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>

diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c
index 0d93cd1..c1f1ef6 100644 (file)
--- a/kernel/cgroup/cgroup.c
+++ b/kernel/cgroup/cgroup.c
@@ -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);