From: Christian Brauner <christian.brauner@xxxxxxxxxx>
Give a brief overview of the cgroup.kill functionality.
Cc: Roman Gushchin <guro@xxxxxx>
Cc: Tejun Heo <tj@xxxxxxxxxx>
Cc: cgroups@xxxxxxxxxxxxxxx
Signed-off-by: Christian Brauner <christian.brauner@xxxxxxxxxx>
---
/* v2 */
- Roman Gushchin <guro@xxxxxx>:
- Drop sentence that mentions combined useage of cgroup.kill and
cgroup.freezer.
---
Documentation/admin-guide/cgroup-v2.rst | 15 +++++++++++++++
1 file changed, 15 insertions(+)
diff --git a/Documentation/admin-guide/cgroup-v2.rst b/Documentation/admin-guide/cgroup-v2.rst
index 64c62b979f2f..6adc749d863e 100644
--- a/Documentation/admin-guide/cgroup-v2.rst
+++ b/Documentation/admin-guide/cgroup-v2.rst
@@ -949,6 +949,21 @@ All cgroup core files are prefixed with "cgroup."
it's possible to delete a frozen (and empty) cgroup, as well as
create new sub-cgroups.
+ cgroup.kill
+ A write-only single value file which exists in non-root cgroups.
+ The only allowed value is "1".
+
+ Writing "1" to the file causes the cgroup and all descendant cgroups to
+ be killed. This means that all processes located in the affected cgroup
+ tree will be killed via SIGKILL.
+
+ Killing a cgroup tree will deal with concurrent forks appropriately and
+ is protected against migrations.
+
+ In a threaded cgroup, writing this file fails with EOPNOTSUPP as
+ killing cgroups is a process directed operation, i.e. it affects
+ the whole thread-group.
+
Controllers
===========
--
2.27.0
