1#include <linux/ptrace.h>
 2#include <linux/version.h>
 3#include <uapi/linux/bpf.h>
 4#include <bpf/bpf_helpers.h>
 5
 6struct {
 7	__uint(type, BPF_MAP_TYPE_PERF_EVENT_ARRAY);
 8	__uint(key_size, sizeof(int));
 9	__uint(value_size, sizeof(u32));
10	__uint(max_entries, 64);
11} counters SEC(".maps");
12
13struct {
14	__uint(type, BPF_MAP_TYPE_HASH);
15	__type(key, int);
16	__type(value, u64);
17	__uint(max_entries, 64);
18} values SEC(".maps");
19
20struct {
21	__uint(type, BPF_MAP_TYPE_HASH);
22	__type(key, int);
23	__type(value, struct bpf_perf_event_value);
24	__uint(max_entries, 64);
25} values2 SEC(".maps");
26
27SEC("kprobe/htab_map_get_next_key")
28int bpf_prog1(struct pt_regs *ctx)
29{
30	u32 key = bpf_get_smp_processor_id();
31	u64 count, *val;
32	s64 error;
33
34	count = bpf_perf_event_read(&counters, key);
35	error = (s64)count;
36	if (error <= -2 && error >= -22)
37		return 0;
38
39	val = bpf_map_lookup_elem(&values, &key);
40	if (val)
41		*val = count;
42	else
43		bpf_map_update_elem(&values, &key, &count, BPF_NOEXIST);
44
45	return 0;
46}
47
48SEC("kprobe/htab_map_lookup_elem")
49int bpf_prog2(struct pt_regs *ctx)
50{
51	u32 key = bpf_get_smp_processor_id();
52	struct bpf_perf_event_value *val, buf;
53	int error;
54
55	error = bpf_perf_event_read_value(&counters, key, &buf, sizeof(buf));
56	if (error)
57		return 0;
58
59	val = bpf_map_lookup_elem(&values2, &key);
60	if (val)
61		*val = buf;
62	else
63		bpf_map_update_elem(&values2, &key, &buf, BPF_NOEXIST);
64
65	return 0;
66}
67
68char _license[] SEC("license") = "GPL";
69u32 _version SEC("version") = LINUX_VERSION_CODE;