9 Sep
2025
9 Sep
'25
12:04 p.m.
Hi Arun,
On 09.09.25 11:56, Arunpravin Paneer Selvam wrote: [SNIP]
+/**
- rbtree_for_each_entry_safe - iterate in-order over rb_root safe against removal
- @pos: the 'type *' to use as a loop cursor
- @n: another 'type *' to use as temporary storage
- @root: 'rb_root *' of the rbtree
- @member: the name of the rb_node field within 'type'
- */
+#define rbtree_for_each_entry_safe(pos, n, root, member) \
- for ((pos) = rb_entry_safe(rb_first(root), typeof(*(pos)), member), \
(n) = (pos) ? rb_entry_safe(rb_next(&(pos)->member), typeof(*(pos)), member) : NULL; \(pos); \(pos) = (n), \(n) = (pos) ? rb_entry_safe(rb_next(&(pos)->member), typeof(*(pos)), member) : NULL)
As far as I know exactly that operation does not work on an R/B tree.
See the _safe() variants of the for_each_ macros are usually used to iterate over a container while being able to remove entries.
But because of the potential re-balance storing just the next entry is not sufficient for an R/B tree to do that as far as I know.
Please explain how exactly you want to use this macro.
Regards, Christian.
+/**
- rbtree_reverse_for_each_entry_safe - iterate in reverse in-order over rb_root
- safe against removal
- @pos: the struct type * to use as a loop cursor.
- @n: another struct type * to use as temporary storage.
- @root: pointer to struct rb_root to iterate.
- @member: name of the rb_node field within the struct.
- */
+#define rbtree_reverse_for_each_entry_safe(pos, n, root, member) \
- for ((pos) = rb_entry_safe(rb_last(root), typeof(*(pos)), member), \
(n) = (pos) ? rb_entry_safe(rb_prev(&(pos)->member), typeof(*(pos)), member) : NULL; \(pos); \(pos) = (n), \(n) = (pos) ? rb_entry_safe(rb_prev(&(pos)->member), typeof(*(pos)), member) : NULL)/**
- rbtree_postorder_for_each_entry_safe - iterate in post-order over rb_root of
- given type allowing the backing memory of @pos to be invalidated
base-commit: 7156602d56e5ad689ae11e03680ab6326238b5e3