From mboxrd@z Thu Jan 1 00:00:00 1970 From: Waiman Long Subject: [PATCH] cgroup: Show control files in cgroup2 root after mount Date: Tue, 18 Jul 2017 15:32:16 -0400 Message-ID: <1500406336-29512-1-git-send-email-longman@redhat.com> Return-path: DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.redhat.com 19762C04D2A4 Sender: cgroups-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Tejun Heo , Li Zefan , Johannes Weiner Cc: cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Waiman Long It was found that when a cgroup2 filesystem was mounted, control files other than the base cgroup.* ones were not shown in the root directory. They were shown only after some controllers were activated in the root's cgroup.subtree_control file. This was caused by a lack of the kernfs_activate() call which was fixed by this patch. Signed-off-by: Waiman Long --- kernel/cgroup/cgroup.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c index 89a23c6..fb1893b 100644 --- a/kernel/cgroup/cgroup.c +++ b/kernel/cgroup/cgroup.c @@ -2024,8 +2024,10 @@ static struct dentry *cgroup_mount(struct file_system_type *fs_type, dentry = cgroup_do_mount(&cgroup2_fs_type, flags, &cgrp_dfl_root, CGROUP2_SUPER_MAGIC, ns); - if (!IS_ERR(dentry)) + if (!IS_ERR(dentry)) { apply_cgroup_root_flags(root_flags); + kernfs_activate(cgrp_dfl_root.cgrp.kn); + } } else { dentry = cgroup1_mount(&cgroup_fs_type, flags, data, CGROUP_SUPER_MAGIC, ns); -- 1.8.3.1