lustre/ptlrpc/pinger.c

   1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
   2  * vim:expandtab:shiftwidth=8:tabstop=8:
   3  *
   4  * GPL HEADER START
   5  *
   6  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 only,
  10  * as published by the Free Software Foundation.
  11  *
  12  * This program is distributed in the hope that it will be useful, but
  13  * WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * General Public License version 2 for more details (a copy is included
  16  * in the LICENSE file that accompanied this code).
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * version 2 along with this program; If not, see
  20  * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
  21  *
  22  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  23  * CA 95054 USA or visit www.sun.com if you need additional information or
  24  * have any questions.
  25  *
  26  * GPL HEADER END
  27  */
  28 /*
  29  * Copyright  2008 Sun Microsystems, Inc. All rights reserved
  30  * Use is subject to license terms.
  31  */
  32 /*
  33  * This file is part of Lustre, http://www.lustre.org/
  34  * Lustre is a trademark of Sun Microsystems, Inc.
  35  *
  36  * lustre/ptlrpc/pinger.c
  37  *
  38  * Portal-RPC reconnection and replay operations, for use in recovery.
  39  */
  40
  41 #ifndef __KERNEL__
  42 #include <liblustre.h>
  43 #else
  44 #define DEBUG_SUBSYSTEM S_RPC
  45 #endif
  46
  47 #include <obd_support.h>
  48 #include <obd_class.h>
  49 #include <lustre_net.h>
  50 #include "ptlrpc_internal.h"
  51
  52 struct semaphore pinger_sem;
  53 static struct list_head pinger_imports = CFS_LIST_HEAD_INIT(pinger_imports);
  54 static struct list_head timeout_list = CFS_LIST_HEAD_INIT(timeout_list);
  55
  56 struct ptlrpc_request *
  57 ptlrpc_prep_ping(struct obd_import *imp)
  58 {
  59         struct ptlrpc_request *req;
  60
  61         req = ptlrpc_prep_req(imp, LUSTRE_OBD_VERSION,
  62                               OBD_PING, 1, NULL, NULL);
  63         if (req) {
  64                 ptlrpc_req_set_repsize(req, 1, NULL);
  65                 req->rq_no_resend = req->rq_no_delay = 1;
  66         }
  67         return req;
  68 }
  69
  70 int ptlrpc_obd_ping(struct obd_device *obd)
  71 {
  72         int rc;
  73         struct ptlrpc_request *req;
  74         ENTRY;
  75
  76         req = ptlrpc_prep_ping(obd->u.cli.cl_import);
  77         if (req == NULL)
  78                 RETURN(-ENOMEM);
  79
  80         req->rq_send_state = LUSTRE_IMP_FULL;
  81
  82         rc = ptlrpc_queue_wait(req);
  83
  84         ptlrpc_req_finished(req);
  85
  86         RETURN(rc);
  87 }
  88 EXPORT_SYMBOL(ptlrpc_obd_ping);
  89
  90 int ptlrpc_ping(struct obd_import *imp)
  91 {
  92         struct ptlrpc_request *req;
  93         int rc = 0;
  94         ENTRY;
  95
  96         req = ptlrpc_prep_ping(imp);
  97         if (req) {
  98                 DEBUG_REQ(D_INFO, req, "pinging %s->%s",
  99                           imp->imp_obd->obd_uuid.uuid,
 100                           obd2cli_tgt(imp->imp_obd));
 101
 102                 /* To quickly detect server failure ping timeouts must be
 103                  * kept small.  Therefore we must override/ignore the server
 104                  * rpc completion estimate which may be very large since
 105                  * it includes non-ping service times.  The right long term
 106                  * fix will be to add a per-server (not per-service) thread
 107                  * in order to reduce the number of pings in the system in
 108                  * general (see bug 12471). */
 109                 if (!AT_OFF) {
 110                         req->rq_timeout = PING_SVC_TIMEOUT +
 111                                           at_get(&imp->imp_at.iat_net_latency);
 112                         lustre_msg_set_timeout(req->rq_reqmsg, req->rq_timeout);
 113                 }
 114
 115                 ptlrpcd_add_req(req);
 116         } else {
 117                 CERROR("OOM trying to ping %s->%s\n",
 118                        imp->imp_obd->obd_uuid.uuid,
 119                        obd2cli_tgt(imp->imp_obd));
 120                 rc = -ENOMEM;
 121         }
 122
 123         RETURN(rc);
 124 }
 125 EXPORT_SYMBOL(ptlrpc_ping);
 126
 127 static void ptlrpc_update_next_ping(struct obd_import *imp, int soon)
 128 {
 129 #ifdef ENABLE_PINGER
 130         cfs_time_t delay, dtime, ctime = cfs_time_current();
 131
 132         if (imp->imp_state == LUSTRE_IMP_DISCON ||
 133             imp->imp_state == LUSTRE_IMP_CONNECTING) {
 134                 /* In the disconnected case aggressively reconnect, for
 135                  * this request the AT service timeout will be set to
 136                  * INITIAL_CONNECT_TIMEOUT.  To ensure the request times
 137                  * out before we send another we add one extra second. */
 138                 dtime = cfs_time_seconds(max_t(int, CONNECTION_SWITCH_MIN,
 139                                 AT_OFF ? 0 : INITIAL_CONNECT_TIMEOUT + 1 +
 140                                 at_get(&imp->imp_at.iat_net_latency)));
 141         } else {
 142                 /* In the common case we want to cluster the pings at
 143                  * at regular intervals to minimize system noise. */
 144                 delay = cfs_time_seconds(soon ? PING_INTERVAL_SHORT :
 145                                          PING_INTERVAL);
 146                 dtime = delay - (ctime % delay);
 147         }
 148         /* May harmlessly race with ptlrpc_update_next_ping() */
 149         imp->imp_next_ping = cfs_time_add(ctime, dtime);
 150
 151         CDEBUG(D_INFO, "Setting %s next ping to "CFS_TIME_T" ("CFS_TIME_T")\n",
 152                obd2cli_tgt(imp->imp_obd), imp->imp_next_ping, dtime);
 153
 154 #endif /* ENABLE_PINGER */
 155 }
 156
 157 void ptlrpc_ping_import_soon(struct obd_import *imp)
 158 {
 159         imp->imp_next_ping = cfs_time_current();
 160 }
 161
 162 static inline int imp_is_deactive(struct obd_import *imp)
 163 {
 164         return (imp->imp_deactive ||
 165                 OBD_FAIL_CHECK(OBD_FAIL_PTLRPC_IMP_DEACTIVE));
 166 }
 167
 168 cfs_duration_t pinger_check_timeout(cfs_time_t time)
 169 {
 170         struct timeout_item *item;
 171         cfs_time_t timeout = PING_INTERVAL;
 172
 173         /* The timeout list is a increase order sorted list */
 174         mutex_down(&pinger_sem);
 175         list_for_each_entry(item, &timeout_list, ti_chain) {
 176                 int ti_timeout = item->ti_timeout;
 177                 if (timeout > ti_timeout)
 178                          timeout = ti_timeout;
 179                 break;
 180         }
 181         mutex_up(&pinger_sem);
 182
 183         return cfs_time_sub(cfs_time_add(time, cfs_time_seconds(timeout)),
 184                                          cfs_time_current());
 185 }
 186
 187 #ifdef __KERNEL__
 188 static int ptlrpc_pinger_main(void *arg)
 189 {
 190         struct ptlrpc_svc_data *data = (struct ptlrpc_svc_data *)arg;
 191         struct ptlrpc_thread *thread = data->thread;
 192         ENTRY;
 193
 194         cfs_daemonize(data->name);
 195
 196         /* Record that the thread is running */
 197         thread->t_flags = SVC_RUNNING;
 198         cfs_waitq_signal(&thread->t_ctl_waitq);
 199
 200         /* And now, loop forever, pinging as needed. */
 201         while (1) {
 202                 cfs_time_t this_ping = cfs_time_current();
 203                 struct l_wait_info lwi;
 204                 cfs_duration_t time_to_next_wake;
 205                 cfs_time_t time_of_next_wake;
 206                 struct timeout_item *item;
 207                 struct list_head *iter;
 208
 209                 time_to_next_wake = cfs_time_seconds(PING_INTERVAL);
 210                 time_of_next_wake = cfs_time_shift(PING_INTERVAL);
 211
 212                 mutex_down(&pinger_sem);
 213                 list_for_each_entry(item, &timeout_list, ti_chain) {
 214                         item->ti_cb(item, item->ti_cb_data);
 215                 }
 216                 list_for_each(iter, &pinger_imports) {
 217                         struct obd_import *imp =
 218                                 list_entry(iter, struct obd_import,
 219                                            imp_pinger_chain);
 220                         int force, level;
 221
 222                         spin_lock(&imp->imp_lock);
 223                         level = imp->imp_state;
 224                         force = imp->imp_force_verify;
 225                         imp->imp_force_verify = 0;
 226                         spin_unlock(&imp->imp_lock);
 227
 228                         CDEBUG(level == LUSTRE_IMP_FULL ? D_INFO : D_RPCTRACE,
 229                                "level %s/%u force %u deactive %u pingable %u\n",
 230                                ptlrpc_import_state_name(level), level,
 231                                force, imp->imp_deactive, imp->imp_pingable);
 232
 233                         /* Include any ping which misses the deadline by up to
 234                          * 1/10 of a second.  The pings are designed to clump
 235                          * and this helps ensure the entire batch gets sent
 236                          * promptly, which minimizes system noise from pings */
 237
 238                         if (force ||
 239                             cfs_time_aftereq(this_ping, imp->imp_next_ping -
 240                                              (cfs_time_seconds(1) + 9) / 10)) {
 241                                 if (level == LUSTRE_IMP_DISCON &&
 242                                     !imp_is_deactive(imp)) {
 243                                         ptlrpc_update_next_ping(imp, 0);
 244                                         ptlrpc_initiate_recovery(imp);
 245                                 } else if (level != LUSTRE_IMP_FULL ||
 246                                          imp->imp_obd->obd_no_recov ||
 247                                          imp_is_deactive(imp)) {
 248                                         CDEBUG(D_HA, "not pinging %s "
 249                                                "(in recovery: %s or recovery "
 250                                                "disabled: %u/%u)\n",
 251                                                obd2cli_tgt(imp->imp_obd),
 252                                                ptlrpc_import_state_name(level),
 253                                                imp->imp_deactive,
 254                                                imp->imp_obd->obd_no_recov);
 255                                 } else if (imp->imp_pingable || force) {
 256                                                 ptlrpc_ping(imp);
 257                                                 /* ptlrpc_pinger_sending_on_import()
 258                                                  * will asynch update imp_next_ping
 259                                                  * so it must not be used below to
 260                                                  * calculate minimum wait time. */
 261                                                 continue;
 262                                 }
 263                         } else {
 264                                 if (!imp->imp_pingable)
 265                                         continue;
 266                                 CDEBUG(D_INFO,
 267                                        "don't need to ping %s ("CFS_TIME_T
 268                                        " > "CFS_TIME_T")\n",
 269                                        obd2cli_tgt(imp->imp_obd),
 270                                        imp->imp_next_ping, this_ping);
 271                         }
 272
 273                         /* Wait time until next ping, or until we stopped. */
 274                         if (cfs_time_before(imp->imp_next_ping,
 275                                             time_of_next_wake)) {
 276                                 time_of_next_wake = imp->imp_next_ping;
 277                                 time_to_next_wake = max_t(cfs_duration_t,
 278                                         cfs_time_seconds(1),
 279                                         cfs_time_sub(time_of_next_wake,
 280                                                      cfs_time_current()));
 281                         }
 282                 }
 283                 mutex_up(&pinger_sem);
 284                 obd_update_maxusage();
 285                 CDEBUG(D_INFO, "next ping in "CFS_DURATION_T" ("CFS_TIME_T")\n",
 286                                time_to_next_wake, time_of_next_wake);
 287
 288                 if (time_to_next_wake > 0) {
 289                         lwi = LWI_TIMEOUT(time_to_next_wake, NULL, NULL);
 290                         l_wait_event(thread->t_ctl_waitq,
 291                                      thread->t_flags & (SVC_STOPPING|SVC_EVENT),
 292                                      &lwi);
 293                         if (thread->t_flags & SVC_STOPPING) {
 294                                 thread->t_flags &= ~SVC_STOPPING;
 295                                 EXIT;
 296                                 break;
 297                         } else if (thread->t_flags & SVC_EVENT) {
 298                                 /* woken after adding import to reset timer */
 299                                 thread->t_flags &= ~SVC_EVENT;
 300                         }
 301                 }
 302         }
 303
 304         thread->t_flags = SVC_STOPPED;
 305         cfs_waitq_signal(&thread->t_ctl_waitq);
 306
 307         CDEBUG(D_NET, "pinger thread exiting, process %d\n", cfs_curproc_pid());
 308         return 0;
 309 }
 310
 311 static struct ptlrpc_thread *pinger_thread = NULL;
 312
 313 int ptlrpc_start_pinger(void)
 314 {
 315         struct l_wait_info lwi = { 0 };
 316         struct ptlrpc_svc_data d;
 317         int rc;
 318 #ifndef ENABLE_PINGER
 319         return 0;
 320 #endif
 321         ENTRY;
 322
 323         if (pinger_thread != NULL)
 324                 RETURN(-EALREADY);
 325
 326         OBD_ALLOC(pinger_thread, sizeof(*pinger_thread));
 327         if (pinger_thread == NULL)
 328                 RETURN(-ENOMEM);
 329         cfs_waitq_init(&pinger_thread->t_ctl_waitq);
 330
 331         d.name = "ll_ping";
 332         d.thread = pinger_thread;
 333
 334         /* CLONE_VM and CLONE_FILES just avoid a needless copy, because we
 335          * just drop the VM and FILES in cfs_daemonize_ctxt() right away. */
 336         rc = cfs_kernel_thread(ptlrpc_pinger_main, &d, CLONE_VM | CLONE_FILES);
 337         if (rc < 0) {
 338                 CERROR("cannot start thread: %d\n", rc);
 339                 OBD_FREE(pinger_thread, sizeof(*pinger_thread));
 340                 pinger_thread = NULL;
 341                 RETURN(rc);
 342         }
 343         l_wait_event(pinger_thread->t_ctl_waitq,
 344                      pinger_thread->t_flags & SVC_RUNNING, &lwi);
 345
 346         RETURN(0);
 347 }
 348
 349 int ptlrpc_pinger_remove_timeouts(void);
 350
 351 int ptlrpc_stop_pinger(void)
 352 {
 353         struct l_wait_info lwi = { 0 };
 354         int rc = 0;
 355 #ifndef ENABLE_PINGER
 356         return 0;
 357 #endif
 358         ENTRY;
 359
 360         if (pinger_thread == NULL)
 361                 RETURN(-EALREADY);
 362
 363         ptlrpc_pinger_remove_timeouts();
 364         mutex_down(&pinger_sem);
 365         pinger_thread->t_flags = SVC_STOPPING;
 366         cfs_waitq_signal(&pinger_thread->t_ctl_waitq);
 367         mutex_up(&pinger_sem);
 368
 369         l_wait_event(pinger_thread->t_ctl_waitq,
 370                      (pinger_thread->t_flags & SVC_STOPPED), &lwi);
 371
 372         OBD_FREE(pinger_thread, sizeof(*pinger_thread));
 373         pinger_thread = NULL;
 374         RETURN(rc);
 375 }
 376
 377 void ptlrpc_pinger_sending_on_import(struct obd_import *imp)
 378 {
 379         ptlrpc_update_next_ping(imp, 0);
 380 }
 381
 382 void ptlrpc_pinger_commit_expected(struct obd_import *imp)
 383 {
 384         ptlrpc_update_next_ping(imp, 1);
 385 }
 386
 387 int ptlrpc_pinger_add_import(struct obd_import *imp)
 388 {
 389         ENTRY;
 390         if (!list_empty(&imp->imp_pinger_chain))
 391                 RETURN(-EALREADY);
 392
 393         mutex_down(&pinger_sem);
 394         CDEBUG(D_HA, "adding pingable import %s->%s\n",
 395                imp->imp_obd->obd_uuid.uuid, obd2cli_tgt(imp->imp_obd));
 396         /* if we add to pinger we want recovery on this import */
 397         imp->imp_obd->obd_no_recov = 0;
 398
 399         ptlrpc_update_next_ping(imp, 0);
 400         /* XXX sort, blah blah */
 401         list_add_tail(&imp->imp_pinger_chain, &pinger_imports);
 402         class_import_get(imp);
 403
 404         ptlrpc_pinger_wake_up();
 405         mutex_up(&pinger_sem);
 406
 407         RETURN(0);
 408 }
 409
 410 int ptlrpc_pinger_del_import(struct obd_import *imp)
 411 {
 412         ENTRY;
 413         if (list_empty(&imp->imp_pinger_chain))
 414                 RETURN(-ENOENT);
 415
 416         mutex_down(&pinger_sem);
 417         list_del_init(&imp->imp_pinger_chain);
 418         CDEBUG(D_HA, "removing pingable import %s->%s\n",
 419                imp->imp_obd->obd_uuid.uuid, obd2cli_tgt(imp->imp_obd));
 420         /* if we remove from pinger we don't want recovery on this import */
 421         imp->imp_obd->obd_no_recov = 1;
 422         class_import_put(imp);
 423         mutex_up(&pinger_sem);
 424         RETURN(0);
 425 }
 426
 427 /**
 428  * Register a timeout callback to the pinger list, and the callback will
 429  * be called when timeout happens.
 430  */
 431 struct timeout_item* ptlrpc_new_timeout(int time, enum timeout_event event,
 432                                         timeout_cb_t cb, void *data)
 433 {
 434         struct timeout_item *ti;
 435
 436         OBD_ALLOC_PTR(ti);
 437         if (!ti)
 438                 return(NULL);
 439
 440         CFS_INIT_LIST_HEAD(&ti->ti_obd_list);
 441         CFS_INIT_LIST_HEAD(&ti->ti_chain);
 442         ti->ti_timeout = time;
 443         ti->ti_event = event;
 444         ti->ti_cb = cb;
 445         ti->ti_cb_data = data;
 446
 447         return ti;
 448 }
 449
 450 /**
 451  * Register timeout event on the the pinger thread.
 452  * Note: the timeout list is an sorted list with increased timeout value.
 453  */
 454 static struct timeout_item*
 455 ptlrpc_pinger_register_timeout(int time, enum timeout_event event,
 456                                timeout_cb_t cb, void *data)
 457 {
 458         struct timeout_item *item, *tmp;
 459
 460         LASSERT_SEM_LOCKED(&pinger_sem);
 461
 462         list_for_each_entry(item, &timeout_list, ti_chain)
 463                 if (item->ti_event == event)
 464                         goto out;
 465
 466         item = ptlrpc_new_timeout(time, event, cb, data);
 467         if (item) {
 468                 list_for_each_entry_reverse(tmp, &timeout_list, ti_chain) {
 469                         if (tmp->ti_timeout < time) {
 470                                 list_add(&item->ti_chain, &tmp->ti_chain);
 471                                 goto out;
 472                         }
 473                 }
 474                 list_add(&item->ti_chain, &timeout_list);
 475         }
 476 out:
 477         return item;
 478 }
 479
 480 /* Add a client_obd to the timeout event list, when timeout(@time)
 481  * happens, the callback(@cb) will be called.
 482  */
 483 int ptlrpc_add_timeout_client(int time, enum timeout_event event,
 484                               timeout_cb_t cb, void *data,
 485                               struct list_head *obd_list)
 486 {
 487         struct timeout_item *ti;
 488
 489         mutex_down(&pinger_sem);
 490         ti = ptlrpc_pinger_register_timeout(time, event, cb, data);
 491         if (!ti) {
 492                 mutex_up(&pinger_sem);
 493                 return (-EINVAL);
 494         }
 495         list_add(obd_list, &ti->ti_obd_list);
 496         mutex_up(&pinger_sem);
 497         return 0;
 498 }
 499
 500 int ptlrpc_del_timeout_client(struct list_head *obd_list,
 501                               enum timeout_event event)
 502 {
 503         struct timeout_item *ti = NULL, *item;
 504
 505         if (list_empty(obd_list))
 506                 return 0;
 507         mutex_down(&pinger_sem);
 508         list_del_init(obd_list);
 509         /**
 510          * If there are no obd attached to the timeout event
 511          * list, remove this timeout event from the pinger
 512          */
 513         list_for_each_entry(item, &timeout_list, ti_chain) {
 514                 if (item->ti_event == event) {
 515                         ti = item;
 516                         break;
 517                 }
 518         }
 519         LASSERTF(ti != NULL, "ti is NULL ! \n");
 520         if (list_empty(&ti->ti_obd_list)) {
 521                 list_del(&ti->ti_chain);
 522                 OBD_FREE_PTR(ti);
 523         }
 524         mutex_up(&pinger_sem);
 525         return 0;
 526 }
 527
 528 int ptlrpc_pinger_remove_timeouts(void)
 529 {
 530         struct timeout_item *item, *tmp;
 531
 532         mutex_down(&pinger_sem);
 533         list_for_each_entry_safe(item, tmp, &timeout_list, ti_chain) {
 534                 LASSERT(list_empty(&item->ti_obd_list));
 535                 list_del(&item->ti_chain);
 536                 OBD_FREE_PTR(item);
 537         }
 538         mutex_up(&pinger_sem);
 539         return 0;
 540 }
 541
 542 void ptlrpc_pinger_wake_up()
 543 {
 544 #ifdef ENABLE_PINGER
 545         pinger_thread->t_flags |= SVC_EVENT;
 546         cfs_waitq_signal(&pinger_thread->t_ctl_waitq);
 547 #endif
 548 }
 549
 550 /* Ping evictor thread */
 551 #define PET_READY     1
 552 #define PET_TERMINATE 2
 553
 554 static int               pet_refcount = 0;
 555 static int               pet_state;
 556 static wait_queue_head_t pet_waitq;
 557 CFS_LIST_HEAD(pet_list);
 558 static spinlock_t        pet_lock = SPIN_LOCK_UNLOCKED;
 559
 560 int ping_evictor_wake(struct obd_export *exp)
 561 {
 562         struct obd_device *obd;
 563
 564         spin_lock(&pet_lock);
 565         if (pet_state != PET_READY) {
 566                 /* eventually the new obd will call here again. */
 567                 spin_unlock(&pet_lock);
 568                 return 1;
 569         }
 570
 571         obd = class_exp2obd(exp);
 572         if (list_empty(&obd->obd_evict_list)) {
 573                 class_incref(obd);
 574                 list_add(&obd->obd_evict_list, &pet_list);
 575         }
 576         spin_unlock(&pet_lock);
 577
 578         wake_up(&pet_waitq);
 579         return 0;
 580 }
 581
 582 static int ping_evictor_main(void *arg)
 583 {
 584         struct obd_device *obd;
 585         struct obd_export *exp;
 586         struct l_wait_info lwi = { 0 };
 587         time_t expire_time;
 588         ENTRY;
 589
 590         cfs_daemonize_ctxt("ll_evictor");
 591
 592         CDEBUG(D_HA, "Starting Ping Evictor\n");
 593         pet_state = PET_READY;
 594         while (1) {
 595                 l_wait_event(pet_waitq, (!list_empty(&pet_list)) ||
 596                              (pet_state == PET_TERMINATE), &lwi);
 597
 598                 /* loop until all obd's will be removed */
 599                 if ((pet_state == PET_TERMINATE) && list_empty(&pet_list))
 600                         break;
 601
 602                 /* we only get here if pet_exp != NULL, and the end of this
 603                  * loop is the only place which sets it NULL again, so lock
 604                  * is not strictly necessary. */
 605                 spin_lock(&pet_lock);
 606                 obd = list_entry(pet_list.next, struct obd_device,
 607                                  obd_evict_list);
 608                 spin_unlock(&pet_lock);
 609
 610                 /* bug 18948: ensure recovery is aborted in a timely fashion */
 611                 if (target_recovery_check_and_stop(obd) ||
 612                     obd->obd_recovering /* no evictor during recovery */)
 613                        GOTO(skip, 0);
 614
 615                 expire_time = cfs_time_current_sec() - PING_EVICT_TIMEOUT;
 616
 617                 CDEBUG(D_HA, "evicting all exports of obd %s older than %ld\n",
 618                        obd->obd_name, expire_time);
 619
 620                 /* Exports can't be deleted out of the list while we hold
 621                  * the obd lock (class_unlink_export), which means we can't
 622                  * lose the last ref on the export.  If they've already been
 623                  * removed from the list, we won't find them here. */
 624                 spin_lock(&obd->obd_dev_lock);
 625                 while (!list_empty(&obd->obd_exports_timed)) {
 626                         exp = list_entry(obd->obd_exports_timed.next,
 627                                          struct obd_export,exp_obd_chain_timed);
 628                         if (expire_time > exp->exp_last_request_time) {
 629                                 class_export_get(exp);
 630                                 spin_unlock(&obd->obd_dev_lock);
 631                                 LCONSOLE_WARN("%s: haven't heard from client %s"
 632                                               " (at %s) in %ld seconds. I think"
 633                                               " it's dead, and I am evicting"
 634                                               " it.\n", obd->obd_name,
 635                                               obd_uuid2str(&exp->exp_client_uuid),
 636                                               obd_export_nid2str(exp),
 637                                               (long)(cfs_time_current_sec() -
 638                                                      exp->exp_last_request_time));
 639                                 CDEBUG(D_HA, "Last request was at %ld\n",
 640                                        exp->exp_last_request_time);
 641                                 class_fail_export(exp);
 642                                 class_export_put(exp);
 643                                 spin_lock(&obd->obd_dev_lock);
 644                         } else {
 645                                 /* List is sorted, so everyone below is ok */
 646                                 break;
 647                         }
 648                 }
 649                 spin_unlock(&obd->obd_dev_lock);
 650 skip:
 651                 spin_lock(&pet_lock);
 652                 list_del_init(&obd->obd_evict_list);
 653                 spin_unlock(&pet_lock);
 654
 655                 class_decref(obd);
 656         }
 657
 658         CDEBUG(D_HA, "Exiting Ping Evictor\n");
 659
 660         RETURN(0);
 661 }
 662
 663 void ping_evictor_start(void)
 664 {
 665         int rc;
 666
 667         if (++pet_refcount > 1)
 668                 return;
 669
 670         init_waitqueue_head(&pet_waitq);
 671
 672         rc = cfs_kernel_thread(ping_evictor_main, NULL, CLONE_VM | CLONE_FILES);
 673         if (rc < 0) {
 674                 pet_refcount--;
 675                 CERROR("Cannot start ping evictor thread: %d\n", rc);
 676         }
 677 }
 678 EXPORT_SYMBOL(ping_evictor_start);
 679
 680 void ping_evictor_stop(void)
 681 {
 682         if (--pet_refcount > 0)
 683                 return;
 684
 685         pet_state = PET_TERMINATE;
 686         wake_up(&pet_waitq);
 687 }
 688 EXPORT_SYMBOL(ping_evictor_stop);
 689 #else /* !__KERNEL__ */
 690
 691 /* XXX
 692  * the current implementation of pinger in liblustre is not optimized
 693  */
 694
 695 #ifdef ENABLE_PINGER
 696 static struct pinger_data {
 697         int             pd_recursion;
 698         cfs_time_t      pd_this_ping;   /* jiffies */
 699         cfs_time_t      pd_next_ping;   /* jiffies */
 700         struct ptlrpc_request_set *pd_set;
 701 } pinger_args;
 702
 703 static int pinger_check_rpcs(void *arg)
 704 {
 705         cfs_time_t curtime = cfs_time_current();
 706         struct ptlrpc_request *req;
 707         struct ptlrpc_request_set *set;
 708         struct list_head *iter;
 709         struct obd_import *imp;
 710         struct pinger_data *pd = &pinger_args;
 711         int rc;
 712
 713         /* prevent recursion */
 714         if (pd->pd_recursion++) {
 715                 CDEBUG(D_HA, "pinger: recursion! quit\n");
 716                 LASSERT(pd->pd_set);
 717                 pd->pd_recursion--;
 718                 return 0;
 719         }
 720
 721         /* have we reached ping point? */
 722         if (!pd->pd_set && time_before(curtime, pd->pd_next_ping)) {
 723                 pd->pd_recursion--;
 724                 return 0;
 725         }
 726
 727         /* if we have rpc_set already, continue processing it */
 728         if (pd->pd_set) {
 729                 LASSERT(pd->pd_this_ping);
 730                 set = pd->pd_set;
 731                 goto do_check_set;
 732         }
 733
 734         pd->pd_this_ping = curtime;
 735         pd->pd_set = ptlrpc_prep_set();
 736         if (pd->pd_set == NULL)
 737                 goto out;
 738         set = pd->pd_set;
 739
 740         /* add rpcs into set */
 741         mutex_down(&pinger_sem);
 742         list_for_each(iter, &pinger_imports) {
 743                 struct obd_import *imp =
 744                         list_entry(iter, struct obd_import, imp_pinger_chain);
 745                 int generation, level;
 746
 747                 /* Include any ping within 1/10 of a second of the deadline */
 748                 if (cfs_time_aftereq(pd->pd_this_ping, imp->imp_next_ping -
 749                                      (cfs_time_seconds(1) + 9) / 10)) {
 750                         /* Add a ping. */
 751                         spin_lock(&imp->imp_lock);
 752                         generation = imp->imp_generation;
 753                         level = imp->imp_state;
 754                         spin_unlock(&imp->imp_lock);
 755
 756                         if (level != LUSTRE_IMP_FULL) {
 757                                 CDEBUG(D_HA,
 758                                        "not pinging %s (in recovery)\n",
 759                                        obd2cli_tgt(imp->imp_obd));
 760                                 continue;
 761                         }
 762
 763                         req = ptlrpc_prep_req(imp, LUSTRE_OBD_VERSION, OBD_PING,
 764                                               1, NULL, NULL);
 765                         if (!req) {
 766                                 CERROR("out of memory\n");
 767                                 break;
 768                         }
 769                         req->rq_no_resend = 1;
 770                         ptlrpc_req_set_repsize(req, 1, NULL);
 771                         req->rq_send_state = LUSTRE_IMP_FULL;
 772                         ptlrpc_rqphase_move(req, RQ_PHASE_RPC);
 773                         req->rq_import_generation = generation;
 774                         ptlrpc_set_add_req(set, req);
 775                 } else {
 776                         CDEBUG(D_INFO, "don't need to ping %s ("CFS_TIME_T
 777                                " > "CFS_TIME_T")\n", obd2cli_tgt(imp->imp_obd),
 778                                imp->imp_next_ping, pd->pd_this_ping);
 779                 }
 780         }
 781         pd->pd_this_ping = curtime;
 782         mutex_up(&pinger_sem);
 783
 784         /* Might be empty, that's OK. */
 785         if (set->set_remaining == 0)
 786                 CDEBUG(D_RPCTRACE, "nothing to ping\n");
 787
 788         list_for_each(iter, &set->set_requests) {
 789                 struct ptlrpc_request *req =
 790                         list_entry(iter, struct ptlrpc_request,
 791                                    rq_set_chain);
 792                 DEBUG_REQ(D_RPCTRACE, req, "pinging %s->%s",
 793                           req->rq_import->imp_obd->obd_uuid.uuid,
 794                           obd2cli_tgt(req->rq_import->imp_obd));
 795                 (void)ptl_send_rpc(req, 0);
 796         }
 797
 798 do_check_set:
 799         rc = ptlrpc_check_set(set);
 800
 801         /* not finished, and we are not expired, simply return */
 802         if (!rc && cfs_time_before(curtime, cfs_time_add(pd->pd_this_ping,
 803                                             cfs_time_seconds(PING_INTERVAL)))) {
 804                 CDEBUG(D_RPCTRACE, "not finished, but also not expired\n");
 805                 pd->pd_recursion--;
 806                 return 0;
 807         }
 808
 809         /* Expire all the requests that didn't come back. */
 810         mutex_down(&pinger_sem);
 811         list_for_each(iter, &set->set_requests) {
 812                 req = list_entry(iter, struct ptlrpc_request,
 813                                  rq_set_chain);
 814
 815                 if (req->rq_phase == RQ_PHASE_COMPLETE)
 816                         continue;
 817
 818                 CDEBUG(D_RPCTRACE, "Pinger initiate expire request(%p)\n",
 819                        req);
 820
 821                 /* This will also unregister reply. */
 822                 ptlrpc_expire_one_request(req, 0);
 823
 824                 /* We're done with this req, let's finally move it to complete
 825                  * phase and take care of inflights. */
 826                 ptlrpc_rqphase_move(req, RQ_PHASE_COMPLETE);
 827                 imp = req->rq_import;
 828                 spin_lock(&imp->imp_lock);
 829                 if (!list_empty(&req->rq_list)) {
 830                         list_del_init(&req->rq_list);
 831                         atomic_dec(&imp->imp_inflight);
 832                 }
 833                 spin_unlock(&imp->imp_lock);
 834                 set->set_remaining--;
 835         }
 836         mutex_up(&pinger_sem);
 837
 838         ptlrpc_set_destroy(set);
 839         pd->pd_set = NULL;
 840
 841 out:
 842         pd->pd_next_ping = cfs_time_add(pd->pd_this_ping,
 843                                         cfs_time_seconds(PING_INTERVAL));
 844         pd->pd_this_ping = 0; /* XXX for debug */
 845
 846         CDEBUG(D_INFO, "finished a round ping\n");
 847         pd->pd_recursion--;
 848         return 0;
 849 }
 850
 851 static void *pinger_callback = NULL;
 852 #endif /* ENABLE_PINGER */
 853
 854 int ptlrpc_start_pinger(void)
 855 {
 856 #ifdef ENABLE_PINGER
 857         memset(&pinger_args, 0, sizeof(pinger_args));
 858         pinger_callback = liblustre_register_wait_callback("pinger_check_rpcs",
 859                                                            &pinger_check_rpcs,
 860                                                            &pinger_args);
 861 #endif
 862         return 0;
 863 }
 864
 865 int ptlrpc_stop_pinger(void)
 866 {
 867 #ifdef ENABLE_PINGER
 868         if (pinger_callback)
 869                 liblustre_deregister_wait_callback(pinger_callback);
 870 #endif
 871         return 0;
 872 }
 873
 874 void ptlrpc_pinger_sending_on_import(struct obd_import *imp)
 875 {
 876 #ifdef ENABLE_PINGER
 877         mutex_down(&pinger_sem);
 878         ptlrpc_update_next_ping(imp, 0);
 879         if (pinger_args.pd_set == NULL &&
 880             time_before(imp->imp_next_ping, pinger_args.pd_next_ping)) {
 881                 CDEBUG(D_HA, "set next ping to "CFS_TIME_T"(cur "CFS_TIME_T")\n",
 882                         imp->imp_next_ping, cfs_time_current());
 883                 pinger_args.pd_next_ping = imp->imp_next_ping;
 884         }
 885         mutex_up(&pinger_sem);
 886 #endif
 887 }
 888
 889 int ptlrpc_add_timeout_client(int time, enum timeout_event event,
 890                               timeout_cb_t cb, void *data,
 891                               struct list_head *obd_list)
 892 {
 893         return 0;
 894 }
 895
 896 int ptlrpc_del_timeout_client(struct list_head *obd_list,
 897                               enum timeout_event event)
 898 {
 899         return 0;
 900 }
 901
 902 int ptlrpc_pinger_add_import(struct obd_import *imp)
 903 {
 904         ENTRY;
 905         if (!list_empty(&imp->imp_pinger_chain))
 906                 RETURN(-EALREADY);
 907
 908         CDEBUG(D_HA, "adding pingable import %s->%s\n",
 909                imp->imp_obd->obd_uuid.uuid, obd2cli_tgt(imp->imp_obd));
 910         ptlrpc_pinger_sending_on_import(imp);
 911
 912         mutex_down(&pinger_sem);
 913         list_add_tail(&imp->imp_pinger_chain, &pinger_imports);
 914         class_import_get(imp);
 915         mutex_up(&pinger_sem);
 916
 917         RETURN(0);
 918 }
 919
 920 int ptlrpc_pinger_del_import(struct obd_import *imp)
 921 {
 922         ENTRY;
 923         if (list_empty(&imp->imp_pinger_chain))
 924                 RETURN(-ENOENT);
 925
 926         mutex_down(&pinger_sem);
 927         list_del_init(&imp->imp_pinger_chain);
 928         CDEBUG(D_HA, "removing pingable import %s->%s\n",
 929                imp->imp_obd->obd_uuid.uuid, obd2cli_tgt(imp->imp_obd));
 930         class_import_put(imp);
 931         mutex_up(&pinger_sem);
 932         RETURN(0);
 933 }
 934
 935 void ptlrpc_pinger_wake_up()
 936 {
 937 #ifdef ENABLE_PINGER
 938         ENTRY;
 939         /* XXX force pinger to run, if needed */
 940         struct obd_import *imp;
 941         list_for_each_entry(imp, &pinger_imports, imp_pinger_chain) {
 942                 CDEBUG(D_RPCTRACE, "checking import %s->%s\n",
 943                        imp->imp_obd->obd_uuid.uuid, obd2cli_tgt(imp->imp_obd));
 944 #ifdef ENABLE_LIBLUSTRE_RECOVERY
 945                 if (imp->imp_state == LUSTRE_IMP_DISCON &&
 946                     !imp_is_deactive(imp))
 947 #else
 948                 /*XXX only recover for the initial connection */
 949                 if (!lustre_handle_is_used(&imp->imp_remote_handle) &&
 950                     imp->imp_state == LUSTRE_IMP_DISCON &&
 951                     !imp_is_deactive(imp))
 952 #endif
 953                         ptlrpc_initiate_recovery(imp);
 954                 else if (imp->imp_state != LUSTRE_IMP_FULL)
 955                         CDEBUG(D_HA, "Refused to recover import %s->%s "
 956                                      "state %d, deactive %d\n",
 957                                      imp->imp_obd->obd_uuid.uuid,
 958                                      obd2cli_tgt(imp->imp_obd), imp->imp_state,
 959                                      imp_is_deactive(imp));
 960         }
 961 #endif
 962         EXIT;
 963 }
 964 #endif /* !__KERNEL__ */