Commit | Line | Data |
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25db26a9 VCG |
1 | // SPDX-License-Identifier: GPL-2.0 |
2 | ||
3 | /* net/sched/sch_etf.c Earliest TxTime First queueing discipline. | |
4 | * | |
5 | * Authors: Jesus Sanchez-Palencia <jesus.sanchez-palencia@intel.com> | |
6 | * Vinicius Costa Gomes <vinicius.gomes@intel.com> | |
7 | */ | |
8 | ||
9 | #include <linux/module.h> | |
10 | #include <linux/types.h> | |
11 | #include <linux/kernel.h> | |
12 | #include <linux/string.h> | |
13 | #include <linux/errno.h> | |
4b15c707 | 14 | #include <linux/errqueue.h> |
25db26a9 VCG |
15 | #include <linux/rbtree.h> |
16 | #include <linux/skbuff.h> | |
17 | #include <linux/posix-timers.h> | |
18 | #include <net/netlink.h> | |
19 | #include <net/sch_generic.h> | |
20 | #include <net/pkt_sched.h> | |
21 | #include <net/sock.h> | |
22 | ||
23 | #define DEADLINE_MODE_IS_ON(x) ((x)->flags & TC_ETF_DEADLINE_MODE_ON) | |
88cab771 | 24 | #define OFFLOAD_IS_ON(x) ((x)->flags & TC_ETF_OFFLOAD_ON) |
d14d2b20 | 25 | #define SKIP_SOCK_CHECK_IS_SET(x) ((x)->flags & TC_ETF_SKIP_SOCK_CHECK) |
25db26a9 VCG |
26 | |
27 | struct etf_sched_data { | |
88cab771 | 28 | bool offload; |
25db26a9 | 29 | bool deadline_mode; |
d14d2b20 | 30 | bool skip_sock_check; |
25db26a9 VCG |
31 | int clockid; |
32 | int queue; | |
33 | s32 delta; /* in ns */ | |
34 | ktime_t last; /* The txtime of the last skb sent to the netdevice. */ | |
09fd4860 | 35 | struct rb_root_cached head; |
25db26a9 VCG |
36 | struct qdisc_watchdog watchdog; |
37 | ktime_t (*get_time)(void); | |
38 | }; | |
39 | ||
40 | static const struct nla_policy etf_policy[TCA_ETF_MAX + 1] = { | |
41 | [TCA_ETF_PARMS] = { .len = sizeof(struct tc_etf_qopt) }, | |
42 | }; | |
43 | ||
44 | static inline int validate_input_params(struct tc_etf_qopt *qopt, | |
45 | struct netlink_ext_ack *extack) | |
46 | { | |
47 | /* Check if params comply to the following rules: | |
48 | * * Clockid and delta must be valid. | |
49 | * | |
50 | * * Dynamic clockids are not supported. | |
51 | * | |
52 | * * Delta must be a positive integer. | |
88cab771 JSP |
53 | * |
54 | * Also note that for the HW offload case, we must | |
55 | * expect that system clocks have been synchronized to PHC. | |
25db26a9 VCG |
56 | */ |
57 | if (qopt->clockid < 0) { | |
58 | NL_SET_ERR_MSG(extack, "Dynamic clockids are not supported"); | |
59 | return -ENOTSUPP; | |
60 | } | |
61 | ||
62 | if (qopt->clockid != CLOCK_TAI) { | |
63 | NL_SET_ERR_MSG(extack, "Invalid clockid. CLOCK_TAI must be used"); | |
64 | return -EINVAL; | |
65 | } | |
66 | ||
67 | if (qopt->delta < 0) { | |
68 | NL_SET_ERR_MSG(extack, "Delta must be positive"); | |
69 | return -EINVAL; | |
70 | } | |
71 | ||
72 | return 0; | |
73 | } | |
74 | ||
75 | static bool is_packet_valid(struct Qdisc *sch, struct sk_buff *nskb) | |
76 | { | |
77 | struct etf_sched_data *q = qdisc_priv(sch); | |
78 | ktime_t txtime = nskb->tstamp; | |
79 | struct sock *sk = nskb->sk; | |
80 | ktime_t now; | |
81 | ||
d14d2b20 VP |
82 | if (q->skip_sock_check) |
83 | goto skip; | |
84 | ||
a1211bf9 | 85 | if (!sk || !sk_fullsock(sk)) |
25db26a9 VCG |
86 | return false; |
87 | ||
88 | if (!sock_flag(sk, SOCK_TXTIME)) | |
89 | return false; | |
90 | ||
91 | /* We don't perform crosstimestamping. | |
92 | * Drop if packet's clockid differs from qdisc's. | |
93 | */ | |
94 | if (sk->sk_clockid != q->clockid) | |
95 | return false; | |
96 | ||
97 | if (sk->sk_txtime_deadline_mode != q->deadline_mode) | |
98 | return false; | |
99 | ||
d14d2b20 | 100 | skip: |
25db26a9 VCG |
101 | now = q->get_time(); |
102 | if (ktime_before(txtime, now) || ktime_before(txtime, q->last)) | |
103 | return false; | |
104 | ||
105 | return true; | |
106 | } | |
107 | ||
108 | static struct sk_buff *etf_peek_timesortedlist(struct Qdisc *sch) | |
109 | { | |
110 | struct etf_sched_data *q = qdisc_priv(sch); | |
111 | struct rb_node *p; | |
112 | ||
09fd4860 | 113 | p = rb_first_cached(&q->head); |
25db26a9 VCG |
114 | if (!p) |
115 | return NULL; | |
116 | ||
117 | return rb_to_skb(p); | |
118 | } | |
119 | ||
120 | static void reset_watchdog(struct Qdisc *sch) | |
121 | { | |
122 | struct etf_sched_data *q = qdisc_priv(sch); | |
123 | struct sk_buff *skb = etf_peek_timesortedlist(sch); | |
124 | ktime_t next; | |
125 | ||
3fcbdaee JSP |
126 | if (!skb) { |
127 | qdisc_watchdog_cancel(&q->watchdog); | |
25db26a9 | 128 | return; |
3fcbdaee | 129 | } |
25db26a9 VCG |
130 | |
131 | next = ktime_sub_ns(skb->tstamp, q->delta); | |
132 | qdisc_watchdog_schedule_ns(&q->watchdog, ktime_to_ns(next)); | |
133 | } | |
134 | ||
4b15c707 JSP |
135 | static void report_sock_error(struct sk_buff *skb, u32 err, u8 code) |
136 | { | |
137 | struct sock_exterr_skb *serr; | |
138 | struct sk_buff *clone; | |
139 | ktime_t txtime = skb->tstamp; | |
a1211bf9 | 140 | struct sock *sk = skb->sk; |
4b15c707 | 141 | |
a1211bf9 | 142 | if (!sk || !sk_fullsock(sk) || !(sk->sk_txtime_report_errors)) |
4b15c707 JSP |
143 | return; |
144 | ||
145 | clone = skb_clone(skb, GFP_ATOMIC); | |
146 | if (!clone) | |
147 | return; | |
148 | ||
149 | serr = SKB_EXT_ERR(clone); | |
150 | serr->ee.ee_errno = err; | |
151 | serr->ee.ee_origin = SO_EE_ORIGIN_TXTIME; | |
152 | serr->ee.ee_type = 0; | |
153 | serr->ee.ee_code = code; | |
154 | serr->ee.ee_pad = 0; | |
155 | serr->ee.ee_data = (txtime >> 32); /* high part of tstamp */ | |
156 | serr->ee.ee_info = txtime; /* low part of tstamp */ | |
157 | ||
a1211bf9 | 158 | if (sock_queue_err_skb(sk, clone)) |
4b15c707 JSP |
159 | kfree_skb(clone); |
160 | } | |
161 | ||
25db26a9 VCG |
162 | static int etf_enqueue_timesortedlist(struct sk_buff *nskb, struct Qdisc *sch, |
163 | struct sk_buff **to_free) | |
164 | { | |
165 | struct etf_sched_data *q = qdisc_priv(sch); | |
09fd4860 | 166 | struct rb_node **p = &q->head.rb_root.rb_node, *parent = NULL; |
25db26a9 | 167 | ktime_t txtime = nskb->tstamp; |
09fd4860 | 168 | bool leftmost = true; |
25db26a9 | 169 | |
4b15c707 JSP |
170 | if (!is_packet_valid(sch, nskb)) { |
171 | report_sock_error(nskb, EINVAL, | |
172 | SO_EE_CODE_TXTIME_INVALID_PARAM); | |
25db26a9 | 173 | return qdisc_drop(nskb, sch, to_free); |
4b15c707 | 174 | } |
25db26a9 VCG |
175 | |
176 | while (*p) { | |
177 | struct sk_buff *skb; | |
178 | ||
179 | parent = *p; | |
180 | skb = rb_to_skb(parent); | |
28aa7c86 | 181 | if (ktime_compare(txtime, skb->tstamp) >= 0) { |
25db26a9 | 182 | p = &parent->rb_right; |
09fd4860 JSP |
183 | leftmost = false; |
184 | } else { | |
25db26a9 | 185 | p = &parent->rb_left; |
09fd4860 | 186 | } |
25db26a9 VCG |
187 | } |
188 | rb_link_node(&nskb->rbnode, parent, p); | |
09fd4860 | 189 | rb_insert_color_cached(&nskb->rbnode, &q->head, leftmost); |
25db26a9 VCG |
190 | |
191 | qdisc_qstats_backlog_inc(sch, nskb); | |
192 | sch->q.qlen++; | |
193 | ||
194 | /* Now we may need to re-arm the qdisc watchdog for the next packet. */ | |
195 | reset_watchdog(sch); | |
196 | ||
197 | return NET_XMIT_SUCCESS; | |
198 | } | |
199 | ||
37342bda JSP |
200 | static void timesortedlist_drop(struct Qdisc *sch, struct sk_buff *skb, |
201 | ktime_t now) | |
25db26a9 VCG |
202 | { |
203 | struct etf_sched_data *q = qdisc_priv(sch); | |
cbeeb8ef | 204 | struct sk_buff *to_free = NULL; |
37342bda | 205 | struct sk_buff *tmp = NULL; |
25db26a9 | 206 | |
37342bda JSP |
207 | skb_rbtree_walk_from_safe(skb, tmp) { |
208 | if (ktime_after(skb->tstamp, now)) | |
209 | break; | |
25db26a9 | 210 | |
37342bda | 211 | rb_erase_cached(&skb->rbnode, &q->head); |
25db26a9 | 212 | |
37342bda JSP |
213 | /* The rbnode field in the skb re-uses these fields, now that |
214 | * we are done with the rbnode, reset them. | |
215 | */ | |
216 | skb->next = NULL; | |
217 | skb->prev = NULL; | |
218 | skb->dev = qdisc_dev(sch); | |
25db26a9 | 219 | |
37342bda | 220 | report_sock_error(skb, ECANCELED, SO_EE_CODE_TXTIME_MISSED); |
25db26a9 | 221 | |
37342bda JSP |
222 | qdisc_qstats_backlog_dec(sch, skb); |
223 | qdisc_drop(skb, sch, &to_free); | |
224 | qdisc_qstats_overlimit(sch); | |
225 | sch->q.qlen--; | |
226 | } | |
4b15c707 | 227 | |
37342bda | 228 | kfree_skb_list(to_free); |
cbeeb8ef | 229 | } |
25db26a9 | 230 | |
cbeeb8ef JSP |
231 | static void timesortedlist_remove(struct Qdisc *sch, struct sk_buff *skb) |
232 | { | |
233 | struct etf_sched_data *q = qdisc_priv(sch); | |
234 | ||
235 | rb_erase_cached(&skb->rbnode, &q->head); | |
236 | ||
237 | /* The rbnode field in the skb re-uses these fields, now that | |
238 | * we are done with the rbnode, reset them. | |
239 | */ | |
240 | skb->next = NULL; | |
241 | skb->prev = NULL; | |
242 | skb->dev = qdisc_dev(sch); | |
243 | ||
244 | qdisc_qstats_backlog_dec(sch, skb); | |
245 | ||
246 | qdisc_bstats_update(sch, skb); | |
247 | ||
248 | q->last = skb->tstamp; | |
25db26a9 VCG |
249 | |
250 | sch->q.qlen--; | |
251 | } | |
252 | ||
253 | static struct sk_buff *etf_dequeue_timesortedlist(struct Qdisc *sch) | |
254 | { | |
255 | struct etf_sched_data *q = qdisc_priv(sch); | |
256 | struct sk_buff *skb; | |
257 | ktime_t now, next; | |
258 | ||
259 | skb = etf_peek_timesortedlist(sch); | |
260 | if (!skb) | |
261 | return NULL; | |
262 | ||
263 | now = q->get_time(); | |
264 | ||
265 | /* Drop if packet has expired while in queue. */ | |
25db26a9 | 266 | if (ktime_before(skb->tstamp, now)) { |
37342bda | 267 | timesortedlist_drop(sch, skb, now); |
25db26a9 VCG |
268 | skb = NULL; |
269 | goto out; | |
270 | } | |
271 | ||
272 | /* When in deadline mode, dequeue as soon as possible and change the | |
273 | * txtime from deadline to (now + delta). | |
274 | */ | |
275 | if (q->deadline_mode) { | |
cbeeb8ef | 276 | timesortedlist_remove(sch, skb); |
25db26a9 VCG |
277 | skb->tstamp = now; |
278 | goto out; | |
279 | } | |
280 | ||
281 | next = ktime_sub_ns(skb->tstamp, q->delta); | |
282 | ||
283 | /* Dequeue only if now is within the [txtime - delta, txtime] range. */ | |
284 | if (ktime_after(now, next)) | |
cbeeb8ef | 285 | timesortedlist_remove(sch, skb); |
25db26a9 VCG |
286 | else |
287 | skb = NULL; | |
288 | ||
289 | out: | |
290 | /* Now we may need to re-arm the qdisc watchdog for the next packet. */ | |
291 | reset_watchdog(sch); | |
292 | ||
293 | return skb; | |
294 | } | |
295 | ||
88cab771 JSP |
296 | static void etf_disable_offload(struct net_device *dev, |
297 | struct etf_sched_data *q) | |
298 | { | |
299 | struct tc_etf_qopt_offload etf = { }; | |
300 | const struct net_device_ops *ops; | |
301 | int err; | |
302 | ||
303 | if (!q->offload) | |
304 | return; | |
305 | ||
306 | ops = dev->netdev_ops; | |
307 | if (!ops->ndo_setup_tc) | |
308 | return; | |
309 | ||
310 | etf.queue = q->queue; | |
311 | etf.enable = 0; | |
312 | ||
313 | err = ops->ndo_setup_tc(dev, TC_SETUP_QDISC_ETF, &etf); | |
314 | if (err < 0) | |
315 | pr_warn("Couldn't disable ETF offload for queue %d\n", | |
316 | etf.queue); | |
317 | } | |
318 | ||
319 | static int etf_enable_offload(struct net_device *dev, struct etf_sched_data *q, | |
320 | struct netlink_ext_ack *extack) | |
321 | { | |
322 | const struct net_device_ops *ops = dev->netdev_ops; | |
323 | struct tc_etf_qopt_offload etf = { }; | |
324 | int err; | |
325 | ||
88cab771 JSP |
326 | if (!ops->ndo_setup_tc) { |
327 | NL_SET_ERR_MSG(extack, "Specified device does not support ETF offload"); | |
328 | return -EOPNOTSUPP; | |
329 | } | |
330 | ||
331 | etf.queue = q->queue; | |
332 | etf.enable = 1; | |
333 | ||
334 | err = ops->ndo_setup_tc(dev, TC_SETUP_QDISC_ETF, &etf); | |
335 | if (err < 0) { | |
336 | NL_SET_ERR_MSG(extack, "Specified device failed to setup ETF hardware offload"); | |
337 | return err; | |
338 | } | |
339 | ||
340 | return 0; | |
341 | } | |
342 | ||
25db26a9 VCG |
343 | static int etf_init(struct Qdisc *sch, struct nlattr *opt, |
344 | struct netlink_ext_ack *extack) | |
345 | { | |
346 | struct etf_sched_data *q = qdisc_priv(sch); | |
347 | struct net_device *dev = qdisc_dev(sch); | |
348 | struct nlattr *tb[TCA_ETF_MAX + 1]; | |
349 | struct tc_etf_qopt *qopt; | |
350 | int err; | |
351 | ||
352 | if (!opt) { | |
353 | NL_SET_ERR_MSG(extack, | |
354 | "Missing ETF qdisc options which are mandatory"); | |
355 | return -EINVAL; | |
356 | } | |
357 | ||
8cb08174 JB |
358 | err = nla_parse_nested_deprecated(tb, TCA_ETF_MAX, opt, etf_policy, |
359 | extack); | |
25db26a9 VCG |
360 | if (err < 0) |
361 | return err; | |
362 | ||
363 | if (!tb[TCA_ETF_PARMS]) { | |
364 | NL_SET_ERR_MSG(extack, "Missing mandatory ETF parameters"); | |
365 | return -EINVAL; | |
366 | } | |
367 | ||
368 | qopt = nla_data(tb[TCA_ETF_PARMS]); | |
369 | ||
88cab771 | 370 | pr_debug("delta %d clockid %d offload %s deadline %s\n", |
25db26a9 | 371 | qopt->delta, qopt->clockid, |
88cab771 | 372 | OFFLOAD_IS_ON(qopt) ? "on" : "off", |
25db26a9 VCG |
373 | DEADLINE_MODE_IS_ON(qopt) ? "on" : "off"); |
374 | ||
375 | err = validate_input_params(qopt, extack); | |
376 | if (err < 0) | |
377 | return err; | |
378 | ||
379 | q->queue = sch->dev_queue - netdev_get_tx_queue(dev, 0); | |
380 | ||
88cab771 JSP |
381 | if (OFFLOAD_IS_ON(qopt)) { |
382 | err = etf_enable_offload(dev, q, extack); | |
383 | if (err < 0) | |
384 | return err; | |
385 | } | |
386 | ||
25db26a9 VCG |
387 | /* Everything went OK, save the parameters used. */ |
388 | q->delta = qopt->delta; | |
389 | q->clockid = qopt->clockid; | |
88cab771 | 390 | q->offload = OFFLOAD_IS_ON(qopt); |
25db26a9 | 391 | q->deadline_mode = DEADLINE_MODE_IS_ON(qopt); |
d14d2b20 | 392 | q->skip_sock_check = SKIP_SOCK_CHECK_IS_SET(qopt); |
25db26a9 VCG |
393 | |
394 | switch (q->clockid) { | |
395 | case CLOCK_REALTIME: | |
396 | q->get_time = ktime_get_real; | |
397 | break; | |
398 | case CLOCK_MONOTONIC: | |
399 | q->get_time = ktime_get; | |
400 | break; | |
401 | case CLOCK_BOOTTIME: | |
402 | q->get_time = ktime_get_boottime; | |
403 | break; | |
404 | case CLOCK_TAI: | |
405 | q->get_time = ktime_get_clocktai; | |
406 | break; | |
407 | default: | |
408 | NL_SET_ERR_MSG(extack, "Clockid is not supported"); | |
409 | return -ENOTSUPP; | |
410 | } | |
411 | ||
412 | qdisc_watchdog_init_clockid(&q->watchdog, sch, q->clockid); | |
413 | ||
414 | return 0; | |
415 | } | |
416 | ||
417 | static void timesortedlist_clear(struct Qdisc *sch) | |
418 | { | |
419 | struct etf_sched_data *q = qdisc_priv(sch); | |
09fd4860 | 420 | struct rb_node *p = rb_first_cached(&q->head); |
25db26a9 VCG |
421 | |
422 | while (p) { | |
423 | struct sk_buff *skb = rb_to_skb(p); | |
424 | ||
425 | p = rb_next(p); | |
426 | ||
09fd4860 | 427 | rb_erase_cached(&skb->rbnode, &q->head); |
25db26a9 VCG |
428 | rtnl_kfree_skbs(skb, skb); |
429 | sch->q.qlen--; | |
430 | } | |
431 | } | |
432 | ||
433 | static void etf_reset(struct Qdisc *sch) | |
434 | { | |
435 | struct etf_sched_data *q = qdisc_priv(sch); | |
436 | ||
437 | /* Only cancel watchdog if it's been initialized. */ | |
438 | if (q->watchdog.qdisc == sch) | |
439 | qdisc_watchdog_cancel(&q->watchdog); | |
440 | ||
441 | /* No matter which mode we are on, it's safe to clear both lists. */ | |
442 | timesortedlist_clear(sch); | |
443 | __qdisc_reset_queue(&sch->q); | |
444 | ||
25db26a9 VCG |
445 | q->last = 0; |
446 | } | |
447 | ||
448 | static void etf_destroy(struct Qdisc *sch) | |
449 | { | |
450 | struct etf_sched_data *q = qdisc_priv(sch); | |
88cab771 | 451 | struct net_device *dev = qdisc_dev(sch); |
25db26a9 VCG |
452 | |
453 | /* Only cancel watchdog if it's been initialized. */ | |
454 | if (q->watchdog.qdisc == sch) | |
455 | qdisc_watchdog_cancel(&q->watchdog); | |
88cab771 JSP |
456 | |
457 | etf_disable_offload(dev, q); | |
25db26a9 VCG |
458 | } |
459 | ||
460 | static int etf_dump(struct Qdisc *sch, struct sk_buff *skb) | |
461 | { | |
462 | struct etf_sched_data *q = qdisc_priv(sch); | |
463 | struct tc_etf_qopt opt = { }; | |
464 | struct nlattr *nest; | |
465 | ||
ae0be8de | 466 | nest = nla_nest_start_noflag(skb, TCA_OPTIONS); |
25db26a9 VCG |
467 | if (!nest) |
468 | goto nla_put_failure; | |
469 | ||
470 | opt.delta = q->delta; | |
471 | opt.clockid = q->clockid; | |
88cab771 JSP |
472 | if (q->offload) |
473 | opt.flags |= TC_ETF_OFFLOAD_ON; | |
474 | ||
25db26a9 VCG |
475 | if (q->deadline_mode) |
476 | opt.flags |= TC_ETF_DEADLINE_MODE_ON; | |
477 | ||
d14d2b20 VP |
478 | if (q->skip_sock_check) |
479 | opt.flags |= TC_ETF_SKIP_SOCK_CHECK; | |
480 | ||
25db26a9 VCG |
481 | if (nla_put(skb, TCA_ETF_PARMS, sizeof(opt), &opt)) |
482 | goto nla_put_failure; | |
483 | ||
484 | return nla_nest_end(skb, nest); | |
485 | ||
486 | nla_put_failure: | |
487 | nla_nest_cancel(skb, nest); | |
488 | return -1; | |
489 | } | |
490 | ||
491 | static struct Qdisc_ops etf_qdisc_ops __read_mostly = { | |
492 | .id = "etf", | |
493 | .priv_size = sizeof(struct etf_sched_data), | |
494 | .enqueue = etf_enqueue_timesortedlist, | |
495 | .dequeue = etf_dequeue_timesortedlist, | |
496 | .peek = etf_peek_timesortedlist, | |
497 | .init = etf_init, | |
498 | .reset = etf_reset, | |
499 | .destroy = etf_destroy, | |
500 | .dump = etf_dump, | |
501 | .owner = THIS_MODULE, | |
502 | }; | |
503 | ||
504 | static int __init etf_module_init(void) | |
505 | { | |
506 | return register_qdisc(&etf_qdisc_ops); | |
507 | } | |
508 | ||
509 | static void __exit etf_module_exit(void) | |
510 | { | |
511 | unregister_qdisc(&etf_qdisc_ops); | |
512 | } | |
513 | module_init(etf_module_init) | |
514 | module_exit(etf_module_exit) | |
515 | MODULE_LICENSE("GPL"); |