xref: /openbmc/linux/tools/testing/selftests/bpf/progs/tailcall5.c (revision 79d49ba048ecace59a9850e8a04b618d7848b8e7)
1*79d49ba0SDaniel Borkmann // SPDX-License-Identifier: GPL-2.0
2*79d49ba0SDaniel Borkmann #include <linux/bpf.h>
3*79d49ba0SDaniel Borkmann 
4*79d49ba0SDaniel Borkmann #include "bpf_helpers.h"
5*79d49ba0SDaniel Borkmann 
6*79d49ba0SDaniel Borkmann struct {
7*79d49ba0SDaniel Borkmann 	__uint(type, BPF_MAP_TYPE_PROG_ARRAY);
8*79d49ba0SDaniel Borkmann 	__uint(max_entries, 3);
9*79d49ba0SDaniel Borkmann 	__uint(key_size, sizeof(__u32));
10*79d49ba0SDaniel Borkmann 	__uint(value_size, sizeof(__u32));
11*79d49ba0SDaniel Borkmann } jmp_table SEC(".maps");
12*79d49ba0SDaniel Borkmann 
13*79d49ba0SDaniel Borkmann static volatile int selector;
14*79d49ba0SDaniel Borkmann 
15*79d49ba0SDaniel Borkmann #define TAIL_FUNC(x)				\
16*79d49ba0SDaniel Borkmann 	SEC("classifier/" #x)			\
17*79d49ba0SDaniel Borkmann 	int bpf_func_##x(struct __sk_buff *skb)	\
18*79d49ba0SDaniel Borkmann 	{					\
19*79d49ba0SDaniel Borkmann 		return x;			\
20*79d49ba0SDaniel Borkmann 	}
21*79d49ba0SDaniel Borkmann TAIL_FUNC(0)
22*79d49ba0SDaniel Borkmann TAIL_FUNC(1)
23*79d49ba0SDaniel Borkmann TAIL_FUNC(2)
24*79d49ba0SDaniel Borkmann 
25*79d49ba0SDaniel Borkmann SEC("classifier")
26*79d49ba0SDaniel Borkmann int entry(struct __sk_buff *skb)
27*79d49ba0SDaniel Borkmann {
28*79d49ba0SDaniel Borkmann 	int idx = 0;
29*79d49ba0SDaniel Borkmann 
30*79d49ba0SDaniel Borkmann 	if (selector == 1234)
31*79d49ba0SDaniel Borkmann 		idx = 1;
32*79d49ba0SDaniel Borkmann 	else if (selector == 5678)
33*79d49ba0SDaniel Borkmann 		idx = 2;
34*79d49ba0SDaniel Borkmann 
35*79d49ba0SDaniel Borkmann 	bpf_tail_call(skb, &jmp_table, idx);
36*79d49ba0SDaniel Borkmann 	return 3;
37*79d49ba0SDaniel Borkmann }
38*79d49ba0SDaniel Borkmann 
39*79d49ba0SDaniel Borkmann char __license[] SEC("license") = "GPL";
40*79d49ba0SDaniel Borkmann int _version SEC("version") = 1;
41