[PATCH] [NET] inet_peer : group together avl_left, avl_right, v4daddr to speedup lookups on some CPUS

[Eric Dumazet]

Hi David

Lot of routers/embedded devices still use CPUS with 16/32 bytes cache lines. 
(486, Pentium, ...  PIII)
It makes sense to group together fields used at lookup time so they fit in one 
cache line.
This reduce cache footprint and speedup lookups.

Signed-off-by: Eric Dumazet <[EMAIL PROTECTED]>

--- net-2.6/include/net/inetpeer.h      2006-10-19 12:50:29.000000000 +0200
+++ net-2.6-ed/include/net/inetpeer.h   2006-10-19 12:52:08.000000000 +0200
@@ -17,14 +17,15 @@
 
 struct inet_peer
 {
+       /* group together avl_left,avl_right,v4daddr to speedup lookups */
        struct inet_peer        *avl_left, *avl_right;
+       __be32                  v4daddr;        /* peer's address */
+       __u16                   avl_height;
+       __u16                   ip_id_count;    /* IP ID for the next packet */
        struct inet_peer        *unused_next, **unused_prevp;
        __u32                   dtime;          /* the time of last use of not
                                                 * referenced entries */
        atomic_t                refcnt;
-       __be32                  v4daddr;        /* peer's address */
-       __u16                   avl_height;
-       __u16                   ip_id_count;    /* IP ID for the next packet */
        atomic_t                rid;            /* Frag reception counter */
        __u32                   tcp_ts;
        unsigned long           tcp_ts_stamp;