From d604c324524bf61c68182bb27db64656a78fe911 Mon Sep 17 00:00:00 2001 From: Matthew Wilcox Date: Fri, 20 May 2016 17:03:45 -0700 Subject: radix-tree: introduce radix_tree_replace_clear_tags() In addition to replacing the entry, we also clear all associated tags. This is really a one-off special for page_cache_tree_delete() which had far too much detailed knowledge about how the radix tree works. For efficiency, factor node_tag_clear() out of radix_tree_tag_clear() It can be used by radix_tree_delete_item() as well as radix_tree_replace_clear_tags(). Signed-off-by: Matthew Wilcox Cc: Konstantin Khlebnikov Cc: Kirill Shutemov Cc: Jan Kara Cc: Neil Brown Cc: Ross Zwisler Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/filemap.c | 23 +++-------------------- 1 file changed, 3 insertions(+), 20 deletions(-) (limited to 'mm/filemap.c') diff --git a/mm/filemap.c b/mm/filemap.c index b418405903bc..9665b1d4f318 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -114,14 +114,11 @@ static void page_cache_tree_delete(struct address_space *mapping, struct page *page, void *shadow) { struct radix_tree_node *node; - unsigned long index; - unsigned int offset; - unsigned int tag; - void **slot; VM_BUG_ON(!PageLocked(page)); - __radix_tree_lookup(&mapping->page_tree, page->index, &node, &slot); + node = radix_tree_replace_clear_tags(&mapping->page_tree, page->index, + shadow); if (shadow) { mapping->nrexceptional++; @@ -135,23 +132,9 @@ static void page_cache_tree_delete(struct address_space *mapping, } mapping->nrpages--; - if (!node) { - /* Clear direct pointer tags in root node */ - mapping->page_tree.gfp_mask &= __GFP_BITS_MASK; - radix_tree_replace_slot(slot, shadow); + if (!node) return; - } - - /* Clear tree tags for the removed page */ - index = page->index; - offset = index & RADIX_TREE_MAP_MASK; - for (tag = 0; tag < RADIX_TREE_MAX_TAGS; tag++) { - if (test_bit(offset, node->tags[tag])) - radix_tree_tag_clear(&mapping->page_tree, index, tag); - } - /* Delete page, swap shadow entry */ - radix_tree_replace_slot(slot, shadow); workingset_node_pages_dec(node); if (shadow) workingset_node_shadows_inc(node); -- cgit