1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
|
/* SPDX-License-Identifier: GPL-2.0
*
* Copyright (c) 2019 Facebook
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of version 2 of the GNU General Public
* License as published by the Free Software Foundation.
*
* Include file for sample Host Bandwidth Manager (HBM) BPF programs
*/
#define KBUILD_MODNAME "foo"
#include <uapi/linux/bpf.h>
#include <uapi/linux/if_ether.h>
#include <uapi/linux/if_packet.h>
#include <uapi/linux/ip.h>
#include <uapi/linux/ipv6.h>
#include <uapi/linux/in.h>
#include <uapi/linux/tcp.h>
#include <uapi/linux/filter.h>
#include <uapi/linux/pkt_cls.h>
#include <net/ipv6.h>
#include <net/inet_ecn.h>
#include <bpf/bpf_endian.h>
#include <bpf/bpf_helpers.h>
#include "hbm.h"
#define DROP_PKT 0
#define ALLOW_PKT 1
#define TCP_ECN_OK 1
#define CWR 2
#ifndef HBM_DEBUG // Define HBM_DEBUG to enable debugging
#undef bpf_printk
#define bpf_printk(fmt, ...)
#endif
#define INITIAL_CREDIT_PACKETS 100
#define MAX_BYTES_PER_PACKET 1500
#define MARK_THRESH (40 * MAX_BYTES_PER_PACKET)
#define DROP_THRESH (80 * 5 * MAX_BYTES_PER_PACKET)
#define LARGE_PKT_DROP_THRESH (DROP_THRESH - (15 * MAX_BYTES_PER_PACKET))
#define MARK_REGION_SIZE (LARGE_PKT_DROP_THRESH - MARK_THRESH)
#define LARGE_PKT_THRESH 120
#define MAX_CREDIT (100 * MAX_BYTES_PER_PACKET)
#define INIT_CREDIT (INITIAL_CREDIT_PACKETS * MAX_BYTES_PER_PACKET)
// Time base accounting for fq's EDT
#define BURST_SIZE_NS 100000 // 100us
#define MARK_THRESH_NS 50000 // 50us
#define DROP_THRESH_NS 500000 // 500us
// Reserve 20us of queuing for small packets (less than 120 bytes)
#define LARGE_PKT_DROP_THRESH_NS (DROP_THRESH_NS - 20000)
#define MARK_REGION_SIZE_NS (LARGE_PKT_DROP_THRESH_NS - MARK_THRESH_NS)
// rate in bytes per ns << 20
#define CREDIT_PER_NS(delta, rate) ((((u64)(delta)) * (rate)) >> 20)
#define BYTES_PER_NS(delta, rate) ((((u64)(delta)) * (rate)) >> 20)
#define BYTES_TO_NS(bytes, rate) div64_u64(((u64)(bytes)) << 20, (u64)(rate))
struct {
__uint(type, BPF_MAP_TYPE_CGROUP_STORAGE);
__type(key, struct bpf_cgroup_storage_key);
__type(value, struct hbm_vqueue);
} queue_state SEC(".maps");
struct {
__uint(type, BPF_MAP_TYPE_ARRAY);
__uint(max_entries, 1);
__type(key, u32);
__type(value, struct hbm_queue_stats);
} queue_stats SEC(".maps");
struct hbm_pkt_info {
int cwnd;
int rtt;
int packets_out;
bool is_ip;
bool is_tcp;
short ecn;
};
static int get_tcp_info(struct __sk_buff *skb, struct hbm_pkt_info *pkti)
{
struct bpf_sock *sk;
struct bpf_tcp_sock *tp;
sk = skb->sk;
if (sk) {
sk = bpf_sk_fullsock(sk);
if (sk) {
if (sk->protocol == IPPROTO_TCP) {
tp = bpf_tcp_sock(sk);
if (tp) {
pkti->cwnd = tp->snd_cwnd;
pkti->rtt = tp->srtt_us >> 3;
pkti->packets_out = tp->packets_out;
return 0;
}
}
}
}
pkti->cwnd = 0;
pkti->rtt = 0;
pkti->packets_out = 0;
return 1;
}
static void hbm_get_pkt_info(struct __sk_buff *skb,
struct hbm_pkt_info *pkti)
{
struct iphdr iph;
struct ipv6hdr *ip6h;
pkti->cwnd = 0;
pkti->rtt = 0;
bpf_skb_load_bytes(skb, 0, &iph, 12);
if (iph.version == 6) {
ip6h = (struct ipv6hdr *)&iph;
pkti->is_ip = true;
pkti->is_tcp = (ip6h->nexthdr == 6);
pkti->ecn = (ip6h->flow_lbl[0] >> 4) & INET_ECN_MASK;
} else if (iph.version == 4) {
pkti->is_ip = true;
pkti->is_tcp = (iph.protocol == 6);
pkti->ecn = iph.tos & INET_ECN_MASK;
} else {
pkti->is_ip = false;
pkti->is_tcp = false;
pkti->ecn = 0;
}
if (pkti->is_tcp)
get_tcp_info(skb, pkti);
}
static __always_inline void hbm_init_vqueue(struct hbm_vqueue *qdp, int rate)
{
bpf_printk("Initializing queue_state, rate:%d\n", rate * 128);
qdp->lasttime = bpf_ktime_get_ns();
qdp->credit = INIT_CREDIT;
qdp->rate = rate * 128;
}
static __always_inline void hbm_init_edt_vqueue(struct hbm_vqueue *qdp,
int rate)
{
unsigned long long curtime;
curtime = bpf_ktime_get_ns();
bpf_printk("Initializing queue_state, rate:%d\n", rate * 128);
qdp->lasttime = curtime - BURST_SIZE_NS; // support initial burst
qdp->credit = 0; // not used
qdp->rate = rate * 128;
}
static __always_inline void hbm_update_stats(struct hbm_queue_stats *qsp,
int len,
unsigned long long curtime,
bool congestion_flag,
bool drop_flag,
bool cwr_flag,
bool ecn_ce_flag,
struct hbm_pkt_info *pkti,
int credit)
{
int rv = ALLOW_PKT;
if (qsp != NULL) {
// Following is needed for work conserving
__sync_add_and_fetch(&(qsp->bytes_total), len);
if (qsp->stats) {
// Optionally update statistics
if (qsp->firstPacketTime == 0)
qsp->firstPacketTime = curtime;
qsp->lastPacketTime = curtime;
__sync_add_and_fetch(&(qsp->pkts_total), 1);
if (congestion_flag) {
__sync_add_and_fetch(&(qsp->pkts_marked), 1);
__sync_add_and_fetch(&(qsp->bytes_marked), len);
}
if (drop_flag) {
__sync_add_and_fetch(&(qsp->pkts_dropped), 1);
__sync_add_and_fetch(&(qsp->bytes_dropped),
len);
}
if (ecn_ce_flag)
__sync_add_and_fetch(&(qsp->pkts_ecn_ce), 1);
if (pkti->cwnd) {
__sync_add_and_fetch(&(qsp->sum_cwnd),
pkti->cwnd);
__sync_add_and_fetch(&(qsp->sum_cwnd_cnt), 1);
}
if (pkti->rtt)
__sync_add_and_fetch(&(qsp->sum_rtt),
pkti->rtt);
__sync_add_and_fetch(&(qsp->sum_credit), credit);
if (drop_flag)
rv = DROP_PKT;
if (cwr_flag)
rv |= 2;
if (rv == DROP_PKT)
__sync_add_and_fetch(&(qsp->returnValCount[0]),
1);
else if (rv == ALLOW_PKT)
__sync_add_and_fetch(&(qsp->returnValCount[1]),
1);
else if (rv == 2)
__sync_add_and_fetch(&(qsp->returnValCount[2]),
1);
else if (rv == 3)
__sync_add_and_fetch(&(qsp->returnValCount[3]),
1);
}
}
}
|
