[NET/IPV4/IPV6]: Change some sysctl variables to __read_mostly
Change net/core, ipv4 and ipv6 sysctl variables to __read_mostly.
Couldn't actually measure any performance increase while testing (.3%
I consider noise), but seems like the right thing to do.
Signed-off-by: Brian Haley <brian.haley@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/core/neighbour.c b/net/core/neighbour.c
index 23ae5e5..c7e653f 100644
--- a/net/core/neighbour.c
+++ b/net/core/neighbour.c
@@ -2451,7 +2451,7 @@
ctl_table neigh_neigh_dir[2];
ctl_table neigh_proto_dir[2];
ctl_table neigh_root_dir[2];
-} neigh_sysctl_template = {
+} neigh_sysctl_template __read_mostly = {
.neigh_vars = {
{
.ctl_name = NET_NEIGH_MCAST_SOLICIT,
diff --git a/net/core/sock.c b/net/core/sock.c
index b67d868..cfaf090 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -187,13 +187,13 @@
#define SK_RMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
/* Run time adjustable parameters. */
-__u32 sysctl_wmem_max = SK_WMEM_MAX;
-__u32 sysctl_rmem_max = SK_RMEM_MAX;
-__u32 sysctl_wmem_default = SK_WMEM_MAX;
-__u32 sysctl_rmem_default = SK_RMEM_MAX;
+__u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX;
+__u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX;
+__u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX;
+__u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX;
/* Maximal space eaten by iovec or ancilliary data plus some space */
-int sysctl_optmem_max = sizeof(unsigned long)*(2*UIO_MAXIOV + 512);
+int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512);
static int sock_set_timeout(long *timeo_p, char __user *optval, int optlen)
{
diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c
index 36c38bf..f2e8927 100644
--- a/net/ipv4/af_inet.c
+++ b/net/ipv4/af_inet.c
@@ -391,7 +391,7 @@
}
/* It is off by default, see below. */
-int sysctl_ip_nonlocal_bind;
+int sysctl_ip_nonlocal_bind __read_mostly;
int inet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
{
@@ -987,7 +987,7 @@
* Shall we try to damage output packets if routing dev changes?
*/
-int sysctl_ip_dynaddr;
+int sysctl_ip_dynaddr __read_mostly;
static int inet_sk_reselect_saddr(struct sock *sk)
{
diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c
index 6d223e5..c2ad07e 100644
--- a/net/ipv4/icmp.c
+++ b/net/ipv4/icmp.c
@@ -187,11 +187,11 @@
};
/* Control parameters for ECHO replies. */
-int sysctl_icmp_echo_ignore_all;
-int sysctl_icmp_echo_ignore_broadcasts = 1;
+int sysctl_icmp_echo_ignore_all __read_mostly;
+int sysctl_icmp_echo_ignore_broadcasts __read_mostly = 1;
/* Control parameter - ignore bogus broadcast responses? */
-int sysctl_icmp_ignore_bogus_error_responses = 1;
+int sysctl_icmp_ignore_bogus_error_responses __read_mostly = 1;
/*
* Configurable global rate limit.
@@ -205,9 +205,9 @@
* time exceeded (11), parameter problem (12)
*/
-int sysctl_icmp_ratelimit = 1 * HZ;
-int sysctl_icmp_ratemask = 0x1818;
-int sysctl_icmp_errors_use_inbound_ifaddr;
+int sysctl_icmp_ratelimit __read_mostly = 1 * HZ;
+int sysctl_icmp_ratemask __read_mostly = 0x1818;
+int sysctl_icmp_errors_use_inbound_ifaddr __read_mostly;
/*
* ICMP control array. This specifies what to do with each ICMP.
diff --git a/net/ipv4/igmp.c b/net/ipv4/igmp.c
index 7003e76..58be822 100644
--- a/net/ipv4/igmp.c
+++ b/net/ipv4/igmp.c
@@ -1397,8 +1397,8 @@
/*
* Join a socket to a group
*/
-int sysctl_igmp_max_memberships = IP_MAX_MEMBERSHIPS;
-int sysctl_igmp_max_msf = IP_MAX_MSF;
+int sysctl_igmp_max_memberships __read_mostly = IP_MAX_MEMBERSHIPS;
+int sysctl_igmp_max_msf __read_mostly = IP_MAX_MSF;
static int ip_mc_del1_src(struct ip_mc_list *pmc, int sfmode,
diff --git a/net/ipv4/ip_fragment.c b/net/ipv4/ip_fragment.c
index 8d7f107..165d728 100644
--- a/net/ipv4/ip_fragment.c
+++ b/net/ipv4/ip_fragment.c
@@ -54,15 +54,15 @@
* even the most extreme cases without allowing an attacker to measurably
* harm machine performance.
*/
-int sysctl_ipfrag_high_thresh = 256*1024;
-int sysctl_ipfrag_low_thresh = 192*1024;
+int sysctl_ipfrag_high_thresh __read_mostly = 256*1024;
+int sysctl_ipfrag_low_thresh __read_mostly = 192*1024;
-int sysctl_ipfrag_max_dist = 64;
+int sysctl_ipfrag_max_dist __read_mostly = 64;
/* Important NOTE! Fragment queue must be destroyed before MSL expires.
* RFC791 is wrong proposing to prolongate timer each fragment arrival by TTL.
*/
-int sysctl_ipfrag_time = IP_FRAG_TIME;
+int sysctl_ipfrag_time __read_mostly = IP_FRAG_TIME;
struct ipfrag_skb_cb
{
@@ -130,7 +130,7 @@
}
static struct timer_list ipfrag_secret_timer;
-int sysctl_ipfrag_secret_interval = 10 * 60 * HZ;
+int sysctl_ipfrag_secret_interval __read_mostly = 10 * 60 * HZ;
static void ipfrag_secret_rebuild(unsigned long dummy)
{
diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c
index 1b9b674..81b2795 100644
--- a/net/ipv4/ip_output.c
+++ b/net/ipv4/ip_output.c
@@ -83,7 +83,7 @@
#include <linux/netlink.h>
#include <linux/tcp.h>
-int sysctl_ip_default_ttl = IPDEFTTL;
+int sysctl_ip_default_ttl __read_mostly = IPDEFTTL;
/* Generate a checksum for an outgoing IP datagram. */
__inline__ void ip_send_check(struct iphdr *iph)
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index b0124e69..e570db4 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -268,7 +268,7 @@
#include <asm/uaccess.h>
#include <asm/ioctls.h>
-int sysctl_tcp_fin_timeout = TCP_FIN_TIMEOUT;
+int sysctl_tcp_fin_timeout __read_mostly = TCP_FIN_TIMEOUT;
DEFINE_SNMP_STAT(struct tcp_mib, tcp_statistics) __read_mostly;
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 159fa3f..caf3c41 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -72,24 +72,24 @@
#include <asm/unaligned.h>
#include <net/netdma.h>
-int sysctl_tcp_timestamps = 1;
-int sysctl_tcp_window_scaling = 1;
-int sysctl_tcp_sack = 1;
-int sysctl_tcp_fack = 1;
-int sysctl_tcp_reordering = TCP_FASTRETRANS_THRESH;
-int sysctl_tcp_ecn;
-int sysctl_tcp_dsack = 1;
-int sysctl_tcp_app_win = 31;
-int sysctl_tcp_adv_win_scale = 2;
+int sysctl_tcp_timestamps __read_mostly = 1;
+int sysctl_tcp_window_scaling __read_mostly = 1;
+int sysctl_tcp_sack __read_mostly = 1;
+int sysctl_tcp_fack __read_mostly = 1;
+int sysctl_tcp_reordering __read_mostly = TCP_FASTRETRANS_THRESH;
+int sysctl_tcp_ecn __read_mostly;
+int sysctl_tcp_dsack __read_mostly = 1;
+int sysctl_tcp_app_win __read_mostly = 31;
+int sysctl_tcp_adv_win_scale __read_mostly = 2;
-int sysctl_tcp_stdurg;
-int sysctl_tcp_rfc1337;
-int sysctl_tcp_max_orphans = NR_FILE;
-int sysctl_tcp_frto;
-int sysctl_tcp_nometrics_save;
+int sysctl_tcp_stdurg __read_mostly;
+int sysctl_tcp_rfc1337 __read_mostly;
+int sysctl_tcp_max_orphans __read_mostly = NR_FILE;
+int sysctl_tcp_frto __read_mostly;
+int sysctl_tcp_nometrics_save __read_mostly;
-int sysctl_tcp_moderate_rcvbuf = 1;
-int sysctl_tcp_abc;
+int sysctl_tcp_moderate_rcvbuf __read_mostly = 1;
+int sysctl_tcp_abc __read_mostly;
#define FLAG_DATA 0x01 /* Incoming frame contained data. */
#define FLAG_WIN_UPDATE 0x02 /* Incoming ACK was a window update. */
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index 2973dee..23b46e3 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -78,8 +78,8 @@
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
-int sysctl_tcp_tw_reuse;
-int sysctl_tcp_low_latency;
+int sysctl_tcp_tw_reuse __read_mostly;
+int sysctl_tcp_low_latency __read_mostly;
/* Check TCP sequence numbers in ICMP packets. */
#define ICMP_MIN_LENGTH 8
diff --git a/net/ipv4/tcp_minisocks.c b/net/ipv4/tcp_minisocks.c
index 624e2b2..0163d98 100644
--- a/net/ipv4/tcp_minisocks.c
+++ b/net/ipv4/tcp_minisocks.c
@@ -34,8 +34,8 @@
#define SYNC_INIT 1
#endif
-int sysctl_tcp_syncookies = SYNC_INIT;
-int sysctl_tcp_abort_on_overflow;
+int sysctl_tcp_syncookies __read_mostly = SYNC_INIT;
+int sysctl_tcp_abort_on_overflow __read_mostly;
struct inet_timewait_death_row tcp_death_row = {
.sysctl_max_tw_buckets = NR_FILE * 2,
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index 9252a50..061edfa 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -43,24 +43,24 @@
#include <linux/smp_lock.h>
/* People can turn this off for buggy TCP's found in printers etc. */
-int sysctl_tcp_retrans_collapse = 1;
+int sysctl_tcp_retrans_collapse __read_mostly = 1;
/* People can turn this on to work with those rare, broken TCPs that
* interpret the window field as a signed quantity.
*/
-int sysctl_tcp_workaround_signed_windows = 0;
+int sysctl_tcp_workaround_signed_windows __read_mostly = 0;
/* This limits the percentage of the congestion window which we
* will allow a single TSO frame to consume. Building TSO frames
* which are too large can cause TCP streams to be bursty.
*/
-int sysctl_tcp_tso_win_divisor = 3;
+int sysctl_tcp_tso_win_divisor __read_mostly = 3;
-int sysctl_tcp_mtu_probing = 0;
-int sysctl_tcp_base_mss = 512;
+int sysctl_tcp_mtu_probing __read_mostly = 0;
+int sysctl_tcp_base_mss __read_mostly = 512;
/* By default, RFC2861 behavior. */
-int sysctl_tcp_slow_start_after_idle = 1;
+int sysctl_tcp_slow_start_after_idle __read_mostly = 1;
static void update_send_head(struct sock *sk, struct tcp_sock *tp,
struct sk_buff *skb)
diff --git a/net/ipv4/tcp_timer.c b/net/ipv4/tcp_timer.c
index 7c1bde3..fb09ade 100644
--- a/net/ipv4/tcp_timer.c
+++ b/net/ipv4/tcp_timer.c
@@ -23,14 +23,14 @@
#include <linux/module.h>
#include <net/tcp.h>
-int sysctl_tcp_syn_retries = TCP_SYN_RETRIES;
-int sysctl_tcp_synack_retries = TCP_SYNACK_RETRIES;
-int sysctl_tcp_keepalive_time = TCP_KEEPALIVE_TIME;
-int sysctl_tcp_keepalive_probes = TCP_KEEPALIVE_PROBES;
-int sysctl_tcp_keepalive_intvl = TCP_KEEPALIVE_INTVL;
-int sysctl_tcp_retries1 = TCP_RETR1;
-int sysctl_tcp_retries2 = TCP_RETR2;
-int sysctl_tcp_orphan_retries;
+int sysctl_tcp_syn_retries __read_mostly = TCP_SYN_RETRIES;
+int sysctl_tcp_synack_retries __read_mostly = TCP_SYNACK_RETRIES;
+int sysctl_tcp_keepalive_time __read_mostly = TCP_KEEPALIVE_TIME;
+int sysctl_tcp_keepalive_probes __read_mostly = TCP_KEEPALIVE_PROBES;
+int sysctl_tcp_keepalive_intvl __read_mostly = TCP_KEEPALIVE_INTVL;
+int sysctl_tcp_retries1 __read_mostly = TCP_RETR1;
+int sysctl_tcp_retries2 __read_mostly = TCP_RETR2;
+int sysctl_tcp_orphan_retries __read_mostly;
static void tcp_write_timer(unsigned long);
static void tcp_delack_timer(unsigned long);
diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index 4af741e..f1ede90 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -146,7 +146,7 @@
static ATOMIC_NOTIFIER_HEAD(inet6addr_chain);
-struct ipv6_devconf ipv6_devconf = {
+struct ipv6_devconf ipv6_devconf __read_mostly = {
.forwarding = 0,
.hop_limit = IPV6_DEFAULT_HOPLIMIT,
.mtu6 = IPV6_MIN_MTU,
@@ -177,7 +177,7 @@
#endif
};
-static struct ipv6_devconf ipv6_devconf_dflt = {
+static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
.forwarding = 0,
.hop_limit = IPV6_DEFAULT_HOPLIMIT,
.mtu6 = IPV6_MIN_MTU,
@@ -3665,7 +3665,7 @@
ctl_table addrconf_conf_dir[2];
ctl_table addrconf_proto_dir[2];
ctl_table addrconf_root_dir[2];
-} addrconf_sysctl = {
+} addrconf_sysctl __read_mostly = {
.sysctl_header = NULL,
.addrconf_vars = {
{
diff --git a/net/ipv6/af_inet6.c b/net/ipv6/af_inet6.c
index 82a1b1a..2ff600c 100644
--- a/net/ipv6/af_inet6.c
+++ b/net/ipv6/af_inet6.c
@@ -67,7 +67,7 @@
MODULE_DESCRIPTION("IPv6 protocol stack for Linux");
MODULE_LICENSE("GPL");
-int sysctl_ipv6_bindv6only;
+int sysctl_ipv6_bindv6only __read_mostly;
/* The inetsw table contains everything that inet_create needs to
* build a new socket.
diff --git a/net/ipv6/icmp.c b/net/ipv6/icmp.c
index 1030551..e3a8e27 100644
--- a/net/ipv6/icmp.c
+++ b/net/ipv6/icmp.c
@@ -151,7 +151,7 @@
return 0;
}
-static int sysctl_icmpv6_time = 1*HZ;
+static int sysctl_icmpv6_time __read_mostly = 1*HZ;
/*
* Check the ICMP output rate limit
diff --git a/net/ipv6/mcast.c b/net/ipv6/mcast.c
index 639eb20..3b114e3 100644
--- a/net/ipv6/mcast.c
+++ b/net/ipv6/mcast.c
@@ -171,7 +171,7 @@
#define IPV6_MLD_MAX_MSF 64
-int sysctl_mld_max_msf = IPV6_MLD_MAX_MSF;
+int sysctl_mld_max_msf __read_mostly = IPV6_MLD_MAX_MSF;
/*
* socket join on multicast group
diff --git a/net/ipv6/reassembly.c b/net/ipv6/reassembly.c
index a8623d2..f39bbed 100644
--- a/net/ipv6/reassembly.c
+++ b/net/ipv6/reassembly.c
@@ -53,10 +53,10 @@
#include <net/ndisc.h>
#include <net/addrconf.h>
-int sysctl_ip6frag_high_thresh = 256*1024;
-int sysctl_ip6frag_low_thresh = 192*1024;
+int sysctl_ip6frag_high_thresh __read_mostly = 256*1024;
+int sysctl_ip6frag_low_thresh __read_mostly = 192*1024;
-int sysctl_ip6frag_time = IPV6_FRAG_TIMEOUT;
+int sysctl_ip6frag_time __read_mostly = IPV6_FRAG_TIMEOUT;
struct ip6frag_skb_cb
{
@@ -152,7 +152,7 @@
}
static struct timer_list ip6_frag_secret_timer;
-int sysctl_ip6frag_secret_interval = 10 * 60 * HZ;
+int sysctl_ip6frag_secret_interval __read_mostly = 10 * 60 * HZ;
static void ip6_frag_secret_rebuild(unsigned long dummy)
{