Commit 7ae3424f authored by Matthew Wilcox's avatar Matthew Wilcox
Browse files

shmem: Convert shmem_partial_swap_usage to XArray 



Simpler code because the xarray takes care of things like the limit and
dereferencing the slot.

Signed-off-by: default avatarMatthew Wilcox <willy@infradead.org>
parent c121d3bb

mm/shmem.c

+4 −14
Original line number Diff line number Diff line
@@ -676,29 +676,19 @@ static int shmem_free_swap(struct address_space *mapping, 
unsigned long shmem_partial_swap_usage(struct address_space *mapping,

						pgoff_t start, pgoff_t end)

{

	struct radix_tree_iter iter;

	void __rcu **slot;

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

	struct page *page;

	unsigned long swapped = 0;



	rcu_read_lock();



	radix_tree_for_each_slot(slot, &mapping->i_pages, &iter, start) {

		if (iter.index >= end)

			break;



		page = radix_tree_deref_slot(slot);



		if (radix_tree_deref_retry(page)) {

			slot = radix_tree_iter_retry(&iter);

	xas_for_each(&xas, page, end - 1) {

		if (xas_retry(&xas, page))

			continue;

		}



		if (xa_is_value(page))

			swapped++;



		if (need_resched()) {

			slot = radix_tree_iter_resume(slot, &iter);

			xas_pause(&xas);

			cond_resched_rcu();

		}

	}