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1// SPDX-License-Identifier: GPL-2.02#include <linux/bpf.h>3#include <bpf/bpf_helpers.h>4#include "bpf_legacy.h"5 6struct {7 __uint(type, BPF_MAP_TYPE_PROG_ARRAY);8 __uint(max_entries, 1);9 __uint(key_size, sizeof(__u32));10 __uint(value_size, sizeof(__u32));11} jmp_table SEC(".maps");12 13int count = 0;14 15static __noinline16int subprog_tail(struct __sk_buff *skb)17{18 bpf_tail_call_static(skb, &jmp_table, 0);19 return 0;20}21 22SEC("tc")23int entry(struct __sk_buff *skb)24{25 int ret = 1;26 27 count++;28 subprog_tail(skb);29 subprog_tail(skb);30 31 return ret;32}33 34char __license[] SEC("license") = "GPL";35