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39#include <linux/bpf.h>
#include <bpf/bpf_helpers.h>
#define __unused __attribute__((unused))
char __license[] SEC("license") = "GPL";
struct {
__uint(type, BPF_MAP_TYPE_PROG_ARRAY);
__uint(max_entries, 1);
__uint(key_size, sizeof(__u32));
__uint(value_size, sizeof(__u32));
} bar SEC(".maps");
SEC("tc")
int barista(struct __sk_buff *skb __unused)
{
return 0xcafe;
}
static __noinline
int bring_order(struct __sk_buff *skb)
{
bpf_tail_call(skb, &bar, 0);
return 0xf00d;
}
SEC("tc")
int server1(struct __sk_buff *skb)
{
return bring_order(skb);
}
SEC("tc")
int server2(struct __sk_buff *skb)
{
__attribute__((musttail)) return bring_order(skb);
}