4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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.
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).
16 * You should have received a copy of the GNU General Public License
17 * version 2 along with this program; If not, see
18 * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
20 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
21 * CA 95054 USA or visit www.sun.com if you need additional information or
27 * Copyright (c) 2002, 2010, Oracle and/or its affiliates. All rights reserved.
28 * Use is subject to license terms.
30 * Copyright (c) 2010, 2012, Intel Corporation.
33 * This file is part of Lustre, http://www.lustre.org/
34 * Lustre is a trademark of Sun Microsystems, Inc.
36 * lustre/ldlm/ldlm_resource.c
38 * Author: Phil Schwan <phil@clusterfs.com>
39 * Author: Peter Braam <braam@clusterfs.com>
42 #define DEBUG_SUBSYSTEM S_LDLM
44 # include <lustre_dlm.h>
46 # include <liblustre.h>
49 #include <lustre_fid.h>
50 #include <obd_class.h>
51 #include "ldlm_internal.h"
53 cfs_mem_cache_t *ldlm_resource_slab, *ldlm_lock_slab;
55 cfs_atomic_t ldlm_srv_namespace_nr = CFS_ATOMIC_INIT(0);
56 cfs_atomic_t ldlm_cli_namespace_nr = CFS_ATOMIC_INIT(0);
58 struct mutex ldlm_srv_namespace_lock;
59 CFS_LIST_HEAD(ldlm_srv_namespace_list);
61 struct mutex ldlm_cli_namespace_lock;
62 CFS_LIST_HEAD(ldlm_cli_namespace_list);
64 cfs_proc_dir_entry_t *ldlm_type_proc_dir = NULL;
65 cfs_proc_dir_entry_t *ldlm_ns_proc_dir = NULL;
66 cfs_proc_dir_entry_t *ldlm_svc_proc_dir = NULL;
68 extern unsigned int ldlm_cancel_unused_locks_before_replay;
70 /* during debug dump certain amount of granted locks for one resource to avoid
72 unsigned int ldlm_dump_granted_max = 256;
75 static int ldlm_proc_dump_ns(struct file *file, const char *buffer,
76 unsigned long count, void *data)
78 ldlm_dump_all_namespaces(LDLM_NAMESPACE_SERVER, D_DLMTRACE);
79 ldlm_dump_all_namespaces(LDLM_NAMESPACE_CLIENT, D_DLMTRACE);
83 int ldlm_proc_setup(void)
86 struct lprocfs_vars list[] = {
87 { "dump_namespaces", NULL, ldlm_proc_dump_ns, NULL },
89 lprocfs_rd_uint, lprocfs_wr_uint,
90 &ldlm_dump_granted_max, NULL },
91 { "cancel_unused_locks_before_replay",
92 lprocfs_rd_uint, lprocfs_wr_uint,
93 &ldlm_cancel_unused_locks_before_replay, NULL },
96 LASSERT(ldlm_ns_proc_dir == NULL);
98 ldlm_type_proc_dir = lprocfs_register(OBD_LDLM_DEVICENAME,
101 if (IS_ERR(ldlm_type_proc_dir)) {
102 CERROR("LProcFS failed in ldlm-init\n");
103 rc = PTR_ERR(ldlm_type_proc_dir);
107 ldlm_ns_proc_dir = lprocfs_register("namespaces",
110 if (IS_ERR(ldlm_ns_proc_dir)) {
111 CERROR("LProcFS failed in ldlm-init\n");
112 rc = PTR_ERR(ldlm_ns_proc_dir);
116 ldlm_svc_proc_dir = lprocfs_register("services",
119 if (IS_ERR(ldlm_svc_proc_dir)) {
120 CERROR("LProcFS failed in ldlm-init\n");
121 rc = PTR_ERR(ldlm_svc_proc_dir);
125 rc = lprocfs_add_vars(ldlm_type_proc_dir, list, NULL);
130 lprocfs_remove(&ldlm_ns_proc_dir);
132 lprocfs_remove(&ldlm_type_proc_dir);
134 ldlm_svc_proc_dir = NULL;
138 void ldlm_proc_cleanup(void)
140 if (ldlm_svc_proc_dir)
141 lprocfs_remove(&ldlm_svc_proc_dir);
143 if (ldlm_ns_proc_dir)
144 lprocfs_remove(&ldlm_ns_proc_dir);
146 if (ldlm_type_proc_dir)
147 lprocfs_remove(&ldlm_type_proc_dir);
150 static int lprocfs_rd_ns_resources(char *page, char **start, off_t off,
151 int count, int *eof, void *data)
153 struct ldlm_namespace *ns = data;
158 /* result is not strictly consistant */
159 cfs_hash_for_each_bucket(ns->ns_rs_hash, &bd, i)
160 res += cfs_hash_bd_count_get(&bd);
161 return lprocfs_rd_u64(page, start, off, count, eof, &res);
164 static int lprocfs_rd_ns_locks(char *page, char **start, off_t off,
165 int count, int *eof, void *data)
167 struct ldlm_namespace *ns = data;
170 locks = lprocfs_stats_collector(ns->ns_stats, LDLM_NSS_LOCKS,
171 LPROCFS_FIELDS_FLAGS_SUM);
172 return lprocfs_rd_u64(page, start, off, count, eof, &locks);
175 static int lprocfs_rd_lru_size(char *page, char **start, off_t off,
176 int count, int *eof, void *data)
178 struct ldlm_namespace *ns = data;
179 __u32 *nr = &ns->ns_max_unused;
181 if (ns_connect_lru_resize(ns))
182 nr = &ns->ns_nr_unused;
183 return lprocfs_rd_uint(page, start, off, count, eof, nr);
186 static int lprocfs_wr_lru_size(struct file *file, const char *buffer,
187 unsigned long count, void *data)
189 struct ldlm_namespace *ns = data;
190 char dummy[MAX_STRING_SIZE + 1], *end;
194 dummy[MAX_STRING_SIZE] = '\0';
195 if (cfs_copy_from_user(dummy, buffer, MAX_STRING_SIZE))
198 if (strncmp(dummy, "clear", 5) == 0) {
200 "dropping all unused locks from namespace %s\n",
202 if (ns_connect_lru_resize(ns)) {
203 int canceled, unused = ns->ns_nr_unused;
205 /* Try to cancel all @ns_nr_unused locks. */
206 canceled = ldlm_cancel_lru(ns, unused, LDLM_SYNC,
208 if (canceled < unused) {
210 "not all requested locks are canceled, "
211 "requested: %d, canceled: %d\n", unused,
216 tmp = ns->ns_max_unused;
217 ns->ns_max_unused = 0;
218 ldlm_cancel_lru(ns, 0, LDLM_SYNC, LDLM_CANCEL_PASSED);
219 ns->ns_max_unused = tmp;
224 tmp = simple_strtoul(dummy, &end, 0);
226 CERROR("invalid value written\n");
229 lru_resize = (tmp == 0);
231 if (ns_connect_lru_resize(ns)) {
233 ns->ns_max_unused = (unsigned int)tmp;
235 if (tmp > ns->ns_nr_unused)
236 tmp = ns->ns_nr_unused;
237 tmp = ns->ns_nr_unused - tmp;
240 "changing namespace %s unused locks from %u to %u\n",
241 ldlm_ns_name(ns), ns->ns_nr_unused,
243 ldlm_cancel_lru(ns, tmp, LDLM_ASYNC, LDLM_CANCEL_PASSED);
247 "disable lru_resize for namespace %s\n",
249 ns->ns_connect_flags &= ~OBD_CONNECT_LRU_RESIZE;
253 "changing namespace %s max_unused from %u to %u\n",
254 ldlm_ns_name(ns), ns->ns_max_unused,
256 ns->ns_max_unused = (unsigned int)tmp;
257 ldlm_cancel_lru(ns, 0, LDLM_ASYNC, LDLM_CANCEL_PASSED);
259 /* Make sure that LRU resize was originally supported before
260 * turning it on here. */
262 (ns->ns_orig_connect_flags & OBD_CONNECT_LRU_RESIZE)) {
264 "enable lru_resize for namespace %s\n",
266 ns->ns_connect_flags |= OBD_CONNECT_LRU_RESIZE;
273 static int lprocfs_rd_elc(char *page, char **start, off_t off,
274 int count, int *eof, void *data)
276 struct ldlm_namespace *ns = data;
277 unsigned int supp = ns_connect_cancelset(ns);
279 return lprocfs_rd_uint(page, start, off, count, eof, &supp);
282 static int lprocfs_wr_elc(struct file *file, const char *buffer,
283 unsigned long count, void *data)
285 struct ldlm_namespace *ns = data;
286 unsigned int supp = -1;
289 rc = lprocfs_wr_uint(file, buffer, count, &supp);
294 ns->ns_connect_flags &= ~OBD_CONNECT_CANCELSET;
295 else if (ns->ns_orig_connect_flags & OBD_CONNECT_CANCELSET)
296 ns->ns_connect_flags |= OBD_CONNECT_CANCELSET;
300 void ldlm_namespace_proc_unregister(struct ldlm_namespace *ns)
302 struct proc_dir_entry *dir;
304 dir = lprocfs_srch(ldlm_ns_proc_dir, ldlm_ns_name(ns));
306 CERROR("dlm namespace %s has no procfs dir?\n",
309 lprocfs_remove(&dir);
312 if (ns->ns_stats != NULL)
313 lprocfs_free_stats(&ns->ns_stats);
316 int ldlm_namespace_proc_register(struct ldlm_namespace *ns)
318 struct lprocfs_vars lock_vars[2];
319 char lock_name[MAX_STRING_SIZE + 1];
322 LASSERT(ns->ns_rs_hash != NULL);
324 ns->ns_stats = lprocfs_alloc_stats(LDLM_NSS_LAST, 0);
325 if (ns->ns_stats == NULL)
328 lprocfs_counter_init(ns->ns_stats, LDLM_NSS_LOCKS,
329 LPROCFS_CNTR_AVGMINMAX, "locks", "locks");
331 lock_name[MAX_STRING_SIZE] = '\0';
333 memset(lock_vars, 0, sizeof(lock_vars));
334 lock_vars[0].name = lock_name;
336 snprintf(lock_name, MAX_STRING_SIZE, "%s/resource_count",
338 lock_vars[0].data = ns;
339 lock_vars[0].read_fptr = lprocfs_rd_ns_resources;
340 lprocfs_add_vars(ldlm_ns_proc_dir, lock_vars, 0);
342 snprintf(lock_name, MAX_STRING_SIZE, "%s/lock_count",
344 lock_vars[0].data = ns;
345 lock_vars[0].read_fptr = lprocfs_rd_ns_locks;
346 lprocfs_add_vars(ldlm_ns_proc_dir, lock_vars, 0);
348 if (ns_is_client(ns)) {
349 snprintf(lock_name, MAX_STRING_SIZE, "%s/lock_unused_count",
351 lock_vars[0].data = &ns->ns_nr_unused;
352 lock_vars[0].read_fptr = lprocfs_rd_uint;
353 lprocfs_add_vars(ldlm_ns_proc_dir, lock_vars, 0);
355 snprintf(lock_name, MAX_STRING_SIZE, "%s/lru_size",
357 lock_vars[0].data = ns;
358 lock_vars[0].read_fptr = lprocfs_rd_lru_size;
359 lock_vars[0].write_fptr = lprocfs_wr_lru_size;
360 lprocfs_add_vars(ldlm_ns_proc_dir, lock_vars, 0);
362 snprintf(lock_name, MAX_STRING_SIZE, "%s/lru_max_age",
364 lock_vars[0].data = &ns->ns_max_age;
365 lock_vars[0].read_fptr = lprocfs_rd_uint;
366 lock_vars[0].write_fptr = lprocfs_wr_uint;
367 lprocfs_add_vars(ldlm_ns_proc_dir, lock_vars, 0);
369 snprintf(lock_name, MAX_STRING_SIZE, "%s/early_lock_cancel",
371 lock_vars[0].data = ns;
372 lock_vars[0].read_fptr = lprocfs_rd_elc;
373 lock_vars[0].write_fptr = lprocfs_wr_elc;
374 lprocfs_add_vars(ldlm_ns_proc_dir, lock_vars, 0);
376 snprintf(lock_name, MAX_STRING_SIZE, "%s/ctime_age_limit",
378 lock_vars[0].data = &ns->ns_ctime_age_limit;
379 lock_vars[0].read_fptr = lprocfs_rd_uint;
380 lock_vars[0].write_fptr = lprocfs_wr_uint;
381 lprocfs_add_vars(ldlm_ns_proc_dir, lock_vars, 0);
383 snprintf(lock_name, MAX_STRING_SIZE, "%s/lock_timeouts",
385 lock_vars[0].data = &ns->ns_timeouts;
386 lock_vars[0].read_fptr = lprocfs_rd_uint;
387 lprocfs_add_vars(ldlm_ns_proc_dir, lock_vars, 0);
389 snprintf(lock_name, MAX_STRING_SIZE, "%s/max_nolock_bytes",
391 lock_vars[0].data = &ns->ns_max_nolock_size;
392 lock_vars[0].read_fptr = lprocfs_rd_uint;
393 lock_vars[0].write_fptr = lprocfs_wr_uint;
394 lprocfs_add_vars(ldlm_ns_proc_dir, lock_vars, 0);
396 snprintf(lock_name, MAX_STRING_SIZE, "%s/contention_seconds",
398 lock_vars[0].data = &ns->ns_contention_time;
399 lock_vars[0].read_fptr = lprocfs_rd_uint;
400 lock_vars[0].write_fptr = lprocfs_wr_uint;
401 lprocfs_add_vars(ldlm_ns_proc_dir, lock_vars, 0);
403 snprintf(lock_name, MAX_STRING_SIZE, "%s/contended_locks",
405 lock_vars[0].data = &ns->ns_contended_locks;
406 lock_vars[0].read_fptr = lprocfs_rd_uint;
407 lock_vars[0].write_fptr = lprocfs_wr_uint;
408 lprocfs_add_vars(ldlm_ns_proc_dir, lock_vars, 0);
410 snprintf(lock_name, MAX_STRING_SIZE, "%s/max_parallel_ast",
412 lock_vars[0].data = &ns->ns_max_parallel_ast;
413 lock_vars[0].read_fptr = lprocfs_rd_uint;
414 lock_vars[0].write_fptr = lprocfs_wr_uint;
415 lprocfs_add_vars(ldlm_ns_proc_dir, lock_vars, 0);
419 #undef MAX_STRING_SIZE
422 #define ldlm_namespace_proc_unregister(ns) ({;})
423 #define ldlm_namespace_proc_register(ns) ({0;})
427 static unsigned ldlm_res_hop_hash(cfs_hash_t *hs,
428 const void *key, unsigned mask)
430 const struct ldlm_res_id *id = key;
434 for (i = 0; i < RES_NAME_SIZE; i++)
439 static unsigned ldlm_res_hop_fid_hash(cfs_hash_t *hs,
440 const void *key, unsigned mask)
442 const struct ldlm_res_id *id = key;
447 fid.f_seq = id->name[LUSTRE_RES_ID_SEQ_OFF];
448 fid.f_oid = (__u32)id->name[LUSTRE_RES_ID_VER_OID_OFF];
449 fid.f_ver = (__u32)(id->name[LUSTRE_RES_ID_VER_OID_OFF] >> 32);
451 hash = fid_flatten32(&fid);
452 hash += (hash >> 4) + (hash << 12); /* mixing oid and seq */
453 if (id->name[LUSTRE_RES_ID_HSH_OFF] != 0) {
454 val = id->name[LUSTRE_RES_ID_HSH_OFF];
455 hash += (val >> 5) + (val << 11);
459 hash = cfs_hash_long(hash, hs->hs_bkt_bits);
460 /* give me another random factor */
461 hash -= cfs_hash_long((unsigned long)hs, val % 11 + 3);
463 hash <<= hs->hs_cur_bits - hs->hs_bkt_bits;
464 hash |= ldlm_res_hop_hash(hs, key, CFS_HASH_NBKT(hs) - 1);
469 static void *ldlm_res_hop_key(cfs_hlist_node_t *hnode)
471 struct ldlm_resource *res;
473 res = cfs_hlist_entry(hnode, struct ldlm_resource, lr_hash);
474 return &res->lr_name;
477 static int ldlm_res_hop_keycmp(const void *key, cfs_hlist_node_t *hnode)
479 struct ldlm_resource *res;
481 res = cfs_hlist_entry(hnode, struct ldlm_resource, lr_hash);
482 return ldlm_res_eq((const struct ldlm_res_id *)key,
483 (const struct ldlm_res_id *)&res->lr_name);
486 static void *ldlm_res_hop_object(cfs_hlist_node_t *hnode)
488 return cfs_hlist_entry(hnode, struct ldlm_resource, lr_hash);
491 static void ldlm_res_hop_get_locked(cfs_hash_t *hs, cfs_hlist_node_t *hnode)
493 struct ldlm_resource *res;
495 res = cfs_hlist_entry(hnode, struct ldlm_resource, lr_hash);
496 ldlm_resource_getref(res);
499 static void ldlm_res_hop_put_locked(cfs_hash_t *hs, cfs_hlist_node_t *hnode)
501 struct ldlm_resource *res;
503 res = cfs_hlist_entry(hnode, struct ldlm_resource, lr_hash);
504 /* cfs_hash_for_each_nolock is the only chance we call it */
505 ldlm_resource_putref_locked(res);
508 static void ldlm_res_hop_put(cfs_hash_t *hs, cfs_hlist_node_t *hnode)
510 struct ldlm_resource *res;
512 res = cfs_hlist_entry(hnode, struct ldlm_resource, lr_hash);
513 ldlm_resource_putref(res);
516 cfs_hash_ops_t ldlm_ns_hash_ops = {
517 .hs_hash = ldlm_res_hop_hash,
518 .hs_key = ldlm_res_hop_key,
519 .hs_keycmp = ldlm_res_hop_keycmp,
521 .hs_object = ldlm_res_hop_object,
522 .hs_get = ldlm_res_hop_get_locked,
523 .hs_put_locked = ldlm_res_hop_put_locked,
524 .hs_put = ldlm_res_hop_put
527 cfs_hash_ops_t ldlm_ns_fid_hash_ops = {
528 .hs_hash = ldlm_res_hop_fid_hash,
529 .hs_key = ldlm_res_hop_key,
530 .hs_keycmp = ldlm_res_hop_keycmp,
532 .hs_object = ldlm_res_hop_object,
533 .hs_get = ldlm_res_hop_get_locked,
534 .hs_put_locked = ldlm_res_hop_put_locked,
535 .hs_put = ldlm_res_hop_put
539 ldlm_ns_type_t nsd_type;
540 /** hash bucket bits */
541 unsigned nsd_bkt_bits;
543 unsigned nsd_all_bits;
544 /** hash operations */
545 cfs_hash_ops_t *nsd_hops;
546 } ldlm_ns_hash_def_t;
548 ldlm_ns_hash_def_t ldlm_ns_hash_defs[] =
551 .nsd_type = LDLM_NS_TYPE_MDC,
554 .nsd_hops = &ldlm_ns_fid_hash_ops,
557 .nsd_type = LDLM_NS_TYPE_MDT,
560 .nsd_hops = &ldlm_ns_fid_hash_ops,
563 .nsd_type = LDLM_NS_TYPE_OSC,
566 .nsd_hops = &ldlm_ns_hash_ops,
569 .nsd_type = LDLM_NS_TYPE_OST,
572 .nsd_hops = &ldlm_ns_hash_ops,
575 .nsd_type = LDLM_NS_TYPE_MGC,
578 .nsd_hops = &ldlm_ns_hash_ops,
581 .nsd_type = LDLM_NS_TYPE_MGT,
584 .nsd_hops = &ldlm_ns_hash_ops,
587 .nsd_type = LDLM_NS_TYPE_UNKNOWN,
592 * Create and initialize new empty namespace.
594 struct ldlm_namespace *ldlm_namespace_new(struct obd_device *obd, char *name,
597 ldlm_ns_type_t ns_type)
599 struct ldlm_namespace *ns = NULL;
600 struct ldlm_ns_bucket *nsb;
601 ldlm_ns_hash_def_t *nsd;
607 LASSERT(obd != NULL);
611 CERROR("ldlm_get_ref failed: %d\n", rc);
615 for (idx = 0;;idx++) {
616 nsd = &ldlm_ns_hash_defs[idx];
617 if (nsd->nsd_type == LDLM_NS_TYPE_UNKNOWN) {
618 CERROR("Unknown type %d for ns %s\n", ns_type, name);
622 if (nsd->nsd_type == ns_type)
630 ns->ns_rs_hash = cfs_hash_create(name,
631 nsd->nsd_all_bits, nsd->nsd_all_bits,
632 nsd->nsd_bkt_bits, sizeof(*nsb),
638 CFS_HASH_SPIN_BKTLOCK |
639 CFS_HASH_NO_ITEMREF);
640 if (ns->ns_rs_hash == NULL)
643 cfs_hash_for_each_bucket(ns->ns_rs_hash, &bd, idx) {
644 nsb = cfs_hash_bd_extra_get(ns->ns_rs_hash, &bd);
645 at_init(&nsb->nsb_at_estimate, ldlm_enqueue_min, 0);
646 nsb->nsb_namespace = ns;
650 ns->ns_appetite = apt;
651 ns->ns_client = client;
653 CFS_INIT_LIST_HEAD(&ns->ns_list_chain);
654 CFS_INIT_LIST_HEAD(&ns->ns_unused_list);
655 spin_lock_init(&ns->ns_lock);
656 cfs_atomic_set(&ns->ns_bref, 0);
657 cfs_waitq_init(&ns->ns_waitq);
659 ns->ns_max_nolock_size = NS_DEFAULT_MAX_NOLOCK_BYTES;
660 ns->ns_contention_time = NS_DEFAULT_CONTENTION_SECONDS;
661 ns->ns_contended_locks = NS_DEFAULT_CONTENDED_LOCKS;
663 ns->ns_max_parallel_ast = LDLM_DEFAULT_PARALLEL_AST_LIMIT;
664 ns->ns_nr_unused = 0;
665 ns->ns_max_unused = LDLM_DEFAULT_LRU_SIZE;
666 ns->ns_max_age = LDLM_DEFAULT_MAX_ALIVE;
667 ns->ns_ctime_age_limit = LDLM_CTIME_AGE_LIMIT;
669 ns->ns_orig_connect_flags = 0;
670 ns->ns_connect_flags = 0;
672 rc = ldlm_namespace_proc_register(ns);
674 CERROR("Can't initialize ns proc, rc %d\n", rc);
678 idx = cfs_atomic_read(ldlm_namespace_nr(client));
679 rc = ldlm_pool_init(&ns->ns_pool, ns, idx, client);
681 CERROR("Can't initialize lock pool, rc %d\n", rc);
685 ldlm_namespace_register(ns, client);
688 ldlm_namespace_proc_unregister(ns);
689 ldlm_namespace_cleanup(ns, 0);
691 cfs_hash_putref(ns->ns_rs_hash);
698 EXPORT_SYMBOL(ldlm_namespace_new);
700 extern struct ldlm_lock *ldlm_lock_get(struct ldlm_lock *lock);
703 * Cancel and destroy all locks on a resource.
705 * If flags contains FL_LOCAL_ONLY, don't try to tell the server, just
706 * clean up. This is currently only used for recovery, and we make
707 * certain assumptions as a result--notably, that we shouldn't cancel
710 static void cleanup_resource(struct ldlm_resource *res, cfs_list_t *q,
714 int rc = 0, client = ns_is_client(ldlm_res_to_ns(res));
715 bool local_only = !!(flags & LDLM_FL_LOCAL_ONLY);
718 struct ldlm_lock *lock = NULL;
720 /* First, we look for non-cleaned-yet lock
721 * all cleaned locks are marked by CLEANED flag. */
723 cfs_list_for_each(tmp, q) {
724 lock = cfs_list_entry(tmp, struct ldlm_lock,
726 if (lock->l_flags & LDLM_FL_CLEANED) {
731 lock->l_flags |= LDLM_FL_CLEANED;
740 /* Set CBPENDING so nothing in the cancellation path
741 * can match this lock. */
742 lock->l_flags |= LDLM_FL_CBPENDING;
743 lock->l_flags |= LDLM_FL_FAILED;
744 lock->l_flags |= flags;
746 /* ... without sending a CANCEL message for local_only. */
748 lock->l_flags |= LDLM_FL_LOCAL_ONLY;
750 if (local_only && (lock->l_readers || lock->l_writers)) {
751 /* This is a little bit gross, but much better than the
752 * alternative: pretend that we got a blocking AST from
753 * the server, so that when the lock is decref'd, it
754 * will go away ... */
756 LDLM_DEBUG(lock, "setting FL_LOCAL_ONLY");
757 if (lock->l_completion_ast)
758 lock->l_completion_ast(lock, 0, NULL);
759 LDLM_LOCK_RELEASE(lock);
764 struct lustre_handle lockh;
767 ldlm_lock2handle(lock, &lockh);
768 rc = ldlm_cli_cancel(&lockh);
770 CERROR("ldlm_cli_cancel: %d\n", rc);
772 ldlm_resource_unlink_lock(lock);
774 LDLM_DEBUG(lock, "Freeing a lock still held by a "
776 ldlm_lock_destroy(lock);
778 LDLM_LOCK_RELEASE(lock);
782 static int ldlm_resource_clean(cfs_hash_t *hs, cfs_hash_bd_t *bd,
783 cfs_hlist_node_t *hnode, void *arg)
785 struct ldlm_resource *res = cfs_hash_object(hs, hnode);
786 __u64 flags = *(__u64 *)arg;
788 cleanup_resource(res, &res->lr_granted, flags);
789 cleanup_resource(res, &res->lr_converting, flags);
790 cleanup_resource(res, &res->lr_waiting, flags);
795 static int ldlm_resource_complain(cfs_hash_t *hs, cfs_hash_bd_t *bd,
796 cfs_hlist_node_t *hnode, void *arg)
798 struct ldlm_resource *res = cfs_hash_object(hs, hnode);
801 CERROR("Namespace %s resource refcount nonzero "
802 "(%d) after lock cleanup; forcing "
804 ldlm_ns_name(ldlm_res_to_ns(res)),
805 cfs_atomic_read(&res->lr_refcount) - 1);
807 CERROR("Resource: %p ("LPU64"/"LPU64"/"LPU64"/"
808 LPU64") (rc: %d)\n", res,
809 res->lr_name.name[0], res->lr_name.name[1],
810 res->lr_name.name[2], res->lr_name.name[3],
811 cfs_atomic_read(&res->lr_refcount) - 1);
813 ldlm_resource_dump(D_ERROR, res);
819 * Cancel and destroy all locks in the namespace.
821 * Typically used during evictions when server notified client that it was
822 * evicted and all of its state needs to be destroyed.
823 * Also used during shutdown.
825 int ldlm_namespace_cleanup(struct ldlm_namespace *ns, __u64 flags)
828 CDEBUG(D_INFO, "NULL ns, skipping cleanup\n");
832 cfs_hash_for_each_nolock(ns->ns_rs_hash, ldlm_resource_clean, &flags);
833 cfs_hash_for_each_nolock(ns->ns_rs_hash, ldlm_resource_complain, NULL);
836 EXPORT_SYMBOL(ldlm_namespace_cleanup);
839 * Attempts to free namespace.
841 * Only used when namespace goes away, like during an unmount.
843 static int __ldlm_namespace_free(struct ldlm_namespace *ns, int force)
847 /* At shutdown time, don't call the cancellation callback */
848 ldlm_namespace_cleanup(ns, force ? LDLM_FL_LOCAL_ONLY : 0);
850 if (cfs_atomic_read(&ns->ns_bref) > 0) {
851 struct l_wait_info lwi = LWI_INTR(LWI_ON_SIGNAL_NOOP, NULL);
854 "dlm namespace %s free waiting on refcount %d\n",
855 ldlm_ns_name(ns), cfs_atomic_read(&ns->ns_bref));
858 lwi = LWI_TIMEOUT(obd_timeout * CFS_HZ / 4, NULL, NULL);
860 rc = l_wait_event(ns->ns_waitq,
861 cfs_atomic_read(&ns->ns_bref) == 0, &lwi);
863 /* Forced cleanups should be able to reclaim all references,
864 * so it's safe to wait forever... we can't leak locks... */
865 if (force && rc == -ETIMEDOUT) {
866 LCONSOLE_ERROR("Forced cleanup waiting for %s "
867 "namespace with %d resources in use, "
868 "(rc=%d)\n", ldlm_ns_name(ns),
869 cfs_atomic_read(&ns->ns_bref), rc);
870 GOTO(force_wait, rc);
873 if (cfs_atomic_read(&ns->ns_bref)) {
874 LCONSOLE_ERROR("Cleanup waiting for %s namespace "
875 "with %d resources in use, (rc=%d)\n",
877 cfs_atomic_read(&ns->ns_bref), rc);
878 RETURN(ELDLM_NAMESPACE_EXISTS);
880 CDEBUG(D_DLMTRACE, "dlm namespace %s free done waiting\n",
888 * Performs various cleanups for passed \a ns to make it drop refc and be
889 * ready for freeing. Waits for refc == 0.
891 * The following is done:
892 * (0) Unregister \a ns from its list to make inaccessible for potential
893 * users like pools thread and others;
894 * (1) Clear all locks in \a ns.
896 void ldlm_namespace_free_prior(struct ldlm_namespace *ns,
897 struct obd_import *imp,
907 spin_lock(&ns->ns_lock);
909 spin_unlock(&ns->ns_lock);
912 * Can fail with -EINTR when force == 0 in which case try harder.
914 rc = __ldlm_namespace_free(ns, force);
915 if (rc != ELDLM_OK) {
917 ptlrpc_disconnect_import(imp, 0);
918 ptlrpc_invalidate_import(imp);
922 * With all requests dropped and the import inactive
923 * we are gaurenteed all reference will be dropped.
925 rc = __ldlm_namespace_free(ns, 1);
932 * Performs freeing memory structures related to \a ns. This is only done
933 * when ldlm_namespce_free_prior() successfully removed all resources
934 * referencing \a ns and its refc == 0.
936 void ldlm_namespace_free_post(struct ldlm_namespace *ns)
944 /* Make sure that nobody can find this ns in its list. */
945 ldlm_namespace_unregister(ns, ns->ns_client);
946 /* Fini pool _before_ parent proc dir is removed. This is important as
947 * ldlm_pool_fini() removes own proc dir which is child to @dir.
948 * Removing it after @dir may cause oops. */
949 ldlm_pool_fini(&ns->ns_pool);
951 ldlm_namespace_proc_unregister(ns);
952 cfs_hash_putref(ns->ns_rs_hash);
953 /* Namespace \a ns should be not on list at this time, otherwise
954 * this will cause issues related to using freed \a ns in poold
956 LASSERT(cfs_list_empty(&ns->ns_list_chain));
963 * Cleanup the resource, and free namespace.
966 * proc1: destroy import
967 * class_disconnect_export(grab cl_sem) ->
968 * -> ldlm_namespace_free ->
969 * -> lprocfs_remove(grab _lprocfs_lock).
970 * proc2: read proc info
971 * lprocfs_fops_read(grab _lprocfs_lock) ->
972 * -> osc_rd_active, etc(grab cl_sem).
974 * So that I have to split the ldlm_namespace_free into two parts - the first
975 * part ldlm_namespace_free_prior is used to cleanup the resource which is
976 * being used; the 2nd part ldlm_namespace_free_post is used to unregister the
977 * lprocfs entries, and then free memory. It will be called w/o cli->cl_sem
980 void ldlm_namespace_free(struct ldlm_namespace *ns,
981 struct obd_import *imp,
984 ldlm_namespace_free_prior(ns, imp, force);
985 ldlm_namespace_free_post(ns);
987 EXPORT_SYMBOL(ldlm_namespace_free);
989 void ldlm_namespace_get(struct ldlm_namespace *ns)
991 cfs_atomic_inc(&ns->ns_bref);
993 EXPORT_SYMBOL(ldlm_namespace_get);
995 void ldlm_namespace_put(struct ldlm_namespace *ns)
997 if (cfs_atomic_dec_and_lock(&ns->ns_bref, &ns->ns_lock)) {
998 cfs_waitq_signal(&ns->ns_waitq);
999 spin_unlock(&ns->ns_lock);
1002 EXPORT_SYMBOL(ldlm_namespace_put);
1004 /** Register \a ns in the list of namespaces */
1005 void ldlm_namespace_register(struct ldlm_namespace *ns, ldlm_side_t client)
1007 mutex_lock(ldlm_namespace_lock(client));
1008 LASSERT(cfs_list_empty(&ns->ns_list_chain));
1009 cfs_list_add(&ns->ns_list_chain, ldlm_namespace_list(client));
1010 cfs_atomic_inc(ldlm_namespace_nr(client));
1011 mutex_unlock(ldlm_namespace_lock(client));
1014 /** Unregister \a ns from the list of namespaces. */
1015 void ldlm_namespace_unregister(struct ldlm_namespace *ns, ldlm_side_t client)
1017 mutex_lock(ldlm_namespace_lock(client));
1018 LASSERT(!cfs_list_empty(&ns->ns_list_chain));
1019 /* Some asserts and possibly other parts of the code are still
1020 * using list_empty(&ns->ns_list_chain). This is why it is
1021 * important to use list_del_init() here. */
1022 cfs_list_del_init(&ns->ns_list_chain);
1023 cfs_atomic_dec(ldlm_namespace_nr(client));
1024 mutex_unlock(ldlm_namespace_lock(client));
1027 /** Should be called with ldlm_namespace_lock(client) taken. */
1028 void ldlm_namespace_move_locked(struct ldlm_namespace *ns, ldlm_side_t client)
1030 LASSERT(!cfs_list_empty(&ns->ns_list_chain));
1031 LASSERT_MUTEX_LOCKED(ldlm_namespace_lock(client));
1032 cfs_list_move_tail(&ns->ns_list_chain, ldlm_namespace_list(client));
1035 /** Should be called with ldlm_namespace_lock(client) taken. */
1036 struct ldlm_namespace *ldlm_namespace_first_locked(ldlm_side_t client)
1038 LASSERT_MUTEX_LOCKED(ldlm_namespace_lock(client));
1039 LASSERT(!cfs_list_empty(ldlm_namespace_list(client)));
1040 return container_of(ldlm_namespace_list(client)->next,
1041 struct ldlm_namespace, ns_list_chain);
1044 /** Create and initialize new resource. */
1045 static struct ldlm_resource *ldlm_resource_new(void)
1047 struct ldlm_resource *res;
1050 OBD_SLAB_ALLOC_PTR_GFP(res, ldlm_resource_slab, CFS_ALLOC_IO);
1054 CFS_INIT_LIST_HEAD(&res->lr_granted);
1055 CFS_INIT_LIST_HEAD(&res->lr_converting);
1056 CFS_INIT_LIST_HEAD(&res->lr_waiting);
1058 /* Initialize interval trees for each lock mode. */
1059 for (idx = 0; idx < LCK_MODE_NUM; idx++) {
1060 res->lr_itree[idx].lit_size = 0;
1061 res->lr_itree[idx].lit_mode = 1 << idx;
1062 res->lr_itree[idx].lit_root = NULL;
1065 cfs_atomic_set(&res->lr_refcount, 1);
1066 spin_lock_init(&res->lr_lock);
1067 lu_ref_init(&res->lr_reference);
1069 /* The creator of the resource must unlock the mutex after LVB
1070 * initialization. */
1071 mutex_init(&res->lr_lvb_mutex);
1072 mutex_lock(&res->lr_lvb_mutex);
1078 * Return a reference to resource with given name, creating it if necessary.
1079 * Args: namespace with ns_lock unlocked
1080 * Locks: takes and releases NS hash-lock and res->lr_lock
1081 * Returns: referenced, unlocked ldlm_resource or NULL
1083 struct ldlm_resource *
1084 ldlm_resource_get(struct ldlm_namespace *ns, struct ldlm_resource *parent,
1085 const struct ldlm_res_id *name, ldlm_type_t type, int create)
1087 cfs_hlist_node_t *hnode;
1088 struct ldlm_resource *res;
1092 LASSERT(ns != NULL);
1093 LASSERT(parent == NULL);
1094 LASSERT(ns->ns_rs_hash != NULL);
1095 LASSERT(name->name[0] != 0);
1097 cfs_hash_bd_get_and_lock(ns->ns_rs_hash, (void *)name, &bd, 0);
1098 hnode = cfs_hash_bd_lookup_locked(ns->ns_rs_hash, &bd, (void *)name);
1099 if (hnode != NULL) {
1100 cfs_hash_bd_unlock(ns->ns_rs_hash, &bd, 0);
1101 res = cfs_hlist_entry(hnode, struct ldlm_resource, lr_hash);
1102 /* Synchronize with regard to resource creation. */
1103 if (ns->ns_lvbo && ns->ns_lvbo->lvbo_init) {
1104 mutex_lock(&res->lr_lvb_mutex);
1105 mutex_unlock(&res->lr_lvb_mutex);
1110 version = cfs_hash_bd_version_get(&bd);
1111 cfs_hash_bd_unlock(ns->ns_rs_hash, &bd, 0);
1116 LASSERTF(type >= LDLM_MIN_TYPE && type < LDLM_MAX_TYPE,
1117 "type: %d\n", type);
1118 res = ldlm_resource_new();
1122 res->lr_ns_bucket = cfs_hash_bd_extra_get(ns->ns_rs_hash, &bd);
1123 res->lr_name = *name;
1124 res->lr_type = type;
1125 res->lr_most_restr = LCK_NL;
1127 cfs_hash_bd_lock(ns->ns_rs_hash, &bd, 1);
1128 hnode = (version == cfs_hash_bd_version_get(&bd)) ? NULL :
1129 cfs_hash_bd_lookup_locked(ns->ns_rs_hash, &bd, (void *)name);
1131 if (hnode != NULL) {
1132 /* Someone won the race and already added the resource. */
1133 cfs_hash_bd_unlock(ns->ns_rs_hash, &bd, 1);
1134 /* Clean lu_ref for failed resource. */
1135 lu_ref_fini(&res->lr_reference);
1136 /* We have taken lr_lvb_mutex. Drop it. */
1137 mutex_unlock(&res->lr_lvb_mutex);
1138 OBD_SLAB_FREE(res, ldlm_resource_slab, sizeof *res);
1140 res = cfs_hlist_entry(hnode, struct ldlm_resource, lr_hash);
1141 /* Synchronize with regard to resource creation. */
1142 if (ns->ns_lvbo && ns->ns_lvbo->lvbo_init) {
1143 mutex_lock(&res->lr_lvb_mutex);
1144 mutex_unlock(&res->lr_lvb_mutex);
1148 /* We won! Let's add the resource. */
1149 cfs_hash_bd_add_locked(ns->ns_rs_hash, &bd, &res->lr_hash);
1150 if (cfs_hash_bd_count_get(&bd) == 1)
1151 ldlm_namespace_get(ns);
1153 cfs_hash_bd_unlock(ns->ns_rs_hash, &bd, 1);
1154 if (ns->ns_lvbo && ns->ns_lvbo->lvbo_init) {
1157 OBD_FAIL_TIMEOUT(OBD_FAIL_LDLM_CREATE_RESOURCE, 2);
1158 rc = ns->ns_lvbo->lvbo_init(res);
1160 CERROR("lvbo_init failed for resource "
1161 LPU64": rc %d\n", name->name[0], rc);
1164 /* We create resource with locked lr_lvb_mutex. */
1165 mutex_unlock(&res->lr_lvb_mutex);
1169 EXPORT_SYMBOL(ldlm_resource_get);
1171 struct ldlm_resource *ldlm_resource_getref(struct ldlm_resource *res)
1173 LASSERT(res != NULL);
1174 LASSERT(res != LP_POISON);
1175 cfs_atomic_inc(&res->lr_refcount);
1176 CDEBUG(D_INFO, "getref res: %p count: %d\n", res,
1177 cfs_atomic_read(&res->lr_refcount));
1181 static void __ldlm_resource_putref_final(cfs_hash_bd_t *bd,
1182 struct ldlm_resource *res)
1184 struct ldlm_ns_bucket *nsb = res->lr_ns_bucket;
1186 if (!cfs_list_empty(&res->lr_granted)) {
1187 ldlm_resource_dump(D_ERROR, res);
1191 if (!cfs_list_empty(&res->lr_converting)) {
1192 ldlm_resource_dump(D_ERROR, res);
1196 if (!cfs_list_empty(&res->lr_waiting)) {
1197 ldlm_resource_dump(D_ERROR, res);
1201 cfs_hash_bd_del_locked(nsb->nsb_namespace->ns_rs_hash,
1203 lu_ref_fini(&res->lr_reference);
1204 if (cfs_hash_bd_count_get(bd) == 0)
1205 ldlm_namespace_put(nsb->nsb_namespace);
1208 /* Returns 1 if the resource was freed, 0 if it remains. */
1209 int ldlm_resource_putref(struct ldlm_resource *res)
1211 struct ldlm_namespace *ns = ldlm_res_to_ns(res);
1214 LASSERT_ATOMIC_GT_LT(&res->lr_refcount, 0, LI_POISON);
1215 CDEBUG(D_INFO, "putref res: %p count: %d\n",
1216 res, cfs_atomic_read(&res->lr_refcount) - 1);
1218 cfs_hash_bd_get(ns->ns_rs_hash, &res->lr_name, &bd);
1219 if (cfs_hash_bd_dec_and_lock(ns->ns_rs_hash, &bd, &res->lr_refcount)) {
1220 __ldlm_resource_putref_final(&bd, res);
1221 cfs_hash_bd_unlock(ns->ns_rs_hash, &bd, 1);
1222 if (ns->ns_lvbo && ns->ns_lvbo->lvbo_free)
1223 ns->ns_lvbo->lvbo_free(res);
1224 OBD_SLAB_FREE(res, ldlm_resource_slab, sizeof *res);
1229 EXPORT_SYMBOL(ldlm_resource_putref);
1231 /* Returns 1 if the resource was freed, 0 if it remains. */
1232 int ldlm_resource_putref_locked(struct ldlm_resource *res)
1234 struct ldlm_namespace *ns = ldlm_res_to_ns(res);
1236 LASSERT_ATOMIC_GT_LT(&res->lr_refcount, 0, LI_POISON);
1237 CDEBUG(D_INFO, "putref res: %p count: %d\n",
1238 res, cfs_atomic_read(&res->lr_refcount) - 1);
1240 if (cfs_atomic_dec_and_test(&res->lr_refcount)) {
1243 cfs_hash_bd_get(ldlm_res_to_ns(res)->ns_rs_hash,
1244 &res->lr_name, &bd);
1245 __ldlm_resource_putref_final(&bd, res);
1246 cfs_hash_bd_unlock(ns->ns_rs_hash, &bd, 1);
1247 /* NB: ns_rs_hash is created with CFS_HASH_NO_ITEMREF,
1248 * so we should never be here while calling cfs_hash_del,
1249 * cfs_hash_for_each_nolock is the only case we can get
1250 * here, which is safe to release cfs_hash_bd_lock.
1252 if (ns->ns_lvbo && ns->ns_lvbo->lvbo_free)
1253 ns->ns_lvbo->lvbo_free(res);
1254 OBD_SLAB_FREE(res, ldlm_resource_slab, sizeof *res);
1256 cfs_hash_bd_lock(ns->ns_rs_hash, &bd, 1);
1263 * Add a lock into a given resource into specified lock list.
1265 void ldlm_resource_add_lock(struct ldlm_resource *res, cfs_list_t *head,
1266 struct ldlm_lock *lock)
1268 check_res_locked(res);
1270 LDLM_DEBUG(lock, "About to add this lock:\n");
1272 if (lock->l_destroyed) {
1273 CDEBUG(D_OTHER, "Lock destroyed, not adding to resource\n");
1277 LASSERT(cfs_list_empty(&lock->l_res_link));
1279 cfs_list_add_tail(&lock->l_res_link, head);
1283 * Insert a lock into resource after specified lock.
1285 * Obtain resource description from the lock we are inserting after.
1287 void ldlm_resource_insert_lock_after(struct ldlm_lock *original,
1288 struct ldlm_lock *new)
1290 struct ldlm_resource *res = original->l_resource;
1292 check_res_locked(res);
1294 ldlm_resource_dump(D_INFO, res);
1295 LDLM_DEBUG(new, "About to insert this lock after %p:\n", original);
1297 if (new->l_destroyed) {
1298 CDEBUG(D_OTHER, "Lock destroyed, not adding to resource\n");
1302 LASSERT(cfs_list_empty(&new->l_res_link));
1304 cfs_list_add(&new->l_res_link, &original->l_res_link);
1308 void ldlm_resource_unlink_lock(struct ldlm_lock *lock)
1310 int type = lock->l_resource->lr_type;
1312 check_res_locked(lock->l_resource);
1313 if (type == LDLM_IBITS || type == LDLM_PLAIN)
1314 ldlm_unlink_lock_skiplist(lock);
1315 else if (type == LDLM_EXTENT)
1316 ldlm_extent_unlink_lock(lock);
1317 cfs_list_del_init(&lock->l_res_link);
1319 EXPORT_SYMBOL(ldlm_resource_unlink_lock);
1321 void ldlm_res2desc(struct ldlm_resource *res, struct ldlm_resource_desc *desc)
1323 desc->lr_type = res->lr_type;
1324 desc->lr_name = res->lr_name;
1328 * Print information about all locks in all namespaces on this node to debug
1331 void ldlm_dump_all_namespaces(ldlm_side_t client, int level)
1335 if (!((libcfs_debug | D_ERROR) & level))
1338 mutex_lock(ldlm_namespace_lock(client));
1340 cfs_list_for_each(tmp, ldlm_namespace_list(client)) {
1341 struct ldlm_namespace *ns;
1342 ns = cfs_list_entry(tmp, struct ldlm_namespace, ns_list_chain);
1343 ldlm_namespace_dump(level, ns);
1346 mutex_unlock(ldlm_namespace_lock(client));
1348 EXPORT_SYMBOL(ldlm_dump_all_namespaces);
1350 static int ldlm_res_hash_dump(cfs_hash_t *hs, cfs_hash_bd_t *bd,
1351 cfs_hlist_node_t *hnode, void *arg)
1353 struct ldlm_resource *res = cfs_hash_object(hs, hnode);
1354 int level = (int)(unsigned long)arg;
1357 ldlm_resource_dump(level, res);
1364 * Print information about all locks in this namespace on this node to debug
1367 void ldlm_namespace_dump(int level, struct ldlm_namespace *ns)
1369 if (!((libcfs_debug | D_ERROR) & level))
1372 CDEBUG(level, "--- Namespace: %s (rc: %d, side: %s)\n",
1373 ldlm_ns_name(ns), cfs_atomic_read(&ns->ns_bref),
1374 ns_is_client(ns) ? "client" : "server");
1376 if (cfs_time_before(cfs_time_current(), ns->ns_next_dump))
1379 cfs_hash_for_each_nolock(ns->ns_rs_hash,
1381 (void *)(unsigned long)level);
1382 spin_lock(&ns->ns_lock);
1383 ns->ns_next_dump = cfs_time_shift(10);
1384 spin_unlock(&ns->ns_lock);
1386 EXPORT_SYMBOL(ldlm_namespace_dump);
1389 * Print information about all locks in this resource to debug log.
1391 void ldlm_resource_dump(int level, struct ldlm_resource *res)
1393 struct ldlm_lock *lock;
1394 unsigned int granted = 0;
1396 CLASSERT(RES_NAME_SIZE == 4);
1398 if (!((libcfs_debug | D_ERROR) & level))
1401 CDEBUG(level, "--- Resource: %p ("LPU64"/"LPU64"/"LPU64"/"LPU64
1402 ") (rc: %d)\n", res, res->lr_name.name[0], res->lr_name.name[1],
1403 res->lr_name.name[2], res->lr_name.name[3],
1404 cfs_atomic_read(&res->lr_refcount));
1406 if (!cfs_list_empty(&res->lr_granted)) {
1407 CDEBUG(level, "Granted locks (in reverse order):\n");
1408 cfs_list_for_each_entry_reverse(lock, &res->lr_granted,
1410 LDLM_DEBUG_LIMIT(level, lock, "###");
1411 if (!(level & D_CANTMASK) &&
1412 ++granted > ldlm_dump_granted_max) {
1413 CDEBUG(level, "only dump %d granted locks to "
1414 "avoid DDOS.\n", granted);
1419 if (!cfs_list_empty(&res->lr_converting)) {
1420 CDEBUG(level, "Converting locks:\n");
1421 cfs_list_for_each_entry(lock, &res->lr_converting, l_res_link)
1422 LDLM_DEBUG_LIMIT(level, lock, "###");
1424 if (!cfs_list_empty(&res->lr_waiting)) {
1425 CDEBUG(level, "Waiting locks:\n");
1426 cfs_list_for_each_entry(lock, &res->lr_waiting, l_res_link)
1427 LDLM_DEBUG_LIMIT(level, lock, "###");