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/page-writeback.c | 43 ++++++++++++++++++++----------------------- 1 file changed, 20 insertions(+), 23 deletions(-) (limited to 'mm/page-writeback.c') diff --git a/mm/page-writeback.c b/mm/page-writeback.c index 586f31261c83..5c1a3279e63f 100644 --- a/mm/page-writeback.c +++ b/mm/page-writeback.c @@ -2099,7 +2099,8 @@ void __init page_writeback_init(void) * so that it can tag pages faster than a dirtying process can create them). */ /* - * We tag pages in batches of WRITEBACK_TAG_BATCH to reduce tree_lock latency. + * We tag pages in batches of WRITEBACK_TAG_BATCH to reduce the i_pages lock + * latency. */ void tag_pages_for_writeback(struct address_space *mapping, pgoff_t start, pgoff_t end) @@ -2109,22 +2110,22 @@ void tag_pages_for_writeback(struct address_space *mapping, struct radix_tree_iter iter; void **slot; - spin_lock_irq(&mapping->tree_lock); - radix_tree_for_each_tagged(slot, &mapping->page_tree, &iter, start, + xa_lock_irq(&mapping->i_pages); + radix_tree_for_each_tagged(slot, &mapping->i_pages, &iter, start, PAGECACHE_TAG_DIRTY) { if (iter.index > end) break; - radix_tree_iter_tag_set(&mapping->page_tree, &iter, + radix_tree_iter_tag_set(&mapping->i_pages, &iter, PAGECACHE_TAG_TOWRITE); tagged++; if ((tagged % WRITEBACK_TAG_BATCH) != 0) continue; slot = radix_tree_iter_resume(slot, &iter); - spin_unlock_irq(&mapping->tree_lock); + xa_unlock_irq(&mapping->i_pages); cond_resched(); - spin_lock_irq(&mapping->tree_lock); + xa_lock_irq(&mapping->i_pages); } - spin_unlock_irq(&mapping->tree_lock); + xa_unlock_irq(&mapping->i_pages); } EXPORT_SYMBOL(tag_pages_for_writeback); @@ -2467,13 +2468,13 @@ int __set_page_dirty_nobuffers(struct page *page) return 1; } - spin_lock_irqsave(&mapping->tree_lock, flags); + xa_lock_irqsave(&mapping->i_pages, flags); BUG_ON(page_mapping(page) != mapping); WARN_ON_ONCE(!PagePrivate(page) && !PageUptodate(page)); account_page_dirtied(page, mapping); - radix_tree_tag_set(&mapping->page_tree, page_index(page), + radix_tree_tag_set(&mapping->i_pages, page_index(page), PAGECACHE_TAG_DIRTY); - spin_unlock_irqrestore(&mapping->tree_lock, flags); + xa_unlock_irqrestore(&mapping->i_pages, flags); unlock_page_memcg(page); if (mapping->host) { @@ -2718,11 +2719,10 @@ int test_clear_page_writeback(struct page *page) struct backing_dev_info *bdi = inode_to_bdi(inode); unsigned long flags; - spin_lock_irqsave(&mapping->tree_lock, flags); + xa_lock_irqsave(&mapping->i_pages, flags); ret = TestClearPageWriteback(page); if (ret) { - radix_tree_tag_clear(&mapping->page_tree, - page_index(page), + radix_tree_tag_clear(&mapping->i_pages, page_index(page), PAGECACHE_TAG_WRITEBACK); if (bdi_cap_account_writeback(bdi)) { struct bdi_writeback *wb = inode_to_wb(inode); @@ -2736,7 +2736,7 @@ int test_clear_page_writeback(struct page *page) PAGECACHE_TAG_WRITEBACK)) sb_clear_inode_writeback(mapping->host); - spin_unlock_irqrestore(&mapping->tree_lock, flags); + xa_unlock_irqrestore(&mapping->i_pages, flags); } else { ret = TestClearPageWriteback(page); } @@ -2766,7 +2766,7 @@ int __test_set_page_writeback(struct page *page, bool keep_write) struct backing_dev_info *bdi = inode_to_bdi(inode); unsigned long flags; - spin_lock_irqsave(&mapping->tree_lock, flags); + xa_lock_irqsave(&mapping->i_pages, flags); ret = TestSetPageWriteback(page); if (!ret) { bool on_wblist; @@ -2774,8 +2774,7 @@ int __test_set_page_writeback(struct page *page, bool keep_write) on_wblist = mapping_tagged(mapping, PAGECACHE_TAG_WRITEBACK); - radix_tree_tag_set(&mapping->page_tree, - page_index(page), + radix_tree_tag_set(&mapping->i_pages, page_index(page), PAGECACHE_TAG_WRITEBACK); if (bdi_cap_account_writeback(bdi)) inc_wb_stat(inode_to_wb(inode), WB_WRITEBACK); @@ -2789,14 +2788,12 @@ int __test_set_page_writeback(struct page *page, bool keep_write) sb_mark_inode_writeback(mapping->host); } if (!PageDirty(page)) - radix_tree_tag_clear(&mapping->page_tree, - page_index(page), + radix_tree_tag_clear(&mapping->i_pages, page_index(page), PAGECACHE_TAG_DIRTY); if (!keep_write) - radix_tree_tag_clear(&mapping->page_tree, - page_index(page), + radix_tree_tag_clear(&mapping->i_pages, page_index(page), PAGECACHE_TAG_TOWRITE); - spin_unlock_irqrestore(&mapping->tree_lock, flags); + xa_unlock_irqrestore(&mapping->i_pages, flags); } else { ret = TestSetPageWriteback(page); } @@ -2816,7 +2813,7 @@ EXPORT_SYMBOL(__test_set_page_writeback); */ int mapping_tagged(struct address_space *mapping, int tag) { - return radix_tree_tagged(&mapping->page_tree, tag); + return radix_tree_tagged(&mapping->i_pages, tag); } EXPORT_SYMBOL(mapping_tagged); -- cgit