[PATCH net-next] net: reorganize fields in netns_mib

[Eric Dumazet]

From: Eric Dumazet <eduma...@google.com>

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 <eduma...@google.com>
---
 include/net/netns/mib.h | 30 ++++++++++++++++++++----------
 1 file changed, 20 insertions(+), 10 deletions(-)

diff --git a/include/net/netns/mib.h b/include/net/netns/mib.h
index 
59b2c3a3db423a1ffc256ac1f5d671a8cd438453..7e373664b1e7baaa7cdb3df572f2b5a78aff0a39
 100644
--- a/include/net/netns/mib.h
+++ b/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);
-
 #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
-- 
2.31.0.208.g409f899ff0-goog