lustre/ptlrpc/service.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
  37 #define DEBUG_SUBSYSTEM S_RPC
  38 #ifndef __KERNEL__
  39 #include <liblustre.h>
  40 #endif
  41 #include <obd_support.h>
  42 #include <obd_class.h>
  43 #include <lustre_net.h>
  44 #include <lu_object.h>
  45 #include <lnet/types.h>
  46 #include "ptlrpc_internal.h"
  47
  48 /* The following are visible and mutable through /sys/module/ptlrpc */
  49 int test_req_buffer_pressure = 0;
  50 CFS_MODULE_PARM(test_req_buffer_pressure, "i", int, 0444,
  51                 "set non-zero to put pressure on request buffer pools");
  52 unsigned int at_min = 0;
  53 CFS_MODULE_PARM(at_min, "i", int, 0644,
  54                 "Adaptive timeout minimum (sec)");
  55 unsigned int at_max = 600;
  56 EXPORT_SYMBOL(at_max);
  57 CFS_MODULE_PARM(at_max, "i", int, 0644,
  58                 "Adaptive timeout maximum (sec)");
  59 unsigned int at_history = 600;
  60 CFS_MODULE_PARM(at_history, "i", int, 0644,
  61                 "Adaptive timeouts remember the slowest event that took place "
  62                 "within this period (sec)");
  63 static int at_early_margin = 5;
  64 CFS_MODULE_PARM(at_early_margin, "i", int, 0644,
  65                 "How soon before an RPC deadline to send an early reply");
  66 static int at_extra = 30;
  67 CFS_MODULE_PARM(at_extra, "i", int, 0644,
  68                 "How much extra time to give with each early reply");
  69
  70
  71 /* forward ref */
  72 static int ptlrpc_server_post_idle_rqbds (struct ptlrpc_service *svc);
  73
  74 static CFS_LIST_HEAD(ptlrpc_all_services);
  75 spinlock_t ptlrpc_all_services_lock;
  76
  77 static char *
  78 ptlrpc_alloc_request_buffer (int size)
  79 {
  80         char *ptr;
  81
  82         if (size > SVC_BUF_VMALLOC_THRESHOLD)
  83                 OBD_VMALLOC(ptr, size);
  84         else
  85                 OBD_ALLOC(ptr, size);
  86
  87         return (ptr);
  88 }
  89
  90 static void
  91 ptlrpc_free_request_buffer (char *ptr, int size)
  92 {
  93         if (size > SVC_BUF_VMALLOC_THRESHOLD)
  94                 OBD_VFREE(ptr, size);
  95         else
  96                 OBD_FREE(ptr, size);
  97 }
  98
  99 struct ptlrpc_request_buffer_desc *
 100 ptlrpc_alloc_rqbd (struct ptlrpc_service *svc)
 101 {
 102         struct ptlrpc_request_buffer_desc *rqbd;
 103
 104         OBD_ALLOC_PTR(rqbd);
 105         if (rqbd == NULL)
 106                 return (NULL);
 107
 108         rqbd->rqbd_service = svc;
 109         rqbd->rqbd_refcount = 0;
 110         rqbd->rqbd_cbid.cbid_fn = request_in_callback;
 111         rqbd->rqbd_cbid.cbid_arg = rqbd;
 112         CFS_INIT_LIST_HEAD(&rqbd->rqbd_reqs);
 113         rqbd->rqbd_buffer = ptlrpc_alloc_request_buffer(svc->srv_buf_size);
 114
 115         if (rqbd->rqbd_buffer == NULL) {
 116                 OBD_FREE_PTR(rqbd);
 117                 return (NULL);
 118         }
 119
 120         spin_lock(&svc->srv_lock);
 121         list_add(&rqbd->rqbd_list, &svc->srv_idle_rqbds);
 122         svc->srv_nbufs++;
 123         spin_unlock(&svc->srv_lock);
 124
 125         return (rqbd);
 126 }
 127
 128 void
 129 ptlrpc_free_rqbd (struct ptlrpc_request_buffer_desc *rqbd)
 130 {
 131         struct ptlrpc_service *svc = rqbd->rqbd_service;
 132
 133         LASSERT (rqbd->rqbd_refcount == 0);
 134         LASSERT (list_empty(&rqbd->rqbd_reqs));
 135
 136         spin_lock(&svc->srv_lock);
 137         list_del(&rqbd->rqbd_list);
 138         svc->srv_nbufs--;
 139         spin_unlock(&svc->srv_lock);
 140
 141         ptlrpc_free_request_buffer (rqbd->rqbd_buffer, svc->srv_buf_size);
 142         OBD_FREE_PTR(rqbd);
 143 }
 144
 145 int
 146 ptlrpc_grow_req_bufs(struct ptlrpc_service *svc)
 147 {
 148         struct ptlrpc_request_buffer_desc *rqbd;
 149         int                                i;
 150
 151         CDEBUG(D_RPCTRACE, "%s: allocate %d new %d-byte reqbufs (%d/%d left)\n",
 152                svc->srv_name, svc->srv_nbuf_per_group, svc->srv_buf_size,
 153                svc->srv_nrqbd_receiving, svc->srv_nbufs);
 154         for (i = 0; i < svc->srv_nbuf_per_group; i++) {
 155                 rqbd = ptlrpc_alloc_rqbd(svc);
 156
 157                 if (rqbd == NULL) {
 158                         CERROR ("%s: Can't allocate request buffer\n",
 159                                 svc->srv_name);
 160                         return (-ENOMEM);
 161                 }
 162
 163                 if (ptlrpc_server_post_idle_rqbds(svc) < 0)
 164                         return (-EAGAIN);
 165         }
 166
 167         return (0);
 168 }
 169
 170 void
 171 ptlrpc_save_lock (struct ptlrpc_request *req,
 172                   struct lustre_handle *lock, int mode)
 173 {
 174         struct ptlrpc_reply_state *rs = req->rq_reply_state;
 175         int                        idx;
 176
 177         LASSERT(rs != NULL);
 178         LASSERT(rs->rs_nlocks < RS_MAX_LOCKS);
 179
 180         idx = rs->rs_nlocks++;
 181         rs->rs_locks[idx] = *lock;
 182         rs->rs_modes[idx] = mode;
 183         rs->rs_difficult = 1;
 184 }
 185
 186 void
 187 ptlrpc_schedule_difficult_reply (struct ptlrpc_reply_state *rs)
 188 {
 189         struct ptlrpc_service *svc = rs->rs_service;
 190
 191 #ifdef CONFIG_SMP
 192         LASSERT (spin_is_locked (&svc->srv_lock));
 193 #endif
 194         LASSERT (rs->rs_difficult);
 195         rs->rs_scheduled_ever = 1;              /* flag any notification attempt */
 196
 197         if (rs->rs_scheduled)                   /* being set up or already notified */
 198                 return;
 199
 200         rs->rs_scheduled = 1;
 201         list_del (&rs->rs_list);
 202         list_add (&rs->rs_list, &svc->srv_reply_queue);
 203         cfs_waitq_signal (&svc->srv_waitq);
 204 }
 205
 206 void
 207 ptlrpc_commit_replies (struct obd_device *obd)
 208 {
 209         struct list_head   *tmp;
 210         struct list_head   *nxt;
 211
 212         /* Find any replies that have been committed and get their service
 213          * to attend to complete them. */
 214
 215         /* CAVEAT EMPTOR: spinlock ordering!!! */
 216         spin_lock(&obd->obd_uncommitted_replies_lock);
 217
 218         list_for_each_safe (tmp, nxt, &obd->obd_uncommitted_replies) {
 219                 struct ptlrpc_reply_state *rs =
 220                         list_entry(tmp, struct ptlrpc_reply_state, rs_obd_list);
 221
 222                 LASSERT (rs->rs_difficult);
 223
 224                 if (rs->rs_transno <= obd->obd_last_committed) {
 225                         struct ptlrpc_service *svc = rs->rs_service;
 226
 227                         spin_lock (&svc->srv_lock);
 228                         list_del_init (&rs->rs_obd_list);
 229                         ptlrpc_schedule_difficult_reply (rs);
 230                         spin_unlock (&svc->srv_lock);
 231                 }
 232         }
 233
 234         spin_unlock(&obd->obd_uncommitted_replies_lock);
 235 }
 236
 237 static int
 238 ptlrpc_server_post_idle_rqbds (struct ptlrpc_service *svc)
 239 {
 240         struct ptlrpc_request_buffer_desc *rqbd;
 241         int                                rc;
 242         int                                posted = 0;
 243
 244         for (;;) {
 245                 spin_lock(&svc->srv_lock);
 246
 247                 if (list_empty (&svc->srv_idle_rqbds)) {
 248                         spin_unlock(&svc->srv_lock);
 249                         return (posted);
 250                 }
 251
 252                 rqbd = list_entry(svc->srv_idle_rqbds.next,
 253                                   struct ptlrpc_request_buffer_desc,
 254                                   rqbd_list);
 255                 list_del (&rqbd->rqbd_list);
 256
 257                 /* assume we will post successfully */
 258                 svc->srv_nrqbd_receiving++;
 259                 list_add (&rqbd->rqbd_list, &svc->srv_active_rqbds);
 260
 261                 spin_unlock(&svc->srv_lock);
 262
 263                 rc = ptlrpc_register_rqbd(rqbd);
 264                 if (rc != 0)
 265                         break;
 266
 267                 posted = 1;
 268         }
 269
 270         spin_lock(&svc->srv_lock);
 271
 272         svc->srv_nrqbd_receiving--;
 273         list_del(&rqbd->rqbd_list);
 274         list_add_tail(&rqbd->rqbd_list, &svc->srv_idle_rqbds);
 275
 276         /* Don't complain if no request buffers are posted right now; LNET
 277          * won't drop requests because we set the portal lazy! */
 278
 279         spin_unlock(&svc->srv_lock);
 280
 281         return (-1);
 282 }
 283
 284 struct ptlrpc_service *ptlrpc_init_svc_conf(struct ptlrpc_service_conf *c,
 285                                             svc_handler_t h, char *name,
 286                                             struct proc_dir_entry *proc_entry,
 287                                             svcreq_printfn_t prntfn,
 288                                             char *threadname)
 289 {
 290         return ptlrpc_init_svc(c->psc_nbufs, c->psc_bufsize,
 291                                c->psc_max_req_size, c->psc_max_reply_size,
 292                                c->psc_req_portal, c->psc_rep_portal,
 293                                c->psc_watchdog_factor,
 294                                h, name, proc_entry,
 295                                prntfn, c->psc_min_threads, c->psc_max_threads,
 296                                threadname, c->psc_ctx_tags);
 297 }
 298 EXPORT_SYMBOL(ptlrpc_init_svc_conf);
 299
 300 static void ptlrpc_at_timer(unsigned long castmeharder)
 301 {
 302         struct ptlrpc_service *svc = (struct ptlrpc_service *)castmeharder;
 303         svc->srv_at_check = 1;
 304         svc->srv_at_checktime = cfs_time_current();
 305         cfs_waitq_signal(&svc->srv_waitq);
 306 }
 307
 308 /* @threadname should be 11 characters or less - 3 will be added on */
 309 struct ptlrpc_service *
 310 ptlrpc_init_svc(int nbufs, int bufsize, int max_req_size, int max_reply_size,
 311                 int req_portal, int rep_portal, int watchdog_factor,
 312                 svc_handler_t handler, char *name,
 313                 cfs_proc_dir_entry_t *proc_entry,
 314                 svcreq_printfn_t svcreq_printfn,
 315                 int min_threads, int max_threads,
 316                 char *threadname, __u32 ctx_tags)
 317 {
 318         int                    rc;
 319         struct ptlrpc_service *service;
 320         ENTRY;
 321
 322         LASSERT (nbufs > 0);
 323         LASSERT (bufsize >= max_req_size + SPTLRPC_MAX_PAYLOAD);
 324         LASSERT (ctx_tags != 0);
 325
 326         OBD_ALLOC_PTR(service);
 327         if (service == NULL)
 328                 RETURN(NULL);
 329
 330         /* First initialise enough for early teardown */
 331
 332         service->srv_name = name;
 333         spin_lock_init(&service->srv_lock);
 334         CFS_INIT_LIST_HEAD(&service->srv_threads);
 335         cfs_waitq_init(&service->srv_waitq);
 336
 337         service->srv_nbuf_per_group = test_req_buffer_pressure ? 1 : nbufs;
 338         service->srv_max_req_size = max_req_size + SPTLRPC_MAX_PAYLOAD;
 339         service->srv_buf_size = bufsize;
 340         service->srv_rep_portal = rep_portal;
 341         service->srv_req_portal = req_portal;
 342         service->srv_watchdog_factor = watchdog_factor;
 343         service->srv_handler = handler;
 344         service->srv_request_history_print_fn = svcreq_printfn;
 345         service->srv_request_seq = 1;           /* valid seq #s start at 1 */
 346         service->srv_request_max_cull_seq = 0;
 347         service->srv_threads_min = min_threads;
 348         service->srv_threads_max = max_threads;
 349         service->srv_thread_name = threadname;
 350         service->srv_ctx_tags = ctx_tags;
 351
 352         rc = LNetSetLazyPortal(service->srv_req_portal);
 353         LASSERT (rc == 0);
 354
 355         CFS_INIT_LIST_HEAD(&service->srv_request_queue);
 356         CFS_INIT_LIST_HEAD(&service->srv_idle_rqbds);
 357         CFS_INIT_LIST_HEAD(&service->srv_active_rqbds);
 358         CFS_INIT_LIST_HEAD(&service->srv_history_rqbds);
 359         CFS_INIT_LIST_HEAD(&service->srv_request_history);
 360         CFS_INIT_LIST_HEAD(&service->srv_active_replies);
 361         CFS_INIT_LIST_HEAD(&service->srv_reply_queue);
 362         CFS_INIT_LIST_HEAD(&service->srv_free_rs_list);
 363         cfs_waitq_init(&service->srv_free_rs_waitq);
 364
 365         spin_lock_init(&service->srv_at_lock);
 366         CFS_INIT_LIST_HEAD(&service->srv_req_in_queue);
 367         CFS_INIT_LIST_HEAD(&service->srv_at_list);
 368         cfs_timer_init(&service->srv_at_timer, ptlrpc_at_timer, service);
 369         /* At SOW, service time should be quick; 10s seems generous. If client
 370            timeout is less than this, we'll be sending an early reply. */
 371         at_init(&service->srv_at_estimate, 10, 0);
 372
 373         spin_lock (&ptlrpc_all_services_lock);
 374         list_add (&service->srv_list, &ptlrpc_all_services);
 375         spin_unlock (&ptlrpc_all_services_lock);
 376
 377         /* Now allocate the request buffers */
 378         rc = ptlrpc_grow_req_bufs(service);
 379         /* We shouldn't be under memory pressure at startup, so
 380          * fail if we can't post all our buffers at this time. */
 381         if (rc != 0)
 382                 GOTO(failed, NULL);
 383
 384         /* Now allocate pool of reply buffers */
 385         /* Increase max reply size to next power of two */
 386         service->srv_max_reply_size = 1;
 387         while (service->srv_max_reply_size <
 388                max_reply_size + SPTLRPC_MAX_PAYLOAD)
 389                 service->srv_max_reply_size <<= 1;
 390
 391         if (proc_entry != NULL)
 392                 ptlrpc_lprocfs_register_service(proc_entry, service);
 393
 394         CDEBUG(D_NET, "%s: Started, listening on portal %d\n",
 395                service->srv_name, service->srv_req_portal);
 396
 397         RETURN(service);
 398 failed:
 399         ptlrpc_unregister_service(service);
 400         return NULL;
 401 }
 402
 403 static void ptlrpc_server_req_decref(struct ptlrpc_request *req)
 404 {
 405         struct ptlrpc_request_buffer_desc *rqbd = req->rq_rqbd;
 406
 407         if (!atomic_dec_and_test(&req->rq_refcount))
 408                 return;
 409
 410         sptlrpc_svc_ctx_decref(req);
 411
 412         LASSERT(list_empty(&req->rq_timed_list));
 413         if (req != &rqbd->rqbd_req) {
 414                 /* NB request buffers use an embedded
 415                  * req if the incoming req unlinked the
 416                  * MD; this isn't one of them! */
 417                 OBD_FREE(req, sizeof(*req));
 418         } else {
 419                 struct ptlrpc_service *svc = rqbd->rqbd_service;
 420                 /* schedule request buffer for re-use.
 421                  * NB I can only do this after I've disposed of their
 422                  * reqs; particularly the embedded req */
 423                 spin_lock(&svc->srv_lock);
 424                 list_add_tail(&rqbd->rqbd_list, &svc->srv_idle_rqbds);
 425                 spin_unlock(&svc->srv_lock);
 426         }
 427 }
 428
 429 static void __ptlrpc_server_free_request(struct ptlrpc_request *req)
 430 {
 431         list_del(&req->rq_list);
 432         ptlrpc_req_drop_rs(req);
 433         ptlrpc_server_req_decref(req);
 434 }
 435
 436 static void
 437 ptlrpc_server_free_request(struct ptlrpc_request *req)
 438 {
 439         struct ptlrpc_request_buffer_desc *rqbd = req->rq_rqbd;
 440         struct ptlrpc_service             *svc = rqbd->rqbd_service;
 441         int                                refcount;
 442         struct list_head                  *tmp;
 443         struct list_head                  *nxt;
 444
 445         if (req->rq_phase != RQ_PHASE_NEW) /* incorrect message magic */
 446                 DEBUG_REQ(D_INFO, req, "free req");
 447         spin_lock(&svc->srv_at_lock);
 448         req->rq_sent_final = 1;
 449         list_del_init(&req->rq_timed_list);
 450         spin_unlock(&svc->srv_at_lock);
 451
 452         spin_lock(&svc->srv_lock);
 453
 454         svc->srv_n_active_reqs--;
 455         list_add(&req->rq_list, &rqbd->rqbd_reqs);
 456
 457         refcount = --(rqbd->rqbd_refcount);
 458         if (refcount == 0) {
 459                 /* request buffer is now idle: add to history */
 460                 list_del(&rqbd->rqbd_list);
 461                 list_add_tail(&rqbd->rqbd_list, &svc->srv_history_rqbds);
 462                 svc->srv_n_history_rqbds++;
 463
 464                 /* cull some history?
 465                  * I expect only about 1 or 2 rqbds need to be recycled here */
 466                 while (svc->srv_n_history_rqbds > svc->srv_max_history_rqbds) {
 467                         rqbd = list_entry(svc->srv_history_rqbds.next,
 468                                           struct ptlrpc_request_buffer_desc,
 469                                           rqbd_list);
 470
 471                         list_del(&rqbd->rqbd_list);
 472                         svc->srv_n_history_rqbds--;
 473
 474                         /* remove rqbd's reqs from svc's req history while
 475                          * I've got the service lock */
 476                         list_for_each(tmp, &rqbd->rqbd_reqs) {
 477                                 req = list_entry(tmp, struct ptlrpc_request,
 478                                                  rq_list);
 479                                 /* Track the highest culled req seq */
 480                                 if (req->rq_history_seq >
 481                                     svc->srv_request_max_cull_seq)
 482                                         svc->srv_request_max_cull_seq =
 483                                                 req->rq_history_seq;
 484                                 list_del(&req->rq_history_list);
 485                         }
 486
 487                         spin_unlock(&svc->srv_lock);
 488
 489                         list_for_each_safe(tmp, nxt, &rqbd->rqbd_reqs) {
 490                                 req = list_entry(rqbd->rqbd_reqs.next,
 491                                                  struct ptlrpc_request,
 492                                                  rq_list);
 493                                 __ptlrpc_server_free_request(req);
 494                         }
 495
 496                         spin_lock(&svc->srv_lock);
 497                 }
 498         } else if (req->rq_reply_state && req->rq_reply_state->rs_prealloc) {
 499                  /* If we are low on memory, we are not interested in
 500                     history */
 501                 list_del_init(&req->rq_history_list);
 502                 __ptlrpc_server_free_request(req);
 503         }
 504
 505         spin_unlock(&svc->srv_lock);
 506
 507 }
 508
 509 /* This function makes sure dead exports are evicted in a timely manner.
 510    This function is only called when some export receives a message (i.e.,
 511    the network is up.) */
 512 static void ptlrpc_update_export_timer(struct obd_export *exp, long extra_delay)
 513 {
 514         struct obd_export *oldest_exp;
 515         time_t oldest_time;
 516
 517         ENTRY;
 518
 519         LASSERT(exp);
 520
 521         /* Compensate for slow machines, etc, by faking our request time
 522            into the future.  Although this can break the strict time-ordering
 523            of the list, we can be really lazy here - we don't have to evict
 524            at the exact right moment.  Eventually, all silent exports
 525            will make it to the top of the list. */
 526         exp->exp_last_request_time = max(exp->exp_last_request_time,
 527                                          cfs_time_current_sec() + extra_delay);
 528
 529         CDEBUG(D_HA, "updating export %s at "CFS_TIME_T" exp %p\n",
 530                exp->exp_client_uuid.uuid,
 531                exp->exp_last_request_time, exp);
 532
 533         /* exports may get disconnected from the chain even though the
 534            export has references, so we must keep the spin lock while
 535            manipulating the lists */
 536         spin_lock(&exp->exp_obd->obd_dev_lock);
 537
 538         if (list_empty(&exp->exp_obd_chain_timed)) {
 539                 /* this one is not timed */
 540                 spin_unlock(&exp->exp_obd->obd_dev_lock);
 541                 EXIT;
 542                 return;
 543         }
 544
 545         list_move_tail(&exp->exp_obd_chain_timed,
 546                        &exp->exp_obd->obd_exports_timed);
 547
 548         oldest_exp = list_entry(exp->exp_obd->obd_exports_timed.next,
 549                                 struct obd_export, exp_obd_chain_timed);
 550         oldest_time = oldest_exp->exp_last_request_time;
 551         spin_unlock(&exp->exp_obd->obd_dev_lock);
 552
 553         if (exp->exp_obd->obd_recovering) {
 554                 /* be nice to everyone during recovery */
 555                 EXIT;
 556                 return;
 557         }
 558
 559         /* Note - racing to start/reset the obd_eviction timer is safe */
 560         if (exp->exp_obd->obd_eviction_timer == 0) {
 561                 /* Check if the oldest entry is expired. */
 562                 if (cfs_time_current_sec() > (oldest_time + PING_EVICT_TIMEOUT +
 563                                               extra_delay)) {
 564                         /* We need a second timer, in case the net was down and
 565                          * it just came back. Since the pinger may skip every
 566                          * other PING_INTERVAL (see note in ptlrpc_pinger_main),
 567                          * we better wait for 3. */
 568                         exp->exp_obd->obd_eviction_timer =
 569                                 cfs_time_current_sec() + 3 * PING_INTERVAL;
 570                         CDEBUG(D_HA, "%s: Think about evicting %s from "CFS_TIME_T"\n",
 571                                exp->exp_obd->obd_name, obd_export_nid2str(exp),
 572                                oldest_time);
 573                 }
 574         } else {
 575                 if (cfs_time_current_sec() >
 576                     (exp->exp_obd->obd_eviction_timer + extra_delay)) {
 577                         /* The evictor won't evict anyone who we've heard from
 578                          * recently, so we don't have to check before we start
 579                          * it. */
 580                         if (!ping_evictor_wake(exp))
 581                                 exp->exp_obd->obd_eviction_timer = 0;
 582                 }
 583         }
 584
 585         EXIT;
 586 }
 587
 588 #ifndef __KERNEL__
 589 int lu_context_init(struct lu_context *ctx, __u32 tags)
 590 {
 591         return 0;
 592 }
 593
 594 void lu_context_fini(struct lu_context *ctx)
 595 {
 596 }
 597
 598 void lu_context_enter(struct lu_context *ctx)
 599 {
 600 }
 601
 602 void lu_context_exit(struct lu_context *ctx)
 603 {
 604 }
 605
 606 #endif
 607
 608 static int ptlrpc_check_req(struct ptlrpc_request *req)
 609 {
 610         if (unlikely(lustre_msg_get_conn_cnt(req->rq_reqmsg) <
 611                      req->rq_export->exp_conn_cnt)) {
 612                 DEBUG_REQ(D_ERROR, req,
 613                           "DROPPING req from old connection %d < %d",
 614                           lustre_msg_get_conn_cnt(req->rq_reqmsg),
 615                           req->rq_export->exp_conn_cnt);
 616                 return -EEXIST;
 617         }
 618         if (unlikely(req->rq_export->exp_obd &&
 619                      req->rq_export->exp_obd->obd_fail)) {
 620              /* Failing over, don't handle any more reqs, send
 621                 error response instead. */
 622                 CDEBUG(D_RPCTRACE, "Dropping req %p for failed obd %s\n",
 623                        req, req->rq_export->exp_obd->obd_name);
 624                 req->rq_status = -ENODEV;
 625                 ptlrpc_error(req);
 626                 return -ENODEV;
 627         }
 628
 629         return 0;
 630 }
 631
 632 static void ptlrpc_at_set_timer(struct ptlrpc_service *svc)
 633 {
 634         struct ptlrpc_request *rq;
 635         __s32 next;
 636
 637         spin_lock(&svc->srv_at_lock);
 638         if (list_empty(&svc->srv_at_list)) {
 639                 cfs_timer_disarm(&svc->srv_at_timer);
 640                 spin_unlock(&svc->srv_at_lock);
 641                 return;
 642         }
 643
 644         /* Set timer for closest deadline */
 645         rq = list_entry(svc->srv_at_list.next, struct ptlrpc_request,
 646                         rq_timed_list);
 647         next = (__s32)(rq->rq_deadline - cfs_time_current_sec() -
 648                        at_early_margin);
 649         if (next <= 0)
 650                 ptlrpc_at_timer((unsigned long)svc);
 651         else
 652                 cfs_timer_arm(&svc->srv_at_timer, cfs_time_shift(next));
 653         spin_unlock(&svc->srv_at_lock);
 654         CDEBUG(D_INFO, "armed %s at %+ds\n", svc->srv_name, next);
 655 }
 656
 657 /* Add rpc to early reply check list */
 658 static int ptlrpc_at_add_timed(struct ptlrpc_request *req)
 659 {
 660         struct ptlrpc_service *svc = req->rq_rqbd->rqbd_service;
 661         struct ptlrpc_request *rq;
 662         int found = 0;
 663
 664         if (AT_OFF)
 665                 return(0);
 666
 667         if (req->rq_no_reply)
 668                 return 0;
 669
 670         if ((lustre_msghdr_get_flags(req->rq_reqmsg) & MSGHDR_AT_SUPPORT) == 0)
 671                 return(-ENOSYS);
 672
 673         spin_lock(&svc->srv_at_lock);
 674
 675         if (unlikely(req->rq_sent_final)) {
 676                 spin_unlock(&svc->srv_at_lock);
 677                 return 0;
 678         }
 679
 680         LASSERT(list_empty(&req->rq_timed_list));
 681         /* Add to sorted list.  Presumably latest rpcs will have the latest
 682            deadlines, so search backward. */
 683         list_for_each_entry_reverse(rq, &svc->srv_at_list, rq_timed_list) {
 684                 if (req->rq_deadline > rq->rq_deadline) {
 685                         list_add(&req->rq_timed_list, &rq->rq_timed_list);
 686                         found++;
 687                         break;
 688                 }
 689         }
 690         if (!found)
 691                 /* Add to front if shortest deadline or list empty */
 692                 list_add(&req->rq_timed_list, &svc->srv_at_list);
 693
 694         /* Check if we're the head of the list */
 695         found = (svc->srv_at_list.next == &req->rq_timed_list);
 696
 697         spin_unlock(&svc->srv_at_lock);
 698
 699         if (found)
 700                 ptlrpc_at_set_timer(svc);
 701
 702         return 0;
 703 }
 704
 705 static int ptlrpc_at_send_early_reply(struct ptlrpc_request *req,
 706                                       int extra_time)
 707 {
 708         struct ptlrpc_service *svc = req->rq_rqbd->rqbd_service;
 709         struct ptlrpc_request *reqcopy;
 710         struct lustre_msg *reqmsg;
 711         cfs_duration_t olddl = req->rq_deadline - cfs_time_current_sec();
 712         time_t newdl;
 713         int rc;
 714         ENTRY;
 715
 716         /* deadline is when the client expects us to reply, margin is the
 717            difference between clients' and servers' expectations */
 718         DEBUG_REQ(D_ADAPTTO, req,
 719                   "%ssending early reply (deadline %+lds, margin %+lds) for "
 720                   "%d+%d", AT_OFF ? "AT off - not " : "",
 721                   olddl, olddl - at_get(&svc->srv_at_estimate),
 722                   at_get(&svc->srv_at_estimate), extra_time);
 723
 724         if (AT_OFF)
 725                 RETURN(0);
 726
 727         if (olddl < 0) {
 728                 DEBUG_REQ(D_WARNING, req, "Already past deadline (%+lds), "
 729                           "not sending early reply. Consider increasing "
 730                           "at_early_margin (%d)?", olddl, at_early_margin);
 731
 732                 /* Return an error so we're not re-added to the timed list. */
 733                 RETURN(-ETIMEDOUT);
 734         }
 735
 736         if ((lustre_msghdr_get_flags(req->rq_reqmsg) & MSGHDR_AT_SUPPORT) == 0){
 737                 DEBUG_REQ(D_INFO, req, "Wanted to ask client for more time, "
 738                           "but no AT support");
 739                 RETURN(-ENOSYS);
 740         }
 741
 742         if (extra_time) {
 743                 /* Fake our processing time into the future to ask the
 744                    clients for some extra amount of time */
 745                 extra_time += cfs_time_current_sec() -
 746                         req->rq_arrival_time.tv_sec;
 747                 at_add(&svc->srv_at_estimate, extra_time);
 748         }
 749
 750         newdl = req->rq_arrival_time.tv_sec + at_get(&svc->srv_at_estimate);
 751         if (req->rq_deadline >= newdl) {
 752                 /* We're not adding any time, no need to send an early reply
 753                    (e.g. maybe at adaptive_max) */
 754                 DEBUG_REQ(D_WARNING, req, "Couldn't add any time ("
 755                           CFS_DURATION_T"/"CFS_DURATION_T"), "
 756                           "not sending early reply\n", olddl,
 757                           cfs_time_sub(newdl, cfs_time_current_sec()));
 758                 RETURN(-ETIMEDOUT);
 759         }
 760
 761         OBD_ALLOC(reqcopy, sizeof *reqcopy);
 762         if (reqcopy == NULL)
 763                 RETURN(-ENOMEM);
 764         OBD_ALLOC(reqmsg, req->rq_reqlen);
 765         if (!reqmsg) {
 766                 OBD_FREE(reqcopy, sizeof *reqcopy);
 767                 RETURN(-ENOMEM);
 768         }
 769
 770         *reqcopy = *req;
 771         reqcopy->rq_reply_state = NULL;
 772         reqcopy->rq_rep_swab_mask = 0;
 773         reqcopy->rq_pack_bulk = 0;
 774         reqcopy->rq_pack_udesc = 0;
 775         reqcopy->rq_packed_final = 0;
 776         sptlrpc_svc_ctx_addref(reqcopy);
 777         /* We only need the reqmsg for the magic */
 778         reqcopy->rq_reqmsg = reqmsg;
 779         memcpy(reqmsg, req->rq_reqmsg, req->rq_reqlen);
 780
 781         if (req->rq_sent_final) {
 782                 DEBUG_REQ(D_ADAPTTO, reqcopy, "Normal reply already sent out, "
 783                           "abort sending early reply\n");
 784                 GOTO(out, rc = 0);
 785         }
 786
 787         /* Connection ref */
 788         reqcopy->rq_export = class_conn2export(
 789                                      lustre_msg_get_handle(reqcopy->rq_reqmsg));
 790         if (reqcopy->rq_export == NULL)
 791                 GOTO(out, rc = -ENODEV);
 792
 793         /* RPC ref */
 794         class_export_rpc_get(reqcopy->rq_export);
 795         if (reqcopy->rq_export->exp_obd &&
 796             reqcopy->rq_export->exp_obd->obd_fail)
 797                 GOTO(out_put, rc = -ENODEV);
 798
 799         rc = lustre_pack_reply_flags(reqcopy, 1, NULL, NULL, LPRFL_EARLY_REPLY);
 800         if (rc)
 801                 GOTO(out_put, rc);
 802
 803         rc = ptlrpc_send_reply(reqcopy, PTLRPC_REPLY_EARLY);
 804
 805         if (!rc) {
 806                 /* Adjust our own deadline to what we told the client */
 807                 req->rq_deadline = newdl;
 808                 req->rq_early_count++; /* number sent, server side */
 809         } else {
 810                 DEBUG_REQ(D_ERROR, req, "Early reply send failed %d", rc);
 811         }
 812
 813         /* Free the (early) reply state from lustre_pack_reply.
 814            (ptlrpc_send_reply takes it's own rs ref, so this is safe here) */
 815         ptlrpc_req_drop_rs(reqcopy);
 816
 817 out_put:
 818         class_export_rpc_put(reqcopy->rq_export);
 819         class_export_put(reqcopy->rq_export);
 820 out:
 821         sptlrpc_svc_ctx_decref(reqcopy);
 822         OBD_FREE(reqmsg, req->rq_reqlen);
 823         OBD_FREE(reqcopy, sizeof *reqcopy);
 824         RETURN(rc);
 825 }
 826
 827 /* Send early replies to everybody expiring within at_early_margin
 828    asking for at_extra time */
 829 static int ptlrpc_at_check_timed(struct ptlrpc_service *svc)
 830 {
 831         struct ptlrpc_request *rq, *n;
 832         struct list_head work_list;
 833         time_t now = cfs_time_current_sec();
 834         cfs_duration_t delay;
 835         int first, counter = 0;
 836         ENTRY;
 837
 838         spin_lock(&svc->srv_at_lock);
 839         if (svc->srv_at_check == 0) {
 840                 spin_unlock(&svc->srv_at_lock);
 841                 RETURN(0);
 842         }
 843         delay = cfs_time_sub(cfs_time_current(), svc->srv_at_checktime);
 844         svc->srv_at_check = 0;
 845
 846         if (list_empty(&svc->srv_at_list)) {
 847                 spin_unlock(&svc->srv_at_lock);
 848                 RETURN(0);
 849         }
 850
 851         /* The timer went off, but maybe the nearest rpc already completed. */
 852         rq = list_entry(svc->srv_at_list.next, struct ptlrpc_request,
 853                         rq_timed_list);
 854         first = (int)(rq->rq_deadline - now);
 855         if (first > at_early_margin) {
 856                 /* We've still got plenty of time.  Reset the timer. */
 857                 spin_unlock(&svc->srv_at_lock);
 858                 ptlrpc_at_set_timer(svc);
 859                 RETURN(0);
 860         }
 861
 862         /* We're close to a timeout, and we don't know how much longer the
 863            server will take. Send early replies to everyone expiring soon. */
 864         CFS_INIT_LIST_HEAD(&work_list);
 865         list_for_each_entry_safe(rq, n, &svc->srv_at_list, rq_timed_list) {
 866                 if (rq->rq_deadline <= now + at_early_margin) {
 867                         list_move_tail(&rq->rq_timed_list, &work_list);
 868                         counter++;
 869                 } else {
 870                         break;
 871                 }
 872         }
 873
 874         spin_unlock(&svc->srv_at_lock);
 875
 876         /* we have a new earliest deadline, restart the timer */
 877         ptlrpc_at_set_timer(svc);
 878
 879         CDEBUG(D_ADAPTTO, "timeout in %+ds, asking for %d secs on %d early "
 880                "replies\n", first, at_extra, counter);
 881         if (first < 0) {
 882                 /* We're already past request deadlines before we even get a
 883                    chance to send early replies */
 884                 LCONSOLE_WARN("%s: This server is not able to keep up with "
 885                               "request traffic (cpu-bound).\n", svc->srv_name);
 886                 CWARN("earlyQ=%d reqQ=%d recA=%d, svcEst=%d, "
 887                       "delay="CFS_DURATION_T"(jiff)\n",
 888                       counter, svc->srv_n_queued_reqs, svc->srv_n_active_reqs,
 889                       at_get(&svc->srv_at_estimate), delay);
 890         }
 891
 892         /* ptlrpc_server_free_request may delete an entry out of the work
 893            list */
 894         spin_lock(&svc->srv_at_lock);
 895         while (!list_empty(&work_list)) {
 896                 rq = list_entry(work_list.next, struct ptlrpc_request,
 897                                 rq_timed_list);
 898                 list_del_init(&rq->rq_timed_list);
 899                 /* if the entry is still in the worklist, it hasn't been
 900                    deleted, and is safe to take a ref to keep the req around */
 901                 atomic_inc(&rq->rq_refcount);
 902                 spin_unlock(&svc->srv_at_lock);
 903
 904                 if (ptlrpc_at_send_early_reply(rq, at_extra) == 0)
 905                         ptlrpc_at_add_timed(rq);
 906
 907                 ptlrpc_server_req_decref(rq);
 908                 spin_lock(&svc->srv_at_lock);
 909         }
 910         spin_unlock(&svc->srv_at_lock);
 911
 912         RETURN(0);
 913 }
 914
 915 /* Handle freshly incoming reqs, add to timed early reply list,
 916    pass on to regular request queue */
 917 static int
 918 ptlrpc_server_handle_req_in(struct ptlrpc_service *svc)
 919 {
 920         struct ptlrpc_request *req;
 921         __u32                  deadline;
 922         int                    rc;
 923         ENTRY;
 924
 925         LASSERT(svc);
 926
 927         spin_lock(&svc->srv_lock);
 928         if (list_empty(&svc->srv_req_in_queue)) {
 929                 spin_unlock(&svc->srv_lock);
 930                 RETURN(0);
 931         }
 932
 933         req = list_entry(svc->srv_req_in_queue.next,
 934                          struct ptlrpc_request, rq_list);
 935         list_del_init (&req->rq_list);
 936         /* Consider this still a "queued" request as far as stats are
 937            concerned */
 938         spin_unlock(&svc->srv_lock);
 939
 940         /* go through security check/transform */
 941         rc = sptlrpc_svc_unwrap_request(req);
 942         switch (rc) {
 943         case SECSVC_OK:
 944                 break;
 945         case SECSVC_COMPLETE:
 946                 target_send_reply(req, 0, OBD_FAIL_MDS_ALL_REPLY_NET);
 947                 goto err_req;
 948         case SECSVC_DROP:
 949                 goto err_req;
 950         default:
 951                 LBUG();
 952         }
 953
 954         /* Clear request swab mask; this is a new request */
 955         req->rq_req_swab_mask = 0;
 956
 957         rc = lustre_unpack_msg(req->rq_reqmsg, req->rq_reqlen);
 958         if (rc != 0) {
 959                 CERROR("error unpacking request: ptl %d from %s x"LPU64"\n",
 960                        svc->srv_req_portal, libcfs_id2str(req->rq_peer),
 961                        req->rq_xid);
 962                 goto err_req;
 963         }
 964
 965         rc = lustre_unpack_req_ptlrpc_body(req, MSG_PTLRPC_BODY_OFF);
 966         if (rc) {
 967                 CERROR ("error unpacking ptlrpc body: ptl %d from %s x"
 968                         LPU64"\n", svc->srv_req_portal,
 969                         libcfs_id2str(req->rq_peer), req->rq_xid);
 970                 goto err_req;
 971         }
 972
 973         rc = -EINVAL;
 974         if (lustre_msg_get_type(req->rq_reqmsg) != PTL_RPC_MSG_REQUEST) {
 975                 CERROR("wrong packet type received (type=%u) from %s\n",
 976                        lustre_msg_get_type(req->rq_reqmsg),
 977                        libcfs_id2str(req->rq_peer));
 978                 goto err_req;
 979         }
 980
 981         CDEBUG(D_NET, "got req "LPD64"\n", req->rq_xid);
 982
 983         req->rq_export = class_conn2export(
 984                 lustre_msg_get_handle(req->rq_reqmsg));
 985         if (req->rq_export) {
 986                 rc = ptlrpc_check_req(req);
 987                 if (rc == 0) {
 988                         rc = sptlrpc_target_export_check(req->rq_export, req);
 989                         if (rc)
 990                                 DEBUG_REQ(D_ERROR, req, "DROPPING req with "
 991                                           "illegal security flavor,");
 992                 }
 993
 994                 class_export_put(req->rq_export);
 995                 req->rq_export = NULL;
 996                 if (rc)
 997                         goto err_req;
 998         }
 999
1000         /* req_in handling should/must be fast */
1001         if (cfs_time_current_sec() - req->rq_arrival_time.tv_sec > 5)
1002                 DEBUG_REQ(D_WARNING, req, "Slow req_in handling "CFS_DURATION_T"s",
1003                           cfs_time_sub(cfs_time_current_sec(),
1004                                        req->rq_arrival_time.tv_sec));
1005
1006         /* Set rpc server deadline and add it to the timed list */
1007         deadline = (lustre_msghdr_get_flags(req->rq_reqmsg) &
1008                     MSGHDR_AT_SUPPORT) ?
1009                    /* The max time the client expects us to take */
1010                    lustre_msg_get_timeout(req->rq_reqmsg) : obd_timeout;
1011         req->rq_deadline = req->rq_arrival_time.tv_sec + deadline;
1012         if (unlikely(deadline == 0)) {
1013                 DEBUG_REQ(D_ERROR, req, "Dropping request with 0 timeout");
1014                 goto err_req;
1015         }
1016
1017         ptlrpc_at_add_timed(req);
1018
1019         /* Move it over to the request processing queue */
1020         spin_lock(&svc->srv_lock);
1021         list_add_tail(&req->rq_list, &svc->srv_request_queue);
1022         cfs_waitq_signal(&svc->srv_waitq);
1023         spin_unlock(&svc->srv_lock);
1024         RETURN(1);
1025
1026 err_req:
1027         spin_lock(&svc->srv_lock);
1028         svc->srv_n_queued_reqs--;
1029         svc->srv_n_active_reqs++;
1030         spin_unlock(&svc->srv_lock);
1031         ptlrpc_server_free_request(req);
1032
1033         RETURN(1);
1034 }
1035
1036 static int
1037 ptlrpc_server_handle_request(struct ptlrpc_service *svc,
1038                              struct ptlrpc_thread *thread)
1039 {
1040         struct obd_export     *export = NULL;
1041         struct ptlrpc_request *request;
1042         struct timeval         work_start;
1043         struct timeval         work_end;
1044         long                   timediff;
1045         int                    rc;
1046         ENTRY;
1047
1048         LASSERT(svc);
1049
1050         spin_lock(&svc->srv_lock);
1051         if (unlikely(list_empty (&svc->srv_request_queue) ||
1052             (
1053 #ifndef __KERNEL__
1054              /* !@%$# liblustre only has 1 thread */
1055              svc->srv_n_difficult_replies != 0 &&
1056 #endif
1057              svc->srv_n_active_reqs >= (svc->srv_threads_running - 1)))) {
1058                  /* Don't handle regular requests in the last thread, in order               * re
1059                   * to handle difficult replies (which might block other threads)
1060                   * as well as handle any incoming reqs, early replies, etc.
1061                   * That means we always need at least 2 service threads. */
1062                 spin_unlock(&svc->srv_lock);
1063                 RETURN(0);
1064         }
1065
1066         request = list_entry (svc->srv_request_queue.next,
1067                               struct ptlrpc_request, rq_list);
1068         list_del_init (&request->rq_list);
1069         svc->srv_n_queued_reqs--;
1070         svc->srv_n_active_reqs++;
1071
1072         spin_unlock(&svc->srv_lock);
1073
1074         if(OBD_FAIL_CHECK(OBD_FAIL_PTLRPC_DUMP_LOG))
1075                 libcfs_debug_dumplog();
1076
1077         do_gettimeofday(&work_start);
1078         timediff = cfs_timeval_sub(&work_start, &request->rq_arrival_time,NULL);
1079         if (likely(svc->srv_stats != NULL)) {
1080                 lprocfs_counter_add(svc->srv_stats, PTLRPC_REQWAIT_CNTR,
1081                                     timediff);
1082                 lprocfs_counter_add(svc->srv_stats, PTLRPC_REQQDEPTH_CNTR,
1083                                     svc->srv_n_queued_reqs);
1084                 lprocfs_counter_add(svc->srv_stats, PTLRPC_REQACTIVE_CNTR,
1085                                     svc->srv_n_active_reqs);
1086                 lprocfs_counter_add(svc->srv_stats, PTLRPC_TIMEOUT,
1087                                     at_get(&svc->srv_at_estimate));
1088         }
1089
1090         rc = lu_context_init(&request->rq_session, LCT_SESSION);
1091         if (rc) {
1092                 CERROR("Failure to initialize session: %d\n", rc);
1093                 goto out_req;
1094         }
1095         request->rq_session.lc_thread = thread;
1096         lu_context_enter(&request->rq_session);
1097
1098         CDEBUG(D_NET, "got req "LPD64"\n", request->rq_xid);
1099
1100         request->rq_svc_thread = thread;
1101         if (thread)
1102                 request->rq_svc_thread->t_env->le_ses = &request->rq_session;
1103
1104         request->rq_export = class_conn2export(
1105                                      lustre_msg_get_handle(request->rq_reqmsg));
1106
1107         if (likely(request->rq_export)) {
1108                 if (unlikely(ptlrpc_check_req(request)))
1109                         goto put_conn;
1110                 ptlrpc_update_export_timer(request->rq_export, timediff >> 19);
1111                 export = class_export_rpc_get(request->rq_export);
1112         }
1113
1114         /* Discard requests queued for longer than the deadline.
1115            The deadline is increased if we send an early reply. */
1116         if (cfs_time_current_sec() > request->rq_deadline) {
1117                 DEBUG_REQ(D_ERROR, request, "Dropping timed-out request from %s"
1118                           ": deadline "CFS_DURATION_T":"CFS_DURATION_T"s ago\n",
1119                           libcfs_id2str(request->rq_peer),
1120                           cfs_time_sub(request->rq_deadline,
1121                           request->rq_arrival_time.tv_sec),
1122                           cfs_time_sub(cfs_time_current_sec(),
1123                           request->rq_deadline));
1124                 goto put_rpc_export;
1125         }
1126
1127         request->rq_phase = RQ_PHASE_INTERPRET;
1128
1129         CDEBUG(D_RPCTRACE, "Handling RPC pname:cluuid+ref:pid:xid:nid:opc "
1130                "%s:%s+%d:%d:x"LPU64":%s:%d\n", cfs_curproc_comm(),
1131                (request->rq_export ?
1132                 (char *)request->rq_export->exp_client_uuid.uuid : "0"),
1133                (request->rq_export ?
1134                 atomic_read(&request->rq_export->exp_refcount) : -99),
1135                lustre_msg_get_status(request->rq_reqmsg), request->rq_xid,
1136                libcfs_id2str(request->rq_peer),
1137                lustre_msg_get_opc(request->rq_reqmsg));
1138
1139         OBD_FAIL_TIMEOUT_MS(OBD_FAIL_PTLRPC_PAUSE_REQ, obd_fail_val);
1140
1141         rc = svc->srv_handler(request);
1142
1143         request->rq_phase = RQ_PHASE_COMPLETE;
1144
1145         CDEBUG(D_RPCTRACE, "Handled RPC pname:cluuid+ref:pid:xid:nid:opc "
1146                "%s:%s+%d:%d:x"LPU64":%s:%d\n", cfs_curproc_comm(),
1147                (request->rq_export ?
1148                 (char *)request->rq_export->exp_client_uuid.uuid : "0"),
1149                (request->rq_export ?
1150                 atomic_read(&request->rq_export->exp_refcount) : -99),
1151                lustre_msg_get_status(request->rq_reqmsg), request->rq_xid,
1152                libcfs_id2str(request->rq_peer),
1153                lustre_msg_get_opc(request->rq_reqmsg));
1154
1155 put_rpc_export:
1156         if (export != NULL)
1157                 class_export_rpc_put(export);
1158 put_conn:
1159         if (likely(request->rq_export != NULL))
1160                 class_export_put(request->rq_export);
1161
1162         lu_context_exit(&request->rq_session);
1163         lu_context_fini(&request->rq_session);
1164
1165         if (unlikely(cfs_time_current_sec() > request->rq_deadline)) {
1166                 DEBUG_REQ(D_WARNING, request, "Request x"LPU64" took longer "
1167                           "than estimated ("CFS_DURATION_T":"CFS_DURATION_T"s);"
1168                           " client may timeout.",
1169                           request->rq_xid, cfs_time_sub(request->rq_deadline,
1170                           request->rq_arrival_time.tv_sec),
1171                           cfs_time_sub(cfs_time_current_sec(),
1172                           request->rq_deadline));
1173         }
1174
1175         do_gettimeofday(&work_end);
1176         timediff = cfs_timeval_sub(&work_end, &work_start, NULL);
1177         CDEBUG(D_RPCTRACE, "request x"LPU64" opc %u from %s processed in "
1178                "%ldus (%ldus total) trans "LPU64" rc %d/%d\n",
1179                request->rq_xid, lustre_msg_get_opc(request->rq_reqmsg),
1180                libcfs_id2str(request->rq_peer), timediff,
1181                cfs_timeval_sub(&work_end, &request->rq_arrival_time, NULL),
1182                request->rq_repmsg ? lustre_msg_get_transno(request->rq_repmsg) :
1183                request->rq_transno, request->rq_status,
1184                request->rq_repmsg ? lustre_msg_get_status(request->rq_repmsg):
1185                -999);
1186         if (likely(svc->srv_stats != NULL && request->rq_reqmsg != NULL)) {
1187                 __u32 op = lustre_msg_get_opc(request->rq_reqmsg);
1188                 int opc = opcode_offset(op);
1189                 if (opc > 0 && !(op == LDLM_ENQUEUE || op == MDS_REINT)) {
1190                         LASSERT(opc < LUSTRE_MAX_OPCODES);
1191                         lprocfs_counter_add(svc->srv_stats,
1192                                             opc + EXTRA_MAX_OPCODES,
1193                                             timediff);
1194                 }
1195         }
1196         if (unlikely(request->rq_early_count)) {
1197                 DEBUG_REQ(D_ADAPTTO, request,
1198                           "sent %d early replies before finishing in "
1199                           CFS_DURATION_T"s",
1200                           request->rq_early_count,
1201                           cfs_time_sub(work_end.tv_sec,
1202                           request->rq_arrival_time.tv_sec));
1203         }
1204
1205 out_req:
1206         ptlrpc_server_free_request(request);
1207
1208         RETURN(1);
1209 }
1210
1211 static int
1212 ptlrpc_server_handle_reply (struct ptlrpc_service *svc)
1213 {
1214         struct ptlrpc_reply_state *rs;
1215         struct obd_export         *exp;
1216         struct obd_device         *obd;
1217         int                        nlocks;
1218         int                        been_handled;
1219         ENTRY;
1220
1221         spin_lock(&svc->srv_lock);
1222         if (list_empty (&svc->srv_reply_queue)) {
1223                 spin_unlock(&svc->srv_lock);
1224                 RETURN(0);
1225         }
1226
1227         rs = list_entry (svc->srv_reply_queue.next,
1228                          struct ptlrpc_reply_state, rs_list);
1229
1230         exp = rs->rs_export;
1231         obd = exp->exp_obd;
1232
1233         LASSERT (rs->rs_difficult);
1234         LASSERT (rs->rs_scheduled);
1235
1236         list_del_init (&rs->rs_list);
1237
1238         /* Disengage from notifiers carefully (lock order - irqrestore below!)*/
1239         spin_unlock(&svc->srv_lock);
1240
1241         spin_lock (&obd->obd_uncommitted_replies_lock);
1242         /* Noop if removed already */
1243         list_del_init (&rs->rs_obd_list);
1244         spin_unlock (&obd->obd_uncommitted_replies_lock);
1245
1246         spin_lock (&exp->exp_lock);
1247         /* Noop if removed already */
1248         list_del_init (&rs->rs_exp_list);
1249         spin_unlock (&exp->exp_lock);
1250
1251         spin_lock(&svc->srv_lock);
1252
1253         been_handled = rs->rs_handled;
1254         rs->rs_handled = 1;
1255
1256         nlocks = rs->rs_nlocks;                 /* atomic "steal", but */
1257         rs->rs_nlocks = 0;                      /* locks still on rs_locks! */
1258
1259         if (nlocks == 0 && !been_handled) {
1260                 /* If we see this, we should already have seen the warning
1261                  * in mds_steal_ack_locks()  */
1262                 CWARN("All locks stolen from rs %p x"LPD64".t"LPD64
1263                       " o%d NID %s\n",
1264                       rs,
1265                       rs->rs_xid, rs->rs_transno,
1266                       lustre_msg_get_opc(rs->rs_msg),
1267                       libcfs_nid2str(exp->exp_connection->c_peer.nid));
1268         }
1269
1270         if ((!been_handled && rs->rs_on_net) || nlocks > 0) {
1271                 spin_unlock(&svc->srv_lock);
1272
1273                 if (!been_handled && rs->rs_on_net) {
1274                         LNetMDUnlink(rs->rs_md_h);
1275                         /* Ignore return code; we're racing with
1276                          * completion... */
1277                 }
1278
1279                 while (nlocks-- > 0)
1280                         ldlm_lock_decref(&rs->rs_locks[nlocks],
1281                                          rs->rs_modes[nlocks]);
1282
1283                 spin_lock(&svc->srv_lock);
1284         }
1285
1286         rs->rs_scheduled = 0;
1287
1288         if (!rs->rs_on_net) {
1289                 /* Off the net */
1290                 svc->srv_n_difficult_replies--;
1291                 spin_unlock(&svc->srv_lock);
1292
1293                 class_export_put (exp);
1294                 rs->rs_export = NULL;
1295                 ptlrpc_rs_decref (rs);
1296                 atomic_dec (&svc->srv_outstanding_replies);
1297                 RETURN(1);
1298         }
1299
1300         /* still on the net; callback will schedule */
1301         spin_unlock(&svc->srv_lock);
1302         RETURN(1);
1303 }
1304
1305 #ifndef __KERNEL__
1306 /* FIXME make use of timeout later */
1307 int
1308 liblustre_check_services (void *arg)
1309 {
1310         int  did_something = 0;
1311         int  rc;
1312         struct list_head *tmp, *nxt;
1313         ENTRY;
1314
1315         /* I'm relying on being single threaded, not to have to lock
1316          * ptlrpc_all_services etc */
1317         list_for_each_safe (tmp, nxt, &ptlrpc_all_services) {
1318                 struct ptlrpc_service *svc =
1319                         list_entry (tmp, struct ptlrpc_service, srv_list);
1320
1321                 if (svc->srv_threads_running != 0)     /* I've recursed */
1322                         continue;
1323
1324                 /* service threads can block for bulk, so this limits us
1325                  * (arbitrarily) to recursing 1 stack frame per service.
1326                  * Note that the problem with recursion is that we have to
1327                  * unwind completely before our caller can resume. */
1328
1329                 svc->srv_threads_running++;
1330
1331                 do {
1332                         rc = ptlrpc_server_handle_req_in(svc);
1333                         rc |= ptlrpc_server_handle_reply(svc);
1334                         rc |= ptlrpc_at_check_timed(svc);
1335                         rc |= ptlrpc_server_handle_request(svc, NULL);
1336                         rc |= (ptlrpc_server_post_idle_rqbds(svc) > 0);
1337                         did_something |= rc;
1338                 } while (rc);
1339
1340                 svc->srv_threads_running--;
1341         }
1342
1343         RETURN(did_something);
1344 }
1345 #define ptlrpc_stop_all_threads(s) do {} while (0)
1346
1347 #else /* __KERNEL__ */
1348
1349 /* Don't use daemonize, it removes fs struct from new thread (bug 418) */
1350 void ptlrpc_daemonize(char *name)
1351 {
1352         struct fs_struct *fs = current->fs;
1353
1354         atomic_inc(&fs->count);
1355         cfs_daemonize(name);
1356         exit_fs(cfs_current());
1357         current->fs = fs;
1358         ll_set_fs_pwd(current->fs, init_task.fs->pwdmnt, init_task.fs->pwd);
1359 }
1360
1361 static void
1362 ptlrpc_check_rqbd_pool(struct ptlrpc_service *svc)
1363 {
1364         int avail = svc->srv_nrqbd_receiving;
1365         int low_water = test_req_buffer_pressure ? 0 :
1366                         svc->srv_nbuf_per_group/2;
1367
1368         /* NB I'm not locking; just looking. */
1369
1370         /* CAVEAT EMPTOR: We might be allocating buffers here because we've
1371          * allowed the request history to grow out of control.  We could put a
1372          * sanity check on that here and cull some history if we need the
1373          * space. */
1374
1375         if (avail <= low_water)
1376                 ptlrpc_grow_req_bufs(svc);
1377
1378         if (svc->srv_stats)
1379                 lprocfs_counter_add(svc->srv_stats, PTLRPC_REQBUF_AVAIL_CNTR,
1380                                     avail);
1381 }
1382
1383 static int
1384 ptlrpc_retry_rqbds(void *arg)
1385 {
1386         struct ptlrpc_service *svc = (struct ptlrpc_service *)arg;
1387
1388         svc->srv_rqbd_timeout = 0;
1389         return (-ETIMEDOUT);
1390 }
1391
1392 static int ptlrpc_main(void *arg)
1393 {
1394         struct ptlrpc_svc_data *data = (struct ptlrpc_svc_data *)arg;
1395         struct ptlrpc_service  *svc = data->svc;
1396         struct ptlrpc_thread   *thread = data->thread;
1397         struct obd_device      *dev = data->dev;
1398         struct ptlrpc_reply_state *rs;
1399         struct lc_watchdog     *watchdog;
1400 #ifdef WITH_GROUP_INFO
1401         struct group_info *ginfo = NULL;
1402 #endif
1403         struct lu_env env;
1404         int counter = 0, rc = 0;
1405         ENTRY;
1406
1407         ptlrpc_daemonize(data->name);
1408
1409 #if defined(HAVE_NODE_TO_CPUMASK) && defined(CONFIG_NUMA)
1410         /* we need to do this before any per-thread allocation is done so that
1411          * we get the per-thread allocations on local node.  bug 7342 */
1412         if (svc->srv_cpu_affinity) {
1413                 int cpu, num_cpu;
1414
1415                 for (cpu = 0, num_cpu = 0; cpu < num_possible_cpus(); cpu++) {
1416                         if (!cpu_online(cpu))
1417                                 continue;
1418                         if (num_cpu == thread->t_id % num_online_cpus())
1419                                 break;
1420                         num_cpu++;
1421                 }
1422                 set_cpus_allowed(cfs_current(), node_to_cpumask(cpu_to_node(cpu)));
1423         }
1424 #endif
1425
1426 #ifdef WITH_GROUP_INFO
1427         ginfo = groups_alloc(0);
1428         if (!ginfo) {
1429                 rc = -ENOMEM;
1430                 goto out;
1431         }
1432
1433         set_current_groups(ginfo);
1434         put_group_info(ginfo);
1435 #endif
1436
1437         if (svc->srv_init != NULL) {
1438                 rc = svc->srv_init(thread);
1439                 if (rc)
1440                         goto out;
1441         }
1442
1443         rc = lu_context_init(&env.le_ctx, svc->srv_ctx_tags);
1444         if (rc)
1445                 goto out_srv_fini;
1446
1447         thread->t_env = &env;
1448         env.le_ctx.lc_thread = thread;
1449
1450         /* Alloc reply state structure for this one */
1451         OBD_ALLOC_GFP(rs, svc->srv_max_reply_size, CFS_ALLOC_STD);
1452         if (!rs) {
1453                 rc = -ENOMEM;
1454                 goto out_srv_fini;
1455         }
1456
1457         /* Record that the thread is running */
1458         thread->t_flags = SVC_RUNNING;
1459         /*
1460          * wake up our creator. Note: @data is invalid after this point,
1461          * because it's allocated on ptlrpc_start_thread() stack.
1462          */
1463         cfs_waitq_signal(&thread->t_ctl_waitq);
1464
1465         watchdog = lc_watchdog_add(max_t(int, obd_timeout, AT_OFF ? 0 :
1466                                    at_get(&svc->srv_at_estimate)) *
1467                                    svc->srv_watchdog_factor, NULL, NULL);
1468
1469         spin_lock(&svc->srv_lock);
1470         svc->srv_threads_running++;
1471         list_add(&rs->rs_list, &svc->srv_free_rs_list);
1472         spin_unlock(&svc->srv_lock);
1473         cfs_waitq_signal(&svc->srv_free_rs_waitq);
1474
1475         CDEBUG(D_NET, "service thread %d (#%d)started\n", thread->t_id,
1476               svc->srv_threads_running);
1477
1478         /* XXX maintain a list of all managed devices: insert here */
1479
1480         while ((thread->t_flags & SVC_STOPPING) == 0 ||
1481                svc->srv_n_difficult_replies != 0) {
1482                 /* Don't exit while there are replies to be handled */
1483                 struct l_wait_info lwi = LWI_TIMEOUT(svc->srv_rqbd_timeout,
1484                                                      ptlrpc_retry_rqbds, svc);
1485
1486                 lc_watchdog_disable(watchdog);
1487
1488                 cond_resched();
1489
1490                 l_wait_event_exclusive (svc->srv_waitq,
1491                               ((thread->t_flags & SVC_STOPPING) != 0 &&
1492                                svc->srv_n_difficult_replies == 0) ||
1493                               (!list_empty(&svc->srv_idle_rqbds) &&
1494                                svc->srv_rqbd_timeout == 0) ||
1495                               !list_empty(&svc->srv_req_in_queue) ||
1496                               !list_empty(&svc->srv_reply_queue) ||
1497                               (!list_empty(&svc->srv_request_queue) &&
1498                                (svc->srv_n_active_reqs <
1499                                 (svc->srv_threads_running - 1))) ||
1500                               svc->srv_at_check,
1501                               &lwi);
1502
1503                 lc_watchdog_touch_ms(watchdog, max_t(int, obd_timeout,
1504                                      AT_OFF ? 0 :
1505                                      at_get(&svc->srv_at_estimate)) *
1506                                      svc->srv_watchdog_factor);
1507
1508                 ptlrpc_check_rqbd_pool(svc);
1509
1510                 if ((svc->srv_threads_started < svc->srv_threads_max) &&
1511                     (svc->srv_n_active_reqs >= (svc->srv_threads_started - 1))){
1512                         /* Ignore return code - we tried... */
1513                         ptlrpc_start_thread(dev, svc);
1514                 }
1515
1516                 if (!list_empty(&svc->srv_reply_queue))
1517                         ptlrpc_server_handle_reply(svc);
1518
1519                 if (!list_empty(&svc->srv_req_in_queue)) {
1520                         /* Process all incoming reqs before handling any */
1521                         ptlrpc_server_handle_req_in(svc);
1522                         /* but limit ourselves in case of flood */
1523                         if (counter++ < 1000)
1524                                 continue;
1525                         counter = 0;
1526                 }
1527
1528                 if (svc->srv_at_check)
1529                         ptlrpc_at_check_timed(svc);
1530
1531                 /* don't handle requests in the last thread */
1532                 if (!list_empty (&svc->srv_request_queue) &&
1533                     (svc->srv_n_active_reqs < (svc->srv_threads_running - 1))) {
1534                         lu_context_enter(&env.le_ctx);
1535                         ptlrpc_server_handle_request(svc, thread);
1536                         lu_context_exit(&env.le_ctx);
1537                 }
1538
1539                 if (!list_empty(&svc->srv_idle_rqbds) &&
1540                     ptlrpc_server_post_idle_rqbds(svc) < 0) {
1541                         /* I just failed to repost request buffers.  Wait
1542                          * for a timeout (unless something else happens)
1543                          * before I try again */
1544                         svc->srv_rqbd_timeout = cfs_time_seconds(1)/10;
1545                         CDEBUG(D_RPCTRACE,"Posted buffers: %d\n",
1546                                svc->srv_nrqbd_receiving);
1547                 }
1548         }
1549
1550         lc_watchdog_delete(watchdog);
1551
1552 out_srv_fini:
1553         /*
1554          * deconstruct service specific state created by ptlrpc_start_thread()
1555          */
1556         if (svc->srv_done != NULL)
1557                 svc->srv_done(thread);
1558
1559         lu_context_fini(&env.le_ctx);
1560 out:
1561         CDEBUG(D_NET, "service thread %d exiting: rc %d\n", thread->t_id, rc);
1562
1563         spin_lock(&svc->srv_lock);
1564         svc->srv_threads_running--; /* must know immediately */
1565         thread->t_id = rc;
1566         thread->t_flags = SVC_STOPPED;
1567
1568         cfs_waitq_signal(&thread->t_ctl_waitq);
1569         spin_unlock(&svc->srv_lock);
1570
1571         return rc;
1572 }
1573
1574 static void ptlrpc_stop_thread(struct ptlrpc_service *svc,
1575                                struct ptlrpc_thread *thread)
1576 {
1577         struct l_wait_info lwi = { 0 };
1578
1579         spin_lock(&svc->srv_lock);
1580         thread->t_flags = SVC_STOPPING;
1581         spin_unlock(&svc->srv_lock);
1582
1583         cfs_waitq_broadcast(&svc->srv_waitq);
1584         l_wait_event(thread->t_ctl_waitq, (thread->t_flags & SVC_STOPPED),
1585                      &lwi);
1586
1587         spin_lock(&svc->srv_lock);
1588         list_del(&thread->t_link);
1589         spin_unlock(&svc->srv_lock);
1590
1591         OBD_FREE_PTR(thread);
1592 }
1593
1594 void ptlrpc_stop_all_threads(struct ptlrpc_service *svc)
1595 {
1596         struct ptlrpc_thread *thread;
1597
1598         spin_lock(&svc->srv_lock);
1599         while (!list_empty(&svc->srv_threads)) {
1600                 thread = list_entry(svc->srv_threads.next,
1601                                     struct ptlrpc_thread, t_link);
1602
1603                 spin_unlock(&svc->srv_lock);
1604                 ptlrpc_stop_thread(svc, thread);
1605                 spin_lock(&svc->srv_lock);
1606         }
1607
1608         spin_unlock(&svc->srv_lock);
1609 }
1610
1611 int ptlrpc_start_threads(struct obd_device *dev, struct ptlrpc_service *svc)
1612 {
1613         int i, rc = 0;
1614         ENTRY;
1615
1616         /* We require 2 threads min - see note in
1617            ptlrpc_server_handle_request */
1618         LASSERT(svc->srv_threads_min >= 2);
1619         for (i = 0; i < svc->srv_threads_min; i++) {
1620                 rc = ptlrpc_start_thread(dev, svc);
1621                 /* We have enough threads, don't start more.  b=15759 */
1622                 if (rc == -EMFILE)
1623                         break;
1624                 if (rc) {
1625                         CERROR("cannot start %s thread #%d: rc %d\n",
1626                                svc->srv_thread_name, i, rc);
1627                         ptlrpc_stop_all_threads(svc);
1628                 }
1629         }
1630         RETURN(rc);
1631 }
1632
1633 int ptlrpc_start_thread(struct obd_device *dev, struct ptlrpc_service *svc)
1634 {
1635         struct l_wait_info lwi = { 0 };
1636         struct ptlrpc_svc_data d;
1637         struct ptlrpc_thread *thread;
1638         char name[32];
1639         int id, rc;
1640         ENTRY;
1641
1642         CDEBUG(D_RPCTRACE, "%s started %d min %d max %d running %d\n",
1643                svc->srv_name, svc->srv_threads_started, svc->srv_threads_min,
1644                svc->srv_threads_max, svc->srv_threads_running);
1645         if (unlikely(svc->srv_threads_started >= svc->srv_threads_max) ||
1646             (OBD_FAIL_CHECK(OBD_FAIL_TGT_TOOMANY_THREADS) &&
1647              svc->srv_threads_started == svc->srv_threads_min - 1))
1648                 RETURN(-EMFILE);
1649
1650         OBD_ALLOC_PTR(thread);
1651         if (thread == NULL)
1652                 RETURN(-ENOMEM);
1653         cfs_waitq_init(&thread->t_ctl_waitq);
1654
1655         spin_lock(&svc->srv_lock);
1656         if (svc->srv_threads_started >= svc->srv_threads_max) {
1657                 spin_unlock(&svc->srv_lock);
1658                 OBD_FREE_PTR(thread);
1659                 RETURN(-EMFILE);
1660         }
1661         list_add(&thread->t_link, &svc->srv_threads);
1662         id = svc->srv_threads_started++;
1663         spin_unlock(&svc->srv_lock);
1664
1665         thread->t_id = id;
1666         sprintf(name, "%s_%02d", svc->srv_thread_name, id);
1667         d.dev = dev;
1668         d.svc = svc;
1669         d.name = name;
1670         d.thread = thread;
1671
1672         CDEBUG(D_RPCTRACE, "starting thread '%s'\n", name);
1673
1674           /* CLONE_VM and CLONE_FILES just avoid a needless copy, because we
1675          * just drop the VM and FILES in ptlrpc_daemonize() right away.
1676          */
1677         rc = cfs_kernel_thread(ptlrpc_main, &d, CLONE_VM | CLONE_FILES);
1678         if (rc < 0) {
1679                 CERROR("cannot start thread '%s': rc %d\n", name, rc);
1680
1681                 spin_lock(&svc->srv_lock);
1682                 list_del(&thread->t_link);
1683                 --svc->srv_threads_started;
1684                 spin_unlock(&svc->srv_lock);
1685
1686                 OBD_FREE(thread, sizeof(*thread));
1687                 RETURN(rc);
1688         }
1689         l_wait_event(thread->t_ctl_waitq,
1690                      thread->t_flags & (SVC_RUNNING | SVC_STOPPED), &lwi);
1691
1692         rc = (thread->t_flags & SVC_STOPPED) ? thread->t_id : 0;
1693         RETURN(rc);
1694 }
1695 #endif
1696
1697 int ptlrpc_unregister_service(struct ptlrpc_service *service)
1698 {
1699         int                   rc;
1700         struct l_wait_info    lwi;
1701         struct list_head     *tmp;
1702         struct ptlrpc_reply_state *rs, *t;
1703
1704         cfs_timer_disarm(&service->srv_at_timer);
1705
1706         ptlrpc_stop_all_threads(service);
1707         LASSERT(list_empty(&service->srv_threads));
1708
1709         spin_lock (&ptlrpc_all_services_lock);
1710         list_del_init (&service->srv_list);
1711         spin_unlock (&ptlrpc_all_services_lock);
1712
1713         ptlrpc_lprocfs_unregister_service(service);
1714
1715         /* All history will be culled when the next request buffer is
1716          * freed */
1717         service->srv_max_history_rqbds = 0;
1718
1719         CDEBUG(D_NET, "%s: tearing down\n", service->srv_name);
1720
1721         rc = LNetClearLazyPortal(service->srv_req_portal);
1722         LASSERT (rc == 0);
1723
1724         /* Unlink all the request buffers.  This forces a 'final' event with
1725          * its 'unlink' flag set for each posted rqbd */
1726         list_for_each(tmp, &service->srv_active_rqbds) {
1727                 struct ptlrpc_request_buffer_desc *rqbd =
1728                         list_entry(tmp, struct ptlrpc_request_buffer_desc,
1729                                    rqbd_list);
1730
1731                 rc = LNetMDUnlink(rqbd->rqbd_md_h);
1732                 LASSERT (rc == 0 || rc == -ENOENT);
1733         }
1734
1735         /* Wait for the network to release any buffers it's currently
1736          * filling */
1737         for (;;) {
1738                 spin_lock(&service->srv_lock);
1739                 rc = service->srv_nrqbd_receiving;
1740                 spin_unlock(&service->srv_lock);
1741
1742                 if (rc == 0)
1743                         break;
1744
1745                 /* Network access will complete in finite time but the HUGE
1746                  * timeout lets us CWARN for visibility of sluggish NALs */
1747                 lwi = LWI_TIMEOUT(cfs_time_seconds(LONG_UNLINK), NULL, NULL);
1748                 rc = l_wait_event(service->srv_waitq,
1749                                   service->srv_nrqbd_receiving == 0,
1750                                   &lwi);
1751                 if (rc == -ETIMEDOUT)
1752                         CWARN("Service %s waiting for request buffers\n",
1753                               service->srv_name);
1754         }
1755
1756         /* schedule all outstanding replies to terminate them */
1757         spin_lock(&service->srv_lock);
1758         while (!list_empty(&service->srv_active_replies)) {
1759                 struct ptlrpc_reply_state *rs =
1760                         list_entry(service->srv_active_replies.next,
1761                                    struct ptlrpc_reply_state, rs_list);
1762                 ptlrpc_schedule_difficult_reply(rs);
1763         }
1764         spin_unlock(&service->srv_lock);
1765
1766         /* purge the request queue.  NB No new replies (rqbds all unlinked)
1767          * and no service threads, so I'm the only thread noodling the
1768          * request queue now */
1769         while (!list_empty(&service->srv_req_in_queue)) {
1770                 struct ptlrpc_request *req =
1771                         list_entry(service->srv_req_in_queue.next,
1772                                    struct ptlrpc_request,
1773                                    rq_list);
1774
1775                 list_del(&req->rq_list);
1776                 service->srv_n_queued_reqs--;
1777                 service->srv_n_active_reqs++;
1778                 ptlrpc_server_free_request(req);
1779         }
1780         while (!list_empty(&service->srv_request_queue)) {
1781                 struct ptlrpc_request *req =
1782                         list_entry(service->srv_request_queue.next,
1783                                    struct ptlrpc_request,
1784                                    rq_list);
1785
1786                 list_del(&req->rq_list);
1787                 service->srv_n_queued_reqs--;
1788                 service->srv_n_active_reqs++;
1789
1790                 ptlrpc_server_free_request(req);
1791         }
1792         LASSERT(service->srv_n_queued_reqs == 0);
1793         LASSERT(service->srv_n_active_reqs == 0);
1794         LASSERT(service->srv_n_history_rqbds == 0);
1795         LASSERT(list_empty(&service->srv_active_rqbds));
1796
1797         /* Now free all the request buffers since nothing references them
1798          * any more... */
1799         while (!list_empty(&service->srv_idle_rqbds)) {
1800                 struct ptlrpc_request_buffer_desc *rqbd =
1801                         list_entry(service->srv_idle_rqbds.next,
1802                                    struct ptlrpc_request_buffer_desc,
1803                                    rqbd_list);
1804
1805                 ptlrpc_free_rqbd(rqbd);
1806         }
1807
1808         /* wait for all outstanding replies to complete (they were
1809          * scheduled having been flagged to abort above) */
1810         while (atomic_read(&service->srv_outstanding_replies) != 0) {
1811                 struct l_wait_info lwi = LWI_TIMEOUT(cfs_time_seconds(10), NULL, NULL);
1812
1813                 rc = l_wait_event(service->srv_waitq,
1814                                   !list_empty(&service->srv_reply_queue), &lwi);
1815                 LASSERT(rc == 0 || rc == -ETIMEDOUT);
1816
1817                 if (rc == 0) {
1818                         ptlrpc_server_handle_reply(service);
1819                         continue;
1820                 }
1821                 CWARN("Unexpectedly long timeout %p\n", service);
1822         }
1823
1824         list_for_each_entry_safe(rs, t, &service->srv_free_rs_list, rs_list) {
1825                 list_del(&rs->rs_list);
1826                 OBD_FREE(rs, service->srv_max_reply_size);
1827         }
1828
1829         /* In case somebody rearmed this in the meantime */
1830         cfs_timer_disarm(&service->srv_at_timer);
1831
1832         OBD_FREE_PTR(service);
1833         return 0;
1834 }
1835
1836 /* Returns 0 if the service is healthy.
1837  *
1838  * Right now, it just checks to make sure that requests aren't languishing
1839  * in the queue.  We'll use this health check to govern whether a node needs
1840  * to be shot, so it's intentionally non-aggressive. */
1841 int ptlrpc_service_health_check(struct ptlrpc_service *svc)
1842 {
1843         struct ptlrpc_request *request;
1844         struct timeval         right_now;
1845         long                   timediff;
1846
1847         if (svc == NULL)
1848                 return 0;
1849
1850         do_gettimeofday(&right_now);
1851
1852         spin_lock(&svc->srv_lock);
1853         if (list_empty(&svc->srv_request_queue)) {
1854                 spin_unlock(&svc->srv_lock);
1855                 return 0;
1856         }
1857
1858         /* How long has the next entry been waiting? */
1859         request = list_entry(svc->srv_request_queue.next,
1860                              struct ptlrpc_request, rq_list);
1861         timediff = cfs_timeval_sub(&right_now, &request->rq_arrival_time, NULL);
1862         spin_unlock(&svc->srv_lock);
1863
1864         if ((timediff / ONE_MILLION) > (AT_OFF ? obd_timeout * 3/2 :
1865                                         at_max)) {
1866                 CERROR("%s: unhealthy - request has been waiting %lds\n",
1867                        svc->srv_name, timediff / ONE_MILLION);
1868                 return (-1);
1869         }
1870
1871         return 0;
1872 }