// SPDX-License-Identifier: GPL-2.0 #include <linux/bpf.h> #include <linux/version.h> #include <bpf/bpf_helpers.h> #include "netcnt_common.h" #define MAX_BPS (3 * 1024 * 1024) #define REFRESH_TIME_NS 100000000 #define NS_PER_SEC 1000000000 struct { __uint(type, BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE); __type(key, struct bpf_cgroup_storage_key); __type(value, struct percpu_net_cnt); } percpu_netcnt SEC(".maps"); struct { __uint(type, BPF_MAP_TYPE_CGROUP_STORAGE); __type(key, struct bpf_cgroup_storage_key); __type(value, struct net_cnt); } netcnt SEC(".maps"); 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;