[IPV4] fib_trie: size and statistics

Show number of entries in trie, the size field was being set but never used,
but it only counted leaves, not all entries. Refactor the two cases in
fib_triestat_seq_show into a single routine.

Note: the stat structure was being malloc'd but the stack usage isn't so
high (288 bytes) that it is worth the additional complexity.
Signed-off-by: Stephen Hemminger <stephen.hemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ipv4/fib_trie.c

@@ -148,10 +148,10 @@ struct trie_stat {
 
 struct trie {
 	struct node *trie;
+	unsigned int size;
 #ifdef CONFIG_IP_FIB_TRIE_STATS
 	struct trie_use_stats stats;
 #endif
-	int size;
 };
 
 static void put_child(struct trie *t, struct tnode *tn, int i, struct node *n);
@@ -1045,7 +1045,6 @@ static struct list_head *fib_insert_node(struct trie *t, u32 key, int plen)
 		insert_leaf_info(&l->list, li);
 		goto done;
 	}
-	t->size++;
 	l = leaf_new();
 
 	if (!l)
@@ -1261,6 +1260,8 @@ static int fn_trie_insert(struct fib_table *tb, struct fib_config *cfg)
 	list_add_tail_rcu(&new_fa->fa_list,
 			  (fa ? &fa->fa_list : fa_head));
 
+	t->size++;
+
 	rt_cache_flush(-1);
 	rtmsg_fib(RTM_NEWROUTE, htonl(key), new_fa, plen, tb->tb_id,
 		  &cfg->fc_nlinfo, 0);
@@ -2131,50 +2132,34 @@ static void trie_show_usage(struct seq_file *seq,
 }
 #endif /*  CONFIG_IP_FIB_TRIE_STATS */
 
+static void fib_trie_show(struct seq_file *seq, const char *name, struct trie *trie)
+{
+	struct trie_stat stat;
+
+	seq_printf(seq, "%s: %d\n", name, trie->size);
+	trie_collect_stats(trie, &stat);
+	trie_show_stats(seq, &stat);
+#ifdef CONFIG_IP_FIB_TRIE_STATS
+	trie_show_usage(seq, &trie->stats);
+#endif
+}
 
 static int fib_triestat_seq_show(struct seq_file *seq, void *v)
 {
 	struct net *net = (struct net *)seq->private;
-	struct trie *trie_local, *trie_main;
-	struct trie_stat *stat;
 	struct fib_table *tb;
 
-	trie_local = NULL;
+	seq_printf(seq,
+		   "Basic info: size of leaf: %Zd bytes, size of tnode: %Zd bytes.\n",
+		   sizeof(struct leaf), sizeof(struct tnode));
+
 	tb = fib_get_table(net, RT_TABLE_LOCAL);
 	if (tb)
-		trie_local = (struct trie *) tb->tb_data;
+		fib_trie_show(seq, "Local", (struct trie *) tb->tb_data);
 
-	trie_main = NULL;
 	tb = fib_get_table(net, RT_TABLE_MAIN);
 	if (tb)
-		trie_main = (struct trie *) tb->tb_data;
-
-
-	stat = kmalloc(sizeof(*stat), GFP_KERNEL);
-	if (!stat)
-		return -ENOMEM;
-
-	seq_printf(seq, "Basic info: size of leaf: %Zd bytes, size of tnode: %Zd bytes.\n",
-		   sizeof(struct leaf), sizeof(struct tnode));
-
-	if (trie_local) {
-		seq_printf(seq, "Local:\n");
-		trie_collect_stats(trie_local, stat);
-		trie_show_stats(seq, stat);
-#ifdef CONFIG_IP_FIB_TRIE_STATS
-		trie_show_usage(seq, &trie_local->stats);
-#endif
-	}
-
-	if (trie_main) {
-		seq_printf(seq, "Main:\n");
-		trie_collect_stats(trie_main, stat);
-		trie_show_stats(seq, stat);
-#ifdef CONFIG_IP_FIB_TRIE_STATS
-		trie_show_usage(seq, &trie_main->stats);
-#endif
-	}
-	kfree(stat);
+		fib_trie_show(seq, "Main", (struct trie *) tb->tb_data);
 
 	return 0;
 }