[PATCH] cgroup: Properly init nr_tasks in cgroup_taskset

Waiman Long
2017-09-14T20:45:13Z

Commit 610467270fb3 ("cgroup: don't call migration methods if there
are no tasks to migrate") introduces a new field nr_tasks to the
cgroup_taskset structure for keeping track of the number of tasks
contained in the structure. The initial value of this field, however,
is not guaranteed to be 0 as all the cgroup_taskset structures are
allocated from stack. Therefore, we need to explicitly initilized
it in the CGROUP_TASKSET_INIT() macro for the new code to behave
correctly.

Signed-off-by: Waiman Long <longman-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
---
kernel/cgroup/cgroup-internal.h | 1 +
1 file changed, 1 insertion(+)

diff --git a/kernel/cgroup/cgroup-internal.h b/kernel/cgroup/cgroup-internal.h
index 5151ff2..6b4c04e 100644
--- a/kernel/cgroup/cgroup-internal.h
+++ b/kernel/cgroup/cgroup-internal.h
@@ -76,6 +76,7 @@ struct cgroup_mgctx {
.src_csets = LIST_HEAD_INIT(tset.src_csets), \
.dst_csets = LIST_HEAD_INIT(tset.dst_csets), \
.csets = &tset.src_csets, \
+ .nr_tasks = 0, \
}

#define CGROUP_MGCTX_INIT(name) \
--
1.8.3.1