1// SPDX-License-Identifier: GPL-2.0
2
3#include <linux/bpf.h>
4#include <bpf/bpf_helpers.h>
5
6char _license[] SEC("license") = "GPL";
7
8struct {
9 __uint(type, BPF_MAP_TYPE_HASH);
10 __uint(max_entries, 2);
11 __type(key, struct bigelement);
12 __type(value, __u32);
13} hash_map SEC(".maps");
14
15struct {
16 __uint(type, BPF_MAP_TYPE_PERCPU_ARRAY);
17 __uint(max_entries, 1);
18 __type(key, __u32);
19 __type(value, struct bigelement);
20} key_map SEC(".maps");
21
22struct bigelement {
23 int a;
24 char b[4096];
25 long long c;
26};
27
28SEC("raw_tracepoint/sys_enter")
29int bpf_hash_large_key_test(void *ctx)
30{
31 int zero = 0, value = 42;
32 struct bigelement *key;
33
34 key = bpf_map_lookup_elem(&key_map, &zero);
35 if (!key)
36 return 0;
37
38 key->c = 1;
39 if (bpf_map_update_elem(&hash_map, key, &value, BPF_ANY))
40 return 0;
41
42 return 0;
43}
44
45

source code of linux/tools/testing/selftests/bpf/progs/test_hash_large_key.c