// SPDX-License-Identifier: GPL-2.0 // Copyright (c) 2018 Facebook #include <linux/bpf.h> #include "bpf_helpers.h" struct bpf_map_def SEC("maps") cg_ids = { .type = BPF_MAP_TYPE_ARRAY, .key_size = sizeof(__u32), .value_size = sizeof(__u64), .max_entries = 1, }; struct bpf_map_def SEC("maps") pidmap = { .type = BPF_MAP_TYPE_ARRAY, .key_size = sizeof(__u32), .value_size = sizeof(__u32), .max_entries = 1, }; SEC("tracepoint/syscalls/sys_enter_nanosleep") int trace(void *ctx) { __u32 pid = bpf_get_current_pid_tgid(); __u32 key = 0, *expected_pid; __u64 *val; expected_pid = bpf_map_lookup_elem(&pidmap, &key); if (!expected_pid || *expected_pid != pid) return 0; val = bpf_map_lookup_elem(&cg_ids, &key); if (val) *val = bpf_get_current_cgroup_id(); return 0; } char _license[] SEC("license") = "GPL"; __u32 _version SEC("version") = 1; /* ignored by tracepoints, required by libbpf.a */