1 // SPDX-License-Identifier: GPL-2.0
2 // Copyright (c) 2018 Facebook
3
4 #include <linux/bpf.h>
5 #include <bpf/bpf_helpers.h>
6
7 struct {
8 __uint(type, BPF_MAP_TYPE_ARRAY);
9 __uint(max_entries, 1);
10 __type(key, __u32);
11 __type(value, __u64);
12 } cg_ids SEC(".maps");
13
14 struct {
15 __uint(type, BPF_MAP_TYPE_ARRAY);
16 __uint(max_entries, 1);
17 __type(key, __u32);
18 __type(value, __u32);
19 } pidmap SEC(".maps");
20
21 SEC("tracepoint/syscalls/sys_enter_nanosleep")
trace(void * ctx)22 int trace(void *ctx)
23 {
24 __u32 pid = bpf_get_current_pid_tgid();
25 __u32 key = 0, *expected_pid;
26 __u64 *val;
27
28 expected_pid = bpf_map_lookup_elem(&pidmap, &key);
29 if (!expected_pid || *expected_pid != pid)
30 return 0;
31
32 val = bpf_map_lookup_elem(&cg_ids, &key);
33 if (val)
34 *val = bpf_get_current_cgroup_id();
35
36 return 0;
37 }
38
39 char _license[] SEC("license") = "GPL";
40