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1// SPDX-License-Identifier: GPL-2.02#include <linux/bpf.h>3#include <linux/version.h>4 5#include <bpf/bpf_helpers.h>6#include "netcnt_common.h"7 8#define MAX_BPS (3 * 1024 * 1024)9 10#define REFRESH_TIME_NS 10000000011#define NS_PER_SEC 100000000012 13struct {14 __uint(type, BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE);15 __type(key, struct bpf_cgroup_storage_key);16 __type(value, union percpu_net_cnt);17} percpu_netcnt SEC(".maps");18 19struct {20 __uint(type, BPF_MAP_TYPE_CGROUP_STORAGE);21 __type(key, struct bpf_cgroup_storage_key);22 __type(value, union net_cnt);23} netcnt SEC(".maps");24 25SEC("cgroup/skb")26int bpf_nextcnt(struct __sk_buff *skb)27{28 union percpu_net_cnt *percpu_cnt;29 union net_cnt *cnt;30 __u64 ts, dt;31 int ret;32 33 cnt = bpf_get_local_storage(&netcnt, 0);34 percpu_cnt = bpf_get_local_storage(&percpu_netcnt, 0);35 36 percpu_cnt->packets++;37 percpu_cnt->bytes += skb->len;38 39 if (percpu_cnt->packets > MAX_PERCPU_PACKETS) {40 __sync_fetch_and_add(&cnt->packets,41 percpu_cnt->packets);42 percpu_cnt->packets = 0;43 44 __sync_fetch_and_add(&cnt->bytes,45 percpu_cnt->bytes);46 percpu_cnt->bytes = 0;47 }48 49 ts = bpf_ktime_get_ns();50 dt = ts - percpu_cnt->prev_ts;51 52 dt *= MAX_BPS;53 dt /= NS_PER_SEC;54 55 if (cnt->bytes + percpu_cnt->bytes - percpu_cnt->prev_bytes < dt)56 ret = 1;57 else58 ret = 0;59 60 if (dt > REFRESH_TIME_NS) {61 percpu_cnt->prev_ts = ts;62 percpu_cnt->prev_packets = cnt->packets;63 percpu_cnt->prev_bytes = cnt->bytes;64 }65 66 return !!ret;67}68 69char _license[] SEC("license") = "GPL";70