ipv4: fib table algorithm performance improvement

The FIB algorithim for IPV4 is set at compile time, but kernel goes through
the overhead of function call indirection at runtime. Save some
cycles by turning the indirect calls to direct calls to either
hash or trie code.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 14 insertions, 11 deletions

diff --git a/include/net/ip_fib.h b/include/net/ip_fib.h
index ef91fe924ba..68fd5ebd094 100644
--- a/include/net/ip_fib.h
+++ b/include/net/ip_fib.h
@@ -144,18 +144,21 @@ struct fib_table {
 	struct hlist_node tb_hlist;
 	u32		tb_id;
 	int		tb_default;
-	int		(*tb_lookup)(struct fib_table *tb, const struct flowi *flp, struct fib_result *res);
-	int		(*tb_insert)(struct fib_table *, struct fib_config *);
-	int		(*tb_delete)(struct fib_table *, struct fib_config *);
-	int		(*tb_dump)(struct fib_table *table, struct sk_buff *skb,
-				     struct netlink_callback *cb);
-	int		(*tb_flush)(struct fib_table *table);
-	void		(*tb_select_default)(struct fib_table *table,
-					     const struct flowi *flp, struct fib_result *res);
-
 	unsigned char	tb_data[0];
 };
 
+extern int fib_table_lookup(struct fib_table *tb, const struct flowi *flp,
+			    struct fib_result *res);
+extern int fib_table_insert(struct fib_table *, struct fib_config *);
+extern int fib_table_delete(struct fib_table *, struct fib_config *);
+extern int fib_table_dump(struct fib_table *table, struct sk_buff *skb,
+			  struct netlink_callback *cb);
+extern int fib_table_flush(struct fib_table *table);
+extern void fib_table_select_default(struct fib_table *table,
+				     const struct flowi *flp,
+				     struct fib_result *res);
+
+
 #ifndef CONFIG_IP_MULTIPLE_TABLES
 
 #define TABLE_LOCAL_INDEX	0
@@ -182,11 +185,11 @@ static inline int fib_lookup(struct net *net, const struct flowi *flp,
 	struct fib_table *table;
 
 	table = fib_get_table(net, RT_TABLE_LOCAL);
-	if (!table->tb_lookup(table, flp, res))
+	if (!fib_table_lookup(table, flp, res))
 		return 0;
 
 	table = fib_get_table(net, RT_TABLE_MAIN);
-	if (!table->tb_lookup(table, flp, res))
+	if (!fib_table_lookup(table, flp, res))
 		return 0;
 	return -ENETUNREACH;
 }