lnet/lnet/router.c

   1 /*
   2  * Copyright (c) 2007, 2010, Oracle and/or its affiliates. All rights reserved.
   3  *
   4  * Copyright (c) 2011, 2017, Intel Corporation.
   5  *
   6  *   This file is part of Lustre, https://wiki.whamcloud.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
  25 #include <linux/random.h>
  26 #include <lnet/lib-lnet.h>
  27
  28 #define LNET_NRB_TINY_MIN       512     /* min value for each CPT */
  29 #define LNET_NRB_TINY           (LNET_NRB_TINY_MIN * 4)
  30 #define LNET_NRB_SMALL_MIN      4096    /* min value for each CPT */
  31 #define LNET_NRB_SMALL          (LNET_NRB_SMALL_MIN * 4)
  32 #define LNET_NRB_SMALL_PAGES    1
  33 #define LNET_NRB_LARGE_MIN      256     /* min value for each CPT */
  34 #define LNET_NRB_LARGE          (LNET_NRB_LARGE_MIN * 4)
  35 #define LNET_NRB_LARGE_PAGES    ((LNET_MTU + PAGE_SIZE - 1) >> \
  36                                   PAGE_SHIFT)
  37
  38 static char *forwarding = "";
  39 module_param(forwarding, charp, 0444);
  40 MODULE_PARM_DESC(forwarding, "Explicitly enable/disable forwarding between networks");
  41
  42 static int tiny_router_buffers;
  43 module_param(tiny_router_buffers, int, 0444);
  44 MODULE_PARM_DESC(tiny_router_buffers, "# of 0 payload messages to buffer in the router");
  45 static int small_router_buffers;
  46 module_param(small_router_buffers, int, 0444);
  47 MODULE_PARM_DESC(small_router_buffers, "# of small (1 page) messages to buffer in the router");
  48 static int large_router_buffers;
  49 module_param(large_router_buffers, int, 0444);
  50 MODULE_PARM_DESC(large_router_buffers, "# of large messages to buffer in the router");
  51 static int peer_buffer_credits;
  52 module_param(peer_buffer_credits, int, 0444);
  53 MODULE_PARM_DESC(peer_buffer_credits, "# router buffer credits per peer");
  54
  55 static int auto_down = 1;
  56 module_param(auto_down, int, 0444);
  57 MODULE_PARM_DESC(auto_down, "Automatically mark peers down on comms error");
  58
  59 int
  60 lnet_peer_buffer_credits(struct lnet_net *net)
  61 {
  62         /* NI option overrides LNet default */
  63         if (net->net_tunables.lct_peer_rtr_credits > 0)
  64                 return net->net_tunables.lct_peer_rtr_credits;
  65         if (peer_buffer_credits > 0)
  66                 return peer_buffer_credits;
  67
  68         /* As an approximation, allow this peer the same number of router
  69          * buffers as it is allowed outstanding sends */
  70         return net->net_tunables.lct_peer_tx_credits;
  71 }
  72
  73 static int check_routers_before_use;
  74 module_param(check_routers_before_use, int, 0444);
  75 MODULE_PARM_DESC(check_routers_before_use, "Assume routers are down and ping them before use");
  76
  77 int avoid_asym_router_failure = 1;
  78 module_param(avoid_asym_router_failure, int, 0644);
  79 MODULE_PARM_DESC(avoid_asym_router_failure, "Avoid asymmetrical router failures (0 to disable)");
  80
  81 int alive_router_check_interval = 60;
  82 module_param(alive_router_check_interval, int, 0644);
  83 MODULE_PARM_DESC(alive_router_check_interval, "Seconds between live router health checks (<= 0 to disable)");
  84
  85 static int router_ping_timeout = 50;
  86 module_param(router_ping_timeout, int, 0644);
  87 MODULE_PARM_DESC(router_ping_timeout, "Seconds to wait for the reply to a router health query");
  88
  89 /*
  90  * A value between 0 and 100. 0 meaning that even if router's interfaces
  91  * have the worse health still consider the gateway usable.
  92  * 100 means that at least one interface on the route's remote net is 100%
  93  * healthy to consider the route alive.
  94  * The default is set to 100 to ensure we maintain the original behavior.
  95  */
  96 unsigned int router_sensitivity_percentage = 100;
  97 static int rtr_sensitivity_set(const char *val, cfs_kernel_param_arg_t *kp);
  98 static struct kernel_param_ops param_ops_rtr_sensitivity = {
  99         .set = rtr_sensitivity_set,
 100         .get = param_get_int,
 101 };
 102 #define param_check_rtr_sensitivity(name, p) \
 103                 __param_check(name, p, int)
 104 #ifdef HAVE_KERNEL_PARAM_OPS
 105 module_param(router_sensitivity_percentage, rtr_sensitivity, S_IRUGO|S_IWUSR);
 106 #else
 107 module_param_call(router_sensitivity_percentage, rtr_sensitivity_set, param_get_int,
 108                   &router_sensitivity_percentage, S_IRUGO|S_IWUSR);
 109 #endif
 110 MODULE_PARM_DESC(router_sensitivity_percentage,
 111                 "How healthy a gateway should be to be used in percent");
 112
 113 static int
 114 rtr_sensitivity_set(const char *val, cfs_kernel_param_arg_t *kp)
 115 {
 116         int rc;
 117         unsigned *sen = (unsigned *)kp->arg;
 118         unsigned long value;
 119
 120         rc = kstrtoul(val, 0, &value);
 121         if (rc) {
 122                 CERROR("Invalid module parameter value for 'router_sensitivity_percentage'\n");
 123                 return rc;
 124         }
 125
 126         if (value < 0 || value > 100) {
 127                 CERROR("Invalid value: %lu for 'router_sensitivity_percentage'\n", value);
 128                 return -EINVAL;
 129         }
 130
 131         /*
 132          * The purpose of locking the api_mutex here is to ensure that
 133          * the correct value ends up stored properly.
 134          */
 135         mutex_lock(&the_lnet.ln_api_mutex);
 136
 137         *sen = value;
 138
 139         mutex_unlock(&the_lnet.ln_api_mutex);
 140
 141         return 0;
 142 }
 143
 144 int
 145 lnet_peers_start_down(void)
 146 {
 147         return check_routers_before_use;
 148 }
 149
 150 /*
 151  * A net is alive if at least one gateway NI on the network is alive.
 152  */
 153 static bool
 154 lnet_is_gateway_net_alive(struct lnet_peer_net *lpn)
 155 {
 156         struct lnet_peer_ni *lpni;
 157
 158         list_for_each_entry(lpni, &lpn->lpn_peer_nis, lpni_peer_nis) {
 159                 if (lnet_is_peer_ni_alive(lpni))
 160                         return true;
 161         }
 162
 163         return false;
 164 }
 165
 166 /*
 167  * a gateway is alive only if all its nets are alive
 168  * called with cpt lock held
 169  */
 170 bool lnet_is_gateway_alive(struct lnet_peer *gw)
 171 {
 172         struct lnet_peer_net *lpn;
 173
 174         list_for_each_entry(lpn, &gw->lp_peer_nets, lpn_peer_nets) {
 175                 if (!lnet_is_gateway_net_alive(lpn))
 176                         return false;
 177         }
 178
 179         return true;
 180 }
 181
 182 /*
 183  * lnet_is_route_alive() needs to be called with cpt lock held
 184  * A route is alive if the gateway can route between the local network and
 185  * the remote network of the route.
 186  * This means at least one NI is alive on each of the local and remote
 187  * networks of the gateway.
 188  */
 189 bool lnet_is_route_alive(struct lnet_route *route)
 190 {
 191         struct lnet_peer *gw = route->lr_gateway;
 192         struct lnet_peer_net *llpn;
 193         struct lnet_peer_net *rlpn;
 194         bool route_alive;
 195
 196         /*
 197          * check the gateway's interfaces on the route rnet to make sure
 198          * that the gateway is viable.
 199          */
 200         llpn = lnet_peer_get_net_locked(gw, route->lr_lnet);
 201         if (!llpn)
 202                 return false;
 203
 204         route_alive = lnet_is_gateway_net_alive(llpn);
 205
 206         if (avoid_asym_router_failure) {
 207                 rlpn = lnet_peer_get_net_locked(gw, route->lr_net);
 208                 if (!rlpn)
 209                         return false;
 210                 route_alive = route_alive &&
 211                               lnet_is_gateway_net_alive(rlpn);
 212         }
 213
 214         if (!route_alive)
 215                 return route_alive;
 216
 217         spin_lock(&gw->lp_lock);
 218         if (!(gw->lp_state & LNET_PEER_ROUTER_ENABLED)) {
 219                 if (gw->lp_rtr_refcount > 0)
 220                         CERROR("peer %s is being used as a gateway but routing feature is not turned on\n",
 221                                libcfs_nid2str(gw->lp_primary_nid));
 222                 route_alive = false;
 223         }
 224         spin_unlock(&gw->lp_lock);
 225
 226         return route_alive;
 227 }
 228
 229 void
 230 lnet_consolidate_routes_locked(struct lnet_peer *orig_lp,
 231                                struct lnet_peer *new_lp)
 232 {
 233         struct lnet_peer_ni *lpni;
 234         struct lnet_route *route;
 235
 236         /*
 237          * Although a route is correlated with a peer, but when it's added
 238          * a specific NID is used. That NID refers to a peer_ni within
 239          * a peer. There could be other peer_nis on the same net, which
 240          * can be used to send to that gateway. However when we are
 241          * consolidating gateways because of discovery, the nid used to
 242          * add the route might've moved between gateway peers. In this
 243          * case we want to move the route to the new gateway as well. The
 244          * intent here is not to confuse the user who added the route.
 245          */
 246         list_for_each_entry(route, &orig_lp->lp_routes, lr_gwlist) {
 247                 lpni = lnet_peer_get_ni_locked(orig_lp, route->lr_nid);
 248                 if (!lpni) {
 249                         lnet_net_lock(LNET_LOCK_EX);
 250                         list_move(&route->lr_gwlist, &new_lp->lp_routes);
 251                         lnet_net_unlock(LNET_LOCK_EX);
 252                 }
 253         }
 254
 255 }
 256
 257 void
 258 lnet_router_discovery_complete(struct lnet_peer *lp)
 259 {
 260         struct lnet_peer_ni *lpni = NULL;
 261
 262         spin_lock(&lp->lp_lock);
 263         lp->lp_state &= ~LNET_PEER_RTR_DISCOVERY;
 264         spin_unlock(&lp->lp_lock);
 265
 266         /*
 267          * Router discovery successful? All peer information would've been
 268          * updated already. No need to do any more processing
 269          */
 270         if (!lp->lp_dc_error)
 271                 return;
 272         /*
 273          * discovery failed? then we need to set the status of each lpni
 274          * to DOWN. It will be updated the next time we discover the
 275          * router. For router peer NIs not on local networks, we never send
 276          * messages directly to them, so their health will always remain
 277          * at maximum. We can only tell if they are up or down from the
 278          * status returned in the PING response. If we fail to get that
 279          * status in our scheduled router discovery, then we'll assume
 280          * it's down until we're told otherwise.
 281          */
 282         CDEBUG(D_NET, "%s: Router discovery failed %d\n",
 283                libcfs_nid2str(lp->lp_primary_nid), lp->lp_dc_error);
 284         while ((lpni = lnet_get_next_peer_ni_locked(lp, NULL, lpni)) != NULL)
 285                 lpni->lpni_ns_status = LNET_NI_STATUS_DOWN;
 286 }
 287
 288 static void
 289 lnet_rtr_addref_locked(struct lnet_peer *lp)
 290 {
 291         LASSERT(lp->lp_rtr_refcount >= 0);
 292
 293         /* lnet_net_lock must be exclusively locked */
 294         lp->lp_rtr_refcount++;
 295         if (lp->lp_rtr_refcount == 1) {
 296                 list_add_tail(&lp->lp_rtr_list, &the_lnet.ln_routers);
 297                 /* addref for the_lnet.ln_routers */
 298                 lnet_peer_addref_locked(lp);
 299                 the_lnet.ln_routers_version++;
 300         }
 301 }
 302
 303 static void
 304 lnet_rtr_decref_locked(struct lnet_peer *lp)
 305 {
 306         LASSERT(atomic_read(&lp->lp_refcount) > 0);
 307         LASSERT(lp->lp_rtr_refcount > 0);
 308
 309         /* lnet_net_lock must be exclusively locked */
 310         lp->lp_rtr_refcount--;
 311         if (lp->lp_rtr_refcount == 0) {
 312                 LASSERT(list_empty(&lp->lp_routes));
 313
 314                 list_del(&lp->lp_rtr_list);
 315                 /* decref for the_lnet.ln_routers */
 316                 lnet_peer_decref_locked(lp);
 317                 the_lnet.ln_routers_version++;
 318         }
 319 }
 320
 321 struct lnet_remotenet *
 322 lnet_find_rnet_locked(__u32 net)
 323 {
 324         struct lnet_remotenet *rnet;
 325         struct list_head *tmp;
 326         struct list_head *rn_list;
 327
 328         LASSERT(the_lnet.ln_state == LNET_STATE_RUNNING);
 329
 330         rn_list = lnet_net2rnethash(net);
 331         list_for_each(tmp, rn_list) {
 332                 rnet = list_entry(tmp, struct lnet_remotenet, lrn_list);
 333
 334                 if (rnet->lrn_net == net)
 335                         return rnet;
 336         }
 337         return NULL;
 338 }
 339
 340 static void lnet_shuffle_seed(void)
 341 {
 342         static int seeded;
 343         struct lnet_ni *ni = NULL;
 344
 345         if (seeded)
 346                 return;
 347
 348         /* Nodes with small feet have little entropy
 349          * the NID for this node gives the most entropy in the low bits */
 350         while ((ni = lnet_get_next_ni_locked(NULL, ni)))
 351                 add_device_randomness(&ni->ni_nid, sizeof(ni->ni_nid));
 352
 353         seeded = 1;
 354         return;
 355 }
 356
 357 /* NB expects LNET_LOCK held */
 358 static void
 359 lnet_add_route_to_rnet(struct lnet_remotenet *rnet, struct lnet_route *route)
 360 {
 361         unsigned int len = 0;
 362         unsigned int offset = 0;
 363         struct list_head *e;
 364
 365         lnet_shuffle_seed();
 366
 367         list_for_each(e, &rnet->lrn_routes)
 368                 len++;
 369
 370         /*
 371          * Randomly adding routes to the list is done to ensure that when
 372          * different nodes are using the same list of routers, they end up
 373          * preferring different routers.
 374          */
 375         offset = cfs_rand() % (len + 1);
 376         list_for_each(e, &rnet->lrn_routes) {
 377                 if (offset == 0)
 378                         break;
 379                 offset--;
 380         }
 381         list_add(&route->lr_list, e);
 382         /*
 383          * force a router check on the gateway to make sure the route is
 384          * alive
 385          */
 386         route->lr_gateway->lp_rtrcheck_timestamp = 0;
 387
 388         the_lnet.ln_remote_nets_version++;
 389
 390         /* add the route on the gateway list */
 391         list_add(&route->lr_gwlist, &route->lr_gateway->lp_routes);
 392
 393         /* take a router reference count on the gateway */
 394         lnet_rtr_addref_locked(route->lr_gateway);
 395 }
 396
 397 int
 398 lnet_add_route(__u32 net, __u32 hops, lnet_nid_t gateway,
 399                unsigned int priority)
 400 {
 401         struct list_head *route_entry;
 402         struct lnet_remotenet *rnet;
 403         struct lnet_remotenet *rnet2;
 404         struct lnet_route *route;
 405         struct lnet_peer_ni *lpni;
 406         struct lnet_peer *gw;
 407         int add_route;
 408         int rc;
 409
 410         CDEBUG(D_NET, "Add route: remote net %s hops %d priority %u gw %s\n",
 411                libcfs_net2str(net), hops, priority, libcfs_nid2str(gateway));
 412
 413         if (gateway == LNET_NID_ANY ||
 414             LNET_NETTYP(LNET_NIDNET(gateway)) == LOLND ||
 415             net == LNET_NIDNET(LNET_NID_ANY) ||
 416             LNET_NETTYP(net) == LOLND ||
 417             LNET_NIDNET(gateway) == net ||
 418             (hops != LNET_UNDEFINED_HOPS && (hops < 1 || hops > 255)))
 419                 return -EINVAL;
 420
 421         /* it's a local network */
 422         if (lnet_islocalnet(net))
 423                 return -EEXIST;
 424
 425         /* Assume net, route, all new */
 426         LIBCFS_ALLOC(route, sizeof(*route));
 427         LIBCFS_ALLOC(rnet, sizeof(*rnet));
 428         if (route == NULL || rnet == NULL) {
 429                 CERROR("Out of memory creating route %s %d %s\n",
 430                        libcfs_net2str(net), hops, libcfs_nid2str(gateway));
 431                 if (route != NULL)
 432                         LIBCFS_FREE(route, sizeof(*route));
 433                 if (rnet != NULL)
 434                         LIBCFS_FREE(rnet, sizeof(*rnet));
 435                 return -ENOMEM;
 436         }
 437
 438         INIT_LIST_HEAD(&rnet->lrn_routes);
 439         rnet->lrn_net = net;
 440         /* store the local and remote net that the route represents */
 441         route->lr_lnet = LNET_NIDNET(gateway);
 442         route->lr_net = net;
 443         route->lr_nid = gateway;
 444         route->lr_priority = priority;
 445         route->lr_hops = hops;
 446
 447         lnet_net_lock(LNET_LOCK_EX);
 448
 449         /*
 450          * lnet_nid2peerni_ex() grabs a ref on the lpni. We will need to
 451          * lose that once we're done
 452          */
 453         lpni = lnet_nid2peerni_ex(gateway, LNET_LOCK_EX);
 454         if (IS_ERR(lpni)) {
 455                 lnet_net_unlock(LNET_LOCK_EX);
 456
 457                 LIBCFS_FREE(route, sizeof(*route));
 458                 LIBCFS_FREE(rnet, sizeof(*rnet));
 459
 460                 rc = PTR_ERR(lpni);
 461                 CERROR("Error %d creating route %s %d %s\n", rc,
 462                         libcfs_net2str(net), hops,
 463                         libcfs_nid2str(gateway));
 464                 return rc;
 465         }
 466
 467         LASSERT(lpni->lpni_peer_net && lpni->lpni_peer_net->lpn_peer);
 468         gw = lpni->lpni_peer_net->lpn_peer;
 469
 470         route->lr_gateway = gw;
 471
 472         rnet2 = lnet_find_rnet_locked(net);
 473         if (rnet2 == NULL) {
 474                 /* new network */
 475                 list_add_tail(&rnet->lrn_list, lnet_net2rnethash(net));
 476                 rnet2 = rnet;
 477         }
 478
 479         /* Search for a duplicate route (it's a NOOP if it is) */
 480         add_route = 1;
 481         list_for_each(route_entry, &rnet2->lrn_routes) {
 482                 struct lnet_route *route2;
 483
 484                 route2 = list_entry(route_entry, struct lnet_route, lr_list);
 485                 if (route2->lr_gateway == route->lr_gateway) {
 486                         add_route = 0;
 487                         break;
 488                 }
 489
 490                 /* our lookups must be true */
 491                 LASSERT(route2->lr_gateway->lp_primary_nid != gateway);
 492         }
 493
 494         /*
 495          * It is possible to add multiple routes through the same peer,
 496          * but it'll be using a different NID of that peer. When the
 497          * gateway is discovered, discovery will consolidate the different
 498          * peers into one peer. In this case the discovery code will have
 499          * to move the routes from the peer that's being deleted to the
 500          * consolidated peer lp_routes list
 501          */
 502         if (add_route)
 503                 lnet_add_route_to_rnet(rnet2, route);
 504
 505         /*
 506          * get rid of the reference on the lpni.
 507          */
 508         lnet_peer_ni_decref_locked(lpni);
 509         lnet_net_unlock(LNET_LOCK_EX);
 510
 511         rc = 0;
 512
 513         if (!add_route) {
 514                 rc = -EEXIST;
 515                 LIBCFS_FREE(route, sizeof(*route));
 516         }
 517
 518         if (rnet != rnet2)
 519                 LIBCFS_FREE(rnet, sizeof(*rnet));
 520
 521         /* kick start the monitor thread to handle the added route */
 522         wake_up(&the_lnet.ln_mt_waitq);
 523
 524         return rc;
 525 }
 526
 527 static void
 528 lnet_del_route_from_rnet(lnet_nid_t gw_nid, struct list_head *route_list,
 529                          struct list_head *zombies)
 530 {
 531         struct lnet_peer *gateway;
 532         struct lnet_route *route;
 533         struct lnet_route *tmp;
 534
 535         list_for_each_entry_safe(route, tmp, route_list, lr_list) {
 536                 gateway = route->lr_gateway;
 537                 if (gw_nid != LNET_NID_ANY &&
 538                     gw_nid != gateway->lp_primary_nid)
 539                         continue;
 540
 541                 /*
 542                  * move to zombie to delete outside the lock
 543                  * Note that this function is called with the
 544                  * ln_api_mutex held as well as the exclusive net
 545                  * lock. Adding to the remote net list happens
 546                  * under the same conditions. Same goes for the
 547                  * gateway router list
 548                  */
 549                 list_move(&route->lr_list, zombies);
 550                 the_lnet.ln_remote_nets_version++;
 551
 552                 list_del(&route->lr_gwlist);
 553                 lnet_rtr_decref_locked(gateway);
 554         }
 555 }
 556
 557 int
 558 lnet_del_route(__u32 net, lnet_nid_t gw_nid)
 559 {
 560         struct list_head rnet_zombies;
 561         struct lnet_remotenet *rnet;
 562         struct lnet_remotenet *tmp;
 563         struct list_head *rn_list;
 564         struct lnet_peer_ni *lpni;
 565         struct lnet_route *route;
 566         struct list_head zombies;
 567         struct lnet_peer *lp;
 568         int i = 0;
 569
 570         INIT_LIST_HEAD(&rnet_zombies);
 571         INIT_LIST_HEAD(&zombies);
 572
 573         CDEBUG(D_NET, "Del route: net %s : gw %s\n",
 574                libcfs_net2str(net), libcfs_nid2str(gw_nid));
 575
 576         /* NB Caller may specify either all routes via the given gateway
 577          * or a specific route entry actual NIDs) */
 578
 579         lnet_net_lock(LNET_LOCK_EX);
 580
 581         lpni = lnet_find_peer_ni_locked(gw_nid);
 582         if (lpni) {
 583                 lp = lpni->lpni_peer_net->lpn_peer;
 584                 LASSERT(lp);
 585                 gw_nid = lp->lp_primary_nid;
 586                 lnet_peer_ni_decref_locked(lpni);
 587         }
 588
 589         if (net != LNET_NIDNET(LNET_NID_ANY)) {
 590                 rnet = lnet_find_rnet_locked(net);
 591                 if (!rnet) {
 592                         lnet_net_unlock(LNET_LOCK_EX);
 593                         return -ENOENT;
 594                 }
 595                 lnet_del_route_from_rnet(gw_nid, &rnet->lrn_routes,
 596                                          &zombies);
 597                 if (list_empty(&rnet->lrn_routes))
 598                         list_move(&rnet->lrn_list, &rnet_zombies);
 599                 goto delete_zombies;
 600         }
 601
 602         for (i = 0; i < LNET_REMOTE_NETS_HASH_SIZE; i++) {
 603                 rn_list = &the_lnet.ln_remote_nets_hash[i];
 604
 605                 list_for_each_entry_safe(rnet, tmp, rn_list, lrn_list) {
 606                         lnet_del_route_from_rnet(gw_nid, &rnet->lrn_routes,
 607                                                  &zombies);
 608                         if (list_empty(&rnet->lrn_routes))
 609                                 list_move(&rnet->lrn_list, &rnet_zombies);
 610                 }
 611         }
 612
 613 delete_zombies:
 614         lnet_net_unlock(LNET_LOCK_EX);
 615
 616         while (!list_empty(&zombies)) {
 617                 route = list_first_entry(&zombies, struct lnet_route, lr_list);
 618                 list_del(&route->lr_list);
 619                 LIBCFS_FREE(route, sizeof(*route));
 620         }
 621
 622         while (!list_empty(&rnet_zombies)) {
 623                 rnet = list_first_entry(&rnet_zombies, struct lnet_remotenet,
 624                                         lrn_list);
 625                 list_del(&rnet->lrn_list);
 626                 LIBCFS_FREE(rnet, sizeof(*rnet));
 627         }
 628
 629         return 0;
 630 }
 631
 632 void
 633 lnet_destroy_routes (void)
 634 {
 635         lnet_del_route(LNET_NIDNET(LNET_NID_ANY), LNET_NID_ANY);
 636 }
 637
 638 int lnet_get_rtr_pool_cfg(int cpt, struct lnet_ioctl_pool_cfg *pool_cfg)
 639 {
 640         struct lnet_rtrbufpool *rbp;
 641         int i, rc = -ENOENT, j;
 642
 643         if (the_lnet.ln_rtrpools == NULL)
 644                 return rc;
 645
 646
 647         cfs_percpt_for_each(rbp, i, the_lnet.ln_rtrpools) {
 648                 if (i != cpt)
 649                         continue;
 650
 651                 lnet_net_lock(i);
 652                 for (j = 0; j < LNET_NRBPOOLS; j++) {
 653                         pool_cfg->pl_pools[j].pl_npages = rbp[j].rbp_npages;
 654                         pool_cfg->pl_pools[j].pl_nbuffers = rbp[j].rbp_nbuffers;
 655                         pool_cfg->pl_pools[j].pl_credits = rbp[j].rbp_credits;
 656                         pool_cfg->pl_pools[j].pl_mincredits = rbp[j].rbp_mincredits;
 657                 }
 658                 lnet_net_unlock(i);
 659                 rc = 0;
 660                 break;
 661         }
 662
 663         lnet_net_lock(LNET_LOCK_EX);
 664         pool_cfg->pl_routing = the_lnet.ln_routing;
 665         lnet_net_unlock(LNET_LOCK_EX);
 666
 667         return rc;
 668 }
 669
 670 int
 671 lnet_get_route(int idx, __u32 *net, __u32 *hops,
 672                lnet_nid_t *gateway, __u32 *alive, __u32 *priority)
 673 {
 674         struct list_head *e1;
 675         struct list_head *e2;
 676         struct lnet_remotenet *rnet;
 677         struct lnet_route        *route;
 678         int               cpt;
 679         int               i;
 680         struct list_head *rn_list;
 681
 682         cpt = lnet_net_lock_current();
 683
 684         for (i = 0; i < LNET_REMOTE_NETS_HASH_SIZE; i++) {
 685                 rn_list = &the_lnet.ln_remote_nets_hash[i];
 686                 list_for_each(e1, rn_list) {
 687                         rnet = list_entry(e1, struct lnet_remotenet, lrn_list);
 688
 689                         list_for_each(e2, &rnet->lrn_routes) {
 690                                 route = list_entry(e2, struct lnet_route,
 691                                                    lr_list);
 692
 693                                 if (idx-- == 0) {
 694                                         *net      = rnet->lrn_net;
 695                                         *gateway  = route->lr_nid;
 696                                         *hops     = route->lr_hops;
 697                                         *priority = route->lr_priority;
 698                                         *alive    = lnet_is_route_alive(route);
 699                                         lnet_net_unlock(cpt);
 700                                         return 0;
 701                                 }
 702                         }
 703                 }
 704         }
 705
 706         lnet_net_unlock(cpt);
 707         return -ENOENT;
 708 }
 709
 710 static void
 711 lnet_wait_known_routerstate(void)
 712 {
 713         struct lnet_peer *rtr;
 714         struct list_head *entry;
 715         int all_known;
 716
 717         LASSERT(the_lnet.ln_mt_state == LNET_MT_STATE_RUNNING);
 718
 719         for (;;) {
 720                 int cpt = lnet_net_lock_current();
 721
 722                 all_known = 1;
 723                 list_for_each(entry, &the_lnet.ln_routers) {
 724                         rtr = list_entry(entry, struct lnet_peer,
 725                                          lp_rtr_list);
 726
 727                         spin_lock(&rtr->lp_lock);
 728
 729                         if ((rtr->lp_state & LNET_PEER_DISCOVERED) == 0) {
 730                                 all_known = 0;
 731                                 spin_unlock(&rtr->lp_lock);
 732                                 break;
 733                         }
 734                         spin_unlock(&rtr->lp_lock);
 735                 }
 736
 737                 lnet_net_unlock(cpt);
 738
 739                 if (all_known)
 740                         return;
 741
 742                 set_current_state(TASK_UNINTERRUPTIBLE);
 743                 schedule_timeout(cfs_time_seconds(1));
 744         }
 745 }
 746
 747 static void
 748 lnet_update_ni_status_locked(void)
 749 {
 750         struct lnet_ni *ni = NULL;
 751         time64_t now;
 752         time64_t timeout;
 753
 754         LASSERT(the_lnet.ln_routing);
 755
 756         timeout = router_ping_timeout + alive_router_check_interval;
 757
 758         now = ktime_get_real_seconds();
 759         while ((ni = lnet_get_next_ni_locked(NULL, ni))) {
 760                 if (ni->ni_net->net_lnd->lnd_type == LOLND)
 761                         continue;
 762
 763                 if (now < ni->ni_last_alive + timeout)
 764                         continue;
 765
 766                 lnet_ni_lock(ni);
 767                 /* re-check with lock */
 768                 if (now < ni->ni_last_alive + timeout) {
 769                         lnet_ni_unlock(ni);
 770                         continue;
 771                 }
 772
 773                 LASSERT(ni->ni_status != NULL);
 774
 775                 if (ni->ni_status->ns_status != LNET_NI_STATUS_DOWN) {
 776                         CDEBUG(D_NET, "NI(%s:%lld) status changed to down\n",
 777                                libcfs_nid2str(ni->ni_nid), timeout);
 778                         /* NB: so far, this is the only place to set
 779                          * NI status to "down" */
 780                         ni->ni_status->ns_status = LNET_NI_STATUS_DOWN;
 781                 }
 782                 lnet_ni_unlock(ni);
 783         }
 784 }
 785
 786 void lnet_wait_router_start(void)
 787 {
 788         if (check_routers_before_use) {
 789                 /* Note that a helpful side-effect of pinging all known routers
 790                  * at startup is that it makes them drop stale connections they
 791                  * may have to a previous instance of me. */
 792                 lnet_wait_known_routerstate();
 793         }
 794 }
 795
 796 /*
 797  * This function is called from the monitor thread to check if there are
 798  * any active routers that need to be checked.
 799  */
 800 inline bool
 801 lnet_router_checker_active(void)
 802 {
 803         /* Router Checker thread needs to run when routing is enabled in
 804          * order to call lnet_update_ni_status_locked() */
 805         if (the_lnet.ln_routing)
 806                 return true;
 807
 808         return !list_empty(&the_lnet.ln_routers) &&
 809                 alive_router_check_interval > 0;
 810 }
 811
 812 void
 813 lnet_check_routers(void)
 814 {
 815         struct lnet_peer_ni *lpni;
 816         struct list_head *entry;
 817         struct lnet_peer *rtr;
 818         __u64 version;
 819         time64_t now;
 820         int cpt;
 821         int rc;
 822
 823         cpt = lnet_net_lock_current();
 824 rescan:
 825         version = the_lnet.ln_routers_version;
 826
 827         list_for_each(entry, &the_lnet.ln_routers) {
 828                 rtr = list_entry(entry, struct lnet_peer,
 829                                  lp_rtr_list);
 830
 831                 now = ktime_get_real_seconds();
 832
 833                 /*
 834                  * only discover the router if we've passed
 835                  * alive_router_check_interval seconds. Some of the router
 836                  * interfaces could be down and in that case they would be
 837                  * undergoing recovery separately from this discovery.
 838                  */
 839                 if (now - rtr->lp_rtrcheck_timestamp <
 840                     alive_router_check_interval)
 841                        continue;
 842
 843                 /*
 844                  * If we're currently discovering the peer then don't
 845                  * issue another discovery
 846                  */
 847                 spin_lock(&rtr->lp_lock);
 848                 if (rtr->lp_state & LNET_PEER_RTR_DISCOVERY) {
 849                         spin_unlock(&rtr->lp_lock);
 850                         continue;
 851                 }
 852                 /* make sure we actively discover the router */
 853                 rtr->lp_state &= ~LNET_PEER_NIDS_UPTODATE;
 854                 rtr->lp_state |= LNET_PEER_RTR_DISCOVERY;
 855                 spin_unlock(&rtr->lp_lock);
 856
 857                 /* find the peer_ni associated with the primary NID */
 858                 lpni = lnet_peer_get_ni_locked(rtr, rtr->lp_primary_nid);
 859                 if (!lpni) {
 860                         CDEBUG(D_NET, "Expected to find an lpni for %s, but non found\n",
 861                                libcfs_nid2str(rtr->lp_primary_nid));
 862                         continue;
 863                 }
 864                 lnet_peer_ni_addref_locked(lpni);
 865
 866                 /* discover the router */
 867                 CDEBUG(D_NET, "discover %s, cpt = %d\n",
 868                        libcfs_nid2str(lpni->lpni_nid), cpt);
 869                 rc = lnet_discover_peer_locked(lpni, cpt, false);
 870
 871                 /* decrement ref count acquired by find_peer_ni_locked() */
 872                 lnet_peer_ni_decref_locked(lpni);
 873
 874                 if (!rc)
 875                         rtr->lp_rtrcheck_timestamp = now;
 876                 else
 877                         CERROR("Failed to discover router %s\n",
 878                                libcfs_nid2str(rtr->lp_primary_nid));
 879
 880                 /* NB dropped lock */
 881                 if (version != the_lnet.ln_routers_version) {
 882                         /* the routers list has changed */
 883                         goto rescan;
 884                 }
 885         }
 886
 887         if (the_lnet.ln_routing)
 888                 lnet_update_ni_status_locked();
 889
 890         lnet_net_unlock(cpt);
 891 }
 892
 893 void
 894 lnet_destroy_rtrbuf(struct lnet_rtrbuf *rb, int npages)
 895 {
 896         int sz = offsetof(struct lnet_rtrbuf, rb_kiov[npages]);
 897
 898         while (--npages >= 0)
 899                 __free_page(rb->rb_kiov[npages].kiov_page);
 900
 901         LIBCFS_FREE(rb, sz);
 902 }
 903
 904 static struct lnet_rtrbuf *
 905 lnet_new_rtrbuf(struct lnet_rtrbufpool *rbp, int cpt)
 906 {
 907         int            npages = rbp->rbp_npages;
 908         int            sz = offsetof(struct lnet_rtrbuf, rb_kiov[npages]);
 909         struct page   *page;
 910         struct lnet_rtrbuf *rb;
 911         int            i;
 912
 913         LIBCFS_CPT_ALLOC(rb, lnet_cpt_table(), cpt, sz);
 914         if (rb == NULL)
 915                 return NULL;
 916
 917         rb->rb_pool = rbp;
 918
 919         for (i = 0; i < npages; i++) {
 920                 page = cfs_page_cpt_alloc(lnet_cpt_table(), cpt,
 921                                           GFP_KERNEL | __GFP_ZERO);
 922                 if (page == NULL) {
 923                         while (--i >= 0)
 924                                 __free_page(rb->rb_kiov[i].kiov_page);
 925
 926                         LIBCFS_FREE(rb, sz);
 927                         return NULL;
 928                 }
 929
 930                 rb->rb_kiov[i].kiov_len = PAGE_SIZE;
 931                 rb->rb_kiov[i].kiov_offset = 0;
 932                 rb->rb_kiov[i].kiov_page = page;
 933         }
 934
 935         return rb;
 936 }
 937
 938 static void
 939 lnet_rtrpool_free_bufs(struct lnet_rtrbufpool *rbp, int cpt)
 940 {
 941         int npages = rbp->rbp_npages;
 942         struct lnet_rtrbuf *rb;
 943         struct list_head tmp;
 944
 945         if (rbp->rbp_nbuffers == 0) /* not initialized or already freed */
 946                 return;
 947
 948         INIT_LIST_HEAD(&tmp);
 949
 950         lnet_net_lock(cpt);
 951         list_splice_init(&rbp->rbp_msgs, &tmp);
 952         lnet_drop_routed_msgs_locked(&tmp, cpt);
 953         list_splice_init(&rbp->rbp_bufs, &tmp);
 954         rbp->rbp_req_nbuffers = 0;
 955         rbp->rbp_nbuffers = rbp->rbp_credits = 0;
 956         rbp->rbp_mincredits = 0;
 957         lnet_net_unlock(cpt);
 958
 959         /* Free buffers on the free list. */
 960         while (!list_empty(&tmp)) {
 961                 rb = list_entry(tmp.next, struct lnet_rtrbuf, rb_list);
 962                 list_del(&rb->rb_list);
 963                 lnet_destroy_rtrbuf(rb, npages);
 964         }
 965 }
 966
 967 static int
 968 lnet_rtrpool_adjust_bufs(struct lnet_rtrbufpool *rbp, int nbufs, int cpt)
 969 {
 970         struct list_head rb_list;
 971         struct lnet_rtrbuf *rb;
 972         int             num_rb;
 973         int             num_buffers = 0;
 974         int             old_req_nbufs;
 975         int             npages = rbp->rbp_npages;
 976
 977         lnet_net_lock(cpt);
 978         /* If we are called for less buffers than already in the pool, we
 979          * just lower the req_nbuffers number and excess buffers will be
 980          * thrown away as they are returned to the free list.  Credits
 981          * then get adjusted as well.
 982          * If we already have enough buffers allocated to serve the
 983          * increase requested, then we can treat that the same way as we
 984          * do the decrease. */
 985         num_rb = nbufs - rbp->rbp_nbuffers;
 986         if (nbufs <= rbp->rbp_req_nbuffers || num_rb <= 0) {
 987                 rbp->rbp_req_nbuffers = nbufs;
 988                 lnet_net_unlock(cpt);
 989                 return 0;
 990         }
 991         /* store the older value of rbp_req_nbuffers and then set it to
 992          * the new request to prevent lnet_return_rx_credits_locked() from
 993          * freeing buffers that we need to keep around */
 994         old_req_nbufs = rbp->rbp_req_nbuffers;
 995         rbp->rbp_req_nbuffers = nbufs;
 996         lnet_net_unlock(cpt);
 997
 998         INIT_LIST_HEAD(&rb_list);
 999
1000         /* allocate the buffers on a local list first.  If all buffers are
1001          * allocated successfully then join this list to the rbp buffer
1002          * list.  If not then free all allocated buffers. */
1003         while (num_rb-- > 0) {
1004                 rb = lnet_new_rtrbuf(rbp, cpt);
1005                 if (rb == NULL) {
1006                         CERROR("Failed to allocate %d route bufs of %d pages\n",
1007                                nbufs, npages);
1008
1009                         lnet_net_lock(cpt);
1010                         rbp->rbp_req_nbuffers = old_req_nbufs;
1011                         lnet_net_unlock(cpt);
1012
1013                         goto failed;
1014                 }
1015
1016                 list_add(&rb->rb_list, &rb_list);
1017                 num_buffers++;
1018         }
1019
1020         lnet_net_lock(cpt);
1021
1022         list_splice_tail(&rb_list, &rbp->rbp_bufs);
1023         rbp->rbp_nbuffers += num_buffers;
1024         rbp->rbp_credits += num_buffers;
1025         rbp->rbp_mincredits = rbp->rbp_credits;
1026         /* We need to schedule blocked msg using the newly
1027          * added buffers. */
1028         while (!list_empty(&rbp->rbp_bufs) &&
1029                !list_empty(&rbp->rbp_msgs))
1030                 lnet_schedule_blocked_locked(rbp);
1031
1032         lnet_net_unlock(cpt);
1033
1034         return 0;
1035
1036 failed:
1037         while (!list_empty(&rb_list)) {
1038                 rb = list_entry(rb_list.next, struct lnet_rtrbuf, rb_list);
1039                 list_del(&rb->rb_list);
1040                 lnet_destroy_rtrbuf(rb, npages);
1041         }
1042
1043         return -ENOMEM;
1044 }
1045
1046 static void
1047 lnet_rtrpool_init(struct lnet_rtrbufpool *rbp, int npages)
1048 {
1049         INIT_LIST_HEAD(&rbp->rbp_msgs);
1050         INIT_LIST_HEAD(&rbp->rbp_bufs);
1051
1052         rbp->rbp_npages = npages;
1053         rbp->rbp_credits = 0;
1054         rbp->rbp_mincredits = 0;
1055 }
1056
1057 void
1058 lnet_rtrpools_free(int keep_pools)
1059 {
1060         struct lnet_rtrbufpool *rtrp;
1061         int               i;
1062
1063         if (the_lnet.ln_rtrpools == NULL) /* uninitialized or freed */
1064                 return;
1065
1066         cfs_percpt_for_each(rtrp, i, the_lnet.ln_rtrpools) {
1067                 lnet_rtrpool_free_bufs(&rtrp[LNET_TINY_BUF_IDX], i);
1068                 lnet_rtrpool_free_bufs(&rtrp[LNET_SMALL_BUF_IDX], i);
1069                 lnet_rtrpool_free_bufs(&rtrp[LNET_LARGE_BUF_IDX], i);
1070         }
1071
1072         if (!keep_pools) {
1073                 cfs_percpt_free(the_lnet.ln_rtrpools);
1074                 the_lnet.ln_rtrpools = NULL;
1075         }
1076 }
1077
1078 static int
1079 lnet_nrb_tiny_calculate(void)
1080 {
1081         int     nrbs = LNET_NRB_TINY;
1082
1083         if (tiny_router_buffers < 0) {
1084                 LCONSOLE_ERROR_MSG(0x10c,
1085                                    "tiny_router_buffers=%d invalid when "
1086                                    "routing enabled\n", tiny_router_buffers);
1087                 return -EINVAL;
1088         }
1089
1090         if (tiny_router_buffers > 0)
1091                 nrbs = tiny_router_buffers;
1092
1093         nrbs /= LNET_CPT_NUMBER;
1094         return max(nrbs, LNET_NRB_TINY_MIN);
1095 }
1096
1097 static int
1098 lnet_nrb_small_calculate(void)
1099 {
1100         int     nrbs = LNET_NRB_SMALL;
1101
1102         if (small_router_buffers < 0) {
1103                 LCONSOLE_ERROR_MSG(0x10c,
1104                                    "small_router_buffers=%d invalid when "
1105                                    "routing enabled\n", small_router_buffers);
1106                 return -EINVAL;
1107         }
1108
1109         if (small_router_buffers > 0)
1110                 nrbs = small_router_buffers;
1111
1112         nrbs /= LNET_CPT_NUMBER;
1113         return max(nrbs, LNET_NRB_SMALL_MIN);
1114 }
1115
1116 static int
1117 lnet_nrb_large_calculate(void)
1118 {
1119         int     nrbs = LNET_NRB_LARGE;
1120
1121         if (large_router_buffers < 0) {
1122                 LCONSOLE_ERROR_MSG(0x10c,
1123                                    "large_router_buffers=%d invalid when "
1124                                    "routing enabled\n", large_router_buffers);
1125                 return -EINVAL;
1126         }
1127
1128         if (large_router_buffers > 0)
1129                 nrbs = large_router_buffers;
1130
1131         nrbs /= LNET_CPT_NUMBER;
1132         return max(nrbs, LNET_NRB_LARGE_MIN);
1133 }
1134
1135 int
1136 lnet_rtrpools_alloc(int im_a_router)
1137 {
1138         struct lnet_rtrbufpool *rtrp;
1139         int     nrb_tiny;
1140         int     nrb_small;
1141         int     nrb_large;
1142         int     rc;
1143         int     i;
1144
1145         if (!strcmp(forwarding, "")) {
1146                 /* not set either way */
1147                 if (!im_a_router)
1148                         return 0;
1149         } else if (!strcmp(forwarding, "disabled")) {
1150                 /* explicitly disabled */
1151                 return 0;
1152         } else if (!strcmp(forwarding, "enabled")) {
1153                 /* explicitly enabled */
1154         } else {
1155                 LCONSOLE_ERROR_MSG(0x10b, "'forwarding' not set to either "
1156                                    "'enabled' or 'disabled'\n");
1157                 return -EINVAL;
1158         }
1159
1160         nrb_tiny = lnet_nrb_tiny_calculate();
1161         if (nrb_tiny < 0)
1162                 return -EINVAL;
1163
1164         nrb_small = lnet_nrb_small_calculate();
1165         if (nrb_small < 0)
1166                 return -EINVAL;
1167
1168         nrb_large = lnet_nrb_large_calculate();
1169         if (nrb_large < 0)
1170                 return -EINVAL;
1171
1172         the_lnet.ln_rtrpools = cfs_percpt_alloc(lnet_cpt_table(),
1173                                                 LNET_NRBPOOLS *
1174                                                 sizeof(struct lnet_rtrbufpool));
1175         if (the_lnet.ln_rtrpools == NULL) {
1176                 LCONSOLE_ERROR_MSG(0x10c,
1177                                    "Failed to initialize router buffe pool\n");
1178                 return -ENOMEM;
1179         }
1180
1181         cfs_percpt_for_each(rtrp, i, the_lnet.ln_rtrpools) {
1182                 lnet_rtrpool_init(&rtrp[LNET_TINY_BUF_IDX], 0);
1183                 rc = lnet_rtrpool_adjust_bufs(&rtrp[LNET_TINY_BUF_IDX],
1184                                               nrb_tiny, i);
1185                 if (rc != 0)
1186                         goto failed;
1187
1188                 lnet_rtrpool_init(&rtrp[LNET_SMALL_BUF_IDX],
1189                                   LNET_NRB_SMALL_PAGES);
1190                 rc = lnet_rtrpool_adjust_bufs(&rtrp[LNET_SMALL_BUF_IDX],
1191                                               nrb_small, i);
1192                 if (rc != 0)
1193                         goto failed;
1194
1195                 lnet_rtrpool_init(&rtrp[LNET_LARGE_BUF_IDX],
1196                                   LNET_NRB_LARGE_PAGES);
1197                 rc = lnet_rtrpool_adjust_bufs(&rtrp[LNET_LARGE_BUF_IDX],
1198                                               nrb_large, i);
1199                 if (rc != 0)
1200                         goto failed;
1201         }
1202
1203         lnet_net_lock(LNET_LOCK_EX);
1204         the_lnet.ln_routing = 1;
1205         lnet_net_unlock(LNET_LOCK_EX);
1206         wake_up(&the_lnet.ln_mt_waitq);
1207         return 0;
1208
1209  failed:
1210         lnet_rtrpools_free(0);
1211         return rc;
1212 }
1213
1214 static int
1215 lnet_rtrpools_adjust_helper(int tiny, int small, int large)
1216 {
1217         int nrb = 0;
1218         int rc = 0;
1219         int i;
1220         struct lnet_rtrbufpool *rtrp;
1221
1222         /* If the provided values for each buffer pool are different than the
1223          * configured values, we need to take action. */
1224         if (tiny >= 0) {
1225                 tiny_router_buffers = tiny;
1226                 nrb = lnet_nrb_tiny_calculate();
1227                 cfs_percpt_for_each(rtrp, i, the_lnet.ln_rtrpools) {
1228                         rc = lnet_rtrpool_adjust_bufs(&rtrp[LNET_TINY_BUF_IDX],
1229                                                       nrb, i);
1230                         if (rc != 0)
1231                                 return rc;
1232                 }
1233         }
1234         if (small >= 0) {
1235                 small_router_buffers = small;
1236                 nrb = lnet_nrb_small_calculate();
1237                 cfs_percpt_for_each(rtrp, i, the_lnet.ln_rtrpools) {
1238                         rc = lnet_rtrpool_adjust_bufs(&rtrp[LNET_SMALL_BUF_IDX],
1239                                                       nrb, i);
1240                         if (rc != 0)
1241                                 return rc;
1242                 }
1243         }
1244         if (large >= 0) {
1245                 large_router_buffers = large;
1246                 nrb = lnet_nrb_large_calculate();
1247                 cfs_percpt_for_each(rtrp, i, the_lnet.ln_rtrpools) {
1248                         rc = lnet_rtrpool_adjust_bufs(&rtrp[LNET_LARGE_BUF_IDX],
1249                                                       nrb, i);
1250                         if (rc != 0)
1251                                 return rc;
1252                 }
1253         }
1254
1255         return 0;
1256 }
1257
1258 int
1259 lnet_rtrpools_adjust(int tiny, int small, int large)
1260 {
1261         /* this function doesn't revert the changes if adding new buffers
1262          * failed.  It's up to the user space caller to revert the
1263          * changes. */
1264
1265         if (!the_lnet.ln_routing)
1266                 return 0;
1267
1268         return lnet_rtrpools_adjust_helper(tiny, small, large);
1269 }
1270
1271 int
1272 lnet_rtrpools_enable(void)
1273 {
1274         int rc = 0;
1275
1276         if (the_lnet.ln_routing)
1277                 return 0;
1278
1279         if (the_lnet.ln_rtrpools == NULL)
1280                 /* If routing is turned off, and we have never
1281                  * initialized the pools before, just call the
1282                  * standard buffer pool allocation routine as
1283                  * if we are just configuring this for the first
1284                  * time. */
1285                 rc = lnet_rtrpools_alloc(1);
1286         else
1287                 rc = lnet_rtrpools_adjust_helper(0, 0, 0);
1288         if (rc != 0)
1289                 return rc;
1290
1291         lnet_net_lock(LNET_LOCK_EX);
1292         the_lnet.ln_routing = 1;
1293
1294         the_lnet.ln_ping_target->pb_info.pi_features &=
1295                 ~LNET_PING_FEAT_RTE_DISABLED;
1296         lnet_net_unlock(LNET_LOCK_EX);
1297
1298         return rc;
1299 }
1300
1301 void
1302 lnet_rtrpools_disable(void)
1303 {
1304         if (!the_lnet.ln_routing)
1305                 return;
1306
1307         lnet_net_lock(LNET_LOCK_EX);
1308         the_lnet.ln_routing = 0;
1309         the_lnet.ln_ping_target->pb_info.pi_features |=
1310                 LNET_PING_FEAT_RTE_DISABLED;
1311
1312         tiny_router_buffers = 0;
1313         small_router_buffers = 0;
1314         large_router_buffers = 0;
1315         lnet_net_unlock(LNET_LOCK_EX);
1316         lnet_rtrpools_free(1);
1317 }
1318
1319 static inline void
1320 lnet_notify_peer_down(struct lnet_ni *ni, lnet_nid_t nid)
1321 {
1322         if (ni->ni_net->net_lnd->lnd_notify_peer_down != NULL)
1323                 (ni->ni_net->net_lnd->lnd_notify_peer_down)(nid);
1324 }
1325
1326 /*
1327  * ni: local NI used to communicate with the peer
1328  * nid: peer NID
1329  * alive: true if peer is alive, false otherwise
1330  * reset: reset health value. This is requested by the LND.
1331  * when: notificaiton time.
1332  */
1333 int
1334 lnet_notify(struct lnet_ni *ni, lnet_nid_t nid, bool alive, bool reset,
1335             time64_t when)
1336 {
1337         struct lnet_peer_ni *lpni = NULL;
1338         time64_t now = ktime_get_seconds();
1339         int cpt;
1340
1341         LASSERT (!in_interrupt ());
1342
1343         CDEBUG (D_NET, "%s notifying %s: %s\n",
1344                 (ni == NULL) ? "userspace" : libcfs_nid2str(ni->ni_nid),
1345                 libcfs_nid2str(nid),
1346                 alive ? "up" : "down");
1347
1348         if (ni != NULL &&
1349             LNET_NIDNET(ni->ni_nid) != LNET_NIDNET(nid)) {
1350                 CWARN("Ignoring notification of %s %s by %s (different net)\n",
1351                       libcfs_nid2str(nid), alive ? "birth" : "death",
1352                       libcfs_nid2str(ni->ni_nid));
1353                 return -EINVAL;
1354         }
1355
1356         /* can't do predictions... */
1357         if (when > now) {
1358                 CWARN("Ignoring prediction from %s of %s %s "
1359                       "%lld seconds in the future\n",
1360                       (ni == NULL) ? "userspace" : libcfs_nid2str(ni->ni_nid),
1361                       libcfs_nid2str(nid), alive ? "up" : "down", when - now);
1362                 return -EINVAL;
1363         }
1364
1365         if (ni != NULL && !alive &&             /* LND telling me she's down */
1366             !auto_down) {                       /* auto-down disabled */
1367                 CDEBUG(D_NET, "Auto-down disabled\n");
1368                 return 0;
1369         }
1370
1371         /* must lock 0 since this is used for synchronization */
1372         lnet_net_lock(0);
1373
1374         if (the_lnet.ln_state != LNET_STATE_RUNNING) {
1375                 lnet_net_unlock(0);
1376                 return -ESHUTDOWN;
1377         }
1378
1379         lpni = lnet_find_peer_ni_locked(nid);
1380         if (lpni == NULL) {
1381                 /* nid not found */
1382                 lnet_net_unlock(0);
1383                 CDEBUG(D_NET, "%s not found\n", libcfs_nid2str(nid));
1384                 return 0;
1385         }
1386
1387         if (alive) {
1388                 if (reset)
1389                         lnet_set_healthv(&lpni->lpni_healthv,
1390                                          LNET_MAX_HEALTH_VALUE);
1391                 else
1392                         lnet_inc_healthv(&lpni->lpni_healthv);
1393         } else {
1394                 lnet_handle_remote_failure_locked(lpni);
1395         }
1396
1397         /* recalculate aliveness */
1398         alive = lnet_is_peer_ni_alive(lpni);
1399         lnet_net_unlock(0);
1400
1401         if (ni != NULL && !alive)
1402                 lnet_notify_peer_down(ni, lpni->lpni_nid);
1403
1404         cpt = lpni->lpni_cpt;
1405         lnet_net_lock(cpt);
1406         lnet_peer_ni_decref_locked(lpni);
1407         lnet_net_unlock(cpt);
1408
1409         return 0;
1410 }
1411 EXPORT_SYMBOL(lnet_notify);