1 | // SPDX-License-Identifier: GPL-2.0 |
2 | // Copyright (c) 2020 Facebook |
3 | |
4 | #include <linux/ptrace.h> |
5 | #include <linux/bpf.h> |
6 | #include <bpf/bpf_helpers.h> |
7 | #include <bpf/bpf_tracing.h> |
8 | |
9 | #define VAR_NUM 2 |
10 | |
11 | struct hmap_elem { |
12 | struct bpf_spin_lock lock; |
13 | int var[VAR_NUM]; |
14 | }; |
15 | |
16 | struct { |
17 | __uint(type, BPF_MAP_TYPE_HASH); |
18 | __uint(max_entries, 1); |
19 | __type(key, __u32); |
20 | __type(value, struct hmap_elem); |
21 | } hash_map SEC(".maps" ); |
22 | |
23 | SEC("freplace/handle_kprobe" ) |
24 | int new_handle_kprobe(struct pt_regs *ctx) |
25 | { |
26 | struct hmap_elem *val; |
27 | int key = 0; |
28 | |
29 | val = bpf_map_lookup_elem(&hash_map, &key); |
30 | if (!val) |
31 | return 1; |
32 | /* spin_lock in hash map */ |
33 | bpf_spin_lock(&val->lock); |
34 | val->var[0] = 99; |
35 | bpf_spin_unlock(&val->lock); |
36 | |
37 | return 0; |
38 | } |
39 | |
40 | char _license[] SEC("license" ) = "GPL" ; |
41 | |