forge/linux-pinenote
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

rbtree: add rbtree_postorder_for_each_entry_safe() helper

Browse source 
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@linux.vnet.ibm.com>
Reviewed-by: Seth Jennings <sjenning@linux.vnet.ibm.com>
Cc: David Woodhouse <David.Woodhouse@intel.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Michel Lespinasse <walken@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Cody P Schafer 2013-09-11 14:25:11 -07:00 • committed by Linus Torvalds
commit 2b52908925
1 changed files with 18 additions and 0 deletions
Download patch file Download diff file Expand all files Collapse all files

18
include/linux/rbtree.h
View file

@ -85,4 +85,22 @@ static inline void rb_link_node(struct rb_node * node, struct rb_node * parent,
*rb_link = node; *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 */ #endif /* _LINUX_RBTREE_H */