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, 2017, 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 <uapi/linux/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         time64_t                dr_drop_time;
  61         /** baseline to caculate dr_drop_time */
  62         time64_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 = ktime_get_seconds() + attr->u.drop.da_interval;
 174                 rule->dr_drop_time = ktime_get_seconds() +
 175                                      cfs_rand() % 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 = ktime_get_seconds() +
 287                                              cfs_rand() % attr->u.drop.da_interval;
 288                         rule->dr_time_base = ktime_get_seconds() + attr->u.drop.da_interval;
 289                 }
 290                 spin_unlock(&rule->dr_lock);
 291         }
 292
 293         lnet_net_unlock(cpt);
 294         EXIT;
 295 }
 296
 297 /**
 298  * check source/destination NID, portal, message type and drop rate,
 299  * decide whether should drop this message or not
 300  */
 301 static bool
 302 drop_rule_match(struct lnet_drop_rule *rule, lnet_nid_t src,
 303                 lnet_nid_t dst, unsigned int type, unsigned int portal)
 304 {
 305         struct lnet_fault_attr  *attr = &rule->dr_attr;
 306         bool                     drop;
 307
 308         if (!lnet_fault_attr_match(attr, src, dst, type, portal))
 309                 return false;
 310
 311         /* match this rule, check drop rate now */
 312         spin_lock(&rule->dr_lock);
 313         if (rule->dr_drop_time != 0) { /* time based drop */
 314                 time64_t now = ktime_get_seconds();
 315
 316                 rule->dr_stat.fs_count++;
 317                 drop = now >= rule->dr_drop_time;
 318                 if (drop) {
 319                         if (now > rule->dr_time_base)
 320                                 rule->dr_time_base = now;
 321
 322                         rule->dr_drop_time = rule->dr_time_base +
 323                                              cfs_rand() % attr->u.drop.da_interval;
 324                         rule->dr_time_base += attr->u.drop.da_interval;
 325
 326                         CDEBUG(D_NET, "Drop Rule %s->%s: next drop : %lld\n",
 327                                libcfs_nid2str(attr->fa_src),
 328                                libcfs_nid2str(attr->fa_dst),
 329                                rule->dr_drop_time);
 330                 }
 331
 332         } else { /* rate based drop */
 333                 __u64 count;
 334
 335                 drop = rule->dr_stat.fs_count++ == rule->dr_drop_at;
 336                 count = rule->dr_stat.fs_count;
 337                 if (do_div(count, attr->u.drop.da_rate) == 0) {
 338                         rule->dr_drop_at = rule->dr_stat.fs_count +
 339                                            cfs_rand() % attr->u.drop.da_rate;
 340                         CDEBUG(D_NET, "Drop Rule %s->%s: next drop: %lu\n",
 341                                libcfs_nid2str(attr->fa_src),
 342                                libcfs_nid2str(attr->fa_dst), rule->dr_drop_at);
 343                 }
 344         }
 345
 346         if (drop) { /* drop this message, update counters */
 347                 lnet_fault_stat_inc(&rule->dr_stat, type);
 348                 rule->dr_stat.u.drop.ds_dropped++;
 349         }
 350
 351         spin_unlock(&rule->dr_lock);
 352         return drop;
 353 }
 354
 355 /**
 356  * Check if message from \a src to \a dst can match any existed drop rule
 357  */
 358 bool
 359 lnet_drop_rule_match(struct lnet_hdr *hdr)
 360 {
 361         struct lnet_drop_rule   *rule;
 362         lnet_nid_t               src = le64_to_cpu(hdr->src_nid);
 363         lnet_nid_t               dst = le64_to_cpu(hdr->dest_nid);
 364         unsigned int             typ = le32_to_cpu(hdr->type);
 365         unsigned int             ptl = -1;
 366         bool                     drop = false;
 367         int                      cpt;
 368
 369         /* NB: if Portal is specified, then only PUT and GET will be
 370          * filtered by drop rule */
 371         if (typ == LNET_MSG_PUT)
 372                 ptl = le32_to_cpu(hdr->msg.put.ptl_index);
 373         else if (typ == LNET_MSG_GET)
 374                 ptl = le32_to_cpu(hdr->msg.get.ptl_index);
 375
 376         cpt = lnet_net_lock_current();
 377         list_for_each_entry(rule, &the_lnet.ln_drop_rules, dr_link) {
 378                 drop = drop_rule_match(rule, src, dst, typ, ptl);
 379                 if (drop)
 380                         break;
 381         }
 382
 383         lnet_net_unlock(cpt);
 384         return drop;
 385 }
 386
 387 /**
 388  * LNet Delay Simulation
 389  */
 390 /** timestamp (second) to send delayed message */
 391 #define msg_delay_send           msg_ev.hdr_data
 392
 393 struct lnet_delay_rule {
 394         /** link chain on the_lnet.ln_delay_rules */
 395         struct list_head        dl_link;
 396         /** link chain on delay_dd.dd_sched_rules */
 397         struct list_head        dl_sched_link;
 398         /** attributes of this rule */
 399         struct lnet_fault_attr  dl_attr;
 400         /** lock to protect \a below members */
 401         spinlock_t              dl_lock;
 402         /** refcount of delay rule */
 403         atomic_t                dl_refcount;
 404         /**
 405          * the message sequence to delay, which means message is delayed when
 406          * dl_stat.fs_count == dl_delay_at
 407          */
 408         unsigned long           dl_delay_at;
 409         /**
 410          * seconds to delay the next message, it's exclusive with dl_delay_at
 411          */
 412         time64_t                dl_delay_time;
 413         /** baseline to caculate dl_delay_time */
 414         time64_t                dl_time_base;
 415         /** jiffies to send the next delayed message */
 416         unsigned long           dl_msg_send;
 417         /** delayed message list */
 418         struct list_head        dl_msg_list;
 419         /** statistic of delayed messages */
 420         struct lnet_fault_stat  dl_stat;
 421         /** timer to wakeup delay_daemon */
 422         struct timer_list       dl_timer;
 423 };
 424
 425 struct delay_daemon_data {
 426         /** serialise rule add/remove */
 427         struct mutex            dd_mutex;
 428         /** protect rules on \a dd_sched_rules */
 429         spinlock_t              dd_lock;
 430         /** scheduled delay rules (by timer) */
 431         struct list_head        dd_sched_rules;
 432         /** deamon thread sleeps at here */
 433         wait_queue_head_t       dd_waitq;
 434         /** controler (lctl command) wait at here */
 435         wait_queue_head_t       dd_ctl_waitq;
 436         /** deamon is running */
 437         unsigned int            dd_running;
 438         /** deamon stopped */
 439         unsigned int            dd_stopped;
 440 };
 441
 442 static struct delay_daemon_data delay_dd;
 443
 444 static void
 445 delay_rule_decref(struct lnet_delay_rule *rule)
 446 {
 447         if (atomic_dec_and_test(&rule->dl_refcount)) {
 448                 LASSERT(list_empty(&rule->dl_sched_link));
 449                 LASSERT(list_empty(&rule->dl_msg_list));
 450                 LASSERT(list_empty(&rule->dl_link));
 451
 452                 CFS_FREE_PTR(rule);
 453         }
 454 }
 455
 456 /**
 457  * check source/destination NID, portal, message type and delay rate,
 458  * decide whether should delay this message or not
 459  */
 460 static bool
 461 delay_rule_match(struct lnet_delay_rule *rule, lnet_nid_t src,
 462                 lnet_nid_t dst, unsigned int type, unsigned int portal,
 463                 struct lnet_msg *msg)
 464 {
 465         struct lnet_fault_attr  *attr = &rule->dl_attr;
 466         bool                     delay;
 467
 468         if (!lnet_fault_attr_match(attr, src, dst, type, portal))
 469                 return false;
 470
 471         /* match this rule, check delay rate now */
 472         spin_lock(&rule->dl_lock);
 473         if (rule->dl_delay_time != 0) { /* time based delay */
 474                 time64_t now = ktime_get_seconds();
 475
 476                 rule->dl_stat.fs_count++;
 477                 delay = now >= rule->dl_delay_time;
 478                 if (delay) {
 479                         if (now > rule->dl_time_base)
 480                                 rule->dl_time_base = now;
 481
 482                         rule->dl_delay_time = rule->dl_time_base +
 483                                               cfs_rand() % attr->u.delay.la_interval;
 484                         rule->dl_time_base += attr->u.delay.la_interval;
 485
 486                         CDEBUG(D_NET, "Delay Rule %s->%s: next delay : %lld\n",
 487                                libcfs_nid2str(attr->fa_src),
 488                                libcfs_nid2str(attr->fa_dst),
 489                                rule->dl_delay_time);
 490                 }
 491
 492         } else { /* rate based delay */
 493                 __u64 count;
 494
 495                 delay = rule->dl_stat.fs_count++ == rule->dl_delay_at;
 496                 /* generate the next random rate sequence */
 497                 count = rule->dl_stat.fs_count;
 498                 if (do_div(count, attr->u.delay.la_rate) == 0) {
 499                         rule->dl_delay_at = rule->dl_stat.fs_count +
 500                                             cfs_rand() % attr->u.delay.la_rate;
 501                         CDEBUG(D_NET, "Delay Rule %s->%s: next delay: %lu\n",
 502                                libcfs_nid2str(attr->fa_src),
 503                                libcfs_nid2str(attr->fa_dst), rule->dl_delay_at);
 504                 }
 505         }
 506
 507         if (!delay) {
 508                 spin_unlock(&rule->dl_lock);
 509                 return false;
 510         }
 511
 512         /* delay this message, update counters */
 513         lnet_fault_stat_inc(&rule->dl_stat, type);
 514         rule->dl_stat.u.delay.ls_delayed++;
 515
 516         list_add_tail(&msg->msg_list, &rule->dl_msg_list);
 517         msg->msg_delay_send = ktime_get_seconds() + attr->u.delay.la_latency;
 518         if (rule->dl_msg_send == -1) {
 519                 rule->dl_msg_send = msg->msg_delay_send;
 520                 mod_timer(&rule->dl_timer, rule->dl_msg_send);
 521         }
 522
 523         spin_unlock(&rule->dl_lock);
 524         return true;
 525 }
 526
 527 /**
 528  * check if \a msg can match any Delay Rule, receiving of this message
 529  * will be delayed if there is a match.
 530  */
 531 bool
 532 lnet_delay_rule_match_locked(struct lnet_hdr *hdr, struct lnet_msg *msg)
 533 {
 534         struct lnet_delay_rule  *rule;
 535         lnet_nid_t               src = le64_to_cpu(hdr->src_nid);
 536         lnet_nid_t               dst = le64_to_cpu(hdr->dest_nid);
 537         unsigned int             typ = le32_to_cpu(hdr->type);
 538         unsigned int             ptl = -1;
 539
 540         /* NB: called with hold of lnet_net_lock */
 541
 542         /* NB: if Portal is specified, then only PUT and GET will be
 543          * filtered by delay rule */
 544         if (typ == LNET_MSG_PUT)
 545                 ptl = le32_to_cpu(hdr->msg.put.ptl_index);
 546         else if (typ == LNET_MSG_GET)
 547                 ptl = le32_to_cpu(hdr->msg.get.ptl_index);
 548
 549         list_for_each_entry(rule, &the_lnet.ln_delay_rules, dl_link) {
 550                 if (delay_rule_match(rule, src, dst, typ, ptl, msg))
 551                         return true;
 552         }
 553
 554         return false;
 555 }
 556
 557 /** check out delayed messages for send */
 558 static void
 559 delayed_msg_check(struct lnet_delay_rule *rule, bool all,
 560                   struct list_head *msg_list)
 561 {
 562         struct lnet_msg *msg;
 563         struct lnet_msg *tmp;
 564         time64_t now = ktime_get_seconds();
 565
 566         if (!all && cfs_time_seconds(rule->dl_msg_send) > now)
 567                 return;
 568
 569         spin_lock(&rule->dl_lock);
 570         list_for_each_entry_safe(msg, tmp, &rule->dl_msg_list, msg_list) {
 571                 if (!all && msg->msg_delay_send > now)
 572                         break;
 573
 574                 msg->msg_delay_send = 0;
 575                 list_move_tail(&msg->msg_list, msg_list);
 576         }
 577
 578         if (list_empty(&rule->dl_msg_list)) {
 579                 del_timer(&rule->dl_timer);
 580                 rule->dl_msg_send = -1;
 581
 582         } else if (!list_empty(msg_list)) {
 583                 /* dequeued some timedout messages, update timer for the
 584                  * next delayed message on rule */
 585                 msg = list_entry(rule->dl_msg_list.next,
 586                                  struct lnet_msg, msg_list);
 587                 rule->dl_msg_send = msg->msg_delay_send;
 588                 mod_timer(&rule->dl_timer, rule->dl_msg_send);
 589         }
 590         spin_unlock(&rule->dl_lock);
 591 }
 592
 593 static void
 594 delayed_msg_process(struct list_head *msg_list, bool drop)
 595 {
 596         struct lnet_msg *msg;
 597
 598         while (!list_empty(msg_list)) {
 599                 struct lnet_ni *ni;
 600                 int             cpt;
 601                 int             rc;
 602
 603                 msg = list_entry(msg_list->next, struct lnet_msg, msg_list);
 604                 LASSERT(msg->msg_rxpeer != NULL);
 605                 LASSERT(msg->msg_rxni != NULL);
 606
 607                 ni = msg->msg_rxni;
 608                 cpt = msg->msg_rx_cpt;
 609
 610                 list_del_init(&msg->msg_list);
 611                 if (drop) {
 612                         rc = -ECANCELED;
 613
 614                 } else if (!msg->msg_routing) {
 615                         rc = lnet_parse_local(ni, msg);
 616                         if (rc == 0)
 617                                 continue;
 618
 619                 } else {
 620                         lnet_net_lock(cpt);
 621                         rc = lnet_parse_forward_locked(ni, msg);
 622                         lnet_net_unlock(cpt);
 623
 624                         switch (rc) {
 625                         case LNET_CREDIT_OK:
 626                                 lnet_ni_recv(ni, msg->msg_private, msg, 0,
 627                                              0, msg->msg_len, msg->msg_len);
 628                         case LNET_CREDIT_WAIT:
 629                                 continue;
 630                         default: /* failures */
 631                                 break;
 632                         }
 633                 }
 634
 635                 lnet_drop_message(ni, cpt, msg->msg_private, msg->msg_len,
 636                                   msg->msg_type);
 637                 lnet_finalize(msg, rc);
 638         }
 639 }
 640
 641 /**
 642  * Process delayed messages for scheduled rules
 643  * This function can either be called by delay_rule_daemon, or by lnet_finalise
 644  */
 645 void
 646 lnet_delay_rule_check(void)
 647 {
 648         struct lnet_delay_rule  *rule;
 649         struct list_head         msgs;
 650
 651         INIT_LIST_HEAD(&msgs);
 652         while (1) {
 653                 if (list_empty(&delay_dd.dd_sched_rules))
 654                         break;
 655
 656                 spin_lock_bh(&delay_dd.dd_lock);
 657                 if (list_empty(&delay_dd.dd_sched_rules)) {
 658                         spin_unlock_bh(&delay_dd.dd_lock);
 659                         break;
 660                 }
 661
 662                 rule = list_entry(delay_dd.dd_sched_rules.next,
 663                                   struct lnet_delay_rule, dl_sched_link);
 664                 list_del_init(&rule->dl_sched_link);
 665                 spin_unlock_bh(&delay_dd.dd_lock);
 666
 667                 delayed_msg_check(rule, false, &msgs);
 668                 delay_rule_decref(rule); /* -1 for delay_dd.dd_sched_rules */
 669         }
 670
 671         if (!list_empty(&msgs))
 672                 delayed_msg_process(&msgs, false);
 673 }
 674
 675 /** deamon thread to handle delayed messages */
 676 static int
 677 lnet_delay_rule_daemon(void *arg)
 678 {
 679         delay_dd.dd_running = 1;
 680         wake_up(&delay_dd.dd_ctl_waitq);
 681
 682         while (delay_dd.dd_running) {
 683                 wait_event_interruptible(delay_dd.dd_waitq,
 684                                          !delay_dd.dd_running ||
 685                                          !list_empty(&delay_dd.dd_sched_rules));
 686                 lnet_delay_rule_check();
 687         }
 688
 689         /* in case more rules have been enqueued after my last check */
 690         lnet_delay_rule_check();
 691         delay_dd.dd_stopped = 1;
 692         wake_up(&delay_dd.dd_ctl_waitq);
 693
 694         return 0;
 695 }
 696
 697 static void
 698 delay_timer_cb(unsigned long arg)
 699 {
 700         struct lnet_delay_rule *rule = (struct lnet_delay_rule *)arg;
 701
 702         spin_lock_bh(&delay_dd.dd_lock);
 703         if (list_empty(&rule->dl_sched_link) && delay_dd.dd_running) {
 704                 atomic_inc(&rule->dl_refcount);
 705                 list_add_tail(&rule->dl_sched_link, &delay_dd.dd_sched_rules);
 706                 wake_up(&delay_dd.dd_waitq);
 707         }
 708         spin_unlock_bh(&delay_dd.dd_lock);
 709 }
 710
 711 /**
 712  * Add a new delay rule to LNet
 713  * There is no check for duplicated delay rule, all rules will be checked for
 714  * incoming message.
 715  */
 716 int
 717 lnet_delay_rule_add(struct lnet_fault_attr *attr)
 718 {
 719         struct lnet_delay_rule *rule;
 720         int                     rc = 0;
 721         ENTRY;
 722
 723         if (!((attr->u.delay.la_rate == 0) ^
 724               (attr->u.delay.la_interval == 0))) {
 725                 CDEBUG(D_NET,
 726                        "please provide either delay rate or delay interval, "
 727                        "but not both at the same time %d/%d\n",
 728                        attr->u.delay.la_rate, attr->u.delay.la_interval);
 729                 RETURN(-EINVAL);
 730         }
 731
 732         if (attr->u.delay.la_latency == 0) {
 733                 CDEBUG(D_NET, "delay latency cannot be zero\n");
 734                 RETURN(-EINVAL);
 735         }
 736
 737         if (lnet_fault_attr_validate(attr) != 0)
 738                 RETURN(-EINVAL);
 739
 740         CFS_ALLOC_PTR(rule);
 741         if (rule == NULL)
 742                 RETURN(-ENOMEM);
 743
 744         mutex_lock(&delay_dd.dd_mutex);
 745         if (!delay_dd.dd_running) {
 746                 struct task_struct *task;
 747
 748                 /* NB: although LND threads will process delayed message
 749                  * in lnet_finalize, but there is no guarantee that LND
 750                  * threads will be waken up if no other message needs to
 751                  * be handled.
 752                  * Only one daemon thread, performance is not the concern
 753                  * of this simualation module.
 754                  */
 755                 task = kthread_run(lnet_delay_rule_daemon, NULL, "lnet_dd");
 756                 if (IS_ERR(task)) {
 757                         rc = PTR_ERR(task);
 758                         GOTO(failed, rc);
 759                 }
 760                 wait_event(delay_dd.dd_ctl_waitq, delay_dd.dd_running);
 761         }
 762
 763         init_timer(&rule->dl_timer);
 764         rule->dl_timer.function = delay_timer_cb;
 765         rule->dl_timer.data = (unsigned long)rule;
 766
 767         spin_lock_init(&rule->dl_lock);
 768         INIT_LIST_HEAD(&rule->dl_msg_list);
 769         INIT_LIST_HEAD(&rule->dl_sched_link);
 770
 771         rule->dl_attr = *attr;
 772         if (attr->u.delay.la_interval != 0) {
 773                 rule->dl_time_base = ktime_get_seconds() +
 774                                      attr->u.delay.la_interval;
 775                 rule->dl_delay_time = ktime_get_seconds() +
 776                                       cfs_rand() % attr->u.delay.la_interval;
 777         } else {
 778                 rule->dl_delay_at = cfs_rand() % attr->u.delay.la_rate;
 779         }
 780
 781         rule->dl_msg_send = -1;
 782
 783         lnet_net_lock(LNET_LOCK_EX);
 784         atomic_set(&rule->dl_refcount, 1);
 785         list_add(&rule->dl_link, &the_lnet.ln_delay_rules);
 786         lnet_net_unlock(LNET_LOCK_EX);
 787
 788         CDEBUG(D_NET, "Added delay rule: src %s, dst %s, rate %d\n",
 789                libcfs_nid2str(attr->fa_src), libcfs_nid2str(attr->fa_src),
 790                attr->u.delay.la_rate);
 791
 792         mutex_unlock(&delay_dd.dd_mutex);
 793         RETURN(0);
 794  failed:
 795         mutex_unlock(&delay_dd.dd_mutex);
 796         CFS_FREE_PTR(rule);
 797         return rc;
 798 }
 799
 800 /**
 801  * Remove matched Delay Rules from lnet, if \a shutdown is true or both \a src
 802  * and \a dst are zero, all rules will be removed, otherwise only matched rules
 803  * will be removed.
 804  * If \a src is zero, then all rules have \a dst as destination will be remove
 805  * If \a dst is zero, then all rules have \a src as source will be removed
 806  *
 807  * When a delay rule is removed, all delayed messages of this rule will be
 808  * processed immediately.
 809  */
 810 int
 811 lnet_delay_rule_del(lnet_nid_t src, lnet_nid_t dst, bool shutdown)
 812 {
 813         struct lnet_delay_rule *rule;
 814         struct lnet_delay_rule  *tmp;
 815         struct list_head        rule_list;
 816         struct list_head        msg_list;
 817         int                     n = 0;
 818         bool                    cleanup;
 819         ENTRY;
 820
 821         INIT_LIST_HEAD(&rule_list);
 822         INIT_LIST_HEAD(&msg_list);
 823
 824         if (shutdown)
 825                 src = dst = 0;
 826
 827         mutex_lock(&delay_dd.dd_mutex);
 828         lnet_net_lock(LNET_LOCK_EX);
 829
 830         list_for_each_entry_safe(rule, tmp, &the_lnet.ln_delay_rules, dl_link) {
 831                 if (rule->dl_attr.fa_src != src && src != 0)
 832                         continue;
 833
 834                 if (rule->dl_attr.fa_dst != dst && dst != 0)
 835                         continue;
 836
 837                 CDEBUG(D_NET, "Remove delay rule: src %s->dst: %s (1/%d, %d)\n",
 838                        libcfs_nid2str(rule->dl_attr.fa_src),
 839                        libcfs_nid2str(rule->dl_attr.fa_dst),
 840                        rule->dl_attr.u.delay.la_rate,
 841                        rule->dl_attr.u.delay.la_interval);
 842                 /* refcount is taken over by rule_list */
 843                 list_move(&rule->dl_link, &rule_list);
 844         }
 845
 846         /* check if we need to shutdown delay_daemon */
 847         cleanup = list_empty(&the_lnet.ln_delay_rules) &&
 848                   !list_empty(&rule_list);
 849         lnet_net_unlock(LNET_LOCK_EX);
 850
 851         list_for_each_entry_safe(rule, tmp, &rule_list, dl_link) {
 852                 list_del_init(&rule->dl_link);
 853
 854                 del_timer_sync(&rule->dl_timer);
 855                 delayed_msg_check(rule, true, &msg_list);
 856                 delay_rule_decref(rule); /* -1 for the_lnet.ln_delay_rules */
 857                 n++;
 858         }
 859
 860         if (cleanup) { /* no more delay rule, shutdown delay_daemon */
 861                 LASSERT(delay_dd.dd_running);
 862                 delay_dd.dd_running = 0;
 863                 wake_up(&delay_dd.dd_waitq);
 864
 865                 while (!delay_dd.dd_stopped)
 866                         wait_event(delay_dd.dd_ctl_waitq, delay_dd.dd_stopped);
 867         }
 868         mutex_unlock(&delay_dd.dd_mutex);
 869
 870         if (!list_empty(&msg_list))
 871                 delayed_msg_process(&msg_list, shutdown);
 872
 873         RETURN(n);
 874 }
 875
 876 /**
 877  * List Delay Rule at position of \a pos
 878  */
 879 int
 880 lnet_delay_rule_list(int pos, struct lnet_fault_attr *attr,
 881                     struct lnet_fault_stat *stat)
 882 {
 883         struct lnet_delay_rule *rule;
 884         int                     cpt;
 885         int                     i = 0;
 886         int                     rc = -ENOENT;
 887         ENTRY;
 888
 889         cpt = lnet_net_lock_current();
 890         list_for_each_entry(rule, &the_lnet.ln_delay_rules, dl_link) {
 891                 if (i++ < pos)
 892                         continue;
 893
 894                 spin_lock(&rule->dl_lock);
 895                 *attr = rule->dl_attr;
 896                 *stat = rule->dl_stat;
 897                 spin_unlock(&rule->dl_lock);
 898                 rc = 0;
 899                 break;
 900         }
 901
 902         lnet_net_unlock(cpt);
 903         RETURN(rc);
 904 }
 905
 906 /**
 907  * reset counters for all Delay Rules
 908  */
 909 void
 910 lnet_delay_rule_reset(void)
 911 {
 912         struct lnet_delay_rule *rule;
 913         int                     cpt;
 914         ENTRY;
 915
 916         cpt = lnet_net_lock_current();
 917
 918         list_for_each_entry(rule, &the_lnet.ln_delay_rules, dl_link) {
 919                 struct lnet_fault_attr *attr = &rule->dl_attr;
 920
 921                 spin_lock(&rule->dl_lock);
 922
 923                 memset(&rule->dl_stat, 0, sizeof(rule->dl_stat));
 924                 if (attr->u.delay.la_rate != 0) {
 925                         rule->dl_delay_at = cfs_rand() % attr->u.delay.la_rate;
 926                 } else {
 927                         rule->dl_delay_time = ktime_get_seconds() +
 928                                               cfs_rand() % attr->u.delay.la_interval;
 929                         rule->dl_time_base = ktime_get_seconds() +
 930                                              attr->u.delay.la_interval;
 931                 }
 932                 spin_unlock(&rule->dl_lock);
 933         }
 934
 935         lnet_net_unlock(cpt);
 936         EXIT;
 937 }
 938
 939 int
 940 lnet_fault_ctl(int opc, struct libcfs_ioctl_data *data)
 941 {
 942         struct lnet_fault_attr *attr;
 943         struct lnet_fault_stat *stat;
 944
 945         attr = (struct lnet_fault_attr *)data->ioc_inlbuf1;
 946
 947         switch (opc) {
 948         default:
 949                 return -EINVAL;
 950
 951         case LNET_CTL_DROP_ADD:
 952                 if (attr == NULL)
 953                         return -EINVAL;
 954
 955                 return lnet_drop_rule_add(attr);
 956
 957         case LNET_CTL_DROP_DEL:
 958                 if (attr == NULL)
 959                         return -EINVAL;
 960
 961                 data->ioc_count = lnet_drop_rule_del(attr->fa_src,
 962                                                      attr->fa_dst);
 963                 return 0;
 964
 965         case LNET_CTL_DROP_RESET:
 966                 lnet_drop_rule_reset();
 967                 return 0;
 968
 969         case LNET_CTL_DROP_LIST:
 970                 stat = (struct lnet_fault_stat *)data->ioc_inlbuf2;
 971                 if (attr == NULL || stat == NULL)
 972                         return -EINVAL;
 973
 974                 return lnet_drop_rule_list(data->ioc_count, attr, stat);
 975
 976         case LNET_CTL_DELAY_ADD:
 977                 if (attr == NULL)
 978                         return -EINVAL;
 979
 980                 return lnet_delay_rule_add(attr);
 981
 982         case LNET_CTL_DELAY_DEL:
 983                 if (attr == NULL)
 984                         return -EINVAL;
 985
 986                 data->ioc_count = lnet_delay_rule_del(attr->fa_src,
 987                                                       attr->fa_dst, false);
 988                 return 0;
 989
 990         case LNET_CTL_DELAY_RESET:
 991                 lnet_delay_rule_reset();
 992                 return 0;
 993
 994         case LNET_CTL_DELAY_LIST:
 995                 stat = (struct lnet_fault_stat *)data->ioc_inlbuf2;
 996                 if (attr == NULL || stat == NULL)
 997                         return -EINVAL;
 998
 999                 return lnet_delay_rule_list(data->ioc_count, attr, stat);
1000         }
1001 }
1002
1003 int
1004 lnet_fault_init(void)
1005 {
1006         CLASSERT(LNET_PUT_BIT == 1 << LNET_MSG_PUT);
1007         CLASSERT(LNET_ACK_BIT == 1 << LNET_MSG_ACK);
1008         CLASSERT(LNET_GET_BIT == 1 << LNET_MSG_GET);
1009         CLASSERT(LNET_REPLY_BIT == 1 << LNET_MSG_REPLY);
1010
1011         mutex_init(&delay_dd.dd_mutex);
1012         spin_lock_init(&delay_dd.dd_lock);
1013         init_waitqueue_head(&delay_dd.dd_waitq);
1014         init_waitqueue_head(&delay_dd.dd_ctl_waitq);
1015         INIT_LIST_HEAD(&delay_dd.dd_sched_rules);
1016
1017         return 0;
1018 }
1019
1020 void
1021 lnet_fault_fini(void)
1022 {
1023         lnet_drop_rule_del(0, 0);
1024         lnet_delay_rule_del(0, 0, true);
1025
1026         LASSERT(list_empty(&the_lnet.ln_drop_rules));
1027         LASSERT(list_empty(&the_lnet.ln_delay_rules));
1028         LASSERT(list_empty(&delay_dd.dd_sched_rules));
1029 }