From: Matthew Wilcox <[email protected]> Avoids walking the radix tree multiple times looking for tags.
Signed-off-by: Matthew Wilcox <[email protected]> --- fs/dax.c | 17 +++++++++-------- 1 file changed, 9 insertions(+), 8 deletions(-) diff --git a/fs/dax.c b/fs/dax.c index b8ed7bf32ba1..0566a150c458 100644 --- a/fs/dax.c +++ b/fs/dax.c @@ -676,27 +676,28 @@ EXPORT_SYMBOL_GPL(dax_layout_busy_page); static int __dax_invalidate_entry(struct address_space *mapping, pgoff_t index, bool trunc) { + XA_STATE(xas, &mapping->i_pages, index); int ret = 0; void *entry; - struct radix_tree_root *pages = &mapping->i_pages; - xa_lock_irq(pages); - entry = get_unlocked_mapping_entry(mapping, index, NULL); + xas_lock_irq(&xas); + entry = get_unlocked_entry(&xas); if (!entry || WARN_ON_ONCE(!xa_is_value(entry))) goto out; if (!trunc && - (radix_tree_tag_get(pages, index, PAGECACHE_TAG_DIRTY) || - radix_tree_tag_get(pages, index, PAGECACHE_TAG_TOWRITE))) + (xas_get_tag(&xas, PAGECACHE_TAG_DIRTY) || + xas_get_tag(&xas, PAGECACHE_TAG_TOWRITE))) goto out; dax_disassociate_entry(entry, mapping, trunc); - radix_tree_delete(pages, index); + xas_store(&xas, NULL); mapping->nrexceptional--; ret = 1; out: - put_unlocked_mapping_entry(mapping, index, entry); - xa_unlock_irq(pages); + put_unlocked_entry(&xas, entry); + xas_unlock_irq(&xas); return ret; } + /* * Delete DAX entry at @index from @mapping. Wait for it * to be unlocked before deleting it. -- 2.17.1
