lnet/lnet/router.c

   1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
   2  * vim:expandtab:shiftwidth=8:tabstop=8:
   3  *
   4  * Copyright  2008 Sun Microsystems, Inc. All rights reserved
   5  *
   6  *   This file is part of Portals
   7  *   http://sourceforge.net/projects/sandiaportals/
   8  *
   9  *   Portals is free software; you can redistribute it and/or
  10  *   modify it under the terms of version 2 of the GNU General Public
  11  *   License as published by the Free Software Foundation.
  12  *
  13  *   Portals is distributed in the hope that it will be useful,
  14  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  *   GNU General Public License for more details.
  17  *
  18  *   You should have received a copy of the GNU General Public License
  19  *   along with Portals; if not, write to the Free Software
  20  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  21  *
  22  */
  23
  24 #define DEBUG_SUBSYSTEM S_LNET
  25 #include <lnet/lib-lnet.h>
  26
  27 #if defined(__KERNEL__) && defined(LNET_ROUTER)
  28
  29 static char *forwarding = "";
  30 CFS_MODULE_PARM(forwarding, "s", charp, 0444,
  31                 "Explicitly enable/disable forwarding between networks");
  32
  33 static int tiny_router_buffers = 1024;
  34 CFS_MODULE_PARM(tiny_router_buffers, "i", int, 0444,
  35                 "# of 0 payload messages to buffer in the router");
  36 static int small_router_buffers = 8192;
  37 CFS_MODULE_PARM(small_router_buffers, "i", int, 0444,
  38                 "# of small (1 page) messages to buffer in the router");
  39 static int large_router_buffers = 512;
  40 CFS_MODULE_PARM(large_router_buffers, "i", int, 0444,
  41                 "# of large messages to buffer in the router");
  42 static int peer_buffer_credits = 0;
  43 CFS_MODULE_PARM(peer_buffer_credits, "i", int, 0444,
  44                 "# router buffer credits per peer");
  45
  46 static int auto_down = 1;
  47 CFS_MODULE_PARM(auto_down, "i", int, 0444,
  48                 "Automatically mark peers down on comms error");
  49
  50 int
  51 lnet_peer_buffer_credits(lnet_ni_t *ni)
  52 {
  53         /* NI option overrides LNet default */
  54         if (ni->ni_peerrtrcredits > 0)
  55                 return ni->ni_peerrtrcredits;
  56         if (peer_buffer_credits > 0)
  57                 return peer_buffer_credits;
  58
  59         /* As an approximation, allow this peer the same number of router
  60          * buffers as it is allowed outstanding sends */
  61         return ni->ni_peertxcredits;
  62 }
  63
  64 /* forward ref's */
  65 static int lnet_router_checker(void *);
  66 #else
  67
  68 int
  69 lnet_peer_buffer_credits(lnet_ni_t *ni)
  70 {
  71         return 0;
  72 }
  73
  74 #endif
  75
  76 static int check_routers_before_use = 0;
  77 CFS_MODULE_PARM(check_routers_before_use, "i", int, 0444,
  78                 "Assume routers are down and ping them before use");
  79
  80 static int dead_router_check_interval = 0;
  81 CFS_MODULE_PARM(dead_router_check_interval, "i", int, 0444,
  82                 "Seconds between dead router health checks (<= 0 to disable)");
  83
  84 static int live_router_check_interval = 0;
  85 CFS_MODULE_PARM(live_router_check_interval, "i", int, 0444,
  86                 "Seconds between live router health checks (<= 0 to disable)");
  87
  88 static int router_ping_timeout = 50;
  89 CFS_MODULE_PARM(router_ping_timeout, "i", int, 0444,
  90                 "Seconds to wait for the reply to a router health query");
  91
  92 int
  93 lnet_peers_start_down(void)
  94 {
  95         return check_routers_before_use;
  96 }
  97
  98 void
  99 lnet_notify_locked(lnet_peer_t *lp, int notifylnd, int alive, time_t when)
 100 {
 101         if (when < lp->lp_timestamp) {          /* out of date information */
 102                 CDEBUG(D_NET, "Out of date\n");
 103                 return;
 104         }
 105
 106         lp->lp_timestamp = when;                /* update timestamp */
 107         lp->lp_ping_deadline = 0;               /* disable ping timeout */
 108
 109         if (lp->lp_alive_count != 0 &&          /* got old news */
 110             (!lp->lp_alive) == (!alive)) {      /* new date for old news */
 111                 CDEBUG(D_NET, "Old news\n");
 112                 return;
 113         }
 114
 115         /* Flag that notification is outstanding */
 116
 117         lp->lp_alive_count++;
 118         lp->lp_alive = !(!alive);               /* 1 bit! */
 119         lp->lp_notify = 1;
 120         lp->lp_notifylnd |= notifylnd;
 121
 122         CDEBUG(D_NET, "set %s %d\n", libcfs_nid2str(lp->lp_nid), alive);
 123 }
 124
 125 void
 126 lnet_do_notify (lnet_peer_t *lp)
 127 {
 128         lnet_ni_t *ni = lp->lp_ni;
 129         int        alive;
 130         int        notifylnd;
 131
 132         LNET_LOCK();
 133
 134         /* Notify only in 1 thread at any time to ensure ordered notification.
 135          * NB individual events can be missed; the only guarantee is that you
 136          * always get the most recent news */
 137
 138         if (lp->lp_notifying) {
 139                 LNET_UNLOCK();
 140                 return;
 141         }
 142
 143         lp->lp_notifying = 1;
 144
 145         while (lp->lp_notify) {
 146                 alive     = lp->lp_alive;
 147                 notifylnd = lp->lp_notifylnd;
 148
 149                 lp->lp_notifylnd = 0;
 150                 lp->lp_notify    = 0;
 151
 152                 if (notifylnd && ni->ni_lnd->lnd_notify != NULL) {
 153                         LNET_UNLOCK();
 154
 155                         /* A new notification could happen now; I'll handle it
 156                          * when control returns to me */
 157
 158                         (ni->ni_lnd->lnd_notify)(ni, lp->lp_nid, alive);
 159
 160                         LNET_LOCK();
 161                 }
 162         }
 163
 164         lp->lp_notifying = 0;
 165
 166         LNET_UNLOCK();
 167 }
 168
 169
 170 static void
 171 lnet_rtr_addref_locked(lnet_peer_t *lp)
 172 {
 173         LASSERT (lp->lp_refcount > 0);
 174         LASSERT (lp->lp_rtr_refcount >= 0);
 175
 176         lp->lp_rtr_refcount++;
 177         if (lp->lp_rtr_refcount == 1) {
 178                 struct list_head *pos;
 179
 180                 /* a simple insertion sort */
 181                 list_for_each_prev(pos, &the_lnet.ln_routers) {
 182                         lnet_peer_t *rtr = list_entry(pos, lnet_peer_t,
 183                                                       lp_rtr_list);
 184
 185                         if (rtr->lp_nid < lp->lp_nid)
 186                                 break;
 187                 }
 188
 189                 list_add(&lp->lp_rtr_list, pos);
 190                 /* addref for the_lnet.ln_routers */
 191                 lnet_peer_addref_locked(lp);
 192                 the_lnet.ln_routers_version++;
 193         }
 194 }
 195
 196 static void
 197 lnet_rtr_decref_locked(lnet_peer_t *lp)
 198 {
 199         LASSERT (lp->lp_refcount > 0);
 200         LASSERT (lp->lp_rtr_refcount > 0);
 201
 202         lp->lp_rtr_refcount--;
 203         if (lp->lp_rtr_refcount == 0) {
 204                 list_del(&lp->lp_rtr_list);
 205                 /* decref for the_lnet.ln_routers */
 206                 lnet_peer_decref_locked(lp);
 207                 the_lnet.ln_routers_version++;
 208         }
 209 }
 210
 211 lnet_remotenet_t *
 212 lnet_find_net_locked (__u32 net)
 213 {
 214         lnet_remotenet_t *rnet;
 215         struct list_head *tmp;
 216
 217         LASSERT (!the_lnet.ln_shutdown);
 218
 219         list_for_each (tmp, &the_lnet.ln_remote_nets) {
 220                 rnet = list_entry(tmp, lnet_remotenet_t, lrn_list);
 221
 222                 if (rnet->lrn_net == net)
 223                         return rnet;
 224         }
 225         return NULL;
 226 }
 227
 228 int
 229 lnet_add_route (__u32 net, unsigned int hops, lnet_nid_t gateway)
 230 {
 231         struct list_head     zombies;
 232         struct list_head    *e;
 233         lnet_remotenet_t    *rnet;
 234         lnet_remotenet_t    *rnet2;
 235         lnet_route_t        *route;
 236         lnet_route_t        *route2;
 237         lnet_ni_t           *ni;
 238         int                  add_route;
 239         int                  rc;
 240
 241         CDEBUG(D_NET, "Add route: net %s hops %u gw %s\n",
 242                libcfs_net2str(net), hops, libcfs_nid2str(gateway));
 243
 244         if (gateway == LNET_NID_ANY ||
 245             LNET_NETTYP(LNET_NIDNET(gateway)) == LOLND ||
 246             net == LNET_NIDNET(LNET_NID_ANY) ||
 247             LNET_NETTYP(net) == LOLND ||
 248             LNET_NIDNET(gateway) == net ||
 249             hops < 1 || hops > 255)
 250                 return (-EINVAL);
 251
 252         if (lnet_islocalnet(net))               /* it's a local network */
 253                 return 0;                       /* ignore the route entry */
 254
 255         /* Assume net, route, all new */
 256         LIBCFS_ALLOC(route, sizeof(*route));
 257         LIBCFS_ALLOC(rnet, sizeof(*rnet));
 258         if (route == NULL || rnet == NULL) {
 259                 CERROR("Out of memory creating route %s %d %s\n",
 260                        libcfs_net2str(net), hops, libcfs_nid2str(gateway));
 261                 if (route != NULL)
 262                         LIBCFS_FREE(route, sizeof(*route));
 263                 if (rnet != NULL)
 264                         LIBCFS_FREE(rnet, sizeof(*rnet));
 265                 return -ENOMEM;
 266         }
 267
 268         CFS_INIT_LIST_HEAD(&rnet->lrn_routes);
 269         rnet->lrn_net = net;
 270         rnet->lrn_hops = hops;
 271
 272         LNET_LOCK();
 273
 274         rc = lnet_nid2peer_locked(&route->lr_gateway, gateway);
 275         if (rc != 0) {
 276                 LNET_UNLOCK();
 277
 278                 LIBCFS_FREE(route, sizeof(*route));
 279                 LIBCFS_FREE(rnet, sizeof(*rnet));
 280
 281                 if (rc == -EHOSTUNREACH)        /* gateway is not on a local net */
 282                         return 0;               /* ignore the route entry */
 283
 284                 CERROR("Error %d creating route %s %d %s\n", rc,
 285                        libcfs_net2str(net), hops, libcfs_nid2str(gateway));
 286                 return rc;
 287         }
 288
 289         LASSERT (!the_lnet.ln_shutdown);
 290         CFS_INIT_LIST_HEAD(&zombies);
 291
 292         rnet2 = lnet_find_net_locked(net);
 293         if (rnet2 == NULL) {
 294                 /* new network */
 295                 list_add_tail(&rnet->lrn_list, &the_lnet.ln_remote_nets);
 296                 rnet2 = rnet;
 297         }
 298
 299         if (hops > rnet2->lrn_hops) {
 300                 /* New route is longer; ignore it */
 301                 add_route = 0;
 302         } else if (hops < rnet2->lrn_hops) {
 303                 /* new route supercedes all currently known routes to this
 304                  * net */
 305                 list_add(&zombies, &rnet2->lrn_routes);
 306                 list_del_init(&rnet2->lrn_routes);
 307                 add_route = 1;
 308         } else {
 309                 add_route = 1;
 310                 /* New route has the same hopcount as existing routes; search
 311                  * for a duplicate route (it's a NOOP if it is) */
 312                 list_for_each (e, &rnet2->lrn_routes) {
 313                         route2 = list_entry(e, lnet_route_t, lr_list);
 314
 315                         if (route2->lr_gateway == route->lr_gateway) {
 316                                 add_route = 0;
 317                                 break;
 318                         }
 319
 320                         /* our loopups must be true */
 321                         LASSERT (route2->lr_gateway->lp_nid != gateway);
 322                 }
 323         }
 324
 325         if (add_route) {
 326                 ni = route->lr_gateway->lp_ni;
 327                 lnet_ni_addref_locked(ni);
 328
 329                 LASSERT (rc == 0);
 330                 list_add_tail(&route->lr_list, &rnet2->lrn_routes);
 331                 the_lnet.ln_remote_nets_version++;
 332
 333                 lnet_rtr_addref_locked(route->lr_gateway);
 334
 335                 LNET_UNLOCK();
 336
 337                 /* XXX Assume alive */
 338                 if (ni->ni_lnd->lnd_notify != NULL)
 339                         (ni->ni_lnd->lnd_notify)(ni, gateway, 1);
 340
 341                 lnet_ni_decref(ni);
 342         } else {
 343                 lnet_peer_decref_locked(route->lr_gateway);
 344                 LNET_UNLOCK();
 345                 LIBCFS_FREE(route, sizeof(*route));
 346         }
 347
 348         if (rnet != rnet2)
 349                 LIBCFS_FREE(rnet, sizeof(*rnet));
 350
 351         while (!list_empty(&zombies)) {
 352                 route = list_entry(zombies.next, lnet_route_t, lr_list);
 353                 list_del(&route->lr_list);
 354
 355                 LNET_LOCK();
 356                 lnet_rtr_decref_locked(route->lr_gateway);
 357                 lnet_peer_decref_locked(route->lr_gateway);
 358                 LNET_UNLOCK();
 359                 LIBCFS_FREE(route, sizeof(*route));
 360         }
 361
 362         return rc;
 363 }
 364
 365 int
 366 lnet_check_routes (void)
 367 {
 368         lnet_remotenet_t    *rnet;
 369         lnet_route_t        *route;
 370         lnet_route_t        *route2;
 371         struct list_head    *e1;
 372         struct list_head    *e2;
 373
 374         LNET_LOCK();
 375
 376         list_for_each (e1, &the_lnet.ln_remote_nets) {
 377                 rnet = list_entry(e1, lnet_remotenet_t, lrn_list);
 378
 379                 route2 = NULL;
 380                 list_for_each (e2, &rnet->lrn_routes) {
 381                         route = list_entry(e2, lnet_route_t, lr_list);
 382
 383                         if (route2 == NULL)
 384                                 route2 = route;
 385                         else if (route->lr_gateway->lp_ni !=
 386                                  route2->lr_gateway->lp_ni) {
 387                                 LNET_UNLOCK();
 388
 389                                 CERROR("Routes to %s via %s and %s not supported\n",
 390                                        libcfs_net2str(rnet->lrn_net),
 391                                        libcfs_nid2str(route->lr_gateway->lp_nid),
 392                                        libcfs_nid2str(route2->lr_gateway->lp_nid));
 393                                 return -EINVAL;
 394                         }
 395                 }
 396         }
 397
 398         LNET_UNLOCK();
 399         return 0;
 400 }
 401
 402 int
 403 lnet_del_route (__u32 net, lnet_nid_t gw_nid)
 404 {
 405         lnet_remotenet_t    *rnet;
 406         lnet_route_t        *route;
 407         struct list_head    *e1;
 408         struct list_head    *e2;
 409         int                  rc = -ENOENT;
 410
 411         CDEBUG(D_NET, "Del route: net %s : gw %s\n",
 412                libcfs_net2str(net), libcfs_nid2str(gw_nid));
 413
 414         /* NB Caller may specify either all routes via the given gateway
 415          * or a specific route entry actual NIDs) */
 416
 417  again:
 418         LNET_LOCK();
 419
 420         list_for_each (e1, &the_lnet.ln_remote_nets) {
 421                 rnet = list_entry(e1, lnet_remotenet_t, lrn_list);
 422
 423                 if (!(net == LNET_NIDNET(LNET_NID_ANY) ||
 424                       net == rnet->lrn_net))
 425                         continue;
 426
 427                 list_for_each (e2, &rnet->lrn_routes) {
 428                         route = list_entry(e2, lnet_route_t, lr_list);
 429
 430                         if (!(gw_nid == LNET_NID_ANY ||
 431                               gw_nid == route->lr_gateway->lp_nid))
 432                                 continue;
 433
 434                         list_del(&route->lr_list);
 435                         the_lnet.ln_remote_nets_version++;
 436
 437                         if (list_empty(&rnet->lrn_routes))
 438                                 list_del(&rnet->lrn_list);
 439                         else
 440                                 rnet = NULL;
 441
 442                         lnet_rtr_decref_locked(route->lr_gateway);
 443                         lnet_peer_decref_locked(route->lr_gateway);
 444                         LNET_UNLOCK();
 445
 446                         LIBCFS_FREE(route, sizeof (*route));
 447
 448                         if (rnet != NULL)
 449                                 LIBCFS_FREE(rnet, sizeof(*rnet));
 450
 451                         rc = 0;
 452                         goto again;
 453                 }
 454         }
 455
 456         LNET_UNLOCK();
 457         return rc;
 458 }
 459
 460 void
 461 lnet_destroy_routes (void)
 462 {
 463         lnet_del_route(LNET_NIDNET(LNET_NID_ANY), LNET_NID_ANY);
 464 }
 465
 466 int
 467 lnet_get_route (int idx, __u32 *net, __u32 *hops,
 468                lnet_nid_t *gateway, __u32 *alive)
 469 {
 470         struct list_head    *e1;
 471         struct list_head    *e2;
 472         lnet_remotenet_t    *rnet;
 473         lnet_route_t        *route;
 474
 475         LNET_LOCK();
 476
 477         list_for_each (e1, &the_lnet.ln_remote_nets) {
 478                 rnet = list_entry(e1, lnet_remotenet_t, lrn_list);
 479
 480                 list_for_each (e2, &rnet->lrn_routes) {
 481                         route = list_entry(e2, lnet_route_t, lr_list);
 482
 483                         if (idx-- == 0) {
 484                                 *net     = rnet->lrn_net;
 485                                 *hops    = rnet->lrn_hops;
 486                                 *gateway = route->lr_gateway->lp_nid;
 487                                 *alive   = route->lr_gateway->lp_alive;
 488                                 LNET_UNLOCK();
 489                                 return 0;
 490                         }
 491                 }
 492         }
 493
 494         LNET_UNLOCK();
 495         return -ENOENT;
 496 }
 497
 498 void
 499 lnet_wait_known_routerstate(void)
 500 {
 501         lnet_peer_t         *rtr;
 502         struct list_head    *entry;
 503         int                  all_known;
 504
 505         LASSERT (the_lnet.ln_rc_state == LNET_RC_STATE_RUNNING);
 506
 507         for (;;) {
 508                 LNET_LOCK();
 509
 510                 all_known = 1;
 511                 list_for_each (entry, &the_lnet.ln_routers) {
 512                         rtr = list_entry(entry, lnet_peer_t, lp_rtr_list);
 513
 514                         if (rtr->lp_alive_count == 0) {
 515                                 all_known = 0;
 516                                 break;
 517                         }
 518                 }
 519
 520                 LNET_UNLOCK();
 521
 522                 if (all_known)
 523                         return;
 524
 525 #ifndef __KERNEL__
 526                 lnet_router_checker();
 527 #endif
 528                 cfs_pause(cfs_time_seconds(1));
 529         }
 530 }
 531
 532 static void
 533 lnet_router_checker_event (lnet_event_t *event)
 534 {
 535         /* CAVEAT EMPTOR: I'm called with LNET_LOCKed and I'm not allowed to
 536          * drop it (that's how come I see _every_ event, even ones that would
 537          * overflow my EQ) */
 538         lnet_peer_t   *lp;
 539         lnet_nid_t     nid;
 540
 541         if (event->unlinked) {
 542                 /* The router checker thread has unlinked the rc_md
 543                  * and exited. */
 544                 LASSERT (the_lnet.ln_rc_state == LNET_RC_STATE_UNLINKING);
 545                 the_lnet.ln_rc_state = LNET_RC_STATE_UNLINKED;
 546 #ifdef __KERNEL__
 547                 mutex_up(&the_lnet.ln_rc_signal);
 548 #endif
 549                 return;
 550         }
 551
 552         LASSERT (event->type == LNET_EVENT_SEND ||
 553                  event->type == LNET_EVENT_REPLY);
 554
 555         nid = (event->type == LNET_EVENT_SEND) ?
 556               event->target.nid : event->initiator.nid;
 557
 558         lp = lnet_find_peer_locked(nid);
 559         if (lp == NULL) {
 560                 /* router may have been removed */
 561                 CDEBUG(D_NET, "Router %s not found\n", libcfs_nid2str(nid));
 562                 return;
 563         }
 564
 565         if (event->type == LNET_EVENT_SEND)     /* re-enable another ping */
 566                 lp->lp_ping_notsent = 0;
 567
 568         if (lnet_isrouter(lp) &&                /* ignore if no longer a router */
 569             (event->status != 0 ||
 570              event->type == LNET_EVENT_REPLY)) {
 571
 572                 /* A successful REPLY means the router is up.  If _any_ comms
 573                  * to the router fail I assume it's down (this will happen if
 574                  * we ping alive routers to try to detect router death before
 575                  * apps get burned). */
 576
 577                 lnet_notify_locked(lp, 1, (event->status == 0),
 578                                    cfs_time_current_sec());
 579
 580                 /* The router checker will wake up very shortly and do the
 581                  * actual notification.
 582                  * XXX If 'lp' stops being a router before then, it will still
 583                  * have the notification pending!!! */
 584         }
 585
 586         /* This decref will NOT drop LNET_LOCK (it had to have 1 ref when it
 587          * was in the peer table and I've not dropped the lock, so no-one else
 588          * can have reduced the refcount) */
 589         LASSERT(lp->lp_refcount > 1);
 590
 591         lnet_peer_decref_locked(lp);
 592 }
 593
 594 static int
 595 lnet_router_check_interval (lnet_peer_t *rtr)
 596 {
 597         int secs;
 598
 599         secs = rtr->lp_alive ? live_router_check_interval :
 600                                dead_router_check_interval;
 601         if (secs < 0)
 602                 secs = 0;
 603
 604         return secs;
 605 }
 606
 607 static void
 608 lnet_ping_router_locked (lnet_peer_t *rtr)
 609 {
 610         lnet_process_id_t id;
 611         int               secs;
 612         time_t            now = cfs_time_current_sec();
 613
 614         lnet_peer_addref_locked(rtr);
 615
 616         if (rtr->lp_ping_deadline != 0 && /* ping timed out? */
 617             now > rtr->lp_ping_deadline)
 618                 lnet_notify_locked(rtr, 1, 0, now);
 619
 620         LNET_UNLOCK();
 621
 622         /* Run any outstanding notifications */
 623         lnet_do_notify(rtr);
 624
 625         LNET_LOCK();
 626
 627         secs = lnet_router_check_interval(rtr);
 628
 629         CDEBUG(D_NET,
 630                "rtr %s %d: deadline %lu ping_notsent %d alive %d "
 631                "alive_count %d lp_ping_timestamp %lu\n",
 632                libcfs_nid2str(rtr->lp_nid), secs,
 633                rtr->lp_ping_deadline, rtr->lp_ping_notsent,
 634                rtr->lp_alive, rtr->lp_alive_count, rtr->lp_ping_timestamp);
 635
 636         if (secs != 0 && !rtr->lp_ping_notsent &&
 637             now > rtr->lp_ping_timestamp + secs) {
 638                 id.nid = rtr->lp_nid;
 639                 id.pid = LUSTRE_SRV_LNET_PID;
 640                 CDEBUG(D_NET, "Check: %s\n", libcfs_id2str(id));
 641
 642                 rtr->lp_ping_notsent   = 1;
 643                 rtr->lp_ping_timestamp = now;
 644
 645                 if (rtr->lp_ping_deadline == 0)
 646                         rtr->lp_ping_deadline = now + router_ping_timeout;
 647
 648                 LNET_UNLOCK();
 649
 650                 LNetGet(LNET_NID_ANY, the_lnet.ln_rc_mdh, id,
 651                         LNET_RESERVED_PORTAL, LNET_PROTO_PING_MATCHBITS, 0);
 652
 653                 LNET_LOCK();
 654         }
 655
 656         lnet_peer_decref_locked(rtr);
 657         return;
 658 }
 659
 660 int
 661 lnet_router_checker_start(void)
 662 {
 663         static lnet_ping_info_t pinginfo;
 664
 665         lnet_md_t    md;
 666         int          rc;
 667         int          eqsz;
 668 #ifndef __KERNEL__
 669         lnet_peer_t *rtr;
 670         __u64        version;
 671         int          nrtr = 0;
 672         int          router_checker_max_eqsize = 10240;
 673
 674         LASSERT (check_routers_before_use);
 675         LASSERT (dead_router_check_interval > 0);
 676
 677         LNET_LOCK();
 678
 679         /* As an approximation, allow each router the same number of
 680          * outstanding events as it is allowed outstanding sends */
 681         eqsz = 0;
 682         version = the_lnet.ln_routers_version;
 683         list_for_each_entry(rtr, &the_lnet.ln_routers, lp_rtr_list) {
 684                 lnet_ni_t         *ni = rtr->lp_ni;
 685                 lnet_process_id_t  id;
 686
 687                 nrtr++;
 688                 eqsz += ni->ni_peertxcredits;
 689
 690                 /* one async ping reply per router */
 691                 id.nid = rtr->lp_nid;
 692                 id.pid = LUSTRE_SRV_LNET_PID;
 693
 694                 LNET_UNLOCK();
 695
 696                 rc = LNetSetAsync(id, 1);
 697                 if (rc != 0) {
 698                         CWARN("LNetSetAsync %s failed: %d\n",
 699                               libcfs_id2str(id), rc);
 700                         return rc;
 701                 }
 702
 703                 LNET_LOCK();
 704                 /* NB router list doesn't change in userspace */
 705                 LASSERT (version == the_lnet.ln_routers_version);
 706         }
 707
 708         LNET_UNLOCK();
 709
 710         if (nrtr == 0) {
 711                 CDEBUG(D_NET,
 712                        "No router found, not starting router checker\n");
 713                 return 0;
 714         }
 715
 716         /* at least allow a SENT and a REPLY per router */
 717         if (router_checker_max_eqsize < 2 * nrtr)
 718                 router_checker_max_eqsize = 2 * nrtr;
 719
 720         LASSERT (eqsz > 0);
 721         if (eqsz > router_checker_max_eqsize)
 722                 eqsz = router_checker_max_eqsize;
 723 #endif
 724
 725         LASSERT (the_lnet.ln_rc_state == LNET_RC_STATE_SHUTDOWN);
 726
 727         if (check_routers_before_use &&
 728             dead_router_check_interval <= 0) {
 729                 LCONSOLE_ERROR_MSG(0x10a, "'dead_router_check_interval' must be"
 730                                    " set if 'check_routers_before_use' is set"
 731                                    "\n");
 732                 return -EINVAL;
 733         }
 734
 735         if (live_router_check_interval <= 0 &&
 736             dead_router_check_interval <= 0)
 737                 return 0;
 738
 739 #ifdef __KERNEL__
 740         init_mutex_locked(&the_lnet.ln_rc_signal);
 741         /* EQ size doesn't matter; the callback is guaranteed to get every
 742          * event */
 743         eqsz = 1;
 744         rc = LNetEQAlloc(eqsz, lnet_router_checker_event,
 745                          &the_lnet.ln_rc_eqh);
 746 #else
 747         rc = LNetEQAlloc(eqsz, LNET_EQ_HANDLER_NONE,
 748                          &the_lnet.ln_rc_eqh);
 749 #endif
 750         if (rc != 0) {
 751                 CERROR("Can't allocate EQ(%d): %d\n", eqsz, rc);
 752                 return -ENOMEM;
 753         }
 754
 755         memset(&md, 0, sizeof(md));
 756         md.start     = &pinginfo;
 757         md.length    = sizeof(pinginfo);
 758         md.options   = LNET_MD_TRUNCATE;
 759         md.threshold = LNET_MD_THRESH_INF;
 760         md.eq_handle = the_lnet.ln_rc_eqh;
 761         rc = LNetMDBind(md, LNET_UNLINK, &the_lnet.ln_rc_mdh);
 762         if (rc < 0) {
 763                 CERROR("Can't bind MD: %d\n", rc);
 764                 rc = LNetEQFree(the_lnet.ln_rc_eqh);
 765                 LASSERT (rc == 0);
 766                 return -ENOMEM;
 767         }
 768         LASSERT (rc == 0);
 769
 770         the_lnet.ln_rc_state = LNET_RC_STATE_RUNNING;
 771 #ifdef __KERNEL__
 772         rc = (int)cfs_kernel_thread(lnet_router_checker, NULL, 0);
 773         if (rc < 0) {
 774                 CERROR("Can't start router checker thread: %d\n", rc);
 775                 the_lnet.ln_rc_state = LNET_RC_STATE_UNLINKING;
 776                 rc = LNetMDUnlink(the_lnet.ln_rc_mdh);
 777                 LASSERT (rc == 0);
 778                 /* block until event callback signals exit */
 779                 mutex_down(&the_lnet.ln_rc_signal);
 780                 rc = LNetEQFree(the_lnet.ln_rc_eqh);
 781                 LASSERT (rc == 0);
 782                 the_lnet.ln_rc_state = LNET_RC_STATE_SHUTDOWN;
 783                 return -ENOMEM;
 784         }
 785 #endif
 786
 787         if (check_routers_before_use) {
 788                 /* Note that a helpful side-effect of pinging all known routers
 789                  * at startup is that it makes them drop stale connections they
 790                  * may have to a previous instance of me. */
 791                 lnet_wait_known_routerstate();
 792         }
 793
 794         return 0;
 795 }
 796
 797 void
 798 lnet_router_checker_stop (void)
 799 {
 800         int rc;
 801
 802         if (the_lnet.ln_rc_state == LNET_RC_STATE_SHUTDOWN)
 803                 return;
 804
 805         LASSERT (the_lnet.ln_rc_state == LNET_RC_STATE_RUNNING);
 806         the_lnet.ln_rc_state = LNET_RC_STATE_STOPTHREAD;
 807
 808 #ifdef __KERNEL__
 809         /* block until event callback signals exit */
 810         mutex_down(&the_lnet.ln_rc_signal);
 811 #else
 812         while (the_lnet.ln_rc_state != LNET_RC_STATE_UNLINKED) {
 813                 lnet_router_checker();
 814                 cfs_pause(cfs_time_seconds(1));
 815         }
 816 #endif
 817         LASSERT (the_lnet.ln_rc_state == LNET_RC_STATE_UNLINKED);
 818
 819         rc = LNetEQFree(the_lnet.ln_rc_eqh);
 820         LASSERT (rc == 0);
 821         the_lnet.ln_rc_state = LNET_RC_STATE_SHUTDOWN;
 822         return;
 823 }
 824
 825 #if defined(__KERNEL__) && defined(LNET_ROUTER)
 826
 827 static int
 828 lnet_router_checker(void *arg)
 829 {
 830         int                rc;
 831         lnet_peer_t       *rtr;
 832         struct list_head  *entry;
 833         lnet_process_id_t  rtr_id;
 834
 835         cfs_daemonize("router_checker");
 836         cfs_block_allsigs();
 837
 838         rtr_id.pid = LUSTRE_SRV_LNET_PID;
 839
 840         LASSERT (the_lnet.ln_rc_state == LNET_RC_STATE_RUNNING);
 841
 842         while (the_lnet.ln_rc_state == LNET_RC_STATE_RUNNING) {
 843                 __u64 version;
 844
 845                 LNET_LOCK();
 846 rescan:
 847                 version = the_lnet.ln_routers_version;
 848
 849                 list_for_each (entry, &the_lnet.ln_routers) {
 850                         rtr = list_entry(entry, lnet_peer_t, lp_rtr_list);
 851                         lnet_ping_router_locked(rtr);
 852
 853                         /* NB dropped lock */
 854                         if (version != the_lnet.ln_routers_version) {
 855                                 /* the routers list has changed */
 856                                 goto rescan;
 857                         }
 858                 }
 859
 860                 LNET_UNLOCK();
 861
 862                 /* Call cfs_pause() here always adds 1 to load average
 863                  * because kernel counts # active tasks as nr_running
 864                  * + nr_uninterruptible. */
 865                 cfs_schedule_timeout(CFS_TASK_INTERRUPTIBLE,
 866                                      cfs_time_seconds(1));
 867         }
 868
 869         LASSERT (the_lnet.ln_rc_state == LNET_RC_STATE_STOPTHREAD);
 870         the_lnet.ln_rc_state = LNET_RC_STATE_UNLINKING;
 871
 872         rc = LNetMDUnlink(the_lnet.ln_rc_mdh);
 873         LASSERT (rc == 0);
 874
 875         /* The unlink event callback will signal final completion */
 876         return 0;
 877 }
 878
 879 void
 880 lnet_destroy_rtrbuf(lnet_rtrbuf_t *rb, int npages)
 881 {
 882         int sz = offsetof(lnet_rtrbuf_t, rb_kiov[npages]);
 883
 884         while (--npages >= 0)
 885                 cfs_free_page(rb->rb_kiov[npages].kiov_page);
 886
 887         LIBCFS_FREE(rb, sz);
 888 }
 889
 890 lnet_rtrbuf_t *
 891 lnet_new_rtrbuf(lnet_rtrbufpool_t *rbp)
 892 {
 893         int            npages = rbp->rbp_npages;
 894         int            sz = offsetof(lnet_rtrbuf_t, rb_kiov[npages]);
 895         struct page   *page;
 896         lnet_rtrbuf_t *rb;
 897         int            i;
 898
 899         LIBCFS_ALLOC(rb, sz);
 900         if (rb == NULL)
 901                 return NULL;
 902
 903         rb->rb_pool = rbp;
 904
 905         for (i = 0; i < npages; i++) {
 906                 page = cfs_alloc_page(CFS_ALLOC_ZERO | CFS_ALLOC_STD);
 907                 if (page == NULL) {
 908                         while (--i >= 0)
 909                                 cfs_free_page(rb->rb_kiov[i].kiov_page);
 910
 911                         LIBCFS_FREE(rb, sz);
 912                         return NULL;
 913                 }
 914
 915                 rb->rb_kiov[i].kiov_len = CFS_PAGE_SIZE;
 916                 rb->rb_kiov[i].kiov_offset = 0;
 917                 rb->rb_kiov[i].kiov_page = page;
 918         }
 919
 920         return rb;
 921 }
 922
 923 void
 924 lnet_rtrpool_free_bufs(lnet_rtrbufpool_t *rbp)
 925 {
 926         int            npages = rbp->rbp_npages;
 927         int            nbuffers = 0;
 928         lnet_rtrbuf_t *rb;
 929
 930         LASSERT (list_empty(&rbp->rbp_msgs));
 931         LASSERT (rbp->rbp_credits == rbp->rbp_nbuffers);
 932
 933         while (!list_empty(&rbp->rbp_bufs)) {
 934                 LASSERT (rbp->rbp_credits > 0);
 935
 936                 rb = list_entry(rbp->rbp_bufs.next,
 937                                 lnet_rtrbuf_t, rb_list);
 938                 list_del(&rb->rb_list);
 939                 lnet_destroy_rtrbuf(rb, npages);
 940                 nbuffers++;
 941         }
 942
 943         LASSERT (rbp->rbp_nbuffers == nbuffers);
 944         LASSERT (rbp->rbp_credits == nbuffers);
 945
 946         rbp->rbp_nbuffers = rbp->rbp_credits = 0;
 947 }
 948
 949 int
 950 lnet_rtrpool_alloc_bufs(lnet_rtrbufpool_t *rbp, int nbufs)
 951 {
 952         lnet_rtrbuf_t *rb;
 953         int            i;
 954
 955         if (rbp->rbp_nbuffers != 0) {
 956                 LASSERT (rbp->rbp_nbuffers == nbufs);
 957                 return 0;
 958         }
 959
 960         for (i = 0; i < nbufs; i++) {
 961                 rb = lnet_new_rtrbuf(rbp);
 962
 963                 if (rb == NULL) {
 964                         CERROR("Failed to allocate %d router bufs of %d pages\n",
 965                                nbufs, rbp->rbp_npages);
 966                         return -ENOMEM;
 967                 }
 968
 969                 rbp->rbp_nbuffers++;
 970                 rbp->rbp_credits++;
 971                 rbp->rbp_mincredits++;
 972                 list_add(&rb->rb_list, &rbp->rbp_bufs);
 973
 974                 /* No allocation "under fire" */
 975                 /* Otherwise we'd need code to schedule blocked msgs etc */
 976                 LASSERT (!the_lnet.ln_routing);
 977         }
 978
 979         LASSERT (rbp->rbp_credits == nbufs);
 980         return 0;
 981 }
 982
 983 void
 984 lnet_rtrpool_init(lnet_rtrbufpool_t *rbp, int npages)
 985 {
 986         CFS_INIT_LIST_HEAD(&rbp->rbp_msgs);
 987         CFS_INIT_LIST_HEAD(&rbp->rbp_bufs);
 988
 989         rbp->rbp_npages = npages;
 990         rbp->rbp_credits = 0;
 991         rbp->rbp_mincredits = 0;
 992 }
 993
 994 void
 995 lnet_free_rtrpools(void)
 996 {
 997         lnet_rtrpool_free_bufs(&the_lnet.ln_rtrpools[0]);
 998         lnet_rtrpool_free_bufs(&the_lnet.ln_rtrpools[1]);
 999         lnet_rtrpool_free_bufs(&the_lnet.ln_rtrpools[2]);
1000 }
1001
1002 void
1003 lnet_init_rtrpools(void)
1004 {
1005         int small_pages = 1;
1006         int large_pages = (LNET_MTU + CFS_PAGE_SIZE - 1) >> CFS_PAGE_SHIFT;
1007
1008         lnet_rtrpool_init(&the_lnet.ln_rtrpools[0], 0);
1009         lnet_rtrpool_init(&the_lnet.ln_rtrpools[1], small_pages);
1010         lnet_rtrpool_init(&the_lnet.ln_rtrpools[2], large_pages);
1011 }
1012
1013
1014 int
1015 lnet_alloc_rtrpools(int im_a_router)
1016 {
1017         int       rc;
1018
1019         if (!strcmp(forwarding, "")) {
1020                 /* not set either way */
1021                 if (!im_a_router)
1022                         return 0;
1023         } else if (!strcmp(forwarding, "disabled")) {
1024                 /* explicitly disabled */
1025                 return 0;
1026         } else if (!strcmp(forwarding, "enabled")) {
1027                 /* explicitly enabled */
1028         } else {
1029                 LCONSOLE_ERROR_MSG(0x10b, "'forwarding' not set to either "
1030                                    "'enabled' or 'disabled'\n");
1031                 return -EINVAL;
1032         }
1033
1034         if (tiny_router_buffers <= 0) {
1035                 LCONSOLE_ERROR_MSG(0x10c, "tiny_router_buffers=%d invalid when "
1036                                    "routing enabled\n", tiny_router_buffers);
1037                 rc = -EINVAL;
1038                 goto failed;
1039         }
1040
1041         rc = lnet_rtrpool_alloc_bufs(&the_lnet.ln_rtrpools[0],
1042                                      tiny_router_buffers);
1043         if (rc != 0)
1044                 goto failed;
1045
1046         if (small_router_buffers <= 0) {
1047                 LCONSOLE_ERROR_MSG(0x10d, "small_router_buffers=%d invalid when"
1048                                    " routing enabled\n", small_router_buffers);
1049                 rc = -EINVAL;
1050                 goto failed;
1051         }
1052
1053         rc = lnet_rtrpool_alloc_bufs(&the_lnet.ln_rtrpools[1],
1054                                      small_router_buffers);
1055         if (rc != 0)
1056                 goto failed;
1057
1058         if (large_router_buffers <= 0) {
1059                 LCONSOLE_ERROR_MSG(0x10e, "large_router_buffers=%d invalid when"
1060                                    " routing enabled\n", large_router_buffers);
1061                 rc = -EINVAL;
1062                 goto failed;
1063         }
1064
1065         rc = lnet_rtrpool_alloc_bufs(&the_lnet.ln_rtrpools[2],
1066                                      large_router_buffers);
1067         if (rc != 0)
1068                 goto failed;
1069
1070         LNET_LOCK();
1071         the_lnet.ln_routing = 1;
1072         LNET_UNLOCK();
1073
1074         return 0;
1075
1076  failed:
1077         lnet_free_rtrpools();
1078         return rc;
1079 }
1080
1081 int
1082 lnet_notify (lnet_ni_t *ni, lnet_nid_t nid, int alive, time_t when)
1083 {
1084         lnet_peer_t         *lp = NULL;
1085         time_t               now = cfs_time_current_sec();
1086
1087         LASSERT (!in_interrupt ());
1088
1089         CDEBUG (D_NET, "%s notifying %s: %s\n",
1090                 (ni == NULL) ? "userspace" : libcfs_nid2str(ni->ni_nid),
1091                 libcfs_nid2str(nid),
1092                 alive ? "up" : "down");
1093
1094         if (ni != NULL &&
1095             LNET_NIDNET(ni->ni_nid) != LNET_NIDNET(nid)) {
1096                 CWARN ("Ignoring notification of %s %s by %s (different net)\n",
1097                         libcfs_nid2str(nid), alive ? "birth" : "death",
1098                         libcfs_nid2str(ni->ni_nid));
1099                 return -EINVAL;
1100         }
1101
1102         /* can't do predictions... */
1103         if (when > now) {
1104                 CWARN ("Ignoring prediction from %s of %s %s "
1105                        "%ld seconds in the future\n",
1106                        (ni == NULL) ? "userspace" : libcfs_nid2str(ni->ni_nid),
1107                        libcfs_nid2str(nid), alive ? "up" : "down",
1108                        when - now);
1109                 return -EINVAL;
1110         }
1111
1112         if (ni != NULL && !alive &&             /* LND telling me she's down */
1113             !auto_down) {                       /* auto-down disabled */
1114                 CDEBUG(D_NET, "Auto-down disabled\n");
1115                 return 0;
1116         }
1117
1118         LNET_LOCK();
1119
1120         lp = lnet_find_peer_locked(nid);
1121         if (lp == NULL) {
1122                 /* nid not found */
1123                 LNET_UNLOCK();
1124                 CDEBUG(D_NET, "%s not found\n", libcfs_nid2str(nid));
1125                 return 0;
1126         }
1127
1128         /* We can't fully trust LND on reporting exact peer last_alive
1129          * if he notifies us about dead peer. For example ksocklnd can
1130          * call us with when == _time_when_the_node_was_booted_ if
1131          * no connections were successfully established */
1132         if (ni != NULL && !alive && when < lp->lp_last_alive)
1133                 when = lp->lp_last_alive;
1134
1135         lnet_notify_locked(lp, ni == NULL, alive, when);
1136
1137         LNET_UNLOCK();
1138
1139         lnet_do_notify(lp);
1140
1141         LNET_LOCK();
1142
1143         lnet_peer_decref_locked(lp);
1144
1145         LNET_UNLOCK();
1146         return 0;
1147 }
1148 EXPORT_SYMBOL(lnet_notify);
1149
1150 void
1151 lnet_get_tunables (void)
1152 {
1153         return;
1154 }
1155
1156 #else
1157
1158 int
1159 lnet_notify (lnet_ni_t *ni, lnet_nid_t nid, int alive, time_t when)
1160 {
1161         return -EOPNOTSUPP;
1162 }
1163
1164 void
1165 lnet_router_checker (void)
1166 {
1167         static time_t last = 0;
1168         static int    running = 0;
1169
1170         time_t            now = cfs_time_current_sec();
1171         int               interval = now - last;
1172         int               rc;
1173         __u64             version;
1174         lnet_peer_t      *rtr;
1175
1176         /* It's no use to call me again within a sec - all intervals and
1177          * timeouts are measured in seconds */
1178         if (last != 0 && interval < 2)
1179                 return;
1180
1181         if (last != 0 &&
1182             interval > MAX(live_router_check_interval,
1183                            dead_router_check_interval))
1184                 CDEBUG(D_NETERROR, "Checker(%d/%d) not called for %d seconds\n",
1185                        live_router_check_interval, dead_router_check_interval,
1186                        interval);
1187
1188         LNET_LOCK();
1189         LASSERT (!running); /* recursion check */
1190         running = 1;
1191         LNET_UNLOCK();
1192
1193         last = now;
1194
1195         if (the_lnet.ln_rc_state == LNET_RC_STATE_STOPTHREAD) {
1196                 the_lnet.ln_rc_state = LNET_RC_STATE_UNLINKING;
1197                 rc = LNetMDUnlink(the_lnet.ln_rc_mdh);
1198                 LASSERT (rc == 0);
1199         }
1200
1201         /* consume all pending events */
1202         while (1) {
1203                 int          i;
1204                 lnet_event_t ev;
1205
1206                 /* NB ln_rc_eqh must be the 1st in 'eventqs' otherwise the
1207                  * recursion breaker in LNetEQPoll would fail */
1208                 rc = LNetEQPoll(&the_lnet.ln_rc_eqh, 1, 0, &ev, &i);
1209                 if (rc == 0)   /* no event pending */
1210                         break;
1211
1212                 /* NB a lost SENT prevents me from pinging a router again */
1213                 if (rc == -EOVERFLOW) {
1214                         CERROR("Dropped an event!!!\n");
1215                         abort();
1216                 }
1217
1218                 LASSERT (rc == 1);
1219
1220                 LNET_LOCK();
1221                 lnet_router_checker_event(&ev);
1222                 LNET_UNLOCK();
1223         }
1224
1225         if (the_lnet.ln_rc_state == LNET_RC_STATE_UNLINKED ||
1226             the_lnet.ln_rc_state == LNET_RC_STATE_UNLINKING) {
1227                 running = 0;
1228                 return;
1229         }
1230
1231         LASSERT (the_lnet.ln_rc_state == LNET_RC_STATE_RUNNING);
1232
1233         LNET_LOCK();
1234
1235         version = the_lnet.ln_routers_version;
1236         list_for_each_entry (rtr, &the_lnet.ln_routers, lp_rtr_list) {
1237                 lnet_ping_router_locked(rtr);
1238                 LASSERT (version == the_lnet.ln_routers_version);
1239         }
1240
1241         LNET_UNLOCK();
1242
1243         running = 0; /* lock only needed for the recursion check */
1244         return;
1245 }
1246
1247 /* NB lnet_peers_start_down depends on me,
1248  * so must be called before any peer creation */
1249 void
1250 lnet_get_tunables (void)
1251 {
1252         char *s;
1253
1254         s = getenv("LNET_ROUTER_PING_TIMEOUT");
1255         if (s != NULL) router_ping_timeout = atoi(s);
1256
1257         s = getenv("LNET_LIVE_ROUTER_CHECK_INTERVAL");
1258         if (s != NULL) live_router_check_interval = atoi(s);
1259
1260         s = getenv("LNET_DEAD_ROUTER_CHECK_INTERVAL");
1261         if (s != NULL) dead_router_check_interval = atoi(s);
1262
1263         /* This replaces old lnd_notify mechanism */
1264         check_routers_before_use = 1;
1265         if (dead_router_check_interval <= 0)
1266                 dead_router_check_interval = 30;
1267 }
1268
1269 void
1270 lnet_free_rtrpools (void)
1271 {
1272 }
1273
1274 void
1275 lnet_init_rtrpools (void)
1276 {
1277 }
1278
1279 int
1280 lnet_alloc_rtrpools (int im_a_arouter)
1281 {
1282         return 0;
1283 }
1284
1285 #endif