From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Thu, 18 Mar 2010 11:27:25 +0000 (+0000)
Subject: net: dev_getfirstbyhwtype() optimization
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=99fe3c391d50d381687fd84ed0ab22d57079e41f;p=linux-beck.git

net: dev_getfirstbyhwtype() optimization

Use RCU to avoid RTNL use in dev_getfirstbyhwtype()

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---

diff --git a/net/core/dev.c b/net/core/dev.c
index 2d01f18f303a..a03aab45e84f 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -772,14 +772,17 @@ EXPORT_SYMBOL(__dev_getfirstbyhwtype);
 
 struct net_device *dev_getfirstbyhwtype(struct net *net, unsigned short type)
 {
-	struct net_device *dev;
+	struct net_device *dev, *ret = NULL;
 
-	rtnl_lock();
-	dev = __dev_getfirstbyhwtype(net, type);
-	if (dev)
-		dev_hold(dev);
-	rtnl_unlock();
-	return dev;
+	rcu_read_lock();
+	for_each_netdev_rcu(net, dev)
+		if (dev->type == type) {
+			dev_hold(dev);
+			ret = dev;
+			break;
+		}
+	rcu_read_unlock();
+	return ret;
 }
 EXPORT_SYMBOL(dev_getfirstbyhwtype);