ipv4: Avoid overhead when no custom FIB rules are installed.
If the user hasn't actually installed any custom rules, or fiddled
with the default ones, don't go through the whole FIB rules layer.
It's just pure overhead.
Instead do what we do with CONFIG_IP_MULTIPLE_TABLES disabled, check
the individual tables by hand, one by one.
Also, move fib_num_tclassid_users into the ipv4 network namespace.
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/fib_frontend.c b/net/ipv4/fib_frontend.c
index 3e11ea2..81f8571 100644
--- a/net/ipv4/fib_frontend.c
+++ b/net/ipv4/fib_frontend.c
@@ -86,6 +86,24 @@
tb = fib_trie_table(id);
if (!tb)
return NULL;
+
+ switch (id) {
+ case RT_TABLE_LOCAL:
+ net->ipv4.fib_local = tb;
+ break;
+
+ case RT_TABLE_MAIN:
+ net->ipv4.fib_main = tb;
+ break;
+
+ case RT_TABLE_DEFAULT:
+ net->ipv4.fib_default = tb;
+ break;
+
+ default:
+ break;
+ }
+
h = id & (FIB_TABLE_HASHSZ - 1);
hlist_add_head_rcu(&tb->tb_hlist, &net->ipv4.fib_table_hash[h]);
return tb;
@@ -218,10 +236,6 @@
return inet_select_addr(dev, ip_hdr(skb)->saddr, scope);
}
-#ifdef CONFIG_IP_ROUTE_CLASSID
-int fib_num_tclassid_users __read_mostly;
-#endif
-
/* Given (packet source, input interface) and optional (dst, oif, tos):
* - (main) check, that source is valid i.e. not broadcast or our local
* address.
@@ -312,7 +326,7 @@
{
int r = secpath_exists(skb) ? 0 : IN_DEV_RPFILTER(idev);
- if (!r && !fib_num_tclassid_users) {
+ if (!r && !fib_num_tclassid_users(dev_net(dev))) {
*itag = 0;
return 0;
}
@@ -1134,6 +1148,9 @@
{
int error;
+#ifdef CONFIG_IP_ROUTE_CLASSID
+ net->ipv4.fib_num_tclassid_users = 0;
+#endif
error = ip_fib_net_init(net);
if (error < 0)
goto out;