From: Honglei Wang honglei.wang@oracle.com
[ Upstream commit 742e8cd3e1ba6f19cad6d912f8d469df5557d0fd ]
It's not necessary to adjust the task state and revisit the state of source and destination cgroups if the cgroups are not in freeze state and the task itself is not frozen.
And in this scenario, it wakes up the task who's not supposed to be ready to run.
Don't do the unnecessary task state adjustment can help stop waking up the task without a reason.
Signed-off-by: Honglei Wang honglei.wang@oracle.com Acked-by: Roman Gushchin guro@fb.com Signed-off-by: Tejun Heo tj@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- kernel/cgroup/freezer.c | 9 +++++++++ 1 file changed, 9 insertions(+)
diff --git a/kernel/cgroup/freezer.c b/kernel/cgroup/freezer.c index 8cf010680678..3984dd6b8ddb 100644 --- a/kernel/cgroup/freezer.c +++ b/kernel/cgroup/freezer.c @@ -230,6 +230,15 @@ void cgroup_freezer_migrate_task(struct task_struct *task, if (task->flags & PF_KTHREAD) return;
+ /* + * It's not necessary to do changes if both of the src and dst cgroups + * are not freezing and task is not frozen. + */ + if (!test_bit(CGRP_FREEZE, &src->flags) && + !test_bit(CGRP_FREEZE, &dst->flags) && + !task->frozen) + return; + /* * Adjust counters of freezing and frozen tasks. * Note, that if the task is frozen, but the destination cgroup is not