neigh: reorder struct neighbour fields

Le mardi 12 octobre 2010 à 00:02 +0200, Eric Dumazet a écrit :
> Here is the followup patch.
>
> Thanks !
>

Oops, this was an old version, the up2date ones also took care of "used"
field.

I guess its time for a sleep, sorry again.

[PATCH net-next V2] neigh: reorder struct neighbour fields

(refcnt) and (ha_lock, ha, used, dev, output, ops, primary_key) should
be placed on a separate cache lines.

refcnt can be often written, while other fields are mostly read.

This gave me good result on stress test :

before:

real    0m45.570s
user    0m15.525s
sys     9m56.669s

After:

real    0m41.841s
user    0m15.261s
sys     8m45.949s

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet 2010-10-11 12:20:54 +00:00 committed by David S. Miller
parent fc66f95c68
commit e37ef961e5

View file

@ -94,8 +94,6 @@ struct neighbour {
struct neighbour __rcu *next;
struct neigh_table *tbl;
struct neigh_parms *parms;
struct net_device *dev;
unsigned long used;
unsigned long confirmed;
unsigned long updated;
__u8 flags;
@ -103,16 +101,18 @@ struct neighbour {
__u8 type;
__u8 dead;
atomic_t refcnt;
struct sk_buff_head arp_queue;
struct timer_list timer;
unsigned long used;
atomic_t probes;
rwlock_t lock;
seqlock_t ha_lock;
unsigned char ha[ALIGN(MAX_ADDR_LEN, sizeof(unsigned long))];
struct hh_cache *hh;
int (*output)(struct sk_buff *skb);
struct sk_buff_head arp_queue;
struct timer_list timer;
const struct neigh_ops *ops;
struct rcu_head rcu;
struct net_device *dev;
u8 primary_key[0];
};