From 7e1eb5437d3c3fdb61d45378579aab383cafc694 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Fri, 23 Sep 2022 07:23:06 -1000 Subject: [PATCH] cgroup: Make cgroup_get_from_id() prettier MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit 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 Cc: Ming Lei Cc: Michal Koutný --- kernel/cgroup/cgroup.c | 19 ++++++++++--------- 1 file changed, 10 insertions(+), 9 deletions(-) diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c index 0d93cd17..c1f1ef6 100644 --- 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); -- 2.7.4