3 files changed, 11 insertions, 26 deletions

diff --git a/drivers/md/persistent-data/Kconfig b/drivers/md/persistent-data/Kconfig
index 78c74bb71..a53cbc928 100644
--- a/drivers/md/persistent-data/Kconfig
+++ b/drivers/md/persistent-data/Kconfig
@@ -7,12 +7,3 @@ config DM_PERSISTENT_DATA
 	 Library providing immutable on-disk data structure support for
 	 device-mapper targets such as the thin provisioning target.
 
-config DM_DEBUG_BLOCK_STACK_TRACING
-       bool "Keep stack trace of persistent data block lock holders"
-       depends on STACKTRACE_SUPPORT && DM_PERSISTENT_DATA
-       select STACKTRACE
-       ---help---
-	 Enable this for messages that may help debug problems with the
-	 block manager locking used by thin provisioning and caching.
-
-	 If unsure, say N.
diff --git a/drivers/md/persistent-data/dm-block-manager.c b/drivers/md/persistent-data/dm-block-manager.c
index f2393ba83..1e33dd51c 100644
--- a/drivers/md/persistent-data/dm-block-manager.c
+++ b/drivers/md/persistent-data/dm-block-manager.c
@@ -97,10 +97,6 @@ static void __del_holder(struct block_lock *lock, struct task_struct *task)
 static int __check_holder(struct block_lock *lock)
 {
 	unsigned i;
-#ifdef CONFIG_DM_DEBUG_BLOCK_STACK_TRACING
-	static struct stack_trace t;
-	static stack_entries entries;
-#endif
 
 	for (i = 0; i < MAX_HOLDERS; i++) {
 		if (lock->holders[i] == current) {
@@ -110,12 +106,7 @@ static int __check_holder(struct block_lock *lock)
 			print_stack_trace(lock->traces + i, 4);
 
 			DMERR("subsequent acquisition attempted here:");
-			t.nr_entries = 0;
-			t.max_entries = MAX_STACK;
-			t.entries = entries;
-			t.skip = 3;
-			save_stack_trace(&t);
-			print_stack_trace(&t, 4);
+			dump_stack();
 #endif
 			return -EINVAL;
 		}
diff --git a/drivers/md/persistent-data/dm-btree.c b/drivers/md/persistent-data/dm-btree.c
index b1ced58eb..ea3d3b656 100644
--- a/drivers/md/persistent-data/dm-btree.c
+++ b/drivers/md/persistent-data/dm-btree.c
@@ -754,12 +754,19 @@ static int btree_insert_raw(struct shadow_spine *s, dm_block_t root,
 	return 0;
 }
 
+static bool need_insert(struct btree_node *node, uint64_t *keys,
+			unsigned level, unsigned index)
+{
+        return ((index >= le32_to_cpu(node->header.nr_entries)) ||
+		(le64_to_cpu(node->keys[index]) != keys[level]));
+}
+
 static int insert(struct dm_btree_info *info, dm_block_t root,
 		  uint64_t *keys, void *value, dm_block_t *new_root,
 		  int *inserted)
 		  __dm_written_to_disk(value)
 {
-	int r, need_insert;
+	int r;
 	unsigned level, index = -1, last_level = info->levels - 1;
 	dm_block_t block = root;
 	struct shadow_spine spine;
@@ -775,10 +782,8 @@ static int insert(struct dm_btree_info *info, dm_block_t root,
 			goto bad;
 
 		n = dm_block_data(shadow_current(&spine));
-		need_insert = ((index >= le32_to_cpu(n->header.nr_entries)) ||
-			       (le64_to_cpu(n->keys[index]) != keys[level]));
 
-		if (need_insert) {
+		if (need_insert(n, keys, level, index)) {
 			dm_block_t new_tree;
 			__le64 new_le;
 
@@ -805,10 +810,8 @@ static int insert(struct dm_btree_info *info, dm_block_t root,
 		goto bad;
 
 	n = dm_block_data(shadow_current(&spine));
-	need_insert = ((index >= le32_to_cpu(n->header.nr_entries)) ||
-		       (le64_to_cpu(n->keys[index]) != keys[level]));
 
-	if (need_insert) {
+	if (need_insert(n, keys, level, index)) {
 		if (inserted)
 			*inserted = 1;