[RFC Patch net-next 6/6] net_sched: switch to RCU API for act_mirred

[Cong Wang]

Signed-off-by: Cong Wang <xiyou.wangc...@gmail.com>
---
 net/sched/act_mirred.c | 41 +++++++++++++++++++----------------------
 1 file changed, 19 insertions(+), 22 deletions(-)

diff --git a/net/sched/act_mirred.c b/net/sched/act_mirred.c
index 6038c85..90a024c 100644
--- a/net/sched/act_mirred.c
+++ b/net/sched/act_mirred.c
@@ -60,6 +60,7 @@ static int tcf_mirred_init(struct net *net, struct nlattr 
*nla,
 {
        struct tc_action_net *tn = net_generic(net, mirred_net_id);
        struct nlattr *tb[TCA_MIRRED_MAX + 1];
+       struct tc_action *n;
        struct tc_mirred *parm;
        struct tcf_mirred *m;
        struct net_device *dev;
@@ -108,44 +109,40 @@ static int tcf_mirred_init(struct net *net, struct nlattr 
*nla,
                        ok_push = 1;
                        break;
                }
-       } else {
-               dev = NULL;
+       } else if (!exists) {
+               return -EINVAL;
+       }
+
+       if (exists && !ovr) {
+               tcf_hash_release(*a, bind);
+               return -EEXIST;
        }
 
-       if (!exists) {
-               if (dev == NULL)
-                       return -EINVAL;
-               ret = tcf_hash_create(tn, parm->index, est, a,
-                                     &act_mirred_ops, bind, true);
-               if (ret)
-                       return ret;
-               ret = ACT_P_CREATED;
-       } else {
+       ret = tcf_hash_create(tn, parm->index, est, &n,
+                             &act_mirred_ops, bind, true);
+       if (ret) {
                tcf_hash_release(*a, bind);
-               if (!ovr)
-                       return -EEXIST;
+               return ret;
        }
-       m = to_mirred(*a);
+
+       tcf_hash_copy(n, *a);
+       m = to_mirred(n);
 
        ASSERT_RTNL();
        m->tcf_action = parm->action;
        m->tcfm_eaction = parm->eaction;
        if (dev != NULL) {
                m->tcfm_ifindex = parm->ifindex;
-               if (ret != ACT_P_CREATED)
-                       dev_put(rcu_dereference_protected(m->tcfm_dev, 1));
                dev_hold(dev);
                rcu_assign_pointer(m->tcfm_dev, dev);
                m->tcfm_ok_push = ok_push;
        }
 
-       if (ret == ACT_P_CREATED) {
-               spin_lock_bh(&mirred_list_lock);
-               list_add(&m->tcfm_list, &mirred_list);
-               spin_unlock_bh(&mirred_list_lock);
-               tcf_hash_insert(tn, *a);
-       }
+       spin_lock_bh(&mirred_list_lock);
+       list_add(&m->tcfm_list, &mirred_list);
+       spin_unlock_bh(&mirred_list_lock);
 
+       tcf_hash_replace(tn, a, n, bind);
        return ret;
 }
 
-- 
2.1.0