* [PATCH cgroup/for-3.12-fixes] cgroup: fix cgroup post-order descendant walk of empty subtree
@ 2013-09-06 19:31 Tejun Heo
[not found] ` <20130906193108.GH22763-9pTldWuhBndy/B6EtB590w@public.gmane.org>
0 siblings, 1 reply; 6+ messages in thread
From: Tejun Heo @ 2013-09-06 19:31 UTC (permalink / raw)
To: Li Zefan
Cc: containers-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA,
cgroups-u79uwXL29TY76Z2rM5mHXA
bd8815a6d8 ("cgroup: make css_for_each_descendant() and friends
include the origin css in the iteration") updated cgroup descendant
iterators to include the origin css; unfortuantely, it forgot to drop
special case handling in css_next_descendant_post() for empty subtree
leading to failure to visit the origin css without any child.
Fix it by dropping the special case handling and always returning the
leftmost descendant on the first iteration.
Signed-off-by: Tejun Heo <tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
---
kernel/cgroup.c | 8 +++-----
1 file changed, 3 insertions(+), 5 deletions(-)
diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index e0aeb32..8075b72 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -3187,11 +3187,9 @@ css_next_descendant_post(struct cgroup_subsys_state *pos,
WARN_ON_ONCE(!rcu_read_lock_held());
- /* if first iteration, visit the leftmost descendant */
- if (!pos) {
- next = css_leftmost_descendant(root);
- return next != root ? next : NULL;
- }
+ /* if first iteration, visit leftmost descendant which may be @root */
+ if (!pos)
+ return css_leftmost_descendant(root);
/* if we visited @root, we're done */
if (pos == root)
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH cgroup/for-3.12-fixes] cgroup: fix cgroup post-order descendant walk of empty subtree
@ 2013-09-06 19:31 Tejun Heo
0 siblings, 0 replies; 6+ messages in thread
From: Tejun Heo @ 2013-09-06 19:31 UTC (permalink / raw)
To: Li Zefan
Cc: cgroups-u79uwXL29TY76Z2rM5mHXA,
containers-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA
bd8815a6d8 ("cgroup: make css_for_each_descendant() and friends
include the origin css in the iteration") updated cgroup descendant
iterators to include the origin css; unfortuantely, it forgot to drop
special case handling in css_next_descendant_post() for empty subtree
leading to failure to visit the origin css without any child.
Fix it by dropping the special case handling and always returning the
leftmost descendant on the first iteration.
Signed-off-by: Tejun Heo <tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
---
kernel/cgroup.c | 8 +++-----
1 file changed, 3 insertions(+), 5 deletions(-)
diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index e0aeb32..8075b72 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -3187,11 +3187,9 @@ css_next_descendant_post(struct cgroup_subsys_state *pos,
WARN_ON_ONCE(!rcu_read_lock_held());
- /* if first iteration, visit the leftmost descendant */
- if (!pos) {
- next = css_leftmost_descendant(root);
- return next != root ? next : NULL;
- }
+ /* if first iteration, visit leftmost descendant which may be @root */
+ if (!pos)
+ return css_leftmost_descendant(root);
/* if we visited @root, we're done */
if (pos == root)
^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH cgroup/for-3.12-fixes] cgroup: fix cgroup post-order descendant walk of empty subtree
[not found] ` <20130906193108.GH22763-9pTldWuhBndy/B6EtB590w@public.gmane.org>
2013-09-10 9:19 ` Li Zefan
@ 2013-09-10 9:19 ` Li Zefan
2013-09-10 13:41 ` Tejun Heo
2013-09-10 13:41 ` Tejun Heo
3 siblings, 0 replies; 6+ messages in thread
From: Li Zefan @ 2013-09-10 9:19 UTC (permalink / raw)
To: Tejun Heo
Cc: containers-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA,
cgroups-u79uwXL29TY76Z2rM5mHXA
On 2013/9/7 3:31, Tejun Heo wrote:
> bd8815a6d8 ("cgroup: make css_for_each_descendant() and friends
> include the origin css in the iteration") updated cgroup descendant
> iterators to include the origin css; unfortuantely, it forgot to drop
> special case handling in css_next_descendant_post() for empty subtree
> leading to failure to visit the origin css without any child.
>
> Fix it by dropping the special case handling and always returning the
> leftmost descendant on the first iteration.
>
> Signed-off-by: Tejun Heo <tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
Acked-by: Li Zefan <lizefan-hv44wF8Li93QT0dZR+AlfA@public.gmane.org>
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH cgroup/for-3.12-fixes] cgroup: fix cgroup post-order descendant walk of empty subtree
[not found] ` <20130906193108.GH22763-9pTldWuhBndy/B6EtB590w@public.gmane.org>
@ 2013-09-10 9:19 ` Li Zefan
2013-09-10 9:19 ` Li Zefan
` (2 subsequent siblings)
3 siblings, 0 replies; 6+ messages in thread
From: Li Zefan @ 2013-09-10 9:19 UTC (permalink / raw)
To: Tejun Heo
Cc: cgroups-u79uwXL29TY76Z2rM5mHXA,
containers-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA
On 2013/9/7 3:31, Tejun Heo wrote:
> bd8815a6d8 ("cgroup: make css_for_each_descendant() and friends
> include the origin css in the iteration") updated cgroup descendant
> iterators to include the origin css; unfortuantely, it forgot to drop
> special case handling in css_next_descendant_post() for empty subtree
> leading to failure to visit the origin css without any child.
>
> Fix it by dropping the special case handling and always returning the
> leftmost descendant on the first iteration.
>
> Signed-off-by: Tejun Heo <tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
Acked-by: Li Zefan <lizefan-hv44wF8Li93QT0dZR+AlfA@public.gmane.org>
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH cgroup/for-3.12-fixes] cgroup: fix cgroup post-order descendant walk of empty subtree
[not found] ` <20130906193108.GH22763-9pTldWuhBndy/B6EtB590w@public.gmane.org>
2013-09-10 9:19 ` Li Zefan
2013-09-10 9:19 ` Li Zefan
@ 2013-09-10 13:41 ` Tejun Heo
2013-09-10 13:41 ` Tejun Heo
3 siblings, 0 replies; 6+ messages in thread
From: Tejun Heo @ 2013-09-10 13:41 UTC (permalink / raw)
To: Li Zefan
Cc: containers-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA,
cgroups-u79uwXL29TY76Z2rM5mHXA
On Fri, Sep 06, 2013 at 03:31:08PM -0400, Tejun Heo wrote:
> bd8815a6d8 ("cgroup: make css_for_each_descendant() and friends
> include the origin css in the iteration") updated cgroup descendant
> iterators to include the origin css; unfortuantely, it forgot to drop
> special case handling in css_next_descendant_post() for empty subtree
> leading to failure to visit the origin css without any child.
>
> Fix it by dropping the special case handling and always returning the
> leftmost descendant on the first iteration.
>
> Signed-off-by: Tejun Heo <tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
Applied to cgroup/for-3.12-fixes.
Thanks.
--
tejun
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH cgroup/for-3.12-fixes] cgroup: fix cgroup post-order descendant walk of empty subtree
[not found] ` <20130906193108.GH22763-9pTldWuhBndy/B6EtB590w@public.gmane.org>
` (2 preceding siblings ...)
2013-09-10 13:41 ` Tejun Heo
@ 2013-09-10 13:41 ` Tejun Heo
3 siblings, 0 replies; 6+ messages in thread
From: Tejun Heo @ 2013-09-10 13:41 UTC (permalink / raw)
To: Li Zefan
Cc: cgroups-u79uwXL29TY76Z2rM5mHXA,
containers-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA
On Fri, Sep 06, 2013 at 03:31:08PM -0400, Tejun Heo wrote:
> bd8815a6d8 ("cgroup: make css_for_each_descendant() and friends
> include the origin css in the iteration") updated cgroup descendant
> iterators to include the origin css; unfortuantely, it forgot to drop
> special case handling in css_next_descendant_post() for empty subtree
> leading to failure to visit the origin css without any child.
>
> Fix it by dropping the special case handling and always returning the
> leftmost descendant on the first iteration.
>
> Signed-off-by: Tejun Heo <tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
Applied to cgroup/for-3.12-fixes.
Thanks.
--
tejun
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2013-09-10 13:41 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2013-09-06 19:31 [PATCH cgroup/for-3.12-fixes] cgroup: fix cgroup post-order descendant walk of empty subtree Tejun Heo
[not found] ` <20130906193108.GH22763-9pTldWuhBndy/B6EtB590w@public.gmane.org>
2013-09-10 9:19 ` Li Zefan
2013-09-10 9:19 ` Li Zefan
2013-09-10 13:41 ` Tejun Heo
2013-09-10 13:41 ` Tejun Heo
-- strict thread matches above, loose matches on Subject: below --
2013-09-06 19:31 Tejun Heo
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.