cgroup: net_cls: Do not define task_cls_classid() when not selected

task_cls_classid() should not be defined in case the configuration is
CONFIG_NET_CLS_CGROUP=n. The reason is that in a following patch the
net_cls_subsys_id will only be defined if CONFIG_NET_CLS_CGROUP!=n.
When net_cls is not built at all a callee should only get an empty
task_cls_classid() without any references to net_cls_subsys_id.

Signed-off-by: Daniel Wagner <daniel.wagner@bmw-carit.de>
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Cc: Gao feng <gaofeng@cn.fujitsu.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: John Fastabend <john.r.fastabend@intel.com>
Cc: netdev@vger.kernel.org
Cc: cgroups@vger.kernel.org

1 files changed, 2 insertions, 0 deletions

diff --git a/net/core/sock.c b/net/core/sock.c
index 8f67ced8d6a8..82cadc62a872 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -1223,6 +1223,7 @@ static void sk_prot_free(struct proto *prot, struct sock *sk)
 }
 
 #ifdef CONFIG_CGROUPS
+#if IS_ENABLED(CONFIG_NET_CLS_CGROUP)
 void sock_update_classid(struct sock *sk)
 {
         u32 classid;
@@ -1234,6 +1235,7 @@ void sock_update_classid(struct sock *sk)
                 sk->sk_classid = classid;
 }
 EXPORT_SYMBOL(sock_update_classid);
+#endif
 
 void sock_update_netprioidx(struct sock *sk, struct task_struct *task)
 {