timers: Add rb_init_node() to allow for stack allocated rb nodes

In cases where a timerqueue_node or some structure that utilizes a timerqueue_node is allocated on the stack, gcc would give warnings caused by the timerqueue_init()'s calling RB_CLEAR_NODE, which self-references the nodes uninitialized data. The solution is to create an rb_init_node() function that zeros the rb_node structure out and then calls RB_CLEAR_NODE(), and then call the new init function from timerqueue_init(). CC: Thomas Gleixner <tglx@linutronix.de> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: John Stultz <john.stultz@linaro.org>

timers: Add rb_init_node() to allow for stack allocated rb nodes
In cases where a timerqueue_node or some structure that utilizes a timerqueue_node is allocated on the stack, gcc would give warnings caused by the timerqueue_init()'s calling RB_CLEAR_NODE, which self-references the nodes uninitialized data. The solution is to create an rb_init_node() function that zeros the rb_node structure out and then calls RB_CLEAR_NODE(), and then call the new init function from timerqueue_init(). CC: Thomas Gleixner <tglx@linutronix.de> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: John Stultz <john.stultz@linaro.org>
John Stultz
1 parent 304529b1b6
Showing 2 changed files with 9 additions and 1 deletions Side-by-side Diff
include/linux/rbtree.h
include/linux/timerqueue.h
@@ -136,6 +136,14 @@
 #define RB_EMPTY_NODE(node)	(rb_parent(node) == node)
 #define RB_CLEAR_NODE(node)	(rb_set_parent(node, node))
  
+static inline void rb_init_node(struct rb_node *rb)
+{
+	rb->rb_parent_color = 0;
+	rb->rb_right = NULL;
+	rb->rb_left = NULL;
+	RB_CLEAR_NODE(rb);
+}
+
 extern void rb_insert_color(struct rb_node *, struct rb_root *);
 extern void rb_erase(struct rb_node *, struct rb_root *);
  
@@ -39,7 +39,7 @@
  
 static inline void timerqueue_init(struct timerqueue_node *node)
 {
-	RB_CLEAR_NODE(&node->node);
+	rb_init_node(&node->node);
 }
  
 static inline void timerqueue_init_head(struct timerqueue_head *head)
...	...	@@ -136,6 +136,14 @@
136	136	#define RB_EMPTY_NODE(node) (rb_parent(node) == node)
137	137	#define RB_CLEAR_NODE(node) (rb_set_parent(node, node))
138	138
	139	+static inline void rb_init_node(struct rb_node *rb)
	140	+{
	141	+ rb->rb_parent_color = 0;
	142	+ rb->rb_right = NULL;
	143	+ rb->rb_left = NULL;
	144	+ RB_CLEAR_NODE(rb);
	145	+}
	146	+
139	147	extern void rb_insert_color(struct rb_node , struct rb_root );
140	148	extern void rb_erase(struct rb_node , struct rb_root );
141	149
...	...	@@ -39,7 +39,7 @@
39	39
40	40	static inline void timerqueue_init(struct timerqueue_node *node)
41	41	{
42		- RB_CLEAR_NODE(&node->node);
	42	+ rb_init_node(&node->node);
43	43	}
44	44
45	45	static inline void timerqueue_init_head(struct timerqueue_head *head)