net_sched: remove useless NULL to tp->root

There is no need to NULL tp->root in ->destroy(), since tp is
going to be freed very soon, and existing readers are still
safe to read them.

For cls_route, we always init its tp->root, so it can't be NULL,
we can drop more useless code.

Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/sched/cls_fw.c b/net/sched/cls_fw.c
index 78ccb4a85a4db1f2bc6758f0db994f6b82206191..d3885362e017e1b477c6c2e4d8abea4b1e021c53 100644 (file)
--- a/net/sched/cls_fw.c
+++ b/net/sched/cls_fw.c
@@ -144,7 +144,6 @@ static void fw_destroy(struct tcf_proto *tp)
                        call_rcu(&f->rcu, fw_delete_filter);
                }
        }
-       RCU_INIT_POINTER(tp->root, NULL);
        kfree_rcu(head, rcu);
 }
 

diff --git a/net/sched/cls_route.c b/net/sched/cls_route.c
index f4d687e0424032df93c57ea3315654758bc4d595..d63d5502ee020350e72b818c5607000a21df915a 100644 (file)
--- a/net/sched/cls_route.c
+++ b/net/sched/cls_route.c
@@ -140,8 +140,6 @@ static int route4_classify(struct sk_buff *skb, const struct tcf_proto *tp,
                goto failure;
 
        id = dst->tclassid;
-       if (head == NULL)
-               goto old_method;
 
        iif = inet_iif(skb);
 
@@ -194,15 +192,6 @@ restart:
                route4_set_fastmap(head, id, iif, ROUTE4_FAILURE);
 failure:
        return -1;
-
-old_method:
-       if (id && (TC_H_MAJ(id) == 0 ||
-                  !(TC_H_MAJ(id^tp->q->handle)))) {
-               res->classid = id;
-               res->class = 0;
-               return 0;
-       }
-       return -1;
 }
 
 static inline u32 to_hash(u32 id)
@@ -234,9 +223,6 @@ static unsigned long route4_get(struct tcf_proto *tp, u32 handle)
        struct route4_filter *f;
        unsigned int h1, h2;
 
-       if (!head)
-               return 0;
-
        h1 = to_hash(handle);
        if (h1 > 256)
                return 0;
@@ -305,7 +291,6 @@ static void route4_destroy(struct tcf_proto *tp)
                        kfree_rcu(b, rcu);
                }
        }
-       RCU_INIT_POINTER(tp->root, NULL);
        kfree_rcu(head, rcu);
 }
 

diff --git a/net/sched/cls_rsvp.h b/net/sched/cls_rsvp.h
index 18a94701617869d674183136b9e69449a0473b6c..0d9d077986992926a79af6236b8840181517679d 100644 (file)
--- a/net/sched/cls_rsvp.h
+++ b/net/sched/cls_rsvp.h
@@ -152,8 +152,6 @@ static int rsvp_classify(struct sk_buff *skb, const struct tcf_proto *tp,
                return -1;
        nhptr = ip_hdr(skb);
 #endif
-       if (unlikely(!head))
-               return -1;
 restart:
 
 #if RSVP_DST_LEN == 4
@@ -310,8 +308,6 @@ static void rsvp_destroy(struct tcf_proto *tp)
        if (data == NULL)
                return;
 
-       RCU_INIT_POINTER(tp->root, NULL);
-
        for (h1 = 0; h1 < 256; h1++) {
                struct rsvp_session *s;