lustre/ldlm/ldlm_resource.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.gnu.org/licenses/gpl-2.0.html
  19  *
  20  * GPL HEADER END
  21  */
  22 /*
  23  * Copyright (c) 2002, 2010, Oracle and/or its affiliates. All rights reserved.
  24  * Use is subject to license terms.
  25  *
  26  * Copyright (c) 2010, 2017, Intel Corporation.
  27  */
  28 /*
  29  * This file is part of Lustre, http://www.lustre.org/
  30  *
  31  * lustre/ldlm/ldlm_resource.c
  32  *
  33  * Author: Phil Schwan <phil@clusterfs.com>
  34  * Author: Peter Braam <braam@clusterfs.com>
  35  */
  36
  37 #define DEBUG_SUBSYSTEM S_LDLM
  38 #include <lustre_dlm.h>
  39 #include <lustre_fid.h>
  40 #include <obd_class.h>
  41 #include <libcfs/linux/linux-hash.h>
  42 #include "ldlm_internal.h"
  43
  44 struct kmem_cache *ldlm_resource_slab, *ldlm_lock_slab;
  45 struct kmem_cache *ldlm_interval_tree_slab;
  46 struct kmem_cache *ldlm_inodebits_slab;
  47
  48 int ldlm_srv_namespace_nr = 0;
  49 int ldlm_cli_namespace_nr = 0;
  50
  51 DEFINE_MUTEX(ldlm_srv_namespace_lock);
  52 LIST_HEAD(ldlm_srv_namespace_list);
  53
  54 DEFINE_MUTEX(ldlm_cli_namespace_lock);
  55 /* Client Namespaces that have active resources in them.
  56  * Once all resources go away, ldlm_poold moves such namespaces to the
  57  * inactive list */
  58 LIST_HEAD(ldlm_cli_active_namespace_list);
  59 /* Client namespaces that don't have any locks in them */
  60 LIST_HEAD(ldlm_cli_inactive_namespace_list);
  61
  62 static struct dentry *ldlm_debugfs_dir;
  63 static struct dentry *ldlm_ns_debugfs_dir;
  64 struct dentry *ldlm_svc_debugfs_dir;
  65
  66 /* during debug dump certain amount of granted locks for one resource to avoid
  67  * DDOS. */
  68 static unsigned int ldlm_dump_granted_max = 256;
  69
  70 static ssize_t ldebugfs_dump_ns_seq_write(struct file *file,
  71                                           const char __user *buffer,
  72                                           size_t count, loff_t *off)
  73 {
  74         ldlm_dump_all_namespaces(LDLM_NAMESPACE_SERVER, D_DLMTRACE);
  75         ldlm_dump_all_namespaces(LDLM_NAMESPACE_CLIENT, D_DLMTRACE);
  76         RETURN(count);
  77 }
  78
  79 LDEBUGFS_FOPS_WR_ONLY(ldlm, dump_ns);
  80
  81 static int ldlm_rw_uint_seq_show(struct seq_file *m, void *v)
  82 {
  83         seq_printf(m, "%u\n", *(unsigned int *)m->private);
  84         return 0;
  85 }
  86
  87 static ssize_t
  88 ldlm_rw_uint_seq_write(struct file *file, const char __user *buffer,
  89                        size_t count, loff_t *off)
  90 {
  91         struct seq_file *seq = file->private_data;
  92
  93         if (!count)
  94                 return 0;
  95
  96         return kstrtouint_from_user(buffer, count, 0,
  97                                     (unsigned int *)seq->private);
  98 }
  99
 100 LDEBUGFS_SEQ_FOPS(ldlm_rw_uint);
 101
 102 #ifdef HAVE_SERVER_SUPPORT
 103
 104 static int seq_watermark_show(struct seq_file *m, void *data)
 105 {
 106         seq_printf(m, "%llu\n", *(__u64 *)m->private);
 107         return 0;
 108 }
 109
 110 static ssize_t seq_watermark_write(struct file *file,
 111                                    const char __user *buffer, size_t count,
 112                                    loff_t *off)
 113 {
 114         struct seq_file *m = file->private_data;
 115         u64 value;
 116         __u64 watermark;
 117         __u64 *data = m->private;
 118         bool wm_low = (data == &ldlm_reclaim_threshold_mb) ? true : false;
 119         char kernbuf[22] = "";
 120         int rc;
 121
 122         if (count >= sizeof(kernbuf))
 123                 return -EINVAL;
 124
 125         if (copy_from_user(kernbuf, buffer, count))
 126                 return -EFAULT;
 127         kernbuf[count] = 0;
 128
 129         rc = sysfs_memparse(kernbuf, count, &value, "MiB");
 130         if (rc < 0) {
 131                 CERROR("Failed to set %s, rc = %d.\n",
 132                        wm_low ? "lock_reclaim_threshold_mb" : "lock_limit_mb",
 133                        rc);
 134                 return rc;
 135         } else if (value != 0 && value < (1 << 20)) {
 136                 CERROR("%s should be greater than 1MB.\n",
 137                        wm_low ? "lock_reclaim_threshold_mb" : "lock_limit_mb");
 138                 return -EINVAL;
 139         }
 140         watermark = value >> 20;
 141
 142         if (wm_low) {
 143                 if (ldlm_lock_limit_mb != 0 && watermark > ldlm_lock_limit_mb) {
 144                         CERROR("lock_reclaim_threshold_mb must be smaller than "
 145                                "lock_limit_mb.\n");
 146                         return -EINVAL;
 147                 }
 148
 149                 *data = watermark;
 150                 if (watermark != 0) {
 151                         watermark <<= 20;
 152                         do_div(watermark, sizeof(struct ldlm_lock));
 153                 }
 154                 ldlm_reclaim_threshold = watermark;
 155         } else {
 156                 if (ldlm_reclaim_threshold_mb != 0 &&
 157                     watermark < ldlm_reclaim_threshold_mb) {
 158                         CERROR("lock_limit_mb must be greater than "
 159                                "lock_reclaim_threshold_mb.\n");
 160                         return -EINVAL;
 161                 }
 162
 163                 *data = watermark;
 164                 if (watermark != 0) {
 165                         watermark <<= 20;
 166                         do_div(watermark, sizeof(struct ldlm_lock));
 167                 }
 168                 ldlm_lock_limit = watermark;
 169         }
 170
 171         return count;
 172 }
 173
 174 static int seq_watermark_open(struct inode *inode, struct file *file)
 175 {
 176         return single_open(file, seq_watermark_show, inode->i_private);
 177 }
 178
 179 static const struct file_operations ldlm_watermark_fops = {
 180         .owner          = THIS_MODULE,
 181         .open           = seq_watermark_open,
 182         .read           = seq_read,
 183         .write          = seq_watermark_write,
 184         .llseek         = seq_lseek,
 185         .release        = lprocfs_single_release,
 186 };
 187
 188 static int seq_granted_show(struct seq_file *m, void *data)
 189 {
 190         seq_printf(m, "%llu\n", percpu_counter_sum_positive(
 191                    (struct percpu_counter *)m->private));
 192         return 0;
 193 }
 194
 195 static int seq_granted_open(struct inode *inode, struct file *file)
 196 {
 197         return single_open(file, seq_granted_show, inode->i_private);
 198 }
 199
 200 static const struct file_operations ldlm_granted_fops = {
 201         .owner  = THIS_MODULE,
 202         .open   = seq_granted_open,
 203         .read   = seq_read,
 204         .llseek = seq_lseek,
 205         .release = seq_release,
 206 };
 207
 208 #endif /* HAVE_SERVER_SUPPORT */
 209
 210 static struct ldebugfs_vars ldlm_debugfs_list[] = {
 211         { .name =       "dump_namespaces",
 212           .fops =       &ldlm_dump_ns_fops,
 213           .proc_mode =  0222 },
 214         { .name =       "dump_granted_max",
 215           .fops =       &ldlm_rw_uint_fops,
 216           .data =       &ldlm_dump_granted_max },
 217 #ifdef HAVE_SERVER_SUPPORT
 218         { .name =       "lock_reclaim_threshold_mb",
 219           .fops =       &ldlm_watermark_fops,
 220           .data =       &ldlm_reclaim_threshold_mb },
 221         { .name =       "lock_limit_mb",
 222           .fops =       &ldlm_watermark_fops,
 223           .data =       &ldlm_lock_limit_mb },
 224         { .name =       "lock_granted_count",
 225           .fops =       &ldlm_granted_fops,
 226           .data =       &ldlm_granted_total },
 227 #endif
 228         { NULL }
 229 };
 230
 231 int ldlm_debugfs_setup(void)
 232 {
 233         ENTRY;
 234         ldlm_debugfs_dir = debugfs_create_dir(OBD_LDLM_DEVICENAME,
 235                                              debugfs_lustre_root);
 236         ldlm_ns_debugfs_dir = debugfs_create_dir("namespaces",
 237                                                  ldlm_debugfs_dir);
 238         ldlm_svc_debugfs_dir = debugfs_create_dir("services",
 239                                                   ldlm_debugfs_dir);
 240
 241         ldebugfs_add_vars(ldlm_debugfs_dir, ldlm_debugfs_list, NULL);
 242
 243         RETURN(0);
 244 }
 245
 246 void ldlm_debugfs_cleanup(void)
 247 {
 248         debugfs_remove_recursive(ldlm_debugfs_dir);
 249
 250         ldlm_svc_debugfs_dir = NULL;
 251         ldlm_ns_debugfs_dir = NULL;
 252         ldlm_debugfs_dir = NULL;
 253 }
 254
 255 static ssize_t resource_count_show(struct kobject *kobj, struct attribute *attr,
 256                                    char *buf)
 257 {
 258         struct ldlm_namespace *ns = container_of(kobj, struct ldlm_namespace,
 259                                                  ns_kobj);
 260         __u64                   res = 0;
 261         int                     i;
 262
 263         /* result is not strictly consistant */
 264         for (i = 0; i < (1 << ns->ns_bucket_bits); i++)
 265                 res += atomic_read(&ns->ns_rs_buckets[i].nsb_count);
 266         return sprintf(buf, "%lld\n", res);
 267 }
 268 LUSTRE_RO_ATTR(resource_count);
 269
 270 static ssize_t lock_count_show(struct kobject *kobj, struct attribute *attr,
 271                                char *buf)
 272 {
 273         struct ldlm_namespace *ns = container_of(kobj, struct ldlm_namespace,
 274                                                  ns_kobj);
 275         __u64                   locks;
 276
 277         locks = lprocfs_stats_collector(ns->ns_stats, LDLM_NSS_LOCKS,
 278                                         LPROCFS_FIELDS_FLAGS_SUM);
 279         return sprintf(buf, "%lld\n", locks);
 280 }
 281 LUSTRE_RO_ATTR(lock_count);
 282
 283 static ssize_t lock_unused_count_show(struct kobject *kobj,
 284                                       struct attribute *attr,
 285                                       char *buf)
 286 {
 287         struct ldlm_namespace *ns = container_of(kobj, struct ldlm_namespace,
 288                                                  ns_kobj);
 289
 290         return sprintf(buf, "%d\n", ns->ns_nr_unused);
 291 }
 292 LUSTRE_RO_ATTR(lock_unused_count);
 293
 294 static ssize_t lru_size_show(struct kobject *kobj, struct attribute *attr,
 295                              char *buf)
 296 {
 297         struct ldlm_namespace *ns = container_of(kobj, struct ldlm_namespace,
 298                                                  ns_kobj);
 299         __u32 *nr = &ns->ns_max_unused;
 300
 301         if (ns_connect_lru_resize(ns))
 302                 nr = &ns->ns_nr_unused;
 303         return sprintf(buf, "%u\n", *nr);
 304 }
 305
 306 static ssize_t lru_size_store(struct kobject *kobj, struct attribute *attr,
 307                               const char *buffer, size_t count)
 308 {
 309         struct ldlm_namespace *ns = container_of(kobj, struct ldlm_namespace,
 310                                                  ns_kobj);
 311         unsigned long tmp;
 312         int lru_resize;
 313         int err;
 314
 315         if (strncmp(buffer, "clear", 5) == 0) {
 316                 CDEBUG(D_DLMTRACE,
 317                        "dropping all unused locks from namespace %s\n",
 318                        ldlm_ns_name(ns));
 319                 /* Try to cancel all @ns_nr_unused locks. */
 320                 ldlm_cancel_lru(ns, INT_MAX, 0, LDLM_LRU_FLAG_CLEANUP);
 321                 return count;
 322         }
 323
 324         err = kstrtoul(buffer, 10, &tmp);
 325         if (err != 0) {
 326                 CERROR("lru_size: invalid value written\n");
 327                 return -EINVAL;
 328         }
 329         lru_resize = (tmp == 0);
 330
 331         if (ns_connect_lru_resize(ns)) {
 332                 if (!lru_resize)
 333                         ns->ns_max_unused = (unsigned int)tmp;
 334
 335                 if (tmp > ns->ns_nr_unused)
 336                         tmp = ns->ns_nr_unused;
 337                 tmp = ns->ns_nr_unused - tmp;
 338
 339                 CDEBUG(D_DLMTRACE,
 340                        "changing namespace %s unused locks from %u to %u\n",
 341                        ldlm_ns_name(ns), ns->ns_nr_unused,
 342                        (unsigned int)tmp);
 343
 344                 if (!lru_resize) {
 345                         CDEBUG(D_DLMTRACE,
 346                                "disable lru_resize for namespace %s\n",
 347                                ldlm_ns_name(ns));
 348                         ns->ns_connect_flags &= ~OBD_CONNECT_LRU_RESIZE;
 349                 }
 350                 ldlm_cancel_lru(ns, tmp, LCF_ASYNC, 0);
 351         } else {
 352                 CDEBUG(D_DLMTRACE,
 353                        "changing namespace %s max_unused from %u to %u\n",
 354                        ldlm_ns_name(ns), ns->ns_max_unused,
 355                        (unsigned int)tmp);
 356
 357                 /* Make sure that LRU resize was originally supported before
 358                  * turning it on here.
 359                  */
 360                 if (lru_resize &&
 361                     (ns->ns_orig_connect_flags & OBD_CONNECT_LRU_RESIZE)) {
 362                         CDEBUG(D_DLMTRACE,
 363                                "enable lru_resize for namespace %s\n",
 364                                ldlm_ns_name(ns));
 365                         ns->ns_connect_flags |= OBD_CONNECT_LRU_RESIZE;
 366                 }
 367                 ns->ns_max_unused = (unsigned int)tmp;
 368                 ldlm_cancel_lru(ns, 0, LCF_ASYNC, 0);
 369         }
 370
 371         return count;
 372 }
 373 LUSTRE_RW_ATTR(lru_size);
 374
 375 static ssize_t lru_cancel_batch_show(struct kobject *kobj,
 376                                  struct attribute *attr, char *buf)
 377 {
 378         struct ldlm_namespace *ns = container_of(kobj, struct ldlm_namespace,
 379                                                  ns_kobj);
 380
 381         return snprintf(buf, sizeof(buf) - 1, "%u\n", ns->ns_cancel_batch);
 382 }
 383
 384 static ssize_t lru_cancel_batch_store(struct kobject *kobj,
 385                                   struct attribute *attr,
 386                                   const char *buffer, size_t count)
 387 {
 388         struct ldlm_namespace *ns = container_of(kobj, struct ldlm_namespace,
 389                                                  ns_kobj);
 390         unsigned long tmp;
 391
 392         if (kstrtoul(buffer, 10, &tmp))
 393                 return -EINVAL;
 394
 395         ns->ns_cancel_batch = (unsigned int)tmp;
 396
 397         return count;
 398 }
 399 LUSTRE_RW_ATTR(lru_cancel_batch);
 400
 401 static ssize_t ns_recalc_pct_show(struct kobject *kobj,
 402                                   struct attribute *attr, char *buf)
 403 {
 404         struct ldlm_namespace *ns = container_of(kobj, struct ldlm_namespace,
 405                                                  ns_kobj);
 406
 407         return snprintf(buf, sizeof(buf) - 1, "%u\n", ns->ns_recalc_pct);
 408 }
 409
 410 static ssize_t ns_recalc_pct_store(struct kobject *kobj,
 411                                    struct attribute *attr,
 412                                    const char *buffer, size_t count)
 413 {
 414         struct ldlm_namespace *ns = container_of(kobj, struct ldlm_namespace,
 415                                                  ns_kobj);
 416         unsigned long tmp;
 417
 418         if (kstrtoul(buffer, 10, &tmp))
 419                 return -EINVAL;
 420
 421         if (tmp > 100)
 422                 return -ERANGE;
 423
 424         ns->ns_recalc_pct = (unsigned int)tmp;
 425
 426         return count;
 427 }
 428 LUSTRE_RW_ATTR(ns_recalc_pct);
 429
 430 static ssize_t lru_max_age_show(struct kobject *kobj, struct attribute *attr,
 431                                 char *buf)
 432 {
 433         struct ldlm_namespace *ns = container_of(kobj, struct ldlm_namespace,
 434                                                  ns_kobj);
 435
 436         return sprintf(buf, "%lld\n", ktime_to_ms(ns->ns_max_age));
 437 }
 438
 439 static ssize_t lru_max_age_store(struct kobject *kobj, struct attribute *attr,
 440                                  const char *buffer, size_t count)
 441 {
 442         struct ldlm_namespace *ns = container_of(kobj, struct ldlm_namespace,
 443                                                  ns_kobj);
 444         int scale = NSEC_PER_MSEC;
 445         unsigned long long tmp;
 446         char *buf;
 447
 448         /* Did the user ask in seconds or milliseconds. Default is in ms */
 449         buf = strstr(buffer, "ms");
 450         if (!buf) {
 451                 buf = strchr(buffer, 's');
 452                 if (buf)
 453                         scale = NSEC_PER_SEC;
 454         }
 455
 456         if (buf)
 457                 *buf = '\0';
 458
 459         if (kstrtoull(buffer, 10, &tmp))
 460                 return -EINVAL;
 461
 462         ns->ns_max_age = ktime_set(0, tmp * scale);
 463
 464         return count;
 465 }
 466 LUSTRE_RW_ATTR(lru_max_age);
 467
 468 static ssize_t early_lock_cancel_show(struct kobject *kobj,
 469                                       struct attribute *attr,
 470                                       char *buf)
 471 {
 472         struct ldlm_namespace *ns = container_of(kobj, struct ldlm_namespace,
 473                                                  ns_kobj);
 474
 475         return sprintf(buf, "%d\n", ns_connect_cancelset(ns));
 476 }
 477
 478 static ssize_t early_lock_cancel_store(struct kobject *kobj,
 479                                        struct attribute *attr,
 480                                        const char *buffer,
 481                                        size_t count)
 482 {
 483         struct ldlm_namespace *ns = container_of(kobj, struct ldlm_namespace,
 484                                                  ns_kobj);
 485         unsigned long supp = -1;
 486         int rc;
 487
 488         rc = kstrtoul(buffer, 10, &supp);
 489         if (rc < 0)
 490                 return rc;
 491
 492         if (supp == 0)
 493                 ns->ns_connect_flags &= ~OBD_CONNECT_CANCELSET;
 494         else if (ns->ns_orig_connect_flags & OBD_CONNECT_CANCELSET)
 495                 ns->ns_connect_flags |= OBD_CONNECT_CANCELSET;
 496         return count;
 497 }
 498 LUSTRE_RW_ATTR(early_lock_cancel);
 499
 500 static ssize_t dirty_age_limit_show(struct kobject *kobj,
 501                                     struct attribute *attr, char *buf)
 502 {
 503         struct ldlm_namespace *ns = container_of(kobj, struct ldlm_namespace,
 504                                                  ns_kobj);
 505
 506         return scnprintf(buf, PAGE_SIZE, "%llu\n",
 507                          ktime_divns(ns->ns_dirty_age_limit, NSEC_PER_SEC));
 508 }
 509
 510 static ssize_t dirty_age_limit_store(struct kobject *kobj,
 511                                      struct attribute *attr,
 512                                      const char *buffer, size_t count)
 513 {
 514         struct ldlm_namespace *ns = container_of(kobj, struct ldlm_namespace,
 515                                                  ns_kobj);
 516         unsigned long long tmp;
 517
 518         if (kstrtoull(buffer, 10, &tmp))
 519                 return -EINVAL;
 520
 521         ns->ns_dirty_age_limit = ktime_set(tmp, 0);
 522
 523         return count;
 524 }
 525 LUSTRE_RW_ATTR(dirty_age_limit);
 526
 527 #ifdef HAVE_SERVER_SUPPORT
 528 static ssize_t ctime_age_limit_show(struct kobject *kobj,
 529                                     struct attribute *attr, char *buf)
 530 {
 531         struct ldlm_namespace *ns = container_of(kobj, struct ldlm_namespace,
 532                                                  ns_kobj);
 533
 534         return scnprintf(buf, PAGE_SIZE, "%u\n", ns->ns_ctime_age_limit);
 535 }
 536
 537 static ssize_t ctime_age_limit_store(struct kobject *kobj,
 538                                      struct attribute *attr,
 539                                      const char *buffer, size_t count)
 540 {
 541         struct ldlm_namespace *ns = container_of(kobj, struct ldlm_namespace,
 542                                                  ns_kobj);
 543         unsigned long tmp;
 544
 545         if (kstrtoul(buffer, 10, &tmp))
 546                 return -EINVAL;
 547
 548         ns->ns_ctime_age_limit = tmp;
 549
 550         return count;
 551 }
 552 LUSTRE_RW_ATTR(ctime_age_limit);
 553
 554 static ssize_t lock_timeouts_show(struct kobject *kobj, struct attribute *attr,
 555                                   char *buf)
 556 {
 557         struct ldlm_namespace *ns = container_of(kobj, struct ldlm_namespace,
 558                                                  ns_kobj);
 559
 560         return sprintf(buf, "%d\n", ns->ns_timeouts);
 561 }
 562 LUSTRE_RO_ATTR(lock_timeouts);
 563
 564 static ssize_t max_nolock_bytes_show(struct kobject *kobj,
 565                                      struct attribute *attr, char *buf)
 566 {
 567         struct ldlm_namespace *ns = container_of(kobj, struct ldlm_namespace,
 568                                                  ns_kobj);
 569
 570         return sprintf(buf, "%u\n", ns->ns_max_nolock_size);
 571 }
 572
 573 static ssize_t max_nolock_bytes_store(struct kobject *kobj,
 574                                       struct attribute *attr,
 575                                       const char *buffer, size_t count)
 576 {
 577         struct ldlm_namespace *ns = container_of(kobj, struct ldlm_namespace,
 578                                                  ns_kobj);
 579         unsigned long tmp;
 580         int err;
 581
 582         err = kstrtoul(buffer, 10, &tmp);
 583         if (err != 0)
 584                 return -EINVAL;
 585
 586         ns->ns_max_nolock_size = tmp;
 587
 588         return count;
 589 }
 590 LUSTRE_RW_ATTR(max_nolock_bytes);
 591
 592 static ssize_t contention_seconds_show(struct kobject *kobj,
 593                                        struct attribute *attr, char *buf)
 594 {
 595         struct ldlm_namespace *ns = container_of(kobj, struct ldlm_namespace,
 596                                                  ns_kobj);
 597
 598         return scnprintf(buf, PAGE_SIZE, "%d\n", ns->ns_contention_time);
 599 }
 600
 601 static ssize_t contention_seconds_store(struct kobject *kobj,
 602                                         struct attribute *attr,
 603                                         const char *buffer, size_t count)
 604 {
 605         struct ldlm_namespace *ns = container_of(kobj, struct ldlm_namespace,
 606                                                  ns_kobj);
 607         unsigned int tmp;
 608
 609         if (kstrtouint(buffer, 10, &tmp))
 610                 return -EINVAL;
 611
 612         ns->ns_contention_time = tmp;
 613
 614         return count;
 615 }
 616 LUSTRE_RW_ATTR(contention_seconds);
 617
 618 static ssize_t contended_locks_show(struct kobject *kobj,
 619                                     struct attribute *attr, char *buf)
 620 {
 621         struct ldlm_namespace *ns = container_of(kobj, struct ldlm_namespace,
 622                                                  ns_kobj);
 623
 624         return sprintf(buf, "%u\n", ns->ns_contended_locks);
 625 }
 626
 627 static ssize_t contended_locks_store(struct kobject *kobj,
 628                                      struct attribute *attr,
 629                                      const char *buffer, size_t count)
 630 {
 631         struct ldlm_namespace *ns = container_of(kobj, struct ldlm_namespace,
 632                                                  ns_kobj);
 633         unsigned long tmp;
 634         int err;
 635
 636         err = kstrtoul(buffer, 10, &tmp);
 637         if (err != 0)
 638                 return -EINVAL;
 639
 640         ns->ns_contended_locks = tmp;
 641
 642         return count;
 643 }
 644 LUSTRE_RW_ATTR(contended_locks);
 645
 646 static ssize_t max_parallel_ast_show(struct kobject *kobj,
 647                                      struct attribute *attr, char *buf)
 648 {
 649         struct ldlm_namespace *ns = container_of(kobj, struct ldlm_namespace,
 650                                                  ns_kobj);
 651
 652         return sprintf(buf, "%u\n", ns->ns_max_parallel_ast);
 653 }
 654
 655 static ssize_t max_parallel_ast_store(struct kobject *kobj,
 656                                       struct attribute *attr,
 657                                       const char *buffer, size_t count)
 658 {
 659         struct ldlm_namespace *ns = container_of(kobj, struct ldlm_namespace,
 660                                                  ns_kobj);
 661         unsigned long tmp;
 662         int err;
 663
 664         err = kstrtoul(buffer, 10, &tmp);
 665         if (err != 0)
 666                 return -EINVAL;
 667
 668         ns->ns_max_parallel_ast = tmp;
 669
 670         return count;
 671 }
 672 LUSTRE_RW_ATTR(max_parallel_ast);
 673
 674 #endif /* HAVE_SERVER_SUPPORT */
 675
 676 /* These are for namespaces in /sys/fs/lustre/ldlm/namespaces/ */
 677 static struct attribute *ldlm_ns_attrs[] = {
 678         &lustre_attr_resource_count.attr,
 679         &lustre_attr_lock_count.attr,
 680         &lustre_attr_lock_unused_count.attr,
 681         &lustre_attr_ns_recalc_pct.attr,
 682         &lustre_attr_lru_size.attr,
 683         &lustre_attr_lru_cancel_batch.attr,
 684         &lustre_attr_lru_max_age.attr,
 685         &lustre_attr_early_lock_cancel.attr,
 686         &lustre_attr_dirty_age_limit.attr,
 687 #ifdef HAVE_SERVER_SUPPORT
 688         &lustre_attr_ctime_age_limit.attr,
 689         &lustre_attr_lock_timeouts.attr,
 690         &lustre_attr_max_nolock_bytes.attr,
 691         &lustre_attr_contention_seconds.attr,
 692         &lustre_attr_contended_locks.attr,
 693         &lustre_attr_max_parallel_ast.attr,
 694 #endif
 695         NULL,
 696 };
 697
 698 static void ldlm_ns_release(struct kobject *kobj)
 699 {
 700         struct ldlm_namespace *ns = container_of(kobj, struct ldlm_namespace,
 701                                                  ns_kobj);
 702         complete(&ns->ns_kobj_unregister);
 703 }
 704
 705 static struct kobj_type ldlm_ns_ktype = {
 706         .default_attrs  = ldlm_ns_attrs,
 707         .sysfs_ops      = &lustre_sysfs_ops,
 708         .release        = ldlm_ns_release,
 709 };
 710
 711 static void ldlm_namespace_debugfs_unregister(struct ldlm_namespace *ns)
 712 {
 713         if (IS_ERR_OR_NULL(ns->ns_debugfs_entry))
 714                 CERROR("dlm namespace %s has no procfs dir?\n",
 715                        ldlm_ns_name(ns));
 716         else
 717                 debugfs_remove_recursive(ns->ns_debugfs_entry);
 718
 719         if (ns->ns_stats != NULL)
 720                 lprocfs_free_stats(&ns->ns_stats);
 721 }
 722
 723 void ldlm_namespace_sysfs_unregister(struct ldlm_namespace *ns)
 724 {
 725         kobject_put(&ns->ns_kobj);
 726         wait_for_completion(&ns->ns_kobj_unregister);
 727 }
 728
 729 int ldlm_namespace_sysfs_register(struct ldlm_namespace *ns)
 730 {
 731         int err;
 732
 733         ns->ns_kobj.kset = ldlm_ns_kset;
 734         init_completion(&ns->ns_kobj_unregister);
 735         err = kobject_init_and_add(&ns->ns_kobj, &ldlm_ns_ktype, NULL,
 736                                    "%s", ldlm_ns_name(ns));
 737
 738         ns->ns_stats = lprocfs_alloc_stats(LDLM_NSS_LAST, 0);
 739         if (!ns->ns_stats) {
 740                 kobject_put(&ns->ns_kobj);
 741                 return -ENOMEM;
 742         }
 743
 744         lprocfs_counter_init(ns->ns_stats, LDLM_NSS_LOCKS,
 745                              LPROCFS_CNTR_AVGMINMAX, "locks", "locks");
 746
 747         return err;
 748 }
 749
 750 static int ldlm_namespace_debugfs_register(struct ldlm_namespace *ns)
 751 {
 752         struct dentry *ns_entry;
 753
 754         if (!IS_ERR_OR_NULL(ns->ns_debugfs_entry)) {
 755                 ns_entry = ns->ns_debugfs_entry;
 756         } else {
 757                 ns_entry = debugfs_create_dir(ldlm_ns_name(ns),
 758                                               ldlm_ns_debugfs_dir);
 759                 if (!ns_entry)
 760                         return -ENOMEM;
 761                 ns->ns_debugfs_entry = ns_entry;
 762         }
 763
 764         return 0;
 765 }
 766 #undef MAX_STRING_SIZE
 767
 768 static unsigned ldlm_res_hop_hash(struct cfs_hash *hs,
 769                                   const void *key, unsigned int mask)
 770 {
 771         const struct ldlm_res_id *id = key;
 772         unsigned int val = 0;
 773         unsigned int i;
 774
 775         for (i = 0; i < RES_NAME_SIZE; i++)
 776                 val += id->name[i];
 777         return val & mask;
 778 }
 779
 780 static unsigned int ldlm_res_hop_fid_hash(const struct ldlm_res_id *id, unsigned int bits)
 781 {
 782         struct lu_fid       fid;
 783         __u32               hash;
 784         __u32               val;
 785
 786         fid.f_seq = id->name[LUSTRE_RES_ID_SEQ_OFF];
 787         fid.f_oid = (__u32)id->name[LUSTRE_RES_ID_VER_OID_OFF];
 788         fid.f_ver = (__u32)(id->name[LUSTRE_RES_ID_VER_OID_OFF] >> 32);
 789
 790         hash = fid_flatten32(&fid);
 791         hash += (hash >> 4) + (hash << 12); /* mixing oid and seq */
 792         if (id->name[LUSTRE_RES_ID_HSH_OFF] != 0) {
 793                 val = id->name[LUSTRE_RES_ID_HSH_OFF];
 794         } else {
 795                 val = fid_oid(&fid);
 796         }
 797         hash += (val >> 5) + (val << 11);
 798         return cfs_hash_32(hash, bits);
 799 }
 800
 801 static void *ldlm_res_hop_key(struct hlist_node *hnode)
 802 {
 803         struct ldlm_resource   *res;
 804
 805         res = hlist_entry(hnode, struct ldlm_resource, lr_hash);
 806         return &res->lr_name;
 807 }
 808
 809 static int ldlm_res_hop_keycmp(const void *key, struct hlist_node *hnode)
 810 {
 811         struct ldlm_resource   *res;
 812
 813         res = hlist_entry(hnode, struct ldlm_resource, lr_hash);
 814         return ldlm_res_eq((const struct ldlm_res_id *)key,
 815                            (const struct ldlm_res_id *)&res->lr_name);
 816 }
 817
 818 static void *ldlm_res_hop_object(struct hlist_node *hnode)
 819 {
 820         return hlist_entry(hnode, struct ldlm_resource, lr_hash);
 821 }
 822
 823 static void
 824 ldlm_res_hop_get_locked(struct cfs_hash *hs, struct hlist_node *hnode)
 825 {
 826         struct ldlm_resource *res;
 827
 828         res = hlist_entry(hnode, struct ldlm_resource, lr_hash);
 829         ldlm_resource_getref(res);
 830 }
 831
 832 static void ldlm_res_hop_put(struct cfs_hash *hs, struct hlist_node *hnode)
 833 {
 834         struct ldlm_resource *res;
 835
 836         res = hlist_entry(hnode, struct ldlm_resource, lr_hash);
 837         ldlm_resource_putref(res);
 838 }
 839
 840 static struct cfs_hash_ops ldlm_ns_hash_ops = {
 841         .hs_hash        = ldlm_res_hop_hash,
 842         .hs_key         = ldlm_res_hop_key,
 843         .hs_keycmp      = ldlm_res_hop_keycmp,
 844         .hs_keycpy      = NULL,
 845         .hs_object      = ldlm_res_hop_object,
 846         .hs_get         = ldlm_res_hop_get_locked,
 847         .hs_put         = ldlm_res_hop_put
 848 };
 849
 850 static struct {
 851         /** hash bucket bits */
 852         unsigned                nsd_bkt_bits;
 853         /** hash bits */
 854         unsigned                nsd_all_bits;
 855 } ldlm_ns_hash_defs[] = {
 856         [LDLM_NS_TYPE_MDC] = {
 857                 .nsd_bkt_bits   = 11,
 858                 .nsd_all_bits   = 16,
 859         },
 860         [LDLM_NS_TYPE_MDT] = {
 861                 .nsd_bkt_bits   = 14,
 862                 .nsd_all_bits   = 21,
 863         },
 864         [LDLM_NS_TYPE_OSC] = {
 865                 .nsd_bkt_bits   = 8,
 866                 .nsd_all_bits   = 12,
 867         },
 868         [LDLM_NS_TYPE_OST] = {
 869                 .nsd_bkt_bits   = 11,
 870                 .nsd_all_bits   = 17,
 871         },
 872         [LDLM_NS_TYPE_MGC] = {
 873                 .nsd_bkt_bits   = 3,
 874                 .nsd_all_bits   = 4,
 875         },
 876         [LDLM_NS_TYPE_MGT] = {
 877                 .nsd_bkt_bits   = 3,
 878                 .nsd_all_bits   = 4,
 879         },
 880 };
 881
 882 /**
 883  * Create and initialize new empty namespace.
 884  */
 885 struct ldlm_namespace *ldlm_namespace_new(struct obd_device *obd, char *name,
 886                                           enum ldlm_side client,
 887                                           enum ldlm_appetite apt,
 888                                           enum ldlm_ns_type ns_type)
 889 {
 890         struct ldlm_namespace *ns = NULL;
 891         int idx;
 892         int rc;
 893
 894         ENTRY;
 895         LASSERT(obd != NULL);
 896
 897         rc = ldlm_get_ref();
 898         if (rc) {
 899                 CERROR("%s: ldlm_get_ref failed: rc = %d\n", name, rc);
 900                 RETURN(ERR_PTR(rc));
 901         }
 902
 903         if (ns_type >= ARRAY_SIZE(ldlm_ns_hash_defs) ||
 904             ldlm_ns_hash_defs[ns_type].nsd_bkt_bits == 0) {
 905                 rc = -EINVAL;
 906                 CERROR("%s: unknown namespace type %d: rc = %d\n",
 907                        name, ns_type, rc);
 908                 GOTO(out_ref, rc);
 909         }
 910
 911         OBD_ALLOC_PTR(ns);
 912         if (!ns)
 913                 GOTO(out_ref, rc = -ENOMEM);
 914
 915         ns->ns_rs_hash = cfs_hash_create(name,
 916                                          ldlm_ns_hash_defs[ns_type].nsd_all_bits,
 917                                          ldlm_ns_hash_defs[ns_type].nsd_all_bits,
 918                                          ldlm_ns_hash_defs[ns_type].nsd_bkt_bits,
 919                                          0,
 920                                          CFS_HASH_MIN_THETA,
 921                                          CFS_HASH_MAX_THETA,
 922                                          &ldlm_ns_hash_ops,
 923                                          CFS_HASH_DEPTH |
 924                                          CFS_HASH_BIGNAME |
 925                                          CFS_HASH_SPIN_BKTLOCK |
 926                                          CFS_HASH_NO_ITEMREF);
 927         if (!ns->ns_rs_hash)
 928                 GOTO(out_ns, rc = -ENOMEM);
 929
 930         ns->ns_bucket_bits = ldlm_ns_hash_defs[ns_type].nsd_all_bits -
 931                              ldlm_ns_hash_defs[ns_type].nsd_bkt_bits;
 932
 933         OBD_ALLOC_PTR_ARRAY_LARGE(ns->ns_rs_buckets, 1 << ns->ns_bucket_bits);
 934         if (!ns->ns_rs_buckets)
 935                 GOTO(out_hash, rc = -ENOMEM);
 936
 937         for (idx = 0; idx < (1 << ns->ns_bucket_bits); idx++) {
 938                 struct ldlm_ns_bucket *nsb = &ns->ns_rs_buckets[idx];
 939
 940                 at_init(&nsb->nsb_at_estimate, ldlm_enqueue_min, 0);
 941                 nsb->nsb_namespace = ns;
 942                 nsb->nsb_reclaim_start = 0;
 943                 atomic_set(&nsb->nsb_count, 0);
 944         }
 945
 946         ns->ns_obd = obd;
 947         ns->ns_appetite = apt;
 948         ns->ns_client = client;
 949         ns->ns_name = kstrdup(name, GFP_KERNEL);
 950         if (!ns->ns_name)
 951                 GOTO(out_hash, rc = -ENOMEM);
 952
 953         INIT_LIST_HEAD(&ns->ns_list_chain);
 954         INIT_LIST_HEAD(&ns->ns_unused_list);
 955         spin_lock_init(&ns->ns_lock);
 956         atomic_set(&ns->ns_bref, 0);
 957         init_waitqueue_head(&ns->ns_waitq);
 958
 959         ns->ns_max_nolock_size    = NS_DEFAULT_MAX_NOLOCK_BYTES;
 960         ns->ns_contention_time    = NS_DEFAULT_CONTENTION_SECONDS;
 961         ns->ns_contended_locks    = NS_DEFAULT_CONTENDED_LOCKS;
 962
 963         ns->ns_max_parallel_ast   = LDLM_DEFAULT_PARALLEL_AST_LIMIT;
 964         ns->ns_nr_unused          = 0;
 965         ns->ns_max_unused         = LDLM_DEFAULT_LRU_SIZE;
 966         ns->ns_cancel_batch       = LDLM_DEFAULT_LRU_SHRINK_BATCH;
 967         ns->ns_recalc_pct         = LDLM_DEFAULT_SLV_RECALC_PCT;
 968         ns->ns_max_age            = ktime_set(LDLM_DEFAULT_MAX_ALIVE, 0);
 969         ns->ns_ctime_age_limit    = LDLM_CTIME_AGE_LIMIT;
 970         ns->ns_dirty_age_limit    = ktime_set(LDLM_DIRTY_AGE_LIMIT, 0);
 971         ns->ns_timeouts           = 0;
 972         ns->ns_orig_connect_flags = 0;
 973         ns->ns_connect_flags      = 0;
 974         ns->ns_stopping           = 0;
 975         ns->ns_reclaim_start      = 0;
 976         ns->ns_last_pos           = &ns->ns_unused_list;
 977         ns->ns_flags              = 0;
 978
 979         rc = ldlm_namespace_sysfs_register(ns);
 980         if (rc) {
 981                 CERROR("%s: cannot initialize ns sysfs: rc = %d\n", name, rc);
 982                 GOTO(out_hash, rc);
 983         }
 984
 985         rc = ldlm_namespace_debugfs_register(ns);
 986         if (rc) {
 987                 CERROR("%s: cannot initialize ns proc: rc = %d\n", name, rc);
 988                 GOTO(out_sysfs, rc);
 989         }
 990
 991         idx = ldlm_namespace_nr_read(client);
 992         rc = ldlm_pool_init(&ns->ns_pool, ns, idx, client);
 993         if (rc) {
 994                 CERROR("%s: cannot initialize lock pool, rc = %d\n", name, rc);
 995                 GOTO(out_proc, rc);
 996         }
 997
 998         ldlm_namespace_register(ns, client);
 999         RETURN(ns);
1000 out_proc:
1001         ldlm_namespace_debugfs_unregister(ns);
1002 out_sysfs:
1003         ldlm_namespace_sysfs_unregister(ns);
1004         ldlm_namespace_cleanup(ns, 0);
1005 out_hash:
1006         OBD_FREE_PTR_ARRAY_LARGE(ns->ns_rs_buckets, 1 << ns->ns_bucket_bits);
1007         kfree(ns->ns_name);
1008         cfs_hash_putref(ns->ns_rs_hash);
1009 out_ns:
1010         OBD_FREE_PTR(ns);
1011 out_ref:
1012         ldlm_put_ref();
1013         RETURN(ERR_PTR(rc));
1014 }
1015 EXPORT_SYMBOL(ldlm_namespace_new);
1016
1017 /**
1018  * Cancel and destroy all locks on a resource.
1019  *
1020  * If flags contains FL_LOCAL_ONLY, don't try to tell the server, just
1021  * clean up.  This is currently only used for recovery, and we make
1022  * certain assumptions as a result--notably, that we shouldn't cancel
1023  * locks with refs.
1024  */
1025 static void cleanup_resource(struct ldlm_resource *res, struct list_head *q,
1026                              __u64 flags)
1027 {
1028         struct list_head *tmp;
1029         int rc = 0, client = ns_is_client(ldlm_res_to_ns(res));
1030         bool local_only = !!(flags & LDLM_FL_LOCAL_ONLY);
1031
1032         do {
1033                 struct ldlm_lock *lock = NULL;
1034
1035                 /* First, we look for non-cleaned-yet lock
1036                  * all cleaned locks are marked by CLEANED flag. */
1037                 lock_res(res);
1038                 list_for_each(tmp, q) {
1039                         lock = list_entry(tmp, struct ldlm_lock,
1040                                           l_res_link);
1041                         if (ldlm_is_cleaned(lock)) {
1042                                 lock = NULL;
1043                                 continue;
1044                         }
1045                         LDLM_LOCK_GET(lock);
1046                         ldlm_set_cleaned(lock);
1047                         break;
1048                 }
1049
1050                 if (lock == NULL) {
1051                         unlock_res(res);
1052                         break;
1053                 }
1054
1055                 /* Set CBPENDING so nothing in the cancellation path
1056                  * can match this lock. */
1057                 ldlm_set_cbpending(lock);
1058                 ldlm_set_failed(lock);
1059                 lock->l_flags |= flags;
1060
1061                 /* ... without sending a CANCEL message for local_only. */
1062                 if (local_only)
1063                         ldlm_set_local_only(lock);
1064
1065                 if (local_only && (lock->l_readers || lock->l_writers)) {
1066                         /*
1067                          * This is a little bit gross, but much better than the
1068                          * alternative: pretend that we got a blocking AST from
1069                          * the server, so that when the lock is decref'd, it
1070                          * will go away ...
1071                          */
1072                         unlock_res(res);
1073                         LDLM_DEBUG(lock, "setting FL_LOCAL_ONLY");
1074                         if (lock->l_flags & LDLM_FL_FAIL_LOC)
1075                                 schedule_timeout_uninterruptible(
1076                                         cfs_time_seconds(4));
1077
1078                         if (lock->l_completion_ast)
1079                                 lock->l_completion_ast(lock,
1080                                                        LDLM_FL_FAILED, NULL);
1081                         LDLM_LOCK_RELEASE(lock);
1082                         continue;
1083                 }
1084
1085                 if (client) {
1086                         struct lustre_handle lockh;
1087
1088                         unlock_res(res);
1089                         ldlm_lock2handle(lock, &lockh);
1090                         rc = ldlm_cli_cancel(&lockh, LCF_LOCAL);
1091                         if (rc)
1092                                 CERROR("ldlm_cli_cancel: %d\n", rc);
1093                 } else {
1094                         unlock_res(res);
1095                         LDLM_DEBUG(lock,
1096                                    "Freeing a lock still held by a client node");
1097                         ldlm_lock_cancel(lock);
1098                 }
1099                 LDLM_LOCK_RELEASE(lock);
1100         } while (1);
1101 }
1102
1103 static int ldlm_resource_clean(struct cfs_hash *hs, struct cfs_hash_bd *bd,
1104                                struct hlist_node *hnode, void *arg)
1105 {
1106         struct ldlm_resource *res = cfs_hash_object(hs, hnode);
1107         __u64 flags = *(__u64 *)arg;
1108
1109         cleanup_resource(res, &res->lr_granted, flags);
1110         cleanup_resource(res, &res->lr_waiting, flags);
1111
1112         return 0;
1113 }
1114
1115 static int ldlm_resource_complain(struct cfs_hash *hs, struct cfs_hash_bd *bd,
1116                                   struct hlist_node *hnode, void *arg)
1117 {
1118         struct ldlm_resource  *res = cfs_hash_object(hs, hnode);
1119
1120         lock_res(res);
1121         CERROR("%s: namespace resource "DLDLMRES" (%p) refcount nonzero "
1122                "(%d) after lock cleanup; forcing cleanup.\n",
1123                ldlm_ns_name(ldlm_res_to_ns(res)), PLDLMRES(res), res,
1124                atomic_read(&res->lr_refcount) - 1);
1125
1126         /* Use D_NETERROR since it is in the default mask */
1127         ldlm_resource_dump(D_NETERROR, res);
1128         unlock_res(res);
1129         return 0;
1130 }
1131
1132 /**
1133  * Cancel and destroy all locks in the namespace.
1134  *
1135  * Typically used during evictions when server notified client that it was
1136  * evicted and all of its state needs to be destroyed.
1137  * Also used during shutdown.
1138  */
1139 int ldlm_namespace_cleanup(struct ldlm_namespace *ns, __u64 flags)
1140 {
1141         if (ns == NULL) {
1142                 CDEBUG(D_INFO, "NULL ns, skipping cleanup\n");
1143                 return ELDLM_OK;
1144         }
1145
1146         cfs_hash_for_each_nolock(ns->ns_rs_hash, ldlm_resource_clean,
1147                                  &flags, 0);
1148         cfs_hash_for_each_nolock(ns->ns_rs_hash, ldlm_resource_complain,
1149                                  NULL, 0);
1150         return ELDLM_OK;
1151 }
1152 EXPORT_SYMBOL(ldlm_namespace_cleanup);
1153
1154 /**
1155  * Attempts to free namespace.
1156  *
1157  * Only used when namespace goes away, like during an unmount.
1158  */
1159 static int __ldlm_namespace_free(struct ldlm_namespace *ns, int force)
1160 {
1161         ENTRY;
1162
1163         /* At shutdown time, don't call the cancellation callback */
1164         ldlm_namespace_cleanup(ns, force ? LDLM_FL_LOCAL_ONLY : 0);
1165
1166         if (atomic_read(&ns->ns_bref) > 0) {
1167                 int rc;
1168                 CDEBUG(D_DLMTRACE,
1169                        "dlm namespace %s free waiting on refcount %d\n",
1170                        ldlm_ns_name(ns), atomic_read(&ns->ns_bref));
1171 force_wait:
1172                 if (force)
1173                         rc = wait_event_idle_timeout(
1174                                 ns->ns_waitq,
1175                                 atomic_read(&ns->ns_bref) == 0,
1176                                 cfs_time_seconds(1) / 4);
1177                 else
1178                         rc = l_wait_event_abortable(
1179                                 ns->ns_waitq, atomic_read(&ns->ns_bref) == 0);
1180
1181                 /* Forced cleanups should be able to reclaim all references,
1182                  * so it's safe to wait forever... we can't leak locks... */
1183                 if (force && rc == 0) {
1184                         rc = -ETIMEDOUT;
1185                         LCONSOLE_ERROR("Forced cleanup waiting for %s "
1186                                        "namespace with %d resources in use, "
1187                                        "(rc=%d)\n", ldlm_ns_name(ns),
1188                                        atomic_read(&ns->ns_bref), rc);
1189                         GOTO(force_wait, rc);
1190                 }
1191
1192                 if (atomic_read(&ns->ns_bref)) {
1193                         LCONSOLE_ERROR("Cleanup waiting for %s namespace "
1194                                        "with %d resources in use, (rc=%d)\n",
1195                                        ldlm_ns_name(ns),
1196                                        atomic_read(&ns->ns_bref), rc);
1197                         RETURN(ELDLM_NAMESPACE_EXISTS);
1198                 }
1199                 CDEBUG(D_DLMTRACE, "dlm namespace %s free done waiting\n",
1200                        ldlm_ns_name(ns));
1201         }
1202
1203         RETURN(ELDLM_OK);
1204 }
1205
1206 /**
1207  * Performs various cleanups for passed \a ns to make it drop refc and be
1208  * ready for freeing. Waits for refc == 0.
1209  *
1210  * The following is done:
1211  * (0) Unregister \a ns from its list to make inaccessible for potential
1212  * users like pools thread and others;
1213  * (1) Clear all locks in \a ns.
1214  */
1215 void ldlm_namespace_free_prior(struct ldlm_namespace *ns,
1216                                struct obd_import *imp,
1217                                int force)
1218 {
1219         int rc;
1220
1221         ENTRY;
1222         if (!ns) {
1223                 EXIT;
1224                 return;
1225         }
1226
1227         spin_lock(&ns->ns_lock);
1228         ns->ns_stopping = 1;
1229         spin_unlock(&ns->ns_lock);
1230
1231         /*
1232          * Can fail with -EINTR when force == 0 in which case try harder.
1233          */
1234         rc = __ldlm_namespace_free(ns, force);
1235         if (rc != ELDLM_OK) {
1236                 if (imp) {
1237                         ptlrpc_disconnect_import(imp, 0);
1238                         ptlrpc_invalidate_import(imp);
1239                 }
1240
1241                 /*
1242                  * With all requests dropped and the import inactive
1243                  * we are gaurenteed all reference will be dropped.
1244                  */
1245                 rc = __ldlm_namespace_free(ns, 1);
1246                 LASSERT(rc == 0);
1247         }
1248         EXIT;
1249 }
1250 EXPORT_SYMBOL(ldlm_namespace_free_prior);
1251
1252 /**
1253  * Performs freeing memory structures related to \a ns. This is only done
1254  * when ldlm_namespce_free_prior() successfully removed all resources
1255  * referencing \a ns and its refc == 0.
1256  */
1257 void ldlm_namespace_free_post(struct ldlm_namespace *ns)
1258 {
1259         ENTRY;
1260         if (!ns) {
1261                 EXIT;
1262                 return;
1263         }
1264
1265         /* Make sure that nobody can find this ns in its list. */
1266         ldlm_namespace_unregister(ns, ns->ns_client);
1267         /* Fini pool _before_ parent proc dir is removed. This is important as
1268          * ldlm_pool_fini() removes own proc dir which is child to @dir.
1269          * Removing it after @dir may cause oops. */
1270         ldlm_pool_fini(&ns->ns_pool);
1271
1272         ldlm_namespace_debugfs_unregister(ns);
1273         ldlm_namespace_sysfs_unregister(ns);
1274         cfs_hash_putref(ns->ns_rs_hash);
1275         OBD_FREE_PTR_ARRAY_LARGE(ns->ns_rs_buckets, 1 << ns->ns_bucket_bits);
1276         kfree(ns->ns_name);
1277         /* Namespace \a ns should be not on list at this time, otherwise
1278          * this will cause issues related to using freed \a ns in poold
1279          * thread.
1280          */
1281         LASSERT(list_empty(&ns->ns_list_chain));
1282         OBD_FREE_PTR(ns);
1283         ldlm_put_ref();
1284         EXIT;
1285 }
1286 EXPORT_SYMBOL(ldlm_namespace_free_post);
1287
1288 /**
1289  * Cleanup the resource, and free namespace.
1290  * bug 12864:
1291  * Deadlock issue:
1292  * proc1: destroy import
1293  *        class_disconnect_export(grab cl_sem) ->
1294  *              -> ldlm_namespace_free ->
1295  *              -> lprocfs_remove(grab _lprocfs_lock).
1296  * proc2: read proc info
1297  *        lprocfs_fops_read(grab _lprocfs_lock) ->
1298  *              -> osc_rd_active, etc(grab cl_sem).
1299  *
1300  * So that I have to split the ldlm_namespace_free into two parts - the first
1301  * part ldlm_namespace_free_prior is used to cleanup the resource which is
1302  * being used; the 2nd part ldlm_namespace_free_post is used to unregister the
1303  * lprocfs entries, and then free memory. It will be called w/o cli->cl_sem
1304  * held.
1305  */
1306 void ldlm_namespace_free(struct ldlm_namespace *ns,
1307                          struct obd_import *imp,
1308                          int force)
1309 {
1310         ldlm_namespace_free_prior(ns, imp, force);
1311         ldlm_namespace_free_post(ns);
1312 }
1313 EXPORT_SYMBOL(ldlm_namespace_free);
1314
1315 void ldlm_namespace_get(struct ldlm_namespace *ns)
1316 {
1317         atomic_inc(&ns->ns_bref);
1318 }
1319
1320 /* This is only for callers that care about refcount */
1321 static int ldlm_namespace_get_return(struct ldlm_namespace *ns)
1322 {
1323         return atomic_inc_return(&ns->ns_bref);
1324 }
1325
1326 void ldlm_namespace_put(struct ldlm_namespace *ns)
1327 {
1328         if (atomic_dec_and_lock(&ns->ns_bref, &ns->ns_lock)) {
1329                 wake_up(&ns->ns_waitq);
1330                 spin_unlock(&ns->ns_lock);
1331         }
1332 }
1333
1334 /** Register \a ns in the list of namespaces */
1335 void ldlm_namespace_register(struct ldlm_namespace *ns, enum ldlm_side client)
1336 {
1337         mutex_lock(ldlm_namespace_lock(client));
1338         LASSERT(list_empty(&ns->ns_list_chain));
1339         list_add(&ns->ns_list_chain, ldlm_namespace_inactive_list(client));
1340         ldlm_namespace_nr_inc(client);
1341         mutex_unlock(ldlm_namespace_lock(client));
1342 }
1343
1344 /** Unregister \a ns from the list of namespaces. */
1345 void ldlm_namespace_unregister(struct ldlm_namespace *ns, enum ldlm_side client)
1346 {
1347         mutex_lock(ldlm_namespace_lock(client));
1348         LASSERT(!list_empty(&ns->ns_list_chain));
1349         /* Some asserts and possibly other parts of the code are still
1350          * using list_empty(&ns->ns_list_chain). This is why it is
1351          * important to use list_del_init() here. */
1352         list_del_init(&ns->ns_list_chain);
1353         ldlm_namespace_nr_dec(client);
1354         mutex_unlock(ldlm_namespace_lock(client));
1355 }
1356
1357 /** Should be called with ldlm_namespace_lock(client) taken. */
1358 void ldlm_namespace_move_to_active_locked(struct ldlm_namespace *ns,
1359                                           enum ldlm_side client)
1360 {
1361         LASSERT(!list_empty(&ns->ns_list_chain));
1362         LASSERT(mutex_is_locked(ldlm_namespace_lock(client)));
1363         list_move_tail(&ns->ns_list_chain, ldlm_namespace_list(client));
1364 }
1365
1366 /** Should be called with ldlm_namespace_lock(client) taken. */
1367 void ldlm_namespace_move_to_inactive_locked(struct ldlm_namespace *ns,
1368                                             enum ldlm_side client)
1369 {
1370         LASSERT(!list_empty(&ns->ns_list_chain));
1371         LASSERT(mutex_is_locked(ldlm_namespace_lock(client)));
1372         list_move_tail(&ns->ns_list_chain,
1373                        ldlm_namespace_inactive_list(client));
1374 }
1375
1376 /** Should be called with ldlm_namespace_lock(client) taken. */
1377 struct ldlm_namespace *ldlm_namespace_first_locked(enum ldlm_side client)
1378 {
1379         LASSERT(mutex_is_locked(ldlm_namespace_lock(client)));
1380         LASSERT(!list_empty(ldlm_namespace_list(client)));
1381         return container_of(ldlm_namespace_list(client)->next,
1382                             struct ldlm_namespace, ns_list_chain);
1383 }
1384
1385 static bool ldlm_resource_extent_new(struct ldlm_resource *res)
1386 {
1387         int idx;
1388
1389         OBD_SLAB_ALLOC(res->lr_itree, ldlm_interval_tree_slab,
1390                        sizeof(*res->lr_itree) * LCK_MODE_NUM);
1391         if (res->lr_itree == NULL)
1392                 return false;
1393         /* Initialize interval trees for each lock mode. */
1394         for (idx = 0; idx < LCK_MODE_NUM; idx++) {
1395                 res->lr_itree[idx].lit_size = 0;
1396                 res->lr_itree[idx].lit_mode = BIT(idx);
1397                 res->lr_itree[idx].lit_root = NULL;
1398         }
1399         return true;
1400 }
1401
1402 static bool ldlm_resource_inodebits_new(struct ldlm_resource *res)
1403 {
1404         int i;
1405
1406         OBD_ALLOC_PTR(res->lr_ibits_queues);
1407         if (res->lr_ibits_queues == NULL)
1408                 return false;
1409         for (i = 0; i < MDS_INODELOCK_NUMBITS; i++)
1410                 INIT_LIST_HEAD(&res->lr_ibits_queues->liq_waiting[i]);
1411         return true;
1412 }
1413
1414 /** Create and initialize new resource. */
1415 static struct ldlm_resource *ldlm_resource_new(enum ldlm_type ldlm_type)
1416 {
1417         struct ldlm_resource *res;
1418         bool rc;
1419
1420         OBD_SLAB_ALLOC_PTR_GFP(res, ldlm_resource_slab, GFP_NOFS);
1421         if (res == NULL)
1422                 return NULL;
1423
1424         switch (ldlm_type) {
1425         case LDLM_EXTENT:
1426                 rc = ldlm_resource_extent_new(res);
1427                 break;
1428         case LDLM_IBITS:
1429                 rc = ldlm_resource_inodebits_new(res);
1430                 break;
1431         default:
1432                 rc = true;
1433                 break;
1434         }
1435         if (!rc) {
1436                 OBD_SLAB_FREE_PTR(res, ldlm_resource_slab);
1437                 return NULL;
1438         }
1439
1440         INIT_LIST_HEAD(&res->lr_granted);
1441         INIT_LIST_HEAD(&res->lr_waiting);
1442
1443         atomic_set(&res->lr_refcount, 1);
1444         spin_lock_init(&res->lr_lock);
1445         lu_ref_init(&res->lr_reference);
1446
1447         /* Since LVB init can be delayed now, there is no longer need to
1448          * immediatelly acquire mutex here. */
1449         mutex_init(&res->lr_lvb_mutex);
1450         res->lr_lvb_initialized = false;
1451
1452         return res;
1453 }
1454
1455 static void __ldlm_resource_free(struct rcu_head *head)
1456 {
1457         struct ldlm_resource *res = container_of(head, struct ldlm_resource,
1458                                                  lr_rcu);
1459
1460         OBD_SLAB_FREE_PTR(res, ldlm_resource_slab);
1461 }
1462
1463 static void ldlm_resource_free(struct ldlm_resource *res)
1464 {
1465         if (res->lr_type == LDLM_EXTENT) {
1466                 if (res->lr_itree != NULL)
1467                         OBD_SLAB_FREE(res->lr_itree, ldlm_interval_tree_slab,
1468                                       sizeof(*res->lr_itree) * LCK_MODE_NUM);
1469         } else if (res->lr_type == LDLM_IBITS) {
1470                 if (res->lr_ibits_queues != NULL)
1471                         OBD_FREE_PTR(res->lr_ibits_queues);
1472         }
1473
1474         call_rcu(&res->lr_rcu, __ldlm_resource_free);
1475 }
1476
1477 /**
1478  * Return a reference to resource with given name, creating it if necessary.
1479  * Args: namespace with ns_lock unlocked
1480  * Locks: takes and releases NS hash-lock and res->lr_lock
1481  * Returns: referenced, unlocked ldlm_resource or ERR_PTR
1482  */
1483 struct ldlm_resource *
1484 ldlm_resource_get(struct ldlm_namespace *ns, const struct ldlm_res_id *name,
1485                   enum ldlm_type type, int create)
1486 {
1487         struct hlist_node       *hnode;
1488         struct ldlm_resource    *res = NULL;
1489         struct cfs_hash_bd              bd;
1490         __u64                   version;
1491         int                     ns_refcount = 0;
1492         int hash;
1493
1494         LASSERT(ns != NULL);
1495         LASSERT(ns->ns_rs_hash != NULL);
1496         LASSERT(name->name[0] != 0);
1497
1498         cfs_hash_bd_get_and_lock(ns->ns_rs_hash, (void *)name, &bd, 0);
1499         hnode = cfs_hash_bd_lookup_locked(ns->ns_rs_hash, &bd, (void *)name);
1500         if (hnode != NULL) {
1501                 cfs_hash_bd_unlock(ns->ns_rs_hash, &bd, 0);
1502                 GOTO(found, res);
1503         }
1504
1505         version = cfs_hash_bd_version_get(&bd);
1506         cfs_hash_bd_unlock(ns->ns_rs_hash, &bd, 0);
1507
1508         if (create == 0)
1509                 return ERR_PTR(-ENOENT);
1510
1511         LASSERTF(type >= LDLM_MIN_TYPE && type < LDLM_MAX_TYPE,
1512                  "type: %d\n", type);
1513         res = ldlm_resource_new(type);
1514         if (res == NULL)
1515                 return ERR_PTR(-ENOMEM);
1516
1517         hash = ldlm_res_hop_fid_hash(name, ns->ns_bucket_bits);
1518         res->lr_ns_bucket = &ns->ns_rs_buckets[hash];
1519         res->lr_name = *name;
1520         res->lr_type = type;
1521
1522         cfs_hash_bd_lock(ns->ns_rs_hash, &bd, 1);
1523         hnode = (version == cfs_hash_bd_version_get(&bd)) ? NULL :
1524                 cfs_hash_bd_lookup_locked(ns->ns_rs_hash, &bd, (void *)name);
1525
1526         if (hnode != NULL) {
1527                 /* Someone won the race and already added the resource. */
1528                 cfs_hash_bd_unlock(ns->ns_rs_hash, &bd, 1);
1529                 /* Clean lu_ref for failed resource. */
1530                 lu_ref_fini(&res->lr_reference);
1531                 ldlm_resource_free(res);
1532 found:
1533                 res = hlist_entry(hnode, struct ldlm_resource, lr_hash);
1534                 return res;
1535         }
1536         /* We won! Let's add the resource. */
1537         cfs_hash_bd_add_locked(ns->ns_rs_hash, &bd, &res->lr_hash);
1538         if (atomic_inc_return(&res->lr_ns_bucket->nsb_count) == 1)
1539                 ns_refcount = ldlm_namespace_get_return(ns);
1540
1541         cfs_hash_bd_unlock(ns->ns_rs_hash, &bd, 1);
1542
1543         OBD_FAIL_TIMEOUT(OBD_FAIL_LDLM_CREATE_RESOURCE, 2);
1544
1545         /* Let's see if we happened to be the very first resource in this
1546          * namespace. If so, and this is a client namespace, we need to move
1547          * the namespace into the active namespaces list to be patrolled by
1548          * the ldlm_poold. */
1549         if (ns_is_client(ns) && ns_refcount == 1) {
1550                 mutex_lock(ldlm_namespace_lock(LDLM_NAMESPACE_CLIENT));
1551                 ldlm_namespace_move_to_active_locked(ns, LDLM_NAMESPACE_CLIENT);
1552                 mutex_unlock(ldlm_namespace_lock(LDLM_NAMESPACE_CLIENT));
1553         }
1554
1555         return res;
1556 }
1557 EXPORT_SYMBOL(ldlm_resource_get);
1558
1559 struct ldlm_resource *ldlm_resource_getref(struct ldlm_resource *res)
1560 {
1561         LASSERT(res != NULL);
1562         LASSERT(res != LP_POISON);
1563         atomic_inc(&res->lr_refcount);
1564         CDEBUG(D_INFO, "getref res: %p count: %d\n", res,
1565                atomic_read(&res->lr_refcount));
1566         return res;
1567 }
1568
1569 static void __ldlm_resource_putref_final(struct cfs_hash_bd *bd,
1570                                          struct ldlm_resource *res)
1571 {
1572         struct ldlm_ns_bucket *nsb = res->lr_ns_bucket;
1573
1574         if (!list_empty(&res->lr_granted)) {
1575                 ldlm_resource_dump(D_ERROR, res);
1576                 LBUG();
1577         }
1578
1579         if (!list_empty(&res->lr_waiting)) {
1580                 ldlm_resource_dump(D_ERROR, res);
1581                 LBUG();
1582         }
1583
1584         cfs_hash_bd_del_locked(nsb->nsb_namespace->ns_rs_hash,
1585                                bd, &res->lr_hash);
1586         lu_ref_fini(&res->lr_reference);
1587         if (atomic_dec_and_test(&nsb->nsb_count))
1588                 ldlm_namespace_put(nsb->nsb_namespace);
1589 }
1590
1591 /* Returns 1 if the resource was freed, 0 if it remains. */
1592 int ldlm_resource_putref(struct ldlm_resource *res)
1593 {
1594         struct ldlm_namespace *ns = ldlm_res_to_ns(res);
1595         struct cfs_hash_bd   bd;
1596
1597         LASSERT_ATOMIC_GT_LT(&res->lr_refcount, 0, LI_POISON);
1598         CDEBUG(D_INFO, "putref res: %p count: %d\n",
1599                res, atomic_read(&res->lr_refcount) - 1);
1600
1601         cfs_hash_bd_get(ns->ns_rs_hash, &res->lr_name, &bd);
1602         if (cfs_hash_bd_dec_and_lock(ns->ns_rs_hash, &bd, &res->lr_refcount)) {
1603                 __ldlm_resource_putref_final(&bd, res);
1604                 cfs_hash_bd_unlock(ns->ns_rs_hash, &bd, 1);
1605                 if (ns->ns_lvbo && ns->ns_lvbo->lvbo_free)
1606                         ns->ns_lvbo->lvbo_free(res);
1607                 ldlm_resource_free(res);
1608                 return 1;
1609         }
1610         return 0;
1611 }
1612 EXPORT_SYMBOL(ldlm_resource_putref);
1613
1614 static void __ldlm_resource_add_lock(struct ldlm_resource *res,
1615                                      struct list_head *head,
1616                                      struct ldlm_lock *lock,
1617                                      bool tail)
1618 {
1619         check_res_locked(res);
1620
1621         if (ldlm_is_destroyed(lock)) {
1622                 CDEBUG(D_OTHER, "Lock destroyed, not adding to resource\n");
1623                 return;
1624         }
1625
1626         LASSERT(list_empty(&lock->l_res_link));
1627
1628         if (tail)
1629                 list_add_tail(&lock->l_res_link, head);
1630         else
1631                 list_add(&lock->l_res_link, head);
1632
1633         if (res->lr_type == LDLM_IBITS)
1634                 ldlm_inodebits_add_lock(res, head, lock, tail);
1635
1636         ldlm_resource_dump(D_INFO, res);
1637 }
1638
1639 /**
1640  * Add a lock into a given resource into specified lock list.
1641  */
1642 void ldlm_resource_add_lock(struct ldlm_resource *res, struct list_head *head,
1643                             struct ldlm_lock *lock)
1644 {
1645         LDLM_DEBUG(lock, "About to add this lock");
1646
1647         __ldlm_resource_add_lock(res, head, lock, true);
1648 }
1649
1650 /**
1651  * Insert a lock into resource after specified lock.
1652  */
1653 void ldlm_resource_insert_lock_after(struct ldlm_lock *original,
1654                                      struct ldlm_lock *new)
1655 {
1656         LASSERT(!list_empty(&original->l_res_link));
1657
1658         LDLM_DEBUG(new, "About to insert this lock after %p: ", original);
1659         __ldlm_resource_add_lock(original->l_resource,
1660                                  &original->l_res_link,
1661                                  new, false);
1662 }
1663
1664 /**
1665  * Insert a lock into resource before the specified lock.
1666  *
1667  * IBITS waiting locks are to be inserted to the ibit lists as well, and only
1668  * the insert-after operation is supported for them, because the set of bits
1669  * of the previous and the new locks must match. Therefore, get the previous
1670  * lock and insert after.
1671  */
1672 void ldlm_resource_insert_lock_before(struct ldlm_lock *original,
1673                                       struct ldlm_lock *new)
1674 {
1675         LASSERT(!list_empty(&original->l_res_link));
1676
1677         LDLM_DEBUG(new, "About to insert this lock before %p: ", original);
1678         __ldlm_resource_add_lock(original->l_resource,
1679                                  original->l_res_link.prev, new, false);
1680 }
1681
1682 void ldlm_resource_unlink_lock(struct ldlm_lock *lock)
1683 {
1684         int type = lock->l_resource->lr_type;
1685
1686         check_res_locked(lock->l_resource);
1687         switch (type) {
1688         case LDLM_PLAIN:
1689                 ldlm_unlink_lock_skiplist(lock);
1690                 break;
1691         case LDLM_EXTENT:
1692                 ldlm_extent_unlink_lock(lock);
1693                 break;
1694         case LDLM_IBITS:
1695                 ldlm_inodebits_unlink_lock(lock);
1696                 break;
1697         }
1698         list_del_init(&lock->l_res_link);
1699 }
1700 EXPORT_SYMBOL(ldlm_resource_unlink_lock);
1701
1702 void ldlm_res2desc(struct ldlm_resource *res, struct ldlm_resource_desc *desc)
1703 {
1704         desc->lr_type = res->lr_type;
1705         desc->lr_name = res->lr_name;
1706 }
1707
1708 /**
1709  * Print information about all locks in all namespaces on this node to debug
1710  * log.
1711  */
1712 void ldlm_dump_all_namespaces(enum ldlm_side client, int level)
1713 {
1714         struct list_head *tmp;
1715
1716         if (!((libcfs_debug | D_ERROR) & level))
1717                 return;
1718
1719         mutex_lock(ldlm_namespace_lock(client));
1720
1721         list_for_each(tmp, ldlm_namespace_list(client)) {
1722                 struct ldlm_namespace *ns;
1723
1724                 ns = list_entry(tmp, struct ldlm_namespace, ns_list_chain);
1725                 ldlm_namespace_dump(level, ns);
1726         }
1727
1728         mutex_unlock(ldlm_namespace_lock(client));
1729 }
1730
1731 static int ldlm_res_hash_dump(struct cfs_hash *hs, struct cfs_hash_bd *bd,
1732                               struct hlist_node *hnode, void *arg)
1733 {
1734         struct ldlm_resource *res = cfs_hash_object(hs, hnode);
1735         int    level = (int)(unsigned long)arg;
1736
1737         lock_res(res);
1738         ldlm_resource_dump(level, res);
1739         unlock_res(res);
1740
1741         return 0;
1742 }
1743
1744 /**
1745  * Print information about all locks in this namespace on this node to debug
1746  * log.
1747  */
1748 void ldlm_namespace_dump(int level, struct ldlm_namespace *ns)
1749 {
1750         if (!((libcfs_debug | D_ERROR) & level))
1751                 return;
1752
1753         CDEBUG(level, "--- Namespace: %s (rc: %d, side: %s)\n",
1754                ldlm_ns_name(ns), atomic_read(&ns->ns_bref),
1755                ns_is_client(ns) ? "client" : "server");
1756
1757         if (ktime_get_seconds() < ns->ns_next_dump)
1758                 return;
1759
1760         cfs_hash_for_each_nolock(ns->ns_rs_hash,
1761                                  ldlm_res_hash_dump,
1762                                  (void *)(unsigned long)level, 0);
1763         spin_lock(&ns->ns_lock);
1764         ns->ns_next_dump = ktime_get_seconds() + 10;
1765         spin_unlock(&ns->ns_lock);
1766 }
1767
1768 /**
1769  * Print information about all locks in this resource to debug log.
1770  */
1771 void ldlm_resource_dump(int level, struct ldlm_resource *res)
1772 {
1773         struct ldlm_lock *lock;
1774         unsigned int granted = 0;
1775
1776         BUILD_BUG_ON(RES_NAME_SIZE != 4);
1777
1778         if (!((libcfs_debug | D_ERROR) & level))
1779                 return;
1780
1781         CDEBUG(level, "--- Resource: "DLDLMRES" (%p) refcount = %d\n",
1782                PLDLMRES(res), res, atomic_read(&res->lr_refcount));
1783
1784         if (!list_empty(&res->lr_granted)) {
1785                 CDEBUG(level, "Granted locks (in reverse order):\n");
1786                 list_for_each_entry_reverse(lock, &res->lr_granted,
1787                                                 l_res_link) {
1788                         LDLM_DEBUG_LIMIT(level, lock, "###");
1789                         if (!(level & D_CANTMASK) &&
1790                             ++granted > ldlm_dump_granted_max) {
1791                                 CDEBUG(level,
1792                                        "only dump %d granted locks to avoid DDOS.\n",
1793                                        granted);
1794                                 break;
1795                         }
1796                 }
1797         }
1798
1799         if (!list_empty(&res->lr_waiting)) {
1800                 CDEBUG(level, "Waiting locks:\n");
1801                 list_for_each_entry(lock, &res->lr_waiting, l_res_link)
1802                         LDLM_DEBUG_LIMIT(level, lock, "###");
1803         }
1804 }
1805 EXPORT_SYMBOL(ldlm_resource_dump);