net: shrink struct softnet_data

flow_limit in struct softnet_data is only read from local cpu
and can be moved to fill a hole, reducing softnet_data size by
64 bytes on x86_64

While we are at it, move output_queue, output_queue_tailp and
completion_queue, so that rx / tx paths touch a single cache line.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet 2014-11-02 06:00:12 -08:00 коммит произвёл David S. Miller
Родитель 55b42b5ca2
Коммит 4cdb1e2e3d
1 изменённых файлов: 8 добавлений и 7 удалений

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@ -2329,10 +2329,7 @@ extern int netdev_flow_limit_table_len;
* Incoming packets are placed on per-cpu queues
*/
struct softnet_data {
struct Qdisc *output_queue;
struct Qdisc **output_queue_tailp;
struct list_head poll_list;
struct sk_buff *completion_queue;
struct sk_buff_head process_queue;
/* stats */
@ -2340,10 +2337,17 @@ struct softnet_data {
unsigned int time_squeeze;
unsigned int cpu_collision;
unsigned int received_rps;
#ifdef CONFIG_RPS
struct softnet_data *rps_ipi_list;
#endif
#ifdef CONFIG_NET_FLOW_LIMIT
struct sd_flow_limit __rcu *flow_limit;
#endif
struct Qdisc *output_queue;
struct Qdisc **output_queue_tailp;
struct sk_buff *completion_queue;
#ifdef CONFIG_RPS
/* Elements below can be accessed between CPUs for RPS */
struct call_single_data csd ____cacheline_aligned_in_smp;
struct softnet_data *rps_ipi_next;
@ -2355,9 +2359,6 @@ struct softnet_data {
struct sk_buff_head input_pkt_queue;
struct napi_struct backlog;
#ifdef CONFIG_NET_FLOW_LIMIT
struct sd_flow_limit __rcu *flow_limit;
#endif
};
static inline void input_queue_head_incr(struct softnet_data *sd)