net: reorganize fields in netns_mib

Order fields to increase locality for most used protocols.

udplite and icmp are moved at the end.

Same for proc_net_devsnmp6 which is not used in fast path.

This potentially saves one cache line miss for typical TCP/UDP over IPv4/IPv6.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/netns/mib.h

@@ -5,22 +5,19 @@
 #include <net/snmp.h>
 
 struct netns_mib {
-	DEFINE_SNMP_STAT(struct tcp_mib, tcp_statistics);
 	DEFINE_SNMP_STAT(struct ipstats_mib, ip_statistics);
+#if IS_ENABLED(CONFIG_IPV6)
+	DEFINE_SNMP_STAT(struct ipstats_mib, ipv6_statistics);
+#endif
+
+	DEFINE_SNMP_STAT(struct tcp_mib, tcp_statistics);
 	DEFINE_SNMP_STAT(struct linux_mib, net_statistics);
-	DEFINE_SNMP_STAT(struct udp_mib, udp_statistics);
-	DEFINE_SNMP_STAT(struct udp_mib, udplite_statistics);
-	DEFINE_SNMP_STAT(struct icmp_mib, icmp_statistics);
-	DEFINE_SNMP_STAT_ATOMIC(struct icmpmsg_mib, icmpmsg_statistics);
 
+	DEFINE_SNMP_STAT(struct udp_mib, udp_statistics);
 #if IS_ENABLED(CONFIG_IPV6)
-	struct proc_dir_entry *proc_net_devsnmp6;
 	DEFINE_SNMP_STAT(struct udp_mib, udp_stats_in6);
-	DEFINE_SNMP_STAT(struct udp_mib, udplite_stats_in6);
-	DEFINE_SNMP_STAT(struct ipstats_mib, ipv6_statistics);
-	DEFINE_SNMP_STAT(struct icmpv6_mib, icmpv6_statistics);
-	DEFINE_SNMP_STAT_ATOMIC(struct icmpv6msg_mib, icmpv6msg_statistics);
 #endif
+
 #ifdef CONFIG_XFRM_STATISTICS
 	DEFINE_SNMP_STAT(struct linux_xfrm_mib, xfrm_statistics);
 #endif
@@ -30,6 +27,19 @@ struct netns_mib {
 #ifdef CONFIG_MPTCP
 	DEFINE_SNMP_STAT(struct mptcp_mib, mptcp_statistics);
 #endif
+
+	DEFINE_SNMP_STAT(struct udp_mib, udplite_statistics);
+#if IS_ENABLED(CONFIG_IPV6)
+	DEFINE_SNMP_STAT(struct udp_mib, udplite_stats_in6);
+#endif
+
+	DEFINE_SNMP_STAT(struct icmp_mib, icmp_statistics);
+	DEFINE_SNMP_STAT_ATOMIC(struct icmpmsg_mib, icmpmsg_statistics);
+#if IS_ENABLED(CONFIG_IPV6)
+	DEFINE_SNMP_STAT(struct icmpv6_mib, icmpv6_statistics);
+	DEFINE_SNMP_STAT_ATOMIC(struct icmpv6msg_mib, icmpv6msg_statistics);
+	struct proc_dir_entry *proc_net_devsnmp6;
+#endif
 };
 
 #endif