lnet/lnet/router.c

   1 /*
   2  * Copyright (c) 2007, 2010, Oracle and/or its affiliates. All rights reserved.
   3  *
   4  * Copyright (c) 2011, 2016, Intel Corporation.
   5  *
   6  *   This file is part of Lustre, https://wiki.hpdd.intel.com/
   7  *
   8  *   Portals is free software; you can redistribute it and/or
   9  *   modify it under the terms of version 2 of the GNU General Public
  10  *   License as published by the Free Software Foundation.
  11  *
  12  *   Portals is distributed in the hope that it will be useful,
  13  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  *   GNU General Public License for more details.
  16  *
  17  *   You should have received a copy of the GNU General Public License
  18  *   along with Portals; if not, write to the Free Software
  19  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20  *
  21  */
  22
  23 #define DEBUG_SUBSYSTEM S_LNET
  24 #include <lnet/lib-lnet.h>
  25
  26 #define LNET_NRB_TINY_MIN       512     /* min value for each CPT */
  27 #define LNET_NRB_TINY           (LNET_NRB_TINY_MIN * 4)
  28 #define LNET_NRB_SMALL_MIN      4096    /* min value for each CPT */
  29 #define LNET_NRB_SMALL          (LNET_NRB_SMALL_MIN * 4)
  30 #define LNET_NRB_SMALL_PAGES    1
  31 #define LNET_NRB_LARGE_MIN      256     /* min value for each CPT */
  32 #define LNET_NRB_LARGE          (LNET_NRB_LARGE_MIN * 4)
  33 #define LNET_NRB_LARGE_PAGES    ((LNET_MTU + PAGE_SIZE - 1) >> \
  34                                   PAGE_SHIFT)
  35
  36 static char *forwarding = "";
  37 module_param(forwarding, charp, 0444);
  38 MODULE_PARM_DESC(forwarding, "Explicitly enable/disable forwarding between networks");
  39
  40 static int tiny_router_buffers;
  41 module_param(tiny_router_buffers, int, 0444);
  42 MODULE_PARM_DESC(tiny_router_buffers, "# of 0 payload messages to buffer in the router");
  43 static int small_router_buffers;
  44 module_param(small_router_buffers, int, 0444);
  45 MODULE_PARM_DESC(small_router_buffers, "# of small (1 page) messages to buffer in the router");
  46 static int large_router_buffers;
  47 module_param(large_router_buffers, int, 0444);
  48 MODULE_PARM_DESC(large_router_buffers, "# of large messages to buffer in the router");
  49 static int peer_buffer_credits;
  50 module_param(peer_buffer_credits, int, 0444);
  51 MODULE_PARM_DESC(peer_buffer_credits, "# router buffer credits per peer");
  52
  53 static int auto_down = 1;
  54 module_param(auto_down, int, 0444);
  55 MODULE_PARM_DESC(auto_down, "Automatically mark peers down on comms error");
  56
  57 int
  58 lnet_peer_buffer_credits(struct lnet_net *net)
  59 {
  60         /* NI option overrides LNet default */
  61         if (net->net_tunables.lct_peer_rtr_credits > 0)
  62                 return net->net_tunables.lct_peer_rtr_credits;
  63         if (peer_buffer_credits > 0)
  64                 return peer_buffer_credits;
  65
  66         /* As an approximation, allow this peer the same number of router
  67          * buffers as it is allowed outstanding sends */
  68         return net->net_tunables.lct_peer_tx_credits;
  69 }
  70
  71 /* forward ref's */
  72 static int lnet_router_checker(void *);
  73
  74 static int check_routers_before_use;
  75 module_param(check_routers_before_use, int, 0444);
  76 MODULE_PARM_DESC(check_routers_before_use, "Assume routers are down and ping them before use");
  77
  78 int avoid_asym_router_failure = 1;
  79 module_param(avoid_asym_router_failure, int, 0644);
  80 MODULE_PARM_DESC(avoid_asym_router_failure, "Avoid asymmetrical router failures (0 to disable)");
  81
  82 static int dead_router_check_interval = 60;
  83 module_param(dead_router_check_interval, int, 0644);
  84 MODULE_PARM_DESC(dead_router_check_interval, "Seconds between dead router health checks (<= 0 to disable)");
  85
  86 static int live_router_check_interval = 60;
  87 module_param(live_router_check_interval, int, 0644);
  88 MODULE_PARM_DESC(live_router_check_interval, "Seconds between live router health checks (<= 0 to disable)");
  89
  90 static int router_ping_timeout = 50;
  91 module_param(router_ping_timeout, int, 0644);
  92 MODULE_PARM_DESC(router_ping_timeout, "Seconds to wait for the reply to a router health query");
  93
  94 int
  95 lnet_peers_start_down(void)
  96 {
  97         return check_routers_before_use;
  98 }
  99
 100 void
 101 lnet_notify_locked(struct lnet_peer_ni *lp, int notifylnd, int alive,
 102                    cfs_time_t when)
 103 {
 104         if (cfs_time_before(when, lp->lpni_timestamp)) { /* out of date information */
 105                 CDEBUG(D_NET, "Out of date\n");
 106                 return;
 107         }
 108
 109         lp->lpni_timestamp = when;                /* update timestamp */
 110         lp->lpni_ping_deadline = 0;               /* disable ping timeout */
 111
 112         if (lp->lpni_alive_count != 0 &&          /* got old news */
 113             (!lp->lpni_alive) == (!alive)) {      /* new date for old news */
 114                 CDEBUG(D_NET, "Old news\n");
 115                 return;
 116         }
 117
 118         /* Flag that notification is outstanding */
 119
 120         lp->lpni_alive_count++;
 121         lp->lpni_alive = !(!alive);               /* 1 bit! */
 122         lp->lpni_notify = 1;
 123         lp->lpni_notifylnd |= notifylnd;
 124         if (lp->lpni_alive)
 125                 lp->lpni_ping_feats = LNET_PING_FEAT_INVAL; /* reset */
 126
 127         CDEBUG(D_NET, "set %s %d\n", libcfs_nid2str(lp->lpni_nid), alive);
 128 }
 129
 130 static void
 131 lnet_ni_notify_locked(lnet_ni_t *ni, struct lnet_peer_ni *lp)
 132 {
 133         int        alive;
 134         int        notifylnd;
 135
 136         /* Notify only in 1 thread at any time to ensure ordered notification.
 137          * NB individual events can be missed; the only guarantee is that you
 138          * always get the most recent news */
 139
 140         if (lp->lpni_notifying || ni == NULL)
 141                 return;
 142
 143         lp->lpni_notifying = 1;
 144
 145         while (lp->lpni_notify) {
 146                 alive     = lp->lpni_alive;
 147                 notifylnd = lp->lpni_notifylnd;
 148
 149                 lp->lpni_notifylnd = 0;
 150                 lp->lpni_notify    = 0;
 151
 152                 if (notifylnd && ni->ni_net->net_lnd->lnd_notify != NULL) {
 153                         lnet_net_unlock(lp->lpni_cpt);
 154
 155                         /* A new notification could happen now; I'll handle it
 156                          * when control returns to me */
 157
 158                         (ni->ni_net->net_lnd->lnd_notify)(ni, lp->lpni_nid,
 159                                                           alive);
 160
 161                         lnet_net_lock(lp->lpni_cpt);
 162                 }
 163         }
 164
 165         lp->lpni_notifying = 0;
 166 }
 167
 168
 169 static void
 170 lnet_rtr_addref_locked(struct lnet_peer_ni *lp)
 171 {
 172         LASSERT(atomic_read(&lp->lpni_refcount) > 0);
 173         LASSERT(lp->lpni_rtr_refcount >= 0);
 174
 175         /* lnet_net_lock must be exclusively locked */
 176         lp->lpni_rtr_refcount++;
 177         if (lp->lpni_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                         struct lnet_peer_ni *rtr =
 183                           list_entry(pos, struct lnet_peer_ni,
 184                                      lpni_rtr_list);
 185
 186                         if (rtr->lpni_nid < lp->lpni_nid)
 187                                 break;
 188                 }
 189
 190                 list_add(&lp->lpni_rtr_list, pos);
 191                 /* addref for the_lnet.ln_routers */
 192                 lnet_peer_ni_addref_locked(lp);
 193                 the_lnet.ln_routers_version++;
 194         }
 195 }
 196
 197 static void
 198 lnet_rtr_decref_locked(struct lnet_peer_ni *lp)
 199 {
 200         LASSERT(atomic_read(&lp->lpni_refcount) > 0);
 201         LASSERT(lp->lpni_rtr_refcount > 0);
 202
 203         /* lnet_net_lock must be exclusively locked */
 204         lp->lpni_rtr_refcount--;
 205         if (lp->lpni_rtr_refcount == 0) {
 206                 LASSERT(list_empty(&lp->lpni_routes));
 207
 208                 if (lp->lpni_rcd != NULL) {
 209                         list_add(&lp->lpni_rcd->rcd_list,
 210                                  &the_lnet.ln_rcd_deathrow);
 211                         lp->lpni_rcd = NULL;
 212                 }
 213
 214                 list_del(&lp->lpni_rtr_list);
 215                 /* decref for the_lnet.ln_routers */
 216                 lnet_peer_ni_decref_locked(lp);
 217                 the_lnet.ln_routers_version++;
 218         }
 219 }
 220
 221 lnet_remotenet_t *
 222 lnet_find_rnet_locked(__u32 net)
 223 {
 224         lnet_remotenet_t *rnet;
 225         struct list_head *tmp;
 226         struct list_head *rn_list;
 227
 228         LASSERT(!the_lnet.ln_shutdown);
 229
 230         rn_list = lnet_net2rnethash(net);
 231         list_for_each(tmp, rn_list) {
 232                 rnet = list_entry(tmp, lnet_remotenet_t, lrn_list);
 233
 234                 if (rnet->lrn_net == net)
 235                         return rnet;
 236         }
 237         return NULL;
 238 }
 239
 240 static void lnet_shuffle_seed(void)
 241 {
 242         static int seeded;
 243         __u32 lnd_type;
 244         __u32 seed[2];
 245         struct timespec64 ts;
 246         lnet_ni_t *ni = NULL;
 247
 248         if (seeded)
 249                 return;
 250
 251         cfs_get_random_bytes(seed, sizeof(seed));
 252
 253         /* Nodes with small feet have little entropy
 254          * the NID for this node gives the most entropy in the low bits */
 255         while ((ni = lnet_get_next_ni_locked(NULL, ni))) {
 256                 lnd_type = LNET_NETTYP(LNET_NIDNET(ni->ni_nid));
 257
 258                 if (lnd_type != LOLND)
 259                         seed[0] ^= (LNET_NIDADDR(ni->ni_nid) | lnd_type);
 260         }
 261
 262         ktime_get_ts64(&ts);
 263         cfs_srand(ts.tv_sec ^ seed[0], ts.tv_nsec ^ seed[1]);
 264         seeded = 1;
 265         return;
 266 }
 267
 268 /* NB expects LNET_LOCK held */
 269 static void
 270 lnet_add_route_to_rnet(lnet_remotenet_t *rnet, lnet_route_t *route)
 271 {
 272         unsigned int      len = 0;
 273         unsigned int      offset = 0;
 274         struct list_head *e;
 275
 276         lnet_shuffle_seed();
 277
 278         list_for_each(e, &rnet->lrn_routes) {
 279                 len++;
 280         }
 281
 282         /* len+1 positions to add a new entry, also prevents division by 0 */
 283         offset = cfs_rand() % (len + 1);
 284         list_for_each(e, &rnet->lrn_routes) {
 285                 if (offset == 0)
 286                         break;
 287                 offset--;
 288         }
 289         list_add(&route->lr_list, e);
 290         list_add(&route->lr_gwlist, &route->lr_gateway->lpni_routes);
 291
 292         the_lnet.ln_remote_nets_version++;
 293         lnet_rtr_addref_locked(route->lr_gateway);
 294 }
 295
 296 int
 297 lnet_add_route(__u32 net, __u32 hops, lnet_nid_t gateway,
 298                unsigned int priority)
 299 {
 300         struct list_head        *e;
 301         lnet_remotenet_t        *rnet;
 302         lnet_remotenet_t        *rnet2;
 303         lnet_route_t            *route;
 304         lnet_ni_t               *ni;
 305         struct lnet_peer_ni     *lpni;
 306         int                     add_route;
 307         int                     rc;
 308
 309         CDEBUG(D_NET, "Add route: net %s hops %d priority %u gw %s\n",
 310                libcfs_net2str(net), hops, priority, libcfs_nid2str(gateway));
 311
 312         if (gateway == LNET_NID_ANY ||
 313             LNET_NETTYP(LNET_NIDNET(gateway)) == LOLND ||
 314             net == LNET_NIDNET(LNET_NID_ANY) ||
 315             LNET_NETTYP(net) == LOLND ||
 316             LNET_NIDNET(gateway) == net ||
 317             (hops != LNET_UNDEFINED_HOPS && (hops < 1 || hops > 255)))
 318                 return -EINVAL;
 319
 320         if (lnet_islocalnet(net))       /* it's a local network */
 321                 return -EEXIST;
 322
 323         /* Assume net, route, all new */
 324         LIBCFS_ALLOC(route, sizeof(*route));
 325         LIBCFS_ALLOC(rnet, sizeof(*rnet));
 326         if (route == NULL || rnet == NULL) {
 327                 CERROR("Out of memory creating route %s %d %s\n",
 328                        libcfs_net2str(net), hops, libcfs_nid2str(gateway));
 329                 if (route != NULL)
 330                         LIBCFS_FREE(route, sizeof(*route));
 331                 if (rnet != NULL)
 332                         LIBCFS_FREE(rnet, sizeof(*rnet));
 333                 return -ENOMEM;
 334         }
 335
 336         INIT_LIST_HEAD(&rnet->lrn_routes);
 337         rnet->lrn_net = net;
 338         route->lr_hops = hops;
 339         route->lr_net = net;
 340         route->lr_priority = priority;
 341
 342         lnet_net_lock(LNET_LOCK_EX);
 343
 344         lpni = lnet_nid2peerni_locked(gateway, LNET_LOCK_EX);
 345         if (IS_ERR(lpni)) {
 346                 lnet_net_unlock(LNET_LOCK_EX);
 347
 348                 LIBCFS_FREE(route, sizeof(*route));
 349                 LIBCFS_FREE(rnet, sizeof(*rnet));
 350
 351                 rc = PTR_ERR(lpni);
 352                 if (rc == -EHOSTUNREACH) /* gateway is not on a local net. */
 353                         return rc;       /* ignore the route entry */
 354                 CERROR("Error %d creating route %s %d %s\n", rc,
 355                         libcfs_net2str(net), hops,
 356                         libcfs_nid2str(gateway));
 357                 return rc;
 358         }
 359         route->lr_gateway = lpni;
 360         LASSERT(!the_lnet.ln_shutdown);
 361
 362         rnet2 = lnet_find_rnet_locked(net);
 363         if (rnet2 == NULL) {
 364                 /* new network */
 365                 list_add_tail(&rnet->lrn_list, lnet_net2rnethash(net));
 366                 rnet2 = rnet;
 367         }
 368
 369         /* Search for a duplicate route (it's a NOOP if it is) */
 370         add_route = 1;
 371         list_for_each(e, &rnet2->lrn_routes) {
 372                 lnet_route_t *route2 = list_entry(e, lnet_route_t, lr_list);
 373
 374                 if (route2->lr_gateway == route->lr_gateway) {
 375                         add_route = 0;
 376                         break;
 377                 }
 378
 379                 /* our lookups must be true */
 380                 LASSERT(route2->lr_gateway->lpni_nid != gateway);
 381         }
 382
 383         if (add_route) {
 384                 lnet_peer_ni_addref_locked(route->lr_gateway); /* +1 for notify */
 385                 lnet_add_route_to_rnet(rnet2, route);
 386
 387                 ni = lnet_get_next_ni_locked(route->lr_gateway->lpni_net, NULL);
 388                 lnet_net_unlock(LNET_LOCK_EX);
 389
 390                 /* XXX Assume alive */
 391                 if (ni->ni_net->net_lnd->lnd_notify != NULL)
 392                         (ni->ni_net->net_lnd->lnd_notify)(ni, gateway, 1);
 393
 394                 lnet_net_lock(LNET_LOCK_EX);
 395         }
 396
 397         /* -1 for notify or !add_route */
 398         lnet_peer_ni_decref_locked(route->lr_gateway);
 399         lnet_net_unlock(LNET_LOCK_EX);
 400
 401         rc = 0;
 402
 403         if (!add_route) {
 404                 rc = -EEXIST;
 405                 LIBCFS_FREE(route, sizeof(*route));
 406         }
 407
 408         if (rnet != rnet2)
 409                 LIBCFS_FREE(rnet, sizeof(*rnet));
 410
 411         /* indicate to startup the router checker if configured */
 412         wake_up(&the_lnet.ln_rc_waitq);
 413
 414         return rc;
 415 }
 416
 417 int
 418 lnet_check_routes(void)
 419 {
 420         lnet_remotenet_t *rnet;
 421         lnet_route_t     *route;
 422         lnet_route_t     *route2;
 423         struct list_head *e1;
 424         struct list_head *e2;
 425         int               cpt;
 426         struct list_head *rn_list;
 427         int               i;
 428
 429         cpt = lnet_net_lock_current();
 430
 431         for (i = 0; i < LNET_REMOTE_NETS_HASH_SIZE; i++) {
 432                 rn_list = &the_lnet.ln_remote_nets_hash[i];
 433                 list_for_each(e1, rn_list) {
 434                         rnet = list_entry(e1, lnet_remotenet_t, lrn_list);
 435
 436                         route2 = NULL;
 437                         list_for_each(e2, &rnet->lrn_routes) {
 438                                 lnet_nid_t      nid1;
 439                                 lnet_nid_t      nid2;
 440                                 int             net;
 441
 442                                 route = list_entry(e2, lnet_route_t,
 443                                                    lr_list);
 444
 445                                 if (route2 == NULL) {
 446                                         route2 = route;
 447                                         continue;
 448                                 }
 449
 450                                 if (route->lr_gateway->lpni_net ==
 451                                     route2->lr_gateway->lpni_net)
 452                                         continue;
 453
 454                                 nid1 = route->lr_gateway->lpni_nid;
 455                                 nid2 = route2->lr_gateway->lpni_nid;
 456                                 net = rnet->lrn_net;
 457
 458                                 lnet_net_unlock(cpt);
 459
 460                                 CERROR("Routes to %s via %s and %s not "
 461                                        "supported\n",
 462                                        libcfs_net2str(net),
 463                                        libcfs_nid2str(nid1),
 464                                        libcfs_nid2str(nid2));
 465                                 return -EINVAL;
 466                         }
 467                 }
 468         }
 469
 470         lnet_net_unlock(cpt);
 471         return 0;
 472 }
 473
 474 int
 475 lnet_del_route(__u32 net, lnet_nid_t gw_nid)
 476 {
 477         struct lnet_peer_ni     *gateway;
 478         lnet_remotenet_t        *rnet;
 479         lnet_route_t            *route;
 480         struct list_head        *e1;
 481         struct list_head        *e2;
 482         int                     rc = -ENOENT;
 483         struct list_head        *rn_list;
 484         int                     idx = 0;
 485
 486         CDEBUG(D_NET, "Del route: net %s : gw %s\n",
 487                libcfs_net2str(net), libcfs_nid2str(gw_nid));
 488
 489         /* NB Caller may specify either all routes via the given gateway
 490          * or a specific route entry actual NIDs) */
 491
 492         lnet_net_lock(LNET_LOCK_EX);
 493         if (net == LNET_NIDNET(LNET_NID_ANY))
 494                 rn_list = &the_lnet.ln_remote_nets_hash[0];
 495         else
 496                 rn_list = lnet_net2rnethash(net);
 497
 498 again:
 499         list_for_each(e1, rn_list) {
 500                 rnet = list_entry(e1, lnet_remotenet_t, lrn_list);
 501
 502                 if (!(net == LNET_NIDNET(LNET_NID_ANY) ||
 503                         net == rnet->lrn_net))
 504                         continue;
 505
 506                 list_for_each(e2, &rnet->lrn_routes) {
 507                         route = list_entry(e2, lnet_route_t, lr_list);
 508
 509                         gateway = route->lr_gateway;
 510                         if (!(gw_nid == LNET_NID_ANY ||
 511                               gw_nid == gateway->lpni_nid))
 512                                 continue;
 513
 514                         list_del(&route->lr_list);
 515                         list_del(&route->lr_gwlist);
 516                         the_lnet.ln_remote_nets_version++;
 517
 518                         if (list_empty(&rnet->lrn_routes))
 519                                 list_del(&rnet->lrn_list);
 520                         else
 521                                 rnet = NULL;
 522
 523                         lnet_rtr_decref_locked(gateway);
 524                         lnet_peer_ni_decref_locked(gateway);
 525
 526                         lnet_net_unlock(LNET_LOCK_EX);
 527
 528                         LIBCFS_FREE(route, sizeof(*route));
 529
 530                         if (rnet != NULL)
 531                                 LIBCFS_FREE(rnet, sizeof(*rnet));
 532
 533                         rc = 0;
 534                         lnet_net_lock(LNET_LOCK_EX);
 535                         goto again;
 536                 }
 537         }
 538
 539         if (net == LNET_NIDNET(LNET_NID_ANY) &&
 540             ++idx < LNET_REMOTE_NETS_HASH_SIZE) {
 541                 rn_list = &the_lnet.ln_remote_nets_hash[idx];
 542                 goto again;
 543         }
 544         lnet_net_unlock(LNET_LOCK_EX);
 545
 546         return rc;
 547 }
 548
 549 void
 550 lnet_destroy_routes (void)
 551 {
 552         lnet_del_route(LNET_NIDNET(LNET_NID_ANY), LNET_NID_ANY);
 553 }
 554
 555 int lnet_get_rtr_pool_cfg(int idx, struct lnet_ioctl_pool_cfg *pool_cfg)
 556 {
 557         int i, rc = -ENOENT, j;
 558
 559         if (the_lnet.ln_rtrpools == NULL)
 560                 return rc;
 561
 562         for (i = 0; i < LNET_NRBPOOLS; i++) {
 563                 lnet_rtrbufpool_t *rbp;
 564
 565                 lnet_net_lock(LNET_LOCK_EX);
 566                 cfs_percpt_for_each(rbp, j, the_lnet.ln_rtrpools) {
 567                         if (i++ != idx)
 568                                 continue;
 569
 570                         pool_cfg->pl_pools[i].pl_npages = rbp[i].rbp_npages;
 571                         pool_cfg->pl_pools[i].pl_nbuffers = rbp[i].rbp_nbuffers;
 572                         pool_cfg->pl_pools[i].pl_credits = rbp[i].rbp_credits;
 573                         pool_cfg->pl_pools[i].pl_mincredits = rbp[i].rbp_mincredits;
 574                         rc = 0;
 575                         break;
 576                 }
 577                 lnet_net_unlock(LNET_LOCK_EX);
 578         }
 579
 580         lnet_net_lock(LNET_LOCK_EX);
 581         pool_cfg->pl_routing = the_lnet.ln_routing;
 582         lnet_net_unlock(LNET_LOCK_EX);
 583
 584         return rc;
 585 }
 586
 587 int
 588 lnet_get_route(int idx, __u32 *net, __u32 *hops,
 589                lnet_nid_t *gateway, __u32 *alive, __u32 *priority)
 590 {
 591         struct list_head *e1;
 592         struct list_head *e2;
 593         lnet_remotenet_t *rnet;
 594         lnet_route_t     *route;
 595         int               cpt;
 596         int               i;
 597         struct list_head *rn_list;
 598
 599         cpt = lnet_net_lock_current();
 600
 601         for (i = 0; i < LNET_REMOTE_NETS_HASH_SIZE; i++) {
 602                 rn_list = &the_lnet.ln_remote_nets_hash[i];
 603                 list_for_each(e1, rn_list) {
 604                         rnet = list_entry(e1, lnet_remotenet_t, lrn_list);
 605
 606                         list_for_each(e2, &rnet->lrn_routes) {
 607                                 route = list_entry(e2, lnet_route_t,
 608                                                    lr_list);
 609
 610                                 if (idx-- == 0) {
 611                                         *net      = rnet->lrn_net;
 612                                         *hops     = route->lr_hops;
 613                                         *priority = route->lr_priority;
 614                                         *gateway  = route->lr_gateway->lpni_nid;
 615                                         *alive    = lnet_is_route_alive(route);
 616                                         lnet_net_unlock(cpt);
 617                                         return 0;
 618                                 }
 619                         }
 620                 }
 621         }
 622
 623         lnet_net_unlock(cpt);
 624         return -ENOENT;
 625 }
 626
 627 void
 628 lnet_swap_pinginfo(struct lnet_ping_info *info)
 629 {
 630         int               i;
 631         struct lnet_ni_status *stat;
 632
 633         __swab32s(&info->pi_magic);
 634         __swab32s(&info->pi_features);
 635         __swab32s(&info->pi_pid);
 636         __swab32s(&info->pi_nnis);
 637         for (i = 0; i < info->pi_nnis && i < LNET_MAX_RTR_NIS; i++) {
 638                 stat = &info->pi_ni[i];
 639                 __swab64s(&stat->ns_nid);
 640                 __swab32s(&stat->ns_status);
 641         }
 642         return;
 643 }
 644
 645 /**
 646  * parse router-checker pinginfo, record number of down NIs for remote
 647  * networks on that router.
 648  */
 649 static void
 650 lnet_parse_rc_info(lnet_rc_data_t *rcd)
 651 {
 652         struct lnet_ping_info   *info = rcd->rcd_pinginfo;
 653         struct lnet_peer_ni     *gw   = rcd->rcd_gateway;
 654         lnet_route_t            *rte;
 655
 656         if (!gw->lpni_alive)
 657                 return;
 658
 659         if (info->pi_magic == __swab32(LNET_PROTO_PING_MAGIC))
 660                 lnet_swap_pinginfo(info);
 661
 662         /* NB always racing with network! */
 663         if (info->pi_magic != LNET_PROTO_PING_MAGIC) {
 664                 CDEBUG(D_NET, "%s: Unexpected magic %08x\n",
 665                        libcfs_nid2str(gw->lpni_nid), info->pi_magic);
 666                 gw->lpni_ping_feats = LNET_PING_FEAT_INVAL;
 667                 return;
 668         }
 669
 670         gw->lpni_ping_feats = info->pi_features;
 671         if ((gw->lpni_ping_feats & LNET_PING_FEAT_MASK) == 0) {
 672                 CDEBUG(D_NET, "%s: Unexpected features 0x%x\n",
 673                        libcfs_nid2str(gw->lpni_nid), gw->lpni_ping_feats);
 674                 return; /* nothing I can understand */
 675         }
 676
 677         if ((gw->lpni_ping_feats & LNET_PING_FEAT_NI_STATUS) == 0)
 678                 return; /* can't carry NI status info */
 679
 680         list_for_each_entry(rte, &gw->lpni_routes, lr_gwlist) {
 681                 int     down = 0;
 682                 int     up = 0;
 683                 int     i;
 684
 685                 if ((gw->lpni_ping_feats & LNET_PING_FEAT_RTE_DISABLED) != 0) {
 686                         rte->lr_downis = 1;
 687                         continue;
 688                 }
 689
 690                 for (i = 0; i < info->pi_nnis && i < LNET_MAX_RTR_NIS; i++) {
 691                         struct lnet_ni_status *stat = &info->pi_ni[i];
 692                         lnet_nid_t       nid = stat->ns_nid;
 693
 694                         if (nid == LNET_NID_ANY) {
 695                                 CDEBUG(D_NET, "%s: unexpected LNET_NID_ANY\n",
 696                                        libcfs_nid2str(gw->lpni_nid));
 697                                 gw->lpni_ping_feats = LNET_PING_FEAT_INVAL;
 698                                 return;
 699                         }
 700
 701                         if (LNET_NETTYP(LNET_NIDNET(nid)) == LOLND)
 702                                 continue;
 703
 704                         if (stat->ns_status == LNET_NI_STATUS_DOWN) {
 705                                 down++;
 706                                 continue;
 707                         }
 708
 709                         if (stat->ns_status == LNET_NI_STATUS_UP) {
 710                                 if (LNET_NIDNET(nid) == rte->lr_net) {
 711                                         up = 1;
 712                                         break;
 713                                 }
 714                                 continue;
 715                         }
 716
 717                         CDEBUG(D_NET, "%s: Unexpected status 0x%x\n",
 718                                libcfs_nid2str(gw->lpni_nid), stat->ns_status);
 719                         gw->lpni_ping_feats = LNET_PING_FEAT_INVAL;
 720                         return;
 721                 }
 722
 723                 if (up) { /* ignore downed NIs if NI for dest network is up */
 724                         rte->lr_downis = 0;
 725                         continue;
 726                 }
 727                 /* if @down is zero and this route is single-hop, it means
 728                  * we can't find NI for target network */
 729                 if (down == 0 && rte->lr_hops == 1)
 730                         down = 1;
 731
 732                 rte->lr_downis = down;
 733         }
 734 }
 735
 736 static void
 737 lnet_router_checker_event(lnet_event_t *event)
 738 {
 739         lnet_rc_data_t          *rcd = event->md.user_ptr;
 740         struct lnet_peer_ni     *lp;
 741
 742         LASSERT(rcd != NULL);
 743
 744         if (event->unlinked) {
 745                 LNetInvalidateHandle(&rcd->rcd_mdh);
 746                 return;
 747         }
 748
 749         LASSERT(event->type == LNET_EVENT_SEND ||
 750                 event->type == LNET_EVENT_REPLY);
 751
 752         lp = rcd->rcd_gateway;
 753         LASSERT(lp != NULL);
 754
 755          /* NB: it's called with holding lnet_res_lock, we have a few
 756           * places need to hold both locks at the same time, please take
 757           * care of lock ordering */
 758         lnet_net_lock(lp->lpni_cpt);
 759         if (!lnet_isrouter(lp) || lp->lpni_rcd != rcd) {
 760                 /* ignore if no longer a router or rcd is replaced */
 761                 goto out;
 762         }
 763
 764         if (event->type == LNET_EVENT_SEND) {
 765                 lp->lpni_ping_notsent = 0;
 766                 if (event->status == 0)
 767                         goto out;
 768         }
 769
 770         /* LNET_EVENT_REPLY */
 771         /* A successful REPLY means the router is up.  If _any_ comms
 772          * to the router fail I assume it's down (this will happen if
 773          * we ping alive routers to try to detect router death before
 774          * apps get burned). */
 775
 776         lnet_notify_locked(lp, 1, (event->status == 0), cfs_time_current());
 777         /* The router checker will wake up very shortly and do the
 778          * actual notification.
 779          * XXX If 'lp' stops being a router before then, it will still
 780          * have the notification pending!!! */
 781
 782         if (avoid_asym_router_failure && event->status == 0)
 783                 lnet_parse_rc_info(rcd);
 784
 785  out:
 786         lnet_net_unlock(lp->lpni_cpt);
 787 }
 788
 789 static void
 790 lnet_wait_known_routerstate(void)
 791 {
 792         struct lnet_peer_ni *rtr;
 793         struct list_head *entry;
 794         int all_known;
 795
 796         LASSERT(the_lnet.ln_rc_state == LNET_RC_STATE_RUNNING);
 797
 798         for (;;) {
 799                 int cpt = lnet_net_lock_current();
 800
 801                 all_known = 1;
 802                 list_for_each(entry, &the_lnet.ln_routers) {
 803                         rtr = list_entry(entry, struct lnet_peer_ni,
 804                                          lpni_rtr_list);
 805
 806                         if (rtr->lpni_alive_count == 0) {
 807                                 all_known = 0;
 808                                 break;
 809                         }
 810                 }
 811
 812                 lnet_net_unlock(cpt);
 813
 814                 if (all_known)
 815                         return;
 816
 817                 set_current_state(TASK_UNINTERRUPTIBLE);
 818                 schedule_timeout(cfs_time_seconds(1));
 819         }
 820 }
 821
 822 void
 823 lnet_router_ni_update_locked(struct lnet_peer_ni *gw, __u32 net)
 824 {
 825         lnet_route_t *rte;
 826
 827         if ((gw->lpni_ping_feats & LNET_PING_FEAT_NI_STATUS) != 0) {
 828                 list_for_each_entry(rte, &gw->lpni_routes, lr_gwlist) {
 829                         if (rte->lr_net == net) {
 830                                 rte->lr_downis = 0;
 831                                 break;
 832                         }
 833                 }
 834         }
 835 }
 836
 837 static void
 838 lnet_update_ni_status_locked(void)
 839 {
 840         lnet_ni_t       *ni = NULL;
 841         time64_t        now;
 842         int             timeout;
 843
 844         LASSERT(the_lnet.ln_routing);
 845
 846         timeout = router_ping_timeout +
 847                   MAX(live_router_check_interval, dead_router_check_interval);
 848
 849         now = ktime_get_real_seconds();
 850         while ((ni = lnet_get_next_ni_locked(NULL, ni))) {
 851                 if (ni->ni_net->net_lnd->lnd_type == LOLND)
 852                         continue;
 853
 854                 if (now < ni->ni_last_alive + timeout)
 855                         continue;
 856
 857                 lnet_ni_lock(ni);
 858                 /* re-check with lock */
 859                 if (now < ni->ni_last_alive + timeout) {
 860                         lnet_ni_unlock(ni);
 861                         continue;
 862                 }
 863
 864                 LASSERT(ni->ni_status != NULL);
 865
 866                 if (ni->ni_status->ns_status != LNET_NI_STATUS_DOWN) {
 867                         CDEBUG(D_NET, "NI(%s:%d) status changed to down\n",
 868                                libcfs_nid2str(ni->ni_nid), timeout);
 869                         /* NB: so far, this is the only place to set
 870                          * NI status to "down" */
 871                         ni->ni_status->ns_status = LNET_NI_STATUS_DOWN;
 872                 }
 873                 lnet_ni_unlock(ni);
 874         }
 875 }
 876
 877 static void
 878 lnet_destroy_rc_data(lnet_rc_data_t *rcd)
 879 {
 880         LASSERT(list_empty(&rcd->rcd_list));
 881         /* detached from network */
 882         LASSERT(LNetHandleIsInvalid(rcd->rcd_mdh));
 883
 884         if (rcd->rcd_gateway != NULL) {
 885                 int cpt = rcd->rcd_gateway->lpni_cpt;
 886
 887                 lnet_net_lock(cpt);
 888                 lnet_peer_ni_decref_locked(rcd->rcd_gateway);
 889                 lnet_net_unlock(cpt);
 890         }
 891
 892         if (rcd->rcd_pinginfo != NULL)
 893                 LIBCFS_FREE(rcd->rcd_pinginfo, LNET_PINGINFO_SIZE);
 894
 895         LIBCFS_FREE(rcd, sizeof(*rcd));
 896 }
 897
 898 static lnet_rc_data_t *
 899 lnet_create_rc_data_locked(struct lnet_peer_ni *gateway)
 900 {
 901         lnet_rc_data_t          *rcd = NULL;
 902         struct lnet_ping_info   *pi;
 903         int                     rc;
 904         int                     i;
 905
 906         lnet_net_unlock(gateway->lpni_cpt);
 907
 908         LIBCFS_ALLOC(rcd, sizeof(*rcd));
 909         if (rcd == NULL)
 910                 goto out;
 911
 912         LNetInvalidateHandle(&rcd->rcd_mdh);
 913         INIT_LIST_HEAD(&rcd->rcd_list);
 914
 915         LIBCFS_ALLOC(pi, LNET_PINGINFO_SIZE);
 916         if (pi == NULL)
 917                 goto out;
 918
 919         for (i = 0; i < LNET_MAX_RTR_NIS; i++) {
 920                 pi->pi_ni[i].ns_nid = LNET_NID_ANY;
 921                 pi->pi_ni[i].ns_status = LNET_NI_STATUS_INVALID;
 922         }
 923         rcd->rcd_pinginfo = pi;
 924
 925         LASSERT(!LNetHandleIsInvalid(the_lnet.ln_rc_eqh));
 926         rc = LNetMDBind((lnet_md_t){.start     = pi,
 927                                     .user_ptr  = rcd,
 928                                     .length    = LNET_PINGINFO_SIZE,
 929                                     .threshold = LNET_MD_THRESH_INF,
 930                                     .options   = LNET_MD_TRUNCATE,
 931                                     .eq_handle = the_lnet.ln_rc_eqh},
 932                         LNET_UNLINK,
 933                         &rcd->rcd_mdh);
 934         if (rc < 0) {
 935                 CERROR("Can't bind MD: %d\n", rc);
 936                 goto out;
 937         }
 938         LASSERT(rc == 0);
 939
 940         lnet_net_lock(gateway->lpni_cpt);
 941         /* router table changed or someone has created rcd for this gateway */
 942         if (!lnet_isrouter(gateway) || gateway->lpni_rcd != NULL) {
 943                 lnet_net_unlock(gateway->lpni_cpt);
 944                 goto out;
 945         }
 946
 947         lnet_peer_ni_addref_locked(gateway);
 948         rcd->rcd_gateway = gateway;
 949         gateway->lpni_rcd = rcd;
 950         gateway->lpni_ping_notsent = 0;
 951
 952         return rcd;
 953
 954 out:
 955         if (rcd != NULL) {
 956                 if (!LNetHandleIsInvalid(rcd->rcd_mdh)) {
 957                         rc = LNetMDUnlink(rcd->rcd_mdh);
 958                         LASSERT(rc == 0);
 959                 }
 960                 lnet_destroy_rc_data(rcd);
 961         }
 962
 963         lnet_net_lock(gateway->lpni_cpt);
 964         return gateway->lpni_rcd;
 965 }
 966
 967 static int
 968 lnet_router_check_interval (struct lnet_peer_ni *rtr)
 969 {
 970         int secs;
 971
 972         secs = rtr->lpni_alive ? live_router_check_interval :
 973                                dead_router_check_interval;
 974         if (secs < 0)
 975                 secs = 0;
 976
 977         return secs;
 978 }
 979
 980 static void
 981 lnet_ping_router_locked (struct lnet_peer_ni *rtr)
 982 {
 983         lnet_rc_data_t *rcd = NULL;
 984         cfs_time_t      now = cfs_time_current();
 985         int             secs;
 986         struct lnet_ni  *ni;
 987
 988         lnet_peer_ni_addref_locked(rtr);
 989
 990         if (rtr->lpni_ping_deadline != 0 && /* ping timed out? */
 991             cfs_time_after(now, rtr->lpni_ping_deadline))
 992                 lnet_notify_locked(rtr, 1, 0, now);
 993
 994         /* Run any outstanding notifications */
 995         ni = lnet_get_next_ni_locked(rtr->lpni_net, NULL);
 996         lnet_ni_notify_locked(ni, rtr);
 997
 998         if (!lnet_isrouter(rtr) ||
 999             the_lnet.ln_rc_state != LNET_RC_STATE_RUNNING) {
1000                 /* router table changed or router checker is shutting down */
1001                 lnet_peer_ni_decref_locked(rtr);
1002                 return;
1003         }
1004
1005         rcd = rtr->lpni_rcd != NULL ?
1006               rtr->lpni_rcd : lnet_create_rc_data_locked(rtr);
1007
1008         if (rcd == NULL)
1009                 return;
1010
1011         secs = lnet_router_check_interval(rtr);
1012
1013         CDEBUG(D_NET,
1014                "rtr %s %d: deadline %lu ping_notsent %d alive %d "
1015                "alive_count %d lpni_ping_timestamp %lu\n",
1016                libcfs_nid2str(rtr->lpni_nid), secs,
1017                rtr->lpni_ping_deadline, rtr->lpni_ping_notsent,
1018                rtr->lpni_alive, rtr->lpni_alive_count, rtr->lpni_ping_timestamp);
1019
1020         if (secs != 0 && !rtr->lpni_ping_notsent &&
1021             cfs_time_after(now, cfs_time_add(rtr->lpni_ping_timestamp,
1022                                              cfs_time_seconds(secs)))) {
1023                 int               rc;
1024                 lnet_process_id_t id;
1025                 lnet_handle_md_t  mdh;
1026
1027                 id.nid = rtr->lpni_nid;
1028                 id.pid = LNET_PID_LUSTRE;
1029                 CDEBUG(D_NET, "Check: %s\n", libcfs_id2str(id));
1030
1031                 rtr->lpni_ping_notsent   = 1;
1032                 rtr->lpni_ping_timestamp = now;
1033
1034                 mdh = rcd->rcd_mdh;
1035
1036                 if (rtr->lpni_ping_deadline == 0) {
1037                         rtr->lpni_ping_deadline =
1038                                 cfs_time_shift(router_ping_timeout);
1039                 }
1040
1041                 lnet_net_unlock(rtr->lpni_cpt);
1042
1043                 rc = LNetGet(LNET_NID_ANY, mdh, id, LNET_RESERVED_PORTAL,
1044                              LNET_PROTO_PING_MATCHBITS, 0);
1045
1046                 lnet_net_lock(rtr->lpni_cpt);
1047                 if (rc != 0)
1048                         rtr->lpni_ping_notsent = 0; /* no event pending */
1049         }
1050
1051         lnet_peer_ni_decref_locked(rtr);
1052         return;
1053 }
1054
1055 int
1056 lnet_router_checker_start(void)
1057 {
1058         int                     rc;
1059         int                     eqsz = 0;
1060         struct task_struct     *task;
1061
1062         LASSERT(the_lnet.ln_rc_state == LNET_RC_STATE_SHUTDOWN);
1063
1064         if (check_routers_before_use &&
1065             dead_router_check_interval <= 0) {
1066                 LCONSOLE_ERROR_MSG(0x10a, "'dead_router_check_interval' must be"
1067                                    " set if 'check_routers_before_use' is set"
1068                                    "\n");
1069                 return -EINVAL;
1070         }
1071
1072         sema_init(&the_lnet.ln_rc_signal, 0);
1073
1074         rc = LNetEQAlloc(0, lnet_router_checker_event, &the_lnet.ln_rc_eqh);
1075         if (rc != 0) {
1076                 CERROR("Can't allocate EQ(%d): %d\n", eqsz, rc);
1077                 return -ENOMEM;
1078         }
1079
1080         the_lnet.ln_rc_state = LNET_RC_STATE_RUNNING;
1081         task = kthread_run(lnet_router_checker, NULL, "router_checker");
1082         if (IS_ERR(task)) {
1083                 rc = PTR_ERR(task);
1084                 CERROR("Can't start router checker thread: %d\n", rc);
1085                 /* block until event callback signals exit */
1086                 down(&the_lnet.ln_rc_signal);
1087                 rc = LNetEQFree(the_lnet.ln_rc_eqh);
1088                 LASSERT(rc == 0);
1089                 the_lnet.ln_rc_state = LNET_RC_STATE_SHUTDOWN;
1090                 return -ENOMEM;
1091         }
1092
1093         if (check_routers_before_use) {
1094                 /* Note that a helpful side-effect of pinging all known routers
1095                  * at startup is that it makes them drop stale connections they
1096                  * may have to a previous instance of me. */
1097                 lnet_wait_known_routerstate();
1098         }
1099
1100         return 0;
1101 }
1102
1103 void
1104 lnet_router_checker_stop (void)
1105 {
1106         int rc;
1107
1108         if (the_lnet.ln_rc_state == LNET_RC_STATE_SHUTDOWN)
1109                 return;
1110
1111         LASSERT (the_lnet.ln_rc_state == LNET_RC_STATE_RUNNING);
1112         the_lnet.ln_rc_state = LNET_RC_STATE_STOPPING;
1113         /* wakeup the RC thread if it's sleeping */
1114         wake_up(&the_lnet.ln_rc_waitq);
1115
1116         /* block until event callback signals exit */
1117         down(&the_lnet.ln_rc_signal);
1118         LASSERT(the_lnet.ln_rc_state == LNET_RC_STATE_SHUTDOWN);
1119
1120         rc = LNetEQFree(the_lnet.ln_rc_eqh);
1121         LASSERT(rc == 0);
1122         return;
1123 }
1124
1125 static void
1126 lnet_prune_rc_data(int wait_unlink)
1127 {
1128         lnet_rc_data_t          *rcd;
1129         lnet_rc_data_t          *tmp;
1130         struct lnet_peer_ni     *lp;
1131         struct list_head         head;
1132         int                      i = 2;
1133
1134         if (likely(the_lnet.ln_rc_state == LNET_RC_STATE_RUNNING &&
1135                    list_empty(&the_lnet.ln_rcd_deathrow) &&
1136                    list_empty(&the_lnet.ln_rcd_zombie)))
1137                 return;
1138
1139         INIT_LIST_HEAD(&head);
1140
1141         lnet_net_lock(LNET_LOCK_EX);
1142
1143         if (the_lnet.ln_rc_state != LNET_RC_STATE_RUNNING) {
1144                 /* router checker is stopping, prune all */
1145                 list_for_each_entry(lp, &the_lnet.ln_routers,
1146                                     lpni_rtr_list) {
1147                         if (lp->lpni_rcd == NULL)
1148                                 continue;
1149
1150                         LASSERT(list_empty(&lp->lpni_rcd->rcd_list));
1151                         list_add(&lp->lpni_rcd->rcd_list,
1152                                  &the_lnet.ln_rcd_deathrow);
1153                         lp->lpni_rcd = NULL;
1154                 }
1155         }
1156
1157         /* unlink all RCDs on deathrow list */
1158         list_splice_init(&the_lnet.ln_rcd_deathrow, &head);
1159
1160         if (!list_empty(&head)) {
1161                 lnet_net_unlock(LNET_LOCK_EX);
1162
1163                 list_for_each_entry(rcd, &head, rcd_list)
1164                         LNetMDUnlink(rcd->rcd_mdh);
1165
1166                 lnet_net_lock(LNET_LOCK_EX);
1167         }
1168
1169         list_splice_init(&head, &the_lnet.ln_rcd_zombie);
1170
1171         /* release all zombie RCDs */
1172         while (!list_empty(&the_lnet.ln_rcd_zombie)) {
1173                 list_for_each_entry_safe(rcd, tmp, &the_lnet.ln_rcd_zombie,
1174                                          rcd_list) {
1175                         if (LNetHandleIsInvalid(rcd->rcd_mdh))
1176                                 list_move(&rcd->rcd_list, &head);
1177                 }
1178
1179                 wait_unlink = wait_unlink &&
1180                               !list_empty(&the_lnet.ln_rcd_zombie);
1181
1182                 lnet_net_unlock(LNET_LOCK_EX);
1183
1184                 while (!list_empty(&head)) {
1185                         rcd = list_entry(head.next,
1186                                          lnet_rc_data_t, rcd_list);
1187                         list_del_init(&rcd->rcd_list);
1188                         lnet_destroy_rc_data(rcd);
1189                 }
1190
1191                 if (!wait_unlink)
1192                         return;
1193
1194                 i++;
1195                 CDEBUG(((i & (-i)) == i) ? D_WARNING : D_NET,
1196                        "Waiting for rc buffers to unlink\n");
1197                 set_current_state(TASK_UNINTERRUPTIBLE);
1198                 schedule_timeout(cfs_time_seconds(1) / 4);
1199
1200                 lnet_net_lock(LNET_LOCK_EX);
1201         }
1202
1203         lnet_net_unlock(LNET_LOCK_EX);
1204 }
1205
1206 /*
1207  * This function is called to check if the RC should block indefinitely.
1208  * It's called from lnet_router_checker() as well as being passed to
1209  * wait_event_interruptible() to avoid the lost wake_up problem.
1210  *
1211  * When it's called from wait_event_interruptible() it is necessary to
1212  * also not sleep if the rc state is not running to avoid a deadlock
1213  * when the system is shutting down
1214  */
1215 static inline bool
1216 lnet_router_checker_active(void)
1217 {
1218         if (the_lnet.ln_rc_state != LNET_RC_STATE_RUNNING)
1219                 return true;
1220
1221         /* Router Checker thread needs to run when routing is enabled in
1222          * order to call lnet_update_ni_status_locked() */
1223         if (the_lnet.ln_routing)
1224                 return true;
1225
1226         return !list_empty(&the_lnet.ln_routers) &&
1227                 (live_router_check_interval > 0 ||
1228                  dead_router_check_interval > 0);
1229 }
1230
1231 static int
1232 lnet_router_checker(void *arg)
1233 {
1234         struct lnet_peer_ni *rtr;
1235         struct list_head *entry;
1236
1237         cfs_block_allsigs();
1238
1239         while (the_lnet.ln_rc_state == LNET_RC_STATE_RUNNING) {
1240                 __u64   version;
1241                 int     cpt;
1242                 int     cpt2;
1243
1244                 cpt = lnet_net_lock_current();
1245 rescan:
1246                 version = the_lnet.ln_routers_version;
1247
1248                 list_for_each(entry, &the_lnet.ln_routers) {
1249                         rtr = list_entry(entry, struct lnet_peer_ni,
1250                                          lpni_rtr_list);
1251
1252                         cpt2 = rtr->lpni_cpt;
1253                         if (cpt != cpt2) {
1254                                 lnet_net_unlock(cpt);
1255                                 cpt = cpt2;
1256                                 lnet_net_lock(cpt);
1257                                 /* the routers list has changed */
1258                                 if (version != the_lnet.ln_routers_version)
1259                                         goto rescan;
1260                         }
1261
1262                         lnet_ping_router_locked(rtr);
1263
1264                         /* NB dropped lock */
1265                         if (version != the_lnet.ln_routers_version) {
1266                                 /* the routers list has changed */
1267                                 goto rescan;
1268                         }
1269                 }
1270
1271                 if (the_lnet.ln_routing)
1272                         lnet_update_ni_status_locked();
1273
1274                 lnet_net_unlock(cpt);
1275
1276                 lnet_prune_rc_data(0); /* don't wait for UNLINK */
1277
1278                 /* Call schedule_timeout() here always adds 1 to load average
1279                  * because kernel counts # active tasks as nr_running
1280                  * + nr_uninterruptible. */
1281                 /* if there are any routes then wakeup every second.  If
1282                  * there are no routes then sleep indefinitely until woken
1283                  * up by a user adding a route */
1284                 if (!lnet_router_checker_active())
1285                         wait_event_interruptible(the_lnet.ln_rc_waitq,
1286                                                  lnet_router_checker_active());
1287                 else
1288                         wait_event_interruptible_timeout(the_lnet.ln_rc_waitq,
1289                                                          false,
1290                                                          cfs_time_seconds(1));
1291         }
1292
1293         lnet_prune_rc_data(1); /* wait for UNLINK */
1294
1295         the_lnet.ln_rc_state = LNET_RC_STATE_SHUTDOWN;
1296         up(&the_lnet.ln_rc_signal);
1297         /* The unlink event callback will signal final completion */
1298         return 0;
1299 }
1300
1301 void
1302 lnet_destroy_rtrbuf(lnet_rtrbuf_t *rb, int npages)
1303 {
1304         int sz = offsetof(lnet_rtrbuf_t, rb_kiov[npages]);
1305
1306         while (--npages >= 0)
1307                 __free_page(rb->rb_kiov[npages].kiov_page);
1308
1309         LIBCFS_FREE(rb, sz);
1310 }
1311
1312 static lnet_rtrbuf_t *
1313 lnet_new_rtrbuf(lnet_rtrbufpool_t *rbp, int cpt)
1314 {
1315         int            npages = rbp->rbp_npages;
1316         int            sz = offsetof(lnet_rtrbuf_t, rb_kiov[npages]);
1317         struct page   *page;
1318         lnet_rtrbuf_t *rb;
1319         int            i;
1320
1321         LIBCFS_CPT_ALLOC(rb, lnet_cpt_table(), cpt, sz);
1322         if (rb == NULL)
1323                 return NULL;
1324
1325         rb->rb_pool = rbp;
1326
1327         for (i = 0; i < npages; i++) {
1328                 page = cfs_page_cpt_alloc(lnet_cpt_table(), cpt,
1329                                           GFP_KERNEL | __GFP_ZERO);
1330                 if (page == NULL) {
1331                         while (--i >= 0)
1332                                 __free_page(rb->rb_kiov[i].kiov_page);
1333
1334                         LIBCFS_FREE(rb, sz);
1335                         return NULL;
1336                 }
1337
1338                 rb->rb_kiov[i].kiov_len = PAGE_SIZE;
1339                 rb->rb_kiov[i].kiov_offset = 0;
1340                 rb->rb_kiov[i].kiov_page = page;
1341         }
1342
1343         return rb;
1344 }
1345
1346 static void
1347 lnet_rtrpool_free_bufs(lnet_rtrbufpool_t *rbp, int cpt)
1348 {
1349         int              npages = rbp->rbp_npages;
1350         lnet_rtrbuf_t    *rb;
1351         struct list_head tmp;
1352
1353         if (rbp->rbp_nbuffers == 0) /* not initialized or already freed */
1354                 return;
1355
1356         INIT_LIST_HEAD(&tmp);
1357
1358         lnet_net_lock(cpt);
1359         lnet_drop_routed_msgs_locked(&rbp->rbp_msgs, cpt);
1360         list_splice_init(&rbp->rbp_bufs, &tmp);
1361         rbp->rbp_req_nbuffers = 0;
1362         rbp->rbp_nbuffers = rbp->rbp_credits = 0;
1363         rbp->rbp_mincredits = 0;
1364         lnet_net_unlock(cpt);
1365
1366         /* Free buffers on the free list. */
1367         while (!list_empty(&tmp)) {
1368                 rb = list_entry(tmp.next, lnet_rtrbuf_t, rb_list);
1369                 list_del(&rb->rb_list);
1370                 lnet_destroy_rtrbuf(rb, npages);
1371         }
1372 }
1373
1374 static int
1375 lnet_rtrpool_adjust_bufs(lnet_rtrbufpool_t *rbp, int nbufs, int cpt)
1376 {
1377         struct list_head rb_list;
1378         lnet_rtrbuf_t   *rb;
1379         int             num_rb;
1380         int             num_buffers = 0;
1381         int             old_req_nbufs;
1382         int             npages = rbp->rbp_npages;
1383
1384         lnet_net_lock(cpt);
1385         /* If we are called for less buffers than already in the pool, we
1386          * just lower the req_nbuffers number and excess buffers will be
1387          * thrown away as they are returned to the free list.  Credits
1388          * then get adjusted as well.
1389          * If we already have enough buffers allocated to serve the
1390          * increase requested, then we can treat that the same way as we
1391          * do the decrease. */
1392         num_rb = nbufs - rbp->rbp_nbuffers;
1393         if (nbufs <= rbp->rbp_req_nbuffers || num_rb <= 0) {
1394                 rbp->rbp_req_nbuffers = nbufs;
1395                 lnet_net_unlock(cpt);
1396                 return 0;
1397         }
1398         /* store the older value of rbp_req_nbuffers and then set it to
1399          * the new request to prevent lnet_return_rx_credits_locked() from
1400          * freeing buffers that we need to keep around */
1401         old_req_nbufs = rbp->rbp_req_nbuffers;
1402         rbp->rbp_req_nbuffers = nbufs;
1403         lnet_net_unlock(cpt);
1404
1405         INIT_LIST_HEAD(&rb_list);
1406
1407         /* allocate the buffers on a local list first.  If all buffers are
1408          * allocated successfully then join this list to the rbp buffer
1409          * list.  If not then free all allocated buffers. */
1410         while (num_rb-- > 0) {
1411                 rb = lnet_new_rtrbuf(rbp, cpt);
1412                 if (rb == NULL) {
1413                         CERROR("Failed to allocate %d route bufs of %d pages\n",
1414                                nbufs, npages);
1415
1416                         lnet_net_lock(cpt);
1417                         rbp->rbp_req_nbuffers = old_req_nbufs;
1418                         lnet_net_unlock(cpt);
1419
1420                         goto failed;
1421                 }
1422
1423                 list_add(&rb->rb_list, &rb_list);
1424                 num_buffers++;
1425         }
1426
1427         lnet_net_lock(cpt);
1428
1429         list_splice_tail(&rb_list, &rbp->rbp_bufs);
1430         rbp->rbp_nbuffers += num_buffers;
1431         rbp->rbp_credits += num_buffers;
1432         rbp->rbp_mincredits = rbp->rbp_credits;
1433         /* We need to schedule blocked msg using the newly
1434          * added buffers. */
1435         while (!list_empty(&rbp->rbp_bufs) &&
1436                !list_empty(&rbp->rbp_msgs))
1437                 lnet_schedule_blocked_locked(rbp);
1438
1439         lnet_net_unlock(cpt);
1440
1441         return 0;
1442
1443 failed:
1444         while (!list_empty(&rb_list)) {
1445                 rb = list_entry(rb_list.next, lnet_rtrbuf_t, rb_list);
1446                 list_del(&rb->rb_list);
1447                 lnet_destroy_rtrbuf(rb, npages);
1448         }
1449
1450         return -ENOMEM;
1451 }
1452
1453 static void
1454 lnet_rtrpool_init(lnet_rtrbufpool_t *rbp, int npages)
1455 {
1456         INIT_LIST_HEAD(&rbp->rbp_msgs);
1457         INIT_LIST_HEAD(&rbp->rbp_bufs);
1458
1459         rbp->rbp_npages = npages;
1460         rbp->rbp_credits = 0;
1461         rbp->rbp_mincredits = 0;
1462 }
1463
1464 void
1465 lnet_rtrpools_free(int keep_pools)
1466 {
1467         lnet_rtrbufpool_t *rtrp;
1468         int               i;
1469
1470         if (the_lnet.ln_rtrpools == NULL) /* uninitialized or freed */
1471                 return;
1472
1473         cfs_percpt_for_each(rtrp, i, the_lnet.ln_rtrpools) {
1474                 lnet_rtrpool_free_bufs(&rtrp[LNET_TINY_BUF_IDX], i);
1475                 lnet_rtrpool_free_bufs(&rtrp[LNET_SMALL_BUF_IDX], i);
1476                 lnet_rtrpool_free_bufs(&rtrp[LNET_LARGE_BUF_IDX], i);
1477         }
1478
1479         if (!keep_pools) {
1480                 cfs_percpt_free(the_lnet.ln_rtrpools);
1481                 the_lnet.ln_rtrpools = NULL;
1482         }
1483 }
1484
1485 static int
1486 lnet_nrb_tiny_calculate(void)
1487 {
1488         int     nrbs = LNET_NRB_TINY;
1489
1490         if (tiny_router_buffers < 0) {
1491                 LCONSOLE_ERROR_MSG(0x10c,
1492                                    "tiny_router_buffers=%d invalid when "
1493                                    "routing enabled\n", tiny_router_buffers);
1494                 return -EINVAL;
1495         }
1496
1497         if (tiny_router_buffers > 0)
1498                 nrbs = tiny_router_buffers;
1499
1500         nrbs /= LNET_CPT_NUMBER;
1501         return max(nrbs, LNET_NRB_TINY_MIN);
1502 }
1503
1504 static int
1505 lnet_nrb_small_calculate(void)
1506 {
1507         int     nrbs = LNET_NRB_SMALL;
1508
1509         if (small_router_buffers < 0) {
1510                 LCONSOLE_ERROR_MSG(0x10c,
1511                                    "small_router_buffers=%d invalid when "
1512                                    "routing enabled\n", small_router_buffers);
1513                 return -EINVAL;
1514         }
1515
1516         if (small_router_buffers > 0)
1517                 nrbs = small_router_buffers;
1518
1519         nrbs /= LNET_CPT_NUMBER;
1520         return max(nrbs, LNET_NRB_SMALL_MIN);
1521 }
1522
1523 static int
1524 lnet_nrb_large_calculate(void)
1525 {
1526         int     nrbs = LNET_NRB_LARGE;
1527
1528         if (large_router_buffers < 0) {
1529                 LCONSOLE_ERROR_MSG(0x10c,
1530                                    "large_router_buffers=%d invalid when "
1531                                    "routing enabled\n", large_router_buffers);
1532                 return -EINVAL;
1533         }
1534
1535         if (large_router_buffers > 0)
1536                 nrbs = large_router_buffers;
1537
1538         nrbs /= LNET_CPT_NUMBER;
1539         return max(nrbs, LNET_NRB_LARGE_MIN);
1540 }
1541
1542 int
1543 lnet_rtrpools_alloc(int im_a_router)
1544 {
1545         lnet_rtrbufpool_t *rtrp;
1546         int     nrb_tiny;
1547         int     nrb_small;
1548         int     nrb_large;
1549         int     rc;
1550         int     i;
1551
1552         if (!strcmp(forwarding, "")) {
1553                 /* not set either way */
1554                 if (!im_a_router)
1555                         return 0;
1556         } else if (!strcmp(forwarding, "disabled")) {
1557                 /* explicitly disabled */
1558                 return 0;
1559         } else if (!strcmp(forwarding, "enabled")) {
1560                 /* explicitly enabled */
1561         } else {
1562                 LCONSOLE_ERROR_MSG(0x10b, "'forwarding' not set to either "
1563                                    "'enabled' or 'disabled'\n");
1564                 return -EINVAL;
1565         }
1566
1567         nrb_tiny = lnet_nrb_tiny_calculate();
1568         if (nrb_tiny < 0)
1569                 return -EINVAL;
1570
1571         nrb_small = lnet_nrb_small_calculate();
1572         if (nrb_small < 0)
1573                 return -EINVAL;
1574
1575         nrb_large = lnet_nrb_large_calculate();
1576         if (nrb_large < 0)
1577                 return -EINVAL;
1578
1579         the_lnet.ln_rtrpools = cfs_percpt_alloc(lnet_cpt_table(),
1580                                                 LNET_NRBPOOLS *
1581                                                 sizeof(lnet_rtrbufpool_t));
1582         if (the_lnet.ln_rtrpools == NULL) {
1583                 LCONSOLE_ERROR_MSG(0x10c,
1584                                    "Failed to initialize router buffe pool\n");
1585                 return -ENOMEM;
1586         }
1587
1588         cfs_percpt_for_each(rtrp, i, the_lnet.ln_rtrpools) {
1589                 lnet_rtrpool_init(&rtrp[LNET_TINY_BUF_IDX], 0);
1590                 rc = lnet_rtrpool_adjust_bufs(&rtrp[LNET_TINY_BUF_IDX],
1591                                               nrb_tiny, i);
1592                 if (rc != 0)
1593                         goto failed;
1594
1595                 lnet_rtrpool_init(&rtrp[LNET_SMALL_BUF_IDX],
1596                                   LNET_NRB_SMALL_PAGES);
1597                 rc = lnet_rtrpool_adjust_bufs(&rtrp[LNET_SMALL_BUF_IDX],
1598                                               nrb_small, i);
1599                 if (rc != 0)
1600                         goto failed;
1601
1602                 lnet_rtrpool_init(&rtrp[LNET_LARGE_BUF_IDX],
1603                                   LNET_NRB_LARGE_PAGES);
1604                 rc = lnet_rtrpool_adjust_bufs(&rtrp[LNET_LARGE_BUF_IDX],
1605                                               nrb_large, i);
1606                 if (rc != 0)
1607                         goto failed;
1608         }
1609
1610         lnet_net_lock(LNET_LOCK_EX);
1611         the_lnet.ln_routing = 1;
1612         lnet_net_unlock(LNET_LOCK_EX);
1613         return 0;
1614
1615  failed:
1616         lnet_rtrpools_free(0);
1617         return rc;
1618 }
1619
1620 static int
1621 lnet_rtrpools_adjust_helper(int tiny, int small, int large)
1622 {
1623         int nrb = 0;
1624         int rc = 0;
1625         int i;
1626         lnet_rtrbufpool_t *rtrp;
1627
1628         /* If the provided values for each buffer pool are different than the
1629          * configured values, we need to take action. */
1630         if (tiny >= 0) {
1631                 tiny_router_buffers = tiny;
1632                 nrb = lnet_nrb_tiny_calculate();
1633                 cfs_percpt_for_each(rtrp, i, the_lnet.ln_rtrpools) {
1634                         rc = lnet_rtrpool_adjust_bufs(&rtrp[LNET_TINY_BUF_IDX],
1635                                                       nrb, i);
1636                         if (rc != 0)
1637                                 return rc;
1638                 }
1639         }
1640         if (small >= 0) {
1641                 small_router_buffers = small;
1642                 nrb = lnet_nrb_small_calculate();
1643                 cfs_percpt_for_each(rtrp, i, the_lnet.ln_rtrpools) {
1644                         rc = lnet_rtrpool_adjust_bufs(&rtrp[LNET_SMALL_BUF_IDX],
1645                                                       nrb, i);
1646                         if (rc != 0)
1647                                 return rc;
1648                 }
1649         }
1650         if (large >= 0) {
1651                 large_router_buffers = large;
1652                 nrb = lnet_nrb_large_calculate();
1653                 cfs_percpt_for_each(rtrp, i, the_lnet.ln_rtrpools) {
1654                         rc = lnet_rtrpool_adjust_bufs(&rtrp[LNET_LARGE_BUF_IDX],
1655                                                       nrb, i);
1656                         if (rc != 0)
1657                                 return rc;
1658                 }
1659         }
1660
1661         return 0;
1662 }
1663
1664 int
1665 lnet_rtrpools_adjust(int tiny, int small, int large)
1666 {
1667         /* this function doesn't revert the changes if adding new buffers
1668          * failed.  It's up to the user space caller to revert the
1669          * changes. */
1670
1671         if (!the_lnet.ln_routing)
1672                 return 0;
1673
1674         return lnet_rtrpools_adjust_helper(tiny, small, large);
1675 }
1676
1677 int
1678 lnet_rtrpools_enable(void)
1679 {
1680         int rc = 0;
1681
1682         if (the_lnet.ln_routing)
1683                 return 0;
1684
1685         if (the_lnet.ln_rtrpools == NULL)
1686                 /* If routing is turned off, and we have never
1687                  * initialized the pools before, just call the
1688                  * standard buffer pool allocation routine as
1689                  * if we are just configuring this for the first
1690                  * time. */
1691                 rc = lnet_rtrpools_alloc(1);
1692         else
1693                 rc = lnet_rtrpools_adjust_helper(0, 0, 0);
1694         if (rc != 0)
1695                 return rc;
1696
1697         lnet_net_lock(LNET_LOCK_EX);
1698         the_lnet.ln_routing = 1;
1699
1700         the_lnet.ln_ping_info->pi_features &= ~LNET_PING_FEAT_RTE_DISABLED;
1701         lnet_net_unlock(LNET_LOCK_EX);
1702
1703         return rc;
1704 }
1705
1706 void
1707 lnet_rtrpools_disable(void)
1708 {
1709         if (!the_lnet.ln_routing)
1710                 return;
1711
1712         lnet_net_lock(LNET_LOCK_EX);
1713         the_lnet.ln_routing = 0;
1714         the_lnet.ln_ping_info->pi_features |= LNET_PING_FEAT_RTE_DISABLED;
1715
1716         tiny_router_buffers = 0;
1717         small_router_buffers = 0;
1718         large_router_buffers = 0;
1719         lnet_net_unlock(LNET_LOCK_EX);
1720         lnet_rtrpools_free(1);
1721 }
1722
1723 int
1724 lnet_notify(lnet_ni_t *ni, lnet_nid_t nid, int alive, cfs_time_t when)
1725 {
1726         struct lnet_peer_ni     *lp = NULL;
1727         cfs_time_t              now = cfs_time_current();
1728         int                     cpt = lnet_cpt_of_nid(nid, ni);
1729
1730         LASSERT (!in_interrupt ());
1731
1732         CDEBUG (D_NET, "%s notifying %s: %s\n",
1733                 (ni == NULL) ? "userspace" : libcfs_nid2str(ni->ni_nid),
1734                 libcfs_nid2str(nid),
1735                 alive ? "up" : "down");
1736
1737         if (ni != NULL &&
1738             LNET_NIDNET(ni->ni_nid) != LNET_NIDNET(nid)) {
1739                 CWARN("Ignoring notification of %s %s by %s (different net)\n",
1740                       libcfs_nid2str(nid), alive ? "birth" : "death",
1741                       libcfs_nid2str(ni->ni_nid));
1742                 return -EINVAL;
1743         }
1744
1745         /* can't do predictions... */
1746         if (cfs_time_after(when, now)) {
1747                 CWARN("Ignoring prediction from %s of %s %s "
1748                       "%ld seconds in the future\n",
1749                       (ni == NULL) ? "userspace" : libcfs_nid2str(ni->ni_nid),
1750                       libcfs_nid2str(nid), alive ? "up" : "down",
1751                       cfs_duration_sec(cfs_time_sub(when, now)));
1752                 return -EINVAL;
1753         }
1754
1755         if (ni != NULL && !alive &&             /* LND telling me she's down */
1756             !auto_down) {                       /* auto-down disabled */
1757                 CDEBUG(D_NET, "Auto-down disabled\n");
1758                 return 0;
1759         }
1760
1761         lnet_net_lock(cpt);
1762
1763         if (the_lnet.ln_shutdown) {
1764                 lnet_net_unlock(cpt);
1765                 return -ESHUTDOWN;
1766         }
1767
1768         lp = lnet_find_peer_ni_locked(nid);
1769         if (lp == NULL) {
1770                 /* nid not found */
1771                 lnet_net_unlock(cpt);
1772                 CDEBUG(D_NET, "%s not found\n", libcfs_nid2str(nid));
1773                 return 0;
1774         }
1775
1776         /* We can't fully trust LND on reporting exact peer last_alive
1777          * if he notifies us about dead peer. For example ksocklnd can
1778          * call us with when == _time_when_the_node_was_booted_ if
1779          * no connections were successfully established */
1780         if (ni != NULL && !alive && when < lp->lpni_last_alive)
1781                 when = lp->lpni_last_alive;
1782
1783         lnet_notify_locked(lp, ni == NULL, alive, when);
1784
1785         if (ni != NULL)
1786                 lnet_ni_notify_locked(ni, lp);
1787
1788         lnet_peer_ni_decref_locked(lp);
1789
1790         lnet_net_unlock(cpt);
1791         return 0;
1792 }
1793 EXPORT_SYMBOL(lnet_notify);