Commit 1f821611 authored Jul 30, 2018 by Taehee Yoo Committed by Daniel Borkmann Jul 31, 2018

lwt_bpf: remove unnecessary rcu_read_lock in run_lwt_bpf



run_lwt_bpf is called by bpf_{input/output/xmit}.
These functions are already protected by rcu_read_lock.
because lwtunnel_{input/output/xmit} holds rcu_read_lock
and then calls bpf_{input/output/xmit}.
So that rcu_read_lock in the run_lwt_bpf is unnecessary.

Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

parent 486cdf21

net/core/lwt_bpf.c

+0 −2

Original line number	Original line	Diff line number	Diff line
	@@ -50,10 +50,8 @@ static int run_lwt_bpf(struct sk_buff skb, struct bpf_lwt_prog lwt,
	* mixing with BH RCU lock doesn't work.		* mixing with BH RCU lock doesn't work.
	*/		*/
	preempt_disable();		preempt_disable();
	rcu_read_lock();
	bpf_compute_data_pointers(skb);		bpf_compute_data_pointers(skb);
	ret = bpf_prog_run_save_cb(lwt->prog, skb);		ret = bpf_prog_run_save_cb(lwt->prog, skb);
	rcu_read_unlock();

	switch (ret) {		switch (ret) {
	case BPF_OK:		case BPF_OK:

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