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| author | David S. Miller <davem@davemloft.net> | 2012-06-29 10:32:45 +0200 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2012-06-29 10:36:36 +0200 |
| commit | 7a9bc9b81a5bc6e44ebc80ef781332e4385083f2 (patch) | |
| tree | 1342c672823d47bfb112fee63951af9f6a3eb590 /include/net/ip_fib.h | |
| parent | net: l2tp_eth: provide tx_dropped counter (diff) | |
| download | linux-7a9bc9b81a5bc6e44ebc80ef781332e4385083f2.tar.xz linux-7a9bc9b81a5bc6e44ebc80ef781332e4385083f2.zip | |
ipv4: Elide fib_validate_source() completely when possible.
If rpfilter is off (or the SKB has an IPSEC path) and there are not
tclassid users, we don't have to do anything at all when
fib_validate_source() is invoked besides setting the itag to zero.
We monitor tclassid uses with a counter (modified only under RTNL and
marked __read_mostly) and we protect the fib_validate_source() real
work with a test against this counter and whether rpfilter is to be
done.
Having a way to know whether we need no tclassid processing or not
also opens the door for future optimized rpfilter algorithms that do
not perform full FIB lookups.
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include/net/ip_fib.h')
| -rw-r--r-- | include/net/ip_fib.h | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/include/net/ip_fib.h b/include/net/ip_fib.h index 619f68a7185c..3dc7c96bbeab 100644 --- a/include/net/ip_fib.h +++ b/include/net/ip_fib.h @@ -235,6 +235,11 @@ extern int fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst, u8 tos, int oif, struct net_device *dev, struct in_device *idev, u32 *itag); extern void fib_select_default(struct fib_result *res); +#ifdef CONFIG_IP_ROUTE_CLASSID +extern int fib_num_tclassid_users; +#else +#define fib_num_tclassid_users 0 +#endif /* Exported by fib_semantics.c */ extern int ip_fib_check_default(__be32 gw, struct net_device *dev); |