[ovs-dev] [PATCH 08/12] datapath: Convert rcu_dereference() to correct variant.
Jesse Gross
jesse at nicira.com
Sun Dec 12 20:53:03 UTC 2010
Using rcu_dereference() makes lockdep complain if rcu_read_lock
is not held. This is OK if the update side lock is held. This
adds checks to see if RTNL lock is held, if that is also a
correct form of protection.
Signed-off-by: Jesse Gross <jesse at nicira.com>
---
datapath/tunnel.c | 8 ++++----
datapath/vport-netdev.c | 4 ++--
datapath/vport-patch.c | 7 ++++---
3 files changed, 10 insertions(+), 9 deletions(-)
diff --git a/datapath/tunnel.c b/datapath/tunnel.c
index 4873e19..395cf6c 100644
--- a/datapath/tunnel.c
+++ b/datapath/tunnel.c
@@ -181,7 +181,7 @@ static int port_cmp(const struct tbl_node *node, void *target)
const struct tnl_vport *tnl_vport = tnl_vport_table_cast(node);
struct port_lookup_key *lookup = target;
- lookup->mutable = rcu_dereference(tnl_vport->mutable);
+ lookup->mutable = rcu_dereference_rtnl(tnl_vport->mutable);
return (lookup->mutable->tunnel_type == lookup->tunnel_type &&
lookup->mutable->port_config.daddr == lookup->daddr &&
@@ -313,7 +313,7 @@ struct vport *tnl_find_port(__be32 saddr, __be32 daddr, __be64 key,
const struct tnl_mutable_config **mutable)
{
struct port_lookup_key lookup;
- struct tbl *table = rcu_dereference(port_table);
+ struct tbl *table = rcu_dereference_rtnl(port_table);
struct tbl_node *tbl_node;
if (unlikely(!table))
@@ -1511,13 +1511,13 @@ const char *tnl_get_name(const struct vport *vport)
const unsigned char *tnl_get_addr(const struct vport *vport)
{
const struct tnl_vport *tnl_vport = tnl_vport_priv(vport);
- return rcu_dereference(tnl_vport->mutable)->eth_addr;
+ return rcu_dereference_rtnl(tnl_vport->mutable)->eth_addr;
}
int tnl_get_mtu(const struct vport *vport)
{
const struct tnl_vport *tnl_vport = tnl_vport_priv(vport);
- return rcu_dereference(tnl_vport->mutable)->mtu;
+ return rcu_dereference_rtnl(tnl_vport->mutable)->mtu;
}
void tnl_free_linked_skbs(struct sk_buff *skb)
diff --git a/datapath/vport-netdev.c b/datapath/vport-netdev.c
index 8827473..d492d19 100644
--- a/datapath/vport-netdev.c
+++ b/datapath/vport-netdev.c
@@ -279,11 +279,11 @@ struct vport *netdev_get_vport(struct net_device *dev)
#else
if (likely(rcu_access_pointer(dev->rx_handler) == netdev_frame_hook))
#endif
- return (struct vport *)rcu_dereference(dev->rx_handler_data);
+ return (struct vport *)rcu_dereference_rtnl(dev->rx_handler_data);
else
return NULL;
#else
- return (struct vport *)rcu_dereference(dev->br_port);
+ return (struct vport *)rcu_dereference_rtnl(dev->br_port);
#endif
}
diff --git a/datapath/vport-patch.c b/datapath/vport-patch.c
index 8bb204b..4fdbcf5 100644
--- a/datapath/vport-patch.c
+++ b/datapath/vport-patch.c
@@ -9,6 +9,7 @@
#include <linux/dcache.h>
#include <linux/kernel.h>
#include <linux/list.h>
+#include <linux/rtnetlink.h>
#include "datapath.h"
#include "vport.h"
@@ -58,7 +59,7 @@ static void assign_config_rcu(struct vport *vport,
struct patch_vport *patch_vport = patch_vport_priv(vport);
struct device_config *old_config;
- old_config = rcu_dereference(patch_vport->devconf);
+ old_config = rtnl_dereference(patch_vport->devconf);
rcu_assign_pointer(patch_vport->devconf, new_config);
call_rcu(&old_config->rcu, free_config);
}
@@ -228,13 +229,13 @@ static const char *patch_get_name(const struct vport *vport)
static const unsigned char *patch_get_addr(const struct vport *vport)
{
const struct patch_vport *patch_vport = patch_vport_priv(vport);
- return rcu_dereference(patch_vport->devconf)->eth_addr;
+ return rcu_dereference_rtnl(patch_vport->devconf)->eth_addr;
}
static int patch_get_mtu(const struct vport *vport)
{
const struct patch_vport *patch_vport = patch_vport_priv(vport);
- return rcu_dereference(patch_vport->devconf)->mtu;
+ return rcu_dereference_rtnl(patch_vport->devconf)->mtu;
}
static int patch_send(struct vport *vport, struct sk_buff *skb)
--
1.7.1
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