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, 2016, 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 : %ld\n",
 330                                libcfs_nid2str(attr->fa_src),
 331                                libcfs_nid2str(attr->fa_dst),
 332                                rule->dr_drop_time);
 333                 }
 334
 335         } else { /* rate based drop */
 336                 __u64 count;
 337
 338                 drop = rule->dr_stat.fs_count++ == rule->dr_drop_at;
 339                 count = rule->dr_stat.fs_count;
 340                 if (do_div(count, attr->u.drop.da_rate) == 0) {
 341                         rule->dr_drop_at = rule->dr_stat.fs_count +
 342                                            cfs_rand() % attr->u.drop.da_rate;
 343                         CDEBUG(D_NET, "Drop Rule %s->%s: next drop: %lu\n",
 344                                libcfs_nid2str(attr->fa_src),
 345                                libcfs_nid2str(attr->fa_dst), rule->dr_drop_at);
 346                 }
 347         }
 348
 349         if (drop) { /* drop this message, update counters */
 350                 lnet_fault_stat_inc(&rule->dr_stat, type);
 351                 rule->dr_stat.u.drop.ds_dropped++;
 352         }
 353
 354         spin_unlock(&rule->dr_lock);
 355         return drop;
 356 }
 357
 358 /**
 359  * Check if message from \a src to \a dst can match any existed drop rule
 360  */
 361 bool
 362 lnet_drop_rule_match(struct lnet_hdr *hdr)
 363 {
 364         struct lnet_drop_rule   *rule;
 365         lnet_nid_t               src = le64_to_cpu(hdr->src_nid);
 366         lnet_nid_t               dst = le64_to_cpu(hdr->dest_nid);
 367         unsigned int             typ = le32_to_cpu(hdr->type);
 368         unsigned int             ptl = -1;
 369         bool                     drop = false;
 370         int                      cpt;
 371
 372         /* NB: if Portal is specified, then only PUT and GET will be
 373          * filtered by drop rule */
 374         if (typ == LNET_MSG_PUT)
 375                 ptl = le32_to_cpu(hdr->msg.put.ptl_index);
 376         else if (typ == LNET_MSG_GET)
 377                 ptl = le32_to_cpu(hdr->msg.get.ptl_index);
 378
 379         cpt = lnet_net_lock_current();
 380         list_for_each_entry(rule, &the_lnet.ln_drop_rules, dr_link) {
 381                 drop = drop_rule_match(rule, src, dst, typ, ptl);
 382                 if (drop)
 383                         break;
 384         }
 385
 386         lnet_net_unlock(cpt);
 387         return drop;
 388 }
 389
 390 /**
 391  * LNet Delay Simulation
 392  */
 393 /** timestamp (second) to send delayed message */
 394 #define msg_delay_send           msg_ev.hdr_data
 395
 396 struct lnet_delay_rule {
 397         /** link chain on the_lnet.ln_delay_rules */
 398         struct list_head        dl_link;
 399         /** link chain on delay_dd.dd_sched_rules */
 400         struct list_head        dl_sched_link;
 401         /** attributes of this rule */
 402         struct lnet_fault_attr  dl_attr;
 403         /** lock to protect \a below members */
 404         spinlock_t              dl_lock;
 405         /** refcount of delay rule */
 406         atomic_t                dl_refcount;
 407         /**
 408          * the message sequence to delay, which means message is delayed when
 409          * dl_stat.fs_count == dl_delay_at
 410          */
 411         unsigned long           dl_delay_at;
 412         /**
 413          * seconds to delay the next message, it's exclusive with dl_delay_at
 414          */
 415         cfs_time_t              dl_delay_time;
 416         /** baseline to caculate dl_delay_time */
 417         cfs_time_t              dl_time_base;
 418         /** jiffies to send the next delayed message */
 419         unsigned long           dl_msg_send;
 420         /** delayed message list */
 421         struct list_head        dl_msg_list;
 422         /** statistic of delayed messages */
 423         struct lnet_fault_stat  dl_stat;
 424         /** timer to wakeup delay_daemon */
 425         struct timer_list       dl_timer;
 426 };
 427
 428 struct delay_daemon_data {
 429         /** serialise rule add/remove */
 430         struct mutex            dd_mutex;
 431         /** protect rules on \a dd_sched_rules */
 432         spinlock_t              dd_lock;
 433         /** scheduled delay rules (by timer) */
 434         struct list_head        dd_sched_rules;
 435         /** deamon thread sleeps at here */
 436         wait_queue_head_t       dd_waitq;
 437         /** controler (lctl command) wait at here */
 438         wait_queue_head_t       dd_ctl_waitq;
 439         /** deamon is running */
 440         unsigned int            dd_running;
 441         /** deamon stopped */
 442         unsigned int            dd_stopped;
 443 };
 444
 445 static struct delay_daemon_data delay_dd;
 446
 447 static cfs_time_t
 448 round_timeout(cfs_time_t timeout)
 449 {
 450         return cfs_time_seconds((unsigned int)
 451                         cfs_duration_sec(cfs_time_sub(timeout, 0)) + 1);
 452 }
 453
 454 static void
 455 delay_rule_decref(struct lnet_delay_rule *rule)
 456 {
 457         if (atomic_dec_and_test(&rule->dl_refcount)) {
 458                 LASSERT(list_empty(&rule->dl_sched_link));
 459                 LASSERT(list_empty(&rule->dl_msg_list));
 460                 LASSERT(list_empty(&rule->dl_link));
 461
 462                 CFS_FREE_PTR(rule);
 463         }
 464 }
 465
 466 /**
 467  * check source/destination NID, portal, message type and delay rate,
 468  * decide whether should delay this message or not
 469  */
 470 static bool
 471 delay_rule_match(struct lnet_delay_rule *rule, lnet_nid_t src,
 472                 lnet_nid_t dst, unsigned int type, unsigned int portal,
 473                 struct lnet_msg *msg)
 474 {
 475         struct lnet_fault_attr  *attr = &rule->dl_attr;
 476         bool                     delay;
 477
 478         if (!lnet_fault_attr_match(attr, src, dst, type, portal))
 479                 return false;
 480
 481         /* match this rule, check delay rate now */
 482         spin_lock(&rule->dl_lock);
 483         if (rule->dl_delay_time != 0) { /* time based delay */
 484                 cfs_time_t now = cfs_time_current();
 485
 486                 rule->dl_stat.fs_count++;
 487                 delay = cfs_time_aftereq(now, rule->dl_delay_time);
 488                 if (delay) {
 489                         if (cfs_time_after(now, rule->dl_time_base))
 490                                 rule->dl_time_base = now;
 491
 492                         rule->dl_delay_time = rule->dl_time_base +
 493                                              cfs_time_seconds(cfs_rand() %
 494                                                 attr->u.delay.la_interval);
 495                         rule->dl_time_base += cfs_time_seconds(attr->u.delay.
 496                                                                la_interval);
 497
 498                         CDEBUG(D_NET, "Delay Rule %s->%s: next delay : %ld\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                 __u64 count;
 506
 507                 delay = rule->dl_stat.fs_count++ == rule->dl_delay_at;
 508                 /* generate the next random rate sequence */
 509                 count = rule->dl_stat.fs_count;
 510                 if (do_div(count, attr->u.delay.la_rate) == 0) {
 511                         rule->dl_delay_at = rule->dl_stat.fs_count +
 512                                             cfs_rand() % attr->u.delay.la_rate;
 513                         CDEBUG(D_NET, "Delay Rule %s->%s: next delay: %lu\n",
 514                                libcfs_nid2str(attr->fa_src),
 515                                libcfs_nid2str(attr->fa_dst), rule->dl_delay_at);
 516                 }
 517         }
 518
 519         if (!delay) {
 520                 spin_unlock(&rule->dl_lock);
 521                 return false;
 522         }
 523
 524         /* delay this message, update counters */
 525         lnet_fault_stat_inc(&rule->dl_stat, type);
 526         rule->dl_stat.u.delay.ls_delayed++;
 527
 528         list_add_tail(&msg->msg_list, &rule->dl_msg_list);
 529         msg->msg_delay_send = round_timeout(
 530                         cfs_time_shift(attr->u.delay.la_latency));
 531         if (rule->dl_msg_send == -1) {
 532                 rule->dl_msg_send = msg->msg_delay_send;
 533                 mod_timer(&rule->dl_timer, rule->dl_msg_send);
 534         }
 535
 536         spin_unlock(&rule->dl_lock);
 537         return true;
 538 }
 539
 540 /**
 541  * check if \a msg can match any Delay Rule, receiving of this message
 542  * will be delayed if there is a match.
 543  */
 544 bool
 545 lnet_delay_rule_match_locked(struct lnet_hdr *hdr, struct lnet_msg *msg)
 546 {
 547         struct lnet_delay_rule  *rule;
 548         lnet_nid_t               src = le64_to_cpu(hdr->src_nid);
 549         lnet_nid_t               dst = le64_to_cpu(hdr->dest_nid);
 550         unsigned int             typ = le32_to_cpu(hdr->type);
 551         unsigned int             ptl = -1;
 552
 553         /* NB: called with hold of lnet_net_lock */
 554
 555         /* NB: if Portal is specified, then only PUT and GET will be
 556          * filtered by delay rule */
 557         if (typ == LNET_MSG_PUT)
 558                 ptl = le32_to_cpu(hdr->msg.put.ptl_index);
 559         else if (typ == LNET_MSG_GET)
 560                 ptl = le32_to_cpu(hdr->msg.get.ptl_index);
 561
 562         list_for_each_entry(rule, &the_lnet.ln_delay_rules, dl_link) {
 563                 if (delay_rule_match(rule, src, dst, typ, ptl, msg))
 564                         return true;
 565         }
 566
 567         return false;
 568 }
 569
 570 /** check out delayed messages for send */
 571 static void
 572 delayed_msg_check(struct lnet_delay_rule *rule, bool all,
 573                   struct list_head *msg_list)
 574 {
 575         struct lnet_msg *msg;
 576         struct lnet_msg *tmp;
 577         unsigned long    now = cfs_time_current();
 578
 579         if (!all && rule->dl_msg_send > now)
 580                 return;
 581
 582         spin_lock(&rule->dl_lock);
 583         list_for_each_entry_safe(msg, tmp, &rule->dl_msg_list, msg_list) {
 584                 if (!all && msg->msg_delay_send > now)
 585                         break;
 586
 587                 msg->msg_delay_send = 0;
 588                 list_move_tail(&msg->msg_list, msg_list);
 589         }
 590
 591         if (list_empty(&rule->dl_msg_list)) {
 592                 del_timer(&rule->dl_timer);
 593                 rule->dl_msg_send = -1;
 594
 595         } else if (!list_empty(msg_list)) {
 596                 /* dequeued some timedout messages, update timer for the
 597                  * next delayed message on rule */
 598                 msg = list_entry(rule->dl_msg_list.next,
 599                                  struct lnet_msg, msg_list);
 600                 rule->dl_msg_send = msg->msg_delay_send;
 601                 mod_timer(&rule->dl_timer, rule->dl_msg_send);
 602         }
 603         spin_unlock(&rule->dl_lock);
 604 }
 605
 606 static void
 607 delayed_msg_process(struct list_head *msg_list, bool drop)
 608 {
 609         struct lnet_msg *msg;
 610
 611         while (!list_empty(msg_list)) {
 612                 struct lnet_ni *ni;
 613                 int             cpt;
 614                 int             rc;
 615
 616                 msg = list_entry(msg_list->next, struct lnet_msg, msg_list);
 617                 LASSERT(msg->msg_rxpeer != NULL);
 618                 LASSERT(msg->msg_rxni != NULL);
 619
 620                 ni = msg->msg_rxni;
 621                 cpt = msg->msg_rx_cpt;
 622
 623                 list_del_init(&msg->msg_list);
 624                 if (drop) {
 625                         rc = -ECANCELED;
 626
 627                 } else if (!msg->msg_routing) {
 628                         rc = lnet_parse_local(ni, msg);
 629                         if (rc == 0)
 630                                 continue;
 631
 632                 } else {
 633                         lnet_net_lock(cpt);
 634                         rc = lnet_parse_forward_locked(ni, msg);
 635                         lnet_net_unlock(cpt);
 636
 637                         switch (rc) {
 638                         case LNET_CREDIT_OK:
 639                                 lnet_ni_recv(ni, msg->msg_private, msg, 0,
 640                                              0, msg->msg_len, msg->msg_len);
 641                         case LNET_CREDIT_WAIT:
 642                                 continue;
 643                         default: /* failures */
 644                                 break;
 645                         }
 646                 }
 647
 648                 lnet_drop_message(ni, cpt, msg->msg_private, msg->msg_len);
 649                 lnet_finalize(msg, rc);
 650         }
 651 }
 652
 653 /**
 654  * Process delayed messages for scheduled rules
 655  * This function can either be called by delay_rule_daemon, or by lnet_finalise
 656  */
 657 void
 658 lnet_delay_rule_check(void)
 659 {
 660         struct lnet_delay_rule  *rule;
 661         struct list_head         msgs;
 662
 663         INIT_LIST_HEAD(&msgs);
 664         while (1) {
 665                 if (list_empty(&delay_dd.dd_sched_rules))
 666                         break;
 667
 668                 spin_lock_bh(&delay_dd.dd_lock);
 669                 if (list_empty(&delay_dd.dd_sched_rules)) {
 670                         spin_unlock_bh(&delay_dd.dd_lock);
 671                         break;
 672                 }
 673
 674                 rule = list_entry(delay_dd.dd_sched_rules.next,
 675                                   struct lnet_delay_rule, dl_sched_link);
 676                 list_del_init(&rule->dl_sched_link);
 677                 spin_unlock_bh(&delay_dd.dd_lock);
 678
 679                 delayed_msg_check(rule, false, &msgs);
 680                 delay_rule_decref(rule); /* -1 for delay_dd.dd_sched_rules */
 681         }
 682
 683         if (!list_empty(&msgs))
 684                 delayed_msg_process(&msgs, false);
 685 }
 686
 687 /** deamon thread to handle delayed messages */
 688 static int
 689 lnet_delay_rule_daemon(void *arg)
 690 {
 691         delay_dd.dd_running = 1;
 692         wake_up(&delay_dd.dd_ctl_waitq);
 693
 694         while (delay_dd.dd_running) {
 695                 wait_event_interruptible(delay_dd.dd_waitq,
 696                                          !delay_dd.dd_running ||
 697                                          !list_empty(&delay_dd.dd_sched_rules));
 698                 lnet_delay_rule_check();
 699         }
 700
 701         /* in case more rules have been enqueued after my last check */
 702         lnet_delay_rule_check();
 703         delay_dd.dd_stopped = 1;
 704         wake_up(&delay_dd.dd_ctl_waitq);
 705
 706         return 0;
 707 }
 708
 709 static void
 710 delay_timer_cb(unsigned long arg)
 711 {
 712         struct lnet_delay_rule *rule = (struct lnet_delay_rule *)arg;
 713
 714         spin_lock_bh(&delay_dd.dd_lock);
 715         if (list_empty(&rule->dl_sched_link) && delay_dd.dd_running) {
 716                 atomic_inc(&rule->dl_refcount);
 717                 list_add_tail(&rule->dl_sched_link, &delay_dd.dd_sched_rules);
 718                 wake_up(&delay_dd.dd_waitq);
 719         }
 720         spin_unlock_bh(&delay_dd.dd_lock);
 721 }
 722
 723 /**
 724  * Add a new delay rule to LNet
 725  * There is no check for duplicated delay rule, all rules will be checked for
 726  * incoming message.
 727  */
 728 int
 729 lnet_delay_rule_add(struct lnet_fault_attr *attr)
 730 {
 731         struct lnet_delay_rule *rule;
 732         int                     rc = 0;
 733         ENTRY;
 734
 735         if (!((attr->u.delay.la_rate == 0) ^
 736               (attr->u.delay.la_interval == 0))) {
 737                 CDEBUG(D_NET,
 738                        "please provide either delay rate or delay interval, "
 739                        "but not both at the same time %d/%d\n",
 740                        attr->u.delay.la_rate, attr->u.delay.la_interval);
 741                 RETURN(-EINVAL);
 742         }
 743
 744         if (attr->u.delay.la_latency == 0) {
 745                 CDEBUG(D_NET, "delay latency cannot be zero\n");
 746                 RETURN(-EINVAL);
 747         }
 748
 749         if (lnet_fault_attr_validate(attr) != 0)
 750                 RETURN(-EINVAL);
 751
 752         CFS_ALLOC_PTR(rule);
 753         if (rule == NULL)
 754                 RETURN(-ENOMEM);
 755
 756         mutex_lock(&delay_dd.dd_mutex);
 757         if (!delay_dd.dd_running) {
 758                 struct task_struct *task;
 759
 760                 /* NB: although LND threads will process delayed message
 761                  * in lnet_finalize, but there is no guarantee that LND
 762                  * threads will be waken up if no other message needs to
 763                  * be handled.
 764                  * Only one daemon thread, performance is not the concern
 765                  * of this simualation module.
 766                  */
 767                 task = kthread_run(lnet_delay_rule_daemon, NULL, "lnet_dd");
 768                 if (IS_ERR(task)) {
 769                         rc = PTR_ERR(task);
 770                         GOTO(failed, rc);
 771                 }
 772                 wait_event(delay_dd.dd_ctl_waitq, delay_dd.dd_running);
 773         }
 774
 775         init_timer(&rule->dl_timer);
 776         rule->dl_timer.function = delay_timer_cb;
 777         rule->dl_timer.data = (unsigned long)rule;
 778
 779         spin_lock_init(&rule->dl_lock);
 780         INIT_LIST_HEAD(&rule->dl_msg_list);
 781         INIT_LIST_HEAD(&rule->dl_sched_link);
 782
 783         rule->dl_attr = *attr;
 784         if (attr->u.delay.la_interval != 0) {
 785                 rule->dl_time_base = cfs_time_shift(attr->u.delay.la_interval);
 786                 rule->dl_delay_time = cfs_time_shift(cfs_rand() %
 787                                                      attr->u.delay.la_interval);
 788         } else {
 789                 rule->dl_delay_at = cfs_rand() % attr->u.delay.la_rate;
 790         }
 791
 792         rule->dl_msg_send = -1;
 793
 794         lnet_net_lock(LNET_LOCK_EX);
 795         atomic_set(&rule->dl_refcount, 1);
 796         list_add(&rule->dl_link, &the_lnet.ln_delay_rules);
 797         lnet_net_unlock(LNET_LOCK_EX);
 798
 799         CDEBUG(D_NET, "Added delay rule: src %s, dst %s, rate %d\n",
 800                libcfs_nid2str(attr->fa_src), libcfs_nid2str(attr->fa_src),
 801                attr->u.delay.la_rate);
 802
 803         mutex_unlock(&delay_dd.dd_mutex);
 804         RETURN(0);
 805  failed:
 806         mutex_unlock(&delay_dd.dd_mutex);
 807         CFS_FREE_PTR(rule);
 808         return rc;
 809 }
 810
 811 /**
 812  * Remove matched Delay Rules from lnet, if \a shutdown is true or both \a src
 813  * and \a dst are zero, all rules will be removed, otherwise only matched rules
 814  * will be removed.
 815  * If \a src is zero, then all rules have \a dst as destination will be remove
 816  * If \a dst is zero, then all rules have \a src as source will be removed
 817  *
 818  * When a delay rule is removed, all delayed messages of this rule will be
 819  * processed immediately.
 820  */
 821 int
 822 lnet_delay_rule_del(lnet_nid_t src, lnet_nid_t dst, bool shutdown)
 823 {
 824         struct lnet_delay_rule *rule;
 825         struct lnet_delay_rule  *tmp;
 826         struct list_head        rule_list;
 827         struct list_head        msg_list;
 828         int                     n = 0;
 829         bool                    cleanup;
 830         ENTRY;
 831
 832         INIT_LIST_HEAD(&rule_list);
 833         INIT_LIST_HEAD(&msg_list);
 834
 835         if (shutdown)
 836                 src = dst = 0;
 837
 838         mutex_lock(&delay_dd.dd_mutex);
 839         lnet_net_lock(LNET_LOCK_EX);
 840
 841         list_for_each_entry_safe(rule, tmp, &the_lnet.ln_delay_rules, dl_link) {
 842                 if (rule->dl_attr.fa_src != src && src != 0)
 843                         continue;
 844
 845                 if (rule->dl_attr.fa_dst != dst && dst != 0)
 846                         continue;
 847
 848                 CDEBUG(D_NET, "Remove delay rule: src %s->dst: %s (1/%d, %d)\n",
 849                        libcfs_nid2str(rule->dl_attr.fa_src),
 850                        libcfs_nid2str(rule->dl_attr.fa_dst),
 851                        rule->dl_attr.u.delay.la_rate,
 852                        rule->dl_attr.u.delay.la_interval);
 853                 /* refcount is taken over by rule_list */
 854                 list_move(&rule->dl_link, &rule_list);
 855         }
 856
 857         /* check if we need to shutdown delay_daemon */
 858         cleanup = list_empty(&the_lnet.ln_delay_rules) &&
 859                   !list_empty(&rule_list);
 860         lnet_net_unlock(LNET_LOCK_EX);
 861
 862         list_for_each_entry_safe(rule, tmp, &rule_list, dl_link) {
 863                 list_del_init(&rule->dl_link);
 864
 865                 del_timer_sync(&rule->dl_timer);
 866                 delayed_msg_check(rule, true, &msg_list);
 867                 delay_rule_decref(rule); /* -1 for the_lnet.ln_delay_rules */
 868                 n++;
 869         }
 870
 871         if (cleanup) { /* no more delay rule, shutdown delay_daemon */
 872                 LASSERT(delay_dd.dd_running);
 873                 delay_dd.dd_running = 0;
 874                 wake_up(&delay_dd.dd_waitq);
 875
 876                 while (!delay_dd.dd_stopped)
 877                         wait_event(delay_dd.dd_ctl_waitq, delay_dd.dd_stopped);
 878         }
 879         mutex_unlock(&delay_dd.dd_mutex);
 880
 881         if (!list_empty(&msg_list))
 882                 delayed_msg_process(&msg_list, shutdown);
 883
 884         RETURN(n);
 885 }
 886
 887 /**
 888  * List Delay Rule at position of \a pos
 889  */
 890 int
 891 lnet_delay_rule_list(int pos, struct lnet_fault_attr *attr,
 892                     struct lnet_fault_stat *stat)
 893 {
 894         struct lnet_delay_rule *rule;
 895         int                     cpt;
 896         int                     i = 0;
 897         int                     rc = -ENOENT;
 898         ENTRY;
 899
 900         cpt = lnet_net_lock_current();
 901         list_for_each_entry(rule, &the_lnet.ln_delay_rules, dl_link) {
 902                 if (i++ < pos)
 903                         continue;
 904
 905                 spin_lock(&rule->dl_lock);
 906                 *attr = rule->dl_attr;
 907                 *stat = rule->dl_stat;
 908                 spin_unlock(&rule->dl_lock);
 909                 rc = 0;
 910                 break;
 911         }
 912
 913         lnet_net_unlock(cpt);
 914         RETURN(rc);
 915 }
 916
 917 /**
 918  * reset counters for all Delay Rules
 919  */
 920 void
 921 lnet_delay_rule_reset(void)
 922 {
 923         struct lnet_delay_rule *rule;
 924         int                     cpt;
 925         ENTRY;
 926
 927         cpt = lnet_net_lock_current();
 928
 929         list_for_each_entry(rule, &the_lnet.ln_delay_rules, dl_link) {
 930                 struct lnet_fault_attr *attr = &rule->dl_attr;
 931
 932                 spin_lock(&rule->dl_lock);
 933
 934                 memset(&rule->dl_stat, 0, sizeof(rule->dl_stat));
 935                 if (attr->u.delay.la_rate != 0) {
 936                         rule->dl_delay_at = cfs_rand() % attr->u.delay.la_rate;
 937                 } else {
 938                         rule->dl_delay_time = cfs_time_shift(cfs_rand() %
 939                                                 attr->u.delay.la_interval);
 940                         rule->dl_time_base = cfs_time_shift(attr->u.delay.
 941                                                                   la_interval);
 942                 }
 943                 spin_unlock(&rule->dl_lock);
 944         }
 945
 946         lnet_net_unlock(cpt);
 947         EXIT;
 948 }
 949
 950 int
 951 lnet_fault_ctl(int opc, struct libcfs_ioctl_data *data)
 952 {
 953         struct lnet_fault_attr *attr;
 954         struct lnet_fault_stat *stat;
 955
 956         attr = (struct lnet_fault_attr *)data->ioc_inlbuf1;
 957
 958         switch (opc) {
 959         default:
 960                 return -EINVAL;
 961
 962         case LNET_CTL_DROP_ADD:
 963                 if (attr == NULL)
 964                         return -EINVAL;
 965
 966                 return lnet_drop_rule_add(attr);
 967
 968         case LNET_CTL_DROP_DEL:
 969                 if (attr == NULL)
 970                         return -EINVAL;
 971
 972                 data->ioc_count = lnet_drop_rule_del(attr->fa_src,
 973                                                      attr->fa_dst);
 974                 return 0;
 975
 976         case LNET_CTL_DROP_RESET:
 977                 lnet_drop_rule_reset();
 978                 return 0;
 979
 980         case LNET_CTL_DROP_LIST:
 981                 stat = (struct lnet_fault_stat *)data->ioc_inlbuf2;
 982                 if (attr == NULL || stat == NULL)
 983                         return -EINVAL;
 984
 985                 return lnet_drop_rule_list(data->ioc_count, attr, stat);
 986
 987         case LNET_CTL_DELAY_ADD:
 988                 if (attr == NULL)
 989                         return -EINVAL;
 990
 991                 return lnet_delay_rule_add(attr);
 992
 993         case LNET_CTL_DELAY_DEL:
 994                 if (attr == NULL)
 995                         return -EINVAL;
 996
 997                 data->ioc_count = lnet_delay_rule_del(attr->fa_src,
 998                                                       attr->fa_dst, false);
 999                 return 0;
1000
1001         case LNET_CTL_DELAY_RESET:
1002                 lnet_delay_rule_reset();
1003                 return 0;
1004
1005         case LNET_CTL_DELAY_LIST:
1006                 stat = (struct lnet_fault_stat *)data->ioc_inlbuf2;
1007                 if (attr == NULL || stat == NULL)
1008                         return -EINVAL;
1009
1010                 return lnet_delay_rule_list(data->ioc_count, attr, stat);
1011         }
1012 }
1013
1014 int
1015 lnet_fault_init(void)
1016 {
1017         CLASSERT(LNET_PUT_BIT == 1 << LNET_MSG_PUT);
1018         CLASSERT(LNET_ACK_BIT == 1 << LNET_MSG_ACK);
1019         CLASSERT(LNET_GET_BIT == 1 << LNET_MSG_GET);
1020         CLASSERT(LNET_REPLY_BIT == 1 << LNET_MSG_REPLY);
1021
1022         mutex_init(&delay_dd.dd_mutex);
1023         spin_lock_init(&delay_dd.dd_lock);
1024         init_waitqueue_head(&delay_dd.dd_waitq);
1025         init_waitqueue_head(&delay_dd.dd_ctl_waitq);
1026         INIT_LIST_HEAD(&delay_dd.dd_sched_rules);
1027
1028         return 0;
1029 }
1030
1031 void
1032 lnet_fault_fini(void)
1033 {
1034         lnet_drop_rule_del(0, 0);
1035         lnet_delay_rule_del(0, 0, true);
1036
1037         LASSERT(list_empty(&the_lnet.ln_drop_rules));
1038         LASSERT(list_empty(&the_lnet.ln_delay_rules));
1039         LASSERT(list_empty(&delay_dd.dd_sched_rules));
1040 }