Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/tools/testing/radix-tree/multiorder.c b/tools/testing/radix-tree/multiorder.c
index 7bf4056..9eae0fb 100644
--- a/tools/testing/radix-tree/multiorder.c
+++ b/tools/testing/radix-tree/multiorder.c
@@ -1,17 +1,9 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * multiorder.c: Multi-order radix tree entry testing
  * Copyright (c) 2016 Intel Corporation
  * Author: Ross Zwisler <ross.zwisler@linux.intel.com>
  * Author: Matthew Wilcox <matthew.r.wilcox@intel.com>
- *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms and conditions of the GNU General Public License,
- * version 2, as published by the Free Software Foundation.
- *
- * This program is distributed in the hope it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
- * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
- * more details.
  */
 #include <linux/radix-tree.h>
 #include <linux/slab.h>
@@ -20,230 +12,39 @@
 
 #include "test.h"
 
-#define for_each_index(i, base, order) \
-	for (i = base; i < base + (1 << order); i++)
-
-static void __multiorder_tag_test(int index, int order)
+static int item_insert_order(struct xarray *xa, unsigned long index,
+			unsigned order)
 {
-	RADIX_TREE(tree, GFP_KERNEL);
-	int base, err, i;
+	XA_STATE_ORDER(xas, xa, index, order);
+	struct item *item = item_create(index, order);
 
-	/* our canonical entry */
-	base = index & ~((1 << order) - 1);
+	do {
+		xas_lock(&xas);
+		xas_store(&xas, item);
+		xas_unlock(&xas);
+	} while (xas_nomem(&xas, GFP_KERNEL));
 
-	printv(2, "Multiorder tag test with index %d, canonical entry %d\n",
-			index, base);
+	if (!xas_error(&xas))
+		return 0;
 
-	err = item_insert_order(&tree, index, order);
-	assert(!err);
-
-	/*
-	 * Verify we get collisions for covered indices.  We try and fail to
-	 * insert an exceptional entry so we don't leak memory via
-	 * item_insert_order().
-	 */
-	for_each_index(i, base, order) {
-		err = __radix_tree_insert(&tree, i, order,
-				(void *)(0xA0 | RADIX_TREE_EXCEPTIONAL_ENTRY));
-		assert(err == -EEXIST);
-	}
-
-	for_each_index(i, base, order) {
-		assert(!radix_tree_tag_get(&tree, i, 0));
-		assert(!radix_tree_tag_get(&tree, i, 1));
-	}
-
-	assert(radix_tree_tag_set(&tree, index, 0));
-
-	for_each_index(i, base, order) {
-		assert(radix_tree_tag_get(&tree, i, 0));
-		assert(!radix_tree_tag_get(&tree, i, 1));
-	}
-
-	assert(tag_tagged_items(&tree, NULL, 0, ~0UL, 10, 0, 1) == 1);
-	assert(radix_tree_tag_clear(&tree, index, 0));
-
-	for_each_index(i, base, order) {
-		assert(!radix_tree_tag_get(&tree, i, 0));
-		assert(radix_tree_tag_get(&tree, i, 1));
-	}
-
-	assert(radix_tree_tag_clear(&tree, index, 1));
-
-	assert(!radix_tree_tagged(&tree, 0));
-	assert(!radix_tree_tagged(&tree, 1));
-
-	item_kill_tree(&tree);
+	free(item);
+	return xas_error(&xas);
 }
 
-static void __multiorder_tag_test2(unsigned order, unsigned long index2)
+void multiorder_iteration(struct xarray *xa)
 {
-	RADIX_TREE(tree, GFP_KERNEL);
-	unsigned long index = (1 << order);
-	index2 += index;
-
-	assert(item_insert_order(&tree, 0, order) == 0);
-	assert(item_insert(&tree, index2) == 0);
-
-	assert(radix_tree_tag_set(&tree, 0, 0));
-	assert(radix_tree_tag_set(&tree, index2, 0));
-
-	assert(tag_tagged_items(&tree, NULL, 0, ~0UL, 10, 0, 1) == 2);
-
-	item_kill_tree(&tree);
-}
-
-static void multiorder_tag_tests(void)
-{
-	int i, j;
-
-	/* test multi-order entry for indices 0-7 with no sibling pointers */
-	__multiorder_tag_test(0, 3);
-	__multiorder_tag_test(5, 3);
-
-	/* test multi-order entry for indices 8-15 with no sibling pointers */
-	__multiorder_tag_test(8, 3);
-	__multiorder_tag_test(15, 3);
-
-	/*
-	 * Our order 5 entry covers indices 0-31 in a tree with height=2.
-	 * This is broken up as follows:
-	 * 0-7:		canonical entry
-	 * 8-15:	sibling 1
-	 * 16-23:	sibling 2
-	 * 24-31:	sibling 3
-	 */
-	__multiorder_tag_test(0, 5);
-	__multiorder_tag_test(29, 5);
-
-	/* same test, but with indices 32-63 */
-	__multiorder_tag_test(32, 5);
-	__multiorder_tag_test(44, 5);
-
-	/*
-	 * Our order 8 entry covers indices 0-255 in a tree with height=3.
-	 * This is broken up as follows:
-	 * 0-63:	canonical entry
-	 * 64-127:	sibling 1
-	 * 128-191:	sibling 2
-	 * 192-255:	sibling 3
-	 */
-	__multiorder_tag_test(0, 8);
-	__multiorder_tag_test(190, 8);
-
-	/* same test, but with indices 256-511 */
-	__multiorder_tag_test(256, 8);
-	__multiorder_tag_test(300, 8);
-
-	__multiorder_tag_test(0x12345678UL, 8);
-
-	for (i = 1; i < 10; i++)
-		for (j = 0; j < (10 << i); j++)
-			__multiorder_tag_test2(i, j);
-}
-
-static void multiorder_check(unsigned long index, int order)
-{
-	unsigned long i;
-	unsigned long min = index & ~((1UL << order) - 1);
-	unsigned long max = min + (1UL << order);
-	void **slot;
-	struct item *item2 = item_create(min, order);
-	RADIX_TREE(tree, GFP_KERNEL);
-
-	printv(2, "Multiorder index %ld, order %d\n", index, order);
-
-	assert(item_insert_order(&tree, index, order) == 0);
-
-	for (i = min; i < max; i++) {
-		struct item *item = item_lookup(&tree, i);
-		assert(item != 0);
-		assert(item->index == index);
-	}
-	for (i = 0; i < min; i++)
-		item_check_absent(&tree, i);
-	for (i = max; i < 2*max; i++)
-		item_check_absent(&tree, i);
-	for (i = min; i < max; i++)
-		assert(radix_tree_insert(&tree, i, item2) == -EEXIST);
-
-	slot = radix_tree_lookup_slot(&tree, index);
-	free(*slot);
-	radix_tree_replace_slot(&tree, slot, item2);
-	for (i = min; i < max; i++) {
-		struct item *item = item_lookup(&tree, i);
-		assert(item != 0);
-		assert(item->index == min);
-	}
-
-	assert(item_delete(&tree, min) != 0);
-
-	for (i = 0; i < 2*max; i++)
-		item_check_absent(&tree, i);
-}
-
-static void multiorder_shrink(unsigned long index, int order)
-{
-	unsigned long i;
-	unsigned long max = 1 << order;
-	RADIX_TREE(tree, GFP_KERNEL);
-	struct radix_tree_node *node;
-
-	printv(2, "Multiorder shrink index %ld, order %d\n", index, order);
-
-	assert(item_insert_order(&tree, 0, order) == 0);
-
-	node = tree.rnode;
-
-	assert(item_insert(&tree, index) == 0);
-	assert(node != tree.rnode);
-
-	assert(item_delete(&tree, index) != 0);
-	assert(node == tree.rnode);
-
-	for (i = 0; i < max; i++) {
-		struct item *item = item_lookup(&tree, i);
-		assert(item != 0);
-		assert(item->index == 0);
-	}
-	for (i = max; i < 2*max; i++)
-		item_check_absent(&tree, i);
-
-	if (!item_delete(&tree, 0)) {
-		printv(2, "failed to delete index %ld (order %d)\n", index, order);
-		abort();
-	}
-
-	for (i = 0; i < 2*max; i++)
-		item_check_absent(&tree, i);
-}
-
-static void multiorder_insert_bug(void)
-{
-	RADIX_TREE(tree, GFP_KERNEL);
-
-	item_insert(&tree, 0);
-	radix_tree_tag_set(&tree, 0, 0);
-	item_insert_order(&tree, 3 << 6, 6);
-
-	item_kill_tree(&tree);
-}
-
-void multiorder_iteration(void)
-{
-	RADIX_TREE(tree, GFP_KERNEL);
-	struct radix_tree_iter iter;
-	void **slot;
+	XA_STATE(xas, xa, 0);
+	struct item *item;
 	int i, j, err;
 
-	printv(1, "Multiorder iteration test\n");
-
 #define NUM_ENTRIES 11
 	int index[NUM_ENTRIES] = {0, 2, 4, 8, 16, 32, 34, 36, 64, 72, 128};
 	int order[NUM_ENTRIES] = {1, 1, 2, 3,  4,  1,  0,  1,  3,  0, 7};
 
+	printv(1, "Multiorder iteration test\n");
+
 	for (i = 0; i < NUM_ENTRIES; i++) {
-		err = item_insert_order(&tree, index[i], order[i]);
+		err = item_insert_order(xa, index[i], order[i]);
 		assert(!err);
 	}
 
@@ -252,14 +53,14 @@
 			if (j <= (index[i] | ((1 << order[i]) - 1)))
 				break;
 
-		radix_tree_for_each_slot(slot, &tree, &iter, j) {
-			int height = order[i] / RADIX_TREE_MAP_SHIFT;
-			int shift = height * RADIX_TREE_MAP_SHIFT;
+		xas_set(&xas, j);
+		xas_for_each(&xas, item, ULONG_MAX) {
+			int height = order[i] / XA_CHUNK_SHIFT;
+			int shift = height * XA_CHUNK_SHIFT;
 			unsigned long mask = (1UL << order[i]) - 1;
-			struct item *item = *slot;
 
-			assert((iter.index | mask) == (index[i] | mask));
-			assert(iter.shift == shift);
+			assert((xas.xa_index | mask) == (index[i] | mask));
+			assert(xas.xa_node->shift == shift);
 			assert(!radix_tree_is_internal_node(item));
 			assert((item->index | mask) == (index[i] | mask));
 			assert(item->order == order[i]);
@@ -267,18 +68,15 @@
 		}
 	}
 
-	item_kill_tree(&tree);
+	item_kill_tree(xa);
 }
 
-void multiorder_tagged_iteration(void)
+void multiorder_tagged_iteration(struct xarray *xa)
 {
-	RADIX_TREE(tree, GFP_KERNEL);
-	struct radix_tree_iter iter;
-	void **slot;
+	XA_STATE(xas, xa, 0);
+	struct item *item;
 	int i, j;
 
-	printv(1, "Multiorder tagged iteration test\n");
-
 #define MT_NUM_ENTRIES 9
 	int index[MT_NUM_ENTRIES] = {0, 2, 4, 16, 32, 40, 64, 72, 128};
 	int order[MT_NUM_ENTRIES] = {1, 0, 2, 4,  3,  1,  3,  0,   7};
@@ -286,13 +84,15 @@
 #define TAG_ENTRIES 7
 	int tag_index[TAG_ENTRIES] = {0, 4, 16, 40, 64, 72, 128};
 
-	for (i = 0; i < MT_NUM_ENTRIES; i++)
-		assert(!item_insert_order(&tree, index[i], order[i]));
+	printv(1, "Multiorder tagged iteration test\n");
 
-	assert(!radix_tree_tagged(&tree, 1));
+	for (i = 0; i < MT_NUM_ENTRIES; i++)
+		assert(!item_insert_order(xa, index[i], order[i]));
+
+	assert(!xa_marked(xa, XA_MARK_1));
 
 	for (i = 0; i < TAG_ENTRIES; i++)
-		assert(radix_tree_tag_set(&tree, tag_index[i], 1));
+		xa_set_mark(xa, tag_index[i], XA_MARK_1);
 
 	for (j = 0; j < 256; j++) {
 		int k;
@@ -304,23 +104,23 @@
 				break;
 		}
 
-		radix_tree_for_each_tagged(slot, &tree, &iter, j, 1) {
+		xas_set(&xas, j);
+		xas_for_each_marked(&xas, item, ULONG_MAX, XA_MARK_1) {
 			unsigned long mask;
-			struct item *item = *slot;
 			for (k = i; index[k] < tag_index[i]; k++)
 				;
 			mask = (1UL << order[k]) - 1;
 
-			assert((iter.index | mask) == (tag_index[i] | mask));
-			assert(!radix_tree_is_internal_node(item));
+			assert((xas.xa_index | mask) == (tag_index[i] | mask));
+			assert(!xa_is_internal(item));
 			assert((item->index | mask) == (tag_index[i] | mask));
 			assert(item->order == order[k]);
 			i++;
 		}
 	}
 
-	assert(tag_tagged_items(&tree, NULL, 0, ~0UL, TAG_ENTRIES, 1, 2) ==
-				TAG_ENTRIES);
+	assert(tag_tagged_items(xa, 0, ULONG_MAX, TAG_ENTRIES, XA_MARK_1,
+				XA_MARK_2) == TAG_ENTRIES);
 
 	for (j = 0; j < 256; j++) {
 		int mask, k;
@@ -332,297 +132,31 @@
 				break;
 		}
 
-		radix_tree_for_each_tagged(slot, &tree, &iter, j, 2) {
-			struct item *item = *slot;
+		xas_set(&xas, j);
+		xas_for_each_marked(&xas, item, ULONG_MAX, XA_MARK_2) {
 			for (k = i; index[k] < tag_index[i]; k++)
 				;
 			mask = (1 << order[k]) - 1;
 
-			assert((iter.index | mask) == (tag_index[i] | mask));
-			assert(!radix_tree_is_internal_node(item));
+			assert((xas.xa_index | mask) == (tag_index[i] | mask));
+			assert(!xa_is_internal(item));
 			assert((item->index | mask) == (tag_index[i] | mask));
 			assert(item->order == order[k]);
 			i++;
 		}
 	}
 
-	assert(tag_tagged_items(&tree, NULL, 1, ~0UL, MT_NUM_ENTRIES * 2, 1, 0)
-			== TAG_ENTRIES);
+	assert(tag_tagged_items(xa, 1, ULONG_MAX, MT_NUM_ENTRIES * 2, XA_MARK_1,
+				XA_MARK_0) == TAG_ENTRIES);
 	i = 0;
-	radix_tree_for_each_tagged(slot, &tree, &iter, 0, 0) {
-		assert(iter.index == tag_index[i]);
+	xas_set(&xas, 0);
+	xas_for_each_marked(&xas, item, ULONG_MAX, XA_MARK_0) {
+		assert(xas.xa_index == tag_index[i]);
 		i++;
 	}
+	assert(i == TAG_ENTRIES);
 
-	item_kill_tree(&tree);
-}
-
-/*
- * Basic join checks: make sure we can't find an entry in the tree after
- * a larger entry has replaced it
- */
-static void multiorder_join1(unsigned long index,
-				unsigned order1, unsigned order2)
-{
-	unsigned long loc;
-	void *item, *item2 = item_create(index + 1, order1);
-	RADIX_TREE(tree, GFP_KERNEL);
-
-	item_insert_order(&tree, index, order2);
-	item = radix_tree_lookup(&tree, index);
-	radix_tree_join(&tree, index + 1, order1, item2);
-	loc = find_item(&tree, item);
-	if (loc == -1)
-		free(item);
-	item = radix_tree_lookup(&tree, index + 1);
-	assert(item == item2);
-	item_kill_tree(&tree);
-}
-
-/*
- * Check that the accounting of exceptional entries is handled correctly
- * by joining an exceptional entry to a normal pointer.
- */
-static void multiorder_join2(unsigned order1, unsigned order2)
-{
-	RADIX_TREE(tree, GFP_KERNEL);
-	struct radix_tree_node *node;
-	void *item1 = item_create(0, order1);
-	void *item2;
-
-	item_insert_order(&tree, 0, order2);
-	radix_tree_insert(&tree, 1 << order2, (void *)0x12UL);
-	item2 = __radix_tree_lookup(&tree, 1 << order2, &node, NULL);
-	assert(item2 == (void *)0x12UL);
-	assert(node->exceptional == 1);
-
-	item2 = radix_tree_lookup(&tree, 0);
-	free(item2);
-
-	radix_tree_join(&tree, 0, order1, item1);
-	item2 = __radix_tree_lookup(&tree, 1 << order2, &node, NULL);
-	assert(item2 == item1);
-	assert(node->exceptional == 0);
-	item_kill_tree(&tree);
-}
-
-/*
- * This test revealed an accounting bug for exceptional entries at one point.
- * Nodes were being freed back into the pool with an elevated exception count
- * by radix_tree_join() and then radix_tree_split() was failing to zero the
- * count of exceptional entries.
- */
-static void multiorder_join3(unsigned int order)
-{
-	RADIX_TREE(tree, GFP_KERNEL);
-	struct radix_tree_node *node;
-	void **slot;
-	struct radix_tree_iter iter;
-	unsigned long i;
-
-	for (i = 0; i < (1 << order); i++) {
-		radix_tree_insert(&tree, i, (void *)0x12UL);
-	}
-
-	radix_tree_join(&tree, 0, order, (void *)0x16UL);
-	rcu_barrier();
-
-	radix_tree_split(&tree, 0, 0);
-
-	radix_tree_for_each_slot(slot, &tree, &iter, 0) {
-		radix_tree_iter_replace(&tree, &iter, slot, (void *)0x12UL);
-	}
-
-	__radix_tree_lookup(&tree, 0, &node, NULL);
-	assert(node->exceptional == node->count);
-
-	item_kill_tree(&tree);
-}
-
-static void multiorder_join(void)
-{
-	int i, j, idx;
-
-	for (idx = 0; idx < 1024; idx = idx * 2 + 3) {
-		for (i = 1; i < 15; i++) {
-			for (j = 0; j < i; j++) {
-				multiorder_join1(idx, i, j);
-			}
-		}
-	}
-
-	for (i = 1; i < 15; i++) {
-		for (j = 0; j < i; j++) {
-			multiorder_join2(i, j);
-		}
-	}
-
-	for (i = 3; i < 10; i++) {
-		multiorder_join3(i);
-	}
-}
-
-static void check_mem(unsigned old_order, unsigned new_order, unsigned alloc)
-{
-	struct radix_tree_preload *rtp = &radix_tree_preloads;
-	if (rtp->nr != 0)
-		printv(2, "split(%u %u) remaining %u\n", old_order, new_order,
-							rtp->nr);
-	/*
-	 * Can't check for equality here as some nodes may have been
-	 * RCU-freed while we ran.  But we should never finish with more
-	 * nodes allocated since they should have all been preloaded.
-	 */
-	if (nr_allocated > alloc)
-		printv(2, "split(%u %u) allocated %u %u\n", old_order, new_order,
-							alloc, nr_allocated);
-}
-
-static void __multiorder_split(int old_order, int new_order)
-{
-	RADIX_TREE(tree, GFP_ATOMIC);
-	void **slot;
-	struct radix_tree_iter iter;
-	unsigned alloc;
-	struct item *item;
-
-	radix_tree_preload(GFP_KERNEL);
-	assert(item_insert_order(&tree, 0, old_order) == 0);
-	radix_tree_preload_end();
-
-	/* Wipe out the preloaded cache or it'll confuse check_mem() */
-	radix_tree_cpu_dead(0);
-
-	item = radix_tree_tag_set(&tree, 0, 2);
-
-	radix_tree_split_preload(old_order, new_order, GFP_KERNEL);
-	alloc = nr_allocated;
-	radix_tree_split(&tree, 0, new_order);
-	check_mem(old_order, new_order, alloc);
-	radix_tree_for_each_slot(slot, &tree, &iter, 0) {
-		radix_tree_iter_replace(&tree, &iter, slot,
-					item_create(iter.index, new_order));
-	}
-	radix_tree_preload_end();
-
-	item_kill_tree(&tree);
-	free(item);
-}
-
-static void __multiorder_split2(int old_order, int new_order)
-{
-	RADIX_TREE(tree, GFP_KERNEL);
-	void **slot;
-	struct radix_tree_iter iter;
-	struct radix_tree_node *node;
-	void *item;
-
-	__radix_tree_insert(&tree, 0, old_order, (void *)0x12);
-
-	item = __radix_tree_lookup(&tree, 0, &node, NULL);
-	assert(item == (void *)0x12);
-	assert(node->exceptional > 0);
-
-	radix_tree_split(&tree, 0, new_order);
-	radix_tree_for_each_slot(slot, &tree, &iter, 0) {
-		radix_tree_iter_replace(&tree, &iter, slot,
-					item_create(iter.index, new_order));
-	}
-
-	item = __radix_tree_lookup(&tree, 0, &node, NULL);
-	assert(item != (void *)0x12);
-	assert(node->exceptional == 0);
-
-	item_kill_tree(&tree);
-}
-
-static void __multiorder_split3(int old_order, int new_order)
-{
-	RADIX_TREE(tree, GFP_KERNEL);
-	void **slot;
-	struct radix_tree_iter iter;
-	struct radix_tree_node *node;
-	void *item;
-
-	__radix_tree_insert(&tree, 0, old_order, (void *)0x12);
-
-	item = __radix_tree_lookup(&tree, 0, &node, NULL);
-	assert(item == (void *)0x12);
-	assert(node->exceptional > 0);
-
-	radix_tree_split(&tree, 0, new_order);
-	radix_tree_for_each_slot(slot, &tree, &iter, 0) {
-		radix_tree_iter_replace(&tree, &iter, slot, (void *)0x16);
-	}
-
-	item = __radix_tree_lookup(&tree, 0, &node, NULL);
-	assert(item == (void *)0x16);
-	assert(node->exceptional > 0);
-
-	item_kill_tree(&tree);
-
-	__radix_tree_insert(&tree, 0, old_order, (void *)0x12);
-
-	item = __radix_tree_lookup(&tree, 0, &node, NULL);
-	assert(item == (void *)0x12);
-	assert(node->exceptional > 0);
-
-	radix_tree_split(&tree, 0, new_order);
-	radix_tree_for_each_slot(slot, &tree, &iter, 0) {
-		if (iter.index == (1 << new_order))
-			radix_tree_iter_replace(&tree, &iter, slot,
-						(void *)0x16);
-		else
-			radix_tree_iter_replace(&tree, &iter, slot, NULL);
-	}
-
-	item = __radix_tree_lookup(&tree, 1 << new_order, &node, NULL);
-	assert(item == (void *)0x16);
-	assert(node->count == node->exceptional);
-	do {
-		node = node->parent;
-		if (!node)
-			break;
-		assert(node->count == 1);
-		assert(node->exceptional == 0);
-	} while (1);
-
-	item_kill_tree(&tree);
-}
-
-static void multiorder_split(void)
-{
-	int i, j;
-
-	for (i = 3; i < 11; i++)
-		for (j = 0; j < i; j++) {
-			__multiorder_split(i, j);
-			__multiorder_split2(i, j);
-			__multiorder_split3(i, j);
-		}
-}
-
-static void multiorder_account(void)
-{
-	RADIX_TREE(tree, GFP_KERNEL);
-	struct radix_tree_node *node;
-	void **slot;
-
-	item_insert_order(&tree, 0, 5);
-
-	__radix_tree_insert(&tree, 1 << 5, 5, (void *)0x12);
-	__radix_tree_lookup(&tree, 0, &node, NULL);
-	assert(node->count == node->exceptional * 2);
-	radix_tree_delete(&tree, 1 << 5);
-	assert(node->exceptional == 0);
-
-	__radix_tree_insert(&tree, 1 << 5, 5, (void *)0x12);
-	__radix_tree_lookup(&tree, 1 << 5, &node, &slot);
-	assert(node->count == node->exceptional * 2);
-	__radix_tree_replace(&tree, node, slot, NULL, NULL);
-	assert(node->exceptional == 0);
-
-	item_kill_tree(&tree);
+	item_kill_tree(xa);
 }
 
 bool stop_iteration = false;
@@ -645,68 +179,45 @@
 
 static void *iterator_func(void *ptr)
 {
-	struct radix_tree_root *tree = ptr;
-	struct radix_tree_iter iter;
+	XA_STATE(xas, ptr, 0);
 	struct item *item;
-	void **slot;
 
 	while (!stop_iteration) {
 		rcu_read_lock();
-		radix_tree_for_each_slot(slot, tree, &iter, 0) {
-			item = radix_tree_deref_slot(slot);
-
-			if (!item)
+		xas_for_each(&xas, item, ULONG_MAX) {
+			if (xas_retry(&xas, item))
 				continue;
-			if (radix_tree_deref_retry(item)) {
-				slot = radix_tree_iter_retry(&iter);
-				continue;
-			}
 
-			item_sanity(item, iter.index);
+			item_sanity(item, xas.xa_index);
 		}
 		rcu_read_unlock();
 	}
 	return NULL;
 }
 
-static void multiorder_iteration_race(void)
+static void multiorder_iteration_race(struct xarray *xa)
 {
 	const int num_threads = sysconf(_SC_NPROCESSORS_ONLN);
 	pthread_t worker_thread[num_threads];
-	RADIX_TREE(tree, GFP_KERNEL);
 	int i;
 
-	pthread_create(&worker_thread[0], NULL, &creator_func, &tree);
+	pthread_create(&worker_thread[0], NULL, &creator_func, xa);
 	for (i = 1; i < num_threads; i++)
-		pthread_create(&worker_thread[i], NULL, &iterator_func, &tree);
+		pthread_create(&worker_thread[i], NULL, &iterator_func, xa);
 
 	for (i = 0; i < num_threads; i++)
 		pthread_join(worker_thread[i], NULL);
 
-	item_kill_tree(&tree);
+	item_kill_tree(xa);
 }
 
+static DEFINE_XARRAY(array);
+
 void multiorder_checks(void)
 {
-	int i;
-
-	for (i = 0; i < 20; i++) {
-		multiorder_check(200, i);
-		multiorder_check(0, i);
-		multiorder_check((1UL << i) + 1, i);
-	}
-
-	for (i = 0; i < 15; i++)
-		multiorder_shrink((1UL << (i + RADIX_TREE_MAP_SHIFT)), i);
-
-	multiorder_insert_bug();
-	multiorder_tag_tests();
-	multiorder_iteration();
-	multiorder_tagged_iteration();
-	multiorder_join();
-	multiorder_split();
-	multiorder_account();
-	multiorder_iteration_race();
+	multiorder_iteration(&array);
+	multiorder_tagged_iteration(&array);
+	multiorder_iteration_race(&array);
 
 	radix_tree_cpu_dead(0);
 }