Because deletion (of the entire tree) is a relatively common use of the rbtree_postorder iteration, and because doing it safely means fiddling with temporary storage, provide a helper to simplify postorder rbtree iteration. Signed-off-by: Cody P Schafer <cody@xxxxxxxxxxxxxxxxxx> --- include/linux/rbtree.h | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/include/linux/rbtree.h b/include/linux/rbtree.h index 2879e96..64ab98b 100644 --- a/include/linux/rbtree.h +++ b/include/linux/rbtree.h @@ -85,4 +85,21 @@ static inline void rb_link_node(struct rb_node * node, struct rb_node * parent, *rb_link = node; } +/** + * rbtree_postorder_for_each_entry_safe - iterate over rb_root in post order of + * given type safe against removal of rb_node entry + * + * @pos: the 'type *' to use as a loop cursor. + * @n: another 'type *' to use as temporary storage + * @root: 'rb_root *' of the rbtree. + * @field: the name of the rb_node field within 'type'. + */ +#define rbtree_postorder_for_each_entry_safe(pos, n, root, field) \ + for (pos = rb_entry(rb_first_postorder(root), typeof(*pos), field),\ + n = rb_entry(rb_next_postorder(&pos->field), \ + typeof(*pos), field); \ + &pos->field; \ + pos = n, \ + n = rb_entry(rb_next_postorder(&pos->field), typeof(*pos), field)) + #endif /* _LINUX_RBTREE_H */ -- 1.8.3.4 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>