Earlier commits removed two members from struct Qdisc which places
next_sched/gso_skb into a different cacheline than ->state.
This restores the struct layout to what it was before the removal.
Move the two members, then add an annotation so they all reside in the
same cacheline.
This adds a 16 byte hole after cpu_qstats.
The hole could be closed but as it doesn't decrease total struct size just
do it this way.
Reported-by: Eric Dumazet <eduma...@google.com>
Signed-off-by: Florian Westphal <f...@strlen.de>
---
include/net/sch_generic.h | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/include/net/sch_generic.h b/include/net/sch_generic.h
index 4dedb7f..49534e2 100644
--- 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;
unsigned long state;
struct sk_buff_head q;
struct gnet_stats_basic_packed bstats;
--
2.7.3
