[PATCH net-next] net: make struct dst_entry::dev first member

[Alexey Dobriyan]

struct dst_entry::dev is used most often. Move it so it can be
accessed without imm8 offset on x86_64.

        add/remove: 0/0 grow/shrink: 9/239 up/down: 52/-413 (-361)
        function                                     old     new   delta
        dst_rcu_free                                 126     138     +12
        fnhe_flush_routes                            211     219      +8
        rt_set_nexthop                               747     754      +7
        rt_cache_route                                85      91      +6
        rt6_release                                  209     215      +6
        dst_release                                  107     111      +4
        dst_destroy_rcu                               29      33      +4
        dn_dst_check_expire                          329     333      +4
        dn_insert_route                              484     485      +1
        xfrm_resolve_and_create_bundle              2991    2990      -1
                                        ...
        ip_route_me_harder                          1163    1157      -6
        __ip_append_data.isra                       2730    2724      -6
        ip6_forward                                 3052    3045      -7
        callforward_do_filter                        659     651      -8
        dst_gc_task                                  571     549     -22

Signed-off-by: Alexey Dobriyan <adobri...@gmail.com>
---

 include/net/dst.h |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/include/net/dst.h
+++ b/include/net/dst.h
@@ -31,9 +31,9 @@
 struct sk_buff;
 
 struct dst_entry {
+       struct net_device       *dev;
        struct rcu_head         rcu_head;
        struct dst_entry        *child;
-       struct net_device       *dev;
        struct  dst_ops         *ops;
        unsigned long           _metrics;
        unsigned long           expires;