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| author |   David S. Miller <davem@davemloft.net> | 2012-06-29 01:32:45 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2012-06-29 01:36:36 -0700 |
| commit | 7a9bc9b81a5bc6e44ebc80ef781332e4385083f2 (patch) | |
| tree | 1342c672823d47bfb112fee63951af9f6a3eb590 /net/ipv4/fib_rules.c | |
| parent | net: l2tp_eth: provide tx_dropped counter (diff) | |
| download | linux-dev-7a9bc9b81a5bc6e44ebc80ef781332e4385083f2.tar.xz linux-dev-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 'net/ipv4/fib_rules.c')
| -rw-r--r-- | net/ipv4/fib_rules.c | 16 |
1 files changed, 15 insertions, 1 deletions
diff --git a/net/ipv4/fib_rules.c b/net/ipv4/fib_rules.c index 2d043f71ef70..b23fd952c84f 100644 --- a/net/ipv4/fib_rules.c +++ b/net/ipv4/fib_rules.c @@ -169,8 +169,11 @@ static int fib4_rule_configure(struct fib_rule *rule, struct sk_buff *skb, rule4->dst = nla_get_be32(tb[FRA_DST]); #ifdef CONFIG_IP_ROUTE_CLASSID - if (tb[FRA_FLOW]) + if (tb[FRA_FLOW]) { rule4->tclassid = nla_get_u32(tb[FRA_FLOW]); + if (rule4->tclassid) + fib_num_tclassid_users++; + } #endif rule4->src_len = frh->src_len; @@ -184,6 +187,16 @@ errout: return err; } +static void fib4_rule_delete(struct fib_rule *rule) +{ +#ifdef CONFIG_IP_ROUTE_CLASSID + struct fib4_rule *rule4 = (struct fib4_rule *) rule; + + if (rule4->tclassid) + fib_num_tclassid_users--; +#endif +} + static int fib4_rule_compare(struct fib_rule *rule, struct fib_rule_hdr *frh, struct nlattr **tb) { @@ -256,6 +269,7 @@ static const struct fib_rules_ops __net_initdata fib4_rules_ops_template = { .action = fib4_rule_action, .match = fib4_rule_match, .configure = fib4_rule_configure, + .delete = fib4_rule_delete, .compare = fib4_rule_compare, .fill = fib4_rule_fill, .default_pref = fib_default_rule_pref, |