lustre/ptlrpc/recov_thread.c

   1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
   2  * vim:expandtab:shiftwidth=8:tabstop=8:
   3  *
   4  *  Copyright (C) 2003 Cluster File Systems, Inc.
   5  *   Author: Andreas Dilger <adilger@clusterfs.com>
   6  *
   7  *   This file is part of the Lustre file system, http://www.lustre.org
   8  *   Lustre is a trademark of Cluster File Systems, Inc.
   9  *
  10  *   You may have signed or agreed to another license before downloading
  11  *   this software.  If so, you are bound by the terms and conditions
  12  *   of that agreement, and the following does not apply to you.  See the
  13  *   LICENSE file included with this distribution for more information.
  14  *
  15  *   If you did not agree to a different license, then this copy of Lustre
  16  *   is open source software; you can redistribute it and/or modify it
  17  *   under the terms of version 2 of the GNU General Public License as
  18  *   published by the Free Software Foundation.
  19  *
  20  *   In either case, Lustre is distributed in the hope that it will be
  21  *   useful, but WITHOUT ANY WARRANTY; without even the implied warranty
  22  *   of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  23  *   license text for more details.
  24  *
  25  * OST<->MDS recovery logging thread.
  26  *
  27  * Invariants in implementation:
  28  * - we do not share logs among different OST<->MDS connections, so that
  29  *   if an OST or MDS fails it need only look at log(s) relevant to itself
  30  */
  31
  32 #define DEBUG_SUBSYSTEM S_LOG
  33
  34 #ifndef EXPORT_SYMTAB
  35 # define EXPORT_SYMTAB
  36 #endif
  37
  38 #ifdef __KERNEL__
  39 # include <libcfs/libcfs.h>
  40 #else
  41 # include <libcfs/list.h>
  42 # include <liblustre.h>
  43 #endif
  44
  45 #include <obd_class.h>
  46 #include <lustre_commit_confd.h>
  47 #include <obd_support.h>
  48 #include <obd_class.h>
  49 #include <lustre_net.h>
  50 #include <lnet/types.h>
  51 #include <libcfs/list.h>
  52 #include <lustre_log.h>
  53 #include "ptlrpc_internal.h"
  54
  55 #ifdef __KERNEL__
  56
  57 /* Allocate new commit structs in case we do not have enough.
  58  * Make the llcd size small enough that it fits into a single page when we
  59  * are sending/receiving it. */
  60 static int llcd_alloc(struct llog_commit_master *lcm)
  61 {
  62         struct llog_canceld_ctxt *llcd;
  63         int llcd_size;
  64
  65         /* payload of lustre_msg V2 is bigger */
  66         llcd_size = 4096 - lustre_msg_size(LUSTRE_MSG_MAGIC_V2, 1, NULL);
  67         OBD_ALLOC(llcd,
  68                   llcd_size + offsetof(struct llog_canceld_ctxt, llcd_cookies));
  69         if (llcd == NULL)
  70                 return -ENOMEM;
  71
  72         llcd->llcd_size = llcd_size;
  73         llcd->llcd_lcm = lcm;
  74
  75         spin_lock(&lcm->lcm_llcd_lock);
  76         list_add(&llcd->llcd_list, &lcm->lcm_llcd_free);
  77         atomic_inc(&lcm->lcm_llcd_numfree);
  78         spin_unlock(&lcm->lcm_llcd_lock);
  79
  80         return 0;
  81 }
  82
  83 /* Get a free cookie struct from the list */
  84 static struct llog_canceld_ctxt *llcd_grab(struct llog_commit_master *lcm)
  85 {
  86         struct llog_canceld_ctxt *llcd;
  87
  88 repeat:
  89         spin_lock(&lcm->lcm_llcd_lock);
  90         if (list_empty(&lcm->lcm_llcd_free)) {
  91                 spin_unlock(&lcm->lcm_llcd_lock);
  92                 if (llcd_alloc(lcm) < 0) {
  93                         CERROR("unable to allocate log commit data!\n");
  94                         return NULL;
  95                 }
  96                 /* check new llcd wasn't grabbed while lock dropped, b=7407 */
  97                 goto repeat;
  98         }
  99
 100         llcd = list_entry(lcm->lcm_llcd_free.next, typeof(*llcd), llcd_list);
 101         list_del(&llcd->llcd_list);
 102         atomic_dec(&lcm->lcm_llcd_numfree);
 103         spin_unlock(&lcm->lcm_llcd_lock);
 104
 105         llcd->llcd_cookiebytes = 0;
 106
 107         return llcd;
 108 }
 109
 110 static void llcd_put(struct llog_canceld_ctxt *llcd)
 111 {
 112         struct llog_commit_master *lcm = llcd->llcd_lcm;
 113
 114         llog_ctxt_put(llcd->llcd_ctxt);
 115         if (atomic_read(&lcm->lcm_llcd_numfree) >= lcm->lcm_llcd_maxfree) {
 116                 int llcd_size = llcd->llcd_size +
 117                          offsetof(struct llog_canceld_ctxt, llcd_cookies);
 118                 OBD_FREE(llcd, llcd_size);
 119         } else {
 120                 spin_lock(&lcm->lcm_llcd_lock);
 121                 list_add(&llcd->llcd_list, &lcm->lcm_llcd_free);
 122                 atomic_inc(&lcm->lcm_llcd_numfree);
 123                 spin_unlock(&lcm->lcm_llcd_lock);
 124         }
 125 }
 126
 127 /* Send some cookies to the appropriate target */
 128 static void llcd_send(struct llog_canceld_ctxt *llcd)
 129 {
 130         if (!(llcd->llcd_lcm->lcm_flags & LLOG_LCM_FL_EXIT)) {
 131                 spin_lock(&llcd->llcd_lcm->lcm_llcd_lock);
 132                 list_add_tail(&llcd->llcd_list,
 133                               &llcd->llcd_lcm->lcm_llcd_pending);
 134                 spin_unlock(&llcd->llcd_lcm->lcm_llcd_lock);
 135         }
 136         cfs_waitq_signal_nr(&llcd->llcd_lcm->lcm_waitq, 1);
 137 }
 138
 139 /**
 140  * Grab llcd and assign it to passed @ctxt. Also set up backward link
 141  * and get ref on @ctxt.
 142  */
 143 static struct llog_canceld_ctxt *ctxt_llcd_grab(struct llog_ctxt *ctxt)
 144 {
 145         struct llog_canceld_ctxt *llcd;
 146
 147         LASSERT_SEM_LOCKED(&ctxt->loc_sem);
 148         llcd = llcd_grab(ctxt->loc_lcm);
 149         if (llcd == NULL)
 150                 return NULL;
 151
 152         llcd->llcd_ctxt = llog_ctxt_get(ctxt);
 153         ctxt->loc_llcd = llcd;
 154
 155         CDEBUG(D_RPCTRACE,"grab llcd %p:%p\n", ctxt->loc_llcd, ctxt);
 156         return llcd;
 157 }
 158
 159 /**
 160  * Put llcd in passed @ctxt. Set ->loc_llcd to NULL.
 161  */
 162 static void ctxt_llcd_put(struct llog_ctxt *ctxt)
 163 {
 164         mutex_down(&ctxt->loc_sem);
 165         if (ctxt->loc_llcd != NULL) {
 166                 CDEBUG(D_RPCTRACE,"put llcd %p:%p\n", ctxt->loc_llcd, ctxt);
 167                 llcd_put(ctxt->loc_llcd);
 168                 ctxt->loc_llcd = NULL;
 169         }
 170         ctxt->loc_imp = NULL;
 171         mutex_up(&ctxt->loc_sem);
 172 }
 173
 174 /* deleted objects have a commit callback that cancels the MDS
 175  * log record for the deletion.  The commit callback calls this
 176  * function
 177  */
 178 int llog_obd_repl_cancel(struct llog_ctxt *ctxt,
 179                          struct lov_stripe_md *lsm, int count,
 180                          struct llog_cookie *cookies, int flags)
 181 {
 182         struct llog_canceld_ctxt *llcd;
 183         int rc = 0;
 184         ENTRY;
 185
 186         LASSERT(ctxt);
 187
 188         mutex_down(&ctxt->loc_sem);
 189         llcd = ctxt->loc_llcd;
 190
 191         if (ctxt->loc_imp == NULL) {
 192                 CDEBUG(D_RPCTRACE, "no import for ctxt %p\n", ctxt);
 193                 GOTO(out, rc = 0);
 194         }
 195
 196         if (count > 0 && cookies != NULL) {
 197                 if (llcd == NULL) {
 198                         llcd = ctxt_llcd_grab(ctxt);
 199                         if (llcd == NULL) {
 200                                 CERROR("couldn't get an llcd - dropped "LPX64
 201                                        ":%x+%u\n",
 202                                        cookies->lgc_lgl.lgl_oid,
 203                                        cookies->lgc_lgl.lgl_ogen,
 204                                        cookies->lgc_index);
 205                                 GOTO(out, rc = -ENOMEM);
 206                         }
 207                 }
 208
 209                 memcpy((char *)llcd->llcd_cookies + llcd->llcd_cookiebytes,
 210                        cookies, sizeof(*cookies));
 211                 llcd->llcd_cookiebytes += sizeof(*cookies);
 212         } else {
 213                 if (llcd == NULL || !(flags & OBD_LLOG_FL_SENDNOW))
 214                         GOTO(out, rc);
 215         }
 216
 217         if ((llcd->llcd_size - llcd->llcd_cookiebytes) < sizeof(*cookies) ||
 218             (flags & OBD_LLOG_FL_SENDNOW)) {
 219                 CDEBUG(D_RPCTRACE, "send llcd %p:%p\n", llcd, llcd->llcd_ctxt);
 220                 ctxt->loc_llcd = NULL;
 221                 llcd_send(llcd);
 222         }
 223 out:
 224         mutex_up(&ctxt->loc_sem);
 225         return rc;
 226 }
 227 EXPORT_SYMBOL(llog_obd_repl_cancel);
 228
 229 int llog_obd_repl_sync(struct llog_ctxt *ctxt, struct obd_export *exp)
 230 {
 231         int rc = 0;
 232         ENTRY;
 233
 234         if (exp && (ctxt->loc_imp == exp->exp_imp_reverse)) {
 235                 CDEBUG(D_RPCTRACE,"reverse import disconnect\n");
 236                 /*
 237                  * We put llcd because it is not going to sending list and
 238                  * thus, its refc will not be handled. We will handle it here.
 239                  */
 240                 ctxt_llcd_put(ctxt);
 241         } else {
 242                 /*
 243                  * Sending cancel. This means that ctxt->loc_llcd wil be
 244                  * put on sending list in llog_obd_repl_cancel() and in
 245                  * this case recovery thread will take care of it refc.
 246                  */
 247                 rc = llog_cancel(ctxt, NULL, 0, NULL, OBD_LLOG_FL_SENDNOW);
 248         }
 249         RETURN(rc);
 250 }
 251 EXPORT_SYMBOL(llog_obd_repl_sync);
 252
 253 static inline void stop_log_commit(struct llog_commit_master *lcm,
 254                                    struct llog_commit_daemon *lcd,
 255                                    int rc)
 256 {
 257         CERROR("error preparing commit: rc %d\n", rc);
 258
 259         spin_lock(&lcm->lcm_llcd_lock);
 260         list_splice_init(&lcd->lcd_llcd_list, &lcm->lcm_llcd_resend);
 261         spin_unlock(&lcm->lcm_llcd_lock);
 262 }
 263
 264 static int log_commit_thread(void *arg)
 265 {
 266         struct llog_commit_master *lcm = arg;
 267         struct llog_commit_daemon *lcd;
 268         struct llog_canceld_ctxt *llcd, *n;
 269         struct obd_import *import = NULL;
 270         ENTRY;
 271
 272         OBD_ALLOC(lcd, sizeof(*lcd));
 273         if (lcd == NULL)
 274                 RETURN(-ENOMEM);
 275
 276         spin_lock(&lcm->lcm_thread_lock);
 277         THREAD_NAME(cfs_curproc_comm(), CFS_CURPROC_COMM_MAX - 1,
 278                     "ll_log_comt_%02d", atomic_read(&lcm->lcm_thread_total));
 279         atomic_inc(&lcm->lcm_thread_total);
 280         spin_unlock(&lcm->lcm_thread_lock);
 281
 282         ptlrpc_daemonize(cfs_curproc_comm()); /* thread never needs to do IO */
 283
 284         CFS_INIT_LIST_HEAD(&lcd->lcd_lcm_list);
 285         CFS_INIT_LIST_HEAD(&lcd->lcd_llcd_list);
 286         lcd->lcd_lcm = lcm;
 287
 288         CDEBUG(D_HA, "%s started\n", cfs_curproc_comm());
 289         do {
 290                 struct ptlrpc_request *request;
 291                 struct list_head *sending_list;
 292                 int rc = 0;
 293
 294                 if (import)
 295                         class_import_put(import);
 296                 import = NULL;
 297
 298                 /* If we do not have enough pages available, allocate some */
 299                 while (atomic_read(&lcm->lcm_llcd_numfree) <
 300                        lcm->lcm_llcd_minfree) {
 301                         if (llcd_alloc(lcm) < 0)
 302                                 break;
 303                 }
 304
 305                 spin_lock(&lcm->lcm_thread_lock);
 306                 atomic_inc(&lcm->lcm_thread_numidle);
 307                 list_move(&lcd->lcd_lcm_list, &lcm->lcm_thread_idle);
 308                 spin_unlock(&lcm->lcm_thread_lock);
 309
 310                 wait_event_interruptible(lcm->lcm_waitq,
 311                                          !list_empty(&lcm->lcm_llcd_pending) ||
 312                                          lcm->lcm_flags & LLOG_LCM_FL_EXIT);
 313
 314                 /* If we are the last available thread, start a new one in case
 315                  * we get blocked on an RPC (nobody else will start a new one)*/
 316                 spin_lock(&lcm->lcm_thread_lock);
 317                 atomic_dec(&lcm->lcm_thread_numidle);
 318                 list_move(&lcd->lcd_lcm_list, &lcm->lcm_thread_busy);
 319                 spin_unlock(&lcm->lcm_thread_lock);
 320
 321                 sending_list = &lcm->lcm_llcd_pending;
 322         resend:
 323                 if (import)
 324                         class_import_put(import);
 325                 import = NULL;
 326                 if (lcm->lcm_flags & LLOG_LCM_FL_EXIT) {
 327                         lcm->lcm_llcd_maxfree = 0;
 328                         lcm->lcm_llcd_minfree = 0;
 329                         lcm->lcm_thread_max = 0;
 330
 331                         if (list_empty(&lcm->lcm_llcd_pending) ||
 332                             lcm->lcm_flags & LLOG_LCM_FL_EXIT_FORCE)
 333                                 break;
 334                 }
 335
 336                 if (atomic_read(&lcm->lcm_thread_numidle) <= 1 &&
 337                     atomic_read(&lcm->lcm_thread_total) < lcm->lcm_thread_max) {
 338                         rc = llog_start_commit_thread(lcm);
 339                         if (rc < 0)
 340                                 CERROR("error starting thread: rc %d\n", rc);
 341                 }
 342
 343                 /* Move all of the pending cancels from the same OST off of
 344                  * the list, so we don't get multiple threads blocked and/or
 345                  * doing upcalls on the same OST in case of failure. */
 346                 spin_lock(&lcm->lcm_llcd_lock);
 347                 if (!list_empty(sending_list)) {
 348                         list_move_tail(sending_list->next,
 349                                        &lcd->lcd_llcd_list);
 350                         llcd = list_entry(lcd->lcd_llcd_list.next,
 351                                           typeof(*llcd), llcd_list);
 352                         LASSERT(llcd->llcd_lcm == lcm);
 353                         import = llcd->llcd_ctxt->loc_imp;
 354                         if (import)
 355                                 class_import_get(import);
 356                 }
 357                 list_for_each_entry_safe(llcd, n, sending_list, llcd_list) {
 358                         LASSERT(llcd->llcd_lcm == lcm);
 359                         if (import == llcd->llcd_ctxt->loc_imp)
 360                                 list_move_tail(&llcd->llcd_list,
 361                                                &lcd->lcd_llcd_list);
 362                 }
 363                 if (sending_list != &lcm->lcm_llcd_resend) {
 364                         list_for_each_entry_safe(llcd, n, &lcm->lcm_llcd_resend,
 365                                                  llcd_list) {
 366                                 LASSERT(llcd->llcd_lcm == lcm);
 367                                 if (import == llcd->llcd_ctxt->loc_imp)
 368                                         list_move_tail(&llcd->llcd_list,
 369                                                        &lcd->lcd_llcd_list);
 370                         }
 371                 }
 372                 spin_unlock(&lcm->lcm_llcd_lock);
 373
 374                 /* We are the only one manipulating our local list - no lock */
 375                 list_for_each_entry_safe(llcd,n, &lcd->lcd_llcd_list,llcd_list){
 376                         char *bufs[2] = { NULL, (char *)llcd->llcd_cookies };
 377
 378                         list_del(&llcd->llcd_list);
 379                         if (llcd->llcd_cookiebytes == 0) {
 380                                 CDEBUG(D_RPCTRACE, "put empty llcd %p:%p\n",
 381                                        llcd, llcd->llcd_ctxt);
 382                                 llcd_put(llcd);
 383                                 continue;
 384                         }
 385
 386                         mutex_down(&llcd->llcd_ctxt->loc_sem);
 387                         if (llcd->llcd_ctxt->loc_imp == NULL) {
 388                                 mutex_up(&llcd->llcd_ctxt->loc_sem);
 389                                 CWARN("import will be destroyed, put "
 390                                       "llcd %p:%p\n", llcd, llcd->llcd_ctxt);
 391                                 llcd_put(llcd);
 392                                 continue;
 393                         }
 394                         mutex_up(&llcd->llcd_ctxt->loc_sem);
 395
 396                         if (!import || (import == LP_POISON) ||
 397                             (import->imp_client == LP_POISON)) {
 398                                 CERROR("No import %p (llcd=%p, ctxt=%p)\n",
 399                                        import, llcd, llcd->llcd_ctxt);
 400                                 llcd_put(llcd);
 401                                 continue;
 402                         }
 403
 404                         OBD_FAIL_TIMEOUT(OBD_FAIL_PTLRPC_DELAY_RECOV, 10);
 405
 406                         request = ptlrpc_request_alloc(import, &RQF_LOG_CANCEL);
 407                         if (request == NULL) {
 408                                 rc = -ENOMEM;
 409                                 stop_log_commit(lcm, lcd, rc);
 410                                 break;
 411                         }
 412
 413                         req_capsule_set_size(&request->rq_pill, &RMF_LOGCOOKIES,
 414                                              RCL_CLIENT,llcd->llcd_cookiebytes);
 415
 416                         rc = ptlrpc_request_bufs_pack(request,
 417                                                       LUSTRE_LOG_VERSION,
 418                                                       OBD_LOG_CANCEL, bufs,
 419                                                       NULL);
 420                         if (rc) {
 421                                 ptlrpc_request_free(request);
 422                                 stop_log_commit(lcm, lcd, rc);
 423                                 break;
 424                         }
 425
 426                         /* XXX FIXME bug 249, 5515 */
 427                         request->rq_request_portal = LDLM_CANCEL_REQUEST_PORTAL;
 428                         request->rq_reply_portal = LDLM_CANCEL_REPLY_PORTAL;
 429
 430                         ptlrpc_request_set_replen(request);
 431                         mutex_down(&llcd->llcd_ctxt->loc_sem);
 432                         if (llcd->llcd_ctxt->loc_imp == NULL) {
 433                                 mutex_up(&llcd->llcd_ctxt->loc_sem);
 434                                 CWARN("import will be destroyed, put "
 435                                       "llcd %p:%p\n", llcd, llcd->llcd_ctxt);
 436                                 llcd_put(llcd);
 437                                 ptlrpc_req_finished(request);
 438                                 continue;
 439                         }
 440                         mutex_up(&llcd->llcd_ctxt->loc_sem);
 441                         rc = ptlrpc_queue_wait(request);
 442                         ptlrpc_req_finished(request);
 443
 444                         /* If the RPC failed, we put this and the remaining
 445                          * messages onto the resend list for another time. */
 446                         if (rc == 0) {
 447                                 llcd_put(llcd);
 448                                 continue;
 449                         }
 450
 451                         CERROR("commit %p:%p drop %d cookies: rc %d\n",
 452                                llcd, llcd->llcd_ctxt,
 453                                (int)(llcd->llcd_cookiebytes /
 454                                      sizeof(*llcd->llcd_cookies)), rc);
 455                         llcd_put(llcd);
 456                 }
 457
 458                 if (rc == 0) {
 459                         sending_list = &lcm->lcm_llcd_resend;
 460                         if (!list_empty(sending_list))
 461                                 goto resend;
 462                 }
 463         } while(1);
 464
 465         if (import)
 466                 class_import_put(import);
 467
 468         /* If we are force exiting, just drop all of the cookies. */
 469         if (lcm->lcm_flags & LLOG_LCM_FL_EXIT_FORCE) {
 470                 spin_lock(&lcm->lcm_llcd_lock);
 471                 list_splice_init(&lcm->lcm_llcd_pending, &lcd->lcd_llcd_list);
 472                 list_splice_init(&lcm->lcm_llcd_resend, &lcd->lcd_llcd_list);
 473                 list_splice_init(&lcm->lcm_llcd_free, &lcd->lcd_llcd_list);
 474                 spin_unlock(&lcm->lcm_llcd_lock);
 475
 476                 list_for_each_entry_safe(llcd, n, &lcd->lcd_llcd_list,llcd_list)
 477                         llcd_put(llcd);
 478         }
 479
 480         spin_lock(&lcm->lcm_thread_lock);
 481         list_del(&lcd->lcd_lcm_list);
 482         spin_unlock(&lcm->lcm_thread_lock);
 483         OBD_FREE(lcd, sizeof(*lcd));
 484
 485         CDEBUG(D_HA, "%s exiting\n", cfs_curproc_comm());
 486
 487         spin_lock(&lcm->lcm_thread_lock);
 488         atomic_dec(&lcm->lcm_thread_total);
 489         spin_unlock(&lcm->lcm_thread_lock);
 490         cfs_waitq_signal(&lcm->lcm_waitq);
 491
 492         return 0;
 493 }
 494
 495 int llog_start_commit_thread(struct llog_commit_master *lcm)
 496 {
 497         int rc;
 498         ENTRY;
 499
 500         if (atomic_read(&lcm->lcm_thread_total) >= lcm->lcm_thread_max)
 501                 RETURN(0);
 502
 503         rc = cfs_kernel_thread(log_commit_thread, lcm, CLONE_VM | CLONE_FILES);
 504         if (rc < 0) {
 505                 CERROR("error starting thread #%d: %d\n",
 506                        atomic_read(&lcm->lcm_thread_total), rc);
 507                 RETURN(rc);
 508         }
 509
 510         RETURN(0);
 511 }
 512 EXPORT_SYMBOL(llog_start_commit_thread);
 513
 514 static struct llog_process_args {
 515         struct semaphore         llpa_sem;
 516         struct llog_ctxt        *llpa_ctxt;
 517         void                    *llpa_cb;
 518         void                    *llpa_arg;
 519 } llpa;
 520
 521 int llog_init_commit_master(struct llog_commit_master *lcm)
 522 {
 523         CFS_INIT_LIST_HEAD(&lcm->lcm_thread_busy);
 524         CFS_INIT_LIST_HEAD(&lcm->lcm_thread_idle);
 525         spin_lock_init(&lcm->lcm_thread_lock);
 526         atomic_set(&lcm->lcm_thread_numidle, 0);
 527         cfs_waitq_init(&lcm->lcm_waitq);
 528         CFS_INIT_LIST_HEAD(&lcm->lcm_llcd_pending);
 529         CFS_INIT_LIST_HEAD(&lcm->lcm_llcd_resend);
 530         CFS_INIT_LIST_HEAD(&lcm->lcm_llcd_free);
 531         spin_lock_init(&lcm->lcm_llcd_lock);
 532         atomic_set(&lcm->lcm_llcd_numfree, 0);
 533         lcm->lcm_llcd_minfree = 0;
 534         lcm->lcm_thread_max = 5;
 535         /* FIXME initialize semaphore for llog_process_args */
 536         sema_init(&llpa.llpa_sem, 1);
 537         return 0;
 538 }
 539 EXPORT_SYMBOL(llog_init_commit_master);
 540
 541 int llog_cleanup_commit_master(struct llog_commit_master *lcm,
 542                                int force)
 543 {
 544         lcm->lcm_flags |= LLOG_LCM_FL_EXIT;
 545         if (force)
 546                 lcm->lcm_flags |= LLOG_LCM_FL_EXIT_FORCE;
 547         cfs_waitq_signal(&lcm->lcm_waitq);
 548
 549         wait_event_interruptible(lcm->lcm_waitq,
 550                                  atomic_read(&lcm->lcm_thread_total) == 0);
 551         return 0;
 552 }
 553 EXPORT_SYMBOL(llog_cleanup_commit_master);
 554
 555 static int log_process_thread(void *args)
 556 {
 557         struct llog_process_args *data = args;
 558         struct llog_ctxt *ctxt = data->llpa_ctxt;
 559         void   *cb = data->llpa_cb;
 560         struct llog_logid logid = *(struct llog_logid *)(data->llpa_arg);
 561         struct llog_handle *llh = NULL;
 562         int rc;
 563         ENTRY;
 564
 565         mutex_up(&data->llpa_sem);
 566         ptlrpc_daemonize("llog_process");     /* thread does IO to log files */
 567
 568         rc = llog_create(ctxt, &llh, &logid, NULL);
 569         if (rc) {
 570                 CERROR("llog_create failed %d\n", rc);
 571                 GOTO(out, rc);
 572         }
 573         rc = llog_init_handle(llh, LLOG_F_IS_CAT, NULL);
 574         if (rc) {
 575                 CERROR("llog_init_handle failed %d\n", rc);
 576                 GOTO(release_llh, rc);
 577         }
 578
 579         if (cb) {
 580                 rc = llog_cat_process(llh, (llog_cb_t)cb, NULL);
 581                 if (rc != LLOG_PROC_BREAK)
 582                         CERROR("llog_cat_process failed %d\n", rc);
 583         } else {
 584                 CWARN("no callback function for recovery\n");
 585         }
 586
 587         CDEBUG(D_HA, "send llcd %p:%p forcibly after recovery\n",
 588                ctxt->loc_llcd, ctxt);
 589         llog_sync(ctxt, NULL);
 590
 591 release_llh:
 592         rc = llog_cat_put(llh);
 593         if (rc)
 594                 CERROR("llog_cat_put failed %d\n", rc);
 595 out:
 596         llog_ctxt_put(ctxt);
 597         RETURN(rc);
 598 }
 599
 600 static int llog_recovery_generic(struct llog_ctxt *ctxt, void *handle,void *arg)
 601 {
 602         struct obd_device *obd = ctxt->loc_obd;
 603         int rc;
 604         ENTRY;
 605
 606         if (obd->obd_stopping)
 607                 RETURN(-ENODEV);
 608
 609         mutex_down(&llpa.llpa_sem);
 610         llpa.llpa_cb = handle;
 611         llpa.llpa_arg = arg;
 612         llpa.llpa_ctxt = llog_ctxt_get(ctxt);
 613         if (!llpa.llpa_ctxt) {
 614                 up(&llpa.llpa_sem);
 615                 RETURN(-ENODEV);
 616         }
 617         rc = cfs_kernel_thread(log_process_thread, &llpa, CLONE_VM | CLONE_FILES);
 618         if (rc < 0) {
 619                 llog_ctxt_put(ctxt);
 620                 CERROR("error starting log_process_thread: %d\n", rc);
 621         } else {
 622                 CDEBUG(D_HA, "log_process_thread: %d\n", rc);
 623                 rc = 0;
 624         }
 625
 626         RETURN(rc);
 627 }
 628
 629 int llog_repl_connect(struct llog_ctxt *ctxt, int count,
 630                       struct llog_logid *logid, struct llog_gen *gen,
 631                       struct obd_uuid *uuid)
 632 {
 633         struct llog_canceld_ctxt *llcd;
 634         int rc;
 635         ENTRY;
 636
 637         /* send back llcd before recovery from llog */
 638         if (ctxt->loc_llcd != NULL) {
 639                 CWARN("llcd %p:%p not empty\n", ctxt->loc_llcd, ctxt);
 640                 llog_sync(ctxt, NULL);
 641         }
 642
 643         mutex_down(&ctxt->loc_sem);
 644         ctxt->loc_gen = *gen;
 645         llcd = ctxt_llcd_grab(ctxt);
 646         if (llcd == NULL) {
 647                 CERROR("couldn't get an llcd\n");
 648                 mutex_up(&ctxt->loc_sem);
 649                 RETURN(-ENOMEM);
 650         }
 651         mutex_up(&ctxt->loc_sem);
 652
 653         rc = llog_recovery_generic(ctxt, ctxt->llog_proc_cb, logid);
 654         if (rc != 0) {
 655                 ctxt_llcd_put(ctxt);
 656                 CERROR("error recovery process: %d\n", rc);
 657         }
 658         RETURN(rc);
 659 }
 660 EXPORT_SYMBOL(llog_repl_connect);
 661
 662 #else /* !__KERNEL__ */
 663
 664 int llog_obd_repl_cancel(struct llog_ctxt *ctxt,
 665                          struct lov_stripe_md *lsm, int count,
 666                          struct llog_cookie *cookies, int flags)
 667 {
 668         return 0;
 669 }
 670 #endif