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") 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 __u32 _version SEC("version") = 1; /* ignored by tracepoints, required by libbpf.a */ 41