Commit 04edf02c authored by Matthew Wilcox's avatar Matthew Wilcox
Browse files

fs: Convert writeback to XArray 



A couple of short loops.

Signed-off-by: default avatarMatthew Wilcox <willy@infradead.org>
parent ec82e1c1

fs/fs-writeback.c

+9 −16
Original line number Diff line number Diff line
@@ -339,9 +339,9 @@ static void inode_switch_wbs_work_fn(struct work_struct *work) 
	struct address_space *mapping = inode->i_mapping;

	struct bdi_writeback *old_wb = inode->i_wb;

	struct bdi_writeback *new_wb = isw->new_wb;

	struct radix_tree_iter iter;

	XA_STATE(xas, &mapping->i_pages, 0);

	struct page *page;

	bool switched = false;

	void **slot;



	/*

	 * By the time control reaches here, RCU grace period has passed
@@ -375,26 +375,19 @@ static void inode_switch_wbs_work_fn(struct work_struct *work) 
	 * to possibly dirty pages while PAGECACHE_TAG_WRITEBACK points to

	 * pages actually under writeback.

	 */

	radix_tree_for_each_tagged(slot, &mapping->i_pages, &iter, 0,

				   PAGECACHE_TAG_DIRTY) {

		struct page *page = radix_tree_deref_slot_protected(slot,

						&mapping->i_pages.xa_lock);

		if (likely(page) && PageDirty(page)) {

	xas_for_each_marked(&xas, page, ULONG_MAX, PAGECACHE_TAG_DIRTY) {

		if (PageDirty(page)) {

			dec_wb_stat(old_wb, WB_RECLAIMABLE);

			inc_wb_stat(new_wb, WB_RECLAIMABLE);

		}

	}



	radix_tree_for_each_tagged(slot, &mapping->i_pages, &iter, 0,

				   PAGECACHE_TAG_WRITEBACK) {

		struct page *page = radix_tree_deref_slot_protected(slot,

						&mapping->i_pages.xa_lock);

		if (likely(page)) {

	xas_set(&xas, 0);

	xas_for_each_marked(&xas, page, ULONG_MAX, PAGECACHE_TAG_WRITEBACK) {

		WARN_ON_ONCE(!PageWriteback(page));

		dec_wb_stat(old_wb, WB_WRITEBACK);

		inc_wb_stat(new_wb, WB_WRITEBACK);

	}

	}



	wb_get(new_wb);