From: Ben Pfaff <blp@nicira.com>
Date: Mon, 21 Jul 2008 18:22:28 +0000 (-0700)
Subject: Properly synchronize dp_dev destruction.
X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=d50ae013a29dceadb205b93bc4c1fbf3c2dea120;p=openvswitch

Properly synchronize dp_dev destruction.

Before, we didn't really synchronize this at all.  Now, when we want
to destroy the ofX device, we stop the transmit path and wait for
in-progress transmissions to finish.
---

diff --git a/datapath/dp_dev.c b/datapath/dp_dev.c
index e618d718..02468eb4 100644
--- a/datapath/dp_dev.c
+++ b/datapath/dp_dev.c
@@ -55,19 +55,16 @@ static int dp_dev_mac_addr(struct net_device *dev, void *p)
 static int dp_dev_xmit(struct sk_buff *skb, struct net_device *netdev)
 {
 	struct dp_dev *dp_dev = dp_dev_priv(netdev);
-	struct datapath *dp;
+	struct datapath *dp = dp_dev->dp;
+
+	dp_dev->stats.tx_packets++;
+	dp_dev->stats.tx_bytes += skb->len;
+
+	skb_reset_mac_header(skb);
 	rcu_read_lock();
-	dp = dp_dev->dp;
-	if (likely(dp != NULL)) {
-		dp_dev->stats.tx_packets++;
-		dp_dev->stats.tx_bytes += skb->len;
-		skb_reset_mac_header(skb);
-		fwd_port_input(dp->chain, skb, OFPP_LOCAL);
-	} else {
-		dp_dev->stats.tx_dropped++;
-		kfree_skb(skb);
-	}
+	fwd_port_input(dp->chain, skb, OFPP_LOCAL);
 	rcu_read_unlock();
+
 	return 0;
 }
 
@@ -127,8 +124,7 @@ int dp_dev_setup(struct datapath *dp)
 
 void dp_dev_destroy(struct datapath *dp)
 {
-	struct dp_dev *dp_dev = dp_dev_priv(dp->netdev);
-	dp_dev->dp = NULL;
+	netif_tx_disable(dp->netdev);
 	synchronize_net();
 	unregister_netdev(dp->netdev);
 	free_netdev(dp->netdev);