cgroup: Include dying leaders with live threads in PROCS iterations
CSS_TASK_ITER_PROCS currently iterates live group leaders; however,
this means that a process with dying leader and live threads will be
skipped. IOW, cgroup.procs might be empty while cgroup.threads isn't,
which is confusing to say the least.
Fix it by making cset track dying tasks and include dying leaders with
live threads in PROCS iteration.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-and-tested-by: Topi Miettinen <toiwoton@gmail.com>
Cc: Oleg Nesterov <oleg@redhat.com>
diff --git a/include/linux/cgroup-defs.h b/include/linux/cgroup-defs.h
index 77258d2..1615b9c 100644
--- a/include/linux/cgroup-defs.h
+++ b/include/linux/cgroup-defs.h
@@ -216,6 +216,7 @@
*/
struct list_head tasks;
struct list_head mg_tasks;
+ struct list_head dying_tasks;
/* all css_task_iters currently walking this cset */
struct list_head task_iters;