[NET]: Generic network statistics

This patch moves the following files in /proc:
	/proc/net/rt_cache_stat 	/proc/net/stat/rt_cache
	/proc/net/ip_conntrack_stat	/proc/net/stat/ip_conntrack
	/proc/net/arp_cache_stat	/proc/net/stat/arp_cache
	/proc/net/clip_arp_cache_stat	/proc/net/stat/clip_arp_cache
	/proc/net/dn_neigh_cache_stat	/proc/net/stat/dn_neigh_cache

This allows a generic statistics tool to scan for all available statistics
by doing readdir(2) on /proc/net/stat

It also adds a special first 'template' line to rt_cache and ip_conntrack
in order to facilitate compatibility once somebody adds new fields to the
output lines.

WARNING: 
	This breaks existing rtstat.c and ctstat.c userspace programs
	(hopefully for the last time).  rtstat is non-existant or broken in
	major distributions anyway, and ctstat is too new for any distros
	having it picked up.  Therefore, we justify this breakage.

A new unified statistics tool for routing cache, connection tracking and
neighbour cache is under development and will be included with iproute2.
Signed-off-by: Harald Welte <laforge@gnumonks.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

fs/proc/root.c

@@ -18,7 +18,7 @@
 #include <asm/bitops.h>
 #include <linux/smp_lock.h>
 
-struct proc_dir_entry *proc_net, *proc_bus, *proc_root_fs, *proc_root_driver;
+struct proc_dir_entry *proc_net, *proc_net_stat, *proc_bus, *proc_root_fs, *proc_root_driver;
 
 #ifdef CONFIG_SYSCTL
 struct proc_dir_entry *proc_sys_root;
@@ -53,6 +53,8 @@ void __init proc_root_init(void)
 	}
 	proc_misc_init();
 	proc_net = proc_mkdir("net", NULL);
+	proc_net_stat = proc_mkdir("net/stat", NULL);
+
 #ifdef CONFIG_SYSVIPC
 	proc_mkdir("sysvipc", NULL);
 #endif
@@ -157,5 +159,6 @@ EXPORT_SYMBOL(remove_proc_entry);
 EXPORT_SYMBOL(proc_root);
 EXPORT_SYMBOL(proc_root_fs);
 EXPORT_SYMBOL(proc_net);
+EXPORT_SYMBOL(proc_net_stat);
 EXPORT_SYMBOL(proc_bus);
 EXPORT_SYMBOL(proc_root_driver);

include/linux/proc_fs.h

@@ -79,6 +79,7 @@ struct kcore_list {
 extern struct proc_dir_entry proc_root;
 extern struct proc_dir_entry *proc_root_fs;
 extern struct proc_dir_entry *proc_net;
+extern struct proc_dir_entry *proc_net_stat;
 extern struct proc_dir_entry *proc_bus;
 extern struct proc_dir_entry *proc_root_driver;
 extern struct proc_dir_entry *proc_root_kcore;

net/core/neighbour.c

@@ -1334,22 +1334,11 @@ void neigh_table_init(struct neigh_table *tbl)
 		panic("cannot create neighbour cache statistics");
 	
 #ifdef CONFIG_PROC_FS
-#define NC_STAT_SUFFIX "_stat"
-	{
-	char *proc_stat_name;
-	proc_stat_name = kmalloc(strlen(tbl->id) + 
-				 strlen(NC_STAT_SUFFIX) + 1, GFP_KERNEL);
-	if (!proc_stat_name)
-		panic("cannot allocate neighbour cache proc name buffer");
-	strcpy(proc_stat_name, tbl->id);
-	strcat(proc_stat_name, NC_STAT_SUFFIX);
-
-	tbl->pde = create_proc_entry(proc_stat_name, 0, proc_net);
+	tbl->pde = create_proc_entry(tbl->id, 0, proc_net_stat);
 	if (!tbl->pde) 
 		panic("cannot create neighbour proc dir entry");
 	tbl->pde->proc_fops = &neigh_stat_seq_fops;
 	tbl->pde->data = tbl;
-	}
 #endif
 
 	tbl->hash_mask = 1;

net/ipv4/netfilter/ip_conntrack_standalone.c

@@ -268,10 +268,13 @@ static void *ct_cpu_seq_start(struct seq_file *seq, loff_t *pos)
 {
 	int cpu;
 
-	for (cpu = *pos; cpu < NR_CPUS; ++cpu) {
+	if (*pos == 0)
+		return SEQ_START_TOKEN;
+
+	for (cpu = *pos-1; cpu < NR_CPUS; ++cpu) {
 		if (!cpu_possible(cpu))
 			continue;
-		*pos = cpu;
+		*pos = cpu+1;
 		return &per_cpu(ip_conntrack_stat, cpu);
 	}
 
@@ -282,10 +285,10 @@ static void *ct_cpu_seq_next(struct seq_file *seq, void *v, loff_t *pos)
 {
 	int cpu;
 
-	for (cpu = *pos + 1; cpu < NR_CPUS; ++cpu) {
+	for (cpu = *pos; cpu < NR_CPUS; ++cpu) {
 		if (!cpu_possible(cpu))
 			continue;
-		*pos = cpu;
+		*pos = cpu+1;
 		return &per_cpu(ip_conntrack_stat, cpu);
 	}
 
@@ -301,6 +304,11 @@ static int ct_cpu_seq_show(struct seq_file *seq, void *v)
 	unsigned int nr_conntracks = atomic_read(&ip_conntrack_count);
 	struct ip_conntrack_stat *st = v;
 
+	if (v == SEQ_START_TOKEN) {
+		seq_printf(seq, "entries  searched found new invalid ignore delete delete_list insert insert_failed drop early_drop icmp_error  expect_new expect_create expect_delete\n");
+		return 0;
+	}
+
 	seq_printf(seq, "%08x  %08x %08x %08x %08x %08x %08x %08x "
 			"%08x %08x %08x %08x %08x  %08x %08x %08x \n",
 		   nr_conntracks,
@@ -735,10 +743,11 @@ static int init_or_cleanup(int init)
 					&exp_file_ops);
 	if (!proc_exp) goto cleanup_proc;
 
-	proc_stat = proc_net_fops_create("ip_conntrack_stat", S_IRUGO,
-					 &ct_cpu_seq_fops);
+	proc_stat = create_proc_entry("ip_conntrack", S_IRUGO, proc_net_stat);
 	if (!proc_stat)
 		goto cleanup_proc_exp;
+
+	proc_stat->proc_fops = &ct_cpu_seq_fops;
 	proc_stat->owner = THIS_MODULE;
 #endif
 

net/ipv4/route.c

@@ -356,10 +356,13 @@ static void *rt_cpu_seq_start(struct seq_file *seq, loff_t *pos)
 {
 	int cpu;
 
-	for (cpu = *pos; cpu < NR_CPUS; ++cpu) {
+	if (*pos == 0)
+		return SEQ_START_TOKEN;
+
+	for (cpu = *pos-1; cpu < NR_CPUS; ++cpu) {
 		if (!cpu_possible(cpu))
 			continue;
-		*pos = cpu;
+		*pos = cpu+1;
 		return per_cpu_ptr(rt_cache_stat, cpu);
 	}
 	return NULL;
@@ -369,10 +372,10 @@ static void *rt_cpu_seq_next(struct seq_file *seq, void *v, loff_t *pos)
 {
 	int cpu;
 
-	for (cpu = *pos + 1; cpu < NR_CPUS; ++cpu) {
+	for (cpu = *pos; cpu < NR_CPUS; ++cpu) {
 		if (!cpu_possible(cpu))
 			continue;
-		*pos = cpu;
+		*pos = cpu+1;
 		return per_cpu_ptr(rt_cache_stat, cpu);
 	}
 	return NULL;
@@ -388,6 +391,11 @@ static int rt_cpu_seq_show(struct seq_file *seq, void *v)
 {
 	struct rt_cache_stat *st = v;
 
+	if (v == SEQ_START_TOKEN) {
+		seq_printf(seq, "entries  in_hit in_slow_tot in_no_route in_brd in_martian_dst in_martian_src  out_hit out_slow_tot out_slow_mc  gc_total gc_ignored gc_goal_miss gc_dst_overflow in_hlist_search out_hlist_search\n");
+		return 0;
+	}
+	
 	seq_printf(seq,"%08x  %08x %08x %08x %08x %08x %08x %08x "
 		   " %08x %08x %08x %08x %08x %08x %08x %08x %08x \n",
 		   atomic_read(&ipv4_dst_ops.entries),
@@ -2783,12 +2791,16 @@ int __init ip_rt_init(void)
 	add_timer(&rt_secret_timer);
 
 #ifdef CONFIG_PROC_FS
+	{
+	struct proc_dir_entry *rtstat_pde = NULL; /* keep gcc happy */
 	if (!proc_net_fops_create("rt_cache", S_IRUGO, &rt_cache_seq_fops) ||
-	    !proc_net_fops_create("rt_cache_stat", S_IRUGO, &rt_cpu_seq_fops)) {
+	    !(rtstat_pde = create_proc_entry("rt_cache", S_IRUGO, 
+			    		     proc_net_stat))) {
 		free_percpu(rt_cache_stat);
 		return -ENOMEM;
 	}
-
+	rtstat_pde->proc_fops = &rt_cpu_seq_fops;
+	}
 #ifdef CONFIG_NET_CLS_ROUTE
 	create_proc_read_entry("rt_acct", 0, proc_net, ip_rt_acct_read, NULL);
 #endif