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1// SPDX-License-Identifier: GPL-2.02#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