cgroupfs: create /sys/fs/cgroup to mount cgroupfs on
We really shouldn't be asking userspace to create new root filesystems.
So follow along with all of the other in-kernel filesystems, and provide
a mount point in sysfs.
For cgroupfs, this should be in /sys/fs/cgroup/ This change provides
that mount point when the cgroup filesystem is registered in the kernel.
Acked-by: Paul Menage <menage@google.com>
Acked-by: Dhaval Giani <dhaval.giani@gmail.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Lennart Poettering <lennart@poettering.net>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index a8ce099..d83cab0 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -1623,6 +1623,8 @@
.kill_sb = cgroup_kill_sb,
};
+static struct kobject *cgroup_kobj;
+
static inline struct cgroup *__d_cgrp(struct dentry *dentry)
{
return dentry->d_fsdata;
@@ -3894,9 +3896,18 @@
hhead = css_set_hash(init_css_set.subsys);
hlist_add_head(&init_css_set.hlist, hhead);
BUG_ON(!init_root_id(&rootnode));
- err = register_filesystem(&cgroup_fs_type);
- if (err < 0)
+
+ cgroup_kobj = kobject_create_and_add("cgroup", fs_kobj);
+ if (!cgroup_kobj) {
+ err = -ENOMEM;
goto out;
+ }
+
+ err = register_filesystem(&cgroup_fs_type);
+ if (err < 0) {
+ kobject_put(cgroup_kobj);
+ goto out;
+ }
proc_create("cgroups", 0, NULL, &proc_cgroupstats_operations);