Re: [PATCH] Ipv6: Delete rcu_read_lock
flat view
From: Eric Dumazet <hidden>
Date: 2011-09-29 08:44:08
Subsystem:
networking [general], networking [ipv4/ipv6], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, David Ahern, Ido Schimmel, Linus Torvalds
Le jeudi 29 septembre 2011 à 15:46 +0800, rongqing.li@windriver.com a écrit :
From: Roy.Li <redacted> Delete rcu_read_lock, it is redundant.
A good changelog and patch title are required. Something like : [PATCH net-next] ipv6: remove a rcu_read_lock in ndisc_constructor in6_dev_get(dev) takes a reference on struct inet6_dev, we dont need rcu locking in ndisc_constructor() ----- Or, you could try to really use RCU and not take a reference (ie, use __in6_dev_get() instead of in6_dev_get(dev). Untested patch :
diff --git a/net/ipv6/ndisc.c b/net/ipv6/ndisc.c
index 9da6e02..a4f4472 100644
--- a/net/ipv6/ndisc.c
+++ b/net/ipv6/ndisc.c@@ -371,7 +371,7 @@ static int ndisc_constructor(struct neighbour *neigh) int is_multicast = ipv6_addr_is_multicast(addr); rcu_read_lock(); - in6_dev = in6_dev_get(dev); + in6_dev = __in6_dev_get(dev); if (in6_dev == NULL) { rcu_read_unlock(); return -EINVAL;
@@ -380,7 +380,6 @@ static int ndisc_constructor(struct neighbour *neigh) parms = in6_dev->nd_parms; __neigh_parms_put(neigh->parms); neigh->parms = neigh_parms_clone(parms); - rcu_read_unlock(); neigh->type = is_multicast ? RTN_MULTICAST : RTN_UNICAST; if (!dev->header_ops) {
@@ -409,7 +408,7 @@ static int ndisc_constructor(struct neighbour *neigh) else neigh->output = neigh->ops->output; } - in6_dev_put(in6_dev); + rcu_read_unlock(); return 0; }