diff options
| author | Andy Zhou <azhou@nicira.com> | 2014-07-15 14:38:29 -0700 |
|---|---|---|
| committer | Andy Zhou <azhou@nicira.com> | 2014-07-22 15:49:37 -0700 |
| commit | 01ac0970c80ab08480b9ec169356f55d0f3c0c4a (patch) | |
| tree | 27499eead0f945800e29c32c7d9e65c034dc965b | |
| parent | 368a198a536809139f13fccc8fbbf75837c5653d (diff) | |
| download | openvswitch-01ac0970c80ab08480b9ec169356f55d0f3c0c4a.tar.gz | |
datapath: Refactor get_dp() function into multiple access APIs.
Avoid recursive read_rcu_lock() by using the lighter weight get_dp_rcu()
API. Add proper locking assertions to get_dp().
Signed-off-by: Andy Zhou <azhou@nicira.com>
Acked-by: Pravin B Shelar <pshelar@nicira.com>
| -rw-r--r-- | datapath/datapath.c | 30 |
1 files changed, 20 insertions, 10 deletions
diff --git a/datapath/datapath.c b/datapath/datapath.c index 065356fea..94539ebff 100644 --- a/datapath/datapath.c +++ b/datapath/datapath.c @@ -140,19 +140,29 @@ static int queue_gso_packets(struct datapath *dp, struct sk_buff *, static int queue_userspace_packet(struct datapath *dp, struct sk_buff *, const struct dp_upcall_info *); -/* Must be called with rcu_read_lock or ovs_mutex. */ -static struct datapath *get_dp(struct net *net, int dp_ifindex) +/* Must be called with rcu_read_lock. */ +static struct datapath *get_dp_rcu(struct net *net, int dp_ifindex) { - struct datapath *dp = NULL; - struct net_device *dev; + struct net_device *dev = dev_get_by_index_rcu(net, dp_ifindex); - rcu_read_lock(); - dev = dev_get_by_index_rcu(net, dp_ifindex); if (dev) { struct vport *vport = ovs_internal_dev_get_vport(dev); if (vport) - dp = vport->dp; + return vport->dp; } + + return NULL; +} + +/* The caller must hold either ovs_mutex or rcu_read_lock to keep the + * returned dp pointer valid. */ +static inline struct datapath *get_dp(struct net *net, int dp_ifindex) +{ + struct datapath *dp; + + WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_ovsl_is_held()); + rcu_read_lock(); + dp = get_dp_rcu(net, dp_ifindex); rcu_read_unlock(); return dp; @@ -595,7 +605,7 @@ static int ovs_packet_cmd_execute(struct sk_buff *skb, struct genl_info *info) packet->mark = flow->key.phy.skb_mark; rcu_read_lock(); - dp = get_dp(sock_net(skb->sk), ovs_header->dp_ifindex); + dp = get_dp_rcu(sock_net(skb->sk), ovs_header->dp_ifindex); err = -ENODEV; if (!dp) goto err_unlock; @@ -1252,7 +1262,7 @@ static int ovs_flow_cmd_dump(struct sk_buff *skb, struct netlink_callback *cb) struct datapath *dp; rcu_read_lock(); - dp = get_dp(sock_net(skb->sk), ovs_header->dp_ifindex); + dp = get_dp_rcu(sock_net(skb->sk), ovs_header->dp_ifindex); if (!dp) { rcu_read_unlock(); return -ENODEV; @@ -2019,7 +2029,7 @@ static int ovs_vport_cmd_dump(struct sk_buff *skb, struct netlink_callback *cb) int i, j = 0; rcu_read_lock(); - dp = get_dp(sock_net(skb->sk), ovs_header->dp_ifindex); + dp = get_dp_rcu(sock_net(skb->sk), ovs_header->dp_ifindex); if (!dp) { rcu_read_unlock(); return -ENODEV; |