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// SPDX-License-Identifier: GPL-2.0
#include <linux/bpf.h>
#include <linux/version.h>
#include "bpf_helpers.h"
#include "netcnt_common.h"
#define MAX_BPS (3 * 1024 * 1024)
#define REFRESH_TIME_NS 100000000
#define NS_PER_SEC 1000000000
struct bpf_map_def SEC("maps") percpu_netcnt = {
.type = BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE,
.key_size = sizeof(struct bpf_cgroup_storage_key),
.value_size = sizeof(struct percpu_net_cnt),
};
BPF_ANNOTATE_KV_PAIR(percpu_netcnt, struct bpf_cgroup_storage_key,
struct percpu_net_cnt);
struct bpf_map_def SEC("maps") netcnt = {
.type = BPF_MAP_TYPE_CGROUP_STORAGE,
.key_size = sizeof(struct bpf_cgroup_storage_key),
.value_size = sizeof(struct net_cnt),
};
BPF_ANNOTATE_KV_PAIR(netcnt, struct bpf_cgroup_storage_key,
struct net_cnt);
SEC("cgroup/skb")
int bpf_nextcnt(struct __sk_buff *skb)
{
struct percpu_net_cnt *percpu_cnt;
char fmt[] = "%d %llu %llu\n";
struct net_cnt *cnt;
__u64 ts, dt;
int ret;
cnt = bpf_get_local_storage(&netcnt, 0);
percpu_cnt = bpf_get_local_storage(&percpu_netcnt, 0);
percpu_cnt->packets++;
percpu_cnt->bytes += skb->len;
if (percpu_cnt->packets > MAX_PERCPU_PACKETS) {
__sync_fetch_and_add(&cnt->packets,
percpu_cnt->packets);
percpu_cnt->packets = 0;
__sync_fetch_and_add(&cnt->bytes,
percpu_cnt->bytes);
percpu_cnt->bytes = 0;
}
ts = bpf_ktime_get_ns();
dt = ts - percpu_cnt->prev_ts;
dt *= MAX_BPS;
dt /= NS_PER_SEC;
if (cnt->bytes + percpu_cnt->bytes - percpu_cnt->prev_bytes < dt)
ret = 1;
else
ret = 0;
if (dt > REFRESH_TIME_NS) {
percpu_cnt->prev_ts = ts;
percpu_cnt->prev_packets = cnt->packets;
percpu_cnt->prev_bytes = cnt->bytes;
}
return !!ret;
}
char _license[] SEC("license") = "GPL";
__u32 _version SEC("version") = LINUX_VERSION_CODE;
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