Commit 7e1eb543 authored by Tejun Heo's avatar Tejun Heo
Browse files

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: default avatarTejun Heo <tj@kernel.org>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Michal Koutný <mkoutny@suse.com>
parent 026e14a2

kernel/cgroup/cgroup.c

+10 −9
Original line number Diff line number Diff line
@@ -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);