From: stephen hemminger <shemminger@vyatta.com>
Date: Mon, 4 Apr 2011 14:03:29 +0000 (+0000)
Subject: bridge: split rcu and no-rcu cases of fdb lookup
X-Git-Tag: v3.12-rc1~5334^2~689
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=664de48bb6c4e167fcdf92a4bddf880030fbfbb3;p=kernel%2Fkernel-generic.git

bridge: split rcu and no-rcu cases of fdb lookup

In some cases, look up of forward database entry is done with RCU;
and for others no RCU is needed because of locking. Split the two
cases into two differnt loops (and take off inline).

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

diff --git a/net/bridge/br_fdb.c b/net/bridge/br_fdb.c
index b391352..a839a5d 100644
--- a/net/bridge/br_fdb.c
+++ b/net/bridge/br_fdb.c
@@ -305,8 +305,21 @@ int br_fdb_fillbuf(struct net_bridge *br, void *buf,
 	return num;
 }
 
-static inline struct net_bridge_fdb_entry *fdb_find(struct hlist_head *head,
-						    const unsigned char *addr)
+static struct net_bridge_fdb_entry *fdb_find(struct hlist_head *head,
+					     const unsigned char *addr)
+{
+	struct hlist_node *h;
+	struct net_bridge_fdb_entry *fdb;
+
+	hlist_for_each_entry(fdb, h, head, hlist) {
+		if (!compare_ether_addr(fdb->addr.addr, addr))
+			return fdb;
+	}
+	return NULL;
+}
+
+static struct net_bridge_fdb_entry *fdb_find_rcu(struct hlist_head *head,
+						 const unsigned char *addr)
 {
 	struct hlist_node *h;
 	struct net_bridge_fdb_entry *fdb;
@@ -393,7 +406,7 @@ void br_fdb_update(struct net_bridge *br, struct net_bridge_port *source,
 	      source->state == BR_STATE_FORWARDING))
 		return;
 
-	fdb = fdb_find(head, addr);
+	fdb = fdb_find_rcu(head, addr);
 	if (likely(fdb)) {
 		/* attempt to update an entry for a local interface */
 		if (unlikely(fdb->is_local)) {