lkml.org 
[lkml]   [2013]   [Jul]   [30]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH 0/5] Add rbtree postorder iteration functions, runtime tests, and update zswap to use.
On Fri, Jul 26, 2013 at 02:13:38PM -0700, Cody P Schafer wrote:
> Postorder iteration yields all of a node's children prior to yielding the node
> itself, and this particular implementation also avoids examining the leaf links
> in a node after that node has been yielded.
>
> In what I expect will be it's most common usage, postorder iteration allows the

s/it's/its/

> deletion of every node in an rbtree without modifying the rbtree nodes (no
> _requirement_ that they be nulled) while avoiding referencing child nodes after
> they have been "deleted" (most commonly, freed).
>
> I have only updated zswap to use this functionality at this point, but numerous
> bits of code (most notably in the filesystem drivers) use a hand rolled
> postorder iteration that NULLs child links as it traverses the tree. Each of
> those instances could be replaced with this common implementation.

Thanks for doing this Cody! Other than the nits I've sent, it looks
good. Whole set:

Reviewed-by: Seth Jennings <sjenning@linux.vnet.ibm.com>

>
> Cody P Schafer (5):
> rbtree: add postorder iteration functions.
> rbtree: add rbtree_postorder_for_each_entry_safe() helper.
> rbtree_test: add test for postorder iteration.
> rbtree: allow tests to run as builtin
> mm/zswap: use postorder iteration when destroying rbtree
>
> include/linux/rbtree.h | 21 +++++++++++++++++++++
> lib/Kconfig.debug | 2 +-
> lib/rbtree.c | 40 ++++++++++++++++++++++++++++++++++++++++
> lib/rbtree_test.c | 12 ++++++++++++
> mm/zswap.c | 15 ++-------------
> 5 files changed, 76 insertions(+), 14 deletions(-)
>
> --
> 1.8.3.4
>



\
 
 \ /
  Last update: 2013-07-30 18:01    [W:4.009 / U:0.000 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site