openvswitch: Minimize ovs_flow_cmd_del critical section.

ovs_flow_cmd_del() now allocates reply (if needed) after the flow has
already been removed from the flow table.  If the reply allocation
fails, a netlink error is signaled with netlink_set_err(), as is
already done in ovs_flow_cmd_new_or_set() in the similar situation.

Signed-off-by: Jarno Rajahalme <jrajahalme@nicira.com>
Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
This commit is contained in:
Jarno Rajahalme 2014-05-05 14:40:13 -07:00 committed by Pravin B Shelar
parent 0e9796b4af
commit aed067783e

View File

@ -984,50 +984,53 @@ static int ovs_flow_cmd_del(struct sk_buff *skb, struct genl_info *info)
struct sw_flow_match match;
int err;
if (likely(a[OVS_FLOW_ATTR_KEY])) {
ovs_match_init(&match, &key, NULL);
err = ovs_nla_get_match(&match, a[OVS_FLOW_ATTR_KEY], NULL);
if (unlikely(err))
return err;
}
ovs_lock();
dp = get_dp(sock_net(skb->sk), ovs_header->dp_ifindex);
if (!dp) {
if (unlikely(!dp)) {
err = -ENODEV;
goto unlock;
}
if (!a[OVS_FLOW_ATTR_KEY]) {
if (unlikely(!a[OVS_FLOW_ATTR_KEY])) {
err = ovs_flow_tbl_flush(&dp->table);
goto unlock;
}
ovs_match_init(&match, &key, NULL);
err = ovs_nla_get_match(&match, a[OVS_FLOW_ATTR_KEY], NULL);
if (err)
goto unlock;
flow = ovs_flow_tbl_lookup(&dp->table, &key);
if (!flow || !ovs_flow_cmp_unmasked_key(flow, &match)) {
if (unlikely(!flow || !ovs_flow_cmp_unmasked_key(flow, &match))) {
err = -ENOENT;
goto unlock;
}
reply = ovs_flow_cmd_alloc_info(ovsl_dereference(flow->sf_acts), info,
false);
if (IS_ERR(reply)) {
err = PTR_ERR(reply);
goto unlock;
}
ovs_flow_tbl_remove(&dp->table, flow);
if (reply) {
err = ovs_flow_cmd_fill_info(flow, ovs_header->dp_ifindex,
reply, info->snd_portid,
info->snd_seq, 0,
OVS_FLOW_CMD_DEL);
BUG_ON(err < 0);
}
ovs_flow_free(flow, true);
ovs_unlock();
if (reply)
ovs_notify(&dp_flow_genl_family, reply, info);
reply = ovs_flow_cmd_alloc_info((const struct sw_flow_actions __force *) flow->sf_acts,
info, false);
if (likely(reply)) {
if (likely(!IS_ERR(reply))) {
rcu_read_lock(); /*To keep RCU checker happy. */
err = ovs_flow_cmd_fill_info(flow, ovs_header->dp_ifindex,
reply, info->snd_portid,
info->snd_seq, 0,
OVS_FLOW_CMD_DEL);
rcu_read_unlock();
BUG_ON(err < 0);
ovs_notify(&dp_flow_genl_family, reply, info);
} else {
netlink_set_err(sock_net(skb->sk)->genl_sock, 0, 0, PTR_ERR(reply));
}
}
ovs_flow_free(flow, true);
return 0;
unlock:
ovs_unlock();