From 65b2a02a9b576d824f47de43024659623baab6a3 Mon Sep 17 00:00:00 2001
From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Thu, 19 Aug 2010 06:10:45 +0000
Subject: [PATCH] --- yaml --- r: 213893 b: refs/heads/master c:
 49e8ab03ebcacd8e37660ffec20c0c46721a2800 h: refs/heads/master i:   213891:
 e376a22069ac2f90a800505e8acc8d187c40f974 v: v3

---
 [refs]                   | 2 +-
 trunk/net/ipv4/af_inet.c | 8 +++-----
 trunk/net/ipv4/route.c   | 9 +--------
 3 files changed, 5 insertions(+), 14 deletions(-)

diff --git a/[refs] b/[refs]
index a2c3a504c3ce..6fc4aa002cb9 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 4da79504b2b41410dd56e9268c9ad403aa65e89c
+refs/heads/master: 49e8ab03ebcacd8e37660ffec20c0c46721a2800
diff --git a/trunk/net/ipv4/af_inet.c b/trunk/net/ipv4/af_inet.c
index 6a1100c25a9f..f581f77d1097 100644
--- a/trunk/net/ipv4/af_inet.c
+++ b/trunk/net/ipv4/af_inet.c
@@ -227,18 +227,16 @@ EXPORT_SYMBOL(inet_ehash_secret);
 
 /*
  * inet_ehash_secret must be set exactly once
- * Instead of using a dedicated spinlock, we (ab)use inetsw_lock
  */
 void build_ehash_secret(void)
 {
 	u32 rnd;
+
 	do {
 		get_random_bytes(&rnd, sizeof(rnd));
 	} while (rnd == 0);
-	spin_lock_bh(&inetsw_lock);
-	if (!inet_ehash_secret)
-		inet_ehash_secret = rnd;
-	spin_unlock_bh(&inetsw_lock);
+
+	cmpxchg(&inet_ehash_secret, 0, rnd);
 }
 EXPORT_SYMBOL(build_ehash_secret);
 
diff --git a/trunk/net/ipv4/route.c b/trunk/net/ipv4/route.c
index 3f56b6e6c6aa..85a67c9d5982 100644
--- a/trunk/net/ipv4/route.c
+++ b/trunk/net/ipv4/route.c
@@ -1268,18 +1268,11 @@ static int rt_intern_hash(unsigned hash, struct rtable *rt,
 
 void rt_bind_peer(struct rtable *rt, int create)
 {
-	static DEFINE_SPINLOCK(rt_peer_lock);
 	struct inet_peer *peer;
 
 	peer = inet_getpeer(rt->rt_dst, create);
 
-	spin_lock_bh(&rt_peer_lock);
-	if (rt->peer == NULL) {
-		rt->peer = peer;
-		peer = NULL;
-	}
-	spin_unlock_bh(&rt_peer_lock);
-	if (peer)
+	if (peer && cmpxchg(&rt->peer, NULL, peer) != NULL)
 		inet_putpeer(peer);
 }