linux/tools/testing/selftests/bpf/progs/get_cgroup_id_kern.c

41 lines
918 B
C

// 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 */