Whamcloud - gitweb
LU-7243 misc: update Intel copyright messages 2015
[fs/lustre-release.git] / lnet / lnet / net_fault.c
1 /*
2  * GPL HEADER START
3  *
4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 only,
8  * as published by the Free Software Foundation.
9  *
10  * This program is distributed in the hope that it will be useful, but
11  * WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13  * General Public License version 2 for more details (a copy is included
14  * in the LICENSE file that accompanied this code).
15  *
16  * You should have received a copy of the GNU General Public License
17  * version 2 along with this program; if not, write to the
18  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
19  * Boston, MA 021110-1307, USA
20  *
21  * GPL HEADER END
22  */
23 /*
24  * Copyright (c) 2014, Intel Corporation.
25  */
26 /*
27  * This file is part of Lustre, http://www.lustre.org/
28  * Lustre is a trademark of Sun Microsystems, Inc.
29  *
30  * lnet/lnet/net_fault.c
31  *
32  * Lustre network fault simulation
33  *
34  * Author: liang.zhen@intel.com
35  */
36
37 #define DEBUG_SUBSYSTEM S_LNET
38
39 #include <lnet/lib-lnet.h>
40 #include <lnet/lnetctl.h>
41
42 #define LNET_MSG_MASK           (LNET_PUT_BIT | LNET_ACK_BIT | \
43                                  LNET_GET_BIT | LNET_REPLY_BIT)
44
45 struct lnet_drop_rule {
46         /** link chain on the_lnet.ln_drop_rules */
47         struct list_head        dr_link;
48         /** attributes of this rule */
49         struct lnet_fault_attr  dr_attr;
50         /** lock to protect \a dr_drop_at and \a dr_stat */
51         spinlock_t              dr_lock;
52         /**
53          * the message sequence to drop, which means message is dropped when
54          * dr_stat.drs_count == dr_drop_at
55          */
56         unsigned long           dr_drop_at;
57         /**
58          * seconds to drop the next message, it's exclusive with dr_drop_at
59          */
60         cfs_time_t              dr_drop_time;
61         /** baseline to caculate dr_drop_time */
62         cfs_time_t              dr_time_base;
63         /** statistic of dropped messages */
64         struct lnet_fault_stat  dr_stat;
65 };
66
67 static bool
68 lnet_fault_nid_match(lnet_nid_t nid, lnet_nid_t msg_nid)
69 {
70         if (nid == msg_nid || nid == LNET_NID_ANY)
71                 return true;
72
73         if (LNET_NIDNET(nid) != LNET_NIDNET(msg_nid))
74                 return false;
75
76         /* 255.255.255.255@net is wildcard for all addresses in a network */
77         return LNET_NIDADDR(nid) == LNET_NIDADDR(LNET_NID_ANY);
78 }
79
80 static bool
81 lnet_fault_attr_match(struct lnet_fault_attr *attr, lnet_nid_t src,
82                       lnet_nid_t dst, unsigned int type, unsigned int portal)
83 {
84         if (!lnet_fault_nid_match(attr->fa_src, src) ||
85             !lnet_fault_nid_match(attr->fa_dst, dst))
86                 return false;
87
88         if (!(attr->fa_msg_mask & (1 << type)))
89                 return false;
90
91         /* NB: ACK and REPLY have no portal, but they should have been
92          * rejected by message mask */
93         if (attr->fa_ptl_mask != 0 && /* has portal filter */
94             !(attr->fa_ptl_mask & (1ULL << portal)))
95                 return false;
96
97         return true;
98 }
99
100 static int
101 lnet_fault_attr_validate(struct lnet_fault_attr *attr)
102 {
103         if (attr->fa_msg_mask == 0)
104                 attr->fa_msg_mask = LNET_MSG_MASK; /* all message types */
105
106         if (attr->fa_ptl_mask == 0) /* no portal filter */
107                 return 0;
108
109         /* NB: only PUT and GET can be filtered if portal filter has been set */
110         attr->fa_msg_mask &= LNET_GET_BIT | LNET_PUT_BIT;
111         if (attr->fa_msg_mask == 0) {
112                 CDEBUG(D_NET, "can't find valid message type bits %x\n",
113                        attr->fa_msg_mask);
114                 return -EINVAL;
115         }
116         return 0;
117 }
118
119 static void
120 lnet_fault_stat_inc(struct lnet_fault_stat *stat, unsigned int type)
121 {
122         /* NB: fs_counter is NOT updated by this function */
123         switch (type) {
124         case LNET_MSG_PUT:
125                 stat->fs_put++;
126                 return;
127         case LNET_MSG_ACK:
128                 stat->fs_ack++;
129                 return;
130         case LNET_MSG_GET:
131                 stat->fs_get++;
132                 return;
133         case LNET_MSG_REPLY:
134                 stat->fs_reply++;
135                 return;
136         }
137 }
138
139 /**
140  * LNet message drop simulation
141  */
142
143 /**
144  * Add a new drop rule to LNet
145  * There is no check for duplicated drop rule, all rules will be checked for
146  * incoming message.
147  */
148 static int
149 lnet_drop_rule_add(struct lnet_fault_attr *attr)
150 {
151         struct lnet_drop_rule *rule;
152         ENTRY;
153
154         if (!((attr->u.drop.da_rate == 0) ^ (attr->u.drop.da_interval == 0))) {
155                 CDEBUG(D_NET,
156                        "please provide either drop rate or drop interval, "
157                        "but not both at the same time %d/%d\n",
158                        attr->u.drop.da_rate, attr->u.drop.da_interval);
159                 RETURN(-EINVAL);
160         }
161
162         if (lnet_fault_attr_validate(attr) != 0)
163                 RETURN(-EINVAL);
164
165         CFS_ALLOC_PTR(rule);
166         if (rule == NULL)
167                 RETURN(-ENOMEM);
168
169         spin_lock_init(&rule->dr_lock);
170
171         rule->dr_attr = *attr;
172         if (attr->u.drop.da_interval != 0) {
173                 rule->dr_time_base = cfs_time_shift(attr->u.drop.da_interval);
174                 rule->dr_drop_time = cfs_time_shift(cfs_rand() %
175                                                     attr->u.drop.da_interval);
176         } else {
177                 rule->dr_drop_at = cfs_rand() % attr->u.drop.da_rate;
178         }
179
180         lnet_net_lock(LNET_LOCK_EX);
181         list_add(&rule->dr_link, &the_lnet.ln_drop_rules);
182         lnet_net_unlock(LNET_LOCK_EX);
183
184         CDEBUG(D_NET, "Added drop rule: src %s, dst %s, rate %d, interval %d\n",
185                libcfs_nid2str(attr->fa_src), libcfs_nid2str(attr->fa_src),
186                attr->u.drop.da_rate, attr->u.drop.da_interval);
187         RETURN(0);
188 }
189
190 /**
191  * Remove matched drop rules from lnet, all rules that can match \a src and
192  * \a dst will be removed.
193  * If \a src is zero, then all rules have \a dst as destination will be remove
194  * If \a dst is zero, then all rules have \a src as source will be removed
195  * If both of them are zero, all rules will be removed
196  */
197 static int
198 lnet_drop_rule_del(lnet_nid_t src, lnet_nid_t dst)
199 {
200         struct lnet_drop_rule *rule;
201         struct lnet_drop_rule *tmp;
202         struct list_head       zombies;
203         int                    n = 0;
204         ENTRY;
205
206         INIT_LIST_HEAD(&zombies);
207
208         lnet_net_lock(LNET_LOCK_EX);
209         list_for_each_entry_safe(rule, tmp, &the_lnet.ln_drop_rules, dr_link) {
210                 if (rule->dr_attr.fa_src != src && src != 0)
211                         continue;
212
213                 if (rule->dr_attr.fa_dst != dst && dst != 0)
214                         continue;
215
216                 list_move(&rule->dr_link, &zombies);
217         }
218         lnet_net_unlock(LNET_LOCK_EX);
219
220         list_for_each_entry_safe(rule, tmp, &zombies, dr_link) {
221                 CDEBUG(D_NET, "Remove drop rule: src %s->dst: %s (1/%d, %d)\n",
222                        libcfs_nid2str(rule->dr_attr.fa_src),
223                        libcfs_nid2str(rule->dr_attr.fa_dst),
224                        rule->dr_attr.u.drop.da_rate,
225                        rule->dr_attr.u.drop.da_interval);
226
227                 list_del(&rule->dr_link);
228                 CFS_FREE_PTR(rule);
229                 n++;
230         }
231
232         RETURN(n);
233 }
234
235 /**
236  * List drop rule at position of \a pos
237  */
238 static int
239 lnet_drop_rule_list(int pos, struct lnet_fault_attr *attr,
240                     struct lnet_fault_stat *stat)
241 {
242         struct lnet_drop_rule *rule;
243         int                    cpt;
244         int                    i = 0;
245         int                    rc = -ENOENT;
246         ENTRY;
247
248         cpt = lnet_net_lock_current();
249         list_for_each_entry(rule, &the_lnet.ln_drop_rules, dr_link) {
250                 if (i++ < pos)
251                         continue;
252
253                 spin_lock(&rule->dr_lock);
254                 *attr = rule->dr_attr;
255                 *stat = rule->dr_stat;
256                 spin_unlock(&rule->dr_lock);
257                 rc = 0;
258                 break;
259         }
260
261         lnet_net_unlock(cpt);
262         RETURN(rc);
263 }
264
265 /**
266  * reset counters for all drop rules
267  */
268 static void
269 lnet_drop_rule_reset(void)
270 {
271         struct lnet_drop_rule *rule;
272         int                    cpt;
273         ENTRY;
274
275         cpt = lnet_net_lock_current();
276
277         list_for_each_entry(rule, &the_lnet.ln_drop_rules, dr_link) {
278                 struct lnet_fault_attr *attr = &rule->dr_attr;
279
280                 spin_lock(&rule->dr_lock);
281
282                 memset(&rule->dr_stat, 0, sizeof(rule->dr_stat));
283                 if (attr->u.drop.da_rate != 0) {
284                         rule->dr_drop_at = cfs_rand() % attr->u.drop.da_rate;
285                 } else {
286                         rule->dr_drop_time = cfs_time_shift(cfs_rand() %
287                                                 attr->u.drop.da_interval);
288                         rule->dr_time_base = cfs_time_shift(attr->u.drop.
289                                                                   da_interval);
290                 }
291                 spin_unlock(&rule->dr_lock);
292         }
293
294         lnet_net_unlock(cpt);
295         EXIT;
296 }
297
298 /**
299  * check source/destination NID, portal, message type and drop rate,
300  * decide whether should drop this message or not
301  */
302 static bool
303 drop_rule_match(struct lnet_drop_rule *rule, lnet_nid_t src,
304                 lnet_nid_t dst, unsigned int type, unsigned int portal)
305 {
306         struct lnet_fault_attr  *attr = &rule->dr_attr;
307         bool                     drop;
308
309         if (!lnet_fault_attr_match(attr, src, dst, type, portal))
310                 return false;
311
312         /* match this rule, check drop rate now */
313         spin_lock(&rule->dr_lock);
314         if (rule->dr_drop_time != 0) { /* time based drop */
315                 cfs_time_t now = cfs_time_current();
316
317                 rule->dr_stat.fs_count++;
318                 drop = cfs_time_aftereq(now, rule->dr_drop_time);
319                 if (drop) {
320                         if (cfs_time_after(now, rule->dr_time_base))
321                                 rule->dr_time_base = now;
322
323                         rule->dr_drop_time = rule->dr_time_base +
324                                              cfs_time_seconds(cfs_rand() %
325                                                 attr->u.drop.da_interval);
326                         rule->dr_time_base += cfs_time_seconds(attr->u.drop.
327                                                                da_interval);
328
329                         CDEBUG(D_NET, "Drop Rule %s->%s: next drop : "
330                                       CFS_TIME_T"\n",
331                                       libcfs_nid2str(attr->fa_src),
332                                       libcfs_nid2str(attr->fa_dst),
333                                       rule->dr_drop_time);
334                 }
335
336         } else { /* rate based drop */
337                 drop = rule->dr_stat.fs_count++ == rule->dr_drop_at;
338
339                 if (rule->dr_stat.fs_count % attr->u.drop.da_rate == 0) {
340                         rule->dr_drop_at = rule->dr_stat.fs_count +
341                                            cfs_rand() % attr->u.drop.da_rate;
342                         CDEBUG(D_NET, "Drop Rule %s->%s: next drop: %lu\n",
343                                libcfs_nid2str(attr->fa_src),
344                                libcfs_nid2str(attr->fa_dst), rule->dr_drop_at);
345                 }
346         }
347
348         if (drop) { /* drop this message, update counters */
349                 lnet_fault_stat_inc(&rule->dr_stat, type);
350                 rule->dr_stat.u.drop.ds_dropped++;
351         }
352
353         spin_unlock(&rule->dr_lock);
354         return drop;
355 }
356
357 /**
358  * Check if message from \a src to \a dst can match any existed drop rule
359  */
360 bool
361 lnet_drop_rule_match(lnet_hdr_t *hdr)
362 {
363         struct lnet_drop_rule   *rule;
364         lnet_nid_t               src = le64_to_cpu(hdr->src_nid);
365         lnet_nid_t               dst = le64_to_cpu(hdr->dest_nid);
366         unsigned int             typ = le32_to_cpu(hdr->type);
367         unsigned int             ptl = -1;
368         bool                     drop = false;
369         int                      cpt;
370
371         /* NB: if Portal is specified, then only PUT and GET will be
372          * filtered by drop rule */
373         if (typ == LNET_MSG_PUT)
374                 ptl = le32_to_cpu(hdr->msg.put.ptl_index);
375         else if (typ == LNET_MSG_GET)
376                 ptl = le32_to_cpu(hdr->msg.get.ptl_index);
377
378         cpt = lnet_net_lock_current();
379         list_for_each_entry(rule, &the_lnet.ln_drop_rules, dr_link) {
380                 drop = drop_rule_match(rule, src, dst, typ, ptl);
381                 if (drop)
382                         break;
383         }
384
385         lnet_net_unlock(cpt);
386         return drop;
387 }
388
389 /**
390  * LNet Delay Simulation
391  */
392 /** timestamp (second) to send delayed message */
393 #define msg_delay_send           msg_ev.hdr_data
394
395 struct lnet_delay_rule {
396         /** link chain on the_lnet.ln_delay_rules */
397         struct list_head        dl_link;
398         /** link chain on delay_dd.dd_sched_rules */
399         struct list_head        dl_sched_link;
400         /** attributes of this rule */
401         struct lnet_fault_attr  dl_attr;
402         /** lock to protect \a below members */
403         spinlock_t              dl_lock;
404         /** refcount of delay rule */
405         atomic_t                dl_refcount;
406         /**
407          * the message sequence to delay, which means message is delayed when
408          * dl_stat.fs_count == dl_delay_at
409          */
410         unsigned long           dl_delay_at;
411         /**
412          * seconds to delay the next message, it's exclusive with dl_delay_at
413          */
414         cfs_time_t              dl_delay_time;
415         /** baseline to caculate dl_delay_time */
416         cfs_time_t              dl_time_base;
417         /** jiffies to send the next delayed message */
418         unsigned long           dl_msg_send;
419         /** delayed message list */
420         struct list_head        dl_msg_list;
421         /** statistic of delayed messages */
422         struct lnet_fault_stat  dl_stat;
423         /** timer to wakeup delay_daemon */
424         struct timer_list       dl_timer;
425 };
426
427 struct delay_daemon_data {
428         /** serialise rule add/remove */
429         struct mutex            dd_mutex;
430         /** protect rules on \a dd_sched_rules */
431         spinlock_t              dd_lock;
432         /** scheduled delay rules (by timer) */
433         struct list_head        dd_sched_rules;
434         /** deamon thread sleeps at here */
435         wait_queue_head_t       dd_waitq;
436         /** controler (lctl command) wait at here */
437         wait_queue_head_t       dd_ctl_waitq;
438         /** deamon is running */
439         unsigned int            dd_running;
440         /** deamon stopped */
441         unsigned int            dd_stopped;
442 };
443
444 static struct delay_daemon_data delay_dd;
445
446 static cfs_time_t
447 round_timeout(cfs_time_t timeout)
448 {
449         return cfs_time_seconds((unsigned int)
450                         cfs_duration_sec(cfs_time_sub(timeout, 0)) + 1);
451 }
452
453 static void
454 delay_rule_decref(struct lnet_delay_rule *rule)
455 {
456         if (atomic_dec_and_test(&rule->dl_refcount)) {
457                 LASSERT(list_empty(&rule->dl_sched_link));
458                 LASSERT(list_empty(&rule->dl_msg_list));
459                 LASSERT(list_empty(&rule->dl_link));
460
461                 CFS_FREE_PTR(rule);
462         }
463 }
464
465 /**
466  * check source/destination NID, portal, message type and delay rate,
467  * decide whether should delay this message or not
468  */
469 static bool
470 delay_rule_match(struct lnet_delay_rule *rule, lnet_nid_t src,
471                 lnet_nid_t dst, unsigned int type, unsigned int portal,
472                 struct lnet_msg *msg)
473 {
474         struct lnet_fault_attr  *attr = &rule->dl_attr;
475         bool                     delay;
476
477         if (!lnet_fault_attr_match(attr, src, dst, type, portal))
478                 return false;
479
480         /* match this rule, check delay rate now */
481         spin_lock(&rule->dl_lock);
482         if (rule->dl_delay_time != 0) { /* time based delay */
483                 cfs_time_t now = cfs_time_current();
484
485                 rule->dl_stat.fs_count++;
486                 delay = cfs_time_aftereq(now, rule->dl_delay_time);
487                 if (delay) {
488                         if (cfs_time_after(now, rule->dl_time_base))
489                                 rule->dl_time_base = now;
490
491                         rule->dl_delay_time = rule->dl_time_base +
492                                              cfs_time_seconds(cfs_rand() %
493                                                 attr->u.delay.la_interval);
494                         rule->dl_time_base += cfs_time_seconds(attr->u.delay.
495                                                                la_interval);
496
497                         CDEBUG(D_NET, "Delay Rule %s->%s: next delay : "
498                                       CFS_TIME_T"\n",
499                                       libcfs_nid2str(attr->fa_src),
500                                       libcfs_nid2str(attr->fa_dst),
501                                       rule->dl_delay_time);
502                 }
503
504         } else { /* rate based delay */
505                 delay = rule->dl_stat.fs_count++ == rule->dl_delay_at;
506                 /* generate the next random rate sequence */
507                 if (rule->dl_stat.fs_count % attr->u.delay.la_rate == 0) {
508                         rule->dl_delay_at = rule->dl_stat.fs_count +
509                                             cfs_rand() % attr->u.delay.la_rate;
510                         CDEBUG(D_NET, "Delay Rule %s->%s: next delay: %lu\n",
511                                libcfs_nid2str(attr->fa_src),
512                                libcfs_nid2str(attr->fa_dst), rule->dl_delay_at);
513                 }
514         }
515
516         if (!delay) {
517                 spin_unlock(&rule->dl_lock);
518                 return false;
519         }
520
521         /* delay this message, update counters */
522         lnet_fault_stat_inc(&rule->dl_stat, type);
523         rule->dl_stat.u.delay.ls_delayed++;
524
525         list_add_tail(&msg->msg_list, &rule->dl_msg_list);
526         msg->msg_delay_send = round_timeout(
527                         cfs_time_shift(attr->u.delay.la_latency));
528         if (rule->dl_msg_send == -1) {
529                 rule->dl_msg_send = msg->msg_delay_send;
530                 mod_timer(&rule->dl_timer, rule->dl_msg_send);
531         }
532
533         spin_unlock(&rule->dl_lock);
534         return true;
535 }
536
537 /**
538  * check if \a msg can match any Delay Rule, receiving of this message
539  * will be delayed if there is a match.
540  */
541 bool
542 lnet_delay_rule_match_locked(lnet_hdr_t *hdr, struct lnet_msg *msg)
543 {
544         struct lnet_delay_rule  *rule;
545         lnet_nid_t               src = le64_to_cpu(hdr->src_nid);
546         lnet_nid_t               dst = le64_to_cpu(hdr->dest_nid);
547         unsigned int             typ = le32_to_cpu(hdr->type);
548         unsigned int             ptl = -1;
549
550         /* NB: called with hold of lnet_net_lock */
551
552         /* NB: if Portal is specified, then only PUT and GET will be
553          * filtered by delay rule */
554         if (typ == LNET_MSG_PUT)
555                 ptl = le32_to_cpu(hdr->msg.put.ptl_index);
556         else if (typ == LNET_MSG_GET)
557                 ptl = le32_to_cpu(hdr->msg.get.ptl_index);
558
559         list_for_each_entry(rule, &the_lnet.ln_delay_rules, dl_link) {
560                 if (delay_rule_match(rule, src, dst, typ, ptl, msg))
561                         return true;
562         }
563
564         return false;
565 }
566
567 /** check out delayed messages for send */
568 static void
569 delayed_msg_check(struct lnet_delay_rule *rule, bool all,
570                   struct list_head *msg_list)
571 {
572         struct lnet_msg *msg;
573         struct lnet_msg *tmp;
574         unsigned long    now = cfs_time_current();
575
576         if (!all && rule->dl_msg_send > now)
577                 return;
578
579         spin_lock(&rule->dl_lock);
580         list_for_each_entry_safe(msg, tmp, &rule->dl_msg_list, msg_list) {
581                 if (!all && msg->msg_delay_send > now)
582                         break;
583
584                 msg->msg_delay_send = 0;
585                 list_move_tail(&msg->msg_list, msg_list);
586         }
587
588         if (list_empty(&rule->dl_msg_list)) {
589                 del_timer(&rule->dl_timer);
590                 rule->dl_msg_send = -1;
591
592         } else if (!list_empty(msg_list)) {
593                 /* dequeued some timedout messages, update timer for the
594                  * next delayed message on rule */
595                 msg = list_entry(rule->dl_msg_list.next,
596                                  struct lnet_msg, msg_list);
597                 rule->dl_msg_send = msg->msg_delay_send;
598                 mod_timer(&rule->dl_timer, rule->dl_msg_send);
599         }
600         spin_unlock(&rule->dl_lock);
601 }
602
603 static void
604 delayed_msg_process(struct list_head *msg_list, bool drop)
605 {
606         struct lnet_msg *msg;
607
608         while (!list_empty(msg_list)) {
609                 struct lnet_ni *ni;
610                 int             cpt;
611                 int             rc;
612
613                 msg = list_entry(msg_list->next, struct lnet_msg, msg_list);
614                 LASSERT(msg->msg_rxpeer != NULL);
615
616                 ni = msg->msg_rxpeer->lp_ni;
617                 cpt = msg->msg_rx_cpt;
618
619                 list_del_init(&msg->msg_list);
620                 if (drop) {
621                         rc = -ECANCELED;
622
623                 } else if (!msg->msg_routing) {
624                         rc = lnet_parse_local(ni, msg);
625                         if (rc == 0)
626                                 continue;
627
628                 } else {
629                         lnet_net_lock(cpt);
630                         rc = lnet_parse_forward_locked(ni, msg);
631                         lnet_net_unlock(cpt);
632
633                         switch (rc) {
634                         case LNET_CREDIT_OK:
635                                 lnet_ni_recv(ni, msg->msg_private, msg, 0,
636                                              0, msg->msg_len, msg->msg_len);
637                         case LNET_CREDIT_WAIT:
638                                 continue;
639                         default: /* failures */
640                                 break;
641                         }
642                 }
643
644                 lnet_drop_message(ni, cpt, msg->msg_private, msg->msg_len);
645                 lnet_finalize(ni, msg, rc);
646         }
647 }
648
649 /**
650  * Process delayed messages for scheduled rules
651  * This function can either be called by delay_rule_daemon, or by lnet_finalise
652  */
653 void
654 lnet_delay_rule_check(void)
655 {
656         struct lnet_delay_rule  *rule;
657         struct list_head         msgs;
658
659         INIT_LIST_HEAD(&msgs);
660         while (1) {
661                 if (list_empty(&delay_dd.dd_sched_rules))
662                         break;
663
664                 spin_lock_bh(&delay_dd.dd_lock);
665                 if (list_empty(&delay_dd.dd_sched_rules)) {
666                         spin_unlock_bh(&delay_dd.dd_lock);
667                         break;
668                 }
669
670                 rule = list_entry(delay_dd.dd_sched_rules.next,
671                                   struct lnet_delay_rule, dl_sched_link);
672                 list_del_init(&rule->dl_sched_link);
673                 spin_unlock_bh(&delay_dd.dd_lock);
674
675                 delayed_msg_check(rule, false, &msgs);
676                 delay_rule_decref(rule); /* -1 for delay_dd.dd_sched_rules */
677         }
678
679         if (!list_empty(&msgs))
680                 delayed_msg_process(&msgs, false);
681 }
682
683 /** deamon thread to handle delayed messages */
684 static int
685 lnet_delay_rule_daemon(void *arg)
686 {
687         delay_dd.dd_running = 1;
688         wake_up(&delay_dd.dd_ctl_waitq);
689
690         while (delay_dd.dd_running) {
691                 wait_event_interruptible(delay_dd.dd_waitq,
692                                          !delay_dd.dd_running ||
693                                          !list_empty(&delay_dd.dd_sched_rules));
694                 lnet_delay_rule_check();
695         }
696
697         /* in case more rules have been enqueued after my last check */
698         lnet_delay_rule_check();
699         delay_dd.dd_stopped = 1;
700         wake_up(&delay_dd.dd_ctl_waitq);
701
702         return 0;
703 }
704
705 static void
706 delay_timer_cb(unsigned long arg)
707 {
708         struct lnet_delay_rule *rule = (struct lnet_delay_rule *)arg;
709
710         spin_lock_bh(&delay_dd.dd_lock);
711         if (list_empty(&rule->dl_sched_link) && delay_dd.dd_running) {
712                 atomic_inc(&rule->dl_refcount);
713                 list_add_tail(&rule->dl_sched_link, &delay_dd.dd_sched_rules);
714                 wake_up(&delay_dd.dd_waitq);
715         }
716         spin_unlock_bh(&delay_dd.dd_lock);
717 }
718
719 /**
720  * Add a new delay rule to LNet
721  * There is no check for duplicated delay rule, all rules will be checked for
722  * incoming message.
723  */
724 int
725 lnet_delay_rule_add(struct lnet_fault_attr *attr)
726 {
727         struct lnet_delay_rule *rule;
728         int                     rc = 0;
729         ENTRY;
730
731         if (!((attr->u.delay.la_rate == 0) ^
732               (attr->u.delay.la_interval == 0))) {
733                 CDEBUG(D_NET,
734                        "please provide either delay rate or delay interval, "
735                        "but not both at the same time %d/%d\n",
736                        attr->u.delay.la_rate, attr->u.delay.la_interval);
737                 RETURN(-EINVAL);
738         }
739
740         if (attr->u.delay.la_latency == 0) {
741                 CDEBUG(D_NET, "delay latency cannot be zero\n");
742                 RETURN(-EINVAL);
743         }
744
745         if (lnet_fault_attr_validate(attr) != 0)
746                 RETURN(-EINVAL);
747
748         CFS_ALLOC_PTR(rule);
749         if (rule == NULL)
750                 RETURN(-ENOMEM);
751
752         mutex_lock(&delay_dd.dd_mutex);
753         if (!delay_dd.dd_running) {
754                 struct task_struct *task;
755
756                 /* NB: although LND threads will process delayed message
757                  * in lnet_finalize, but there is no guarantee that LND
758                  * threads will be waken up if no other message needs to
759                  * be handled.
760                  * Only one daemon thread, performance is not the concern
761                  * of this simualation module.
762                  */
763                 task = kthread_run(lnet_delay_rule_daemon, NULL, "lnet_dd");
764                 if (IS_ERR(task)) {
765                         rc = PTR_ERR(task);
766                         GOTO(failed, rc);
767                 }
768                 wait_event(delay_dd.dd_ctl_waitq, delay_dd.dd_running);
769         }
770
771         init_timer(&rule->dl_timer);
772         rule->dl_timer.function = delay_timer_cb;
773         rule->dl_timer.data = (unsigned long)rule;
774
775         spin_lock_init(&rule->dl_lock);
776         INIT_LIST_HEAD(&rule->dl_msg_list);
777         INIT_LIST_HEAD(&rule->dl_sched_link);
778
779         rule->dl_attr = *attr;
780         if (attr->u.delay.la_interval != 0) {
781                 rule->dl_time_base = cfs_time_shift(attr->u.delay.la_interval);
782                 rule->dl_delay_time = cfs_time_shift(cfs_rand() %
783                                                      attr->u.delay.la_interval);
784         } else {
785                 rule->dl_delay_at = cfs_rand() % attr->u.delay.la_rate;
786         }
787
788         rule->dl_msg_send = -1;
789
790         lnet_net_lock(LNET_LOCK_EX);
791         atomic_set(&rule->dl_refcount, 1);
792         list_add(&rule->dl_link, &the_lnet.ln_delay_rules);
793         lnet_net_unlock(LNET_LOCK_EX);
794
795         CDEBUG(D_NET, "Added delay rule: src %s, dst %s, rate %d\n",
796                libcfs_nid2str(attr->fa_src), libcfs_nid2str(attr->fa_src),
797                attr->u.delay.la_rate);
798
799         mutex_unlock(&delay_dd.dd_mutex);
800         RETURN(0);
801  failed:
802         mutex_unlock(&delay_dd.dd_mutex);
803         CFS_FREE_PTR(rule);
804         return rc;
805 }
806
807 /**
808  * Remove matched Delay Rules from lnet, if \a shutdown is true or both \a src
809  * and \a dst are zero, all rules will be removed, otherwise only matched rules
810  * will be removed.
811  * If \a src is zero, then all rules have \a dst as destination will be remove
812  * If \a dst is zero, then all rules have \a src as source will be removed
813  *
814  * When a delay rule is removed, all delayed messages of this rule will be
815  * processed immediately.
816  */
817 int
818 lnet_delay_rule_del(lnet_nid_t src, lnet_nid_t dst, bool shutdown)
819 {
820         struct lnet_delay_rule *rule;
821         struct lnet_delay_rule  *tmp;
822         struct list_head        rule_list;
823         struct list_head        msg_list;
824         int                     n = 0;
825         bool                    cleanup;
826         ENTRY;
827
828         INIT_LIST_HEAD(&rule_list);
829         INIT_LIST_HEAD(&msg_list);
830
831         if (shutdown)
832                 src = dst = 0;
833
834         mutex_lock(&delay_dd.dd_mutex);
835         lnet_net_lock(LNET_LOCK_EX);
836
837         list_for_each_entry_safe(rule, tmp, &the_lnet.ln_delay_rules, dl_link) {
838                 if (rule->dl_attr.fa_src != src && src != 0)
839                         continue;
840
841                 if (rule->dl_attr.fa_dst != dst && dst != 0)
842                         continue;
843
844                 CDEBUG(D_NET, "Remove delay rule: src %s->dst: %s (1/%d, %d)\n",
845                        libcfs_nid2str(rule->dl_attr.fa_src),
846                        libcfs_nid2str(rule->dl_attr.fa_dst),
847                        rule->dl_attr.u.delay.la_rate,
848                        rule->dl_attr.u.delay.la_interval);
849                 /* refcount is taken over by rule_list */
850                 list_move(&rule->dl_link, &rule_list);
851         }
852
853         /* check if we need to shutdown delay_daemon */
854         cleanup = list_empty(&the_lnet.ln_delay_rules) &&
855                   !list_empty(&rule_list);
856         lnet_net_unlock(LNET_LOCK_EX);
857
858         list_for_each_entry_safe(rule, tmp, &rule_list, dl_link) {
859                 list_del_init(&rule->dl_link);
860
861                 del_timer_sync(&rule->dl_timer);
862                 delayed_msg_check(rule, true, &msg_list);
863                 delay_rule_decref(rule); /* -1 for the_lnet.ln_delay_rules */
864                 n++;
865         }
866
867         if (cleanup) { /* no more delay rule, shutdown delay_daemon */
868                 LASSERT(delay_dd.dd_running);
869                 delay_dd.dd_running = 0;
870                 wake_up(&delay_dd.dd_waitq);
871
872                 while (!delay_dd.dd_stopped)
873                         wait_event(delay_dd.dd_ctl_waitq, delay_dd.dd_stopped);
874         }
875         mutex_unlock(&delay_dd.dd_mutex);
876
877         if (!list_empty(&msg_list))
878                 delayed_msg_process(&msg_list, shutdown);
879
880         RETURN(n);
881 }
882
883 /**
884  * List Delay Rule at position of \a pos
885  */
886 int
887 lnet_delay_rule_list(int pos, struct lnet_fault_attr *attr,
888                     struct lnet_fault_stat *stat)
889 {
890         struct lnet_delay_rule *rule;
891         int                     cpt;
892         int                     i = 0;
893         int                     rc = -ENOENT;
894         ENTRY;
895
896         cpt = lnet_net_lock_current();
897         list_for_each_entry(rule, &the_lnet.ln_delay_rules, dl_link) {
898                 if (i++ < pos)
899                         continue;
900
901                 spin_lock(&rule->dl_lock);
902                 *attr = rule->dl_attr;
903                 *stat = rule->dl_stat;
904                 spin_unlock(&rule->dl_lock);
905                 rc = 0;
906                 break;
907         }
908
909         lnet_net_unlock(cpt);
910         RETURN(rc);
911 }
912
913 /**
914  * reset counters for all Delay Rules
915  */
916 void
917 lnet_delay_rule_reset(void)
918 {
919         struct lnet_delay_rule *rule;
920         int                     cpt;
921         ENTRY;
922
923         cpt = lnet_net_lock_current();
924
925         list_for_each_entry(rule, &the_lnet.ln_delay_rules, dl_link) {
926                 struct lnet_fault_attr *attr = &rule->dl_attr;
927
928                 spin_lock(&rule->dl_lock);
929
930                 memset(&rule->dl_stat, 0, sizeof(rule->dl_stat));
931                 if (attr->u.delay.la_rate != 0) {
932                         rule->dl_delay_at = cfs_rand() % attr->u.delay.la_rate;
933                 } else {
934                         rule->dl_delay_time = cfs_time_shift(cfs_rand() %
935                                                 attr->u.delay.la_interval);
936                         rule->dl_time_base = cfs_time_shift(attr->u.delay.
937                                                                   la_interval);
938                 }
939                 spin_unlock(&rule->dl_lock);
940         }
941
942         lnet_net_unlock(cpt);
943         EXIT;
944 }
945
946 int
947 lnet_fault_ctl(int opc, struct libcfs_ioctl_data *data)
948 {
949         struct lnet_fault_attr *attr;
950         struct lnet_fault_stat *stat;
951
952         attr = (struct lnet_fault_attr *)data->ioc_inlbuf1;
953
954         switch (opc) {
955         default:
956                 return -EINVAL;
957
958         case LNET_CTL_DROP_ADD:
959                 if (attr == NULL)
960                         return -EINVAL;
961
962                 return lnet_drop_rule_add(attr);
963
964         case LNET_CTL_DROP_DEL:
965                 if (attr == NULL)
966                         return -EINVAL;
967
968                 data->ioc_count = lnet_drop_rule_del(attr->fa_src,
969                                                      attr->fa_dst);
970                 return 0;
971
972         case LNET_CTL_DROP_RESET:
973                 lnet_drop_rule_reset();
974                 return 0;
975
976         case LNET_CTL_DROP_LIST:
977                 stat = (struct lnet_fault_stat *)data->ioc_inlbuf2;
978                 if (attr == NULL || stat == NULL)
979                         return -EINVAL;
980
981                 return lnet_drop_rule_list(data->ioc_count, attr, stat);
982
983         case LNET_CTL_DELAY_ADD:
984                 if (attr == NULL)
985                         return -EINVAL;
986
987                 return lnet_delay_rule_add(attr);
988
989         case LNET_CTL_DELAY_DEL:
990                 if (attr == NULL)
991                         return -EINVAL;
992
993                 data->ioc_count = lnet_delay_rule_del(attr->fa_src,
994                                                       attr->fa_dst, false);
995                 return 0;
996
997         case LNET_CTL_DELAY_RESET:
998                 lnet_delay_rule_reset();
999                 return 0;
1000
1001         case LNET_CTL_DELAY_LIST:
1002                 stat = (struct lnet_fault_stat *)data->ioc_inlbuf2;
1003                 if (attr == NULL || stat == NULL)
1004                         return -EINVAL;
1005
1006                 return lnet_delay_rule_list(data->ioc_count, attr, stat);
1007         }
1008 }
1009
1010 int
1011 lnet_fault_init(void)
1012 {
1013         CLASSERT(LNET_PUT_BIT == 1 << LNET_MSG_PUT);
1014         CLASSERT(LNET_ACK_BIT == 1 << LNET_MSG_ACK);
1015         CLASSERT(LNET_GET_BIT == 1 << LNET_MSG_GET);
1016         CLASSERT(LNET_REPLY_BIT == 1 << LNET_MSG_REPLY);
1017
1018         mutex_init(&delay_dd.dd_mutex);
1019         spin_lock_init(&delay_dd.dd_lock);
1020         init_waitqueue_head(&delay_dd.dd_waitq);
1021         init_waitqueue_head(&delay_dd.dd_ctl_waitq);
1022         INIT_LIST_HEAD(&delay_dd.dd_sched_rules);
1023
1024         return 0;
1025 }
1026
1027 void
1028 lnet_fault_fini(void)
1029 {
1030         lnet_drop_rule_del(0, 0);
1031         lnet_delay_rule_del(0, 0, true);
1032
1033         LASSERT(list_empty(&the_lnet.ln_drop_rules));
1034         LASSERT(list_empty(&the_lnet.ln_delay_rules));
1035         LASSERT(list_empty(&delay_dd.dd_sched_rules));
1036 }