lustre/osp/osp_sync.c

   1 /*
   2  * GPL HEADER START
   3  *
   4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 only,
   8  * as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * General Public License version 2 for more details (a copy is included
  14  * in the LICENSE file that accompanied this code).
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * version 2 along with this program; If not, see
  18  * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
  19  *
  20  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  21  * CA 95054 USA or visit www.sun.com if you need additional information or
  22  * have any questions.
  23  *
  24  * GPL HEADER END
  25  */
  26 /*
  27  * Copyright (c) 2007, 2010, Oracle and/or its affiliates. All rights reserved.
  28  * Use is subject to license terms.
  29  *
  30  * Copyright (c) 2012, 2013, Intel Corporation.
  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/osp/osp_sync.c
  37  *
  38  * Lustre OST Proxy Device
  39  *
  40  * Author: Alex Zhuravlev <alexey.zhuravlev@intel.com>
  41  * Author: Mikhail Pershin <mike.pershin@intel.com>
  42  */
  43
  44 #define DEBUG_SUBSYSTEM S_MDS
  45
  46 #include <lustre_log.h>
  47 #include "osp_internal.h"
  48
  49 static int osp_sync_id_traction_init(struct osp_device *d);
  50 static void osp_sync_id_traction_fini(struct osp_device *d);
  51 static __u32 osp_sync_id_get(struct osp_device *d, __u32 id);
  52 static void osp_sync_remove_from_tracker(struct osp_device *d);
  53
  54 /*
  55  * this is a components of OSP implementing synchronization between MDS and OST
  56  * it llogs all interesting changes (currently it's uig/gid change and object
  57  * destroy) atomically, then makes sure changes hit OST storage
  58  *
  59  * we have 4 queues of work:
  60  *
  61  * the first queue is llog itself, once read a change is stored in 2nd queue
  62  * in form of RPC (but RPC isn't fired yet).
  63  *
  64  * the second queue (opd_syn_waiting_for_commit) holds changes awaiting local
  65  * commit. once change is committed locally it migrates onto 3rd queue.
  66  *
  67  * the third queue (opd_syn_committed_here) holds changes committed locally,
  68  * but not sent to OST (as the pipe can be full). once pipe becomes non-full
  69  * we take a change from the queue and fire corresponded RPC.
  70  *
  71  * once RPC is reported committed by OST (using regular last_committed mech.)
  72  * the change jumps into 4th queue (opd_syn_committed_there), now we can
  73  * cancel corresponded llog record and release RPC
  74  *
  75  * opd_syn_changes is a number of unread llog records (to be processed).
  76  * notice this number doesn't include llog records from previous boots.
  77  * with OSP_SYN_THRESHOLD we try to batch processing a bit (TO BE IMPLEMENTED)
  78  *
  79  * opd_syn_rpc_in_progress is a number of requests in 2-4 queues.
  80  * we control this with OSP_MAX_IN_PROGRESS so that OSP don't consume
  81  * too much memory -- how to deal with 1000th OSTs ? batching could help?
  82  *
  83  * opd_syn_rpc_in_flight is a number of RPC in flight.
  84  * we control this with OSP_MAX_IN_FLIGHT
  85  */
  86
  87 /* XXX: do math to learn reasonable threshold
  88  * should it be ~ number of changes fitting bulk? */
  89
  90 #define OSP_SYN_THRESHOLD       10
  91 #define OSP_MAX_IN_FLIGHT       8
  92 #define OSP_MAX_IN_PROGRESS     4096
  93
  94 #define OSP_JOB_MAGIC           0x26112005
  95
  96 static inline int osp_sync_running(struct osp_device *d)
  97 {
  98         return !!(d->opd_syn_thread.t_flags & SVC_RUNNING);
  99 }
 100
 101 static inline int osp_sync_stopped(struct osp_device *d)
 102 {
 103         return !!(d->opd_syn_thread.t_flags & SVC_STOPPED);
 104 }
 105
 106 static inline int osp_sync_has_new_job(struct osp_device *d)
 107 {
 108         return ((d->opd_syn_last_processed_id < d->opd_syn_last_used_id) &&
 109                 (d->opd_syn_last_processed_id < d->opd_syn_last_committed_id))
 110                 || (d->opd_syn_prev_done == 0);
 111 }
 112
 113 static inline int osp_sync_low_in_progress(struct osp_device *d)
 114 {
 115         return d->opd_syn_rpc_in_progress < d->opd_syn_max_rpc_in_progress;
 116 }
 117
 118 static inline int osp_sync_low_in_flight(struct osp_device *d)
 119 {
 120         return d->opd_syn_rpc_in_flight < d->opd_syn_max_rpc_in_flight;
 121 }
 122
 123 static inline int osp_sync_has_work(struct osp_device *d)
 124 {
 125         /* has new/old changes and low in-progress? */
 126         if (osp_sync_has_new_job(d) && osp_sync_low_in_progress(d) &&
 127             osp_sync_low_in_flight(d) && d->opd_imp_connected)
 128                 return 1;
 129
 130         /* has remotely committed? */
 131         if (!cfs_list_empty(&d->opd_syn_committed_there))
 132                 return 1;
 133
 134         return 0;
 135 }
 136
 137 #define osp_sync_check_for_work(d)                      \
 138 {                                                       \
 139         if (osp_sync_has_work(d)) {                     \
 140                 wake_up(&d->opd_syn_waitq);    \
 141         }                                               \
 142 }
 143
 144 void __osp_sync_check_for_work(struct osp_device *d)
 145 {
 146         osp_sync_check_for_work(d);
 147 }
 148
 149 static inline int osp_sync_can_process_new(struct osp_device *d,
 150                                            struct llog_rec_hdr *rec)
 151 {
 152         LASSERT(d);
 153
 154         if (!osp_sync_low_in_progress(d))
 155                 return 0;
 156         if (!osp_sync_low_in_flight(d))
 157                 return 0;
 158         if (!d->opd_imp_connected)
 159                 return 0;
 160         if (d->opd_syn_prev_done == 0)
 161                 return 1;
 162         if (d->opd_syn_changes == 0)
 163                 return 0;
 164         if (rec == NULL || rec->lrh_id <= d->opd_syn_last_committed_id)
 165                 return 1;
 166         return 0;
 167 }
 168
 169 int osp_sync_declare_add(const struct lu_env *env, struct osp_object *o,
 170                          llog_op_type type, struct thandle *th)
 171 {
 172         struct osp_thread_info  *osi = osp_env_info(env);
 173         struct osp_device       *d = lu2osp_dev(o->opo_obj.do_lu.lo_dev);
 174         struct llog_ctxt        *ctxt;
 175         int                      rc;
 176
 177         ENTRY;
 178
 179         /* it's a layering violation, to access internals of th,
 180          * but we can do this as a sanity check, for a while */
 181         LASSERT(th->th_dev == d->opd_storage);
 182
 183         switch (type) {
 184         case MDS_UNLINK64_REC:
 185                 osi->osi_hdr.lrh_len = sizeof(struct llog_unlink64_rec);
 186                 break;
 187         case MDS_SETATTR64_REC:
 188                 osi->osi_hdr.lrh_len = sizeof(struct llog_setattr64_rec);
 189                 break;
 190         default:
 191                 LBUG();
 192         }
 193
 194         /* we want ->dt_trans_start() to allocate per-thandle structure */
 195         th->th_tags |= LCT_OSP_THREAD;
 196
 197         ctxt = llog_get_context(d->opd_obd, LLOG_MDS_OST_ORIG_CTXT);
 198         LASSERT(ctxt);
 199
 200         rc = llog_declare_add(env, ctxt->loc_handle, &osi->osi_hdr, th);
 201         llog_ctxt_put(ctxt);
 202
 203         RETURN(rc);
 204 }
 205
 206 static int osp_sync_add_rec(const struct lu_env *env, struct osp_device *d,
 207                             const struct lu_fid *fid, llog_op_type type,
 208                             int count, struct thandle *th,
 209                             const struct lu_attr *attr)
 210 {
 211         struct osp_thread_info  *osi = osp_env_info(env);
 212         struct llog_ctxt        *ctxt;
 213         struct osp_txn_info     *txn;
 214         int                      rc;
 215
 216         ENTRY;
 217
 218         /* it's a layering violation, to access internals of th,
 219          * but we can do this as a sanity check, for a while */
 220         LASSERT(th->th_dev == d->opd_storage);
 221
 222         switch (type) {
 223         case MDS_UNLINK64_REC:
 224                 osi->osi_hdr.lrh_len = sizeof(osi->osi_unlink);
 225                 osi->osi_hdr.lrh_type = MDS_UNLINK64_REC;
 226                 osi->osi_unlink.lur_fid  = *fid;
 227                 osi->osi_unlink.lur_count = count;
 228                 break;
 229         case MDS_SETATTR64_REC:
 230                 rc = fid_to_ostid(fid, &osi->osi_oi);
 231                 LASSERT(rc == 0);
 232                 osi->osi_hdr.lrh_len = sizeof(osi->osi_setattr);
 233                 osi->osi_hdr.lrh_type = MDS_SETATTR64_REC;
 234                 osi->osi_setattr.lsr_oi  = osi->osi_oi;
 235                 LASSERT(attr);
 236                 osi->osi_setattr.lsr_uid = attr->la_uid;
 237                 osi->osi_setattr.lsr_gid = attr->la_gid;
 238                 break;
 239         default:
 240                 LBUG();
 241         }
 242
 243         txn = osp_txn_info(&th->th_ctx);
 244         LASSERT(txn);
 245
 246         txn->oti_current_id = osp_sync_id_get(d, txn->oti_current_id);
 247         osi->osi_hdr.lrh_id = txn->oti_current_id;
 248
 249         ctxt = llog_get_context(d->opd_obd, LLOG_MDS_OST_ORIG_CTXT);
 250         if (ctxt == NULL)
 251                 RETURN(-ENOMEM);
 252         rc = llog_add(env, ctxt->loc_handle, &osi->osi_hdr, &osi->osi_cookie,
 253                       NULL, th);
 254         llog_ctxt_put(ctxt);
 255
 256         CDEBUG(D_OTHER, "%s: new record "DOSTID":%lu/%lu: %d\n",
 257                d->opd_obd->obd_name, POSTID(&osi->osi_cookie.lgc_lgl.lgl_oi),
 258                (unsigned long) osi->osi_cookie.lgc_lgl.lgl_ogen,
 259                (unsigned long) osi->osi_cookie.lgc_index, rc);
 260
 261         if (rc > 0)
 262                 rc = 0;
 263
 264         if (likely(rc == 0)) {
 265                 spin_lock(&d->opd_syn_lock);
 266                 d->opd_syn_changes++;
 267                 spin_unlock(&d->opd_syn_lock);
 268         }
 269
 270         RETURN(rc);
 271 }
 272
 273 int osp_sync_add(const struct lu_env *env, struct osp_object *o,
 274                  llog_op_type type, struct thandle *th,
 275                  const struct lu_attr *attr)
 276 {
 277         return osp_sync_add_rec(env, lu2osp_dev(o->opo_obj.do_lu.lo_dev),
 278                                 lu_object_fid(&o->opo_obj.do_lu), type, 1,
 279                                 th, attr);
 280 }
 281
 282 int osp_sync_gap(const struct lu_env *env, struct osp_device *d,
 283                  struct lu_fid *fid, int lost, struct thandle *th)
 284 {
 285         return osp_sync_add_rec(env, d, fid, MDS_UNLINK64_REC, lost, th, NULL);
 286 }
 287
 288 /*
 289  * it's quite obvious we can't maintain all the structures in the memory:
 290  * while OST is down, MDS can be processing thousands and thousands of unlinks
 291  * filling persistent llogs and in-core respresentation
 292  *
 293  * this doesn't scale at all. so we need basically the following:
 294  * a) destroy/setattr append llog records
 295  * b) once llog has grown to X records, we process first Y committed records
 296  *
 297  *  once record R is found via llog_process(), it becomes committed after any
 298  *  subsequent commit callback (at the most)
 299  */
 300
 301 /*
 302  * called for each atomic on-disk change (not once per transaction batch)
 303  * and goes over the list
 304  * XXX: should be optimized?
 305  */
 306
 307 /**
 308  * called for each RPC reported committed
 309  */
 310 static void osp_sync_request_commit_cb(struct ptlrpc_request *req)
 311 {
 312         struct osp_device *d = req->rq_cb_data;
 313
 314         CDEBUG(D_HA, "commit req %p, transno "LPU64"\n", req, req->rq_transno);
 315
 316         if (unlikely(req->rq_transno == 0))
 317                 return;
 318
 319         /* do not do any opd_dyn_rpc_* accounting here
 320          * it's done in osp_sync_interpret sooner or later */
 321
 322         LASSERT(d);
 323         LASSERT(req->rq_svc_thread == (void *) OSP_JOB_MAGIC);
 324         LASSERT(cfs_list_empty(&req->rq_exp_list));
 325
 326         ptlrpc_request_addref(req);
 327
 328         spin_lock(&d->opd_syn_lock);
 329         cfs_list_add(&req->rq_exp_list, &d->opd_syn_committed_there);
 330         spin_unlock(&d->opd_syn_lock);
 331
 332         /* XXX: some batching wouldn't hurt */
 333         wake_up(&d->opd_syn_waitq);
 334 }
 335
 336 static int osp_sync_interpret(const struct lu_env *env,
 337                               struct ptlrpc_request *req, void *aa, int rc)
 338 {
 339         struct osp_device *d = req->rq_cb_data;
 340
 341         if (req->rq_svc_thread != (void *) OSP_JOB_MAGIC)
 342                 DEBUG_REQ(D_ERROR, req, "bad magic %p\n", req->rq_svc_thread);
 343         LASSERT(req->rq_svc_thread == (void *) OSP_JOB_MAGIC);
 344         LASSERT(d);
 345
 346         CDEBUG(D_HA, "reply req %p/%d, rc %d, transno %u\n", req,
 347                cfs_atomic_read(&req->rq_refcount),
 348                rc, (unsigned) req->rq_transno);
 349         LASSERT(rc || req->rq_transno);
 350
 351         if (rc == -ENOENT) {
 352                 /*
 353                  * we tried to destroy object or update attributes,
 354                  * but object doesn't exist anymore - cancell llog record
 355                  */
 356                 LASSERT(req->rq_transno == 0);
 357                 LASSERT(cfs_list_empty(&req->rq_exp_list));
 358
 359                 ptlrpc_request_addref(req);
 360
 361                 spin_lock(&d->opd_syn_lock);
 362                 cfs_list_add(&req->rq_exp_list, &d->opd_syn_committed_there);
 363                 spin_unlock(&d->opd_syn_lock);
 364
 365                 wake_up(&d->opd_syn_waitq);
 366         } else if (rc) {
 367                 struct obd_import *imp = req->rq_import;
 368                 /*
 369                  * error happened, we'll try to repeat on next boot ?
 370                  */
 371                 LASSERTF(req->rq_transno == 0 ||
 372                          req->rq_import_generation < imp->imp_generation,
 373                          "transno "LPU64", rc %d, gen: req %d, imp %d\n",
 374                          req->rq_transno, rc, req->rq_import_generation,
 375                          imp->imp_generation);
 376                 if (req->rq_transno == 0) {
 377                         /* this is the last time we see the request
 378                          * if transno is not zero, then commit cb
 379                          * will be called at some point */
 380                         LASSERT(d->opd_syn_rpc_in_progress > 0);
 381                         spin_lock(&d->opd_syn_lock);
 382                         d->opd_syn_rpc_in_progress--;
 383                         spin_unlock(&d->opd_syn_lock);
 384                 }
 385
 386                 wake_up(&d->opd_syn_waitq);
 387         } else if (unlikely(d->opd_pre_status == -ENOSPC)) {
 388                 /*
 389                  * if current status is -ENOSPC (lack of free space on OST)
 390                  * then we should poll OST immediately once object destroy
 391                  * is replied
 392                  */
 393                 osp_statfs_need_now(d);
 394         }
 395
 396         LASSERT(d->opd_syn_rpc_in_flight > 0);
 397         spin_lock(&d->opd_syn_lock);
 398         d->opd_syn_rpc_in_flight--;
 399         spin_unlock(&d->opd_syn_lock);
 400         CDEBUG(D_OTHER, "%s: %d in flight, %d in progress\n",
 401                d->opd_obd->obd_name, d->opd_syn_rpc_in_flight,
 402                d->opd_syn_rpc_in_progress);
 403
 404         osp_sync_check_for_work(d);
 405
 406         return 0;
 407 }
 408
 409 /*
 410  * the function walks through list of committed locally changes
 411  * and send them to RPC until the pipe is full
 412  */
 413 static void osp_sync_send_new_rpc(struct osp_device *d,
 414                                   struct ptlrpc_request *req)
 415 {
 416         LASSERT(d->opd_syn_rpc_in_flight <= d->opd_syn_max_rpc_in_flight);
 417         LASSERT(req->rq_svc_thread == (void *) OSP_JOB_MAGIC);
 418
 419         ptlrpcd_add_req(req, PDL_POLICY_ROUND, -1);
 420 }
 421
 422 static struct ptlrpc_request *osp_sync_new_job(struct osp_device *d,
 423                                                struct llog_handle *llh,
 424                                                struct llog_rec_hdr *h,
 425                                                ost_cmd_t op,
 426                                                const struct req_format *format)
 427 {
 428         struct ptlrpc_request   *req;
 429         struct ost_body         *body;
 430         struct obd_import       *imp;
 431         int                      rc;
 432
 433         /* Prepare the request */
 434         imp = d->opd_obd->u.cli.cl_import;
 435         LASSERT(imp);
 436         req = ptlrpc_request_alloc(imp, format);
 437         if (req == NULL)
 438                 RETURN(ERR_PTR(-ENOMEM));
 439
 440         rc = ptlrpc_request_pack(req, LUSTRE_OST_VERSION, op);
 441         if (rc) {
 442                 ptlrpc_req_finished(req);
 443                 return ERR_PTR(rc);
 444         }
 445
 446         /*
 447          * this is a trick: to save on memory allocations we put cookie
 448          * into the request, but don't set corresponded flag in o_valid
 449          * so that OST doesn't interpret this cookie. once the request
 450          * is committed on OST we take cookie from the request and cancel
 451          */
 452         body = req_capsule_client_get(&req->rq_pill, &RMF_OST_BODY);
 453         LASSERT(body);
 454         body->oa.o_lcookie.lgc_lgl = llh->lgh_id;
 455         body->oa.o_lcookie.lgc_subsys = LLOG_MDS_OST_ORIG_CTXT;
 456         body->oa.o_lcookie.lgc_index = h->lrh_index;
 457         CFS_INIT_LIST_HEAD(&req->rq_exp_list);
 458         req->rq_svc_thread = (void *) OSP_JOB_MAGIC;
 459
 460         req->rq_interpret_reply = osp_sync_interpret;
 461         req->rq_commit_cb = osp_sync_request_commit_cb;
 462         req->rq_cb_data = d;
 463
 464         ptlrpc_request_set_replen(req);
 465
 466         return req;
 467 }
 468
 469 static int osp_sync_new_setattr_job(struct osp_device *d,
 470                                     struct llog_handle *llh,
 471                                     struct llog_rec_hdr *h)
 472 {
 473         struct llog_setattr64_rec       *rec = (struct llog_setattr64_rec *)h;
 474         struct ptlrpc_request           *req;
 475         struct ost_body                 *body;
 476
 477         ENTRY;
 478         LASSERT(h->lrh_type == MDS_SETATTR64_REC);
 479
 480         req = osp_sync_new_job(d, llh, h, OST_SETATTR, &RQF_OST_SETATTR);
 481         if (IS_ERR(req))
 482                 RETURN(PTR_ERR(req));
 483
 484         body = req_capsule_client_get(&req->rq_pill, &RMF_OST_BODY);
 485         LASSERT(body);
 486         body->oa.o_oi = rec->lsr_oi;
 487         body->oa.o_uid = rec->lsr_uid;
 488         body->oa.o_gid = rec->lsr_gid;
 489         body->oa.o_valid = OBD_MD_FLGROUP | OBD_MD_FLID |
 490                            OBD_MD_FLUID | OBD_MD_FLGID;
 491
 492         osp_sync_send_new_rpc(d, req);
 493         RETURN(0);
 494 }
 495
 496 /* Old records may be in old format, so we handle that too */
 497 static int osp_sync_new_unlink_job(struct osp_device *d,
 498                                    struct llog_handle *llh,
 499                                    struct llog_rec_hdr *h)
 500 {
 501         struct llog_unlink_rec  *rec = (struct llog_unlink_rec *)h;
 502         struct ptlrpc_request   *req;
 503         struct ost_body         *body;
 504
 505         ENTRY;
 506         LASSERT(h->lrh_type == MDS_UNLINK_REC);
 507
 508         req = osp_sync_new_job(d, llh, h, OST_DESTROY, &RQF_OST_DESTROY);
 509         if (IS_ERR(req))
 510                 RETURN(PTR_ERR(req));
 511
 512         body = req_capsule_client_get(&req->rq_pill, &RMF_OST_BODY);
 513         LASSERT(body);
 514         ostid_set_seq(&body->oa.o_oi, rec->lur_oseq);
 515         ostid_set_id(&body->oa.o_oi, rec->lur_oid);
 516         body->oa.o_misc = rec->lur_count;
 517         body->oa.o_valid = OBD_MD_FLGROUP | OBD_MD_FLID;
 518         if (rec->lur_count)
 519                 body->oa.o_valid |= OBD_MD_FLOBJCOUNT;
 520
 521         osp_sync_send_new_rpc(d, req);
 522         RETURN(0);
 523 }
 524
 525 static int osp_sync_new_unlink64_job(struct osp_device *d,
 526                                      struct llog_handle *llh,
 527                                      struct llog_rec_hdr *h)
 528 {
 529         struct llog_unlink64_rec        *rec = (struct llog_unlink64_rec *)h;
 530         struct ptlrpc_request           *req;
 531         struct ost_body                 *body;
 532         int                              rc;
 533
 534         ENTRY;
 535         LASSERT(h->lrh_type == MDS_UNLINK64_REC);
 536
 537         req = osp_sync_new_job(d, llh, h, OST_DESTROY, &RQF_OST_DESTROY);
 538         if (IS_ERR(req))
 539                 RETURN(PTR_ERR(req));
 540
 541         body = req_capsule_client_get(&req->rq_pill, &RMF_OST_BODY);
 542         if (body == NULL)
 543                 RETURN(-EFAULT);
 544         rc = fid_to_ostid(&rec->lur_fid, &body->oa.o_oi);
 545         if (rc < 0)
 546                 RETURN(rc);
 547         body->oa.o_misc = rec->lur_count;
 548         body->oa.o_valid = OBD_MD_FLGROUP | OBD_MD_FLID | OBD_MD_FLOBJCOUNT;
 549
 550         osp_sync_send_new_rpc(d, req);
 551         RETURN(0);
 552 }
 553
 554 static int osp_sync_process_record(const struct lu_env *env,
 555                                    struct osp_device *d,
 556                                    struct llog_handle *llh,
 557                                    struct llog_rec_hdr *rec)
 558 {
 559         struct llog_cookie       cookie;
 560         int                      rc = 0;
 561
 562         cookie.lgc_lgl = llh->lgh_id;
 563         cookie.lgc_subsys = LLOG_MDS_OST_ORIG_CTXT;
 564         cookie.lgc_index = rec->lrh_index;
 565
 566         if (unlikely(rec->lrh_type == LLOG_GEN_REC)) {
 567                 struct llog_gen_rec *gen = (struct llog_gen_rec *)rec;
 568
 569                 /* we're waiting for the record generated by this instance */
 570                 LASSERT(d->opd_syn_prev_done == 0);
 571                 if (!memcmp(&d->opd_syn_generation, &gen->lgr_gen,
 572                             sizeof(gen->lgr_gen))) {
 573                         CDEBUG(D_HA, "processed all old entries\n");
 574                         d->opd_syn_prev_done = 1;
 575                 }
 576
 577                 /* cancel any generation record */
 578                 rc = llog_cat_cancel_records(env, llh->u.phd.phd_cat_handle,
 579                                              1, &cookie);
 580
 581                 return rc;
 582         }
 583
 584         /*
 585          * now we prepare and fill requests to OST, put them on the queue
 586          * and fire after next commit callback
 587          */
 588
 589         /* notice we increment counters before sending RPC, to be consistent
 590          * in RPC interpret callback which may happen very quickly */
 591         spin_lock(&d->opd_syn_lock);
 592         d->opd_syn_rpc_in_flight++;
 593         d->opd_syn_rpc_in_progress++;
 594         spin_unlock(&d->opd_syn_lock);
 595
 596         switch (rec->lrh_type) {
 597         /* case MDS_UNLINK_REC is kept for compatibility */
 598         case MDS_UNLINK_REC:
 599                 rc = osp_sync_new_unlink_job(d, llh, rec);
 600                 break;
 601         case MDS_UNLINK64_REC:
 602                 rc = osp_sync_new_unlink64_job(d, llh, rec);
 603                 break;
 604         case MDS_SETATTR64_REC:
 605                 rc = osp_sync_new_setattr_job(d, llh, rec);
 606                 break;
 607         default:
 608                 CERROR("unknown record type: %x\n", rec->lrh_type);
 609                        rc = -EINVAL;
 610                        break;
 611         }
 612
 613         if (likely(rc == 0)) {
 614                 spin_lock(&d->opd_syn_lock);
 615                 if (d->opd_syn_prev_done) {
 616                         LASSERT(d->opd_syn_changes > 0);
 617                         LASSERT(rec->lrh_id <= d->opd_syn_last_committed_id);
 618                         /*
 619                          * NOTE: it's possible to meet same id if
 620                          * OST stores few stripes of same file
 621                          */
 622                         if (rec->lrh_id > d->opd_syn_last_processed_id)
 623                                 d->opd_syn_last_processed_id = rec->lrh_id;
 624
 625                         d->opd_syn_changes--;
 626                 }
 627                 CDEBUG(D_OTHER, "%s: %d in flight, %d in progress\n",
 628                        d->opd_obd->obd_name, d->opd_syn_rpc_in_flight,
 629                        d->opd_syn_rpc_in_progress);
 630                 spin_unlock(&d->opd_syn_lock);
 631         } else {
 632                 spin_lock(&d->opd_syn_lock);
 633                 d->opd_syn_rpc_in_flight--;
 634                 d->opd_syn_rpc_in_progress--;
 635                 spin_unlock(&d->opd_syn_lock);
 636         }
 637
 638         CDEBUG(D_HA, "found record %x, %d, idx %u, id %u: %d\n",
 639                rec->lrh_type, rec->lrh_len, rec->lrh_index, rec->lrh_id, rc);
 640         return rc;
 641 }
 642
 643 static void osp_sync_process_committed(const struct lu_env *env,
 644                                        struct osp_device *d)
 645 {
 646         struct obd_device       *obd = d->opd_obd;
 647         struct obd_import       *imp = obd->u.cli.cl_import;
 648         struct ost_body         *body;
 649         struct ptlrpc_request   *req, *tmp;
 650         struct llog_ctxt        *ctxt;
 651         struct llog_handle      *llh;
 652         cfs_list_t               list;
 653         int                      rc, done = 0;
 654
 655         ENTRY;
 656
 657         if (cfs_list_empty(&d->opd_syn_committed_there))
 658                 return;
 659
 660         /*
 661          * if current status is -ENOSPC (lack of free space on OST)
 662          * then we should poll OST immediately once object destroy
 663          * is committed.
 664          * notice: we do this upon commit as well because some backends
 665          * (like DMU) do not release space right away.
 666          */
 667         if (unlikely(d->opd_pre_status == -ENOSPC))
 668                 osp_statfs_need_now(d);
 669
 670         /*
 671          * now cancel them all
 672          * XXX: can we improve this using some batching?
 673          *      with batch RPC that'll happen automatically?
 674          * XXX: can we store ctxt in lod_device and save few cycles ?
 675          */
 676         ctxt = llog_get_context(obd, LLOG_MDS_OST_ORIG_CTXT);
 677         LASSERT(ctxt);
 678
 679         llh = ctxt->loc_handle;
 680         LASSERT(llh);
 681
 682         CFS_INIT_LIST_HEAD(&list);
 683         spin_lock(&d->opd_syn_lock);
 684         cfs_list_splice(&d->opd_syn_committed_there, &list);
 685         CFS_INIT_LIST_HEAD(&d->opd_syn_committed_there);
 686         spin_unlock(&d->opd_syn_lock);
 687
 688         cfs_list_for_each_entry_safe(req, tmp, &list, rq_exp_list) {
 689                 LASSERT(req->rq_svc_thread == (void *) OSP_JOB_MAGIC);
 690                 cfs_list_del_init(&req->rq_exp_list);
 691
 692                 body = req_capsule_client_get(&req->rq_pill, &RMF_OST_BODY);
 693                 LASSERT(body);
 694
 695                 /* import can be closing, thus all commit cb's are
 696                  * called we can check committness directly */
 697                 if (req->rq_transno <= imp->imp_peer_committed_transno) {
 698                         rc = llog_cat_cancel_records(env, llh, 1,
 699                                                      &body->oa.o_lcookie);
 700                         if (rc)
 701                                 CERROR("%s: can't cancel record: %d\n",
 702                                        obd->obd_name, rc);
 703                 } else {
 704                         DEBUG_REQ(D_HA, req, "not committed");
 705                 }
 706
 707                 ptlrpc_req_finished(req);
 708                 done++;
 709         }
 710
 711         llog_ctxt_put(ctxt);
 712
 713         LASSERT(d->opd_syn_rpc_in_progress >= done);
 714         spin_lock(&d->opd_syn_lock);
 715         d->opd_syn_rpc_in_progress -= done;
 716         spin_unlock(&d->opd_syn_lock);
 717         CDEBUG(D_OTHER, "%s: %d in flight, %d in progress\n",
 718                d->opd_obd->obd_name, d->opd_syn_rpc_in_flight,
 719                d->opd_syn_rpc_in_progress);
 720
 721         osp_sync_check_for_work(d);
 722
 723         /* wake up the thread if requested to stop:
 724          * it might be waiting for in-progress to complete */
 725         if (unlikely(osp_sync_running(d) == 0))
 726                 wake_up(&d->opd_syn_waitq);
 727
 728         EXIT;
 729 }
 730
 731 /*
 732  * this is where most of queues processing happens
 733  */
 734 static int osp_sync_process_queues(const struct lu_env *env,
 735                                    struct llog_handle *llh,
 736                                    struct llog_rec_hdr *rec,
 737                                    void *data)
 738 {
 739         struct osp_device       *d = data;
 740         int                      rc;
 741
 742         do {
 743                 struct l_wait_info lwi = { 0 };
 744
 745                 if (!osp_sync_running(d)) {
 746                         CDEBUG(D_HA, "stop llog processing\n");
 747                         return LLOG_PROC_BREAK;
 748                 }
 749
 750                 /* process requests committed by OST */
 751                 osp_sync_process_committed(env, d);
 752
 753                 /* if we there are changes to be processed and we have
 754                  * resources for this ... do now */
 755                 if (osp_sync_can_process_new(d, rec)) {
 756                         if (llh == NULL) {
 757                                 /* ask llog for another record */
 758                                 CDEBUG(D_HA, "%lu changes, %u in progress, %u in flight\n",
 759                                        d->opd_syn_changes,
 760                                        d->opd_syn_rpc_in_progress,
 761                                        d->opd_syn_rpc_in_flight);
 762                                 return 0;
 763                         }
 764
 765                         /*
 766                          * try to send, in case of disconnection, suspend
 767                          * processing till we can send this request
 768                          */
 769                         do {
 770                                 rc = osp_sync_process_record(env, d, llh, rec);
 771                                 /*
 772                                  * XXX: probably different handling is needed
 773                                  * for some bugs, like immediate exit or if
 774                                  * OSP gets inactive
 775                                  */
 776                                 if (rc) {
 777                                         CERROR("can't send: %d\n", rc);
 778                                         l_wait_event(d->opd_syn_waitq,
 779                                                      !osp_sync_running(d) ||
 780                                                      osp_sync_has_work(d),
 781                                                      &lwi);
 782                                 }
 783                         } while (rc != 0 && osp_sync_running(d));
 784
 785                         llh = NULL;
 786                         rec = NULL;
 787                 }
 788
 789                 if (d->opd_syn_last_processed_id == d->opd_syn_last_used_id)
 790                         osp_sync_remove_from_tracker(d);
 791
 792                 l_wait_event(d->opd_syn_waitq,
 793                              !osp_sync_running(d) ||
 794                              osp_sync_can_process_new(d, rec) ||
 795                              !cfs_list_empty(&d->opd_syn_committed_there),
 796                              &lwi);
 797         } while (1);
 798 }
 799
 800 /*
 801  * this thread runs llog_cat_process() scanner calling our callback
 802  * to process llog records. in the callback we implement tricky
 803  * state machine as we don't want to start scanning of the llog again
 804  * and again, also we don't want to process too many records and send
 805  * too many RPCs a time. so, depending on current load (num of changes
 806  * being synced to OST) the callback can suspend awaiting for some
 807  * new conditions, like syncs completed.
 808  *
 809  * in order to process llog records left by previous boots and to allow
 810  * llog_process_thread() to find something (otherwise it'd just exit
 811  * immediately) we add a special GENERATATION record on each boot.
 812  */
 813 static int osp_sync_thread(void *_arg)
 814 {
 815         struct osp_device       *d = _arg;
 816         struct ptlrpc_thread    *thread = &d->opd_syn_thread;
 817         struct l_wait_info       lwi = { 0 };
 818         struct llog_ctxt        *ctxt;
 819         struct obd_device       *obd = d->opd_obd;
 820         struct llog_handle      *llh;
 821         struct lu_env            env;
 822         int                      rc, count;
 823
 824         ENTRY;
 825
 826         rc = lu_env_init(&env, LCT_LOCAL);
 827         if (rc) {
 828                 CERROR("%s: can't initialize env: rc = %d\n",
 829                        obd->obd_name, rc);
 830                 RETURN(rc);
 831         }
 832
 833         spin_lock(&d->opd_syn_lock);
 834         thread->t_flags = SVC_RUNNING;
 835         spin_unlock(&d->opd_syn_lock);
 836         wake_up(&thread->t_ctl_waitq);
 837
 838         ctxt = llog_get_context(obd, LLOG_MDS_OST_ORIG_CTXT);
 839         if (ctxt == NULL) {
 840                 CERROR("can't get appropriate context\n");
 841                 GOTO(out, rc = -EINVAL);
 842         }
 843
 844         llh = ctxt->loc_handle;
 845         if (llh == NULL) {
 846                 CERROR("can't get llh\n");
 847                 llog_ctxt_put(ctxt);
 848                 GOTO(out, rc = -EINVAL);
 849         }
 850
 851         rc = llog_cat_process(&env, llh, osp_sync_process_queues, d, 0, 0);
 852         LASSERTF(rc == 0 || rc == LLOG_PROC_BREAK,
 853                  "%lu changes, %u in progress, %u in flight: %d\n",
 854                  d->opd_syn_changes, d->opd_syn_rpc_in_progress,
 855                  d->opd_syn_rpc_in_flight, rc);
 856
 857         /* we don't expect llog_process_thread() to exit till umount */
 858         LASSERTF(thread->t_flags != SVC_RUNNING,
 859                  "%lu changes, %u in progress, %u in flight\n",
 860                  d->opd_syn_changes, d->opd_syn_rpc_in_progress,
 861                  d->opd_syn_rpc_in_flight);
 862
 863         /* wait till all the requests are completed */
 864         count = 0;
 865         while (d->opd_syn_rpc_in_progress > 0) {
 866                 osp_sync_process_committed(&env, d);
 867
 868                 lwi = LWI_TIMEOUT(cfs_time_seconds(5), NULL, NULL);
 869                 rc = l_wait_event(d->opd_syn_waitq,
 870                                   d->opd_syn_rpc_in_progress == 0,
 871                                   &lwi);
 872                 if (rc == -ETIMEDOUT)
 873                         count++;
 874                 LASSERTF(count < 10, "%s: %d %d %sempty\n",
 875                          d->opd_obd->obd_name, d->opd_syn_rpc_in_progress,
 876                          d->opd_syn_rpc_in_flight,
 877                          cfs_list_empty(&d->opd_syn_committed_there) ? "" :"!");
 878
 879         }
 880
 881         llog_cat_close(&env, llh);
 882         rc = llog_cleanup(&env, ctxt);
 883         if (rc)
 884                 CERROR("can't cleanup llog: %d\n", rc);
 885 out:
 886         LASSERTF(d->opd_syn_rpc_in_progress == 0,
 887                  "%s: %d %d %sempty\n",
 888                  d->opd_obd->obd_name, d->opd_syn_rpc_in_progress,
 889                  d->opd_syn_rpc_in_flight,
 890                  cfs_list_empty(&d->opd_syn_committed_there) ? "" : "!");
 891
 892         thread->t_flags = SVC_STOPPED;
 893
 894         wake_up(&thread->t_ctl_waitq);
 895
 896         lu_env_fini(&env);
 897
 898         RETURN(0);
 899 }
 900
 901 static int osp_sync_llog_init(const struct lu_env *env, struct osp_device *d)
 902 {
 903         struct osp_thread_info *osi = osp_env_info(env);
 904         struct llog_handle     *lgh = NULL;
 905         struct obd_device      *obd = d->opd_obd;
 906         struct llog_ctxt       *ctxt;
 907         int                     rc;
 908
 909         ENTRY;
 910
 911         LASSERT(obd);
 912
 913         /*
 914          * open llog corresponding to our OST
 915          */
 916         OBD_SET_CTXT_MAGIC(&obd->obd_lvfs_ctxt);
 917         obd->obd_lvfs_ctxt.dt = d->opd_storage;
 918
 919         rc = llog_osd_get_cat_list(env, d->opd_storage, d->opd_index, 1,
 920                                    &osi->osi_cid);
 921         if (rc) {
 922                 CERROR("%s: can't get id from catalogs: rc = %d\n",
 923                        obd->obd_name, rc);
 924                 RETURN(rc);
 925         }
 926
 927         CDEBUG(D_INFO, "%s: Init llog for %d - catid "DOSTID":%x\n",
 928                obd->obd_name, d->opd_index,
 929                POSTID(&osi->osi_cid.lci_logid.lgl_oi),
 930                osi->osi_cid.lci_logid.lgl_ogen);
 931
 932         rc = llog_setup(env, obd, &obd->obd_olg, LLOG_MDS_OST_ORIG_CTXT, obd,
 933                         &osp_mds_ost_orig_logops);
 934         if (rc)
 935                 RETURN(rc);
 936
 937         ctxt = llog_get_context(obd, LLOG_MDS_OST_ORIG_CTXT);
 938         LASSERT(ctxt);
 939
 940         if (likely(logid_id(&osi->osi_cid.lci_logid) != 0)) {
 941                 rc = llog_open(env, ctxt, &lgh, &osi->osi_cid.lci_logid, NULL,
 942                                LLOG_OPEN_EXISTS);
 943                 /* re-create llog if it is missing */
 944                 if (rc == -ENOENT)
 945                         logid_set_id(&osi->osi_cid.lci_logid, 0);
 946                 else if (rc < 0)
 947                         GOTO(out_cleanup, rc);
 948         }
 949
 950         if (unlikely(logid_id(&osi->osi_cid.lci_logid) == 0)) {
 951                 rc = llog_open_create(env, ctxt, &lgh, NULL, NULL);
 952                 if (rc < 0)
 953                         GOTO(out_cleanup, rc);
 954                 osi->osi_cid.lci_logid = lgh->lgh_id;
 955         }
 956
 957         LASSERT(lgh != NULL);
 958         ctxt->loc_handle = lgh;
 959
 960         rc = llog_cat_init_and_process(env, lgh);
 961         if (rc)
 962                 GOTO(out_close, rc);
 963
 964         rc = llog_osd_put_cat_list(env, d->opd_storage, d->opd_index, 1,
 965                                    &osi->osi_cid);
 966         if (rc)
 967                 GOTO(out_close, rc);
 968
 969         /*
 970          * put a mark in the llog till which we'll be processing
 971          * old records restless
 972          */
 973         d->opd_syn_generation.mnt_cnt = cfs_time_current();
 974         d->opd_syn_generation.conn_cnt = cfs_time_current();
 975
 976         osi->osi_hdr.lrh_type = LLOG_GEN_REC;
 977         osi->osi_hdr.lrh_len = sizeof(osi->osi_gen);
 978
 979         memcpy(&osi->osi_gen.lgr_gen, &d->opd_syn_generation,
 980                sizeof(osi->osi_gen.lgr_gen));
 981
 982         rc = llog_cat_add(env, lgh, &osi->osi_gen.lgr_hdr, &osi->osi_cookie,
 983                           NULL);
 984         if (rc < 0)
 985                 GOTO(out_close, rc);
 986         llog_ctxt_put(ctxt);
 987         RETURN(0);
 988 out_close:
 989         llog_cat_close(env, lgh);
 990 out_cleanup:
 991         llog_cleanup(env, ctxt);
 992         RETURN(rc);
 993 }
 994
 995 static void osp_sync_llog_fini(const struct lu_env *env, struct osp_device *d)
 996 {
 997         struct llog_ctxt *ctxt;
 998
 999         ctxt = llog_get_context(d->opd_obd, LLOG_MDS_OST_ORIG_CTXT);
1000         if (ctxt != NULL)
1001                 llog_cat_close(env, ctxt->loc_handle);
1002         llog_cleanup(env, ctxt);
1003 }
1004
1005 /*
1006  * initializes sync component of OSP
1007  */
1008 int osp_sync_init(const struct lu_env *env, struct osp_device *d)
1009 {
1010         struct l_wait_info       lwi = { 0 };
1011         int                      rc;
1012
1013         ENTRY;
1014
1015         rc = osp_sync_id_traction_init(d);
1016         if (rc)
1017                 RETURN(rc);
1018
1019         /*
1020          * initialize llog storing changes
1021          */
1022         rc = osp_sync_llog_init(env, d);
1023         if (rc) {
1024                 CERROR("%s: can't initialize llog: rc = %d\n",
1025                        d->opd_obd->obd_name, rc);
1026                 GOTO(err_id, rc);
1027         }
1028
1029         /*
1030          * Start synchronization thread
1031          */
1032         d->opd_syn_max_rpc_in_flight = OSP_MAX_IN_FLIGHT;
1033         d->opd_syn_max_rpc_in_progress = OSP_MAX_IN_PROGRESS;
1034         spin_lock_init(&d->opd_syn_lock);
1035         init_waitqueue_head(&d->opd_syn_waitq);
1036         init_waitqueue_head(&d->opd_syn_thread.t_ctl_waitq);
1037         CFS_INIT_LIST_HEAD(&d->opd_syn_committed_there);
1038
1039         rc = PTR_ERR(kthread_run(osp_sync_thread, d,
1040                                  "osp-syn-%u", d->opd_index));
1041         if (IS_ERR_VALUE(rc)) {
1042                 CERROR("%s: can't start sync thread: rc = %d\n",
1043                        d->opd_obd->obd_name, rc);
1044                 GOTO(err_llog, rc);
1045         }
1046
1047         l_wait_event(d->opd_syn_thread.t_ctl_waitq,
1048                      osp_sync_running(d) || osp_sync_stopped(d), &lwi);
1049
1050         RETURN(0);
1051 err_llog:
1052         osp_sync_llog_fini(env, d);
1053 err_id:
1054         osp_sync_id_traction_fini(d);
1055         return rc;
1056 }
1057
1058 int osp_sync_fini(struct osp_device *d)
1059 {
1060         struct ptlrpc_thread *thread = &d->opd_syn_thread;
1061
1062         ENTRY;
1063
1064         thread->t_flags = SVC_STOPPING;
1065         wake_up(&d->opd_syn_waitq);
1066         wait_event(thread->t_ctl_waitq, thread->t_flags & SVC_STOPPED);
1067
1068         /*
1069          * unregister transaction callbacks only when sync thread
1070          * has finished operations with llog
1071          */
1072         osp_sync_id_traction_fini(d);
1073
1074         RETURN(0);
1075 }
1076
1077 static DEFINE_MUTEX(osp_id_tracker_sem);
1078 static CFS_LIST_HEAD(osp_id_tracker_list);
1079
1080 static void osp_sync_tracker_commit_cb(struct thandle *th, void *cookie)
1081 {
1082         struct osp_id_tracker   *tr = cookie;
1083         struct osp_device       *d;
1084         struct osp_txn_info     *txn;
1085
1086         LASSERT(tr);
1087
1088         txn = osp_txn_info(&th->th_ctx);
1089         if (txn == NULL || txn->oti_current_id < tr->otr_committed_id)
1090                 return;
1091
1092         spin_lock(&tr->otr_lock);
1093         if (likely(txn->oti_current_id > tr->otr_committed_id)) {
1094                 CDEBUG(D_OTHER, "committed: %u -> %u\n",
1095                        tr->otr_committed_id, txn->oti_current_id);
1096                 tr->otr_committed_id = txn->oti_current_id;
1097
1098                 cfs_list_for_each_entry(d, &tr->otr_wakeup_list,
1099                                         opd_syn_ontrack) {
1100                         d->opd_syn_last_committed_id = tr->otr_committed_id;
1101                         wake_up(&d->opd_syn_waitq);
1102                 }
1103         }
1104         spin_unlock(&tr->otr_lock);
1105 }
1106
1107 static int osp_sync_id_traction_init(struct osp_device *d)
1108 {
1109         struct osp_id_tracker   *tr, *found = NULL;
1110         int                      rc = 0;
1111
1112         LASSERT(d);
1113         LASSERT(d->opd_storage);
1114         LASSERT(d->opd_syn_tracker == NULL);
1115         CFS_INIT_LIST_HEAD(&d->opd_syn_ontrack);
1116
1117         mutex_lock(&osp_id_tracker_sem);
1118         cfs_list_for_each_entry(tr, &osp_id_tracker_list, otr_list) {
1119                 if (tr->otr_dev == d->opd_storage) {
1120                         LASSERT(cfs_atomic_read(&tr->otr_refcount));
1121                         cfs_atomic_inc(&tr->otr_refcount);
1122                         d->opd_syn_tracker = tr;
1123                         found = tr;
1124                         break;
1125                 }
1126         }
1127
1128         if (found == NULL) {
1129                 rc = -ENOMEM;
1130                 OBD_ALLOC_PTR(tr);
1131                 if (tr) {
1132                         d->opd_syn_tracker = tr;
1133                         spin_lock_init(&tr->otr_lock);
1134                         tr->otr_dev = d->opd_storage;
1135                         tr->otr_next_id = 1;
1136                         tr->otr_committed_id = 0;
1137                         cfs_atomic_set(&tr->otr_refcount, 1);
1138                         CFS_INIT_LIST_HEAD(&tr->otr_wakeup_list);
1139                         cfs_list_add(&tr->otr_list, &osp_id_tracker_list);
1140                         tr->otr_tx_cb.dtc_txn_commit =
1141                                                 osp_sync_tracker_commit_cb;
1142                         tr->otr_tx_cb.dtc_cookie = tr;
1143                         tr->otr_tx_cb.dtc_tag = LCT_MD_THREAD;
1144                         dt_txn_callback_add(d->opd_storage, &tr->otr_tx_cb);
1145                         rc = 0;
1146                 }
1147         }
1148         mutex_unlock(&osp_id_tracker_sem);
1149
1150         return rc;
1151 }
1152
1153 static void osp_sync_id_traction_fini(struct osp_device *d)
1154 {
1155         struct osp_id_tracker *tr;
1156
1157         ENTRY;
1158
1159         LASSERT(d);
1160         tr = d->opd_syn_tracker;
1161         if (tr == NULL) {
1162                 EXIT;
1163                 return;
1164         }
1165
1166         osp_sync_remove_from_tracker(d);
1167
1168         mutex_lock(&osp_id_tracker_sem);
1169         if (cfs_atomic_dec_and_test(&tr->otr_refcount)) {
1170                 dt_txn_callback_del(d->opd_storage, &tr->otr_tx_cb);
1171                 LASSERT(cfs_list_empty(&tr->otr_wakeup_list));
1172                 cfs_list_del(&tr->otr_list);
1173                 OBD_FREE_PTR(tr);
1174                 d->opd_syn_tracker = NULL;
1175         }
1176         mutex_unlock(&osp_id_tracker_sem);
1177
1178         EXIT;
1179 }
1180
1181 /*
1182  * generates id for the tracker
1183  */
1184 static __u32 osp_sync_id_get(struct osp_device *d, __u32 id)
1185 {
1186         struct osp_id_tracker *tr;
1187
1188         tr = d->opd_syn_tracker;
1189         LASSERT(tr);
1190
1191         /* XXX: we can improve this introducing per-cpu preallocated ids? */
1192         spin_lock(&tr->otr_lock);
1193         if (unlikely(tr->otr_next_id <= d->opd_syn_last_used_id)) {
1194                 spin_unlock(&tr->otr_lock);
1195                 CERROR("%s: next %u, last synced %lu\n",
1196                        d->opd_obd->obd_name, tr->otr_next_id,
1197                        d->opd_syn_last_used_id);
1198                 LBUG();
1199         }
1200
1201         if (id == 0)
1202                 id = tr->otr_next_id++;
1203         if (id > d->opd_syn_last_used_id)
1204                 d->opd_syn_last_used_id = id;
1205         if (cfs_list_empty(&d->opd_syn_ontrack))
1206                 cfs_list_add(&d->opd_syn_ontrack, &tr->otr_wakeup_list);
1207         spin_unlock(&tr->otr_lock);
1208         CDEBUG(D_OTHER, "new id %u\n", (unsigned) id);
1209
1210         return id;
1211 }
1212
1213 static void osp_sync_remove_from_tracker(struct osp_device *d)
1214 {
1215         struct osp_id_tracker *tr;
1216
1217         tr = d->opd_syn_tracker;
1218         LASSERT(tr);
1219
1220         if (cfs_list_empty(&d->opd_syn_ontrack))
1221                 return;
1222
1223         spin_lock(&tr->otr_lock);
1224         cfs_list_del_init(&d->opd_syn_ontrack);
1225         spin_unlock(&tr->otr_lock);
1226 }
1227