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| author | Andy Zhou <azhou@nicira.com> | 2014-09-08 13:14:22 -0700 |
|---|---|---|
| committer | Pravin B Shelar <pshelar@nicira.com> | 2014-11-05 23:52:34 -0800 |
| commit | cc3a5ae6f23336ddc1d136a66c0a6a60276e99a3 (patch) | |
| tree | 6c3af8e0e35ca25c331659a7f6c5c057158ba1d4 /net/openvswitch | |
| parent | ca7105f278b3f7bd2c6f2b336c928f679054de4d (diff) | |
| download | linux-cc3a5ae6f23336ddc1d136a66c0a6a60276e99a3.tar.bz2 | |
openvswitch: 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>
Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Diffstat (limited to 'net/openvswitch')
| -rw-r--r-- | net/openvswitch/datapath.c | 31 |
1 files changed, 21 insertions, 10 deletions
diff --git a/net/openvswitch/datapath.c b/net/openvswitch/datapath.c index bbb920bf48da..cdbc44c18714 100644 --- a/net/openvswitch/datapath.c +++ b/net/openvswitch/datapath.c @@ -140,19 +140,30 @@ 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; @@ -573,7 +584,7 @@ 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; @@ -1227,7 +1238,7 @@ 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; @@ -1989,7 +2000,7 @@ 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; |