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11#define KBUILD_MODNAME "foo"
12#include <stddef.h>
13#include <stdbool.h>
14#include <uapi/linux/bpf.h>
15#include <uapi/linux/if_ether.h>
16#include <uapi/linux/if_packet.h>
17#include <uapi/linux/ip.h>
18#include <uapi/linux/ipv6.h>
19#include <uapi/linux/in.h>
20#include <uapi/linux/tcp.h>
21#include <uapi/linux/filter.h>
22#include <uapi/linux/pkt_cls.h>
23#include <net/ipv6.h>
24#include <net/inet_ecn.h>
25#include <bpf/bpf_endian.h>
26#include <bpf/bpf_helpers.h>
27#include "hbm.h"
28
29#define DROP_PKT 0
30#define ALLOW_PKT 1
31#define TCP_ECN_OK 1
32#define CWR 2
33
34#ifndef HBM_DEBUG
35#undef bpf_printk
36#define bpf_printk(fmt, ...)
37#endif
38
39#define INITIAL_CREDIT_PACKETS 100
40#define MAX_BYTES_PER_PACKET 1500
41#define MARK_THRESH (40 * MAX_BYTES_PER_PACKET)
42#define DROP_THRESH (80 * 5 * MAX_BYTES_PER_PACKET)
43#define LARGE_PKT_DROP_THRESH (DROP_THRESH - (15 * MAX_BYTES_PER_PACKET))
44#define MARK_REGION_SIZE (LARGE_PKT_DROP_THRESH - MARK_THRESH)
45#define LARGE_PKT_THRESH 120
46#define MAX_CREDIT (100 * MAX_BYTES_PER_PACKET)
47#define INIT_CREDIT (INITIAL_CREDIT_PACKETS * MAX_BYTES_PER_PACKET)
48
49
50#define BURST_SIZE_NS 100000
51#define MARK_THRESH_NS 50000
52#define DROP_THRESH_NS 500000
53
54#define LARGE_PKT_DROP_THRESH_NS (DROP_THRESH_NS - 20000)
55#define MARK_REGION_SIZE_NS (LARGE_PKT_DROP_THRESH_NS - MARK_THRESH_NS)
56
57
58#define CREDIT_PER_NS(delta, rate) ((((u64)(delta)) * (rate)) >> 20)
59#define BYTES_PER_NS(delta, rate) ((((u64)(delta)) * (rate)) >> 20)
60#define BYTES_TO_NS(bytes, rate) div64_u64(((u64)(bytes)) << 20, (u64)(rate))
61
62struct {
63 __uint(type, BPF_MAP_TYPE_CGROUP_STORAGE);
64 __type(key, struct bpf_cgroup_storage_key);
65 __type(value, struct hbm_vqueue);
66} queue_state SEC(".maps");
67
68struct {
69 __uint(type, BPF_MAP_TYPE_ARRAY);
70 __uint(max_entries, 1);
71 __type(key, u32);
72 __type(value, struct hbm_queue_stats);
73} queue_stats SEC(".maps");
74
75struct hbm_pkt_info {
76 int cwnd;
77 int rtt;
78 int packets_out;
79 bool is_ip;
80 bool is_tcp;
81 short ecn;
82};
83
84static int get_tcp_info(struct __sk_buff *skb, struct hbm_pkt_info *pkti)
85{
86 struct bpf_sock *sk;
87 struct bpf_tcp_sock *tp;
88
89 sk = skb->sk;
90 if (sk) {
91 sk = bpf_sk_fullsock(sk);
92 if (sk) {
93 if (sk->protocol == IPPROTO_TCP) {
94 tp = bpf_tcp_sock(sk);
95 if (tp) {
96 pkti->cwnd = tp->snd_cwnd;
97 pkti->rtt = tp->srtt_us >> 3;
98 pkti->packets_out = tp->packets_out;
99 return 0;
100 }
101 }
102 }
103 }
104 pkti->cwnd = 0;
105 pkti->rtt = 0;
106 pkti->packets_out = 0;
107 return 1;
108}
109
110static void hbm_get_pkt_info(struct __sk_buff *skb,
111 struct hbm_pkt_info *pkti)
112{
113 struct iphdr iph;
114 struct ipv6hdr *ip6h;
115
116 pkti->cwnd = 0;
117 pkti->rtt = 0;
118 bpf_skb_load_bytes(skb, 0, &iph, 12);
119 if (iph.version == 6) {
120 ip6h = (struct ipv6hdr *)&iph;
121 pkti->is_ip = true;
122 pkti->is_tcp = (ip6h->nexthdr == 6);
123 pkti->ecn = (ip6h->flow_lbl[0] >> 4) & INET_ECN_MASK;
124 } else if (iph.version == 4) {
125 pkti->is_ip = true;
126 pkti->is_tcp = (iph.protocol == 6);
127 pkti->ecn = iph.tos & INET_ECN_MASK;
128 } else {
129 pkti->is_ip = false;
130 pkti->is_tcp = false;
131 pkti->ecn = 0;
132 }
133 if (pkti->is_tcp)
134 get_tcp_info(skb, pkti);
135}
136
137static __always_inline void hbm_init_vqueue(struct hbm_vqueue *qdp, int rate)
138{
139 bpf_printk("Initializing queue_state, rate:%d\n", rate * 128);
140 qdp->lasttime = bpf_ktime_get_ns();
141 qdp->credit = INIT_CREDIT;
142 qdp->rate = rate * 128;
143}
144
145static __always_inline void hbm_init_edt_vqueue(struct hbm_vqueue *qdp,
146 int rate)
147{
148 unsigned long long curtime;
149
150 curtime = bpf_ktime_get_ns();
151 bpf_printk("Initializing queue_state, rate:%d\n", rate * 128);
152 qdp->lasttime = curtime - BURST_SIZE_NS;
153 qdp->credit = 0;
154 qdp->rate = rate * 128;
155}
156
157static __always_inline void hbm_update_stats(struct hbm_queue_stats *qsp,
158 int len,
159 unsigned long long curtime,
160 bool congestion_flag,
161 bool drop_flag,
162 bool cwr_flag,
163 bool ecn_ce_flag,
164 struct hbm_pkt_info *pkti,
165 int credit)
166{
167 int rv = ALLOW_PKT;
168
169 if (qsp != NULL) {
170
171 __sync_add_and_fetch(&(qsp->bytes_total), len);
172 if (qsp->stats) {
173
174 if (qsp->firstPacketTime == 0)
175 qsp->firstPacketTime = curtime;
176 qsp->lastPacketTime = curtime;
177 __sync_add_and_fetch(&(qsp->pkts_total), 1);
178 if (congestion_flag) {
179 __sync_add_and_fetch(&(qsp->pkts_marked), 1);
180 __sync_add_and_fetch(&(qsp->bytes_marked), len);
181 }
182 if (drop_flag) {
183 __sync_add_and_fetch(&(qsp->pkts_dropped), 1);
184 __sync_add_and_fetch(&(qsp->bytes_dropped),
185 len);
186 }
187 if (ecn_ce_flag)
188 __sync_add_and_fetch(&(qsp->pkts_ecn_ce), 1);
189 if (pkti->cwnd) {
190 __sync_add_and_fetch(&(qsp->sum_cwnd),
191 pkti->cwnd);
192 __sync_add_and_fetch(&(qsp->sum_cwnd_cnt), 1);
193 }
194 if (pkti->rtt)
195 __sync_add_and_fetch(&(qsp->sum_rtt),
196 pkti->rtt);
197 __sync_add_and_fetch(&(qsp->sum_credit), credit);
198
199 if (drop_flag)
200 rv = DROP_PKT;
201 if (cwr_flag)
202 rv |= 2;
203 if (rv == DROP_PKT)
204 __sync_add_and_fetch(&(qsp->returnValCount[0]),
205 1);
206 else if (rv == ALLOW_PKT)
207 __sync_add_and_fetch(&(qsp->returnValCount[1]),
208 1);
209 else if (rv == 2)
210 __sync_add_and_fetch(&(qsp->returnValCount[2]),
211 1);
212 else if (rv == 3)
213 __sync_add_and_fetch(&(qsp->returnValCount[3]),
214 1);
215 }
216 }
217}
218
