The rcu_read_lock() call in cls_bpf and act_bpf are redundant: on the TX
side, there's already a call to rcu_read_lock_bh() in __dev_queue_xmit(),
and on RX there's a covering rcu_read_lock() in
netif_receive_skb{,_list}_internal().
With the previous patches we also amended the lockdep checks in the map
code to not require any particular RCU flavour, so we can just get rid of
the rcu_read_lock()s.
Signed-off-by: Toke Høiland-Jørgensen <toke@xxxxxxxxxx>
---
net/sched/act_bpf.c | 2 --
net/sched/cls_bpf.c | 3 ---
2 files changed, 5 deletions(-)
diff --git a/net/sched/act_bpf.c b/net/sched/act_bpf.c
index e48e980c3b93..e409a0005717 100644
--- a/net/sched/act_bpf.c
+++ b/net/sched/act_bpf.c
@@ -43,7 +43,6 @@ static int tcf_bpf_act(struct sk_buff *skb, const struct tc_action *act,
tcf_lastuse_update(&prog->tcf_tm);
bstats_cpu_update(this_cpu_ptr(prog->common.cpu_bstats), skb);
- rcu_read_lock();
filter = rcu_dereference(prog->filter);
if (at_ingress) {
__skb_push(skb, skb->mac_len);
@@ -56,7 +55,6 @@ static int tcf_bpf_act(struct sk_buff *skb, const struct tc_action *act,
}
if (skb_sk_is_prefetched(skb) && filter_res != TC_ACT_OK)
skb_orphan(skb);
- rcu_read_unlock();
/* A BPF program may overwrite the default action opcode.
* Similarly as in cls_bpf, if filter_res == -1 we use the
diff --git a/net/sched/cls_bpf.c b/net/sched/cls_bpf.c
index 6e3e63db0e01..fa739efa59f4 100644
--- a/net/sched/cls_bpf.c
+++ b/net/sched/cls_bpf.c
@@ -85,8 +85,6 @@ static int cls_bpf_classify(struct sk_buff *skb, const struct tcf_proto *tp,
struct cls_bpf_prog *prog;
int ret = -1;
- /* Needed here for accessing maps. */
- rcu_read_lock();
list_for_each_entry_rcu(prog, &head->plist, link) {
int filter_res;
@@ -131,7 +129,6 @@ static int cls_bpf_classify(struct sk_buff *skb, const struct tcf_proto *tp,
break;
}
- rcu_read_unlock();
return ret;
}
--
2.32.0
