lustre/ldlm/ldlm_resource.c

   1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
   2  * vim:expandtab:shiftwidth=8:tabstop=8:
   3  *
   4  * Copyright (C) 2002, 2003 Cluster File Systems, Inc.
   5  *   Author: Phil Schwan <phil@clusterfs.com>
   6  *   Author: Peter Braam <braam@clusterfs.com>
   7  *
   8  *   This file is part of Lustre, http://www.lustre.org.
   9  *
  10  *   Lustre is free software; you can redistribute it and/or
  11  *   modify it under the terms of version 2 of the GNU General Public
  12  *   License as published by the Free Software Foundation.
  13  *
  14  *   Lustre is distributed in the hope that it will be useful,
  15  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  *   GNU General Public License for more details.
  18  *
  19  *   You should have received a copy of the GNU General Public License
  20  *   along with Lustre; if not, write to the Free Software
  21  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  22  */
  23
  24 #define DEBUG_SUBSYSTEM S_LDLM
  25 #ifdef __KERNEL__
  26 # include <linux/lustre_dlm.h>
  27 #else
  28 # include <liblustre.h>
  29 #endif
  30
  31 #include <linux/obd_class.h>
  32 #include "ldlm_internal.h"
  33
  34 kmem_cache_t *ldlm_resource_slab, *ldlm_lock_slab;
  35
  36 DECLARE_MUTEX(ldlm_namespace_lock);
  37 struct list_head ldlm_namespace_list = LIST_HEAD_INIT(ldlm_namespace_list);
  38 struct proc_dir_entry *ldlm_type_proc_dir = NULL;
  39 struct proc_dir_entry *ldlm_ns_proc_dir = NULL;
  40 struct proc_dir_entry *ldlm_svc_proc_dir = NULL;
  41
  42 #ifdef LPROCFS
  43 static int ldlm_proc_dump_ns(struct file *file, const char *buffer,
  44                              unsigned long count, void *data)
  45 {
  46         ldlm_dump_all_namespaces(D_DLMTRACE);
  47         RETURN(count);
  48 }
  49
  50 int ldlm_proc_setup(void)
  51 {
  52         int rc;
  53         struct lprocfs_vars list[] = {
  54                 { "dump_namespaces", NULL, ldlm_proc_dump_ns, NULL },
  55                 { NULL }};
  56         ENTRY;
  57         LASSERT(ldlm_ns_proc_dir == NULL);
  58
  59         ldlm_type_proc_dir = lprocfs_register(OBD_LDLM_DEVICENAME,
  60                                               proc_lustre_root,
  61                                               NULL, NULL);
  62         if (IS_ERR(ldlm_type_proc_dir)) {
  63                 CERROR("LProcFS failed in ldlm-init\n");
  64                 rc = PTR_ERR(ldlm_type_proc_dir);
  65                 GOTO(err, rc);
  66         }
  67
  68         ldlm_ns_proc_dir = lprocfs_register("namespaces",
  69                                             ldlm_type_proc_dir,
  70                                             NULL, NULL);
  71         if (IS_ERR(ldlm_ns_proc_dir)) {
  72                 CERROR("LProcFS failed in ldlm-init\n");
  73                 rc = PTR_ERR(ldlm_ns_proc_dir);
  74                 GOTO(err_type, rc);
  75         }
  76
  77         ldlm_svc_proc_dir = lprocfs_register("services",
  78                                             ldlm_type_proc_dir,
  79                                             NULL, NULL);
  80         if (IS_ERR(ldlm_svc_proc_dir)) {
  81                 CERROR("LProcFS failed in ldlm-init\n");
  82                 rc = PTR_ERR(ldlm_svc_proc_dir);
  83                 GOTO(err_ns, rc);
  84         }
  85
  86         rc = lprocfs_add_vars(ldlm_type_proc_dir, list, NULL);
  87
  88         RETURN(0);
  89
  90 err_ns:
  91         lprocfs_remove(ldlm_ns_proc_dir);
  92 err_type:
  93         lprocfs_remove(ldlm_type_proc_dir);
  94 err:
  95         ldlm_type_proc_dir = NULL;
  96         ldlm_ns_proc_dir = NULL;
  97         ldlm_svc_proc_dir = NULL;
  98         RETURN(rc);
  99 }
 100
 101 void ldlm_proc_cleanup(void)
 102 {
 103         if (ldlm_svc_proc_dir) {
 104                 lprocfs_remove(ldlm_svc_proc_dir);
 105                 ldlm_svc_proc_dir = NULL;
 106         }
 107
 108         if (ldlm_ns_proc_dir) {
 109                 lprocfs_remove(ldlm_ns_proc_dir);
 110                 ldlm_ns_proc_dir = NULL;
 111         }
 112
 113         if (ldlm_type_proc_dir) {
 114                 lprocfs_remove(ldlm_type_proc_dir);
 115                 ldlm_type_proc_dir = NULL;
 116         }
 117 }
 118
 119 static int lprocfs_uint_rd(char *page, char **start, off_t off,
 120                            int count, int *eof, void *data)
 121 {
 122         unsigned int *temp = (unsigned int *)data;
 123         return snprintf(page, count, "%u\n", *temp);
 124 }
 125
 126 static int lprocfs_read_lru_size(char *page, char **start, off_t off,
 127                                  int count, int *eof, void *data)
 128 {
 129         struct ldlm_namespace *ns = data;
 130         return lprocfs_uint_rd(page, start, off, count, eof,
 131                                &ns->ns_max_unused);
 132 }
 133
 134 #define MAX_STRING_SIZE 128
 135 static int lprocfs_write_lru_size(struct file *file, const char *buffer,
 136                                   unsigned long count, void *data)
 137 {
 138         struct ldlm_namespace *ns = data;
 139         char dummy[MAX_STRING_SIZE + 1], *end;
 140         unsigned long tmp;
 141
 142         dummy[MAX_STRING_SIZE] = '\0';
 143         copy_from_user(dummy, buffer, MAX_STRING_SIZE);
 144
 145         if (count == 6 && memcmp(dummy, "clear", 5) == 0) {
 146                 CDEBUG(D_DLMTRACE,
 147                        "dropping all unused locks from namespace %s\n",
 148                        ns->ns_name);
 149                 tmp = ns->ns_max_unused;
 150                 ns->ns_max_unused = 0;
 151                 ldlm_cancel_lru(ns, LDLM_SYNC);
 152                 ns->ns_max_unused = tmp;
 153                 return count;
 154         }
 155
 156         tmp = simple_strtoul(dummy, &end, 0);
 157         if (tmp == 0 && *end) {
 158                 CERROR("invalid value written\n");
 159                 return -EINVAL;
 160         }
 161
 162         CDEBUG(D_DLMTRACE, "changing namespace %s max_unused from %u to %u\n",
 163                ns->ns_name, ns->ns_max_unused, (unsigned int)tmp);
 164         ns->ns_max_unused = (unsigned int)tmp;
 165
 166         ldlm_cancel_lru(ns, LDLM_ASYNC);
 167
 168         return count;
 169 }
 170
 171 void ldlm_proc_namespace(struct ldlm_namespace *ns)
 172 {
 173         struct lprocfs_vars lock_vars[2];
 174         char lock_name[MAX_STRING_SIZE + 1];
 175
 176         LASSERT(ns != NULL);
 177         LASSERT(ns->ns_name != NULL);
 178
 179         lock_name[MAX_STRING_SIZE] = '\0';
 180
 181         memset(lock_vars, 0, sizeof(lock_vars));
 182         lock_vars[0].name = lock_name;
 183
 184         snprintf(lock_name, MAX_STRING_SIZE, "%s/resource_count", ns->ns_name);
 185         lock_vars[0].data = &ns->ns_refcount;
 186         lock_vars[0].read_fptr = lprocfs_rd_atomic;
 187         lprocfs_add_vars(ldlm_ns_proc_dir, lock_vars, 0);
 188
 189         snprintf(lock_name, MAX_STRING_SIZE, "%s/lock_count", ns->ns_name);
 190         lock_vars[0].data = &ns->ns_locks;
 191         lock_vars[0].read_fptr = lprocfs_rd_u64;
 192         lprocfs_add_vars(ldlm_ns_proc_dir, lock_vars, 0);
 193
 194         if (ns->ns_client) {
 195                 snprintf(lock_name, MAX_STRING_SIZE, "%s/lock_unused_count",
 196                          ns->ns_name);
 197                 lock_vars[0].data = &ns->ns_nr_unused;
 198                 lock_vars[0].read_fptr = lprocfs_uint_rd;
 199                 lprocfs_add_vars(ldlm_ns_proc_dir, lock_vars, 0);
 200
 201                 snprintf(lock_name, MAX_STRING_SIZE, "%s/lru_size",
 202                          ns->ns_name);
 203                 lock_vars[0].data = ns;
 204                 lock_vars[0].read_fptr = lprocfs_read_lru_size;
 205                 lock_vars[0].write_fptr = lprocfs_write_lru_size;
 206                 lprocfs_add_vars(ldlm_ns_proc_dir, lock_vars, 0);
 207         }
 208 }
 209 #undef MAX_STRING_SIZE
 210 #else
 211 #define ldlm_proc_namespace(ns) do {} while (0)
 212 #endif /* LPROCFS */
 213
 214 struct ldlm_namespace *ldlm_namespace_new(char *name, __u32 client)
 215 {
 216         struct ldlm_namespace *ns = NULL;
 217         struct list_head *bucket;
 218         int rc;
 219         ENTRY;
 220
 221         rc = ldlm_get_ref();
 222         if (rc) {
 223                 CERROR("ldlm_get_ref failed: %d\n", rc);
 224                 RETURN(NULL);
 225         }
 226
 227         OBD_ALLOC(ns, sizeof(*ns));
 228         if (!ns)
 229                 GOTO(out_ref, NULL);
 230
 231         OBD_VMALLOC(ns->ns_hash, sizeof(*ns->ns_hash) * RES_HASH_SIZE);
 232         if (!ns->ns_hash)
 233                 GOTO(out_ns, NULL);
 234
 235         OBD_ALLOC(ns->ns_name, strlen(name) + 1);
 236         if (!ns->ns_name)
 237                 GOTO(out_hash, NULL);
 238
 239         strcpy(ns->ns_name, name);
 240
 241         INIT_LIST_HEAD(&ns->ns_root_list);
 242         l_lock_init(&ns->ns_lock);
 243         init_waitqueue_head(&ns->ns_refcount_waitq);
 244         atomic_set(&ns->ns_refcount, 0);
 245         ns->ns_client = client;
 246         spin_lock_init(&ns->ns_counter_lock);
 247         ns->ns_locks = 0;
 248
 249         for (bucket = ns->ns_hash + RES_HASH_SIZE - 1; bucket >= ns->ns_hash;
 250              bucket--)
 251                 INIT_LIST_HEAD(bucket);
 252
 253         INIT_LIST_HEAD(&ns->ns_unused_list);
 254         ns->ns_nr_unused = 0;
 255         ns->ns_max_unused = LDLM_DEFAULT_LRU_SIZE;
 256
 257         down(&ldlm_namespace_lock);
 258         list_add(&ns->ns_list_chain, &ldlm_namespace_list);
 259         up(&ldlm_namespace_lock);
 260         ldlm_proc_namespace(ns);
 261         RETURN(ns);
 262
 263 out_hash:
 264         POISON(ns->ns_hash, 0x5a, sizeof(*ns->ns_hash) * RES_HASH_SIZE);
 265         OBD_VFREE(ns->ns_hash, sizeof(*ns->ns_hash) * RES_HASH_SIZE);
 266 out_ns:
 267         OBD_FREE(ns, sizeof(*ns));
 268 out_ref:
 269         ldlm_put_ref(0);
 270         RETURN(NULL);
 271 }
 272
 273 extern struct ldlm_lock *ldlm_lock_get(struct ldlm_lock *lock);
 274
 275 /* If flags contains FL_LOCAL_ONLY, don't try to tell the server, just cleanup.
 276  * This is currently only used for recovery, and we make certain assumptions
 277  * as a result--notably, that we shouldn't cancel locks with refs. -phil
 278  *
 279  * Called with the ns_lock held. */
 280 static void cleanup_resource(struct ldlm_resource *res, struct list_head *q,
 281                              int flags)
 282 {
 283         struct list_head *tmp, *pos;
 284         int rc = 0, client = res->lr_namespace->ns_client;
 285         int local_only = (flags & LDLM_FL_LOCAL_ONLY);
 286         ENTRY;
 287
 288         list_for_each_safe(tmp, pos, q) {
 289                 struct ldlm_lock *lock;
 290                 lock = list_entry(tmp, struct ldlm_lock, l_res_link);
 291                 LDLM_LOCK_GET(lock);
 292
 293                 /* Set CBPENDING so nothing in the cancellation path
 294                  * can match this lock */
 295                 lock->l_flags |= LDLM_FL_CBPENDING;
 296                 lock->l_flags |= LDLM_FL_FAILED;
 297                 lock->l_flags |= flags;
 298
 299                 if (local_only && (lock->l_readers || lock->l_writers)) {
 300                         /* This is a little bit gross, but much better than the
 301                          * alternative: pretend that we got a blocking AST from
 302                          * the server, so that when the lock is decref'd, it
 303                          * will go away ... */
 304                         /* ... without sending a CANCEL message. */
 305                         lock->l_flags |= LDLM_FL_LOCAL_ONLY;
 306                         LDLM_DEBUG(lock, "setting FL_LOCAL_ONLY");
 307                         if (lock->l_completion_ast)
 308                                 lock->l_completion_ast(lock, 0, NULL);
 309                         LDLM_LOCK_PUT(lock);
 310                         continue;
 311                 }
 312
 313                 if (client) {
 314                         struct lustre_handle lockh;
 315                         ldlm_lock2handle(lock, &lockh);
 316                         if (!local_only) {
 317                                 rc = ldlm_cli_cancel(&lockh);
 318                                 if (rc)
 319                                         CERROR("ldlm_cli_cancel: %d\n", rc);
 320                         }
 321                         /* Force local cleanup on errors, too. */
 322                         if (local_only || rc != ELDLM_OK)
 323                                 ldlm_lock_cancel(lock);
 324                 } else {
 325                         LDLM_DEBUG(lock, "Freeing a lock still held by a "
 326                                    "client node");
 327
 328                         ldlm_resource_unlink_lock(lock);
 329                         ldlm_lock_destroy(lock);
 330                 }
 331                 LDLM_LOCK_PUT(lock);
 332         }
 333         EXIT;
 334 }
 335
 336 int ldlm_namespace_cleanup(struct ldlm_namespace *ns, int flags)
 337 {
 338         int i;
 339
 340         if (ns == NULL) {
 341                 CDEBUG(D_INFO, "NULL ns, skipping cleanup\n");
 342                 return ELDLM_OK;
 343         }
 344
 345         l_lock(&ns->ns_lock);
 346         for (i = 0; i < RES_HASH_SIZE; i++) {
 347                 struct list_head *tmp, *pos;
 348                 list_for_each_safe(tmp, pos, &(ns->ns_hash[i])) {
 349                         struct ldlm_resource *res;
 350                         res = list_entry(tmp, struct ldlm_resource, lr_hash);
 351                         ldlm_resource_getref(res);
 352
 353                         cleanup_resource(res, &res->lr_granted, flags);
 354                         cleanup_resource(res, &res->lr_converting, flags);
 355                         cleanup_resource(res, &res->lr_waiting, flags);
 356
 357                         if (!ldlm_resource_putref(res)) {
 358                                 CERROR("Namespace %s resource refcount %d "
 359                                        "after lock cleanup\n",
 360                                        ns->ns_name,
 361                                        atomic_read(&res->lr_refcount));
 362                         }
 363                 }
 364         }
 365         l_unlock(&ns->ns_lock);
 366
 367         return ELDLM_OK;
 368 }
 369
 370 /* Cleanup, but also free, the namespace */
 371 int ldlm_namespace_free(struct ldlm_namespace *ns, int force)
 372 {
 373         if (!ns)
 374                 RETURN(ELDLM_OK);
 375
 376         down(&ldlm_namespace_lock);
 377         list_del(&ns->ns_list_chain);
 378         up(&ldlm_namespace_lock);
 379
 380         /* At shutdown time, don't call the cancellation callback */
 381         ldlm_namespace_cleanup(ns, 0);
 382
 383 #ifdef LPROCFS
 384         {
 385                 struct proc_dir_entry *dir;
 386                 dir = lprocfs_srch(ldlm_ns_proc_dir, ns->ns_name);
 387                 if (dir == NULL) {
 388                         CERROR("dlm namespace %s has no procfs dir?\n",
 389                                ns->ns_name);
 390                 } else {
 391                         lprocfs_remove(dir);
 392                 }
 393         }
 394 #endif
 395
 396         if (atomic_read(&ns->ns_refcount) > 0) {
 397                 struct l_wait_info lwi = LWI_INTR(NULL, NULL);
 398                 int rc;
 399                 CDEBUG(D_DLMTRACE,
 400                        "dlm namespace %s free waiting on refcount %d\n",
 401                        ns->ns_name, atomic_read(&ns->ns_refcount));
 402                 rc = l_wait_event(ns->ns_refcount_waitq,
 403                                   atomic_read(&ns->ns_refcount) == 0, &lwi);
 404                 if (atomic_read(&ns->ns_refcount)) {
 405                         LCONSOLE_ERROR("Lock manager: wait for %s namespace "
 406                                        "cleanup aborted with %d resources in "
 407                                        "use. (%d)\nI'm going to try to clean "
 408                                        "up anyway, but I might need a reboot "
 409                                        "of this node.\n", ns->ns_name,
 410                                        atomic_read(&ns->ns_refcount), rc);
 411                 }
 412                 CDEBUG(D_DLMTRACE,
 413                        "dlm namespace %s free done waiting\n", ns->ns_name);
 414         }
 415
 416         POISON(ns->ns_hash, 0x5a, sizeof(*ns->ns_hash) * RES_HASH_SIZE);
 417         OBD_VFREE(ns->ns_hash, sizeof(*ns->ns_hash) * RES_HASH_SIZE);
 418         OBD_FREE(ns->ns_name, strlen(ns->ns_name) + 1);
 419         OBD_FREE(ns, sizeof(*ns));
 420
 421         ldlm_put_ref(force);
 422
 423         return ELDLM_OK;
 424 }
 425
 426 static __u32 ldlm_hash_fn(struct ldlm_resource *parent, struct ldlm_res_id name)
 427 {
 428         __u32 hash = 0;
 429         int i;
 430
 431         for (i = 0; i < RES_NAME_SIZE; i++)
 432                 hash += name.name[i];
 433
 434         hash += (__u32)((unsigned long)parent >> 4);
 435
 436         return (hash & RES_HASH_MASK);
 437 }
 438
 439 static struct ldlm_resource *ldlm_resource_new(void)
 440 {
 441         struct ldlm_resource *res;
 442
 443         OBD_SLAB_ALLOC(res, ldlm_resource_slab, SLAB_NOFS, sizeof *res);
 444         if (res == NULL)
 445                 return NULL;
 446
 447         memset(res, 0, sizeof(*res));
 448
 449         INIT_LIST_HEAD(&res->lr_children);
 450         INIT_LIST_HEAD(&res->lr_childof);
 451         INIT_LIST_HEAD(&res->lr_granted);
 452         INIT_LIST_HEAD(&res->lr_converting);
 453         INIT_LIST_HEAD(&res->lr_waiting);
 454         sema_init(&res->lr_lvb_sem, 1);
 455         atomic_set(&res->lr_refcount, 1);
 456
 457         return res;
 458 }
 459
 460 /* Args: locked namespace
 461  * Returns: newly-allocated, referenced, unlocked resource */
 462 static struct ldlm_resource *
 463 ldlm_resource_add(struct ldlm_namespace *ns, struct ldlm_resource *parent,
 464                   struct ldlm_res_id name, ldlm_type_t type)
 465 {
 466         struct list_head *bucket;
 467         struct ldlm_resource *res;
 468         ENTRY;
 469
 470         LASSERTF(type >= LDLM_MIN_TYPE && type < LDLM_MAX_TYPE,
 471                  "type: %d\n", type);
 472
 473         res = ldlm_resource_new();
 474         if (!res)
 475                 RETURN(NULL);
 476
 477         l_lock(&ns->ns_lock);
 478         memcpy(&res->lr_name, &name, sizeof(res->lr_name));
 479         res->lr_namespace = ns;
 480         atomic_inc(&ns->ns_refcount);
 481
 482         res->lr_type = type;
 483         res->lr_most_restr = LCK_NL;
 484
 485         bucket = ns->ns_hash + ldlm_hash_fn(parent, name);
 486         list_add(&res->lr_hash, bucket);
 487
 488         if (parent == NULL) {
 489                 list_add(&res->lr_childof, &ns->ns_root_list);
 490         } else {
 491                 res->lr_parent = parent;
 492                 list_add(&res->lr_childof, &parent->lr_children);
 493         }
 494         l_unlock(&ns->ns_lock);
 495
 496
 497         RETURN(res);
 498 }
 499
 500 /* Args: unlocked namespace
 501  * Locks: takes and releases ns->ns_lock and res->lr_lock
 502  * Returns: referenced, unlocked ldlm_resource or NULL */
 503 struct ldlm_resource *
 504 ldlm_resource_get(struct ldlm_namespace *ns, struct ldlm_resource *parent,
 505                   struct ldlm_res_id name, ldlm_type_t type, int create)
 506 {
 507         struct list_head *bucket, *tmp;
 508         struct ldlm_resource *res = NULL;
 509         ENTRY;
 510
 511         LASSERT(ns != NULL);
 512         LASSERT(ns->ns_hash != NULL);
 513         LASSERT(name.name[0] != 0);
 514
 515         l_lock(&ns->ns_lock);
 516         bucket = ns->ns_hash + ldlm_hash_fn(parent, name);
 517
 518         list_for_each(tmp, bucket) {
 519                 res = list_entry(tmp, struct ldlm_resource, lr_hash);
 520
 521                 if (memcmp(&res->lr_name, &name, sizeof(res->lr_name)) == 0) {
 522                         ldlm_resource_getref(res);
 523                         l_unlock(&ns->ns_lock);
 524                         RETURN(res);
 525                 }
 526         }
 527
 528         if (create) {
 529                 res = ldlm_resource_add(ns, parent, name, type);
 530                 if (res == NULL)
 531                         GOTO(out, NULL);
 532         } else {
 533                 res = NULL;
 534         }
 535
 536         if (create && ns->ns_lvbo && ns->ns_lvbo->lvbo_init) {
 537                 int rc;
 538
 539                 /* Although this is technically a lock inversion risk (lvb_sem
 540                  * should be taken before DLM lock), this resource was just
 541                  * created, so nobody else can take the lvb_sem yet. -p */
 542                 down(&res->lr_lvb_sem);
 543                 /* Drop the dlm lock, because lvbo_init can touch the disk */
 544                 l_unlock(&ns->ns_lock);
 545                 OBD_FAIL_TIMEOUT(OBD_FAIL_LDLM_CREATE_RESOURCE, 2);
 546                 rc = ns->ns_lvbo->lvbo_init(res);
 547                 up(&res->lr_lvb_sem);
 548                 if (rc)
 549                         CERROR("lvbo_init failed for resource "LPU64"/"LPU64
 550                                ": rc %d\n", name.name[0], name.name[1], rc);
 551         } else {
 552 out:
 553                 l_unlock(&ns->ns_lock);
 554         }
 555
 556         RETURN(res);
 557 }
 558
 559 struct ldlm_resource *ldlm_resource_getref(struct ldlm_resource *res)
 560 {
 561         LASSERT(res != NULL);
 562         LASSERT(res != LP_POISON);
 563         atomic_inc(&res->lr_refcount);
 564         CDEBUG(D_DLMTRACE, "getref res: %p count: %d\n", res,
 565                atomic_read(&res->lr_refcount));
 566         return res;
 567 }
 568
 569 /* Returns 1 if the resource was freed, 0 if it remains. */
 570 int ldlm_resource_putref(struct ldlm_resource *res)
 571 {
 572         int rc = 0;
 573         ENTRY;
 574
 575         CDEBUG(D_DLMTRACE, "putref res: %p count: %d\n", res,
 576                atomic_read(&res->lr_refcount) - 1);
 577         LASSERT(atomic_read(&res->lr_refcount) > 0);
 578         LASSERT(atomic_read(&res->lr_refcount) < LI_POISON);
 579
 580         if (atomic_dec_and_test(&res->lr_refcount)) {
 581                 struct ldlm_namespace *ns = res->lr_namespace;
 582                 ENTRY;
 583
 584                 l_lock(&ns->ns_lock);
 585
 586                 if (atomic_read(&res->lr_refcount) != 0) {
 587                         /* We lost the race. */
 588                         l_unlock(&ns->ns_lock);
 589                         RETURN(rc);
 590                 }
 591
 592                 if (!list_empty(&res->lr_granted)) {
 593                         ldlm_resource_dump(D_ERROR, res);
 594                         LBUG();
 595                 }
 596
 597                 if (!list_empty(&res->lr_converting)) {
 598                         ldlm_resource_dump(D_ERROR, res);
 599                         LBUG();
 600                 }
 601
 602                 if (!list_empty(&res->lr_waiting)) {
 603                         ldlm_resource_dump(D_ERROR, res);
 604                         LBUG();
 605                 }
 606
 607                 if (!list_empty(&res->lr_children)) {
 608                         ldlm_resource_dump(D_ERROR, res);
 609                         LBUG();
 610                 }
 611
 612                 list_del_init(&res->lr_hash);
 613                 list_del_init(&res->lr_childof);
 614                 if (res->lr_lvb_data)
 615                         OBD_FREE(res->lr_lvb_data, res->lr_lvb_len);
 616                 l_unlock(&ns->ns_lock);
 617
 618                 OBD_SLAB_FREE(res, ldlm_resource_slab, sizeof *res);
 619
 620                 if (atomic_dec_and_test(&ns->ns_refcount)) {
 621                         CDEBUG(D_DLMTRACE, "last ref on ns %s\n", ns->ns_name);
 622                         wake_up(&ns->ns_refcount_waitq);
 623                 }
 624
 625                 rc = 1;
 626                 EXIT;
 627         }
 628
 629         RETURN(rc);
 630 }
 631
 632 void ldlm_resource_add_lock(struct ldlm_resource *res, struct list_head *head,
 633                             struct ldlm_lock *lock)
 634 {
 635         l_lock(&res->lr_namespace->ns_lock);
 636
 637         ldlm_resource_dump(D_OTHER, res);
 638         CDEBUG(D_OTHER, "About to add this lock:\n");
 639         ldlm_lock_dump(D_OTHER, lock, 0);
 640
 641         if (lock->l_destroyed) {
 642                 CDEBUG(D_OTHER, "Lock destroyed, not adding to resource\n");
 643                 goto out;
 644         }
 645
 646         LASSERT(list_empty(&lock->l_res_link));
 647
 648         list_add_tail(&lock->l_res_link, head);
 649  out:
 650         l_unlock(&res->lr_namespace->ns_lock);
 651 }
 652
 653 void ldlm_resource_unlink_lock(struct ldlm_lock *lock)
 654 {
 655         l_lock(&lock->l_resource->lr_namespace->ns_lock);
 656         list_del_init(&lock->l_res_link);
 657         l_unlock(&lock->l_resource->lr_namespace->ns_lock);
 658 }
 659
 660 void ldlm_res2desc(struct ldlm_resource *res, struct ldlm_resource_desc *desc)
 661 {
 662         desc->lr_type = res->lr_type;
 663         memcpy(&desc->lr_name, &res->lr_name, sizeof(desc->lr_name));
 664 }
 665
 666 void ldlm_dump_all_namespaces(int level)
 667 {
 668         struct list_head *tmp;
 669
 670         down(&ldlm_namespace_lock);
 671
 672         list_for_each(tmp, &ldlm_namespace_list) {
 673                 struct ldlm_namespace *ns;
 674                 ns = list_entry(tmp, struct ldlm_namespace, ns_list_chain);
 675                 ldlm_namespace_dump(level, ns);
 676         }
 677
 678         up(&ldlm_namespace_lock);
 679 }
 680
 681 void ldlm_namespace_dump(int level, struct ldlm_namespace *ns)
 682 {
 683         struct list_head *tmp;
 684
 685         CDEBUG(level, "--- Namespace: %s (rc: %d, client: %d)\n", ns->ns_name,
 686                atomic_read(&ns->ns_refcount), ns->ns_client);
 687
 688         l_lock(&ns->ns_lock);
 689         if (time_after(jiffies, ns->ns_next_dump)) {
 690                 list_for_each(tmp, &ns->ns_root_list) {
 691                         struct ldlm_resource *res;
 692                         res = list_entry(tmp, struct ldlm_resource, lr_childof);
 693
 694                         /* Once we have resources with children, this should
 695                          * really dump them recursively. */
 696                         ldlm_resource_dump(level, res);
 697                 }
 698                 ns->ns_next_dump = jiffies + 10 * HZ;
 699         }
 700         l_unlock(&ns->ns_lock);
 701 }
 702
 703 void ldlm_resource_dump(int level, struct ldlm_resource *res)
 704 {
 705         struct list_head *tmp;
 706         int pos;
 707
 708         if (RES_NAME_SIZE != 4)
 709                 LBUG();
 710
 711         CDEBUG(level, "--- Resource: %p ("LPU64"/"LPU64"/"LPU64"/"LPU64
 712                ") (rc: %d)\n", res, res->lr_name.name[0], res->lr_name.name[1],
 713                res->lr_name.name[2], res->lr_name.name[3],
 714                atomic_read(&res->lr_refcount));
 715
 716         if (!list_empty(&res->lr_granted)) {
 717                 pos = 0;
 718                 CDEBUG(level, "Granted locks:\n");
 719                 list_for_each(tmp, &res->lr_granted) {
 720                         struct ldlm_lock *lock;
 721                         lock = list_entry(tmp, struct ldlm_lock, l_res_link);
 722                         ldlm_lock_dump(level, lock, ++pos);
 723                 }
 724         }
 725         if (!list_empty(&res->lr_converting)) {
 726                 pos = 0;
 727                 CDEBUG(level, "Converting locks:\n");
 728                 list_for_each(tmp, &res->lr_converting) {
 729                         struct ldlm_lock *lock;
 730                         lock = list_entry(tmp, struct ldlm_lock, l_res_link);
 731                         ldlm_lock_dump(level, lock, ++pos);
 732                 }
 733         }
 734         if (!list_empty(&res->lr_waiting)) {
 735                 pos = 0;
 736                 CDEBUG(level, "Waiting locks:\n");
 737                 list_for_each(tmp, &res->lr_waiting) {
 738                         struct ldlm_lock *lock;
 739                         lock = list_entry(tmp, struct ldlm_lock, l_res_link);
 740                         ldlm_lock_dump(level, lock, ++pos);
 741                 }
 742         }
 743 }