Cong Wang <xiyou.wangc...@gmail.com> writes:
[...]
> static void cls_cgroup_destroy_work(struct work_struct *work)
> {
> struct cls_cgroup_head *head = container_of(work,
> struct cls_cgroup_head,
> work);
> rtnl_lock();
> - tcf_exts_destroy(&head->exts);
> - tcf_em_tree_destroy(&head->ematches);
> - kfree(head);
> + __cls_cgroup_destroy(head);
> rtnl_unlock();
> }
>
> @@ -124,8 +130,10 @@ static int cls_cgroup_change(struct net *net, struct
> sk_buff *in_skb,
> goto errout;
>
> rcu_assign_pointer(tp->root, new);
> - if (head)
> + if (head) {
> + tcf_exts_get_net(&head->exts);
> call_rcu(&head->rcu, cls_cgroup_destroy_rcu);
In this case why do you not need to care about success/failure of
tcf_exts_get_net() ?
> + }
> return 0;
> errout:
> tcf_exts_destroy(&new->exts);
> @@ -138,8 +146,12 @@ static void cls_cgroup_destroy(struct tcf_proto *tp)
> struct cls_cgroup_head *head = rtnl_dereference(tp->root);
>
> /* Head can still be NULL due to cls_cgroup_init(). */
> - if (head)
> - call_rcu(&head->rcu, cls_cgroup_destroy_rcu);
> + if (head) {
> + if (tcf_exts_get_net(&head->exts))
> + call_rcu(&head->rcu, cls_cgroup_destroy_rcu);
> + else
> + __cls_cgroup_destroy(head);
> + }
> }
>
> static int cls_cgroup_delete(struct tcf_proto *tp, void *arg, bool *last)
