[NET]: Add const markers to various variables.

the patch below marks various variables const in net/; the goal is to
move them to the .rodata section so that they can't false-share
cachelines with things that get written to, as well as potentially
helping gcc a bit with optimisations.  (these were found using a gcc
patch to warn about such variables)

Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ipv4/fib_hash.c

@@ -975,7 +975,7 @@ static void fib_seq_stop(struct seq_file *seq, void *v)
 
 static unsigned fib_flag_trans(int type, u32 mask, struct fib_info *fi)
 {
-	static unsigned type2flags[RTN_MAX + 1] = {
+	static const unsigned type2flags[RTN_MAX + 1] = {
 		[7] = RTF_REJECT, [8] = RTF_REJECT,
 	};
 	unsigned flags = type2flags[type];

net/ipv4/fib_semantics.c

@@ -83,7 +83,7 @@ for (nhsel=0; nhsel < 1; nhsel++)
 #define endfor_nexthops(fi) }
 
 
-static struct 
+static const struct 
 {
 	int	error;
 	u8	scope;

net/ipv4/icmp.c

@@ -220,7 +220,7 @@ struct icmp_control {
 	short   error;		/* This ICMP is classed as an error message */
 };
 
-static struct icmp_control icmp_pointers[NR_ICMP_TYPES+1];
+static const struct icmp_control icmp_pointers[NR_ICMP_TYPES+1];
 
 /*
  *	The ICMP socket(s). This is the most convenient way to flow control
@@ -994,7 +994,7 @@ error:
 /*
  *	This table is the definition of how we handle ICMP.
  */
-static struct icmp_control icmp_pointers[NR_ICMP_TYPES + 1] = {
+static const struct icmp_control icmp_pointers[NR_ICMP_TYPES + 1] = {
 	[ICMP_ECHOREPLY] = {
 		.output_entry = ICMP_MIB_OUTECHOREPS,
 		.input_entry = ICMP_MIB_INECHOREPS,

net/ipv4/ipvs/ip_vs_conn.c

@@ -771,7 +771,7 @@ static inline int todrop_entry(struct ip_vs_conn *cp)
 	 * The drop rate array needs tuning for real environments.
 	 * Called from timer bh only => no locking
 	 */
-	static char todrop_rate[9] = {0, 1, 2, 3, 4, 5, 6, 7, 8};
+	static const char todrop_rate[9] = {0, 1, 2, 3, 4, 5, 6, 7, 8};
 	static char todrop_counter[9] = {0};
 	int i;
 

net/ipv4/ipvs/ip_vs_ctl.c

@@ -1909,7 +1909,7 @@ static int ip_vs_set_timeout(struct ip_vs_timeout_user *u)
 #define DAEMON_ARG_LEN		(sizeof(struct ip_vs_daemon_user))
 #define MAX_ARG_LEN		SVCDEST_ARG_LEN
 
-static unsigned char set_arglen[SET_CMDID(IP_VS_SO_SET_MAX)+1] = {
+static const unsigned char set_arglen[SET_CMDID(IP_VS_SO_SET_MAX)+1] = {
 	[SET_CMDID(IP_VS_SO_SET_ADD)]		= SERVICE_ARG_LEN,
 	[SET_CMDID(IP_VS_SO_SET_EDIT)]		= SERVICE_ARG_LEN,
 	[SET_CMDID(IP_VS_SO_SET_DEL)]		= SERVICE_ARG_LEN,
@@ -2180,7 +2180,7 @@ __ip_vs_get_timeouts(struct ip_vs_timeout_user *u)
 #define GET_TIMEOUT_ARG_LEN	(sizeof(struct ip_vs_timeout_user))
 #define GET_DAEMON_ARG_LEN	(sizeof(struct ip_vs_daemon_user) * 2)
 
-static unsigned char get_arglen[GET_CMDID(IP_VS_SO_GET_MAX)+1] = {
+static const unsigned char get_arglen[GET_CMDID(IP_VS_SO_GET_MAX)+1] = {
 	[GET_CMDID(IP_VS_SO_GET_VERSION)]	= 64,
 	[GET_CMDID(IP_VS_SO_GET_INFO)]		= GET_INFO_ARG_LEN,
 	[GET_CMDID(IP_VS_SO_GET_SERVICES)]	= GET_SERVICES_ARG_LEN,

net/ipv4/ipvs/ip_vs_proto_tcp.c

@@ -251,7 +251,7 @@ tcp_csum_check(struct sk_buff *skb, struct ip_vs_protocol *pp)
 #define TCP_DIR_OUTPUT		4
 #define TCP_DIR_INPUT_ONLY	8
 
-static int tcp_state_off[IP_VS_DIR_LAST] = {
+static const int tcp_state_off[IP_VS_DIR_LAST] = {
 	[IP_VS_DIR_INPUT]		=	TCP_DIR_INPUT,
 	[IP_VS_DIR_OUTPUT]		=	TCP_DIR_OUTPUT,
 	[IP_VS_DIR_INPUT_ONLY]		=	TCP_DIR_INPUT_ONLY,

net/ipv4/netfilter/ip_conntrack_amanda.c

@@ -37,7 +37,7 @@ MODULE_LICENSE("GPL");
 module_param(master_timeout, int, 0600);
 MODULE_PARM_DESC(master_timeout, "timeout for the master connection");
 
-static char *conns[] = { "DATA ", "MESG ", "INDEX " };
+static const char *conns[] = { "DATA ", "MESG ", "INDEX " };
 
 /* This is slow, but it's simple. --RR */
 static char *amanda_buffer;

net/ipv4/netfilter/ip_conntrack_ftp.c

@@ -55,7 +55,7 @@ static int try_rfc959(const char *, size_t, u_int32_t [], char);
 static int try_eprt(const char *, size_t, u_int32_t [], char);
 static int try_epsv_response(const char *, size_t, u_int32_t [], char);
 
-static struct ftp_search {
+static const struct ftp_search {
 	enum ip_conntrack_dir dir;
 	const char *pattern;
 	size_t plen;

net/ipv4/netfilter/ip_conntrack_irc.c

@@ -59,7 +59,7 @@ MODULE_PARM_DESC(max_dcc_channels, "max number of expected DCC channels per IRC
 module_param(dcc_timeout, int, 0400);
 MODULE_PARM_DESC(dcc_timeout, "timeout on for unestablished DCC channels");
 
-static char *dccprotos[] = { "SEND ", "CHAT ", "MOVE ", "TSEND ", "SCHAT " };
+static const char *dccprotos[] = { "SEND ", "CHAT ", "MOVE ", "TSEND ", "SCHAT " };
 #define MINMATCHLEN	5
 
 #if 0

net/ipv4/netfilter/ip_conntrack_proto_icmp.c

@@ -51,7 +51,7 @@ static int icmp_invert_tuple(struct ip_conntrack_tuple *tuple,
 			     const struct ip_conntrack_tuple *orig)
 {
 	/* Add 1; spaces filled with 0. */
-	static u_int8_t invmap[]
+	static const u_int8_t invmap[]
 		= { [ICMP_ECHO] = ICMP_ECHOREPLY + 1,
 		    [ICMP_ECHOREPLY] = ICMP_ECHO + 1,
 		    [ICMP_TIMESTAMP] = ICMP_TIMESTAMPREPLY + 1,
@@ -110,7 +110,7 @@ static int icmp_packet(struct ip_conntrack *ct,
 	return NF_ACCEPT;
 }
 
-static u_int8_t valid_new[] = { 
+static const u_int8_t valid_new[] = { 
 	[ICMP_ECHO] = 1,
 	[ICMP_TIMESTAMP] = 1,
 	[ICMP_INFO_REQUEST] = 1,

net/ipv4/netfilter/ip_conntrack_proto_sctp.c

@@ -65,7 +65,7 @@ static unsigned long ip_ct_sctp_timeout_shutdown_sent     = 300 SECS / 1000;
 static unsigned long ip_ct_sctp_timeout_shutdown_recd     = 300 SECS / 1000;
 static unsigned long ip_ct_sctp_timeout_shutdown_ack_sent =   3 SECS;
 
-static unsigned long * sctp_timeouts[]
+static const unsigned long * sctp_timeouts[]
 = { NULL,                                  /* SCTP_CONNTRACK_NONE  */
     &ip_ct_sctp_timeout_closed,	           /* SCTP_CONNTRACK_CLOSED */
     &ip_ct_sctp_timeout_cookie_wait,       /* SCTP_CONNTRACK_COOKIE_WAIT */
@@ -118,7 +118,7 @@ cookie echoed to closed.
 */
 
 /* SCTP conntrack state transitions */
-static enum sctp_conntrack sctp_conntracks[2][9][SCTP_CONNTRACK_MAX] = {
+static const enum sctp_conntrack sctp_conntracks[2][9][SCTP_CONNTRACK_MAX] = {
 	{
 /*	ORIGINAL	*/
 /*                  sNO, sCL, sCW, sCE, sES, sSS, sSR, sSA */

net/ipv4/netfilter/ip_conntrack_proto_tcp.c

@@ -99,7 +99,7 @@ unsigned long ip_ct_tcp_timeout_close =        10 SECS;
    to ~13-30min depending on RTO. */
 unsigned long ip_ct_tcp_timeout_max_retrans =     5 MINS;
  
-static unsigned long * tcp_timeouts[]
+static const unsigned long * tcp_timeouts[]
 = { NULL,                              /*      TCP_CONNTRACK_NONE */
     &ip_ct_tcp_timeout_syn_sent,       /*      TCP_CONNTRACK_SYN_SENT, */
     &ip_ct_tcp_timeout_syn_recv,       /*      TCP_CONNTRACK_SYN_RECV, */
@@ -170,7 +170,7 @@ enum tcp_bit_set {
  *	if they are invalid
  *	or we do not support the request (simultaneous open)
  */
-static enum tcp_conntrack tcp_conntracks[2][6][TCP_CONNTRACK_MAX] = {
+static const enum tcp_conntrack tcp_conntracks[2][6][TCP_CONNTRACK_MAX] = {
 	{
 /* ORIGINAL */
 /* 	     sNO, sSS, sSR, sES, sFW, sCW, sLA, sTW, sCL, sLI	*/
@@ -817,7 +817,7 @@ void ip_conntrack_tcp_update(struct sk_buff *skb,
 #define	TH_CWR	0x80
 
 /* table of valid flag combinations - ECE and CWR are always valid */
-static u8 tcp_valid_flags[(TH_FIN|TH_SYN|TH_RST|TH_PUSH|TH_ACK|TH_URG) + 1] =
+static const u8 tcp_valid_flags[(TH_FIN|TH_SYN|TH_RST|TH_PUSH|TH_ACK|TH_URG) + 1] =
 {
 	[TH_SYN]			= 1,
 	[TH_SYN|TH_ACK]			= 1,

net/ipv4/netfilter/ip_tables.c

@@ -1892,7 +1892,7 @@ static int ipt_get_matches(char *buffer, char **start, off_t offset, int length)
 	return pos;
 }
 
-static struct { char *name; get_info_t *get_info; } ipt_proc_entry[] =
+static const struct { char *name; get_info_t *get_info; } ipt_proc_entry[] =
 { { "ip_tables_names", ipt_get_tables },
   { "ip_tables_targets", ipt_get_targets },
   { "ip_tables_matches", ipt_get_matches },

net/ipv4/netfilter/ipt_LOG.c

@@ -197,7 +197,7 @@ static void dump_packet(const struct nf_loginfo *info,
 	}
 	case IPPROTO_ICMP: {
 		struct icmphdr _icmph, *ich;
-		static size_t required_len[NR_ICMP_TYPES+1]
+		static const size_t required_len[NR_ICMP_TYPES+1]
 			= { [ICMP_ECHOREPLY] = 4,
 			    [ICMP_DEST_UNREACH]
 			    = 8 + sizeof(struct iphdr),

net/ipv4/proc.c

@@ -98,7 +98,7 @@ fold_field(void *mib[], int offt)
 }
 
 /* snmp items */
-static struct snmp_mib snmp4_ipstats_list[] = {
+static const struct snmp_mib snmp4_ipstats_list[] = {
 	SNMP_MIB_ITEM("InReceives", IPSTATS_MIB_INRECEIVES),
 	SNMP_MIB_ITEM("InHdrErrors", IPSTATS_MIB_INHDRERRORS),
 	SNMP_MIB_ITEM("InAddrErrors", IPSTATS_MIB_INADDRERRORS),
@@ -119,7 +119,7 @@ static struct snmp_mib snmp4_ipstats_list[] = {
 	SNMP_MIB_SENTINEL
 };
 
-static struct snmp_mib snmp4_icmp_list[] = {
+static const struct snmp_mib snmp4_icmp_list[] = {
 	SNMP_MIB_ITEM("InMsgs", ICMP_MIB_INMSGS),
 	SNMP_MIB_ITEM("InErrors", ICMP_MIB_INERRORS),
 	SNMP_MIB_ITEM("InDestUnreachs", ICMP_MIB_INDESTUNREACHS),
@@ -149,7 +149,7 @@ static struct snmp_mib snmp4_icmp_list[] = {
 	SNMP_MIB_SENTINEL
 };
 
-static struct snmp_mib snmp4_tcp_list[] = {
+static const struct snmp_mib snmp4_tcp_list[] = {
 	SNMP_MIB_ITEM("RtoAlgorithm", TCP_MIB_RTOALGORITHM),
 	SNMP_MIB_ITEM("RtoMin", TCP_MIB_RTOMIN),
 	SNMP_MIB_ITEM("RtoMax", TCP_MIB_RTOMAX),
@@ -167,7 +167,7 @@ static struct snmp_mib snmp4_tcp_list[] = {
 	SNMP_MIB_SENTINEL
 };
 
-static struct snmp_mib snmp4_udp_list[] = {
+static const struct snmp_mib snmp4_udp_list[] = {
 	SNMP_MIB_ITEM("InDatagrams", UDP_MIB_INDATAGRAMS),
 	SNMP_MIB_ITEM("NoPorts", UDP_MIB_NOPORTS),
 	SNMP_MIB_ITEM("InErrors", UDP_MIB_INERRORS),
@@ -175,7 +175,7 @@ static struct snmp_mib snmp4_udp_list[] = {
 	SNMP_MIB_SENTINEL
 };
 
-static struct snmp_mib snmp4_net_list[] = {
+static const struct snmp_mib snmp4_net_list[] = {
 	SNMP_MIB_ITEM("SyncookiesSent", LINUX_MIB_SYNCOOKIESSENT),
 	SNMP_MIB_ITEM("SyncookiesRecv", LINUX_MIB_SYNCOOKIESRECV),
 	SNMP_MIB_ITEM("SyncookiesFailed", LINUX_MIB_SYNCOOKIESFAILED),

net/ipv4/route.c

@@ -1371,7 +1371,7 @@ out:	kfree_skb(skb);
  *	are needed for AMPRnet AX.25 paths.
  */
 
-static unsigned short mtu_plateau[] =
+static const unsigned short mtu_plateau[] =
 {32000, 17914, 8166, 4352, 2002, 1492, 576, 296, 216, 128 };
 
 static __inline__ unsigned short guess_mtu(unsigned short old_mtu)

net/ipv4/tcp.c

@@ -1413,7 +1413,7 @@ recv_urg:
  *	closed.
  */
 
-static unsigned char new_state[16] = {
+static const unsigned char new_state[16] = {
   /* current state:        new state:      action:	*/
   /* (Invalid)		*/ TCP_CLOSE,
   /* TCP_ESTABLISHED	*/ TCP_FIN_WAIT1 | TCP_ACTION_FIN,

net/ipv6/icmp.c

@@ -751,7 +751,7 @@ void icmpv6_cleanup(void)
 	inet6_del_protocol(&icmpv6_protocol, IPPROTO_ICMPV6);
 }
 
-static struct icmp6_err {
+static const struct icmp6_err {
 	int err;
 	int fatal;
 } tab_unreach[] = {

net/ipv6/netfilter/ip6_tables.c

@@ -1972,7 +1972,7 @@ static int ip6t_get_matches(char *buffer, char **start, off_t offset, int length
 	return pos;
 }
 
-static struct { char *name; get_info_t *get_info; } ip6t_proc_entry[] =
+static const struct { char *name; get_info_t *get_info; } ip6t_proc_entry[] =
 { { "ip6_tables_names", ip6t_get_tables },
   { "ip6_tables_targets", ip6t_get_targets },
   { "ip6_tables_matches", ip6t_get_matches },