cgroup: warn about broken hierarchies only after css_online

If everything goes right, it shouldn't really matter if we are spitting
this warning after css_alloc or css_online. If we fail between then,
there are some ill cases where we would previously see the message and
now we won't (like if the files fail to be created).

I believe it really shouldn't matter: this message is intended in spirit
to be shown when creation succeeds, but with insane settings.

Signed-off-by: Glauber Costa <glommer@parallels.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
This commit is contained in:
Glauber Costa 2012-11-30 17:31:23 +04:00 committed by Tejun Heo
parent 9718ceb343
commit 1f869e8711

View File

@ -4151,15 +4151,6 @@ static long cgroup_create(struct cgroup *parent, struct dentry *dentry,
if (err)
goto err_free_all;
}
if (ss->broken_hierarchy && !ss->warned_broken_hierarchy &&
parent->parent) {
pr_warning("cgroup: %s (%d) created nested cgroup for controller \"%s\" which has incomplete hierarchy support. Nested cgroups may change behavior in the future.\n",
current->comm, current->pid, ss->name);
if (!strcmp(ss->name, "memory"))
pr_warning("cgroup: \"memory\" requires setting use_hierarchy to 1 on the root.\n");
ss->warned_broken_hierarchy = true;
}
}
/*
@ -4188,6 +4179,15 @@ static long cgroup_create(struct cgroup *parent, struct dentry *dentry,
err = online_css(ss, cgrp);
if (err)
goto err_destroy;
if (ss->broken_hierarchy && !ss->warned_broken_hierarchy &&
parent->parent) {
pr_warning("cgroup: %s (%d) created nested cgroup for controller \"%s\" which has incomplete hierarchy support. Nested cgroups may change behavior in the future.\n",
current->comm, current->pid, ss->name);
if (!strcmp(ss->name, "memory"))
pr_warning("cgroup: \"memory\" requires setting use_hierarchy to 1 on the root.\n");
ss->warned_broken_hierarchy = true;
}
}
err = cgroup_populate_dir(cgrp, true, root->subsys_mask);