net: move inet_dport/inet_num in sock_common

commit 68835aba4d9b (net: optimize INET input path further)
moved some fields used for tcp/udp sockets lookup in the first cache
line of struct sock_common.

This patch moves inet_dport/inet_num as well, filling a 32bit hole
on 64 bit arches and reducing number of cache line misses in lookups.

Also change INET_MATCH()/INET_TW_MATCH() to perform the ports match
before addresses match, as this check is more discriminant.

Remove the hash check from MATCH() macros because we dont need to
re validate the hash value after taking a refcount on socket, and
use likely/unlikely compiler hints, as the sk_hash/hash check
makes the following conditional tests 100% predicted by cpu.

Introduce skc_addrpair/skc_portpair pair values to better
document the alignment requirements of the port/addr pairs
used in the various MATCH() macros, and remove some casts.

The namespace check can also be done at last.

This slightly improves TCP/UDP lookup times.

IP/TCP early demux needs inet->rx_dst_ifindex and
TCP needs inet->min_ttl, lets group them together in same cache line.

With help from Ben Hutchings & Joe Perches.

Idea of this patch came after Ling Ma proposal to move skc_hash
to the beginning of struct sock_common, and should allow him
to submit a final version of his patch. My tests show an improvement
doing so.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Ben Hutchings <bhutchings@solarflare.com>
Cc: Joe Perches <joe@perches.com>
Cc: Ling Ma <ling.ma.program@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 5 insertions, 3 deletions

diff --git a/include/net/inet_sock.h b/include/net/inet_sock.h
index 256c1ed2d69..a4196cbc84e 100644
--- a/include/net/inet_sock.h
+++ b/include/net/inet_sock.h
@@ -144,9 +144,11 @@ struct inet_sock {
         /* Socket demultiplex comparisons on incoming packets. */
 #define inet_daddr              sk.__sk_common.skc_daddr
 #define inet_rcv_saddr          sk.__sk_common.skc_rcv_saddr
+#define inet_addrpair           sk.__sk_common.skc_addrpair
+#define inet_dport              sk.__sk_common.skc_dport
+#define inet_num                sk.__sk_common.skc_num
+#define inet_portpair           sk.__sk_common.skc_portpair
 
-        __be16                  inet_dport;
-        __u16                   inet_num;
         __be32                  inet_saddr;
         __s16                   uc_ttl;
         __u16                   cmsg_flags;
@@ -154,6 +156,7 @@ struct inet_sock {
         __u16                   inet_id;
 
         struct ip_options_rcu __rcu     *inet_opt;
+        int                     rx_dst_ifindex;
         __u8                    tos;
         __u8                    min_ttl;
         __u8                    mc_ttl;
@@ -170,7 +173,6 @@ struct inet_sock {
         int                     uc_index;
         int                     mc_index;
         __be32                  mc_addr;
-        int                     rx_dst_ifindex;
         struct ip_mc_socklist __rcu     *mc_list;
         struct inet_cork_full   cork;
 };