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 (c) 2007, 2010, Oracle and/or its affiliates. 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 avoid_asym_router_failure = 0;
  81 CFS_MODULE_PARM(avoid_asym_router_failure, "i", int, 0444,
  82                 "Avoid asymmetrical failures: reserved, use at your own risk");
  83
  84 static int dead_router_check_interval = 0;
  85 CFS_MODULE_PARM(dead_router_check_interval, "i", int, 0444,
  86                 "Seconds between dead router health checks (<= 0 to disable)");
  87
  88 static int live_router_check_interval = 0;
  89 CFS_MODULE_PARM(live_router_check_interval, "i", int, 0444,
  90                 "Seconds between live router health checks (<= 0 to disable)");
  91
  92 static int router_ping_timeout = 50;
  93 CFS_MODULE_PARM(router_ping_timeout, "i", int, 0444,
  94                 "Seconds to wait for the reply to a router health query");
  95
  96 int
  97 lnet_peers_start_down(void)
  98 {
  99         return check_routers_before_use;
 100 }
 101
 102 void
 103 lnet_notify_locked(lnet_peer_t *lp, int notifylnd, int alive, cfs_time_t when)
 104 {
 105         if (cfs_time_before(when, lp->lp_timestamp)) { /* out of date information */
 106                 CDEBUG(D_NET, "Out of date\n");
 107                 return;
 108         }
 109
 110         lp->lp_timestamp = when;                /* update timestamp */
 111         lp->lp_ping_deadline = 0;               /* disable ping timeout */
 112
 113         if (lp->lp_alive_count != 0 &&          /* got old news */
 114             (!lp->lp_alive) == (!alive)) {      /* new date for old news */
 115                 CDEBUG(D_NET, "Old news\n");
 116                 return;
 117         }
 118
 119         /* Flag that notification is outstanding */
 120
 121         lp->lp_alive_count++;
 122         lp->lp_alive = !(!alive);               /* 1 bit! */
 123         lp->lp_notify = 1;
 124         lp->lp_notifylnd |= notifylnd;
 125
 126         CDEBUG(D_NET, "set %s %d\n", libcfs_nid2str(lp->lp_nid), alive);
 127 }
 128
 129 void
 130 lnet_do_notify (lnet_peer_t *lp)
 131 {
 132         lnet_ni_t *ni = lp->lp_ni;
 133         int        alive;
 134         int        notifylnd;
 135
 136         LNET_LOCK();
 137
 138         /* Notify only in 1 thread at any time to ensure ordered notification.
 139          * NB individual events can be missed; the only guarantee is that you
 140          * always get the most recent news */
 141
 142         if (lp->lp_notifying) {
 143                 LNET_UNLOCK();
 144                 return;
 145         }
 146
 147         lp->lp_notifying = 1;
 148
 149         while (lp->lp_notify) {
 150                 alive     = lp->lp_alive;
 151                 notifylnd = lp->lp_notifylnd;
 152
 153                 lp->lp_notifylnd = 0;
 154                 lp->lp_notify    = 0;
 155
 156                 if (notifylnd && ni->ni_lnd->lnd_notify != NULL) {
 157                         LNET_UNLOCK();
 158
 159                         /* A new notification could happen now; I'll handle it
 160                          * when control returns to me */
 161
 162                         (ni->ni_lnd->lnd_notify)(ni, lp->lp_nid, alive);
 163
 164                         LNET_LOCK();
 165                 }
 166         }
 167
 168         lp->lp_notifying = 0;
 169
 170         LNET_UNLOCK();
 171 }
 172
 173
 174 static void
 175 lnet_rtr_addref_locked(lnet_peer_t *lp)
 176 {
 177         LASSERT (lp->lp_refcount > 0);
 178         LASSERT (lp->lp_rtr_refcount >= 0);
 179
 180         lp->lp_rtr_refcount++;
 181         if (lp->lp_rtr_refcount == 1) {
 182                 cfs_list_t *pos;
 183
 184                 /* a simple insertion sort */
 185                 cfs_list_for_each_prev(pos, &the_lnet.ln_routers) {
 186                         lnet_peer_t *rtr = cfs_list_entry(pos, lnet_peer_t,
 187                                                           lp_rtr_list);
 188
 189                         if (rtr->lp_nid < lp->lp_nid)
 190                                 break;
 191                 }
 192
 193                 cfs_list_add(&lp->lp_rtr_list, pos);
 194                 /* addref for the_lnet.ln_routers */
 195                 lnet_peer_addref_locked(lp);
 196                 the_lnet.ln_routers_version++;
 197         }
 198 }
 199
 200 static void
 201 lnet_rtr_decref_locked(lnet_peer_t *lp)
 202 {
 203         LASSERT (lp->lp_refcount > 0);
 204         LASSERT (lp->lp_rtr_refcount > 0);
 205
 206         lp->lp_rtr_refcount--;
 207         if (lp->lp_rtr_refcount == 0) {
 208                 if (lp->lp_rcd != NULL) {
 209                         cfs_list_add(&lp->lp_rcd->rcd_list,
 210                                      &the_lnet.ln_zombie_rcd);
 211                         lp->lp_rcd = NULL;
 212                 }
 213
 214                 cfs_list_del(&lp->lp_rtr_list);
 215                 /* decref for the_lnet.ln_routers */
 216                 lnet_peer_decref_locked(lp);
 217                 the_lnet.ln_routers_version++;
 218         }
 219 }
 220
 221 lnet_remotenet_t *
 222 lnet_find_net_locked (__u32 net)
 223 {
 224         lnet_remotenet_t *rnet;
 225         cfs_list_t       *tmp;
 226
 227         LASSERT (!the_lnet.ln_shutdown);
 228
 229         cfs_list_for_each (tmp, &the_lnet.ln_remote_nets) {
 230                 rnet = cfs_list_entry(tmp, lnet_remotenet_t, lrn_list);
 231
 232                 if (rnet->lrn_net == net)
 233                         return rnet;
 234         }
 235         return NULL;
 236 }
 237
 238 /* NB expects LNET_LOCK held */
 239 void
 240 lnet_add_route_to_rnet (lnet_remotenet_t *rnet, lnet_route_t *route)
 241 {
 242         unsigned int      len = 0;
 243         unsigned int      offset = 0;
 244         cfs_list_t       *e;
 245         extern __u64 lnet_create_interface_cookie(void);
 246
 247         cfs_list_for_each (e, &rnet->lrn_routes) {
 248                 len++;
 249         }
 250
 251         /* FIXME use Lustre random function when it's moved to libcfs.
 252          * See bug 18751 */
 253         /* len+1 positions to add a new entry, also prevents division by 0 */
 254         offset = ((unsigned int) lnet_create_interface_cookie()) % (len + 1);
 255         cfs_list_for_each (e, &rnet->lrn_routes) {
 256                 if (offset == 0)
 257                         break;
 258                 offset--;
 259         }
 260         cfs_list_add(&route->lr_list, e);
 261
 262         the_lnet.ln_remote_nets_version++;
 263         lnet_rtr_addref_locked(route->lr_gateway);
 264 }
 265
 266 int
 267 lnet_add_route (__u32 net, unsigned int hops, lnet_nid_t gateway)
 268 {
 269         cfs_list_t          *e;
 270         lnet_remotenet_t    *rnet;
 271         lnet_remotenet_t    *rnet2;
 272         lnet_route_t        *route;
 273         lnet_ni_t           *ni;
 274         int                  add_route;
 275         int                  rc;
 276
 277         CDEBUG(D_NET, "Add route: net %s hops %u gw %s\n",
 278                libcfs_net2str(net), hops, libcfs_nid2str(gateway));
 279
 280         if (gateway == LNET_NID_ANY ||
 281             LNET_NETTYP(LNET_NIDNET(gateway)) == LOLND ||
 282             net == LNET_NIDNET(LNET_NID_ANY) ||
 283             LNET_NETTYP(net) == LOLND ||
 284             LNET_NIDNET(gateway) == net ||
 285             hops < 1 || hops > 255)
 286                 return (-EINVAL);
 287
 288         if (lnet_islocalnet(net))               /* it's a local network */
 289                 return 0;                       /* ignore the route entry */
 290
 291         /* Assume net, route, all new */
 292         LIBCFS_ALLOC(route, sizeof(*route));
 293         LIBCFS_ALLOC(rnet, sizeof(*rnet));
 294         if (route == NULL || rnet == NULL) {
 295                 CERROR("Out of memory creating route %s %d %s\n",
 296                        libcfs_net2str(net), hops, libcfs_nid2str(gateway));
 297                 if (route != NULL)
 298                         LIBCFS_FREE(route, sizeof(*route));
 299                 if (rnet != NULL)
 300                         LIBCFS_FREE(rnet, sizeof(*rnet));
 301                 return -ENOMEM;
 302         }
 303
 304         CFS_INIT_LIST_HEAD(&rnet->lrn_routes);
 305         rnet->lrn_net = net;
 306         route->lr_hops = hops;
 307
 308         LNET_LOCK();
 309
 310         rc = lnet_nid2peer_locked(&route->lr_gateway, gateway);
 311         if (rc != 0) {
 312                 LNET_UNLOCK();
 313
 314                 LIBCFS_FREE(route, sizeof(*route));
 315                 LIBCFS_FREE(rnet, sizeof(*rnet));
 316
 317                 if (rc == -EHOSTUNREACH)        /* gateway is not on a local net */
 318                         return 0;               /* ignore the route entry */
 319
 320                 CERROR("Error %d creating route %s %d %s\n", rc,
 321                        libcfs_net2str(net), hops, libcfs_nid2str(gateway));
 322                 return rc;
 323         }
 324
 325         LASSERT (!the_lnet.ln_shutdown);
 326
 327         rnet2 = lnet_find_net_locked(net);
 328         if (rnet2 == NULL) {
 329                 /* new network */
 330                 cfs_list_add_tail(&rnet->lrn_list, &the_lnet.ln_remote_nets);
 331                 rnet2 = rnet;
 332         }
 333
 334         /* Search for a duplicate route (it's a NOOP if it is) */
 335         add_route = 1;
 336         cfs_list_for_each (e, &rnet2->lrn_routes) {
 337                 lnet_route_t *route2 = cfs_list_entry(e, lnet_route_t, lr_list);
 338
 339                 if (route2->lr_gateway == route->lr_gateway) {
 340                         add_route = 0;
 341                         break;
 342                 }
 343
 344                 /* our lookups must be true */
 345                 LASSERT (route2->lr_gateway->lp_nid != gateway);
 346         }
 347
 348         if (add_route) {
 349                 ni = route->lr_gateway->lp_ni;
 350                 lnet_ni_addref_locked(ni);
 351
 352                 lnet_add_route_to_rnet(rnet2, route);
 353                 LNET_UNLOCK();
 354
 355                 /* XXX Assume alive */
 356                 if (ni->ni_lnd->lnd_notify != NULL)
 357                         (ni->ni_lnd->lnd_notify)(ni, gateway, 1);
 358
 359                 lnet_ni_decref(ni);
 360         } else {
 361                 lnet_peer_decref_locked(route->lr_gateway);
 362                 LNET_UNLOCK();
 363                 LIBCFS_FREE(route, sizeof(*route));
 364         }
 365
 366         if (rnet != rnet2)
 367                 LIBCFS_FREE(rnet, sizeof(*rnet));
 368
 369         return 0;
 370 }
 371
 372 int
 373 lnet_check_routes (void)
 374 {
 375         lnet_remotenet_t    *rnet;
 376         lnet_route_t        *route;
 377         lnet_route_t        *route2;
 378         cfs_list_t          *e1;
 379         cfs_list_t          *e2;
 380
 381         LNET_LOCK();
 382
 383         cfs_list_for_each (e1, &the_lnet.ln_remote_nets) {
 384                 rnet = cfs_list_entry(e1, lnet_remotenet_t, lrn_list);
 385
 386                 route2 = NULL;
 387                 cfs_list_for_each (e2, &rnet->lrn_routes) {
 388                         route = cfs_list_entry(e2, lnet_route_t, lr_list);
 389
 390                         if (route2 == NULL)
 391                                 route2 = route;
 392                         else if (route->lr_gateway->lp_ni !=
 393                                  route2->lr_gateway->lp_ni) {
 394                                 LNET_UNLOCK();
 395
 396                                 CERROR("Routes to %s via %s and %s not supported\n",
 397                                        libcfs_net2str(rnet->lrn_net),
 398                                        libcfs_nid2str(route->lr_gateway->lp_nid),
 399                                        libcfs_nid2str(route2->lr_gateway->lp_nid));
 400                                 return -EINVAL;
 401                         }
 402                 }
 403         }
 404
 405         LNET_UNLOCK();
 406         return 0;
 407 }
 408
 409 int
 410 lnet_del_route (__u32 net, lnet_nid_t gw_nid)
 411 {
 412         lnet_remotenet_t    *rnet;
 413         lnet_route_t        *route;
 414         cfs_list_t          *e1;
 415         cfs_list_t          *e2;
 416         int                  rc = -ENOENT;
 417
 418         CDEBUG(D_NET, "Del route: net %s : gw %s\n",
 419                libcfs_net2str(net), libcfs_nid2str(gw_nid));
 420
 421         /* NB Caller may specify either all routes via the given gateway
 422          * or a specific route entry actual NIDs) */
 423
 424  again:
 425         LNET_LOCK();
 426
 427         cfs_list_for_each (e1, &the_lnet.ln_remote_nets) {
 428                 rnet = cfs_list_entry(e1, lnet_remotenet_t, lrn_list);
 429
 430                 if (!(net == LNET_NIDNET(LNET_NID_ANY) ||
 431                       net == rnet->lrn_net))
 432                         continue;
 433
 434                 cfs_list_for_each (e2, &rnet->lrn_routes) {
 435                         route = cfs_list_entry(e2, lnet_route_t, lr_list);
 436
 437                         if (!(gw_nid == LNET_NID_ANY ||
 438                               gw_nid == route->lr_gateway->lp_nid))
 439                                 continue;
 440
 441                         cfs_list_del(&route->lr_list);
 442                         the_lnet.ln_remote_nets_version++;
 443
 444                         if (cfs_list_empty(&rnet->lrn_routes))
 445                                 cfs_list_del(&rnet->lrn_list);
 446                         else
 447                                 rnet = NULL;
 448
 449                         lnet_rtr_decref_locked(route->lr_gateway);
 450                         lnet_peer_decref_locked(route->lr_gateway);
 451                         LNET_UNLOCK();
 452
 453                         LIBCFS_FREE(route, sizeof (*route));
 454
 455                         if (rnet != NULL)
 456                                 LIBCFS_FREE(rnet, sizeof(*rnet));
 457
 458                         rc = 0;
 459                         goto again;
 460                 }
 461         }
 462
 463         LNET_UNLOCK();
 464         return rc;
 465 }
 466
 467 void
 468 lnet_destroy_routes (void)
 469 {
 470         lnet_del_route(LNET_NIDNET(LNET_NID_ANY), LNET_NID_ANY);
 471 }
 472
 473 int
 474 lnet_get_route (int idx, __u32 *net, __u32 *hops,
 475                lnet_nid_t *gateway, __u32 *alive)
 476 {
 477         cfs_list_t          *e1;
 478         cfs_list_t          *e2;
 479         lnet_remotenet_t    *rnet;
 480         lnet_route_t        *route;
 481
 482         LNET_LOCK();
 483
 484         cfs_list_for_each (e1, &the_lnet.ln_remote_nets) {
 485                 rnet = cfs_list_entry(e1, lnet_remotenet_t, lrn_list);
 486
 487                 cfs_list_for_each (e2, &rnet->lrn_routes) {
 488                         route = cfs_list_entry(e2, lnet_route_t, lr_list);
 489
 490                         if (idx-- == 0) {
 491                                 *net     = rnet->lrn_net;
 492                                 *hops    = route->lr_hops;
 493                                 *gateway = route->lr_gateway->lp_nid;
 494                                 *alive   = route->lr_gateway->lp_alive;
 495                                 LNET_UNLOCK();
 496                                 return 0;
 497                         }
 498                 }
 499         }
 500
 501         LNET_UNLOCK();
 502         return -ENOENT;
 503 }
 504
 505 void
 506 lnet_swap_pinginfo(lnet_ping_info_t *info)
 507 {
 508         int               i;
 509         lnet_ni_status_t *stat;
 510
 511         __swab32s(&info->pi_version);
 512         __swab32s(&info->pi_pid);
 513         __swab32s(&info->pi_nnis);
 514         for (i = 0; i < info->pi_nnis && i < LNET_MAX_RTR_NIS; i++) {
 515                 stat = &info->pi_ni[i];
 516                 __swab64s(&stat->ns_nid);
 517                 __swab32s(&stat->ns_status);
 518         }
 519         return;
 520 }
 521
 522 /* Returns # of down NIs, or negative error codes; ignore downed NIs
 523  * if a NI in 'net' is up */
 524 int
 525 lnet_router_down_ni(lnet_peer_t *rtr, __u32 net)
 526 {
 527         int               i;
 528         int               down = 0;
 529         int               ptl_up = 0;
 530         int               ptl_down = 0;
 531         lnet_ping_info_t *info;
 532
 533         if (!avoid_asym_router_failure)
 534                 return -ENOENT;
 535
 536         if (rtr->lp_rcd == NULL)
 537                 return -EINVAL;
 538
 539         if (!rtr->lp_alive)
 540                 return -EINVAL;  /* stale lp_rcd */
 541
 542         info = rtr->lp_rcd->rcd_pinginfo;
 543         LASSERT (info != NULL);
 544
 545         /* NB always racing with network! */
 546         if (info->pi_magic == __swab32(LNET_PROTO_PING_MAGIC)) {
 547                 lnet_swap_pinginfo(info);
 548         } else if (info->pi_magic != LNET_PROTO_PING_MAGIC) {
 549                 CNETERR("%s: Unexpected magic %08x\n",
 550                         libcfs_nid2str(rtr->lp_nid), info->pi_magic);
 551                 return -EPROTO;
 552         }
 553
 554         if (info->pi_version == LNET_PROTO_PING_VERSION1)
 555                 return -ENOENT;  /* v1 doesn't carry NI status info */
 556
 557         if (info->pi_version != LNET_PROTO_PING_VERSION) {
 558                 CNETERR("%s: Unexpected version 0x%x\n",
 559                         libcfs_nid2str(rtr->lp_nid), info->pi_version);
 560                 return -EPROTO;
 561         }
 562
 563         for (i = 0; i < info->pi_nnis && i < LNET_MAX_RTR_NIS; i++) {
 564                 lnet_ni_status_t *stat = &info->pi_ni[i];
 565                 lnet_nid_t        nid = stat->ns_nid;
 566
 567                 if (nid == LNET_NID_ANY) {
 568                         CNETERR("%s: unexpected LNET_NID_ANY\n",
 569                                 libcfs_nid2str(rtr->lp_nid));
 570                         return -EPROTO;
 571                 }
 572
 573                 if (LNET_NETTYP(LNET_NIDNET(nid)) == LOLND)
 574                         continue;
 575
 576                 if (stat->ns_status == LNET_NI_STATUS_DOWN) {
 577                         if (LNET_NETTYP(LNET_NIDNET(nid)) == PTLLND)
 578                                 ptl_down = 1;
 579                         else
 580                                 down++;
 581                         continue;
 582                 }
 583
 584                 if (stat->ns_status != LNET_NI_STATUS_UP) {
 585                         CNETERR("%s: Unexpected status 0x%x\n",
 586                                 libcfs_nid2str(rtr->lp_nid), stat->ns_status);
 587                         return -EPROTO;
 588                 }
 589
 590                 /* ignore downed NIs if there's a NI up for dest network */
 591                 if (LNET_NIDNET(nid) == net)
 592                         return 0;
 593
 594                 if (LNET_NETTYP(LNET_NIDNET(nid)) == PTLLND)
 595                         ptl_up = 1;
 596         }
 597
 598         /* ptl NIs are considered down only when they're all down */
 599         return down + (ptl_up ? 0 : ptl_down);
 600 }
 601
 602 void
 603 lnet_wait_known_routerstate(void)
 604 {
 605         lnet_peer_t         *rtr;
 606         cfs_list_t          *entry;
 607         int                  all_known;
 608
 609         LASSERT (the_lnet.ln_rc_state == LNET_RC_STATE_RUNNING);
 610
 611         for (;;) {
 612                 LNET_LOCK();
 613
 614                 all_known = 1;
 615                 cfs_list_for_each (entry, &the_lnet.ln_routers) {
 616                         rtr = cfs_list_entry(entry, lnet_peer_t, lp_rtr_list);
 617
 618                         if (rtr->lp_alive_count == 0) {
 619                                 all_known = 0;
 620                                 break;
 621                         }
 622                 }
 623
 624                 LNET_UNLOCK();
 625
 626                 if (all_known)
 627                         return;
 628
 629 #ifndef __KERNEL__
 630                 lnet_router_checker();
 631 #endif
 632                 cfs_pause(cfs_time_seconds(1));
 633         }
 634 }
 635
 636 static void
 637 lnet_router_checker_event (lnet_event_t *event)
 638 {
 639         /* CAVEAT EMPTOR: I'm called with LNET_LOCKed and I'm not allowed to
 640          * drop it (that's how come I see _every_ event, even ones that would
 641          * overflow my EQ) */
 642         lnet_rc_data_t *rcd = event->md.user_ptr;
 643         lnet_peer_t    *lp;
 644         lnet_nid_t      nid;
 645
 646         if (event->unlinked) {
 647                 if (rcd != NULL) {
 648                         LNetInvalidateHandle(&rcd->rcd_mdh);
 649                         return;
 650                 }
 651
 652                 /* The router checker thread has unlinked the default rc_md
 653                  * and exited. */
 654                 LASSERT (the_lnet.ln_rc_state == LNET_RC_STATE_UNLINKING);
 655                 the_lnet.ln_rc_state = LNET_RC_STATE_UNLINKED;
 656 #ifdef __KERNEL__
 657                 cfs_mutex_up(&the_lnet.ln_rc_signal);
 658 #endif
 659                 return;
 660         }
 661
 662         LASSERT (event->type == LNET_EVENT_SEND ||
 663                  event->type == LNET_EVENT_REPLY);
 664
 665         nid = (event->type == LNET_EVENT_SEND) ?
 666               event->target.nid : event->initiator.nid;
 667
 668         lp = lnet_find_peer_locked(nid);
 669         if (lp == NULL) {
 670                 /* router may have been removed */
 671                 CDEBUG(D_NET, "Router %s not found\n", libcfs_nid2str(nid));
 672                 return;
 673         }
 674
 675         if (event->type == LNET_EVENT_SEND)     /* re-enable another ping */
 676                 lp->lp_ping_notsent = 0;
 677
 678         if (lnet_isrouter(lp) &&                /* ignore if no longer a router */
 679             (event->status != 0 ||
 680              event->type == LNET_EVENT_REPLY)) {
 681
 682                 /* A successful REPLY means the router is up.  If _any_ comms
 683                  * to the router fail I assume it's down (this will happen if
 684                  * we ping alive routers to try to detect router death before
 685                  * apps get burned). */
 686
 687                 lnet_notify_locked(lp, 1, (event->status == 0),
 688                                    cfs_time_current());
 689
 690                 /* The router checker will wake up very shortly and do the
 691                  * actual notification.
 692                  * XXX If 'lp' stops being a router before then, it will still
 693                  * have the notification pending!!! */
 694         }
 695
 696         /* This decref will NOT drop LNET_LOCK (it had to have 1 ref when it
 697          * was in the peer table and I've not dropped the lock, so no-one else
 698          * can have reduced the refcount) */
 699         LASSERT(lp->lp_refcount > 1);
 700
 701         lnet_peer_decref_locked(lp);
 702 }
 703
 704 void
 705 lnet_update_ni_status(void)
 706 {
 707         cfs_time_t now = cfs_time_current();
 708         lnet_ni_t *ni;
 709         int        status;
 710         int        timeout;
 711
 712         LASSERT (the_lnet.ln_routing);
 713
 714         timeout = router_ping_timeout +
 715                   MAX(live_router_check_interval, dead_router_check_interval);
 716
 717         LNET_LOCK();
 718
 719         cfs_list_for_each_entry (ni, &the_lnet.ln_nis, ni_list) {
 720                 lnet_ni_status_t *ns = ni->ni_status;
 721
 722                 LASSERT (ns != NULL);
 723
 724                 status = LNET_NI_STATUS_UP;
 725                 if (ni->ni_lnd->lnd_type != LOLND &&  /* @lo forever alive */
 726                     cfs_time_after(now, cfs_time_add(ni->ni_last_alive,
 727                                                      cfs_time_seconds(timeout))))
 728                         status = LNET_NI_STATUS_DOWN;
 729
 730                 if (ns->ns_status != status) {
 731                         ns->ns_status = status;
 732                         CDEBUG(D_NET, "NI(%s:%d) status changed to %s\n",
 733                                libcfs_nid2str(ni->ni_nid), timeout,
 734                                status == LNET_NI_STATUS_UP ? "up" : "down");
 735                 }
 736         }
 737
 738         LNET_UNLOCK();
 739 }
 740
 741 void
 742 lnet_destroy_rc_data (lnet_rc_data_t *rcd)
 743 {
 744         LASSERT (cfs_list_empty(&rcd->rcd_list));
 745         /* detached from network */
 746         LASSERT (LNetHandleIsInvalid(rcd->rcd_mdh));
 747
 748         LIBCFS_FREE(rcd->rcd_pinginfo, LNET_PINGINFO_SIZE);
 749         LIBCFS_FREE(rcd, sizeof(*rcd));
 750         return;
 751 }
 752
 753 lnet_rc_data_t *
 754 lnet_create_rc_data (void)
 755 {
 756         int               i;
 757         int               rc;
 758         lnet_ping_info_t *pi;
 759         lnet_rc_data_t   *rcd;
 760
 761         LIBCFS_ALLOC(rcd, sizeof(*rcd));
 762         if (rcd == NULL)
 763                 return NULL;
 764
 765         LIBCFS_ALLOC(pi, LNET_PINGINFO_SIZE);
 766         if (pi == NULL) {
 767                 LIBCFS_FREE(rcd, sizeof(*rcd));
 768                 return NULL;
 769         }
 770
 771         memset(pi, 0, LNET_PINGINFO_SIZE);
 772         for (i = 0; i < LNET_MAX_RTR_NIS; i++) {
 773                 pi->pi_ni[i].ns_nid = LNET_NID_ANY;
 774                 pi->pi_ni[i].ns_status = LNET_NI_STATUS_INVALID;
 775         }
 776         rcd->rcd_pinginfo = pi;
 777         LNetInvalidateHandle(&rcd->rcd_mdh);
 778         CFS_INIT_LIST_HEAD(&rcd->rcd_list);
 779
 780         LASSERT (!LNetHandleIsInvalid(the_lnet.ln_rc_eqh));
 781         rc = LNetMDBind((lnet_md_t){.start     = pi,
 782                                     .user_ptr  = rcd,
 783                                     .length    = LNET_PINGINFO_SIZE,
 784                                     .threshold = LNET_MD_THRESH_INF,
 785                                     .options   = LNET_MD_TRUNCATE,
 786                                     .eq_handle = the_lnet.ln_rc_eqh},
 787                         LNET_UNLINK,
 788                         &rcd->rcd_mdh);
 789         if (rc < 0) {
 790                 CERROR("Can't bind MD: %d\n", rc);
 791                 lnet_destroy_rc_data(rcd);
 792                 return NULL;
 793         }
 794         LASSERT (rc == 0);
 795         return rcd;
 796 }
 797
 798 static int
 799 lnet_router_check_interval (lnet_peer_t *rtr)
 800 {
 801         int secs;
 802
 803         secs = rtr->lp_alive ? live_router_check_interval :
 804                                dead_router_check_interval;
 805         if (secs < 0)
 806                 secs = 0;
 807
 808         return secs;
 809 }
 810
 811 static void
 812 lnet_ping_router_locked (lnet_peer_t *rtr)
 813 {
 814         int             newrcd = 0;
 815         lnet_rc_data_t *rcd = NULL;
 816         cfs_time_t      now = cfs_time_current();
 817         int             secs;
 818
 819         lnet_peer_addref_locked(rtr);
 820
 821         if (rtr->lp_ping_deadline != 0 && /* ping timed out? */
 822             cfs_time_after(now, rtr->lp_ping_deadline))
 823                 lnet_notify_locked(rtr, 1, 0, now);
 824
 825         if (avoid_asym_router_failure && rtr->lp_rcd == NULL)
 826                 newrcd = 1;
 827
 828         LNET_UNLOCK();
 829
 830         /* Run any outstanding notifications */
 831         lnet_do_notify(rtr);
 832
 833         if (newrcd)
 834                 rcd = lnet_create_rc_data();
 835
 836         LNET_LOCK();
 837
 838         if (!lnet_isrouter(rtr)) {
 839                 lnet_peer_decref_locked(rtr);
 840                 if (rcd != NULL)
 841                         cfs_list_add(&rcd->rcd_list, &the_lnet.ln_zombie_rcd);
 842                 return; /* router table changed! */
 843         }
 844
 845         if (rcd != NULL) {
 846                 LASSERT (rtr->lp_rcd == NULL);
 847                 rtr->lp_rcd = rcd;
 848         }
 849
 850         secs = lnet_router_check_interval(rtr);
 851
 852         CDEBUG(D_NET,
 853                "rtr %s %d: deadline %lu ping_notsent %d alive %d "
 854                "alive_count %d lp_ping_timestamp %lu\n",
 855                libcfs_nid2str(rtr->lp_nid), secs,
 856                rtr->lp_ping_deadline, rtr->lp_ping_notsent,
 857                rtr->lp_alive, rtr->lp_alive_count, rtr->lp_ping_timestamp);
 858
 859         if (secs != 0 && !rtr->lp_ping_notsent &&
 860             cfs_time_after(now, cfs_time_add(rtr->lp_ping_timestamp,
 861                                              cfs_time_seconds(secs)))) {
 862                 int               rc;
 863                 lnet_process_id_t id;
 864                 lnet_handle_md_t  mdh;
 865
 866                 id.nid = rtr->lp_nid;
 867                 id.pid = LUSTRE_SRV_LNET_PID;
 868                 CDEBUG(D_NET, "Check: %s\n", libcfs_id2str(id));
 869
 870                 rtr->lp_ping_notsent   = 1;
 871                 rtr->lp_ping_timestamp = now;
 872                 mdh = (rtr->lp_rcd == NULL) ? the_lnet.ln_rc_mdh :
 873                                               rtr->lp_rcd->rcd_mdh;
 874
 875                 if (rtr->lp_ping_deadline == 0)
 876                         rtr->lp_ping_deadline = cfs_time_shift(router_ping_timeout);
 877
 878                 LNET_UNLOCK();
 879
 880                 rc = LNetGet(LNET_NID_ANY, mdh, id, LNET_RESERVED_PORTAL,
 881                              LNET_PROTO_PING_MATCHBITS, 0);
 882
 883                 LNET_LOCK();
 884                 if (rc != 0)
 885                         rtr->lp_ping_notsent = 0; /* no event pending */
 886         }
 887
 888         lnet_peer_decref_locked(rtr);
 889         return;
 890 }
 891
 892 int
 893 lnet_router_checker_start(void)
 894 {
 895         static lnet_ping_info_t pinginfo;
 896
 897         lnet_md_t    md;
 898         int          rc;
 899         int          eqsz;
 900 #ifndef __KERNEL__
 901         lnet_peer_t *rtr;
 902         __u64        version;
 903         int          nrtr = 0;
 904         int          router_checker_max_eqsize = 10240;
 905
 906         LASSERT (check_routers_before_use);
 907         LASSERT (dead_router_check_interval > 0);
 908
 909         LNET_LOCK();
 910
 911         /* As an approximation, allow each router the same number of
 912          * outstanding events as it is allowed outstanding sends */
 913         eqsz = 0;
 914         version = the_lnet.ln_routers_version;
 915         cfs_list_for_each_entry(rtr, &the_lnet.ln_routers, lp_rtr_list) {
 916                 lnet_ni_t         *ni = rtr->lp_ni;
 917                 lnet_process_id_t  id;
 918
 919                 nrtr++;
 920                 eqsz += ni->ni_peertxcredits;
 921
 922                 /* one async ping reply per router */
 923                 id.nid = rtr->lp_nid;
 924                 id.pid = LUSTRE_SRV_LNET_PID;
 925
 926                 LNET_UNLOCK();
 927
 928                 rc = LNetSetAsync(id, 1);
 929                 if (rc != 0) {
 930                         CWARN("LNetSetAsync %s failed: %d\n",
 931                               libcfs_id2str(id), rc);
 932                         return rc;
 933                 }
 934
 935                 LNET_LOCK();
 936                 /* NB router list doesn't change in userspace */
 937                 LASSERT (version == the_lnet.ln_routers_version);
 938         }
 939
 940         LNET_UNLOCK();
 941
 942         if (nrtr == 0) {
 943                 CDEBUG(D_NET,
 944                        "No router found, not starting router checker\n");
 945                 return 0;
 946         }
 947
 948         /* at least allow a SENT and a REPLY per router */
 949         if (router_checker_max_eqsize < 2 * nrtr)
 950                 router_checker_max_eqsize = 2 * nrtr;
 951
 952         LASSERT (eqsz > 0);
 953         if (eqsz > router_checker_max_eqsize)
 954                 eqsz = router_checker_max_eqsize;
 955 #endif
 956
 957         LASSERT (the_lnet.ln_rc_state == LNET_RC_STATE_SHUTDOWN);
 958
 959         if (check_routers_before_use &&
 960             dead_router_check_interval <= 0) {
 961                 LCONSOLE_ERROR_MSG(0x10a, "'dead_router_check_interval' must be"
 962                                    " set if 'check_routers_before_use' is set"
 963                                    "\n");
 964                 return -EINVAL;
 965         }
 966
 967         if (!the_lnet.ln_routing &&
 968             live_router_check_interval <= 0 &&
 969             dead_router_check_interval <= 0)
 970                 return 0;
 971
 972 #ifdef __KERNEL__
 973         cfs_init_mutex_locked(&the_lnet.ln_rc_signal);
 974         /* EQ size doesn't matter; the callback is guaranteed to get every
 975          * event */
 976         eqsz = 1;
 977         rc = LNetEQAlloc(eqsz, lnet_router_checker_event,
 978                          &the_lnet.ln_rc_eqh);
 979 #else
 980         rc = LNetEQAlloc(eqsz, LNET_EQ_HANDLER_NONE,
 981                          &the_lnet.ln_rc_eqh);
 982 #endif
 983         if (rc != 0) {
 984                 CERROR("Can't allocate EQ(%d): %d\n", eqsz, rc);
 985                 return -ENOMEM;
 986         }
 987
 988         memset(&md, 0, sizeof(md));
 989         md.user_ptr  = NULL;
 990         md.start     = &pinginfo;
 991         md.length    = sizeof(pinginfo);
 992         md.options   = LNET_MD_TRUNCATE;
 993         md.threshold = LNET_MD_THRESH_INF;
 994         md.eq_handle = the_lnet.ln_rc_eqh;
 995         rc = LNetMDBind(md, LNET_UNLINK, &the_lnet.ln_rc_mdh);
 996         if (rc < 0) {
 997                 CERROR("Can't bind MD: %d\n", rc);
 998                 rc = LNetEQFree(the_lnet.ln_rc_eqh);
 999                 LASSERT (rc == 0);
1000                 return -ENOMEM;
1001         }
1002         LASSERT (rc == 0);
1003
1004         the_lnet.ln_rc_state = LNET_RC_STATE_RUNNING;
1005 #ifdef __KERNEL__
1006         rc = cfs_create_thread(lnet_router_checker, NULL, 0);
1007         if (rc < 0) {
1008                 CERROR("Can't start router checker thread: %d\n", rc);
1009                 the_lnet.ln_rc_state = LNET_RC_STATE_UNLINKING;
1010                 rc = LNetMDUnlink(the_lnet.ln_rc_mdh);
1011                 LASSERT (rc == 0);
1012                 /* block until event callback signals exit */
1013                 cfs_mutex_down(&the_lnet.ln_rc_signal);
1014                 rc = LNetEQFree(the_lnet.ln_rc_eqh);
1015                 LASSERT (rc == 0);
1016                 the_lnet.ln_rc_state = LNET_RC_STATE_SHUTDOWN;
1017                 return -ENOMEM;
1018         }
1019 #endif
1020
1021         if (check_routers_before_use) {
1022                 /* Note that a helpful side-effect of pinging all known routers
1023                  * at startup is that it makes them drop stale connections they
1024                  * may have to a previous instance of me. */
1025                 lnet_wait_known_routerstate();
1026         }
1027
1028         return 0;
1029 }
1030
1031 void
1032 lnet_router_checker_stop (void)
1033 {
1034         int rc;
1035
1036         if (the_lnet.ln_rc_state == LNET_RC_STATE_SHUTDOWN)
1037                 return;
1038
1039         LASSERT (the_lnet.ln_rc_state == LNET_RC_STATE_RUNNING);
1040         the_lnet.ln_rc_state = LNET_RC_STATE_STOPTHREAD;
1041
1042 #ifdef __KERNEL__
1043         /* block until event callback signals exit */
1044         cfs_mutex_down(&the_lnet.ln_rc_signal);
1045 #else
1046         while (the_lnet.ln_rc_state != LNET_RC_STATE_UNLINKED) {
1047                 lnet_router_checker();
1048                 cfs_pause(cfs_time_seconds(1));
1049         }
1050 #endif
1051         LASSERT (the_lnet.ln_rc_state == LNET_RC_STATE_UNLINKED);
1052
1053         rc = LNetEQFree(the_lnet.ln_rc_eqh);
1054         LASSERT (rc == 0);
1055         the_lnet.ln_rc_state = LNET_RC_STATE_SHUTDOWN;
1056         return;
1057 }
1058
1059 #if defined(__KERNEL__) && defined(LNET_ROUTER)
1060
1061 static void
1062 lnet_prune_zombie_rcd (int wait_unlink)
1063 {
1064         lnet_rc_data_t   *rcd;
1065         lnet_rc_data_t   *tmp;
1066         cfs_list_t        free_rcd;
1067         int               i;
1068         __u64             version;
1069
1070         CFS_INIT_LIST_HEAD(&free_rcd);
1071
1072         LNET_LOCK();
1073 rescan:
1074         version = the_lnet.ln_routers_version;
1075         cfs_list_for_each_entry_safe (rcd, tmp, &the_lnet.ln_zombie_rcd,
1076                                       rcd_list) {
1077                 if (LNetHandleIsInvalid(rcd->rcd_mdh)) {
1078                         cfs_list_del(&rcd->rcd_list);
1079                         cfs_list_add(&rcd->rcd_list, &free_rcd);
1080                         continue;
1081                 }
1082
1083                 LNET_UNLOCK();
1084
1085                 LNetMDUnlink(rcd->rcd_mdh);
1086
1087                 LNET_LOCK();
1088                 if (version != the_lnet.ln_routers_version)
1089                         goto rescan;
1090         }
1091
1092         i = 2;
1093         while (wait_unlink && !cfs_list_empty(&the_lnet.ln_zombie_rcd)) {
1094                 rcd = cfs_list_entry(the_lnet.ln_zombie_rcd.next,
1095                                      lnet_rc_data_t, rcd_list);
1096                 if (LNetHandleIsInvalid(rcd->rcd_mdh)) {
1097                         cfs_list_del(&rcd->rcd_list);
1098                         cfs_list_add(&rcd->rcd_list, &free_rcd);
1099                         continue;
1100                 }
1101
1102                 LNET_UNLOCK();
1103
1104                 LNetMDUnlink(rcd->rcd_mdh);
1105
1106                 i++;
1107                 CDEBUG(((i & (-i)) == i) ? D_WARNING : D_NET,
1108                        "Waiting for rc buffers to unlink\n");
1109                 cfs_pause(cfs_time_seconds(1));
1110
1111                 LNET_LOCK();
1112         }
1113
1114         LNET_UNLOCK();
1115
1116         while (!cfs_list_empty(&free_rcd)) {
1117                 rcd = cfs_list_entry(free_rcd.next, lnet_rc_data_t, rcd_list);
1118                 cfs_list_del_init(&rcd->rcd_list);
1119                 lnet_destroy_rc_data(rcd);
1120         }
1121         return;
1122 }
1123
1124 static int
1125 lnet_router_checker(void *arg)
1126 {
1127         int                rc;
1128         lnet_peer_t       *rtr;
1129         cfs_list_t        *entry;
1130         lnet_process_id_t  rtr_id;
1131
1132         cfs_daemonize("router_checker");
1133         cfs_block_allsigs();
1134
1135         rtr_id.pid = LUSTRE_SRV_LNET_PID;
1136
1137         LASSERT (the_lnet.ln_rc_state == LNET_RC_STATE_RUNNING);
1138
1139         while (the_lnet.ln_rc_state == LNET_RC_STATE_RUNNING) {
1140                 __u64 version;
1141
1142                 LNET_LOCK();
1143 rescan:
1144                 version = the_lnet.ln_routers_version;
1145
1146                 cfs_list_for_each (entry, &the_lnet.ln_routers) {
1147                         rtr = cfs_list_entry(entry, lnet_peer_t, lp_rtr_list);
1148                         lnet_ping_router_locked(rtr);
1149
1150                         /* NB dropped lock */
1151                         if (version != the_lnet.ln_routers_version) {
1152                                 /* the routers list has changed */
1153                                 goto rescan;
1154                         }
1155                 }
1156
1157                 LNET_UNLOCK();
1158
1159                 if (the_lnet.ln_routing)
1160                         lnet_update_ni_status();
1161
1162                 lnet_prune_zombie_rcd(0); /* don't wait for UNLINK */
1163
1164                 /* Call cfs_pause() here always adds 1 to load average
1165                  * because kernel counts # active tasks as nr_running
1166                  * + nr_uninterruptible. */
1167                 cfs_schedule_timeout_and_set_state(CFS_TASK_INTERRUPTIBLE,
1168                                                    cfs_time_seconds(1));
1169         }
1170
1171         LNET_LOCK();
1172
1173         cfs_list_for_each (entry, &the_lnet.ln_routers) {
1174                 rtr = cfs_list_entry(entry, lnet_peer_t, lp_rtr_list);
1175
1176                 if (rtr->lp_rcd == NULL)
1177                         continue;
1178
1179                 LASSERT (cfs_list_empty(&rtr->lp_rcd->rcd_list));
1180                 cfs_list_add(&rtr->lp_rcd->rcd_list, &the_lnet.ln_zombie_rcd);
1181                 rtr->lp_rcd = NULL;
1182         }
1183
1184         LNET_UNLOCK();
1185
1186         lnet_prune_zombie_rcd(1); /* wait for UNLINK */
1187
1188         LASSERT (the_lnet.ln_rc_state == LNET_RC_STATE_STOPTHREAD);
1189         the_lnet.ln_rc_state = LNET_RC_STATE_UNLINKING;
1190
1191         rc = LNetMDUnlink(the_lnet.ln_rc_mdh);
1192         LASSERT (rc == 0);
1193
1194         /* The unlink event callback will signal final completion */
1195         return 0;
1196 }
1197
1198 void
1199 lnet_destroy_rtrbuf(lnet_rtrbuf_t *rb, int npages)
1200 {
1201         int sz = offsetof(lnet_rtrbuf_t, rb_kiov[npages]);
1202
1203         while (--npages >= 0)
1204                 cfs_free_page(rb->rb_kiov[npages].kiov_page);
1205
1206         LIBCFS_FREE(rb, sz);
1207 }
1208
1209 lnet_rtrbuf_t *
1210 lnet_new_rtrbuf(lnet_rtrbufpool_t *rbp)
1211 {
1212         int            npages = rbp->rbp_npages;
1213         int            sz = offsetof(lnet_rtrbuf_t, rb_kiov[npages]);
1214         struct page   *page;
1215         lnet_rtrbuf_t *rb;
1216         int            i;
1217
1218         LIBCFS_ALLOC(rb, sz);
1219         if (rb == NULL)
1220                 return NULL;
1221
1222         rb->rb_pool = rbp;
1223
1224         for (i = 0; i < npages; i++) {
1225                 page = cfs_alloc_page(CFS_ALLOC_ZERO | CFS_ALLOC_STD);
1226                 if (page == NULL) {
1227                         while (--i >= 0)
1228                                 cfs_free_page(rb->rb_kiov[i].kiov_page);
1229
1230                         LIBCFS_FREE(rb, sz);
1231                         return NULL;
1232                 }
1233
1234                 rb->rb_kiov[i].kiov_len = CFS_PAGE_SIZE;
1235                 rb->rb_kiov[i].kiov_offset = 0;
1236                 rb->rb_kiov[i].kiov_page = page;
1237         }
1238
1239         return rb;
1240 }
1241
1242 void
1243 lnet_rtrpool_free_bufs(lnet_rtrbufpool_t *rbp)
1244 {
1245         int            npages = rbp->rbp_npages;
1246         int            nbuffers = 0;
1247         lnet_rtrbuf_t *rb;
1248
1249         LASSERT (cfs_list_empty(&rbp->rbp_msgs));
1250         LASSERT (rbp->rbp_credits == rbp->rbp_nbuffers);
1251
1252         while (!cfs_list_empty(&rbp->rbp_bufs)) {
1253                 LASSERT (rbp->rbp_credits > 0);
1254
1255                 rb = cfs_list_entry(rbp->rbp_bufs.next,
1256                                     lnet_rtrbuf_t, rb_list);
1257                 cfs_list_del(&rb->rb_list);
1258                 lnet_destroy_rtrbuf(rb, npages);
1259                 nbuffers++;
1260         }
1261
1262         LASSERT (rbp->rbp_nbuffers == nbuffers);
1263         LASSERT (rbp->rbp_credits == nbuffers);
1264
1265         rbp->rbp_nbuffers = rbp->rbp_credits = 0;
1266 }
1267
1268 int
1269 lnet_rtrpool_alloc_bufs(lnet_rtrbufpool_t *rbp, int nbufs)
1270 {
1271         lnet_rtrbuf_t *rb;
1272         int            i;
1273
1274         if (rbp->rbp_nbuffers != 0) {
1275                 LASSERT (rbp->rbp_nbuffers == nbufs);
1276                 return 0;
1277         }
1278
1279         for (i = 0; i < nbufs; i++) {
1280                 rb = lnet_new_rtrbuf(rbp);
1281
1282                 if (rb == NULL) {
1283                         CERROR("Failed to allocate %d router bufs of %d pages\n",
1284                                nbufs, rbp->rbp_npages);
1285                         return -ENOMEM;
1286                 }
1287
1288                 rbp->rbp_nbuffers++;
1289                 rbp->rbp_credits++;
1290                 rbp->rbp_mincredits++;
1291                 cfs_list_add(&rb->rb_list, &rbp->rbp_bufs);
1292
1293                 /* No allocation "under fire" */
1294                 /* Otherwise we'd need code to schedule blocked msgs etc */
1295                 LASSERT (!the_lnet.ln_routing);
1296         }
1297
1298         LASSERT (rbp->rbp_credits == nbufs);
1299         return 0;
1300 }
1301
1302 void
1303 lnet_rtrpool_init(lnet_rtrbufpool_t *rbp, int npages)
1304 {
1305         CFS_INIT_LIST_HEAD(&rbp->rbp_msgs);
1306         CFS_INIT_LIST_HEAD(&rbp->rbp_bufs);
1307
1308         rbp->rbp_npages = npages;
1309         rbp->rbp_credits = 0;
1310         rbp->rbp_mincredits = 0;
1311 }
1312
1313 void
1314 lnet_free_rtrpools(void)
1315 {
1316         lnet_rtrpool_free_bufs(&the_lnet.ln_rtrpools[0]);
1317         lnet_rtrpool_free_bufs(&the_lnet.ln_rtrpools[1]);
1318         lnet_rtrpool_free_bufs(&the_lnet.ln_rtrpools[2]);
1319 }
1320
1321 void
1322 lnet_init_rtrpools(void)
1323 {
1324         int small_pages = 1;
1325         int large_pages = (LNET_MTU + CFS_PAGE_SIZE - 1) >> CFS_PAGE_SHIFT;
1326
1327         lnet_rtrpool_init(&the_lnet.ln_rtrpools[0], 0);
1328         lnet_rtrpool_init(&the_lnet.ln_rtrpools[1], small_pages);
1329         lnet_rtrpool_init(&the_lnet.ln_rtrpools[2], large_pages);
1330 }
1331
1332
1333 int
1334 lnet_alloc_rtrpools(int im_a_router)
1335 {
1336         int       rc;
1337
1338         if (!strcmp(forwarding, "")) {
1339                 /* not set either way */
1340                 if (!im_a_router)
1341                         return 0;
1342         } else if (!strcmp(forwarding, "disabled")) {
1343                 /* explicitly disabled */
1344                 return 0;
1345         } else if (!strcmp(forwarding, "enabled")) {
1346                 /* explicitly enabled */
1347         } else {
1348                 LCONSOLE_ERROR_MSG(0x10b, "'forwarding' not set to either "
1349                                    "'enabled' or 'disabled'\n");
1350                 return -EINVAL;
1351         }
1352
1353         if (tiny_router_buffers <= 0) {
1354                 LCONSOLE_ERROR_MSG(0x10c, "tiny_router_buffers=%d invalid when "
1355                                    "routing enabled\n", tiny_router_buffers);
1356                 rc = -EINVAL;
1357                 goto failed;
1358         }
1359
1360         rc = lnet_rtrpool_alloc_bufs(&the_lnet.ln_rtrpools[0],
1361                                      tiny_router_buffers);
1362         if (rc != 0)
1363                 goto failed;
1364
1365         if (small_router_buffers <= 0) {
1366                 LCONSOLE_ERROR_MSG(0x10d, "small_router_buffers=%d invalid when"
1367                                    " routing enabled\n", small_router_buffers);
1368                 rc = -EINVAL;
1369                 goto failed;
1370         }
1371
1372         rc = lnet_rtrpool_alloc_bufs(&the_lnet.ln_rtrpools[1],
1373                                      small_router_buffers);
1374         if (rc != 0)
1375                 goto failed;
1376
1377         if (large_router_buffers <= 0) {
1378                 LCONSOLE_ERROR_MSG(0x10e, "large_router_buffers=%d invalid when"
1379                                    " routing enabled\n", large_router_buffers);
1380                 rc = -EINVAL;
1381                 goto failed;
1382         }
1383
1384         rc = lnet_rtrpool_alloc_bufs(&the_lnet.ln_rtrpools[2],
1385                                      large_router_buffers);
1386         if (rc != 0)
1387                 goto failed;
1388
1389         LNET_LOCK();
1390         the_lnet.ln_routing = 1;
1391         LNET_UNLOCK();
1392
1393         return 0;
1394
1395  failed:
1396         lnet_free_rtrpools();
1397         return rc;
1398 }
1399
1400 int
1401 lnet_notify (lnet_ni_t *ni, lnet_nid_t nid, int alive, cfs_time_t when)
1402 {
1403         lnet_peer_t *lp = NULL;
1404         cfs_time_t   now = cfs_time_current();
1405
1406         LASSERT (!cfs_in_interrupt ());
1407
1408         CDEBUG (D_NET, "%s notifying %s: %s\n",
1409                 (ni == NULL) ? "userspace" : libcfs_nid2str(ni->ni_nid),
1410                 libcfs_nid2str(nid),
1411                 alive ? "up" : "down");
1412
1413         if (ni != NULL &&
1414             LNET_NIDNET(ni->ni_nid) != LNET_NIDNET(nid)) {
1415                 CWARN ("Ignoring notification of %s %s by %s (different net)\n",
1416                         libcfs_nid2str(nid), alive ? "birth" : "death",
1417                         libcfs_nid2str(ni->ni_nid));
1418                 return -EINVAL;
1419         }
1420
1421         /* can't do predictions... */
1422         if (cfs_time_after(when, now)) {
1423                 CWARN ("Ignoring prediction from %s of %s %s "
1424                        "%ld seconds in the future\n",
1425                        (ni == NULL) ? "userspace" : libcfs_nid2str(ni->ni_nid),
1426                        libcfs_nid2str(nid), alive ? "up" : "down",
1427                        cfs_duration_sec(cfs_time_sub(when, now)));
1428                 return -EINVAL;
1429         }
1430
1431         if (ni != NULL && !alive &&             /* LND telling me she's down */
1432             !auto_down) {                       /* auto-down disabled */
1433                 CDEBUG(D_NET, "Auto-down disabled\n");
1434                 return 0;
1435         }
1436
1437         LNET_LOCK();
1438
1439         lp = lnet_find_peer_locked(nid);
1440         if (lp == NULL) {
1441                 /* nid not found */
1442                 LNET_UNLOCK();
1443                 CDEBUG(D_NET, "%s not found\n", libcfs_nid2str(nid));
1444                 return 0;
1445         }
1446
1447         /* We can't fully trust LND on reporting exact peer last_alive
1448          * if he notifies us about dead peer. For example ksocklnd can
1449          * call us with when == _time_when_the_node_was_booted_ if
1450          * no connections were successfully established */
1451         if (ni != NULL && !alive && when < lp->lp_last_alive)
1452                 when = lp->lp_last_alive;
1453
1454         lnet_notify_locked(lp, ni == NULL, alive, when);
1455
1456         LNET_UNLOCK();
1457
1458         lnet_do_notify(lp);
1459
1460         LNET_LOCK();
1461
1462         lnet_peer_decref_locked(lp);
1463
1464         LNET_UNLOCK();
1465         return 0;
1466 }
1467 EXPORT_SYMBOL(lnet_notify);
1468
1469 void
1470 lnet_get_tunables (void)
1471 {
1472         return;
1473 }
1474
1475 #else
1476
1477 int
1478 lnet_notify (lnet_ni_t *ni, lnet_nid_t nid, int alive, cfs_time_t when)
1479 {
1480         return -EOPNOTSUPP;
1481 }
1482
1483 void
1484 lnet_router_checker (void)
1485 {
1486         static time_t last = 0;
1487         static int    running = 0;
1488
1489         time_t            now = cfs_time_current_sec();
1490         int               interval = now - last;
1491         int               rc;
1492         __u64             version;
1493         lnet_peer_t      *rtr;
1494
1495         /* It's no use to call me again within a sec - all intervals and
1496          * timeouts are measured in seconds */
1497         if (last != 0 && interval < 2)
1498                 return;
1499
1500         if (last != 0 &&
1501             interval > MAX(live_router_check_interval,
1502                            dead_router_check_interval))
1503                 CNETERR("Checker(%d/%d) not called for %d seconds\n",
1504                         live_router_check_interval, dead_router_check_interval,
1505                         interval);
1506
1507         LNET_LOCK();
1508         LASSERT (!running); /* recursion check */
1509         running = 1;
1510         LNET_UNLOCK();
1511
1512         last = now;
1513
1514         if (the_lnet.ln_rc_state == LNET_RC_STATE_STOPTHREAD) {
1515                 the_lnet.ln_rc_state = LNET_RC_STATE_UNLINKING;
1516                 rc = LNetMDUnlink(the_lnet.ln_rc_mdh);
1517                 LASSERT (rc == 0);
1518         }
1519
1520         /* consume all pending events */
1521         while (1) {
1522                 int          i;
1523                 lnet_event_t ev;
1524
1525                 /* NB ln_rc_eqh must be the 1st in 'eventqs' otherwise the
1526                  * recursion breaker in LNetEQPoll would fail */
1527                 rc = LNetEQPoll(&the_lnet.ln_rc_eqh, 1, 0, &ev, &i);
1528                 if (rc == 0)   /* no event pending */
1529                         break;
1530
1531                 /* NB a lost SENT prevents me from pinging a router again */
1532                 if (rc == -EOVERFLOW) {
1533                         CERROR("Dropped an event!!!\n");
1534                         abort();
1535                 }
1536
1537                 LASSERT (rc == 1);
1538
1539                 LNET_LOCK();
1540                 lnet_router_checker_event(&ev);
1541                 LNET_UNLOCK();
1542         }
1543
1544         if (the_lnet.ln_rc_state == LNET_RC_STATE_UNLINKED ||
1545             the_lnet.ln_rc_state == LNET_RC_STATE_UNLINKING) {
1546                 running = 0;
1547                 return;
1548         }
1549
1550         LASSERT (the_lnet.ln_rc_state == LNET_RC_STATE_RUNNING);
1551
1552         LNET_LOCK();
1553
1554         version = the_lnet.ln_routers_version;
1555         cfs_list_for_each_entry (rtr, &the_lnet.ln_routers, lp_rtr_list) {
1556                 lnet_ping_router_locked(rtr);
1557                 LASSERT (version == the_lnet.ln_routers_version);
1558         }
1559
1560         LNET_UNLOCK();
1561
1562         running = 0; /* lock only needed for the recursion check */
1563         return;
1564 }
1565
1566 /* NB lnet_peers_start_down depends on me,
1567  * so must be called before any peer creation */
1568 void
1569 lnet_get_tunables (void)
1570 {
1571         char *s;
1572
1573         s = getenv("LNET_ROUTER_PING_TIMEOUT");
1574         if (s != NULL) router_ping_timeout = atoi(s);
1575
1576         s = getenv("LNET_LIVE_ROUTER_CHECK_INTERVAL");
1577         if (s != NULL) live_router_check_interval = atoi(s);
1578
1579         s = getenv("LNET_DEAD_ROUTER_CHECK_INTERVAL");
1580         if (s != NULL) dead_router_check_interval = atoi(s);
1581
1582         /* This replaces old lnd_notify mechanism */
1583         check_routers_before_use = 1;
1584         if (dead_router_check_interval <= 0)
1585                 dead_router_check_interval = 30;
1586 }
1587
1588 void
1589 lnet_free_rtrpools (void)
1590 {
1591 }
1592
1593 void
1594 lnet_init_rtrpools (void)
1595 {
1596 }
1597
1598 int
1599 lnet_alloc_rtrpools (int im_a_arouter)
1600 {
1601         return 0;
1602 }
1603
1604 #endif