From 69b6c1319b6588b65d853055d5336f662f6cb1a2 Mon Sep 17 00:00:00 2001 From: Matthew Wilcox Date: Sat, 25 Nov 2017 22:52:46 -0500 Subject: mm: Convert truncate to XArray This is essentially xa_cmpxchg() with the locking handled above us, and it doesn't have to handle replacing a NULL entry. Signed-off-by: Matthew Wilcox --- mm/truncate.c | 15 ++++++--------- 1 file changed, 6 insertions(+), 9 deletions(-) (limited to 'mm/truncate.c') diff --git a/mm/truncate.c b/mm/truncate.c index ed778555c9f3..45d68e90b703 100644 --- a/mm/truncate.c +++ b/mm/truncate.c @@ -33,15 +33,12 @@ static inline void __clear_shadow_entry(struct address_space *mapping, pgoff_t index, void *entry) { - struct radix_tree_node *node; - void **slot; + XA_STATE(xas, &mapping->i_pages, index); - if (!__radix_tree_lookup(&mapping->i_pages, index, &node, &slot)) + xas_set_update(&xas, workingset_update_node); + if (xas_load(&xas) != entry) return; - if (*slot != entry) - return; - __radix_tree_replace(&mapping->i_pages, node, slot, NULL, - workingset_update_node); + xas_store(&xas, NULL); mapping->nrexceptional--; } @@ -738,10 +735,10 @@ int invalidate_inode_pages2_range(struct address_space *mapping, index++; } /* - * For DAX we invalidate page tables after invalidating radix tree. We + * For DAX we invalidate page tables after invalidating page cache. We * could invalidate page tables while invalidating each entry however * that would be expensive. And doing range unmapping before doesn't - * work as we have no cheap way to find whether radix tree entry didn't + * work as we have no cheap way to find whether page cache entry didn't * get remapped later. */ if (dax_mapping(mapping)) { -- cgit v1.2.3