On Mon, Jul 31, 2017 at 10:08 AM, Shaohua Li [off-list ref] wrote:

+/* Like ip6_make_flowlabel, but already has hash */
+static inline __be32 ip6_make_flowlabel_from_hash(struct net *net,
+                                                 bool autolabel, u32 hash)
+{
+       __be32 flowlabel;
+
+       if (net->ipv6.sysctl.auto_flowlabels == IP6_AUTO_FLOW_LABEL_OFF ||
+           (!autolabel &&
+            net->ipv6.sysctl.auto_flowlabels != IP6_AUTO_FLOW_LABEL_FORCED))
+               return 0;
+
+       flowlabel = (__force __be32)hash & IPV6_FLOWLABEL_MASK;
+
+       if (net->ipv6.sysctl.flowlabel_state_ranges)
+               flowlabel |= IPV6_FLOWLABEL_STATELESS_FLAG;
+
+       return flowlabel;
+}

I still don't see why you have to duplicate the code,
for me you can just refactor ip6_make_flowlabel()
and pass the hash as a parameter and pass
'flowlabel' as 0, and no run-time overhead.

Or I am missing anything?