Index: head/sys/compat/linuxkpi/common/include/linux/rbtree.h
===================================================================
--- head/sys/compat/linuxkpi/common/include/linux/rbtree.h
+++ head/sys/compat/linuxkpi/common/include/linux/rbtree.h
@@ -56,17 +56,11 @@
 RB_HEAD(linux_root, rb_node);
 RB_PROTOTYPE(linux_root, rb_node, __entry, panic_cmp);
 
-#define	rb_parent(r)	RB_PARENT(r, __entry)
-#define	rb_color(r)	RB_COLOR(r, __entry)
-#define	rb_is_red(r)	(rb_color(r) == RB_RED)
-#define	rb_is_black(r)	(rb_color(r) == RB_BLACK)
-#define	rb_set_parent(r, p)	rb_parent((r)) = (p)
-#define	rb_set_color(r, c)	rb_color((r)) = (c)
 #define	rb_entry(ptr, type, member)	container_of(ptr, type, member)
 
 #define RB_EMPTY_ROOT(root)     RB_EMPTY((struct linux_root *)root)
-#define RB_EMPTY_NODE(node)     (rb_parent(node) == node)
-#define RB_CLEAR_NODE(node)     (rb_set_parent(node, node))
+#define RB_EMPTY_NODE(node)     (RB_PARENT(node, __entry) == node)
+#define RB_CLEAR_NODE(node)     (RB_SET_PARENT(node, node, __entry))
 
 #define	rb_insert_color(node, root)					\
 	linux_root_RB_INSERT_COLOR((struct linux_root *)(root), (node))
@@ -81,9 +75,7 @@
 rb_link_node(struct rb_node *node, struct rb_node *parent,
     struct rb_node **rb_link)
 {
-	rb_set_parent(node, parent);
-	rb_set_color(node, RB_RED);
-	node->__entry.rbe_left = node->__entry.rbe_right = NULL;
+	RB_SET(node, parent, __entry);
 	*rb_link = node;
 }
 
@@ -91,20 +83,12 @@
 rb_replace_node(struct rb_node *victim, struct rb_node *new,
     struct rb_root *root)
 {
-	struct rb_node *p;
 
-	p = rb_parent(victim);
-	if (p) {
-		if (p->rb_left == victim)
-			p->rb_left = new;
-		else
-			p->rb_right = new;
-	} else
-		root->rb_node = new;
+	RB_SWAP_CHILD((struct linux_root *)root, victim, new, __entry);
 	if (victim->rb_left)
-		rb_set_parent(victim->rb_left, new);
+		RB_SET_PARENT(victim->rb_left, new, __entry);
 	if (victim->rb_right)
-		rb_set_parent(victim->rb_right, new);
+		RB_SET_PARENT(victim->rb_right, new, __entry);
 	*new = *victim;
 }
 
Index: head/sys/sys/tree.h
===================================================================
--- head/sys/sys/tree.h
+++ head/sys/sys/tree.h
@@ -325,8 +325,12 @@
 #define RB_ROOT(head)			(head)->rbh_root
 #define RB_EMPTY(head)			(RB_ROOT(head) == NULL)
 
+#define RB_SET_PARENT(dst, src, field) do {				\
+	RB_PARENT(dst, field) = src;					\
+} while (/*CONSTCOND*/ 0)
+
 #define RB_SET(elm, parent, field) do {					\
-	RB_PARENT(elm, field) = parent;					\
+	RB_SET_PARENT(elm, parent, field);				\
 	RB_LEFT(elm, field) = RB_RIGHT(elm, field) = NULL;		\
 	RB_COLOR(elm, field) = RB_RED;					\
 } while (/*CONSTCOND*/ 0)
@@ -344,37 +348,36 @@
 #define RB_AUGMENT(x)	break
 #endif
 
+#define RB_SWAP_CHILD(head, out, in, field) do {			\
+	if (RB_PARENT(out, field) == NULL)				\
+		RB_ROOT(head) = (in);					\
+	else if ((out) == RB_LEFT(RB_PARENT(out, field), field))	\
+		RB_LEFT(RB_PARENT(out, field), field) = (in);		\
+	else								\
+		RB_RIGHT(RB_PARENT(out, field), field) = (in);		\
+} while (/*CONSTCOND*/ 0)
+
 #define RB_ROTATE_LEFT(head, elm, tmp, field) do {			\
 	(tmp) = RB_RIGHT(elm, field);					\
 	if ((RB_RIGHT(elm, field) = RB_LEFT(tmp, field)) != NULL) {	\
-		RB_PARENT(RB_LEFT(tmp, field), field) = (elm);		\
+		RB_SET_PARENT(RB_RIGHT(elm, field), elm, field);	\
 	}								\
-	if ((RB_PARENT(tmp, field) = RB_PARENT(elm, field)) != NULL) {	\
-		if ((elm) == RB_LEFT(RB_PARENT(elm, field), field))	\
-			RB_LEFT(RB_PARENT(elm, field), field) = (tmp);	\
-		else							\
-			RB_RIGHT(RB_PARENT(elm, field), field) = (tmp);	\
-	} else								\
-		(head)->rbh_root = (tmp);				\
+	RB_SET_PARENT(tmp, RB_PARENT(elm, field), field);		\
+	RB_SWAP_CHILD(head, elm, tmp, field);				\
 	RB_LEFT(tmp, field) = (elm);					\
-	RB_PARENT(elm, field) = (tmp);					\
+	RB_SET_PARENT(elm, tmp, field);					\
 	RB_AUGMENT(elm);						\
 } while (/*CONSTCOND*/ 0)
 
 #define RB_ROTATE_RIGHT(head, elm, tmp, field) do {			\
 	(tmp) = RB_LEFT(elm, field);					\
 	if ((RB_LEFT(elm, field) = RB_RIGHT(tmp, field)) != NULL) {	\
-		RB_PARENT(RB_RIGHT(tmp, field), field) = (elm);		\
+		RB_SET_PARENT(RB_LEFT(elm, field), elm, field);		\
 	}								\
-	if ((RB_PARENT(tmp, field) = RB_PARENT(elm, field)) != NULL) {	\
-		if ((elm) == RB_LEFT(RB_PARENT(elm, field), field))	\
-			RB_LEFT(RB_PARENT(elm, field), field) = (tmp);	\
-		else							\
-			RB_RIGHT(RB_PARENT(elm, field), field) = (tmp);	\
-	} else								\
-		(head)->rbh_root = (tmp);				\
+	RB_SET_PARENT(tmp, RB_PARENT(elm, field), field);		\
+	RB_SWAP_CHILD(head, elm, tmp, field);				\
 	RB_RIGHT(tmp, field) = (elm);					\
-	RB_PARENT(elm, field) = (tmp);					\
+	RB_SET_PARENT(elm, tmp, field);					\
 	RB_AUGMENT(elm);						\
 } while (/*CONSTCOND*/ 0)
 
@@ -545,11 +548,11 @@
 attr struct type *							\
 name##_RB_REMOVE(struct name *head, struct type *elm)			\
 {									\
-	struct type *child, *old, *parent, *parent_old, *right;		\
+	struct type *child, *old, *parent, *right;			\
 	int color;							\
 									\
 	old = elm;							\
-	parent_old = parent = RB_PARENT(elm, field);			\
+	parent = RB_PARENT(elm, field);					\
 	right = RB_RIGHT(elm, field);					\
 	color = RB_COLOR(elm, field);					\
 	if (RB_LEFT(elm, field) == NULL)				\
@@ -568,20 +571,15 @@
 			child = RB_RIGHT(elm, field);			\
 			parent = RB_PARENT(elm, field);			\
 			RB_LEFT(parent, field) = child;			\
-			RB_PARENT(RB_RIGHT(old, field), field) = elm;	\
+			RB_SET_PARENT(RB_RIGHT(old, field), elm, field); \
 		}							\
-		RB_PARENT(RB_LEFT(old, field), field) = elm;		\
+		RB_SET_PARENT(RB_LEFT(old, field), elm, field);		\
 		color = RB_COLOR(elm, field);				\
 		elm->field = old->field;				\
 	}								\
-	if (parent_old == NULL)						\
-		RB_ROOT(head) = elm;					\
-	else if (RB_LEFT(parent_old, field) == old)			\
-		RB_LEFT(parent_old, field) = elm;			\
-	else								\
-		RB_RIGHT(parent_old, field) = elm;			\
+	RB_SWAP_CHILD(head, old, elm, field);				\
 	if (child != NULL) {						\
-		RB_PARENT(child, field) = parent;			\
+		RB_SET_PARENT(child, parent, field);			\
 		RB_COLOR(child, field) = RB_BLACK;			\
 	} else if (color != RB_RED && parent != NULL)			\
 		name##_RB_REMOVE_COLOR(head, parent);			\