// SPDX-License-Identifier: GPL-2.0
|
// Copyright (c) 2018 Facebook
|
|
#include <linux/bpf.h>
|
#include <linux/pkt_cls.h>
|
|
#include <string.h>
|
|
#include <bpf/bpf_helpers.h>
|
|
#define NUM_CGROUP_LEVELS 4
|
|
struct bpf_map_def SEC("maps") cgroup_ids = {
|
.type = BPF_MAP_TYPE_ARRAY,
|
.key_size = sizeof(__u32),
|
.value_size = sizeof(__u64),
|
.max_entries = NUM_CGROUP_LEVELS,
|
};
|
|
static __always_inline void log_nth_level(struct __sk_buff *skb, __u32 level)
|
{
|
__u64 id;
|
|
/* [1] &level passed to external function that may change it, it's
|
* incompatible with loop unroll.
|
*/
|
id = bpf_skb_ancestor_cgroup_id(skb, level);
|
bpf_map_update_elem(&cgroup_ids, &level, &id, 0);
|
}
|
|
SEC("cgroup_id_logger")
|
int log_cgroup_id(struct __sk_buff *skb)
|
{
|
/* Loop unroll can't be used here due to [1]. Unrolling manually.
|
* Number of calls should be in sync with NUM_CGROUP_LEVELS.
|
*/
|
log_nth_level(skb, 0);
|
log_nth_level(skb, 1);
|
log_nth_level(skb, 2);
|
log_nth_level(skb, 3);
|
|
return TC_ACT_OK;
|
}
|
|
int _version SEC("version") = 1;
|
|
char _license[] SEC("license") = "GPL";
|
