summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
-rw-r--r--kernel/cpuset.c19
1 files changed, 11 insertions, 8 deletions
diff --git a/kernel/cpuset.c b/kernel/cpuset.c
index 2b93b50cbe4b..026faccca869 100644
--- a/kernel/cpuset.c
+++ b/kernel/cpuset.c
@@ -1342,19 +1342,22 @@ static int cpuset_can_attach(struct cgroup_subsys *ss,
struct cgroup *cont, struct task_struct *tsk)
{
struct cpuset *cs = cgroup_cs(cont);
- int ret = 0;
if (cpumask_empty(cs->cpus_allowed) || nodes_empty(cs->mems_allowed))
return -ENOSPC;
- if (tsk->flags & PF_THREAD_BOUND) {
- mutex_lock(&callback_mutex);
- if (!cpumask_equal(&tsk->cpus_allowed, cs->cpus_allowed))
- ret = -EINVAL;
- mutex_unlock(&callback_mutex);
- }
+ /*
+ * Kthreads bound to specific cpus cannot be moved to a new cpuset; we
+ * cannot change their cpu affinity and isolating such threads by their
+ * set of allowed nodes is unnecessary. Thus, cpusets are not
+ * applicable for such threads. This prevents checking for success of
+ * set_cpus_allowed_ptr() on all attached tasks before cpus_allowed may
+ * be changed.
+ */
+ if (tsk->flags & PF_THREAD_BOUND)
+ return -EINVAL;
- return ret < 0 ? ret : security_task_setscheduler(tsk, 0, NULL);
+ return security_task_setscheduler(tsk, 0, NULL);
}
static void cpuset_attach(struct cgroup_subsys *ss,