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// SPDX-License-Identifier: GPL-2.0
#include <linux/bpf.h>
#include <bpf/bpf_helpers.h>
#include "bpf_misc.h"
int classifier_0(struct __sk_buff *skb);
int classifier_1(struct __sk_buff *skb);
struct {
__uint(type, BPF_MAP_TYPE_PROG_ARRAY);
__uint(max_entries, 2);
__uint(key_size, sizeof(__u32));
__array(values, void (void));
} jmp_table SEC(".maps") = {
.values = {
[0] = (void *) &classifier_0,
[1] = (void *) &classifier_1,
},
};
int count0 = 0;
int count1 = 0;
static __noinline
int subprog_tail0(struct __sk_buff *skb)
{
bpf_tail_call_static(skb, &jmp_table, 0);
return 0;
}
__auxiliary
SEC("tc")
int classifier_0(struct __sk_buff *skb)
{
count0++;
subprog_tail0(skb);
return 0;
}
static __noinline
int subprog_tail1(struct __sk_buff *skb)
{
bpf_tail_call_static(skb, &jmp_table, 1);
return 0;
}
__auxiliary
SEC("tc")
int classifier_1(struct __sk_buff *skb)
{
count1++;
subprog_tail1(skb);
return 0;
}
__success
__retval(33)
SEC("tc")
int tailcall_bpf2bpf_hierarchy_2(struct __sk_buff *skb)
{
int ret = 0;
subprog_tail0(skb);
subprog_tail1(skb);
__sink(ret);
return (count1 << 16) | count0;
}
char __license[] SEC("license") = "GPL";
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