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// SPDX-License-Identifier: GPL-2.0
/* Copyright Leon Hwang */
#include "vmlinux.h"
#include <bpf/bpf_helpers.h>
#include <bpf/bpf_tracing.h>
struct {
__uint(type, BPF_MAP_TYPE_PROG_ARRAY);
__uint(max_entries, 1);
__uint(key_size, sizeof(__u32));
__uint(value_size, sizeof(__u32));
} jmp_table SEC(".maps");
int count = 0;
static __noinline
int subprog_tail(void *ctx)
{
bpf_tail_call_static(ctx, &jmp_table, 0);
return 0;
}
SEC("fentry/dummy")
int BPF_PROG(fentry, struct sk_buff *skb)
{
count++;
subprog_tail(ctx);
subprog_tail(ctx);
return 0;
}
char _license[] SEC("license") = "GPL";
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