radix tree test suite: Convert tag_tagged_items to XArray

The tag_tagged_items() function is supposed to test the page-writeback
tagging code.  Since that has been converted to the XArray, there's
not much point in testing the radix tree's tagging code.  This requires
using the pthread mutex embedded in the xarray instead of an external
lock, so remove the pthread mutexes which protect xarrays/radix trees.
Also remove radix_tree_iter_tag_set() as this was the last user.

Signed-off-by: Matthew Wilcox <willy@infradead.org>

10 files changed, 46 insertions, 71 deletions

diff --git a/include/linux/radix-tree.h b/include/linux/radix-tree.h
index 7b009af3bb1e..9a1460488163 100644
--- a/include/linux/radix-tree.h
+++ b/include/linux/radix-tree.h
@@ -264,8 +264,6 @@ void *radix_tree_tag_clear(struct radix_tree_root *,
 			unsigned long index, unsigned int tag);
 int radix_tree_tag_get(const struct radix_tree_root *,
 			unsigned long index, unsigned int tag);
-void radix_tree_iter_tag_set(struct radix_tree_root *,
-		const struct radix_tree_iter *iter, unsigned int tag);
 void radix_tree_iter_tag_clear(struct radix_tree_root *,
 		const struct radix_tree_iter *iter, unsigned int tag);
 unsigned int radix_tree_gang_lookup_tag(const struct radix_tree_root *,
diff --git a/lib/radix-tree.c b/lib/radix-tree.c
index e92f2b6ae9c5..f107dd2698e3 100644
--- a/lib/radix-tree.c
+++ b/lib/radix-tree.c
@@ -1108,18 +1108,6 @@ void *radix_tree_tag_set(struct radix_tree_root *root,
 }
 EXPORT_SYMBOL(radix_tree_tag_set);
 
-/**
- * radix_tree_iter_tag_set - set a tag on the current iterator entry
- * @root:	radix tree root
- * @iter:	iterator state
- * @tag:	tag to set
- */
-void radix_tree_iter_tag_set(struct radix_tree_root *root,
-			const struct radix_tree_iter *iter, unsigned int tag)
-{
-	node_tag_set(root, iter->node, tag, iter_offset(iter));
-}
-
 static void node_tag_clear(struct radix_tree_root *root,
 				struct radix_tree_node *node,
 				unsigned int tag, unsigned int offset)
diff --git a/tools/testing/radix-tree/iteration_check.c b/tools/testing/radix-tree/iteration_check.c
index a92bab513701..d047327bb9ef 100644
--- a/tools/testing/radix-tree/iteration_check.c
+++ b/tools/testing/radix-tree/iteration_check.c
@@ -18,10 +18,9 @@
 
 #define NUM_THREADS	5
 #define MAX_IDX		100
-#define TAG		0
-#define NEW_TAG		1
+#define TAG		XA_MARK_0
+#define NEW_TAG		XA_MARK_1
 
-static pthread_mutex_t tree_lock = PTHREAD_MUTEX_INITIALIZER;
 static pthread_t threads[NUM_THREADS];
 static unsigned int seeds[3];
 static RADIX_TREE(tree, GFP_KERNEL);
@@ -38,7 +37,7 @@ static void *add_entries_fn(void *arg)
 		int order;
 
 		for (pgoff = 0; pgoff < MAX_IDX; pgoff++) {
-			pthread_mutex_lock(&tree_lock);
+			xa_lock(&tree);
 			for (order = max_order; order >= 0; order--) {
 				if (item_insert_order(&tree, pgoff, order)
 						== 0) {
@@ -46,7 +45,7 @@ static void *add_entries_fn(void *arg)
 					break;
 				}
 			}
-			pthread_mutex_unlock(&tree_lock);
+			xa_unlock(&tree);
 		}
 	}
 
@@ -150,9 +149,9 @@ static void *remove_entries_fn(void *arg)
 
 		pgoff = rand_r(&seeds[2]) % MAX_IDX;
 
-		pthread_mutex_lock(&tree_lock);
+		xa_lock(&tree);
 		item_delete(&tree, pgoff);
-		pthread_mutex_unlock(&tree_lock);
+		xa_unlock(&tree);
 	}
 
 	rcu_unregister_thread();
@@ -165,8 +164,7 @@ static void *tag_entries_fn(void *arg)
 	rcu_register_thread();
 
 	while (!test_complete) {
-		tag_tagged_items(&tree, &tree_lock, 0, MAX_IDX, 10, TAG,
-					NEW_TAG);
+		tag_tagged_items(&tree, 0, MAX_IDX, 10, TAG, NEW_TAG);
 	}
 	rcu_unregister_thread();
 	return NULL;
diff --git a/tools/testing/radix-tree/main.c b/tools/testing/radix-tree/main.c
index 79589ea570ab..77a44c54998f 100644
--- a/tools/testing/radix-tree/main.c
+++ b/tools/testing/radix-tree/main.c
@@ -214,7 +214,7 @@ void copy_tag_check(void)
 	}
 
 //	printf("\ncopying tags...\n");
-	tagged = tag_tagged_items(&tree, NULL, start, end, ITEMS, 0, 1);
+	tagged = tag_tagged_items(&tree, start, end, ITEMS, XA_MARK_0, XA_MARK_1);
 
 //	printf("checking copied tags\n");
 	assert(tagged == count);
@@ -223,7 +223,7 @@ void copy_tag_check(void)
 	/* Copy tags in several rounds */
 //	printf("\ncopying tags...\n");
 	tmp = rand() % (count / 10 + 2);
-	tagged = tag_tagged_items(&tree, NULL, start, end, tmp, 0, 2);
+	tagged = tag_tagged_items(&tree, start, end, tmp, XA_MARK_0, XA_MARK_2);
 	assert(tagged == count);
 
 //	printf("%lu %lu %lu\n", tagged, tmp, count);
diff --git a/tools/testing/radix-tree/multiorder.c b/tools/testing/radix-tree/multiorder.c
index 221e042d1b89..0436554a099a 100644
--- a/tools/testing/radix-tree/multiorder.c
+++ b/tools/testing/radix-tree/multiorder.c
@@ -59,7 +59,7 @@ static void __multiorder_tag_test(int index, int order)
 		assert(!radix_tree_tag_get(&tree, i, 1));
 	}
 
-	assert(tag_tagged_items(&tree, NULL, 0, ~0UL, 10, 0, 1) == 1);
+	assert(tag_tagged_items(&tree, 0, ~0UL, 10, XA_MARK_0, XA_MARK_1) == 1);
 	assert(radix_tree_tag_clear(&tree, index, 0));
 
 	for_each_index(i, base, order) {
@@ -87,7 +87,7 @@ static void __multiorder_tag_test2(unsigned order, unsigned long index2)
 	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);
+	assert(tag_tagged_items(&tree, 0, ~0UL, 10, XA_MARK_0, XA_MARK_1) == 2);
 
 	item_kill_tree(&tree);
 }
@@ -318,8 +318,8 @@ void multiorder_tagged_iteration(void)
 		}
 	}
 
-	assert(tag_tagged_items(&tree, NULL, 0, ~0UL, TAG_ENTRIES, 1, 2) ==
-				TAG_ENTRIES);
+	assert(tag_tagged_items(&tree, 0, ~0UL, TAG_ENTRIES, XA_MARK_1,
+				XA_MARK_2) == TAG_ENTRIES);
 
 	for (j = 0; j < 256; j++) {
 		int mask, k;
@@ -345,8 +345,8 @@ void multiorder_tagged_iteration(void)
 		}
 	}
 
-	assert(tag_tagged_items(&tree, NULL, 1, ~0UL, MT_NUM_ENTRIES * 2, 1, 0)
-			== TAG_ENTRIES);
+	assert(tag_tagged_items(&tree, 1, ~0UL, 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]);
diff --git a/tools/testing/radix-tree/regression1.c b/tools/testing/radix-tree/regression1.c
index b4a4a7168986..a61c7bcbc72d 100644
--- a/tools/testing/radix-tree/regression1.c
+++ b/tools/testing/radix-tree/regression1.c
@@ -44,7 +44,6 @@
 #include "regression.h"
 
 static RADIX_TREE(mt_tree, GFP_KERNEL);
-static pthread_mutex_t mt_lock = PTHREAD_MUTEX_INITIALIZER;
 
 struct page {
 	pthread_mutex_t lock;
@@ -126,29 +125,29 @@ static void *regression1_fn(void *arg)
 			struct page *p;
 
 			p = page_alloc(0);
-			pthread_mutex_lock(&mt_lock);
+			xa_lock(&mt_tree);
 			radix_tree_insert(&mt_tree, 0, p);
-			pthread_mutex_unlock(&mt_lock);
+			xa_unlock(&mt_tree);
 
 			p = page_alloc(1);
-			pthread_mutex_lock(&mt_lock);
+			xa_lock(&mt_tree);
 			radix_tree_insert(&mt_tree, 1, p);
-			pthread_mutex_unlock(&mt_lock);
+			xa_unlock(&mt_tree);
 
-			pthread_mutex_lock(&mt_lock);
+			xa_lock(&mt_tree);
 			p = radix_tree_delete(&mt_tree, 1);
 			pthread_mutex_lock(&p->lock);
 			p->count--;
 			pthread_mutex_unlock(&p->lock);
-			pthread_mutex_unlock(&mt_lock);
+			xa_unlock(&mt_tree);
 			page_free(p);
 
-			pthread_mutex_lock(&mt_lock);
+			xa_lock(&mt_tree);
 			p = radix_tree_delete(&mt_tree, 0);
 			pthread_mutex_lock(&p->lock);
 			p->count--;
 			pthread_mutex_unlock(&p->lock);
-			pthread_mutex_unlock(&mt_lock);
+			xa_unlock(&mt_tree);
 			page_free(p);
 		}
 	} else {
diff --git a/tools/testing/radix-tree/regression2.c b/tools/testing/radix-tree/regression2.c
index 424b91c77831..f2c7e640a919 100644
--- a/tools/testing/radix-tree/regression2.c
+++ b/tools/testing/radix-tree/regression2.c
@@ -53,9 +53,9 @@
 #include "regression.h"
 #include "test.h"
 
-#define PAGECACHE_TAG_DIRTY     0
-#define PAGECACHE_TAG_WRITEBACK 1
-#define PAGECACHE_TAG_TOWRITE   2
+#define PAGECACHE_TAG_DIRTY     XA_MARK_0
+#define PAGECACHE_TAG_WRITEBACK XA_MARK_1
+#define PAGECACHE_TAG_TOWRITE   XA_MARK_2
 
 static RADIX_TREE(mt_tree, GFP_KERNEL);
 unsigned long page_count = 0;
@@ -92,7 +92,7 @@ void regression2_test(void)
 	/* 1. */
 	start = 0;
 	end = max_slots - 2;
-	tag_tagged_items(&mt_tree, NULL, start, end, 1,
+	tag_tagged_items(&mt_tree, start, end, 1,
 				PAGECACHE_TAG_DIRTY, PAGECACHE_TAG_TOWRITE);
 
 	/* 2. */
diff --git a/tools/testing/radix-tree/tag_check.c b/tools/testing/radix-tree/tag_check.c
index 56a42f1c5ab0..f898957b1a19 100644
--- a/tools/testing/radix-tree/tag_check.c
+++ b/tools/testing/radix-tree/tag_check.c
@@ -24,7 +24,7 @@ __simple_checks(struct radix_tree_root *tree, unsigned long index, int tag)
 	item_tag_set(tree, index, tag);
 	ret = item_tag_get(tree, index, tag);
 	assert(ret != 0);
-	ret = tag_tagged_items(tree, NULL, first, ~0UL, 10, tag, !tag);
+	ret = tag_tagged_items(tree, first, ~0UL, 10, tag, !tag);
 	assert(ret == 1);
 	ret = item_tag_get(tree, index, !tag);
 	assert(ret != 0);
@@ -321,7 +321,7 @@ static void single_check(void)
 	assert(ret == 0);
 	verify_tag_consistency(&tree, 0);
 	verify_tag_consistency(&tree, 1);
-	ret = tag_tagged_items(&tree, NULL, first, 10, 10, 0, 1);
+	ret = tag_tagged_items(&tree, first, 10, 10, XA_MARK_0, XA_MARK_1);
 	assert(ret == 1);
 	ret = radix_tree_gang_lookup_tag(&tree, (void **)items, 0, BATCH, 1);
 	assert(ret == 1);
diff --git a/tools/testing/radix-tree/test.c b/tools/testing/radix-tree/test.c
index 470419bfd49d..d70adcd03d35 100644
--- a/tools/testing/radix-tree/test.c
+++ b/tools/testing/radix-tree/test.c
@@ -176,35 +176,28 @@ void item_full_scan(struct radix_tree_root *root, unsigned long start,
 }
 
 /* Use the same pattern as tag_pages_for_writeback() in mm/page-writeback.c */
-int tag_tagged_items(struct radix_tree_root *root, pthread_mutex_t *lock,
-			unsigned long start, unsigned long end, unsigned batch,
-			unsigned iftag, unsigned thentag)
+int tag_tagged_items(struct xarray *xa, unsigned long start, unsigned long end,
+		unsigned batch, xa_mark_t iftag, xa_mark_t thentag)
 {
-	unsigned long tagged = 0;
-	struct radix_tree_iter iter;
-	void **slot;
+	XA_STATE(xas, xa, start);
+	unsigned int tagged = 0;
+	struct item *item;
 
 	if (batch == 0)
 		batch = 1;
 
-	if (lock)
-		pthread_mutex_lock(lock);
-	radix_tree_for_each_tagged(slot, root, &iter, start, iftag) {
-		if (iter.index > end)
-			break;
-		radix_tree_iter_tag_set(root, &iter, thentag);
-		tagged++;
-		if ((tagged % batch) != 0)
+	xas_lock_irq(&xas);
+	xas_for_each_marked(&xas, item, end, iftag) {
+		xas_set_mark(&xas, thentag);
+		if (++tagged % batch)
 			continue;
-		slot = radix_tree_iter_resume(slot, &iter);
-		if (lock) {
-			pthread_mutex_unlock(lock);
-			rcu_barrier();
-			pthread_mutex_lock(lock);
-		}
+
+		xas_pause(&xas);
+		xas_unlock_irq(&xas);
+		rcu_barrier();
+		xas_lock_irq(&xas);
 	}
-	if (lock)
-		pthread_mutex_unlock(lock);
+	xas_unlock_irq(&xas);
 
 	return tagged;
 }
diff --git a/tools/testing/radix-tree/test.h b/tools/testing/radix-tree/test.h
index 9532c18c6cb1..100e9a456f91 100644
--- a/tools/testing/radix-tree/test.h
+++ b/tools/testing/radix-tree/test.h
@@ -29,9 +29,8 @@ void item_full_scan(struct radix_tree_root *root, unsigned long start,
 			unsigned long nr, int chunk);
 void item_kill_tree(struct radix_tree_root *root);
 
-int tag_tagged_items(struct radix_tree_root *, pthread_mutex_t *,
-			unsigned long start, unsigned long end, unsigned batch,
-			unsigned iftag, unsigned thentag);
+int tag_tagged_items(struct xarray *, unsigned long start, unsigned long end,
+		unsigned batch, xa_mark_t iftag, xa_mark_t thentag);
 
 void xarray_tests(void);
 void tag_check(void);