1 diff -Naur linux-2.6.26/include/linux/sysctl.h linux-2.6.26-dctcp-rev1.1.0/include/linux/sysctl.h
2 --- linux-2.6.26/include/linux/sysctl.h 2008-07-13 14:51:29.000000000 -0700
3 +++ linux-2.6.26-dctcp-rev1.1.0/include/linux/sysctl.h 2011-10-07 14:41:50.000000000 -0700
4 @@ -435,6 +435,9 @@
5 NET_TCP_ALLOWED_CONG_CONTROL=123,
6 NET_TCP_MAX_SSTHRESH=124,
7 NET_TCP_FRTO_RESPONSE=125,
8 + NET_TCP_DELAYED_ACK=126,
9 + NET_TCP_DCTCP_ENABLE=127,
10 + NET_TCP_DCTCP_SHIFT_G=128,
11 };
12
13 enum {
14 diff -Naur linux-2.6.26/include/linux/tcp.h linux-2.6.26-dctcp-rev1.1.0/include/linux/tcp.h
15 --- linux-2.6.26/include/linux/tcp.h 2008-07-13 14:51:29.000000000 -0700
16 +++ linux-2.6.26-dctcp-rev1.1.0/include/linux/tcp.h 2011-10-07 14:53:45.000000000 -0700
17 @@ -405,6 +405,15 @@
18 /* TCP MD5 Signagure Option information */
19 struct tcp_md5sig_info *md5sig_info;
20 #endif
21 +
22 +/* DCTCP Specific Parameters */
23 + u32 acked_bytes_ecn;
24 + u32 acked_bytes_total;
25 + u32 prior_rcv_nxt;
26 + u32 dctcp_alpha;
27 + u32 next_seq;
28 + u32 ce_state; /* 0: last pkt was non-ce , 1: last pkt was ce */
29 + u32 delayed_ack_reserved;
30 };
31
32 static inline struct tcp_sock *tcp_sk(const struct sock *sk)
33 diff -Naur linux-2.6.26/include/net/tcp.h linux-2.6.26-dctcp-rev1.1.0/include/net/tcp.h
34 --- linux-2.6.26/include/net/tcp.h 2008-07-13 14:51:29.000000000 -0700
35 +++ linux-2.6.26-dctcp-rev1.1.0/include/net/tcp.h 2011-10-07 14:41:50.000000000 -0700
36 @@ -214,6 +214,9 @@
37 extern int sysctl_tcp_fack;
38 extern int sysctl_tcp_reordering;
39 extern int sysctl_tcp_ecn;
40 +extern int sysctl_tcp_delayed_ack;
41 +extern int sysctl_tcp_dctcp_enable;
42 +extern int sysctl_tcp_dctcp_shift_g;
43 extern int sysctl_tcp_dsack;
44 extern int sysctl_tcp_mem[3];
45 extern int sysctl_tcp_wmem[3];
46 diff -Naur linux-2.6.26/kernel/sysctl_check.c linux-2.6.26-dctcp-rev1.1.0/kernel/sysctl_check.c
47 --- linux-2.6.26/kernel/sysctl_check.c 2008-07-13 14:51:29.000000000 -0700
48 +++ linux-2.6.26-dctcp-rev1.1.0/kernel/sysctl_check.c 2011-10-07 14:41:50.000000000 -0700
49 @@ -353,6 +353,9 @@
50 { NET_TCP_FACK, "tcp_fack" },
51 { NET_TCP_REORDERING, "tcp_reordering" },
52 { NET_TCP_ECN, "tcp_ecn" },
53 + { NET_TCP_DELAYED_ACK, "tcp_delayed_ack" },
54 + { NET_TCP_DCTCP_ENABLE, "tcp_dctcp_enable" },
55 + { NET_TCP_DCTCP_SHIFT_G, "tcp_dctcp_shift_g" },
56 { NET_TCP_DSACK, "tcp_dsack" },
57 { NET_TCP_MEM, "tcp_mem" },
58 { NET_TCP_WMEM, "tcp_wmem" },
59 diff -Naur linux-2.6.26/net/ipv4/sysctl_net_ipv4.c linux-2.6.26-dctcp-rev1.1.0/net/ipv4/sysctl_net_ipv4.c
60 --- linux-2.6.26/net/ipv4/sysctl_net_ipv4.c 2008-07-13 14:51:29.000000000 -0700
61 +++ linux-2.6.26-dctcp-rev1.1.0/net/ipv4/sysctl_net_ipv4.c 2011-10-07 14:41:50.000000000 -0700
62 @@ -506,6 +506,30 @@
63 .proc_handler = &proc_dointvec
64 },
65 {
66 + .ctl_name = NET_TCP_DELAYED_ACK,
67 + .procname = "tcp_delayed_ack",
68 + .data = &sysctl_tcp_delayed_ack,
69 + .maxlen = sizeof(int),
70 + .mode = 0644,
71 + .proc_handler = &proc_dointvec
72 + },
73 + {
74 + .ctl_name = NET_TCP_DCTCP_ENABLE,
75 + .procname = "tcp_dctcp_enable",
76 + .data = &sysctl_tcp_dctcp_enable,
77 + .maxlen = sizeof(int),
78 + .mode = 0644,
79 + .proc_handler = &proc_dointvec
80 + },
81 + {
82 + .ctl_name = NET_TCP_DCTCP_SHIFT_G,
83 + .procname = "tcp_dctcp_shift_g",
84 + .data = &sysctl_tcp_dctcp_shift_g,
85 + .maxlen = sizeof(int),
86 + .mode = 0644,
87 + .proc_handler = &proc_dointvec
88 + },
89 + {
90 .ctl_name = NET_TCP_DSACK,
91 .procname = "tcp_dsack",
92 .data = &sysctl_tcp_dsack,
93 diff -Naur linux-2.6.26/net/ipv4/tcp_input.c linux-2.6.26-dctcp-rev1.1.0/net/ipv4/tcp_input.c
94 --- linux-2.6.26/net/ipv4/tcp_input.c 2008-07-13 14:51:29.000000000 -0700
95 +++ linux-2.6.26-dctcp-rev1.1.0/net/ipv4/tcp_input.c 2011-10-07 14:53:21.000000000 -0700
96 @@ -79,6 +79,9 @@
97 int sysctl_tcp_fack __read_mostly = 1;
98 int sysctl_tcp_reordering __read_mostly = TCP_FASTRETRANS_THRESH;
99 int sysctl_tcp_ecn __read_mostly;
100 +int sysctl_tcp_delayed_ack __read_mostly = 1;
101 +int sysctl_tcp_dctcp_enable __read_mostly;
102 +int sysctl_tcp_dctcp_shift_g __read_mostly = 5; /* g=1/2^5 */
103 int sysctl_tcp_dsack __read_mostly = 1;
104 int sysctl_tcp_app_win __read_mostly = 31;
105 int sysctl_tcp_adv_win_scale __read_mostly = 2;
106 @@ -212,16 +215,68 @@
107 tp->ecn_flags &= ~TCP_ECN_DEMAND_CWR;
108 }
109
110 -static inline void TCP_ECN_check_ce(struct tcp_sock *tp, struct sk_buff *skb)
111 +static inline void TCP_ECN_dctcp_check_ce(struct sock *sk, struct tcp_sock *tp, struct sk_buff *skb)
112 {
113 if (tp->ecn_flags & TCP_ECN_OK) {
114 - if (INET_ECN_is_ce(TCP_SKB_CB(skb)->flags))
115 - tp->ecn_flags |= TCP_ECN_DEMAND_CWR;
116 - /* Funny extension: if ECT is not set on a segment,
117 - * it is surely retransmit. It is not in ECN RFC,
118 - * but Linux follows this rule. */
119 - else if (INET_ECN_is_not_ect((TCP_SKB_CB(skb)->flags)))
120 - tcp_enter_quickack_mode((struct sock *)tp);
121 + u32 temp_rcv_nxt;
122 +
123 + if (INET_ECN_is_ce(TCP_SKB_CB(skb)->flags)) {
124 +
125 + /* rcv_nxt is already update in previous process (tcp_rcv_established) */
126 +
127 + if(sysctl_tcp_dctcp_enable) {
128 +
129 + /* state has changed from CE=0 to CE=1 && delayed ack has not sent yet */
130 + if(tp->ce_state == 0 && tp->delayed_ack_reserved) {
131 +
132 + /* save current rcv_nxt */
133 + temp_rcv_nxt = tp->rcv_nxt;
134 + /* generate previous ack with CE=0 */
135 + tp->ecn_flags &= ~TCP_ECN_DEMAND_CWR;
136 + tp->rcv_nxt = tp->prior_rcv_nxt;
137 + tcp_send_ack(sk);
138 + /* recover current rcv_nxt */
139 + tp->rcv_nxt = temp_rcv_nxt;
140 + }
141 +
142 + tp->ce_state = 1;
143 + }
144 +
145 + tp->ecn_flags |= TCP_ECN_DEMAND_CWR;
146 +
147 +
148 + /* Funny extension: if ECT is not set on a segment,
149 + * it is surely retransmit. It is not in ECN RFC,
150 + * but Linux follows this rule. */
151 + } else if (INET_ECN_is_not_ect((TCP_SKB_CB(skb)->flags))) {
152 + tcp_enter_quickack_mode((struct sock *)tp);
153 + }else {
154 + /* It has ECT but it doesn‘t have CE */
155 +
156 + if(sysctl_tcp_dctcp_enable) {
157 +
158 + if(tp->ce_state != 0 && tp->delayed_ack_reserved) {
159 +
160 + /* save current rcv_nxt */
161 + temp_rcv_nxt = tp->rcv_nxt;
162 + /* generate previous ack with CE=1 */
163 + tp->ecn_flags |= TCP_ECN_DEMAND_CWR;
164 + tp->rcv_nxt = tp->prior_rcv_nxt;
165 + tcp_send_ack(sk);
166 + /* recover current rcv_nxt */
167 + tp->rcv_nxt = temp_rcv_nxt;
168 + }
169 +
170 + tp->ce_state = 0;
171 +
172 + /* deassert only when DCTCP is enabled */
173 + tp->ecn_flags &= ~TCP_ECN_DEMAND_CWR;
174 + }
175 +
176 + }
177 +
178 + /* set current rcv_nxt to prior_rcv_nxt */
179 + tp->prior_rcv_nxt = tp->rcv_nxt;
180 }
181 }
182
183 @@ -572,6 +627,8 @@
184 */
185 tcp_incr_quickack(sk);
186 icsk->icsk_ack.ato = TCP_ATO_MIN;
187 +
188 + tp->ce_state = 0;
189 } else {
190 int m = now - icsk->icsk_ack.lrcvtime;
191
192 @@ -592,7 +649,7 @@
193 }
194 icsk->icsk_ack.lrcvtime = now;
195
196 - TCP_ECN_check_ce(tp, skb);
197 + TCP_ECN_dctcp_check_ce(sk, tp, skb);
198
199 if (skb->len >= 128)
200 tcp_grow_window(sk, skb);
201 @@ -836,19 +893,54 @@
202 struct tcp_sock *tp = tcp_sk(sk);
203 const struct inet_connection_sock *icsk = inet_csk(sk);
204
205 + __u32 ssthresh_old;
206 + __u32 cwnd_old;
207 + __u32 cwnd_new;
208 +
209 tp->prior_ssthresh = 0;
210 tp->bytes_acked = 0;
211 if (icsk->icsk_ca_state < TCP_CA_CWR) {
212 tp->undo_marker = 0;
213 - if (set_ssthresh)
214 - tp->snd_ssthresh = icsk->icsk_ca_ops->ssthresh(sk);
215 - tp->snd_cwnd = min(tp->snd_cwnd,
216 - tcp_packets_in_flight(tp) + 1U);
217 +
218 + if(!sysctl_tcp_dctcp_enable) {
219 +
220 + if (set_ssthresh)
221 + tp->snd_ssthresh = icsk->icsk_ca_ops->ssthresh(sk);
222 +
223 + tp->snd_cwnd = min(tp->snd_cwnd,
224 + tcp_packets_in_flight(tp) + 1U);
225 +
226 + }else {
227 +
228 + cwnd_new = max (tp->snd_cwnd - ((tp->snd_cwnd * tp->dctcp_alpha)>>11) , 2U);
229 +
230 + if(set_ssthresh) {
231 +
232 + ssthresh_old = tp->snd_ssthresh;
233 + tp->snd_ssthresh = cwnd_new;
234 +
235 + /* printk("%llu alpha= %d ssth old= %d new= %d\n", */
236 + /* ktime_to_us(ktime_get_real()), */
237 + /* tp->dctcp_alpha, */
238 + /* ssthresh_old, */
239 + /* tp->snd_ssthresh); */
240 + }
241 +
242 + cwnd_old = tp->snd_cwnd;
243 + tp->snd_cwnd = cwnd_new;
244 +
245 + /* printk("%llu alpha= %d cwnd old= %d new= %d\n", */
246 + /* ktime_to_us(ktime_get_real()), */
247 + /* tp->dctcp_alpha, */
248 + /* cwnd_old, */
249 + /* tp->snd_cwnd); */
250 + }
251 +
252 tp->snd_cwnd_cnt = 0;
253 tp->high_seq = tp->snd_nxt;
254 tp->snd_cwnd_stamp = tcp_time_stamp;
255 TCP_ECN_queue_cwr(tp);
256 -
257 +
258 tcp_set_ca_state(sk, TCP_CA_CWR);
259 }
260 }
261 @@ -2513,7 +2605,8 @@
262 tcp_try_keep_open(sk);
263 tcp_moderate_cwnd(tp);
264 } else {
265 - tcp_cwnd_down(sk, flag);
266 + if(!sysctl_tcp_dctcp_enable)
267 + tcp_cwnd_down(sk, flag);
268 }
269 }
270
271 @@ -3216,6 +3309,9 @@
272 int prior_packets;
273 int frto_cwnd = 0;
274
275 + __u32 alpha_old;
276 + __u32 acked_bytes;
277 +
278 /* If the ack is newer than sent or older than previous acks
279 * then we can probably ignore it.
280 */
281 @@ -3269,6 +3365,45 @@
282 tcp_ca_event(sk, CA_EVENT_SLOW_ACK);
283 }
284
285 +
286 + /* START: DCTCP Processing */
287 +
288 + /* calc acked bytes */
289 + if(after(ack,prior_snd_una)) {
290 + acked_bytes = ack - prior_snd_una;
291 + } else {
292 + acked_bytes = inet_csk(sk)->icsk_ack.rcv_mss;
293 + }
294 +
295 + if(flag & FLAG_ECE)
296 + tp->acked_bytes_ecn += acked_bytes;
297 +
298 + tp->acked_bytes_total += acked_bytes;
299 +
300 + /* Expired RTT */
301 + if (!before(tp->snd_una,tp->next_seq)) {
302 +
303 + /* For avoiding denominator == 1 */
304 + if(tp->acked_bytes_total == 0) tp->acked_bytes_total = 1;
305 +
306 + alpha_old = tp->dctcp_alpha;
307 +
308 + /* alpha = (1-g) * alpha + g * F */
309 + tp->dctcp_alpha = alpha_old - (alpha_old >> sysctl_tcp_dctcp_shift_g)
310 + + (tp->acked_bytes_ecn << (10 - sysctl_tcp_dctcp_shift_g)) / tp->acked_bytes_total;
311 +
312 + if(tp->dctcp_alpha > 1024) tp->dctcp_alpha = 1024; /* round to 0-1024 */
313 +
314 + /* printk("bytes_ecn= %d total= %d alpha: old= %d new= %d\n", */
315 + /* tp->acked_bytes_ecn, tp->acked_bytes_total, alpha_old, tp->dctcp_alpha); */
316 +
317 + tp->acked_bytes_ecn = 0;
318 + tp->acked_bytes_total = 0;
319 + tp->next_seq = tp->snd_nxt;
320 + }
321 +
322 + /* END: DCTCP Processing */
323 +
324 /* We passed data and got it acked, remove any soft error
325 * log. Something worked...
326 */
327 @@ -4014,7 +4149,7 @@
328 goto queue_and_out;
329 }
330
331 - TCP_ECN_check_ce(tp, skb);
332 + TCP_ECN_dctcp_check_ce(sk, tp, skb);
333
334 if (tcp_try_rmem_schedule(sk, skb->truesize))
335 goto drop;
336 @@ -4421,6 +4556,8 @@
337 && __tcp_select_window(sk) >= tp->rcv_wnd) ||
338 /* We ACK each frame or... */
339 tcp_in_quickack_mode(sk) ||
340 + /* Delayed ACK is disabled or ... */
341 + sysctl_tcp_delayed_ack == 0 ||
342 /* We have out of order data. */
343 (ofo_possible && skb_peek(&tp->out_of_order_queue))) {
344 /* Then ack it now */
345 @@ -5419,6 +5556,9 @@
346 }
347
348 EXPORT_SYMBOL(sysctl_tcp_ecn);
349 +EXPORT_SYMBOL(sysctl_tcp_delayed_ack);
350 +EXPORT_SYMBOL(sysctl_tcp_dctcp_enable);
351 +EXPORT_SYMBOL(sysctl_tcp_dctcp_shift_g);
352 EXPORT_SYMBOL(sysctl_tcp_reordering);
353 EXPORT_SYMBOL(sysctl_tcp_adv_win_scale);
354 EXPORT_SYMBOL(tcp_parse_options);
355 diff -Naur linux-2.6.26/net/ipv4/tcp_minisocks.c linux-2.6.26-dctcp-rev1.1.0/net/ipv4/tcp_minisocks.c
356 --- linux-2.6.26/net/ipv4/tcp_minisocks.c 2008-07-13 14:51:29.000000000 -0700
357 +++ linux-2.6.26-dctcp-rev1.1.0/net/ipv4/tcp_minisocks.c 2011-10-07 15:03:45.000000000 -0700
358 @@ -398,6 +398,11 @@
359 newtp->rcv_wup = newtp->copied_seq = newtp->rcv_nxt = treq->rcv_isn + 1;
360 newtp->snd_sml = newtp->snd_una = newtp->snd_nxt = treq->snt_isn + 1;
361
362 + /* Initialize DCTCP internal parameters */
363 + newtp->next_seq = newtp->snd_nxt;
364 + newtp->acked_bytes_ecn = 0;
365 + newtp->acked_bytes_total = 0;
366 +
367 tcp_prequeue_init(newtp);
368
369 tcp_init_wl(newtp, treq->snt_isn, treq->rcv_isn);
370 diff -Naur linux-2.6.26/net/ipv4/tcp_output.c linux-2.6.26-dctcp-rev1.1.0/net/ipv4/tcp_output.c
371 --- linux-2.6.26/net/ipv4/tcp_output.c 2008-07-13 14:51:29.000000000 -0700
372 +++ linux-2.6.26-dctcp-rev1.1.0/net/ipv4/tcp_output.c 2011-10-07 14:41:50.000000000 -0700
373 @@ -290,7 +290,7 @@
374 struct tcp_sock *tp = tcp_sk(sk);
375
376 tp->ecn_flags = 0;
377 - if (sysctl_tcp_ecn) {
378 + if (sysctl_tcp_ecn || sysctl_tcp_dctcp_enable) {
379 TCP_SKB_CB(skb)->flags |= TCPCB_FLAG_ECE | TCPCB_FLAG_CWR;
380 tp->ecn_flags = TCP_ECN_OK;
381 }
382 @@ -600,6 +600,10 @@
383 TCP_ECN_send(sk, skb, tcp_header_size);
384 }
385
386 + /* In DCTCP, Assert ECT bit to all packets*/
387 + if(sysctl_tcp_dctcp_enable)
388 + INET_ECN_xmit(sk);
389 +
390 #ifdef CONFIG_TCP_MD5SIG
391 /* Calculate the MD5 hash, as we have all we need now */
392 if (md5) {
393 @@ -2352,6 +2356,11 @@
394 tcp_init_nondata_skb(buff, tp->write_seq++, TCPCB_FLAG_SYN);
395 TCP_ECN_send_syn(sk, buff);
396
397 + /* Initialize DCTCP internal parameters */
398 + tp->next_seq = tp->snd_nxt;
399 + tp->acked_bytes_ecn = 0;
400 + tp->acked_bytes_total = 0;
401 +
402 /* Send it off. */
403 TCP_SKB_CB(buff)->when = tcp_time_stamp;
404 tp->retrans_stamp = TCP_SKB_CB(buff)->when;
405 @@ -2385,6 +2394,10 @@
406 int ato = icsk->icsk_ack.ato;
407 unsigned long timeout;
408
409 + /* Delayed ACK reserved flag for DCTCP */
410 + struct tcp_sock *tp = tcp_sk(sk);
411 + tp->delayed_ack_reserved = 1;
412 +
413 if (ato > TCP_DELACK_MIN) {
414 const struct tcp_sock *tp = tcp_sk(sk);
415 int max_ato = HZ / 2;
416 @@ -2436,6 +2449,10 @@
417 {
418 struct sk_buff *buff;
419
420 + /* Delayed ACK reserved flag for DCTCP */
421 + struct tcp_sock *tp = tcp_sk(sk);
422 + tp->delayed_ack_reserved = 0;
423 +
424 /* If we have been reset, we may not send again. */
425 if (sk->sk_state == TCP_CLOSE)
426 return;
https://github.com/myasuda/DCTCP-Linux/blob/master/dctcp-2.6.26-rev1.1.0.patch
时间： 2024-10-19 04:21:21