Re: [PATCH 2/2] cgroup: bring back kill_cnt to order css destruction

2014-02-12 Thread Hugh Dickins
On Wed, 12 Feb 2014, Tejun Heo wrote: > > Not that your implementation is bad or anything but the patch itself > somehow makes me cringe a bit. It's probably just because it has to > add to the already overly complicated offline path. Guaranteeing > strict offline ordering might be a good idea

Re: [PATCH 2/2] cgroup: bring back kill_cnt to order css destruction

2014-02-12 Thread Tejun Heo
Hello, Hugh. On Wed, Feb 12, 2014 at 03:06:26PM -0800, Hugh Dickins wrote: > Sometimes the cleanup after memcg hierarchy testing gets stuck in > mem_cgroup_reparent_charges(), unable to bring non-kmem usage down to 0. > > There may turn out to be several causes, but a major cause is this: the >

[PATCH 2/2] cgroup: bring back kill_cnt to order css destruction

2014-02-12 Thread Hugh Dickins
Sometimes the cleanup after memcg hierarchy testing gets stuck in mem_cgroup_reparent_charges(), unable to bring non-kmem usage down to 0. There may turn out to be several causes, but a major cause is this: the workitem to offline parent can get run before workitem to offline child; parent's

[PATCH 2/2] cgroup: bring back kill_cnt to order css destruction

2014-02-12 Thread Hugh Dickins
Sometimes the cleanup after memcg hierarchy testing gets stuck in mem_cgroup_reparent_charges(), unable to bring non-kmem usage down to 0. There may turn out to be several causes, but a major cause is this: the workitem to offline parent can get run before workitem to offline child; parent's

Re: [PATCH 2/2] cgroup: bring back kill_cnt to order css destruction

2014-02-12 Thread Tejun Heo
Hello, Hugh. On Wed, Feb 12, 2014 at 03:06:26PM -0800, Hugh Dickins wrote: Sometimes the cleanup after memcg hierarchy testing gets stuck in mem_cgroup_reparent_charges(), unable to bring non-kmem usage down to 0. There may turn out to be several causes, but a major cause is this: the

Re: [PATCH 2/2] cgroup: bring back kill_cnt to order css destruction

2014-02-12 Thread Hugh Dickins
On Wed, 12 Feb 2014, Tejun Heo wrote: Not that your implementation is bad or anything but the patch itself somehow makes me cringe a bit. It's probably just because it has to add to the already overly complicated offline path. Guaranteeing strict offline ordering might be a good idea but