1// SPDX-License-Identifier: GPL-2.0
2#include <linux/bpf.h>
3
4#include <bpf/bpf_helpers.h>
5
6struct {
7	__uint(type, BPF_MAP_TYPE_PROG_ARRAY);
8	__uint(max_entries, 5);
9	__uint(key_size, sizeof(__u32));
10	__uint(value_size, sizeof(__u32));
11} jmp_table SEC(".maps");
12
13SEC("tc")
14int classifier_0(struct __sk_buff *skb)
15{
16	bpf_tail_call_static(skb, &jmp_table, 1);
17	return 0;
18}
19
20SEC("tc")
21int classifier_1(struct __sk_buff *skb)
22{
23	bpf_tail_call_static(skb, &jmp_table, 2);
24	return 1;
25}
26
27SEC("tc")
28int classifier_2(struct __sk_buff *skb)
29{
30	return 2;
31}
32
33SEC("tc")
34int classifier_3(struct __sk_buff *skb)
35{
36	bpf_tail_call_static(skb, &jmp_table, 4);
37	return 3;
38}
39
40SEC("tc")
41int classifier_4(struct __sk_buff *skb)
42{
43	bpf_tail_call_static(skb, &jmp_table, 3);
44	return 4;
45}
46
47SEC("tc")
48int entry(struct __sk_buff *skb)
49{
50	bpf_tail_call_static(skb, &jmp_table, 0);
51	/* Check multi-prog update. */
52	bpf_tail_call_static(skb, &jmp_table, 2);
53	/* Check tail call limit. */
54	bpf_tail_call_static(skb, &jmp_table, 3);
55	return 3;
56}
57
58char __license[] SEC("license") = "GPL";
59