Merge branch 'akpm' (patches from Andrew)

Merge more updates from Andrew Morton:

 - a few misc things

 - kexec updates

 - DMA-mapping updates to better support networking DMA operations

 - IPC updates

 - various MM changes to improve DAX fault handling

 - lots of radix-tree changes, mainly to the test suite. All leading up
   to reimplementing the IDA/IDR code to be a wrapper layer over the
   radix-tree. However the final trigger-pulling patch is held off for
   4.11.

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (114 commits)
  radix tree test suite: delete unused rcupdate.c
  radix tree test suite: add new tag check
  radix-tree: ensure counts are initialised
  radix tree test suite: cache recently freed objects
  radix tree test suite: add some more functionality
  idr: reduce the number of bits per level from 8 to 6
  rxrpc: abstract away knowledge of IDR internals
  tpm: use idr_find(), not idr_find_slowpath()
  idr: add ida_is_empty
  radix tree test suite: check multiorder iteration
  radix-tree: fix replacement for multiorder entries
  radix-tree: add radix_tree_split_preload()
  radix-tree: add radix_tree_split
  radix-tree: add radix_tree_join
  radix-tree: delete radix_tree_range_tag_if_tagged()
  radix-tree: delete radix_tree_locate_item()
  radix-tree: improve multiorder iterators
  btrfs: fix race in btrfs_free_dummy_fs_info()
  radix-tree: improve dump output
  radix-tree: make radix_tree_find_next_bit more useful
  ...

22 files changed, 805 insertions, 302 deletions

diff --git a/tools/testing/ktest/ktest.pl b/tools/testing/ktest/ktest.pl
index d08e214ec6e7..be93ab02b490 100755
--- a/tools/testing/ktest/ktest.pl
+++ b/tools/testing/ktest/ktest.pl
@@ -719,14 +719,14 @@ sub set_value {
 
     if ($buildonly && $lvalue =~ /^TEST_TYPE(\[.*\])?$/ && $prvalue ne "build") {
 	# Note if a test is something other than build, then we
-	# will need other manditory options.
+	# will need other mandatory options.
 	if ($prvalue ne "install") {
 	    # for bisect, we need to check BISECT_TYPE
 	    if ($prvalue ne "bisect") {
 		$buildonly = 0;
 	    }
 	} else {
-	    # install still limits some manditory options.
+	    # install still limits some mandatory options.
 	    $buildonly = 2;
 	}
     }
@@ -735,7 +735,7 @@ sub set_value {
 	if ($prvalue ne "install") {
 	    $buildonly = 0;
 	} else {
-	    # install still limits some manditory options.
+	    # install still limits some mandatory options.
 	    $buildonly = 2;
 	}
     }
@@ -3989,7 +3989,7 @@ sub make_min_config {
 		}
 	    }
 
-	    # Save off all the current mandidory configs
+	    # Save off all the current mandatory configs
 	    open (OUT, ">$temp_config")
 		or die "Can't write to $temp_config";
 	    foreach my $config (keys %keep_configs) {
diff --git a/tools/testing/radix-tree/Makefile b/tools/testing/radix-tree/Makefile
index f2e07f2fd4b4..3635e4d3eca7 100644
--- a/tools/testing/radix-tree/Makefile
+++ b/tools/testing/radix-tree/Makefile
@@ -1,10 +1,14 @@
 
-CFLAGS += -I. -g -O2 -Wall -D_LGPL_SOURCE
+CFLAGS += -I. -I../../include -g -O2 -Wall -D_LGPL_SOURCE
 LDFLAGS += -lpthread -lurcu
 TARGETS = main
 OFILES = main.o radix-tree.o linux.o test.o tag_check.o find_next_bit.o \
 	 regression1.o regression2.o regression3.o multiorder.o \
-	 iteration_check.o
+	 iteration_check.o benchmark.o
+
+ifdef BENCHMARK
+	CFLAGS += -DBENCHMARK=1
+endif
 
 targets: $(TARGETS)
 
@@ -14,7 +18,12 @@ main:	$(OFILES)
 clean:
 	$(RM) -f $(TARGETS) *.o radix-tree.c
 
-$(OFILES): *.h */*.h ../../../include/linux/radix-tree.h ../../include/linux/*.h
+find_next_bit.o: ../../lib/find_bit.c
+	$(CC) $(CFLAGS) -c -o $@ $<
+
+$(OFILES): *.h */*.h \
+	../../include/linux/*.h \
+	../../../include/linux/radix-tree.h
 
 radix-tree.c: ../../../lib/radix-tree.c
 	sed -e 's/^static //' -e 's/__always_inline //' -e 's/inline //' < $< > $@
diff --git a/tools/testing/radix-tree/benchmark.c b/tools/testing/radix-tree/benchmark.c
new file mode 100644
index 000000000000..215ca86c7605
--- /dev/null
+++ b/tools/testing/radix-tree/benchmark.c
@@ -0,0 +1,98 @@
+/*
+ * benchmark.c:
+ * Author: Konstantin Khlebnikov <koct9i@gmail.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>
+#include <linux/errno.h>
+#include <time.h>
+#include "test.h"
+
+#define NSEC_PER_SEC	1000000000L
+
+static long long benchmark_iter(struct radix_tree_root *root, bool tagged)
+{
+	volatile unsigned long sink = 0;
+	struct radix_tree_iter iter;
+	struct timespec start, finish;
+	long long nsec;
+	int l, loops = 1;
+	void **slot;
+
+#ifdef BENCHMARK
+again:
+#endif
+	clock_gettime(CLOCK_MONOTONIC, &start);
+	for (l = 0; l < loops; l++) {
+		if (tagged) {
+			radix_tree_for_each_tagged(slot, root, &iter, 0, 0)
+				sink ^= (unsigned long)slot;
+		} else {
+			radix_tree_for_each_slot(slot, root, &iter, 0)
+				sink ^= (unsigned long)slot;
+		}
+	}
+	clock_gettime(CLOCK_MONOTONIC, &finish);
+
+	nsec = (finish.tv_sec - start.tv_sec) * NSEC_PER_SEC +
+	       (finish.tv_nsec - start.tv_nsec);
+
+#ifdef BENCHMARK
+	if (loops == 1 && nsec * 5 < NSEC_PER_SEC) {
+		loops = NSEC_PER_SEC / nsec / 4 + 1;
+		goto again;
+	}
+#endif
+
+	nsec /= loops;
+	return nsec;
+}
+
+static void benchmark_size(unsigned long size, unsigned long step, int order)
+{
+	RADIX_TREE(tree, GFP_KERNEL);
+	long long normal, tagged;
+	unsigned long index;
+
+	for (index = 0 ; index < size ; index += step) {
+		item_insert_order(&tree, index, order);
+		radix_tree_tag_set(&tree, index, 0);
+	}
+
+	tagged = benchmark_iter(&tree, true);
+	normal = benchmark_iter(&tree, false);
+
+	printf("Size %ld, step %6ld, order %d tagged %10lld ns, normal %10lld ns\n",
+		size, step, order, tagged, normal);
+
+	item_kill_tree(&tree);
+	rcu_barrier();
+}
+
+void benchmark(void)
+{
+	unsigned long size[] = {1 << 10, 1 << 20, 0};
+	unsigned long step[] = {1, 2, 7, 15, 63, 64, 65,
+				128, 256, 512, 12345, 0};
+	int c, s;
+
+	printf("starting benchmarks\n");
+	printf("RADIX_TREE_MAP_SHIFT = %d\n", RADIX_TREE_MAP_SHIFT);
+
+	for (c = 0; size[c]; c++)
+		for (s = 0; step[s]; s++)
+			benchmark_size(size[c], step[s], 0);
+
+	for (c = 0; size[c]; c++)
+		for (s = 0; step[s]; s++)
+			benchmark_size(size[c], step[s] << 9, 9);
+}
diff --git a/tools/testing/radix-tree/find_next_bit.c b/tools/testing/radix-tree/find_next_bit.c
deleted file mode 100644
index d1c2178bb2d4..000000000000
--- a/tools/testing/radix-tree/find_next_bit.c
+++ /dev/null
@@ -1,57 +0,0 @@
-/* find_next_bit.c: fallback find next bit implementation
- *
- * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
- * Written by David Howells (dhowells@redhat.com)
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version
- * 2 of the License, or (at your option) any later version.
- */
-
-#include <linux/types.h>
-#include <linux/bitops.h>
-
-#define BITOP_WORD(nr)		((nr) / BITS_PER_LONG)
-
-/*
- * Find the next set bit in a memory region.
- */
-unsigned long find_next_bit(const unsigned long *addr, unsigned long size,
-			    unsigned long offset)
-{
-	const unsigned long *p = addr + BITOP_WORD(offset);
-	unsigned long result = offset & ~(BITS_PER_LONG-1);
-	unsigned long tmp;
-
-	if (offset >= size)
-		return size;
-	size -= result;
-	offset %= BITS_PER_LONG;
-	if (offset) {
-		tmp = *(p++);
-		tmp &= (~0UL << offset);
-		if (size < BITS_PER_LONG)
-			goto found_first;
-		if (tmp)
-			goto found_middle;
-		size -= BITS_PER_LONG;
-		result += BITS_PER_LONG;
-	}
-	while (size & ~(BITS_PER_LONG-1)) {
-		if ((tmp = *(p++)))
-			goto found_middle;
-		result += BITS_PER_LONG;
-		size -= BITS_PER_LONG;
-	}
-	if (!size)
-		return result;
-	tmp = *p;
-
-found_first:
-	tmp &= (~0UL >> (BITS_PER_LONG - size));
-	if (tmp == 0UL)		/* Are any bits set? */
-		return result + size;	/* Nope. */
-found_middle:
-	return result + __ffs(tmp);
-}
diff --git a/tools/testing/radix-tree/iteration_check.c b/tools/testing/radix-tree/iteration_check.c
index 9adb8e7415a6..7572b7ed930e 100644
--- a/tools/testing/radix-tree/iteration_check.c
+++ b/tools/testing/radix-tree/iteration_check.c
@@ -16,35 +16,50 @@
 #include <pthread.h>
 #include "test.h"
 
-#define NUM_THREADS 4
-#define TAG 0
+#define NUM_THREADS	5
+#define MAX_IDX		100
+#define TAG		0
+#define NEW_TAG		1
+
 static pthread_mutex_t tree_lock = PTHREAD_MUTEX_INITIALIZER;
 static pthread_t threads[NUM_THREADS];
-RADIX_TREE(tree, GFP_KERNEL);
-bool test_complete;
+static unsigned int seeds[3];
+static RADIX_TREE(tree, GFP_KERNEL);
+static bool test_complete;
+static int max_order;
 
 /* relentlessly fill the tree with tagged entries */
 static void *add_entries_fn(void *arg)
 {
-	int pgoff;
+	rcu_register_thread();
 
 	while (!test_complete) {
-		for (pgoff = 0; pgoff < 100; pgoff++) {
+		unsigned long pgoff;
+		int order;
+
+		for (pgoff = 0; pgoff < MAX_IDX; pgoff++) {
 			pthread_mutex_lock(&tree_lock);
-			if (item_insert(&tree, pgoff) == 0)
-				item_tag_set(&tree, pgoff, TAG);
+			for (order = max_order; order >= 0; order--) {
+				if (item_insert_order(&tree, pgoff, order)
+						== 0) {
+					item_tag_set(&tree, pgoff, TAG);
+					break;
+				}
+			}
 			pthread_mutex_unlock(&tree_lock);
 		}
 	}
 
+	rcu_unregister_thread();
+
 	return NULL;
 }
 
 /*
  * Iterate over the tagged entries, doing a radix_tree_iter_retry() as we find
  * things that have been removed and randomly resetting our iteration to the
- * next chunk with radix_tree_iter_next().  Both radix_tree_iter_retry() and
- * radix_tree_iter_next() cause radix_tree_next_slot() to be called with a
+ * next chunk with radix_tree_iter_resume().  Both radix_tree_iter_retry() and
+ * radix_tree_iter_resume() cause radix_tree_next_slot() to be called with a
  * NULL 'slot' variable.
  */
 static void *tagged_iteration_fn(void *arg)
@@ -52,17 +67,12 @@ static void *tagged_iteration_fn(void *arg)
 	struct radix_tree_iter iter;
 	void **slot;
 
+	rcu_register_thread();
+
 	while (!test_complete) {
 		rcu_read_lock();
 		radix_tree_for_each_tagged(slot, &tree, &iter, 0, TAG) {
-			void *entry;
-			int i;
-
-			/* busy wait to let removals happen */
-			for (i = 0; i < 1000000; i++)
-				;
-
-			entry = radix_tree_deref_slot(slot);
+			void *entry = radix_tree_deref_slot(slot);
 			if (unlikely(!entry))
 				continue;
 
@@ -71,20 +81,26 @@ static void *tagged_iteration_fn(void *arg)
 				continue;
 			}
 
-			if (rand() % 50 == 0)
-				slot = radix_tree_iter_next(&iter);
+			if (rand_r(&seeds[0]) % 50 == 0) {
+				slot = radix_tree_iter_resume(slot, &iter);
+				rcu_read_unlock();
+				rcu_barrier();
+				rcu_read_lock();
+			}
 		}
 		rcu_read_unlock();
 	}
 
+	rcu_unregister_thread();
+
 	return NULL;
 }
 
 /*
  * Iterate over the entries, doing a radix_tree_iter_retry() as we find things
  * that have been removed and randomly resetting our iteration to the next
- * chunk with radix_tree_iter_next().  Both radix_tree_iter_retry() and
- * radix_tree_iter_next() cause radix_tree_next_slot() to be called with a
+ * chunk with radix_tree_iter_resume().  Both radix_tree_iter_retry() and
+ * radix_tree_iter_resume() cause radix_tree_next_slot() to be called with a
  * NULL 'slot' variable.
  */
 static void *untagged_iteration_fn(void *arg)
@@ -92,17 +108,12 @@ static void *untagged_iteration_fn(void *arg)
 	struct radix_tree_iter iter;
 	void **slot;
 
+	rcu_register_thread();
+
 	while (!test_complete) {
 		rcu_read_lock();
 		radix_tree_for_each_slot(slot, &tree, &iter, 0) {
-			void *entry;
-			int i;
-
-			/* busy wait to let removals happen */
-			for (i = 0; i < 1000000; i++)
-				;
-
-			entry = radix_tree_deref_slot(slot);
+			void *entry = radix_tree_deref_slot(slot);
 			if (unlikely(!entry))
 				continue;
 
@@ -111,12 +122,18 @@ static void *untagged_iteration_fn(void *arg)
 				continue;
 			}
 
-			if (rand() % 50 == 0)
-				slot = radix_tree_iter_next(&iter);
+			if (rand_r(&seeds[1]) % 50 == 0) {
+				slot = radix_tree_iter_resume(slot, &iter);
+				rcu_read_unlock();
+				rcu_barrier();
+				rcu_read_lock();
+			}
 		}
 		rcu_read_unlock();
 	}
 
+	rcu_unregister_thread();
+
 	return NULL;
 }
 
@@ -126,47 +143,71 @@ static void *untagged_iteration_fn(void *arg)
  */
 static void *remove_entries_fn(void *arg)
 {
+	rcu_register_thread();
+
 	while (!test_complete) {
 		int pgoff;
 
-		pgoff = rand() % 100;
+		pgoff = rand_r(&seeds[2]) % MAX_IDX;
 
 		pthread_mutex_lock(&tree_lock);
 		item_delete(&tree, pgoff);
 		pthread_mutex_unlock(&tree_lock);
 	}
 
+	rcu_unregister_thread();
+
+	return NULL;
+}
+
+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);
+	}
+	rcu_unregister_thread();
 	return NULL;
 }
 
 /* This is a unit test for a bug found by the syzkaller tester */
-void iteration_test(void)
+void iteration_test(unsigned order, unsigned test_duration)
 {
 	int i;
 
-	printf("Running iteration tests for 10 seconds\n");
+	printf("Running %siteration tests for %d seconds\n",
+			order > 0 ? "multiorder " : "", test_duration);
 
-	srand(time(0));
+	max_order = order;
 	test_complete = false;
 
+	for (i = 0; i < 3; i++)
+		seeds[i] = rand();
+
 	if (pthread_create(&threads[0], NULL, tagged_iteration_fn, NULL)) {
-		perror("pthread_create");
+		perror("create tagged iteration thread");
 		exit(1);
 	}
 	if (pthread_create(&threads[1], NULL, untagged_iteration_fn, NULL)) {
-		perror("pthread_create");
+		perror("create untagged iteration thread");
 		exit(1);
 	}
 	if (pthread_create(&threads[2], NULL, add_entries_fn, NULL)) {
-		perror("pthread_create");
+		perror("create add entry thread");
 		exit(1);
 	}
 	if (pthread_create(&threads[3], NULL, remove_entries_fn, NULL)) {
-		perror("pthread_create");
+		perror("create remove entry thread");
+		exit(1);
+	}
+	if (pthread_create(&threads[4], NULL, tag_entries_fn, NULL)) {
+		perror("create tag entry thread");
 		exit(1);
 	}
 
-	sleep(10);
+	sleep(test_duration);
 	test_complete = true;
 
 	for (i = 0; i < NUM_THREADS; i++) {
diff --git a/tools/testing/radix-tree/linux.c b/tools/testing/radix-tree/linux.c
index 154823737b20..d31ea7c9abec 100644
--- a/tools/testing/radix-tree/linux.c
+++ b/tools/testing/radix-tree/linux.c
@@ -1,14 +1,26 @@
 #include <stdlib.h>
 #include <string.h>
 #include <malloc.h>
+#include <pthread.h>
 #include <unistd.h>
 #include <assert.h>
 
 #include <linux/mempool.h>
+#include <linux/poison.h>
 #include <linux/slab.h>
+#include <linux/radix-tree.h>
 #include <urcu/uatomic.h>
 
 int nr_allocated;
+int preempt_count;
+
+struct kmem_cache {
+	pthread_mutex_t lock;
+	int size;
+	int nr_objs;
+	void *objs;
+	void (*ctor)(void *);
+};
 
 void *mempool_alloc(mempool_t *pool, int gfp_mask)
 {
@@ -33,19 +45,59 @@ mempool_t *mempool_create(int min_nr, mempool_alloc_t *alloc_fn,
 
 void *kmem_cache_alloc(struct kmem_cache *cachep, int flags)
 {
-	void *ret = malloc(cachep->size);
-	if (cachep->ctor)
-		cachep->ctor(ret);
+	struct radix_tree_node *node;
+
+	if (flags & __GFP_NOWARN)
+		return NULL;
+
+	pthread_mutex_lock(&cachep->lock);
+	if (cachep->nr_objs) {
+		cachep->nr_objs--;
+		node = cachep->objs;
+		cachep->objs = node->private_data;
+		pthread_mutex_unlock(&cachep->lock);
+		node->private_data = NULL;
+	} else {
+		pthread_mutex_unlock(&cachep->lock);
+		node = malloc(cachep->size);
+		if (cachep->ctor)
+			cachep->ctor(node);
+	}
+
 	uatomic_inc(&nr_allocated);
-	return ret;
+	return node;
 }
 
 void kmem_cache_free(struct kmem_cache *cachep, void *objp)
 {
 	assert(objp);
 	uatomic_dec(&nr_allocated);
-	memset(objp, 0, cachep->size);
-	free(objp);
+	pthread_mutex_lock(&cachep->lock);
+	if (cachep->nr_objs > 10) {
+		memset(objp, POISON_FREE, cachep->size);
+		free(objp);
+	} else {
+		struct radix_tree_node *node = objp;
+		cachep->nr_objs++;
+		node->private_data = cachep->objs;
+		cachep->objs = node;
+	}
+	pthread_mutex_unlock(&cachep->lock);
+}
+
+void *kmalloc(size_t size, gfp_t gfp)
+{
+	void *ret = malloc(size);
+	uatomic_inc(&nr_allocated);
+	return ret;
+}
+
+void kfree(void *p)
+{
+	if (!p)
+		return;
+	uatomic_dec(&nr_allocated);
+	free(p);
 }
 
 struct kmem_cache *
@@ -54,7 +106,10 @@ kmem_cache_create(const char *name, size_t size, size_t offset,
 {
 	struct kmem_cache *ret = malloc(sizeof(*ret));
 
+	pthread_mutex_init(&ret->lock, NULL);
 	ret->size = size;
+	ret->nr_objs = 0;
+	ret->objs = NULL;
 	ret->ctor = ctor;
 	return ret;
 }
diff --git a/tools/testing/radix-tree/linux/bitops.h b/tools/testing/radix-tree/linux/bitops.h
index 71d58427ab60..a13e9bc76eec 100644
--- a/tools/testing/radix-tree/linux/bitops.h
+++ b/tools/testing/radix-tree/linux/bitops.h
@@ -2,9 +2,14 @@
 #define _ASM_GENERIC_BITOPS_NON_ATOMIC_H_
 
 #include <linux/types.h>
+#include <linux/bitops/find.h>
+#include <linux/bitops/hweight.h>
+#include <linux/kernel.h>
 
-#define BITOP_MASK(nr)		(1UL << ((nr) % BITS_PER_LONG))
-#define BITOP_WORD(nr)		((nr) / BITS_PER_LONG)
+#define BIT_MASK(nr)		(1UL << ((nr) % BITS_PER_LONG))
+#define BIT_WORD(nr)		((nr) / BITS_PER_LONG)
+#define BITS_PER_BYTE		8
+#define BITS_TO_LONGS(nr)	DIV_ROUND_UP(nr, BITS_PER_BYTE * sizeof(long))
 
 /**
  * __set_bit - Set a bit in memory
@@ -17,16 +22,16 @@
  */
 static inline void __set_bit(int nr, volatile unsigned long *addr)
 {
-	unsigned long mask = BITOP_MASK(nr);
-	unsigned long *p = ((unsigned long *)addr) + BITOP_WORD(nr);
+	unsigned long mask = BIT_MASK(nr);
+	unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
 
 	*p  |= mask;
 }
 
 static inline void __clear_bit(int nr, volatile unsigned long *addr)
 {
-	unsigned long mask = BITOP_MASK(nr);
-	unsigned long *p = ((unsigned long *)addr) + BITOP_WORD(nr);
+	unsigned long mask = BIT_MASK(nr);
+	unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
 
 	*p &= ~mask;
 }
@@ -42,8 +47,8 @@ static inline void __clear_bit(int nr, volatile unsigned long *addr)
  */
 static inline void __change_bit(int nr, volatile unsigned long *addr)
 {
-	unsigned long mask = BITOP_MASK(nr);
-	unsigned long *p = ((unsigned long *)addr) + BITOP_WORD(nr);
+	unsigned long mask = BIT_MASK(nr);
+	unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
 
 	*p ^= mask;
 }
@@ -59,8 +64,8 @@ static inline void __change_bit(int nr, volatile unsigned long *addr)
  */
 static inline int __test_and_set_bit(int nr, volatile unsigned long *addr)
 {
-	unsigned long mask = BITOP_MASK(nr);
-	unsigned long *p = ((unsigned long *)addr) + BITOP_WORD(nr);
+	unsigned long mask = BIT_MASK(nr);
+	unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
 	unsigned long old = *p;
 
 	*p = old | mask;
@@ -78,8 +83,8 @@ static inline int __test_and_set_bit(int nr, volatile unsigned long *addr)
  */
 static inline int __test_and_clear_bit(int nr, volatile unsigned long *addr)
 {
-	unsigned long mask = BITOP_MASK(nr);
-	unsigned long *p = ((unsigned long *)addr) + BITOP_WORD(nr);
+	unsigned long mask = BIT_MASK(nr);
+	unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
 	unsigned long old = *p;
 
 	*p = old & ~mask;
@@ -90,8 +95,8 @@ static inline int __test_and_clear_bit(int nr, volatile unsigned long *addr)
 static inline int __test_and_change_bit(int nr,
 					    volatile unsigned long *addr)
 {
-	unsigned long mask = BITOP_MASK(nr);
-	unsigned long *p = ((unsigned long *)addr) + BITOP_WORD(nr);
+	unsigned long mask = BIT_MASK(nr);
+	unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
 	unsigned long old = *p;
 
 	*p = old ^ mask;
@@ -105,7 +110,7 @@ static inline int __test_and_change_bit(int nr,
  */
 static inline int test_bit(int nr, const volatile unsigned long *addr)
 {
-	return 1UL & (addr[BITOP_WORD(nr)] >> (nr & (BITS_PER_LONG-1)));
+	return 1UL & (addr[BIT_WORD(nr)] >> (nr & (BITS_PER_LONG-1)));
 }
 
 /**
@@ -147,4 +152,9 @@ unsigned long find_next_bit(const unsigned long *addr,
 			    unsigned long size,
 			    unsigned long offset);
 
+static inline unsigned long hweight_long(unsigned long w)
+{
+	return sizeof(w) == 4 ? hweight32(w) : hweight64(w);
+}
+
 #endif /* _ASM_GENERIC_BITOPS_NON_ATOMIC_H_ */
diff --git a/tools/testing/radix-tree/linux/bitops/non-atomic.h b/tools/testing/radix-tree/linux/bitops/non-atomic.h
index 46a825cf2ae1..6a1bcb9d2c4a 100644
--- a/tools/testing/radix-tree/linux/bitops/non-atomic.h
+++ b/tools/testing/radix-tree/linux/bitops/non-atomic.h
@@ -3,7 +3,6 @@
 
 #include <asm/types.h>
 
-#define BITOP_MASK(nr)		(1UL << ((nr) % BITS_PER_LONG))
 #define BITOP_WORD(nr)		((nr) / BITS_PER_LONG)
 
 /**
@@ -17,7 +16,7 @@
  */
 static inline void __set_bit(int nr, volatile unsigned long *addr)
 {
-	unsigned long mask = BITOP_MASK(nr);
+	unsigned long mask = BIT_MASK(nr);
 	unsigned long *p = ((unsigned long *)addr) + BITOP_WORD(nr);
 
 	*p  |= mask;
@@ -25,7 +24,7 @@ static inline void __set_bit(int nr, volatile unsigned long *addr)
 
 static inline void __clear_bit(int nr, volatile unsigned long *addr)
 {
-	unsigned long mask = BITOP_MASK(nr);
+	unsigned long mask = BIT_MASK(nr);
 	unsigned long *p = ((unsigned long *)addr) + BITOP_WORD(nr);
 
 	*p &= ~mask;
@@ -42,7 +41,7 @@ static inline void __clear_bit(int nr, volatile unsigned long *addr)
  */
 static inline void __change_bit(int nr, volatile unsigned long *addr)
 {
-	unsigned long mask = BITOP_MASK(nr);
+	unsigned long mask = BIT_MASK(nr);
 	unsigned long *p = ((unsigned long *)addr) + BITOP_WORD(nr);
 
 	*p ^= mask;
@@ -59,7 +58,7 @@ static inline void __change_bit(int nr, volatile unsigned long *addr)
  */
 static inline int __test_and_set_bit(int nr, volatile unsigned long *addr)
 {
-	unsigned long mask = BITOP_MASK(nr);
+	unsigned long mask = BIT_MASK(nr);
 	unsigned long *p = ((unsigned long *)addr) + BITOP_WORD(nr);
 	unsigned long old = *p;
 
@@ -78,7 +77,7 @@ static inline int __test_and_set_bit(int nr, volatile unsigned long *addr)
  */
 static inline int __test_and_clear_bit(int nr, volatile unsigned long *addr)
 {
-	unsigned long mask = BITOP_MASK(nr);
+	unsigned long mask = BIT_MASK(nr);
 	unsigned long *p = ((unsigned long *)addr) + BITOP_WORD(nr);
 	unsigned long old = *p;
 
@@ -90,7 +89,7 @@ static inline int __test_and_clear_bit(int nr, volatile unsigned long *addr)
 static inline int __test_and_change_bit(int nr,
 					    volatile unsigned long *addr)
 {
-	unsigned long mask = BITOP_MASK(nr);
+	unsigned long mask = BIT_MASK(nr);
 	unsigned long *p = ((unsigned long *)addr) + BITOP_WORD(nr);
 	unsigned long old = *p;
 
diff --git a/tools/testing/radix-tree/linux/bug.h b/tools/testing/radix-tree/linux/bug.h
index ccbe444977df..23b8ed52f8c8 100644
--- a/tools/testing/radix-tree/linux/bug.h
+++ b/tools/testing/radix-tree/linux/bug.h
@@ -1 +1 @@
-#define WARN_ON_ONCE(x)		assert(x)
+#include "asm/bug.h"
diff --git a/tools/testing/radix-tree/linux/gfp.h b/tools/testing/radix-tree/linux/gfp.h
index 5201b915f631..5b09b2ce6c33 100644
--- a/tools/testing/radix-tree/linux/gfp.h
+++ b/tools/testing/radix-tree/linux/gfp.h
@@ -3,8 +3,24 @@
 
 #define __GFP_BITS_SHIFT 26
 #define __GFP_BITS_MASK ((gfp_t)((1 << __GFP_BITS_SHIFT) - 1))
-#define __GFP_WAIT 1
-#define __GFP_ACCOUNT 0
-#define __GFP_NOWARN 0
+
+#define __GFP_HIGH		0x20u
+#define __GFP_IO		0x40u
+#define __GFP_FS		0x80u
+#define __GFP_NOWARN		0x200u
+#define __GFP_ATOMIC		0x80000u
+#define __GFP_ACCOUNT		0x100000u
+#define __GFP_DIRECT_RECLAIM	0x400000u
+#define __GFP_KSWAPD_RECLAIM	0x2000000u
+
+#define __GFP_RECLAIM		(__GFP_DIRECT_RECLAIM|__GFP_KSWAPD_RECLAIM)
+
+#define GFP_ATOMIC		(__GFP_HIGH|__GFP_ATOMIC|__GFP_KSWAPD_RECLAIM)
+#define GFP_KERNEL		(__GFP_RECLAIM | __GFP_IO | __GFP_FS)
+
+static inline bool gfpflags_allow_blocking(const gfp_t gfp_flags)
+{
+	return !!(gfp_flags & __GFP_DIRECT_RECLAIM);
+}
 
 #endif
diff --git a/tools/testing/radix-tree/linux/kernel.h b/tools/testing/radix-tree/linux/kernel.h
index be98a47b4e1b..9b43b4975d83 100644
--- a/tools/testing/radix-tree/linux/kernel.h
+++ b/tools/testing/radix-tree/linux/kernel.h
@@ -8,9 +8,14 @@
 #include <limits.h>
 
 #include "../../include/linux/compiler.h"
+#include "../../include/linux/err.h"
 #include "../../../include/linux/kconfig.h"
 
+#ifdef BENCHMARK
+#define RADIX_TREE_MAP_SHIFT	6
+#else
 #define RADIX_TREE_MAP_SHIFT	3
+#endif
 
 #ifndef NULL
 #define NULL	0
@@ -43,4 +48,17 @@ static inline int in_interrupt(void)
 {
 	return 0;
 }
+
+/*
+ * This looks more complex than it should be. But we need to
+ * get the type for the ~ right in round_down (it needs to be
+ * as wide as the result!), and we want to evaluate the macro
+ * arguments just once each.
+ */
+#define __round_mask(x, y) ((__typeof__(x))((y)-1))
+#define round_up(x, y) ((((x)-1) | __round_mask(x, y))+1)
+#define round_down(x, y) ((x) & ~__round_mask(x, y))
+
+#define xchg(ptr, x)	uatomic_xchg(ptr, x)
+
 #endif /* _KERNEL_H */
diff --git a/tools/testing/radix-tree/linux/preempt.h b/tools/testing/radix-tree/linux/preempt.h
index 6210672e3baa..65c04c226965 100644
--- a/tools/testing/radix-tree/linux/preempt.h
+++ b/tools/testing/radix-tree/linux/preempt.h
@@ -1,4 +1,4 @@
-/* */
+extern int preempt_count;
 
-#define preempt_disable() do { } while (0)
-#define preempt_enable() do { } while (0)
+#define preempt_disable()	uatomic_inc(&preempt_count)
+#define preempt_enable()	uatomic_dec(&preempt_count)
diff --git a/tools/testing/radix-tree/linux/slab.h b/tools/testing/radix-tree/linux/slab.h
index 6d5a34770fd4..e40337f41a38 100644
--- a/tools/testing/radix-tree/linux/slab.h
+++ b/tools/testing/radix-tree/linux/slab.h
@@ -7,15 +7,8 @@
 #define SLAB_PANIC 2
 #define SLAB_RECLAIM_ACCOUNT    0x00020000UL            /* Objects are reclaimable */
 
-static inline int gfpflags_allow_blocking(gfp_t mask)
-{
-	return 1;
-}
-
-struct kmem_cache {
-	int size;
-	void (*ctor)(void *);
-};
+void *kmalloc(size_t size, gfp_t);
+void kfree(void *);
 
 void *kmem_cache_alloc(struct kmem_cache *cachep, int flags);
 void kmem_cache_free(struct kmem_cache *cachep, void *objp);
diff --git a/tools/testing/radix-tree/linux/types.h b/tools/testing/radix-tree/linux/types.h
index faa0b6ff9ca8..8491d89873bb 100644
--- a/tools/testing/radix-tree/linux/types.h
+++ b/tools/testing/radix-tree/linux/types.h
@@ -6,8 +6,6 @@
 #define __rcu
 #define __read_mostly
 
-#define BITS_PER_LONG (sizeof(long) * 8)
-
 static inline void INIT_LIST_HEAD(struct list_head *list)
 {
 	list->next = list;
diff --git a/tools/testing/radix-tree/main.c b/tools/testing/radix-tree/main.c
index daa9010693e8..f7e9801a6754 100644
--- a/tools/testing/radix-tree/main.c
+++ b/tools/testing/radix-tree/main.c
@@ -67,7 +67,6 @@ void big_gang_check(bool long_run)
 
 	for (i = 0; i < (long_run ? 1000 : 3); i++) {
 		__big_gang_check();
-		srand(time(0));
 		printf("%d ", i);
 		fflush(stdout);
 	}
@@ -206,8 +205,7 @@ void copy_tag_check(void)
 	}
 
 //	printf("\ncopying tags...\n");
-	cur = start;
-	tagged = radix_tree_range_tag_if_tagged(&tree, &cur, end, ITEMS, 0, 1);
+	tagged = tag_tagged_items(&tree, NULL, start, end, ITEMS, 0, 1);
 
 //	printf("checking copied tags\n");
 	assert(tagged == count);
@@ -215,16 +213,13 @@ void copy_tag_check(void)
 
 	/* Copy tags in several rounds */
 //	printf("\ncopying tags...\n");
-	cur = start;
-	do {
-		tmp = rand() % (count/10+2);
-		tagged = radix_tree_range_tag_if_tagged(&tree, &cur, end, tmp, 0, 2);
-	} while (tmp == tagged);
+	tmp = rand() % (count / 10 + 2);
+	tagged = tag_tagged_items(&tree, NULL, start, end, tmp, 0, 2);
+	assert(tagged == count);
 
 //	printf("%lu %lu %lu\n", tagged, tmp, count);
 //	printf("checking copied tags\n");
 	check_copied_tags(&tree, start, end, idx, ITEMS, 0, 2);
-	assert(tagged < tmp);
 	verify_tag_consistency(&tree, 0);
 	verify_tag_consistency(&tree, 1);
 	verify_tag_consistency(&tree, 2);
@@ -240,7 +235,7 @@ static void __locate_check(struct radix_tree_root *tree, unsigned long index,
 
 	item_insert_order(tree, index, order);
 	item = item_lookup(tree, index);
-	index2 = radix_tree_locate_item(tree, item);
+	index2 = find_item(tree, item);
 	if (index != index2) {
 		printf("index %ld order %d inserted; found %ld\n",
 			index, order, index2);
@@ -274,17 +269,17 @@ static void locate_check(void)
 			     index += (1UL << order)) {
 				__locate_check(&tree, index + offset, order);
 			}
-			if (radix_tree_locate_item(&tree, &tree) != -1)
+			if (find_item(&tree, &tree) != -1)
 				abort();
 
 			item_kill_tree(&tree);
 		}
 	}
 
-	if (radix_tree_locate_item(&tree, &tree) != -1)
+	if (find_item(&tree, &tree) != -1)
 		abort();
 	__locate_check(&tree, -1, 0);
-	if (radix_tree_locate_item(&tree, &tree) != -1)
+	if (find_item(&tree, &tree) != -1)
 		abort();
 	item_kill_tree(&tree);
 }
@@ -293,50 +288,80 @@ static void single_thread_tests(bool long_run)
 {
 	int i;
 
-	printf("starting single_thread_tests: %d allocated\n", nr_allocated);
+	printf("starting single_thread_tests: %d allocated, preempt %d\n",
+		nr_allocated, preempt_count);
 	multiorder_checks();
-	printf("after multiorder_check: %d allocated\n", nr_allocated);
+	rcu_barrier();
+	printf("after multiorder_check: %d allocated, preempt %d\n",
+		nr_allocated, preempt_count);
 	locate_check();
-	printf("after locate_check: %d allocated\n", nr_allocated);
+	rcu_barrier();
+	printf("after locate_check: %d allocated, preempt %d\n",
+		nr_allocated, preempt_count);
 	tag_check();
-	printf("after tag_check: %d allocated\n", nr_allocated);
+	rcu_barrier();
+	printf("after tag_check: %d allocated, preempt %d\n",
+		nr_allocated, preempt_count);
 	gang_check();
-	printf("after gang_check: %d allocated\n", nr_allocated);
+	rcu_barrier();
+	printf("after gang_check: %d allocated, preempt %d\n",
+		nr_allocated, preempt_count);
 	add_and_check();
-	printf("after add_and_check: %d allocated\n", nr_allocated);
+	rcu_barrier();
+	printf("after add_and_check: %d allocated, preempt %d\n",
+		nr_allocated, preempt_count);
 	dynamic_height_check();
-	printf("after dynamic_height_check: %d allocated\n", nr_allocated);
+	rcu_barrier();
+	printf("after dynamic_height_check: %d allocated, preempt %d\n",
+		nr_allocated, preempt_count);
 	big_gang_check(long_run);
-	printf("after big_gang_check: %d allocated\n", nr_allocated);
+	rcu_barrier();
+	printf("after big_gang_check: %d allocated, preempt %d\n",
+		nr_allocated, preempt_count);
 	for (i = 0; i < (long_run ? 2000 : 3); i++) {
 		copy_tag_check();
 		printf("%d ", i);
 		fflush(stdout);
 	}
-	printf("after copy_tag_check: %d allocated\n", nr_allocated);
+	rcu_barrier();
+	printf("after copy_tag_check: %d allocated, preempt %d\n",
+		nr_allocated, preempt_count);
 }
 
 int main(int argc, char **argv)
 {
 	bool long_run = false;
 	int opt;
+	unsigned int seed = time(NULL);
 
-	while ((opt = getopt(argc, argv, "l")) != -1) {
+	while ((opt = getopt(argc, argv, "ls:")) != -1) {
 		if (opt == 'l')
 			long_run = true;
+		else if (opt == 's')
+			seed = strtoul(optarg, NULL, 0);
 	}
 
+	printf("random seed %u\n", seed);
+	srand(seed);
+
 	rcu_register_thread();
 	radix_tree_init();
 
 	regression1_test();
 	regression2_test();
 	regression3_test();
-	iteration_test();
+	iteration_test(0, 10);
+	iteration_test(7, 20);
 	single_thread_tests(long_run);
 
-	sleep(1);
-	printf("after sleep(1): %d allocated\n", nr_allocated);
+	/* Free any remaining preallocated nodes */
+	radix_tree_cpu_dead(0);
+
+	benchmark();
+
+	rcu_barrier();
+	printf("after rcu_barrier: %d allocated, preempt %d\n",
+		nr_allocated, preempt_count);
 	rcu_unregister_thread();
 
 	exit(0);
diff --git a/tools/testing/radix-tree/multiorder.c b/tools/testing/radix-tree/multiorder.c
index d1be94667a30..f79812a5e070 100644
--- a/tools/testing/radix-tree/multiorder.c
+++ b/tools/testing/radix-tree/multiorder.c
@@ -26,7 +26,6 @@ static void __multiorder_tag_test(int index, int order)
 {
 	RADIX_TREE(tree, GFP_KERNEL);
 	int base, err, i;
-	unsigned long first = 0;
 
 	/* our canonical entry */
 	base = index & ~((1 << order) - 1);
@@ -60,7 +59,7 @@ static void __multiorder_tag_test(int index, int order)
 		assert(!radix_tree_tag_get(&tree, i, 1));
 	}
 
-	assert(radix_tree_range_tag_if_tagged(&tree, &first, ~0UL, 10, 0, 1) == 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) {
@@ -76,8 +75,27 @@ static void __multiorder_tag_test(int index, int order)
 	item_kill_tree(&tree);
 }
 
+static void __multiorder_tag_test2(unsigned order, unsigned long index2)
+{
+	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);
@@ -117,6 +135,10 @@ static void multiorder_tag_tests(void)
 	__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)
@@ -125,7 +147,7 @@ static void multiorder_check(unsigned long index, int order)
 	unsigned long min = index & ~((1UL << order) - 1);
 	unsigned long max = min + (1UL << order);
 	void **slot;
-	struct item *item2 = item_create(min);
+	struct item *item2 = item_create(min, order);
 	RADIX_TREE(tree, GFP_KERNEL);
 
 	printf("Multiorder index %ld, order %d\n", index, order);
@@ -231,11 +253,14 @@ void multiorder_iteration(void)
 		radix_tree_for_each_slot(slot, &tree, &iter, j) {
 			int height = order[i] / RADIX_TREE_MAP_SHIFT;
 			int shift = height * RADIX_TREE_MAP_SHIFT;
-			int mask = (1 << order[i]) - 1;
+			unsigned long mask = (1UL << order[i]) - 1;
+			struct item *item = *slot;
 
-			assert(iter.index >= (index[i] &~ mask));
-			assert(iter.index <= (index[i] | mask));
+			assert((iter.index | mask) == (index[i] | mask));
 			assert(iter.shift == shift);
+			assert(!radix_tree_is_internal_node(item));
+			assert((item->index | mask) == (index[i] | mask));
+			assert(item->order == order[i]);
 			i++;
 		}
 	}
@@ -248,7 +273,6 @@ void multiorder_tagged_iteration(void)
 	RADIX_TREE(tree, GFP_KERNEL);
 	struct radix_tree_iter iter;
 	void **slot;
-	unsigned long first = 0;
 	int i, j;
 
 	printf("Multiorder tagged iteration test\n");
@@ -269,7 +293,7 @@ void multiorder_tagged_iteration(void)
 		assert(radix_tree_tag_set(&tree, tag_index[i], 1));
 
 	for (j = 0; j < 256; j++) {
-		int mask, k;
+		int k;
 
 		for (i = 0; i < TAG_ENTRIES; i++) {
 			for (k = i; index[k] < tag_index[i]; k++)
@@ -279,18 +303,22 @@ void multiorder_tagged_iteration(void)
 		}
 
 		radix_tree_for_each_tagged(slot, &tree, &iter, j, 1) {
+			unsigned long mask;
+			struct item *item = *slot;
 			for (k = i; index[k] < tag_index[i]; k++)
 				;
-			mask = (1 << order[k]) - 1;
+			mask = (1UL << order[k]) - 1;
 
-			assert(iter.index >= (tag_index[i] &~ mask));
-			assert(iter.index <= (tag_index[i] | mask));
+			assert((iter.index | mask) == (tag_index[i] | mask));
+			assert(!radix_tree_is_internal_node(item));
+			assert((item->index | mask) == (tag_index[i] | mask));
+			assert(item->order == order[k]);
 			i++;
 		}
 	}
 
-	radix_tree_range_tag_if_tagged(&tree, &first, ~0UL,
-					MT_NUM_ENTRIES, 1, 2);
+	assert(tag_tagged_items(&tree, NULL, 0, ~0UL, TAG_ENTRIES, 1, 2) ==
+				TAG_ENTRIES);
 
 	for (j = 0; j < 256; j++) {
 		int mask, k;
@@ -303,19 +331,21 @@ void multiorder_tagged_iteration(void)
 		}
 
 		radix_tree_for_each_tagged(slot, &tree, &iter, j, 2) {
+			struct item *item = *slot;
 			for (k = i; index[k] < tag_index[i]; k++)
 				;
 			mask = (1 << order[k]) - 1;
 
-			assert(iter.index >= (tag_index[i] &~ mask));
-			assert(iter.index <= (tag_index[i] | mask));
+			assert((iter.index | mask) == (tag_index[i] | mask));
+			assert(!radix_tree_is_internal_node(item));
+			assert((item->index | mask) == (tag_index[i] | mask));
+			assert(item->order == order[k]);
 			i++;
 		}
 	}
 
-	first = 1;
-	radix_tree_range_tag_if_tagged(&tree, &first, ~0UL,
-					MT_NUM_ENTRIES, 1, 0);
+	assert(tag_tagged_items(&tree, NULL, 1, ~0UL, MT_NUM_ENTRIES * 2, 1, 0)
+			== TAG_ENTRIES);
 	i = 0;
 	radix_tree_for_each_tagged(slot, &tree, &iter, 0, 0) {
 		assert(iter.index == tag_index[i]);
@@ -325,6 +355,261 @@ void multiorder_tagged_iteration(void)
 	item_kill_tree(&tree);
 }
 
+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);
+}
+
+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);
+
+	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)
+		printf("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)
+		printf("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;
+
+	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);
+
+	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);
+}
+
+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, NULL);
+	assert(node->exceptional == 0);
+
+	item_kill_tree(&tree);
+}
+
 void multiorder_checks(void)
 {
 	int i;
@@ -342,4 +627,9 @@ void multiorder_checks(void)
 	multiorder_tag_tests();
 	multiorder_iteration();
 	multiorder_tagged_iteration();
+	multiorder_join();
+	multiorder_split();
+	multiorder_account();
+
+	radix_tree_cpu_dead(0);
 }
diff --git a/tools/testing/radix-tree/rcupdate.c b/tools/testing/radix-tree/rcupdate.c
deleted file mode 100644
index 31a2d14225d6..000000000000
--- a/tools/testing/radix-tree/rcupdate.c
+++ /dev/null
@@ -1,86 +0,0 @@
-#include <linux/rcupdate.h>
-#include <pthread.h>
-#include <stdio.h>
-#include <assert.h>
-
-static pthread_mutex_t rculock = PTHREAD_MUTEX_INITIALIZER;
-static struct rcu_head *rcuhead_global = NULL;
-static __thread int nr_rcuhead = 0;
-static __thread struct rcu_head *rcuhead = NULL;
-static __thread struct rcu_head *rcutail = NULL;
-
-static pthread_cond_t rcu_worker_cond = PTHREAD_COND_INITIALIZER;
-
-/* switch to urcu implementation when it is merged. */
-void call_rcu(struct rcu_head *head, void (*func)(struct rcu_head *head))
-{
-	head->func = func;
-	head->next = rcuhead;
-	rcuhead = head;
-	if (!rcutail)
-		rcutail = head;
-	nr_rcuhead++;
-	if (nr_rcuhead >= 1000) {
-		int signal = 0;
-
-		pthread_mutex_lock(&rculock);
-		if (!rcuhead_global)
-			signal = 1;
-		rcutail->next = rcuhead_global;
-		rcuhead_global = head;
-		pthread_mutex_unlock(&rculock);
-
-		nr_rcuhead = 0;
-		rcuhead = NULL;
-		rcutail = NULL;
-
-		if (signal) {
-			pthread_cond_signal(&rcu_worker_cond);
-		}
-	}
-}
-
-static void *rcu_worker(void *arg)
-{
-	struct rcu_head *r;
-
-	rcupdate_thread_init();
-
-	while (1) {
-		pthread_mutex_lock(&rculock);
-		while (!rcuhead_global) {
-			pthread_cond_wait(&rcu_worker_cond, &rculock);
-		}
-		r = rcuhead_global;
-		rcuhead_global = NULL;
-
-		pthread_mutex_unlock(&rculock);
-
-		synchronize_rcu();
-
-		while (r) {
-			struct rcu_head *tmp = r->next;
-			r->func(r);
-			r = tmp;
-		}
-	}
-
-	rcupdate_thread_exit();
-
-	return NULL;
-}
-
-static pthread_t worker_thread;
-void rcupdate_init(void)
-{
-	pthread_create(&worker_thread, NULL, rcu_worker, NULL);
-}
-
-void rcupdate_thread_init(void)
-{
-	rcu_register_thread();
-}
-void rcupdate_thread_exit(void)
-{
-	rcu_unregister_thread();
-}
diff --git a/tools/testing/radix-tree/regression2.c b/tools/testing/radix-tree/regression2.c
index 63bf347aaf33..a41325d7a170 100644
--- a/tools/testing/radix-tree/regression2.c
+++ b/tools/testing/radix-tree/regression2.c
@@ -50,6 +50,7 @@
 #include <stdio.h>
 
 #include "regression.h"
+#include "test.h"
 
 #define PAGECACHE_TAG_DIRTY     0
 #define PAGECACHE_TAG_WRITEBACK 1
@@ -90,7 +91,7 @@ void regression2_test(void)
 	/* 1. */
 	start = 0;
 	end = max_slots - 2;
-	radix_tree_range_tag_if_tagged(&mt_tree, &start, end, 1,
+	tag_tagged_items(&mt_tree, NULL, start, end, 1,
 				PAGECACHE_TAG_DIRTY, PAGECACHE_TAG_TOWRITE);
 
 	/* 2. */
diff --git a/tools/testing/radix-tree/regression3.c b/tools/testing/radix-tree/regression3.c
index 1f06ed73d0a8..b594841fae85 100644
--- a/tools/testing/radix-tree/regression3.c
+++ b/tools/testing/radix-tree/regression3.c
@@ -5,7 +5,7 @@
  * In following radix_tree_next_slot current chunk size becomes zero.
  * This isn't checked and it tries to dereference null pointer in slot.
  *
- * Helper radix_tree_iter_next reset slot to NULL and next_index to index + 1,
+ * Helper radix_tree_iter_resume reset slot to NULL and next_index to index + 1,
  * for tagger iteraction it also must reset cached tags in iterator to abort
  * next radix_tree_next_slot and go to slow-path into radix_tree_next_chunk.
  *
@@ -88,7 +88,7 @@ void regression3_test(void)
 		printf("slot %ld %p\n", iter.index, *slot);
 		if (!iter.index) {
 			printf("next at %ld\n", iter.index);
-			slot = radix_tree_iter_next(&iter);
+			slot = radix_tree_iter_resume(slot, &iter);
 		}
 	}
 
@@ -96,7 +96,7 @@ void regression3_test(void)
 		printf("contig %ld %p\n", iter.index, *slot);
 		if (!iter.index) {
 			printf("next at %ld\n", iter.index);
-			slot = radix_tree_iter_next(&iter);
+			slot = radix_tree_iter_resume(slot, &iter);
 		}
 	}
 
@@ -106,7 +106,7 @@ void regression3_test(void)
 		printf("tagged %ld %p\n", iter.index, *slot);
 		if (!iter.index) {
 			printf("next at %ld\n", iter.index);
-			slot = radix_tree_iter_next(&iter);
+			slot = radix_tree_iter_resume(slot, &iter);
 		}
 	}
 
diff --git a/tools/testing/radix-tree/tag_check.c b/tools/testing/radix-tree/tag_check.c
index b0ac05741750..fd98c132207a 100644
--- a/tools/testing/radix-tree/tag_check.c
+++ b/tools/testing/radix-tree/tag_check.c
@@ -23,7 +23,7 @@ __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 = radix_tree_range_tag_if_tagged(tree, &first, ~0UL, 10, tag, !tag);
+	ret = tag_tagged_items(tree, NULL, first, ~0UL, 10, tag, !tag);
 	assert(ret == 1);
 	ret = item_tag_get(tree, index, !tag);
 	assert(ret != 0);
@@ -51,6 +51,7 @@ void simple_checks(void)
 	verify_tag_consistency(&tree, 1);
 	printf("before item_kill_tree: %d allocated\n", nr_allocated);
 	item_kill_tree(&tree);
+	rcu_barrier();
 	printf("after item_kill_tree: %d allocated\n", nr_allocated);
 }
 
@@ -319,10 +320,13 @@ static void single_check(void)
 	assert(ret == 0);
 	verify_tag_consistency(&tree, 0);
 	verify_tag_consistency(&tree, 1);
-	ret = radix_tree_range_tag_if_tagged(&tree, &first, 10, 10, 0, 1);
+	ret = tag_tagged_items(&tree, NULL, first, 10, 10, 0, 1);
 	assert(ret == 1);
 	ret = radix_tree_gang_lookup_tag(&tree, (void **)items, 0, BATCH, 1);
 	assert(ret == 1);
+	item_tag_clear(&tree, 0, 0);
+	ret = radix_tree_gang_lookup_tag(&tree, (void **)items, 0, BATCH, 0);
+	assert(ret == 0);
 	item_kill_tree(&tree);
 }
 
@@ -331,12 +335,16 @@ void tag_check(void)
 	single_check();
 	extend_checks();
 	contract_checks();
+	rcu_barrier();
 	printf("after extend_checks: %d allocated\n", nr_allocated);
 	__leak_check();
 	leak_check();
+	rcu_barrier();
 	printf("after leak_check: %d allocated\n", nr_allocated);
 	simple_checks();
+	rcu_barrier();
 	printf("after simple_checks: %d allocated\n", nr_allocated);
 	thrash_tags();
+	rcu_barrier();
 	printf("after thrash_tags: %d allocated\n", nr_allocated);
 }
diff --git a/tools/testing/radix-tree/test.c b/tools/testing/radix-tree/test.c
index a6e8099eaf4f..e5726e373646 100644
--- a/tools/testing/radix-tree/test.c
+++ b/tools/testing/radix-tree/test.c
@@ -24,21 +24,29 @@ int item_tag_get(struct radix_tree_root *root, unsigned long index, int tag)
 	return radix_tree_tag_get(root, index, tag);
 }
 
-int __item_insert(struct radix_tree_root *root, struct item *item,
-			unsigned order)
+int __item_insert(struct radix_tree_root *root, struct item *item)
 {
-	return __radix_tree_insert(root, item->index, order, item);
+	return __radix_tree_insert(root, item->index, item->order, item);
 }
 
 int item_insert(struct radix_tree_root *root, unsigned long index)
 {
-	return __item_insert(root, item_create(index), 0);
+	return __item_insert(root, item_create(index, 0));
 }
 
 int item_insert_order(struct radix_tree_root *root, unsigned long index,
 			unsigned order)
 {
-	return __item_insert(root, item_create(index), order);
+	return __item_insert(root, item_create(index, order));
+}
+
+void item_sanity(struct item *item, unsigned long index)
+{
+	unsigned long mask;
+	assert(!radix_tree_is_internal_node(item));
+	assert(item->order < BITS_PER_LONG);
+	mask = (1UL << item->order) - 1;
+	assert((item->index | mask) == (index | mask));
 }
 
 int item_delete(struct radix_tree_root *root, unsigned long index)
@@ -46,18 +54,19 @@ int item_delete(struct radix_tree_root *root, unsigned long index)
 	struct item *item = radix_tree_delete(root, index);
 
 	if (item) {
-		assert(item->index == index);
+		item_sanity(item, index);
 		free(item);
 		return 1;
 	}
 	return 0;
 }
 
-struct item *item_create(unsigned long index)
+struct item *item_create(unsigned long index, unsigned int order)
 {
 	struct item *ret = malloc(sizeof(*ret));
 
 	ret->index = index;
+	ret->order = order;
 	return ret;
 }
 
@@ -66,8 +75,8 @@ void item_check_present(struct radix_tree_root *root, unsigned long index)
 	struct item *item;
 
 	item = radix_tree_lookup(root, index);
-	assert(item != 0);
-	assert(item->index == index);
+	assert(item != NULL);
+	item_sanity(item, index);
 }
 
 struct item *item_lookup(struct radix_tree_root *root, unsigned long index)
@@ -80,7 +89,7 @@ void item_check_absent(struct radix_tree_root *root, unsigned long index)
 	struct item *item;
 
 	item = radix_tree_lookup(root, index);
-	assert(item == 0);
+	assert(item == NULL);
 }
 
 /*
@@ -142,6 +151,62 @@ void item_full_scan(struct radix_tree_root *root, unsigned long start,
 	assert(nfound == 0);
 }
 
+/* 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)
+{
+	unsigned long tagged = 0;
+	struct radix_tree_iter iter;
+	void **slot;
+
+	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)
+			continue;
+		slot = radix_tree_iter_resume(slot, &iter);
+		if (lock) {
+			pthread_mutex_unlock(lock);
+			rcu_barrier();
+			pthread_mutex_lock(lock);
+		}
+	}
+	if (lock)
+		pthread_mutex_unlock(lock);
+
+	return tagged;
+}
+
+/* Use the same pattern as find_swap_entry() in mm/shmem.c */
+unsigned long find_item(struct radix_tree_root *root, void *item)
+{
+	struct radix_tree_iter iter;
+	void **slot;
+	unsigned long found = -1;
+	unsigned long checked = 0;
+
+	radix_tree_for_each_slot(slot, root, &iter, 0) {
+		if (*slot == item) {
+			found = iter.index;
+			break;
+		}
+		checked++;
+		if ((checked % 4) != 0)
+			continue;
+		slot = radix_tree_iter_resume(slot, &iter);
+	}
+
+	return found;
+}
+
 static int verify_node(struct radix_tree_node *slot, unsigned int tag,
 			int tagged)
 {
@@ -200,9 +265,16 @@ void verify_tag_consistency(struct radix_tree_root *root, unsigned int tag)
 
 void item_kill_tree(struct radix_tree_root *root)
 {
+	struct radix_tree_iter iter;
+	void **slot;
 	struct item *items[32];
 	int nfound;
 
+	radix_tree_for_each_slot(slot, root, &iter, 0) {
+		if (radix_tree_exceptional_entry(*slot))
+			radix_tree_delete(root, iter.index);
+	}
+
 	while ((nfound = radix_tree_gang_lookup(root, (void **)items, 0, 32))) {
 		int i;
 
diff --git a/tools/testing/radix-tree/test.h b/tools/testing/radix-tree/test.h
index 217fb2403f09..056a23b56467 100644
--- a/tools/testing/radix-tree/test.h
+++ b/tools/testing/radix-tree/test.h
@@ -5,11 +5,11 @@
 
 struct item {
 	unsigned long index;
+	unsigned int order;
 };
 
-struct item *item_create(unsigned long index);
-int __item_insert(struct radix_tree_root *root, struct item *item,
-			unsigned order);
+struct item *item_create(unsigned long index, unsigned int order);
+int __item_insert(struct radix_tree_root *root, struct item *item);
 int item_insert(struct radix_tree_root *root, unsigned long index);
 int item_insert_order(struct radix_tree_root *root, unsigned long index,
 			unsigned order);
@@ -25,9 +25,15 @@ 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);
+unsigned long find_item(struct radix_tree_root *, void *item);
+
 void tag_check(void);
 void multiorder_checks(void);
-void iteration_test(void);
+void iteration_test(unsigned order, unsigned duration);
+void benchmark(void);
 
 struct item *
 item_tag_set(struct radix_tree_root *root, unsigned long index, int tag);
@@ -40,7 +46,14 @@ void verify_tag_consistency(struct radix_tree_root *root, unsigned int tag);
 extern int nr_allocated;
 
 /* Normally private parts of lib/radix-tree.c */
+struct radix_tree_node *entry_to_node(void *ptr);
 void radix_tree_dump(struct radix_tree_root *root);
 int root_tag_get(struct radix_tree_root *root, unsigned int tag);
 unsigned long node_maxindex(struct radix_tree_node *);
 unsigned long shift_maxindex(unsigned int shift);
+int radix_tree_cpu_dead(unsigned int cpu);
+struct radix_tree_preload {
+	unsigned nr;
+	struct radix_tree_node *nodes;
+};
+extern struct radix_tree_preload radix_tree_preloads;