lnet/klnds/gnilnd/gnilnd_stack.c

   1 /*
   2  * Copyright (C) 2012 Cray, Inc.
   3  *
   4  * Copyright (c) 2014, Intel Corporation.
   5  *
   6  *   Author: Nic Henke <nic@cray.com>
   7  *
   8  *   This file is part of Lustre, http://www.lustre.org.
   9  *
  10  *   Lustre is free software; you can redistribute it and/or
  11  *   modify it under the terms of version 2 of the GNU General Public
  12  *   License as published by the Free Software Foundation.
  13  *
  14  *   Lustre is distributed in the hope that it will be useful,
  15  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  *   GNU General Public License for more details.
  18  *
  19  *   You should have received a copy of the GNU General Public License
  20  *   along with Lustre; if not, write to the Free Software
  21  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  22  *
  23  */
  24 #include "gnilnd.h"
  25 #if defined(GNILND_USE_RCA)
  26 #include <rsms/rs_sm_states.h>
  27 #endif
  28 /* Advance all timeouts by nap_time seconds. */
  29 void
  30 kgnilnd_bump_timeouts(__u32 nap_time, char *reason)
  31 {
  32         int                     i;
  33         kgn_peer_t             *peer;
  34         kgn_conn_t             *conn;
  35         kgn_tx_t               *tx;
  36         kgn_device_t           *dev;
  37         kgn_dgram_t            *dgram;
  38
  39         LCONSOLE_INFO("%s: bumping all timeouts by %ds\n", reason, nap_time);
  40
  41         LASSERTF(GNILND_IS_QUIESCED, "gnilnd not quiesced %d != %d\n",
  42                  atomic_read(&kgnilnd_data.kgn_nquiesce),
  43                  atomic_read(&kgnilnd_data.kgn_nthreads));
  44
  45         /* requiring that the threads are paused ensures a couple of things:
  46          * - combined code paths for stack reset and quiesce event as stack reset
  47          *   runs with the threads paused
  48          * - prevents traffic to the Gemini during a quiesce period
  49          * - reduces the locking requirements
  50         */
  51
  52         for (i = 0; i < *kgnilnd_tunables.kgn_peer_hash_size; i++) {
  53                 list_for_each_entry(peer, &kgnilnd_data.kgn_peers[i], gnp_list) {
  54
  55                         /* we can reconnect again at any time */
  56                         peer->gnp_reconnect_time = jiffies;
  57                         /* reset now that network is healthy */
  58                         peer->gnp_reconnect_interval = 0;
  59                         /* tell LNet dude is still alive */
  60                         kgnilnd_peer_alive(peer);
  61
  62                         list_for_each_entry(tx, &peer->gnp_tx_queue, tx_list) {
  63                                 tx->tx_qtime = jiffies;
  64                         }
  65
  66                         list_for_each_entry(conn, &peer->gnp_conns, gnc_list) {
  67                                 unsigned long           timeout;
  68
  69                                 timeout = cfs_time_seconds(conn->gnc_timeout);
  70
  71                                 /* bump last_rx/last_rx_cq on all conns - including
  72                                  * closed ones, this will have the effect of
  73                                  * bumping the purgatory timers for those */
  74                                 conn->gnc_last_rx = conn->gnc_last_rx_cq = jiffies;
  75
  76                                 /* we don't timeout based on old gnc_last_tx, so
  77                                  * we'll back it up and schedule the conn to trigger
  78                                  * a NOOP */
  79                                 conn->gnc_last_tx = jiffies - timeout;
  80                                 if (conn->gnc_state != GNILND_CONN_DONE)
  81                                 kgnilnd_schedule_conn(conn);
  82                         }
  83                 }
  84         }
  85
  86         for (i = 0; i < kgnilnd_data.kgn_ndevs; i++) {
  87                 dev = &kgnilnd_data.kgn_devices[i];
  88                 for (i = 0; i < (*kgnilnd_tunables.kgn_peer_hash_size - 1); i++) {
  89                         list_for_each_entry(dgram, &dev->gnd_dgrams[i], gndg_list) {
  90                                 dgram->gndg_post_time = jiffies;
  91                         }
  92                 }
  93         }
  94 }
  95
  96 /* Quiesce or wake up the stack.  The caller must hold the kgn_quiesce_sem semaphore
  97  * on entry, which holds off any pending stack shutdown.   */
  98 void
  99 kgnilnd_quiesce_wait(char *reason)
 100 {
 101         int             i;
 102
 103         if (kgnilnd_data.kgn_quiesce_trigger) {
 104                 unsigned long   quiesce_deadline, quiesce_to;
 105                 /* FREEZE TAG!!!! */
 106
 107                 /* morning sunshine */
 108                 spin_lock(&kgnilnd_data.kgn_reaper_lock);
 109                 wake_up_all(&kgnilnd_data.kgn_reaper_waitq);
 110                 spin_unlock(&kgnilnd_data.kgn_reaper_lock);
 111
 112                 for (i = 0; i < kgnilnd_data.kgn_ndevs; i++) {
 113                         kgn_device_t *dev = &kgnilnd_data.kgn_devices[i];
 114
 115                         wake_up_all(&dev->gnd_waitq);
 116                         wake_up_all(&dev->gnd_dgram_waitq);
 117                         wake_up_all(&dev->gnd_dgping_waitq);
 118                 }
 119
 120                 kgnilnd_wakeup_rca_thread();
 121
 122                 /* we'll wait for 10x the timeout for the threads to pause */
 123                 quiesce_to = cfs_time_seconds(*kgnilnd_tunables.kgn_timeout * 10);
 124                 quiesce_deadline = (long) jiffies + quiesce_to;
 125
 126                 /* wait for everyone to check-in as quiesced */
 127                 i = 1;
 128                 while (!GNILND_IS_QUIESCED) {
 129                         i++;
 130                         LCONSOLE((((i) & (-i)) == i) ? D_WARNING : D_NET,
 131                                  "%s: Waiting for %d threads to pause\n",
 132                                  reason,
 133                                  atomic_read(&kgnilnd_data.kgn_nthreads) -
 134                                  atomic_read(&kgnilnd_data.kgn_nquiesce));
 135                         CFS_RACE(CFS_FAIL_GNI_QUIESCE_RACE);
 136                         cfs_pause(cfs_time_seconds(1 * i));
 137
 138                         LASSERTF(quiesce_deadline > jiffies,
 139                                  "couldn't quiesce threads in %lu seconds, falling over now\n",
 140                                  cfs_duration_sec(quiesce_to));
 141                 }
 142
 143                 LCONSOLE_WARN("%s: All threads paused!\n", reason);
 144                 /* XXX Nic: Is there a set of counters we can grab here to
 145                  * ensure that there is no traffic until quiesce is over ?*/
 146         } else {
 147                 /* GO! GO! GO! */
 148
 149                 for (i = 0; i < kgnilnd_data.kgn_ndevs; i++) {
 150                         kgn_device_t *dev = &kgnilnd_data.kgn_devices[i];
 151                         kgnilnd_schedule_dgram(dev);
 152                 }
 153
 154                 /* wait for everyone to check-in as running - they will be spinning
 155                  * and looking, so no need to poke any waitq */
 156                 i = 1;
 157                 while (atomic_read(&kgnilnd_data.kgn_nquiesce) > 0) {
 158                         i++;
 159                         LCONSOLE((((i) & (-i)) == i) ? D_WARNING : D_NET,
 160                                  "%s: Waiting for %d threads to wake up\n",
 161                                   reason,
 162                                   atomic_read(&kgnilnd_data.kgn_nquiesce));
 163                         cfs_pause(cfs_time_seconds(1 * i));
 164                 }
 165
 166                 LCONSOLE_WARN("%s: All threads awake!\n", reason);
 167         }
 168 }
 169
 170 /* Reset the stack.  */
 171 void
 172 kgnilnd_reset_stack(void)
 173 {
 174         int              i, rc = 0;
 175         kgn_net_t       *net;
 176         kgn_peer_t      *peer, *peerN;
 177         LIST_HEAD        (souls);
 178         char            *reason = "critical hardware error";
 179         __u32            seconds;
 180         unsigned long    start, end;
 181         ENTRY;
 182
 183         /* Race with del_peer and its atomics */
 184         CFS_RACE(CFS_FAIL_GNI_RACE_RESET);
 185
 186         if (kgnilnd_data.kgn_init != GNILND_INIT_ALL) {
 187                 CERROR("can't reset the stack, gnilnd is not initialized\n");
 188                 RETURN_EXIT;
 189         }
 190
 191         /* First make sure we are not already quiesced - we panic if so,
 192          * as that could leave software in a bad state */
 193         LASSERTF(kgnilnd_data.kgn_quiesce_trigger == GNILND_QUIESCE_IDLE,
 194                 "can't reset the stack, already doing so: trigger %d\n",
 195                  kgnilnd_data.kgn_quiesce_trigger);
 196
 197         set_mb(kgnilnd_data.kgn_quiesce_trigger, GNILND_QUIESCE_RESET);
 198
 199         /* wake up the dgram waitq thread - but after trigger set to make sure it
 200          * goes into quiesce */
 201         CFS_RACE(CFS_FAIL_GNI_WC_DGRAM_FREE);
 202         /* same for scheduler that is dropping state transitiosn */
 203         CFS_RACE(CFS_FAIL_GNI_DROP_CLOSING);
 204         CFS_RACE(CFS_FAIL_GNI_DROP_DESTROY_EP);
 205
 206         kgnilnd_quiesce_wait(reason);
 207
 208         start = jiffies;
 209
 210         kgnilnd_data.kgn_in_reset = 1;
 211         kgnilnd_data.kgn_nresets++;
 212         LCONSOLE_WARN("%s: resetting all resources (count %d)\n",
 213                       reason, kgnilnd_data.kgn_nresets);
 214
 215         for (i = 0; i < *kgnilnd_tunables.kgn_net_hash_size; i++) {
 216                 list_for_each_entry(net, &kgnilnd_data.kgn_nets[i], gnn_list) {
 217                         rc = kgnilnd_cancel_net_dgrams(net);
 218                         LASSERTF(rc == 0, "couldn't cleanup datagrams: %d\n", rc);
 219                 }
 220         }
 221
 222         /* error -ENOTRECOVERABLE is stack reset */
 223         kgnilnd_del_conn_or_peer(NULL, LNET_NID_ANY, GNILND_DEL_CONN, -ENOTRECOVERABLE);
 224
 225         for (i = 0; i < kgnilnd_data.kgn_ndevs; i++) {
 226                 kgn_device_t    *dev = &kgnilnd_data.kgn_devices[i];
 227                 kgnilnd_cancel_wc_dgrams(dev);
 228                 kgnilnd_wait_for_canceled_dgrams(dev);
 229         }
 230
 231         /* manually do some conn processing ala kgnilnd_process_conns */
 232         for (i = 0; i < kgnilnd_data.kgn_ndevs; i++) {
 233                 kgn_device_t    *dev = &kgnilnd_data.kgn_devices[i];
 234                 kgn_conn_t      *conn;
 235                 int              conn_sched;
 236
 237                 /* go find all the closed conns that need to be nuked - the
 238                  * scheduler thread isn't running to do this for us */
 239
 240                 CDEBUG(D_NET, "will try to clear up %d ready_conns\n",
 241                         kgnilnd_count_list(&dev->gnd_ready_conns));
 242
 243                 /* use while/list_first_entry loop to ensure we can handle any
 244                  * DESTROY_EP conns added from kgnilnd_complete_closed_conn */
 245                 while (!list_empty(&dev->gnd_ready_conns)) {
 246                         conn = list_first_entry(&dev->gnd_ready_conns,
 247                                                 kgn_conn_t, gnc_schedlist);
 248                         conn_sched = xchg(&conn->gnc_scheduled, GNILND_CONN_PROCESS);
 249
 250                         LASSERTF(conn_sched != GNILND_CONN_IDLE &&
 251                                  conn_sched != GNILND_CONN_PROCESS,
 252                                  "conn %p on ready list but in bad state: %d\n",
 253                                  conn, conn_sched);
 254
 255                         list_del_init(&conn->gnc_schedlist);
 256
 257                         if (conn->gnc_state == GNILND_CONN_CLOSING) {
 258                                 /* bump to CLOSED to fake out send of CLOSE */
 259                                 conn->gnc_state = GNILND_CONN_CLOSED;
 260                                 conn->gnc_close_sent = 1;
 261                         }
 262
 263                         if (conn->gnc_state == GNILND_CONN_DESTROY_EP) {
 264                                 kgnilnd_destroy_conn_ep(conn);
 265                         } else {
 266                                 kgnilnd_complete_closed_conn(conn);
 267                         }
 268
 269                         /* there really shouldn't be any other states here -
 270                          * they would have been cleared out in the del_peer_or_conn or the dgram
 271                          * aborts above.
 272                          * there is an LASSERTF in kgnilnd_complete_closed_conn that will take
 273                          * care of catching anything else for us */
 274
 275                         kgnilnd_schedule_process_conn(conn, -1);
 276
 277                         kgnilnd_conn_decref(conn);
 278                 }
 279         }
 280
 281         /* don't let the little weasily purgatory conns hide from us */
 282         for (i = 0; i < *kgnilnd_tunables.kgn_peer_hash_size; i++) {
 283                 list_for_each_entry_safe(peer, peerN, &kgnilnd_data.kgn_peers[i], gnp_list) {
 284                         kgn_conn_t       *conn, *connN;
 285
 286                         list_for_each_entry_safe(conn, connN, &peer->gnp_conns, gnc_list) {
 287                                 kgnilnd_detach_purgatory_locked(conn, &souls);
 288                         }
 289                 }
 290         }
 291
 292         CDEBUG(D_NET, "about to release %d purgatory entries\n",
 293                 kgnilnd_count_list(&souls));
 294
 295         kgnilnd_release_purgatory_list(&souls);
 296
 297         /* validate we are now clean */
 298         for (i = 0; i < kgnilnd_data.kgn_ndevs; i++) {
 299                 kgn_device_t    *dev = &kgnilnd_data.kgn_devices[i];
 300
 301                 /* now all the cons/mboxes should be cleaned up, including purgatory
 302                  * so go through and release the MDDs for our persistent PHYS fma_blks
 303                  */
 304                 kgnilnd_unmap_fma_blocks(dev);
 305
 306                 LASSERTF(atomic_read(&dev->gnd_nfmablk) == 0,
 307                         "reset failed: fma blocks still live %d\n",
 308                         atomic_read(&dev->gnd_nfmablk));
 309
 310                 LASSERTF(atomic_read(&dev->gnd_neps) == 0,
 311                         "reset failed: EP handles still live %d\n",
 312                         atomic_read(&dev->gnd_neps));
 313         }
 314
 315         LASSERTF(atomic_read(&kgnilnd_data.kgn_nconns) == 0,
 316                 "reset failed: conns left %d\n",
 317                 atomic_read(&kgnilnd_data.kgn_nconns));
 318
 319         /* fine to have peers left - they are waiting for new conns
 320          * but should not be holding any open HW resources */
 321
 322         /* like the last part of kgnilnd_base_shutdown() */
 323
 324         CFS_RACE(CFS_FAIL_GNI_SR_DOWN_RACE);
 325
 326         for (i = 0; i < kgnilnd_data.kgn_ndevs; i++) {
 327                 kgnilnd_dev_fini(&kgnilnd_data.kgn_devices[i]);
 328         }
 329
 330         /* no need to free and recreate the TX descriptors
 331          * we nuked all the ones that could be using HW resources in
 332          * kgnilnd_close_matching_conns and asserted it worked in
 333          * kgnilnd_dev_fini */
 334
 335         /* At this point, all HW is torn down, start to reset */
 336
 337         /* only reset our known devs */
 338         for (i = 0; i < kgnilnd_data.kgn_ndevs; i++) {
 339                 kgn_device_t    *dev = &kgnilnd_data.kgn_devices[i];
 340                 rc = kgnilnd_dev_init(dev);
 341                 LASSERTF(rc == 0, "dev_init failed for dev %d\n", i);
 342                 kgnilnd_map_phys_fmablk(dev);
 343                 LASSERTF(rc == 0, "map_phys_fmablk failed for dev %d\n", i);
 344                 rc = kgnilnd_setup_wildcard_dgram(dev);
 345                 LASSERTF(rc == 0, "couldnt setup datagrams on dev %d: %d\n",
 346                         i, rc);
 347         }
 348
 349         /* Now the fun restarts... - release the hounds! */
 350
 351         end = jiffies;
 352         seconds = cfs_duration_sec((long)end - start);
 353         kgnilnd_bump_timeouts(seconds, reason);
 354
 355         kgnilnd_data.kgn_in_reset = 0;
 356         set_mb(kgnilnd_data.kgn_quiesce_trigger, GNILND_QUIESCE_IDLE);
 357         kgnilnd_quiesce_wait(reason);
 358         LCONSOLE_WARN("%s reset of all hardware resources\n",
 359                 rc ? "failed" : "successful");
 360
 361         RETURN_EXIT;
 362 }
 363
 364 /* A thread that handles quiece and reset hardware events.
 365  * We do the same thing regardless of which device reported the event. */
 366 int
 367 kgnilnd_ruhroh_thread(void *arg)
 368 {
 369         int                i = 1;
 370         DEFINE_WAIT(wait);
 371
 372         cfs_block_allsigs();
 373         set_user_nice(current, *kgnilnd_tunables.kgn_nice);
 374         kgnilnd_data.kgn_ruhroh_running = 1;
 375
 376         while (1) {
 377
 378                 /* Block until there's a request..  A reset request could come in
 379                  * while we're handling a quiesce one, or vice versa.
 380                  * Keep processing requests until there are none.*/
 381                 prepare_to_wait(&kgnilnd_data.kgn_ruhroh_waitq, &wait, TASK_INTERRUPTIBLE);
 382                 while (!(kgnilnd_data.kgn_ruhroh_shutdown ||
 383                                 kgnilnd_data.kgn_needs_reset || kgnilnd_data.kgn_needs_pause))
 384                         schedule();
 385                 finish_wait(&kgnilnd_data.kgn_ruhroh_waitq, &wait);
 386
 387                /* Exit if the driver is shutting down. */
 388                 if (kgnilnd_data.kgn_ruhroh_shutdown)
 389                         break;
 390
 391                 /* Serialize with driver startup and shutdown. */
 392                 mutex_lock(&kgnilnd_data.kgn_quiesce_mutex);
 393
 394                CDEBUG(D_NET, "trigger %d reset %d to_bump %d pause %d\n",
 395                         kgnilnd_data.kgn_quiesce_trigger,
 396                         kgnilnd_data.kgn_needs_reset,
 397                         kgnilnd_data.kgn_bump_info_rdy,
 398                         kgnilnd_data.kgn_needs_pause);
 399
 400                 /* Do we need to do a pause/quiesce? */
 401                 if (kgnilnd_data.kgn_needs_pause) {
 402
 403                         /* Pause all other kgnilnd threads. */
 404                         set_mb(kgnilnd_data.kgn_quiesce_trigger, GNILND_QUIESCE_HW_QUIESCE);
 405                         kgnilnd_quiesce_wait("hardware quiesce flag");
 406
 407                         /* If the hardware quiesce flag is set, wait for it to clear.
 408                          * This should happen relatively quickly, so we wait for it.
 409                          * This will hold up the eventd thread, but on everything but
 410                          * the simulator, this is ok-- there is one thread per core.
 411                          *
 412                          * Handle (possibly multiple) quiesce events while we wait. The
 413                          * memory barrier ensures that the core doesn't start fetching
 414                          * kgn_bump_info_rdy before it fetches kgn_needs_pause, and
 415                          * matches the second mb in kgnilnd_quiesce_end_callback(). */
 416                         smp_rmb();
 417                         while (kgnilnd_hw_in_quiesce() || kgnilnd_data.kgn_bump_info_rdy) {
 418
 419                                 i++;
 420                                 LCONSOLE((((i) & (-i)) == i) ? D_WARNING : D_NET,
 421                                                 "Waiting for hardware quiesce flag to clear\n");
 422                                 cfs_pause(cfs_time_seconds(1 * i));
 423
 424                                 /* If we got a quiesce event with bump info, DO THE BUMP!. */
 425                                 if (kgnilnd_data.kgn_bump_info_rdy) {
 426                                         /* reset console rate limiting for each event */
 427                                         i = 1;
 428
 429                                         /* Make sure the core doesn't start fetching
 430                                          * kgni_quiesce_seconds until after it sees
 431                                          * kgn_bump_info_rdy set.  This is the match to the
 432                                          * first mb in kgnilnd_quiesce_end_callback(). */
 433                                         smp_rmb();
 434                                         (void) kgnilnd_bump_timeouts(kgnilnd_data.kgn_quiesce_secs,
 435                                                                "hardware quiesce callback");
 436                                         set_mb(kgnilnd_data.kgn_quiesce_secs, 0);
 437                                         set_mb(kgnilnd_data.kgn_bump_info_rdy, 0);
 438                                 }
 439                       }
 440
 441                         /* Reset the kgn_needs_pause flag before coming out of
 442                          * the pause.  This ordering avoids a race with the
 443                          * setting of this flag in kgnilnd_pause_threads().  */
 444                         set_mb(kgnilnd_data.kgn_needs_pause, 0);
 445
 446                         /* ok, let the kids back into the pool */
 447                         set_mb(kgnilnd_data.kgn_quiesce_trigger, GNILND_QUIESCE_IDLE);
 448                         kgnilnd_quiesce_wait("hardware quiesce");
 449                 }
 450
 451                 /* Do a stack reset if needed. */
 452                 if (kgnilnd_data.kgn_needs_reset) {
 453                         kgnilnd_reset_stack();
 454                         set_mb(kgnilnd_data.kgn_needs_reset, 0);
 455                 }
 456
 457                 mutex_unlock(&kgnilnd_data.kgn_quiesce_mutex);
 458         }
 459
 460         kgnilnd_data.kgn_ruhroh_running = 0;
 461         return 0;
 462 }
 463
 464 /* Set pause request flag.  Any functions that
 465  * call this one are responsible for ensuring that
 466  * variables they set up are visible on other cores before
 467  * this flag setting.  This executes in interrupt or kernel
 468  * thread context.  */
 469 void
 470 kgnilnd_pause_threads(void)
 471 {
 472         /* only device 0 gets the handle, see kgnilnd_dev_init */
 473         kgn_device_t  *dev = &kgnilnd_data.kgn_devices[0];
 474         LASSERTF(dev != NULL, "dev 0 is NULL\n");
 475
 476         /* If we're currently in a pause triggered by the pause flag,
 477          * there's no need to set it again.  We clear the kgn_needs_pause
 478          * flag before we reset kgn_quiesce_trigger to avoid a race.  The
 479          * read memory barrier matches the setmb() on the trigger in
 480          * kgnilnd_ruhroh_task().                                       */
 481         smp_rmb();
 482         if (!(kgnilnd_data.kgn_quiesce_trigger == GNILND_QUIESCE_HW_QUIESCE &&
 483                         GNILND_IS_QUIESCED)) {
 484                  CDEBUG(D_NET, "requesting thread pause\n");
 485
 486                 kgnilnd_data.kgn_needs_pause = 1;
 487
 488                 wake_up(&kgnilnd_data.kgn_ruhroh_waitq);
 489         } else {
 490             CDEBUG(D_NET, "thread pause already underway\n");
 491         }
 492 }
 493
 494 /* Return non-zero if the GNI hardware quiesce flag is set */
 495 int
 496 kgnilnd_hw_in_quiesce(void)
 497 {
 498         /* only device 0 gets the handle, see kgnilnd_dev_init */
 499         kgn_device_t      *dev0 = &kgnilnd_data.kgn_devices[0];
 500
 501         LASSERTF(dev0 != NULL, "dev 0 is NULL\n");
 502
 503         smp_rmb();
 504         return kgnilnd_get_quiesce_status(dev0->gnd_handle) != 0;
 505 }
 506
 507
 508 /* If the GNI hardware quiesce flag is set, initiate our pause and
 509  * return non-zero.  Also return non-zero if the stack is shutting down. */
 510 int
 511 kgnilnd_check_hw_quiesce(void)
 512 {
 513         if (likely(!kgnilnd_hw_in_quiesce()))
 514                 return 0;
 515
 516         if (!kgnilnd_data.kgn_ruhroh_shutdown) {
 517                 CDEBUG(D_NET, "initiating thread pause\n");
 518                 kgnilnd_pause_threads();
 519         } else {
 520                 CDEBUG(D_NET, "thread pause bypassed because of shutdown\n");
 521         }
 522
 523         return 1;
 524 }
 525
 526 /* Callback from kngi with the quiesce duration.  This executes
 527  * in interrupt context.                                        */
 528 void
 529 kgnilnd_quiesce_end_callback(gni_nic_handle_t nic_handle, uint64_t msecs)
 530 {
 531         /* only device 0 gets the handle, see kgnilnd_dev_init */
 532         kgn_device_t  *dev = &kgnilnd_data.kgn_devices[0];
 533         LASSERTF(dev != NULL, "dev 0 is NULL\n");
 534
 535         if (!kgnilnd_data.kgn_ruhroh_shutdown) {
 536
 537                 CDEBUG(D_NET, "requesting timeout bump by "LPD64" msecs\n", msecs);
 538
 539                 /* Save the bump interval and request the bump.
 540                  * The memory barrier ensures that the interval is in place before
 541                  * the bump flag can be seen (in case a core is already running the
 542                  * ruhroh task), and that the bump request flag in place before
 543                  * the pause request can be seen (to ensure a core doesn't miss the bump
 544                  * request flag).       */
 545                 /* If another callback occurred before the ruhroh task
 546                  * finished processing the first bump request, we'd over-write its info.
 547                  * Nic says that callbacks occur so slowly that this isn't an issue.    */
 548                 set_mb(kgnilnd_data.kgn_quiesce_secs, msecs / MSEC_PER_SEC);
 549                 set_mb(kgnilnd_data.kgn_bump_info_rdy, 1);
 550                 kgnilnd_pause_threads();
 551         } else {
 552                 CDEBUG(D_NET, "timeout bump bypassed because of shutdown\n");
 553         }
 554 }
 555
 556 void
 557 kgnilnd_critical_error(struct gni_err *err_handle)
 558 {
 559         /* only device 0 gets the handle, see kgnilnd_dev_init */
 560         kgn_device_t  *dev = &kgnilnd_data.kgn_devices[0];
 561         LASSERTF(dev != NULL, "dev 0 is NULL\n");
 562
 563         if (!kgnilnd_data.kgn_ruhroh_shutdown) {
 564                 CDEBUG(D_NET, "requesting stack reset\n");
 565                 kgnilnd_data.kgn_needs_reset = 1;
 566                 wake_up(&kgnilnd_data.kgn_ruhroh_waitq);
 567         } else {
 568                 CDEBUG(D_NET, "stack reset bypassed because of shutdown\n");
 569         }
 570 }
 571
 572 #if defined(GNILND_USE_RCA)
 573 #include <krca_lib.h>
 574 #define RCA_EVENTS 3
 575 /* RCA ticket is needed for krca_wakeup_wait_event() */
 576 static krca_ticket_t rca_krt = KRCA_NULL_TICKET;
 577 struct rcadata {
 578         rca_ticket_t ticket;
 579         int subscribed;
 580         rs_event_code_t ec;
 581 };
 582 static struct rcadata rd[RCA_EVENTS] = {
 583         {0, 0, ec_node_unavailable},
 584         {0, 0, ec_node_available},
 585         {0, 0, ec_node_failed}
 586 };
 587
 588 /* thread for receiving rca events */
 589 int
 590 kgnilnd_rca(void *arg)
 591 {
 592         int        i, rc;
 593         int        retry_count;
 594         rs_event_t event;
 595         lnet_nid_t nid;
 596
 597         cfs_block_allsigs();
 598
 599         /* all gnilnd threads need to run fairly urgently */
 600         set_user_nice(current, *kgnilnd_tunables.kgn_nice);
 601
 602         /*
 603          * Register our service with RCA and subscribe to events
 604          * of interest.
 605          */
 606         rca_krt = KRCA_NULL_TICKET;
 607         rc = krca_register(&rca_krt, RCA_SVCTYPE_GNILND, current->pid, 0);
 608         if (rc < 0) {
 609                 CNETERR("krca_register(%x) returned %d\n", current->pid, rc);
 610                 goto done;
 611         }
 612
 613         for (i = 0; i < RCA_EVENTS; i++) {
 614                 retry_count = 0;
 615 subscribe_retry:
 616                 rc = krca_subscribe(&rca_krt, rd[i].ec, RCA_RX_SVC_ANY,
 617                                     &rd[i].ticket);
 618
 619                 if ((rc == -EINTR) && !retry_count) {
 620                         retry_count++;
 621                         CNETERR("krca_subscribe returned %d - retrying\n", rc);
 622                         goto subscribe_retry;
 623                 }
 624
 625                 if (rc < 0) {
 626                         CNETERR("rca subscription failed (%d)\n", rc);
 627                         goto done;
 628                 }
 629
 630                 rd[i].subscribed = 1;
 631         }
 632
 633         while (!kgnilnd_data.kgn_shutdown) {
 634                 if (unlikely(kgnilnd_data.kgn_quiesce_trigger)) {
 635                         KGNILND_SPIN_QUIESCE;
 636                 }
 637                 /* wait here for a subscribed event */
 638                 rc = krca_wait_event(&rca_krt);
 639
 640                 /* RCA return values:
 641                  * 0 indicates krca_wakeup_wait_event caused krca_wait_event
 642                  *   return.
 643                  * -ERESTARTSYS indicates krca_wait_event returned because of a
 644                  *   signal.
 645                  * -ENOSPC indicates no space available to create an rcad_reg_t
 646                  * 1 indicates a message is waiting.
 647                  */
 648                 if (rc <= 0) {
 649                         continue;
 650                 }
 651
 652                 if (krca_get_message(&rca_krt, &event) == 0) {
 653                         int node_down = GNILND_RCA_NODE_UNKNOWN;
 654                         rs_state_t state;
 655                         LIST_HEAD(zombies);
 656
 657                         /* Compute nodes don't care about other compute nodes
 658                          * so we don't need to create a peer.
 659                          */
 660                         if (GNILND_COMPUTE &&
 661                             !RSN_GET_FLD(event.ev_gen.svid_node.rs_node_flat,
 662                                         IS_SVC)) {
 663                                 continue;
 664                         }
 665
 666                         /* Only care about compute and service nodes not GPUs */
 667                         if (RSN_GET_FLD(event.ev_gen.svid_node.rs_node_flat,
 668                                         TYPE) != rt_node) {
 669                                 continue;
 670                         }
 671
 672                         switch (event.ev_id) {
 673                         case ec_node_available:
 674                                 CDEBUG(D_INFO, "ec_node_available\n");
 675                                 node_down = GNILND_RCA_NODE_UP;
 676                                 break;
 677                         case ec_node_failed:
 678                                 CDEBUG(D_INFO, "ec_node_failed\n");
 679                                 if (event.ev_len > 0) {
 680                                         CDEBUG(D_ERROR,
 681                                                 "ec_node_failed ignored\n");
 682                                         break;
 683                                 }
 684                                 node_down = GNILND_RCA_NODE_DOWN;
 685                                 break;
 686                         case ec_node_unavailable:
 687                                 state = RSN_GET_FLD(event.ev_gen.svid_node.rsn_intval, STATE);
 688
 689                                 CDEBUG(D_INFO, "ec_node_unavailable\n");
 690
 691                                 /*
 692                                  * Ignore overloaded ec_node_unavailable events
 693                                  * generated by 'xtcli set_reserve'.
 694                                  */
 695                                 if (RS_GET_CS_STATE(state) == RS_CS_READY) {
 696                                         CDEBUG(D_INFO, "ignoring "
 697                                                 "ec_node_unavailable event with"
 698                                                 " RS_CS_READY state\n");
 699                                         break;
 700                                 }
 701                                 node_down = GNILND_RCA_NODE_DOWN;
 702                                 break;
 703                         default:
 704                                 CDEBUG(D_INFO, "unknown event\n");
 705                                 break;
 706                         }
 707
 708                         /* if we get an event we don't know about, just go ahead
 709                          * and wait for another event */
 710                         if (node_down == GNILND_RCA_NODE_UNKNOWN) {
 711                                 continue;
 712                         }
 713
 714                         nid = RSN_GET_FLD(event.ev_gen.svid_node.rs_node_flat,
 715                                           NID);
 716                         CDEBUG(D_INFO,"kgnilnd_rca() reporting nid %d %s\n",
 717                                (int)nid, node_down ? "down" : "up");
 718                         kgnilnd_report_node_state(nid, node_down);
 719
 720                 } else {
 721                         CNETERR("krca_get_message failed\n");
 722                 }
 723         }
 724
 725 done:
 726         CDEBUG(D_INFO, "done\n");
 727
 728         for (i = 0; i < RCA_EVENTS; i++) {
 729                 if (rd[i].subscribed) {
 730                         rc = krca_unsubscribe(&rca_krt, rd[i].ticket);
 731
 732                         if (rc) {
 733                                 CNETERR("rca unsubscribe failed (%d)\n", rc);
 734                         }
 735
 736                         rd[i].subscribed = 0;
 737                 }
 738         }
 739
 740         krca_unregister(&rca_krt);
 741         kgnilnd_thread_fini();
 742         return 0;
 743
 744 }
 745
 746 int
 747 kgnilnd_start_rca_thread(void)
 748 {
 749         return kgnilnd_thread_start(kgnilnd_rca, NULL, "kgnilnd_rca", 0);
 750 }
 751
 752 void
 753 kgnilnd_wakeup_rca_thread(void)
 754 {
 755         int ret;
 756
 757         ret = krca_wakeup_wait_event(&rca_krt);
 758
 759         if (ret) {
 760                 CDEBUG(D_ERROR, "krca_wakeup_wait_event failed\n");
 761         }
 762 }
 763
 764 int
 765 kgnilnd_get_node_state(__u32 nid)
 766 {
 767         int i;
 768         int rc = GNILND_RCA_NODE_UNKNOWN;
 769         int ret;
 770         rs_node_array_t nlist;
 771         rs_node_t       *na = NULL;
 772
 773         if ((ret = krca_get_sysnodes(&nlist)) < 0) {
 774                 CDEBUG(D_NETERROR, "krca_get_sysnodes failed %d\n", ret);
 775                 goto ns_done;
 776         }
 777
 778         na = nlist.na_ids;
 779
 780         for (i = 0; i < nlist.na_len; i++) {
 781                 if ((rca_nid_t)RSN_GET_FLD(na[i].rs_node_flat, NID) == nid) {
 782                         rc = RSN_GET_FLD(na[i].rs_node_flat, STATE) == RS_CS_READY ?
 783                                 GNILND_RCA_NODE_UP : GNILND_RCA_NODE_DOWN;
 784                         break;
 785                 }
 786         }
 787
 788 ns_done:
 789         kfree(na);
 790         CDEBUG(D_NET, "nid %d rc %d (0=up)\n", nid, rc);
 791         return rc;
 792 }
 793
 794 #else /* GNILND_USE_RCA */
 795
 796 int
 797 kgnilnd_start_rca_thread(void)
 798 {
 799         return 0;
 800 }
 801
 802 void
 803 kgnilnd_wakeup_rca_thread(void)
 804 {
 805 }
 806
 807 int
 808 kgnilnd_get_node_state(__u32 nid)
 809 {
 810         return GNILND_RCA_NODE_UP;
 811 }
 812 #endif /* GNILND_USE_RCA */