docs/cgroup: add entry for cgroup.kill

Give a brief overview of the cgroup.kill functionality.

Link: https://lore.kernel.org/r/20210503143922.3093755-2-brauner@kernel.org
Cc: Roman Gushchin <guro@fb.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: cgroups@vger.kernel.org
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
This commit is contained in:
Christian Brauner 2021-05-08 14:15:39 +02:00 committed by Tejun Heo
parent 661ee62809
commit 340272b040

View File

@ -952,6 +952,21 @@ 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
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