cgroup: Homogenize cgroup_get_from_id() return value

Cgroup id is user provided datum hence extend its return domain to
include possible error reason (similar to cgroup_get_from_fd()).

This change also fixes commit d4ccaf58a8 ("bpf: Introduce cgroup
iter") that would use NULL instead of proper error handling in
d4ccaf58a8 ("bpf: Introduce cgroup iter").

Additionally, neither of: fc_appid_store, bpf_iter_attach_cgroup,
mem_cgroup_get_from_ino (callers of cgroup_get_from_fd) is built without
CONFIG_CGROUPS (depends via CONFIG_BLK_CGROUP, direct, transitive
CONFIG_MEMCG respectively) transitive, so drop the singular definition
not needed with !CONFIG_CGROUPS.

Fixes: d4ccaf58a8 ("bpf: Introduce cgroup iter")
Signed-off-by: Michal Koutný <mkoutny@suse.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
This commit is contained in:
Michal Koutný
2022-08-26 18:52:37 +02:00
committed by Tejun Heo
parent 4534dee941
commit fa7e439cf9
4 changed files with 6 additions and 11 deletions

View File

@@ -750,11 +750,6 @@ static inline bool task_under_cgroup_hierarchy(struct task_struct *task,
static inline void cgroup_path_from_kernfs_id(u64 id, char *buf, size_t buflen)
{}
static inline struct cgroup *cgroup_get_from_id(u64 id)
{
return NULL;
}
#endif /* !CONFIG_CGROUPS */
#ifdef CONFIG_CGROUPS