Merge tag 'fbdev-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/tomba/linux

[firefly-linux-kernel-4.4.55.git] / include / net / cls_cgroup.h

diff --git a/include/net/cls_cgroup.h b/include/net/cls_cgroup.h
index c15d39456e146196b24bafed159099baa57e03e9..ccd6d8bffa4d8d0744c70c3591f948d6520b634a 100644 (file)
--- a/include/net/cls_cgroup.h
+++ b/include/net/cls_cgroup.h
@@ -49,9 +49,38 @@ static inline void sock_update_classid(struct sock *sk)
        if (classid != sk->sk_classid)
                sk->sk_classid = classid;
 }
+
+static inline u32 task_get_classid(const struct sk_buff *skb)
+{
+       u32 classid = task_cls_state(current)->classid;
+
+       /* Due to the nature of the classifier it is required to ignore all
+        * packets originating from softirq context as accessing `current'
+        * would lead to false results.
+        *
+        * This test assumes that all callers of dev_queue_xmit() explicitly
+        * disable bh. Knowing this, it is possible to detect softirq based
+        * calls by looking at the number of nested bh disable calls because
+        * softirqs always disables bh.
+        */
+       if (in_serving_softirq()) {
+               /* If there is an sk_classid we'll use that. */
+               if (!skb->sk)
+                       return 0;
+
+               classid = skb->sk->sk_classid;
+       }
+
+       return classid;
+}
 #else /* !CONFIG_CGROUP_NET_CLASSID */
 static inline void sock_update_classid(struct sock *sk)
 {
 }
+
+static inline u32 task_get_classid(const struct sk_buff *skb)
+{
+       return 0;
+}
 #endif /* CONFIG_CGROUP_NET_CLASSID */
 #endif  /* _NET_CLS_CGROUP_H */