[PATCH v2 01/29] radix-tree: Introduce radix_tree_empty

Matthew Wilcox
2016-04-14T14:17:36Z

The irqdomain code was checking for 0 or 1 entries, not 0 entries like
the comment said they were. Introduce a new helper that will actually
check for an empty tree.

Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com>
---
include/linux/radix-tree.h | 5 +++++
kernel/irq/irqdomain.c | 7 +------
2 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/include/linux/radix-tree.h b/include/linux/radix-tree.h
index 51a97ac..83f708e 100644
--- a/include/linux/radix-tree.h
+++ b/include/linux/radix-tree.h
@@ -136,6 +136,11 @@ do { \
(root)->rnode = NULL; \
} while (0)

+static inline bool radix_tree_empty(struct radix_tree_root *root)
+{
+ return root->rnode == NULL;
+}
+
/**
* Radix-tree synchronization
*
diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c
index 3a519a0..ba3f60d 100644
--- a/kernel/irq/irqdomain.c
+++ b/kernel/irq/irqdomain.c
@@ -139,12 +139,7 @@ void irq_domain_remove(struct irq_domain *domain)
{
mutex_lock(&irq_domain_mutex);

- /*
- * radix_tree_delete() takes care of destroying the root
- * node when all entries are removed. Shout if there are
- * any mappings left.
- */
- WARN_ON(domain->revmap_tree.height);
+ WARN_ON(!radix_tree_empty(&domain->revmap_tree));

list_del(&domain->link);

--
2.8.0.rc3