sched: place state, next_sched and gso_skb in same cacheline again

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 <edumazet@google.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Florian Westphal 2016-06-09 00:27:43 +02:00 committed by David S. Miller
parent a09ceb0e08
commit c8945043cd

View File

@ -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;