[NET]: use __read_mostly on kmem_cache_t , DEFINE_SNMP_STAT pointers
This patch puts mostly read only data in the right section
(read_mostly), to help sharing of these data between CPUS without
memory ping pongs.
On one of my production machine, tcp_statistics was sitting in a
heavily modified cache line, so *every* SNMP update had to force a
reload.
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/icmp.c b/net/ipv6/icmp.c
index ff685f2..5176fc6 100644
--- a/net/ipv6/icmp.c
+++ b/net/ipv6/icmp.c
@@ -67,7 +67,7 @@
#include <asm/uaccess.h>
#include <asm/system.h>
-DEFINE_SNMP_STAT(struct icmpv6_mib, icmpv6_statistics);
+DEFINE_SNMP_STAT(struct icmpv6_mib, icmpv6_statistics) __read_mostly;
/*
* The ICMP socket(s). This is the most convenient way to flow control
diff --git a/net/ipv6/ip6_fib.c b/net/ipv6/ip6_fib.c
index 1b354aa..16af874c 100644
--- a/net/ipv6/ip6_fib.c
+++ b/net/ipv6/ip6_fib.c
@@ -49,7 +49,7 @@
struct rt6_statistics rt6_stats;
-static kmem_cache_t * fib6_node_kmem;
+static kmem_cache_t * fib6_node_kmem __read_mostly;
enum fib_walk_state_t
{
diff --git a/net/ipv6/ipv6_sockglue.c b/net/ipv6/ipv6_sockglue.c
index 7516b88..76466af 100644
--- a/net/ipv6/ipv6_sockglue.c
+++ b/net/ipv6/ipv6_sockglue.c
@@ -55,7 +55,7 @@
#include <asm/uaccess.h>
-DEFINE_SNMP_STAT(struct ipstats_mib, ipv6_statistics);
+DEFINE_SNMP_STAT(struct ipstats_mib, ipv6_statistics) __read_mostly;
static struct packet_type ipv6_packet_type = {
.type = __constant_htons(ETH_P_IPV6),
diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index 67d9a04..390d750 100644
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -59,7 +59,7 @@
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
-DEFINE_SNMP_STAT(struct udp_mib, udp_stats_in6);
+DEFINE_SNMP_STAT(struct udp_mib, udp_stats_in6) __read_mostly;
/* Grrr, addr_type already calculated by caller, but I don't want
* to add some silly "cookie" argument to this method just for that.
diff --git a/net/ipv6/xfrm6_tunnel.c b/net/ipv6/xfrm6_tunnel.c
index 60c26c8..fbef782 100644
--- a/net/ipv6/xfrm6_tunnel.c
+++ b/net/ipv6/xfrm6_tunnel.c
@@ -79,7 +79,7 @@
#define XFRM6_TUNNEL_SPI_MIN 1
#define XFRM6_TUNNEL_SPI_MAX 0xffffffff
-static kmem_cache_t *xfrm6_tunnel_spi_kmem;
+static kmem_cache_t *xfrm6_tunnel_spi_kmem __read_mostly;
#define XFRM6_TUNNEL_SPI_BYADDR_HSIZE 256
#define XFRM6_TUNNEL_SPI_BYSPI_HSIZE 256
