot); @@ -2624,8 +2623,7 @@ void filemap_map_pages(struct vm_fault *vmf, struct page *head, *page; rcu_read_lock(); - radix_tree_for_each_slot(slot, &mapping->page_tree, &iter, - start_pgoff) { + radix_tree_for_each_slot(slot, &mapping->i_pages, &iter, start_pgoff) { if (iter.index > end_pgoff) break; repeat: -- cgit v1.2.3