Re: [PATCH -next 3/4] sched: remove qdisc_rehape_fail

Would you mind an annotation rather than covering the hole?

--- a/include/net/sch_generic.h
+++ b/include/net/sch_generic.h

@@ -71,11 +71,11 @@ struct Qdisc {
        struct gnet_stats_basic_cpu __percpu *cpu_bstats;
        struct gnet_stats_queue __percpu *cpu_qstats;
 
-       struct Qdisc            *next_sched;
-       struct sk_buff          *gso_skb;
        /*
         * For performance sake on SMP, we put highly modified fields at the end
         */
+       struct Qdisc            *next_sched ____cacheline_aligned_in_smp;
+       struct sk_buff          *gso_skb;

... it creates 16 byte hole after cpu_qstats and keeps the rest as-is
 (i.e. next_sched is at beginning of 2nd cacheline, as before the removal).

I could also cover the hole by moving rcu_head there but it seems fragile
and doesn't reduce total struct size anyway (we get larger hole at end).

If you have no objection I'd resubmit the series as-is but with this patch.

Let me know, thanks Eric!