diff options
| author | Li Zefan <lizefan@huawei.com> | 2013-06-09 17:16:46 +0800 |
|---|---|---|
| committer | Tejun Heo <tj@kernel.org> | 2013-06-13 10:48:33 -0700 |
| commit | 88fa523bff295f1d60244a54833480b02f775152 (patch) | |
| tree | 45231f9e9d1ec3612bbe3ce5d14673f27c4cbb12 /kernel | |
| parent | 5c5cc62321d9df7a9a608346fc649c4528380c8f (diff) | |
cpuset: allow to move tasks to empty cpusets
Currently some cpuset behaviors are not friendly when cpuset is co-mounted
with other cgroup controllers.
Now with this patchset if cpuset is mounted with sane_behavior option,
it behaves differently:
- Tasks will be kept in empty cpusets when hotplug happens and take
masks of ancestors with non-empty cpus/mems, instead of being moved to
an ancestor.
- A task can be moved into an empty cpuset, and again it takes masks of
ancestors, so the user can drop a task into a newly created cgroup without
having to do anything for it.
As tasks can reside in empy cpusets, here're some rules:
- They can be moved to another cpuset, regardless it's empty or not.
- Though it takes masks from ancestors, it takes other configs from the
empty cpuset.
- If the ancestors' masks are changed, those tasks will also be updated
to take new masks.
v2: add documentation in include/linux/cgroup.h
Signed-off-by: Li Zefan <lizefan@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/cpuset.c | 9 |
1 files changed, 7 insertions, 2 deletions
diff --git a/kernel/cpuset.c b/kernel/cpuset.c index 3473dd2580d1..3b3fdfdd4d78 100644 --- a/kernel/cpuset.c +++ b/kernel/cpuset.c @@ -479,7 +479,7 @@ static int validate_change(const struct cpuset *cur, const struct cpuset *trial) */ ret = -ENOSPC; if ((cgroup_task_count(cur->css.cgroup) || cur->attach_in_progress) && - (cpumask_empty(trial->cpus_allowed) || + (cpumask_empty(trial->cpus_allowed) && nodes_empty(trial->mems_allowed))) goto out; @@ -1466,8 +1466,13 @@ static int cpuset_can_attach(struct cgroup *cgrp, struct cgroup_taskset *tset) mutex_lock(&cpuset_mutex); + /* + * We allow to move tasks into an empty cpuset if sane_behavior + * flag is set. + */ ret = -ENOSPC; - if (cpumask_empty(cs->cpus_allowed) || nodes_empty(cs->mems_allowed)) + if (!cgroup_sane_behavior(cgrp) && + (cpumask_empty(cs->cpus_allowed) || nodes_empty(cs->mems_allowed))) goto out_unlock; cgroup_taskset_for_each(task, cgrp, tset) { |