cgroup: Make cgroup_get_from_id() prettier

After merging 836ac87d ("cgroup: fix cgroup_get_from_id") into for-6.1, its
combination with two commits in for-6.1 - 4534dee9 ("cgroup: cgroup: Honor
caller's cgroup NS when resolving cgroup id") and fa7e439c ("cgroup:
Homogenize cgroup_get_from_id() return value") - makes the gotos in the
error handling path too ugly while not adding anything of value.

All that the gotos are saving is one extra kernfs_put() call. Let's remove
the gotos and perform error returns directly.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Michal Koutný <mkoutny@suse.com>
This commit is contained in:
Tejun Heo 2022-09-23 07:23:06 -10:00
parent 026e14a276
commit 7e1eb5437d

View File

@ -6066,14 +6066,16 @@ void cgroup_path_from_kernfs_id(u64 id, char *buf, size_t buflen)
struct cgroup *cgroup_get_from_id(u64 id)
{
struct kernfs_node *kn;
struct cgroup *cgrp = NULL, *root_cgrp;
struct cgroup *cgrp, *root_cgrp;
kn = kernfs_find_and_get_node_by_id(cgrp_dfl_root.kf_root, id);
if (!kn)
goto out;
return ERR_PTR(-ENOENT);
if (kernfs_type(kn) != KERNFS_DIR)
goto put;
if (kernfs_type(kn) != KERNFS_DIR) {
kernfs_put(kn);
return ERR_PTR(-ENOENT);
}
rcu_read_lock();
@ -6082,21 +6084,20 @@ struct cgroup *cgroup_get_from_id(u64 id)
cgrp = NULL;
rcu_read_unlock();
put:
kernfs_put(kn);
if (!cgrp)
goto out;
return ERR_PTR(-ENOENT);
spin_lock_irq(&css_set_lock);
root_cgrp = current_cgns_cgroup_from_root(&cgrp_dfl_root);
spin_unlock_irq(&css_set_lock);
if (!cgroup_is_descendant(cgrp, root_cgrp)) {
cgroup_put(cgrp);
cgrp = NULL;
return ERR_PTR(-ENOENT);
}
out:
return cgrp ?: ERR_PTR(-ENOENT);
return cgrp;
}
EXPORT_SYMBOL_GPL(cgroup_get_from_id);