1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright (c) 2021 Facebook */
3
4 #include "vmlinux.h"
5 #include <bpf/bpf_helpers.h>
6 #include <bpf/bpf_tracing.h>
7
8 /* modifiers and typedefs are ignored when comparing key/value types */
9 typedef struct my_key { long x; } key_type;
10 typedef struct my_value { long x; } value_type;
11
12 extern struct {
13 __uint(max_entries, 16);
14 __type(key, key_type);
15 __type(value, value_type);
16 __uint(type, BPF_MAP_TYPE_HASH);
17 } map1 SEC(".maps");
18
19 struct {
20 __uint(type, BPF_MAP_TYPE_ARRAY);
21 __type(key, int);
22 __type(value, int);
23 __uint(max_entries, 8);
24 } map2 SEC(".maps");
25
26 /* this definition will lose, but it has to exactly match the winner */
27 struct {
28 __uint(type, BPF_MAP_TYPE_ARRAY);
29 __type(key, int);
30 __type(value, int);
31 __uint(max_entries, 16);
32 } map_weak __weak SEC(".maps");
33
34 int output_first2;
35 int output_second2;
36 int output_weak2;
37
38 SEC("raw_tp/sys_enter")
39 int BPF_PROG(handler_enter2)
40 {
41 /* update values with key = 2 */
42 int key = 2, val = 2;
43 key_type key_struct = { .x = 2 };
44 value_type val_struct = { .x = 2000 };
45
46 bpf_map_update_elem(&map1, &key_struct, &val_struct, 0);
47 bpf_map_update_elem(&map2, &key, &val, 0);
48 bpf_map_update_elem(&map_weak, &key, &val, 0);
49
50 return 0;
51 }
52
53 SEC("raw_tp/sys_exit")
54 int BPF_PROG(handler_exit2)
55 {
56 /* lookup values with key = 1, set in another file */
57 int key = 1, *val;
58 key_type key_struct = { .x = 1 };
59 value_type *value_struct;
60
61 value_struct = bpf_map_lookup_elem(&map1, &key_struct);
62 if (value_struct)
63 output_first2 = value_struct->x;
64
65 val = bpf_map_lookup_elem(&map2, &key);
66 if (val)
67 output_second2 = *val;
68
69 val = bpf_map_lookup_elem(&map_weak, &key);
70 if (val)
71 output_weak2 = *val;
72
73 return 0;
74 }
75
76 char LICENSE[] SEC("license") = "GPL";
77
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.