lustre/ptlrpc/pinger.c

   1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
   2  * vim:expandtab:shiftwidth=8:tabstop=8:
   3  *
   4  * Portal-RPC reconnection and replay operations, for use in recovery.
   5  *
   6  *  Copyright (c) 2003 Cluster File Systems, Inc.
   7  *   Authors: Phil Schwan <phil@clusterfs.com>
   8  *            Mike Shaver <shaver@clusterfs.com>
   9  *
  10  *   This file is part of the Lustre file system, http://www.lustre.org
  11  *   Lustre is a trademark of Cluster File Systems, Inc.
  12  *
  13  *   You may have signed or agreed to another license before downloading
  14  *   this software.  If so, you are bound by the terms and conditions
  15  *   of that agreement, and the following does not apply to you.  See the
  16  *   LICENSE file included with this distribution for more information.
  17  *
  18  *   If you did not agree to a different license, then this copy of Lustre
  19  *   is open source software; you can redistribute it and/or modify it
  20  *   under the terms of version 2 of the GNU General Public License as
  21  *   published by the Free Software Foundation.
  22  *
  23  *   In either case, Lustre is distributed in the hope that it will be
  24  *   useful, but WITHOUT ANY WARRANTY; without even the implied warranty
  25  *   of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  26  *   license text for more details.
  27  */
  28
  29 #ifndef __KERNEL__
  30 #include <liblustre.h>
  31 #else
  32 #define DEBUG_SUBSYSTEM S_RPC
  33 #endif
  34
  35 #include <obd_support.h>
  36 #include <obd_class.h>
  37 #include "ptlrpc_internal.h"
  38
  39 struct semaphore pinger_sem;
  40 static CFS_LIST_HEAD(pinger_imports);
  41
  42 int ptlrpc_ping(struct obd_import *imp)
  43 {
  44         struct ptlrpc_request *req;
  45         ENTRY;
  46
  47         req = ptlrpc_request_alloc_pack(imp, &RQF_OBD_PING, LUSTRE_OBD_VERSION,
  48                                         OBD_PING);
  49         if (req == NULL) {
  50                 CERROR("OOM trying to ping %s->%s\n",
  51                        imp->imp_obd->obd_uuid.uuid,
  52                        obd2cli_tgt(imp->imp_obd));
  53                 RETURN(-ENOMEM);
  54         }
  55
  56         DEBUG_REQ(D_INFO, req, "pinging %s->%s",
  57                   imp->imp_obd->obd_uuid.uuid, obd2cli_tgt(imp->imp_obd));
  58         req->rq_no_resend = req->rq_no_delay = 1;
  59         ptlrpc_request_set_replen(req);
  60         ptlrpcd_add_req(req);
  61
  62         RETURN(0);
  63 }
  64
  65 void ptlrpc_update_next_ping(struct obd_import *imp)
  66 {
  67 #ifdef ENABLE_PINGER
  68         int time = PING_INTERVAL;
  69         if (imp->imp_state == LUSTRE_IMP_DISCON) {
  70                 int dtime = max_t(int, CONNECTION_SWITCH_MIN,
  71                                   AT_OFF ? 0 :
  72                                   at_get(&imp->imp_at.iat_net_latency));
  73                 time = min(time, dtime);
  74         }
  75         imp->imp_next_ping = cfs_time_shift(time);
  76 #endif /* ENABLE_PINGER */
  77 }
  78
  79 void ptlrpc_ping_import_soon(struct obd_import *imp)
  80 {
  81         imp->imp_next_ping = cfs_time_current();
  82 }
  83
  84 static inline int ptlrpc_next_reconnect(struct obd_import *imp)
  85 {
  86         if (imp->imp_server_timeout)
  87                 return cfs_time_shift(obd_timeout / 2);
  88         else
  89                 return cfs_time_shift(obd_timeout);
  90 }
  91
  92 static atomic_t suspend_timeouts = ATOMIC_INIT(0);
  93 static cfs_time_t suspend_wakeup_time = 0;
  94
  95 #ifdef __KERNEL__
  96 static wait_queue_head_t suspend_timeouts_waitq;
  97 #endif
  98
  99 cfs_time_t ptlrpc_suspend_wakeup_time(void)
 100 {
 101         return suspend_wakeup_time;
 102 }
 103
 104 void ptlrpc_deactivate_timeouts(struct obd_import *imp)
 105 {
 106         /*XXX: disabled for now, will be replaced by adaptive timeouts */
 107 #if 0
 108         if (imp->imp_no_timeout)
 109                 return;
 110         imp->imp_no_timeout = 1;
 111         atomic_inc(&suspend_timeouts);
 112         CDEBUG(D_HA|D_WARNING, "deactivate timeouts %u\n", atomic_read(&suspend_timeouts));
 113 #endif
 114 }
 115
 116 void ptlrpc_activate_timeouts(struct obd_import *imp)
 117 {
 118         /*XXX: disabled for now, will be replaced by adaptive timeouts */
 119 #if 0
 120         if (!imp->imp_no_timeout)
 121                 return;
 122         imp->imp_no_timeout = 0;
 123         LASSERT(atomic_read(&suspend_timeouts) > 0);
 124         if (atomic_dec_and_test(&suspend_timeouts)) {
 125                 suspend_wakeup_time = cfs_time_current();
 126                 wake_up(&suspend_timeouts_waitq);
 127         }
 128         CDEBUG(D_HA|D_WARNING, "activate timeouts %u\n", atomic_read(&suspend_timeouts));
 129 #endif
 130 }
 131
 132 int ptlrpc_check_suspend(void)
 133 {
 134         if (atomic_read(&suspend_timeouts))
 135                 return 1;
 136         return 0;
 137 }
 138
 139 int ptlrpc_check_and_wait_suspend(struct ptlrpc_request *req)
 140 {
 141         struct l_wait_info lwi;
 142
 143         if (atomic_read(&suspend_timeouts)) {
 144                 DEBUG_REQ(D_NET, req, "-- suspend %d regular timeout",
 145                           atomic_read(&suspend_timeouts));
 146                 lwi = LWI_INTR(NULL, NULL);
 147                 l_wait_event(suspend_timeouts_waitq,
 148                              atomic_read(&suspend_timeouts) == 0, &lwi);
 149                 DEBUG_REQ(D_NET, req, "-- recharge regular timeout");
 150                 return 1;
 151         }
 152         return 0;
 153 }
 154
 155 #ifdef __KERNEL__
 156
 157 static void ptlrpc_pinger_process_import(struct obd_import *imp,
 158                                          unsigned long this_ping)
 159 {
 160         int force, level;
 161
 162         spin_lock(&imp->imp_lock);
 163         level = imp->imp_state;
 164         force = imp->imp_force_verify;
 165         if (force)
 166                 imp->imp_force_verify = 0;
 167         spin_unlock(&imp->imp_lock);
 168
 169         CDEBUG(level == LUSTRE_IMP_FULL ? D_INFO : D_HA,
 170                "level %s/%u force %u deactive %u pingable %u\n",
 171                ptlrpc_import_state_name(level), level,
 172                force, imp->imp_deactive, imp->imp_pingable);
 173
 174         if (cfs_time_aftereq(imp->imp_next_ping - 5 * CFS_TICK,
 175                              this_ping) && force == 0)
 176                 return;
 177
 178         if (level == LUSTRE_IMP_DISCON && !imp->imp_deactive) {
 179                 /* wait at least a timeout before trying recovery again */
 180                 imp->imp_next_ping = ptlrpc_next_reconnect(imp);
 181                 ptlrpc_initiate_recovery(imp);
 182         } else if (level != LUSTRE_IMP_FULL ||
 183                    imp->imp_obd->obd_no_recov ||
 184                    imp->imp_deactive) {
 185                 CDEBUG(D_HA, "not pinging %s (in recovery "
 186                        " or recovery disabled: %s)\n",
 187                        obd2cli_tgt(imp->imp_obd),
 188                        ptlrpc_import_state_name(level));
 189         } else if (imp->imp_pingable || force) {
 190                 ptlrpc_ping(imp);
 191         }
 192 }
 193
 194 static int ptlrpc_pinger_main(void *arg)
 195 {
 196         struct ptlrpc_svc_data *data = (struct ptlrpc_svc_data *)arg;
 197         struct ptlrpc_thread *thread = data->thread;
 198         ENTRY;
 199
 200         cfs_daemonize(data->name);
 201
 202         /* Record that the thread is running */
 203         thread->t_flags = SVC_RUNNING;
 204         cfs_waitq_signal(&thread->t_ctl_waitq);
 205
 206         /* And now, loop forever, pinging as needed. */
 207         while (1) {
 208                 cfs_time_t this_ping = cfs_time_current();
 209                 struct l_wait_info lwi;
 210                 cfs_duration_t time_to_next_ping;
 211                 struct list_head *iter;
 212
 213                 mutex_down(&pinger_sem);
 214                 list_for_each(iter, &pinger_imports) {
 215                         struct obd_import *imp =
 216                                 list_entry(iter, struct obd_import,
 217                                            imp_pinger_chain);
 218
 219                         ptlrpc_pinger_process_import(imp, this_ping);
 220                         /* obd_timeout might have changed */
 221                         if (imp->imp_pingable && imp->imp_next_ping &&
 222                             cfs_time_after(imp->imp_next_ping,
 223                                            cfs_time_add(this_ping,
 224                                                         cfs_time_seconds(PING_INTERVAL))))
 225                                 ptlrpc_update_next_ping(imp);
 226                 }
 227                 mutex_up(&pinger_sem);
 228                 /* update memory usage info */
 229                 obd_update_maxusage();
 230
 231                 /* Wait until the next ping time, or until we're stopped. */
 232                 time_to_next_ping = cfs_time_sub(cfs_time_add(this_ping,
 233                                                cfs_time_seconds(PING_INTERVAL)),
 234                                                cfs_time_current());
 235
 236                 /* The ping sent by ptlrpc_send_rpc may get sent out
 237                    say .01 second after this.
 238                    ptlrpc_pinger_sending_on_import will then set the
 239                    next ping time to next_ping + .01 sec, which means
 240                    we will SKIP the next ping at next_ping, and the
 241                    ping will get sent 2 timeouts from now!  Beware. */
 242                 CDEBUG(D_INFO, "next ping in "CFS_DURATION_T" ("CFS_TIME_T")\n",
 243                                time_to_next_ping,
 244                                cfs_time_add(this_ping,
 245                                             cfs_time_seconds(PING_INTERVAL)));
 246                 if (time_to_next_ping > 0) {
 247                         lwi = LWI_TIMEOUT(max_t(cfs_duration_t,
 248                                                 time_to_next_ping,
 249                                                 cfs_time_seconds(1)),
 250                                           NULL, NULL);
 251                         l_wait_event(thread->t_ctl_waitq,
 252                                      thread->t_flags & (SVC_STOPPING|SVC_EVENT),
 253                                      &lwi);
 254                         if (thread->t_flags & SVC_STOPPING) {
 255                                 thread->t_flags &= ~SVC_STOPPING;
 256                                 EXIT;
 257                                 break;
 258                         } else if (thread->t_flags & SVC_EVENT) {
 259                                 /* woken after adding import to reset timer */
 260                                 thread->t_flags &= ~SVC_EVENT;
 261                         }
 262                 }
 263         }
 264
 265         thread->t_flags = SVC_STOPPED;
 266         cfs_waitq_signal(&thread->t_ctl_waitq);
 267
 268         CDEBUG(D_NET, "pinger thread exiting, process %d\n", cfs_curproc_pid());
 269         return 0;
 270 }
 271
 272 static struct ptlrpc_thread *pinger_thread = NULL;
 273
 274 int ptlrpc_start_pinger(void)
 275 {
 276         struct l_wait_info lwi = { 0 };
 277         struct ptlrpc_svc_data d;
 278         int rc;
 279 #ifndef ENABLE_PINGER
 280         return 0;
 281 #endif
 282         ENTRY;
 283
 284         if (pinger_thread != NULL)
 285                 RETURN(-EALREADY);
 286
 287         OBD_ALLOC_PTR(pinger_thread);
 288         if (pinger_thread == NULL)
 289                 RETURN(-ENOMEM);
 290         cfs_waitq_init(&pinger_thread->t_ctl_waitq);
 291         cfs_waitq_init(&suspend_timeouts_waitq);
 292
 293         d.name = "ll_ping";
 294         d.thread = pinger_thread;
 295
 296         /* CLONE_VM and CLONE_FILES just avoid a needless copy, because we
 297          * just drop the VM and FILES in ptlrpc_daemonize() right away. */
 298         rc = cfs_kernel_thread(ptlrpc_pinger_main, &d, CLONE_VM | CLONE_FILES);
 299         if (rc < 0) {
 300                 CERROR("cannot start thread: %d\n", rc);
 301                 OBD_FREE(pinger_thread, sizeof(*pinger_thread));
 302                 pinger_thread = NULL;
 303                 RETURN(rc);
 304         }
 305         l_wait_event(pinger_thread->t_ctl_waitq,
 306                      pinger_thread->t_flags & SVC_RUNNING, &lwi);
 307
 308         RETURN(0);
 309 }
 310
 311 int ptlrpc_stop_pinger(void)
 312 {
 313         struct l_wait_info lwi = { 0 };
 314         int rc = 0;
 315 #ifndef ENABLE_PINGER
 316         return 0;
 317 #endif
 318         ENTRY;
 319
 320         if (pinger_thread == NULL)
 321                 RETURN(-EALREADY);
 322         mutex_down(&pinger_sem);
 323         pinger_thread->t_flags = SVC_STOPPING;
 324         cfs_waitq_signal(&pinger_thread->t_ctl_waitq);
 325         mutex_up(&pinger_sem);
 326
 327         l_wait_event(pinger_thread->t_ctl_waitq,
 328                      (pinger_thread->t_flags & SVC_STOPPED), &lwi);
 329
 330         OBD_FREE_PTR(pinger_thread);
 331         pinger_thread = NULL;
 332         RETURN(rc);
 333 }
 334
 335 void ptlrpc_pinger_sending_on_import(struct obd_import *imp)
 336 {
 337         ptlrpc_update_next_ping(imp);
 338 }
 339
 340 int ptlrpc_pinger_add_import(struct obd_import *imp)
 341 {
 342         ENTRY;
 343         if (!list_empty(&imp->imp_pinger_chain))
 344                 RETURN(-EALREADY);
 345
 346         mutex_down(&pinger_sem);
 347         CDEBUG(D_HA, "adding pingable import %s->%s\n",
 348                imp->imp_obd->obd_uuid.uuid, obd2cli_tgt(imp->imp_obd));
 349         /* if we add to pinger we want recovery on this import */
 350         imp->imp_obd->obd_no_recov = 0;
 351         ptlrpc_update_next_ping(imp);
 352         /* XXX sort, blah blah */
 353         list_add_tail(&imp->imp_pinger_chain, &pinger_imports);
 354         class_import_get(imp);
 355
 356         ptlrpc_pinger_wake_up();
 357         mutex_up(&pinger_sem);
 358
 359         RETURN(0);
 360 }
 361
 362 int ptlrpc_pinger_del_import(struct obd_import *imp)
 363 {
 364         ENTRY;
 365         if (list_empty(&imp->imp_pinger_chain))
 366                 RETURN(-ENOENT);
 367
 368         mutex_down(&pinger_sem);
 369         list_del_init(&imp->imp_pinger_chain);
 370         CDEBUG(D_HA, "removing pingable import %s->%s\n",
 371                imp->imp_obd->obd_uuid.uuid, obd2cli_tgt(imp->imp_obd));
 372         /* if we remove from pinger we don't want recovery on this import */
 373         imp->imp_obd->obd_no_recov = 1;
 374         class_import_put(imp);
 375         mutex_up(&pinger_sem);
 376         RETURN(0);
 377 }
 378
 379 void ptlrpc_pinger_wake_up()
 380 {
 381 #ifdef ENABLE_PINGER
 382         pinger_thread->t_flags |= SVC_EVENT;
 383         cfs_waitq_signal(&pinger_thread->t_ctl_waitq);
 384 #endif
 385 }
 386
 387 /* Ping evictor thread */
 388 #define PET_READY     1
 389 #define PET_TERMINATE 2
 390
 391 static int               pet_refcount = 0;
 392 static int               pet_state;
 393 static wait_queue_head_t pet_waitq;
 394 static struct obd_export *pet_exp = NULL;
 395 static spinlock_t        pet_lock = SPIN_LOCK_UNLOCKED;
 396
 397 int ping_evictor_wake(struct obd_export *exp)
 398 {
 399         spin_lock(&pet_lock);
 400         if (pet_exp || (pet_state != PET_READY)) {
 401                 /* eventually the new obd will call here again. */
 402                 spin_unlock(&pet_lock);
 403                 return 1;
 404         }
 405
 406         /* We have to make sure the obd isn't destroyed between now and when
 407          * the ping evictor runs.  We'll take a reference here, and drop it
 408          * when we finish in the evictor.  We don't really care about this
 409          * export in particular; we just need one to keep the obd alive. */
 410         pet_exp = class_export_get(exp);
 411         spin_unlock(&pet_lock);
 412
 413         wake_up(&pet_waitq);
 414         return 0;
 415 }
 416
 417 static int ping_evictor_main(void *arg)
 418 {
 419         struct obd_device *obd;
 420         struct obd_export *exp;
 421         struct l_wait_info lwi = { 0 };
 422         time_t expire_time;
 423         ENTRY;
 424
 425         ptlrpc_daemonize("ll_evictor");
 426
 427         CDEBUG(D_HA, "Starting Ping Evictor\n");
 428         pet_exp = NULL;
 429         pet_state = PET_READY;
 430         while (1) {
 431                 l_wait_event(pet_waitq, pet_exp ||
 432                              (pet_state == PET_TERMINATE), &lwi);
 433                 if (pet_state == PET_TERMINATE)
 434                         break;
 435
 436                 /* we only get here if pet_exp != NULL, and the end of this
 437                  * loop is the only place which sets it NULL again, so lock
 438                  * is not strictly necessary. */
 439                 spin_lock(&pet_lock);
 440                 obd = pet_exp->exp_obd;
 441                 spin_unlock(&pet_lock);
 442
 443                 expire_time = cfs_time_current_sec() - PING_EVICT_TIMEOUT;
 444
 445                 CDEBUG(D_HA, "evicting all exports of obd %s older than %ld\n",
 446                        obd->obd_name, expire_time);
 447
 448                 /* Exports can't be deleted out of the list while we hold
 449                  * the obd lock (class_unlink_export), which means we can't
 450                  * lose the last ref on the export.  If they've already been
 451                  * removed from the list, we won't find them here. */
 452                 spin_lock(&obd->obd_dev_lock);
 453                 while (!list_empty(&obd->obd_exports_timed)) {
 454                         exp = list_entry(obd->obd_exports_timed.next,
 455                                          struct obd_export,exp_obd_chain_timed);
 456                         if (expire_time > exp->exp_last_request_time) {
 457                                 class_export_get(exp);
 458                                 spin_unlock(&obd->obd_dev_lock);
 459                                  LCONSOLE_WARN("%s: haven't heard from client %s"
 460                                               " (at %s) in %ld seconds. I think"
 461                                               " it's dead, and I am evicting"
 462                                               " it. exp %p, cur %ld expire %ld"
 463                                               " last %ld\n",
 464                                               obd->obd_name,
 465                                               obd_uuid2str(&exp->exp_client_uuid),
 466                                               obd_export_nid2str(exp),
 467                                               (long)(cfs_time_current_sec() -
 468                                                      exp->exp_last_request_time),
 469                                               exp, (long)cfs_time_current_sec(),
 470                                               (long)expire_time,
 471                                               (long)exp->exp_last_request_time);
 472                                 CDEBUG(D_HA, "Last request was at %ld\n",
 473                                        exp->exp_last_request_time);
 474                                 class_fail_export(exp);
 475                                 class_export_put(exp);
 476                                 spin_lock(&obd->obd_dev_lock);
 477                         } else {
 478                                 /* List is sorted, so everyone below is ok */
 479                                 break;
 480                         }
 481                 }
 482                 spin_unlock(&obd->obd_dev_lock);
 483
 484                 class_export_put(pet_exp);
 485
 486                 spin_lock(&pet_lock);
 487                 pet_exp = NULL;
 488                 spin_unlock(&pet_lock);
 489         }
 490         CDEBUG(D_HA, "Exiting Ping Evictor\n");
 491
 492         RETURN(0);
 493 }
 494
 495 void ping_evictor_start(void)
 496 {
 497         int rc;
 498
 499         if (++pet_refcount > 1)
 500                 return;
 501
 502         init_waitqueue_head(&pet_waitq);
 503
 504         rc = cfs_kernel_thread(ping_evictor_main, NULL, CLONE_VM | CLONE_FILES);
 505         if (rc < 0) {
 506                 pet_refcount--;
 507                 CERROR("Cannot start ping evictor thread: %d\n", rc);
 508         }
 509 }
 510 EXPORT_SYMBOL(ping_evictor_start);
 511
 512 void ping_evictor_stop(void)
 513 {
 514         if (--pet_refcount > 0)
 515                 return;
 516
 517         pet_state = PET_TERMINATE;
 518         wake_up(&pet_waitq);
 519 }
 520 EXPORT_SYMBOL(ping_evictor_stop);
 521 #else /* !__KERNEL__ */
 522
 523 /* XXX
 524  * the current implementation of pinger in liblustre is not optimized
 525  */
 526
 527 #ifdef ENABLE_PINGER
 528 static struct pinger_data {
 529         int             pd_recursion;
 530         cfs_time_t      pd_this_ping;   /* jiffies */
 531         cfs_time_t      pd_next_ping;   /* jiffies */
 532         struct ptlrpc_request_set *pd_set;
 533 } pinger_args;
 534
 535 static int pinger_check_rpcs(void *arg)
 536 {
 537         cfs_time_t curtime = cfs_time_current();
 538         struct ptlrpc_request *req;
 539         struct ptlrpc_request_set *set;
 540         struct list_head *iter;
 541         struct pinger_data *pd = &pinger_args;
 542         int rc;
 543
 544         /* prevent recursion */
 545         if (pd->pd_recursion++) {
 546                 CDEBUG(D_HA, "pinger: recursion! quit\n");
 547                 LASSERT(pd->pd_set);
 548                 pd->pd_recursion--;
 549                 return 0;
 550         }
 551
 552         /* have we reached ping point? */
 553         if (!pd->pd_set && time_before(curtime, pd->pd_next_ping)) {
 554                 pd->pd_recursion--;
 555                 return 0;
 556         }
 557
 558         /* if we have rpc_set already, continue processing it */
 559         if (pd->pd_set) {
 560                 LASSERT(pd->pd_this_ping);
 561                 set = pd->pd_set;
 562                 goto do_check_set;
 563         }
 564
 565         pd->pd_this_ping = curtime;
 566         pd->pd_set = ptlrpc_prep_set();
 567         if (pd->pd_set == NULL)
 568                 goto out;
 569         set = pd->pd_set;
 570
 571         /* add rpcs into set */
 572         mutex_down(&pinger_sem);
 573         list_for_each(iter, &pinger_imports) {
 574                 struct obd_import *imp =
 575                         list_entry(iter, struct obd_import, imp_pinger_chain);
 576                 int generation, level;
 577
 578                 if (cfs_time_aftereq(pd->pd_this_ping,
 579                                      imp->imp_next_ping - 5 * CFS_TICK)) {
 580                         /* Add a ping. */
 581                         spin_lock(&imp->imp_lock);
 582                         generation = imp->imp_generation;
 583                         level = imp->imp_state;
 584                         spin_unlock(&imp->imp_lock);
 585
 586                         if (level != LUSTRE_IMP_FULL) {
 587                                 CDEBUG(D_HA,
 588                                        "not pinging %s (in recovery)\n",
 589                                        obd2cli_tgt(imp->imp_obd));
 590                                 continue;
 591                         }
 592
 593                         req = ptlrpc_request_alloc_pack(imp, &RQF_OBD_PING,
 594                                                         LUSTRE_OBD_VERSION,
 595                                                         OBD_PING);
 596                         if (req == NULL) {
 597                                 CERROR("OOM trying to ping %s->%s\n",
 598                                        imp->imp_obd->obd_uuid.uuid,
 599                                        obd2cli_tgt(imp->imp_obd));
 600                                 break;
 601                         }
 602
 603                         req->rq_no_resend = 1;
 604                         ptlrpc_request_set_replen(req);
 605                         req->rq_send_state = LUSTRE_IMP_FULL;
 606                         req->rq_phase = RQ_PHASE_RPC;
 607                         req->rq_import_generation = generation;
 608                         ptlrpc_set_add_req(set, req);
 609                 } else {
 610                         CDEBUG(D_INFO, "don't need to ping %s ("CFS_TIME_T
 611                                " > "CFS_TIME_T")\n", obd2cli_tgt(imp->imp_obd),
 612                                imp->imp_next_ping, pd->pd_this_ping);
 613                 }
 614         }
 615         pd->pd_this_ping = curtime;
 616         mutex_up(&pinger_sem);
 617
 618         /* Might be empty, that's OK. */
 619         if (set->set_remaining == 0)
 620                 CDEBUG(D_RPCTRACE, "nothing to ping\n");
 621
 622         list_for_each(iter, &set->set_requests) {
 623                 struct ptlrpc_request *req =
 624                         list_entry(iter, struct ptlrpc_request,
 625                                    rq_set_chain);
 626                 DEBUG_REQ(D_RPCTRACE, req, "pinging %s->%s",
 627                           req->rq_import->imp_obd->obd_uuid.uuid,
 628                           obd2cli_tgt(req->rq_import->imp_obd));
 629                 (void)ptl_send_rpc(req, 0);
 630         }
 631
 632 do_check_set:
 633         rc = ptlrpc_check_set(set);
 634
 635         /* not finished, and we are not expired, simply return */
 636         if (!rc && cfs_time_before(curtime, cfs_time_add(pd->pd_this_ping,
 637                                             cfs_time_seconds(PING_INTERVAL)))) {
 638                 CDEBUG(D_RPCTRACE, "not finished, but also not expired\n");
 639                 pd->pd_recursion--;
 640                 return 0;
 641         }
 642
 643         /* Expire all the requests that didn't come back. */
 644         mutex_down(&pinger_sem);
 645         list_for_each(iter, &set->set_requests) {
 646                 req = list_entry(iter, struct ptlrpc_request,
 647                                  rq_set_chain);
 648
 649                 if (req->rq_phase == RQ_PHASE_COMPLETE)
 650                         continue;
 651
 652                 req->rq_phase = RQ_PHASE_COMPLETE;
 653                 atomic_dec(&req->rq_import->imp_inflight);
 654                 set->set_remaining--;
 655                 /* If it was disconnected, don't sweat it. */
 656                 if (list_empty(&req->rq_import->imp_pinger_chain)) {
 657                         ptlrpc_unregister_reply(req);
 658                         continue;
 659                 }
 660
 661                 CDEBUG(D_RPCTRACE, "pinger initiate expire_one_request\n");
 662                 ptlrpc_expire_one_request(req);
 663         }
 664         mutex_up(&pinger_sem);
 665
 666         ptlrpc_set_destroy(set);
 667         pd->pd_set = NULL;
 668
 669 out:
 670         pd->pd_next_ping = cfs_time_add(pd->pd_this_ping,
 671                                         cfs_time_seconds(PING_INTERVAL));
 672         pd->pd_this_ping = 0; /* XXX for debug */
 673
 674         CDEBUG(D_INFO, "finished a round ping\n");
 675         pd->pd_recursion--;
 676         return 0;
 677 }
 678
 679 static void *pinger_callback = NULL;
 680 #endif /* ENABLE_PINGER */
 681
 682 int ptlrpc_start_pinger(void)
 683 {
 684 #ifdef ENABLE_PINGER
 685         memset(&pinger_args, 0, sizeof(pinger_args));
 686         pinger_callback = liblustre_register_wait_callback("pinger_check_rpcs",
 687                                                            &pinger_check_rpcs,
 688                                                            &pinger_args);
 689 #endif
 690         return 0;
 691 }
 692
 693 int ptlrpc_stop_pinger(void)
 694 {
 695 #ifdef ENABLE_PINGER
 696         if (pinger_callback)
 697                 liblustre_deregister_wait_callback(pinger_callback);
 698 #endif
 699         return 0;
 700 }
 701
 702 void ptlrpc_pinger_sending_on_import(struct obd_import *imp)
 703 {
 704 #ifdef ENABLE_PINGER
 705         mutex_down(&pinger_sem);
 706         ptlrpc_update_next_ping(imp);
 707         if (pinger_args.pd_set == NULL &&
 708             time_before(imp->imp_next_ping, pinger_args.pd_next_ping)) {
 709                 CDEBUG(D_HA, "set next ping to "CFS_TIME_T"(cur "CFS_TIME_T")\n",
 710                         imp->imp_next_ping, cfs_time_current());
 711                 pinger_args.pd_next_ping = imp->imp_next_ping;
 712         }
 713         mutex_up(&pinger_sem);
 714 #endif
 715 }
 716
 717 int ptlrpc_pinger_add_import(struct obd_import *imp)
 718 {
 719         ENTRY;
 720         if (!list_empty(&imp->imp_pinger_chain))
 721                 RETURN(-EALREADY);
 722
 723         CDEBUG(D_HA, "adding pingable import %s->%s\n",
 724                imp->imp_obd->obd_uuid.uuid, obd2cli_tgt(imp->imp_obd));
 725         ptlrpc_pinger_sending_on_import(imp);
 726
 727         mutex_down(&pinger_sem);
 728         list_add_tail(&imp->imp_pinger_chain, &pinger_imports);
 729         class_import_get(imp);
 730         mutex_up(&pinger_sem);
 731
 732         RETURN(0);
 733 }
 734
 735 int ptlrpc_pinger_del_import(struct obd_import *imp)
 736 {
 737         ENTRY;
 738         if (list_empty(&imp->imp_pinger_chain))
 739                 RETURN(-ENOENT);
 740
 741         mutex_down(&pinger_sem);
 742         list_del_init(&imp->imp_pinger_chain);
 743         CDEBUG(D_HA, "removing pingable import %s->%s\n",
 744                imp->imp_obd->obd_uuid.uuid, obd2cli_tgt(imp->imp_obd));
 745         class_import_put(imp);
 746         mutex_up(&pinger_sem);
 747         RETURN(0);
 748 }
 749
 750 void ptlrpc_pinger_wake_up()
 751 {
 752 #ifdef ENABLE_PINGER
 753         /* XXX force pinger to run, if needed */
 754         struct obd_import *imp;
 755         ENTRY;
 756         list_for_each_entry(imp, &pinger_imports, imp_pinger_chain) {
 757                 CDEBUG(D_RPCTRACE, "checking import %s->%s\n",
 758                        imp->imp_obd->obd_uuid.uuid, obd2cli_tgt(imp->imp_obd));
 759 #ifdef ENABLE_LIBLUSTRE_RECOVERY
 760                 if (imp->imp_state == LUSTRE_IMP_DISCON && !imp->imp_deactive)
 761 #else
 762                 /*XXX only recover for the initial connection */
 763                 if (!lustre_handle_is_used(&imp->imp_remote_handle) &&
 764                     imp->imp_state == LUSTRE_IMP_DISCON && !imp->imp_deactive)
 765 #endif
 766                         ptlrpc_initiate_recovery(imp);
 767                 else if (imp->imp_state != LUSTRE_IMP_FULL)
 768                         CDEBUG(D_HA, "Refused to recover import %s->%s "
 769                                      "state %d, deactive %d\n",
 770                                      imp->imp_obd->obd_uuid.uuid,
 771                                      obd2cli_tgt(imp->imp_obd), imp->imp_state,
 772                                      imp->imp_deactive);
 773         }
 774         EXIT;
 775 #endif
 776 }
 777 #endif /* !__KERNEL__ */