net: bridge: fdb: eliminate extra port state tests from fast-path

When commit df1c0b8468 ("[BRIDGE]: Packets leaking out of
disabled/blocked ports.") introduced the port state tests in
br_fdb_update() it was to avoid learning/refreshing from STP BPDUs, it was
also used to avoid learning/refreshing from user-space with NTF_USE. Those
two tests are done for every packet entering the bridge if it's learning,
but for the fast-path we already have them checked in br_handle_frame() and
is unnecessary to do it again. Thus push the checks to the unlikely cases
and drop them from br_fdb_update(), the new nbp_state_should_learn() helper
is used to determine if the port state allows br_fdb_update() to be called.
The two places which need to do it manually are:
 - user-space add call with NTF_USE set
 - link-local packet learning done in __br_handle_local_finish()

Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Nikolay Aleksandrov 2019-11-04 11:36:51 +02:00 committed by David S. Miller
parent 1574cf83c7
commit 5d1fcaf35d
3 changed files with 9 additions and 5 deletions

View File

@ -566,11 +566,6 @@ void br_fdb_update(struct net_bridge *br, struct net_bridge_port *source,
if (hold_time(br) == 0) if (hold_time(br) == 0)
return; return;
/* ignore packets unless we are using this port */
if (!(source->state == BR_STATE_LEARNING ||
source->state == BR_STATE_FORWARDING))
return;
fdb = fdb_find_rcu(&br->fdb_hash_tbl, addr, vid); fdb = fdb_find_rcu(&br->fdb_hash_tbl, addr, vid);
if (likely(fdb)) { if (likely(fdb)) {
/* attempt to update an entry for a local interface */ /* attempt to update an entry for a local interface */
@ -886,6 +881,9 @@ static int __br_fdb_add(struct ndmsg *ndm, struct net_bridge *br,
br->dev->name); br->dev->name);
return -EINVAL; return -EINVAL;
} }
if (!nbp_state_should_learn(p))
return 0;
local_bh_disable(); local_bh_disable();
rcu_read_lock(); rcu_read_lock();
br_fdb_update(br, p, addr, vid, BIT(BR_FDB_ADDED_BY_USER)); br_fdb_update(br, p, addr, vid, BIT(BR_FDB_ADDED_BY_USER));

View File

@ -182,6 +182,7 @@ static void __br_handle_local_finish(struct sk_buff *skb)
/* check if vlan is allowed, to avoid spoofing */ /* check if vlan is allowed, to avoid spoofing */
if ((p->flags & BR_LEARNING) && if ((p->flags & BR_LEARNING) &&
nbp_state_should_learn(p) &&
!br_opt_get(p->br, BROPT_NO_LL_LEARN) && !br_opt_get(p->br, BROPT_NO_LL_LEARN) &&
br_should_learn(p, skb, &vid)) br_should_learn(p, skb, &vid))
br_fdb_update(p->br, p, eth_hdr(skb)->h_source, vid, 0); br_fdb_update(p->br, p, eth_hdr(skb)->h_source, vid, 0);

View File

@ -500,6 +500,11 @@ static inline bool br_vlan_should_use(const struct net_bridge_vlan *v)
return true; return true;
} }
static inline bool nbp_state_should_learn(const struct net_bridge_port *p)
{
return p->state == BR_STATE_LEARNING || p->state == BR_STATE_FORWARDING;
}
static inline int br_opt_get(const struct net_bridge *br, static inline int br_opt_get(const struct net_bridge *br,
enum net_bridge_opts opt) enum net_bridge_opts opt)
{ {