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) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
28 * Use is subject to license terms.
30 * Copyright (c) 2011, 2012, Whamcloud, Inc.
33 * This file is part of Lustre, http://www.lustre.org/
34 * Lustre is a trademark of Sun Microsystems, Inc.
38 * Author: Nikita Danilov <nikita.danilov@sun.com>
41 #define DEBUG_SUBSYSTEM S_CLASS
43 #include <obd_class.h>
44 #include <obd_support.h>
45 #include <lustre_fid.h>
46 #include <libcfs/list.h>
47 /* lu_time_global_{init,fini}() */
50 #include <cl_object.h>
51 #include "cl_internal.h"
53 /** Lock class of cl_lock::cll_guard */
54 static cfs_lock_class_key_t cl_lock_guard_class;
55 static cfs_mem_cache_t *cl_lock_kmem;
57 static struct lu_kmem_descr cl_lock_caches[] = {
59 .ckd_cache = &cl_lock_kmem,
60 .ckd_name = "cl_lock_kmem",
61 .ckd_size = sizeof (struct cl_lock)
69 * Basic lock invariant that is maintained at all times. Caller either has a
70 * reference to \a lock, or somehow assures that \a lock cannot be freed.
72 * \see cl_lock_invariant()
74 static int cl_lock_invariant_trusted(const struct lu_env *env,
75 const struct cl_lock *lock)
77 return ergo(lock->cll_state == CLS_FREEING, lock->cll_holds == 0) &&
78 cfs_atomic_read(&lock->cll_ref) >= lock->cll_holds &&
79 lock->cll_holds >= lock->cll_users &&
80 lock->cll_holds >= 0 &&
81 lock->cll_users >= 0 &&
86 * Stronger lock invariant, checking that caller has a reference on a lock.
88 * \see cl_lock_invariant_trusted()
90 static int cl_lock_invariant(const struct lu_env *env,
91 const struct cl_lock *lock)
95 result = cfs_atomic_read(&lock->cll_ref) > 0 &&
96 cl_lock_invariant_trusted(env, lock);
97 if (!result && env != NULL)
98 CL_LOCK_DEBUG(D_ERROR, env, lock, "invariant broken");
103 * Returns lock "nesting": 0 for a top-lock and 1 for a sub-lock.
105 static enum clt_nesting_level cl_lock_nesting(const struct cl_lock *lock)
107 return cl_object_header(lock->cll_descr.cld_obj)->coh_nesting;
111 * Returns a set of counters for this lock, depending on a lock nesting.
113 static struct cl_thread_counters *cl_lock_counters(const struct lu_env *env,
114 const struct cl_lock *lock)
116 struct cl_thread_info *info;
117 enum clt_nesting_level nesting;
119 info = cl_env_info(env);
120 nesting = cl_lock_nesting(lock);
121 LASSERT(nesting < ARRAY_SIZE(info->clt_counters));
122 return &info->clt_counters[nesting];
125 static void cl_lock_trace0(int level, const struct lu_env *env,
126 const char *prefix, const struct cl_lock *lock,
127 const char *func, const int line)
129 struct cl_object_header *h = cl_object_header(lock->cll_descr.cld_obj);
130 CDEBUG(level, "%s: %p@(%d %p %d %d %d %d %d %lx)"
131 "(%p/%d/%d) at %s():%d\n",
132 prefix, lock, cfs_atomic_read(&lock->cll_ref),
133 lock->cll_guarder, lock->cll_depth,
134 lock->cll_state, lock->cll_error, lock->cll_holds,
135 lock->cll_users, lock->cll_flags,
136 env, h->coh_nesting, cl_lock_nr_mutexed(env),
139 #define cl_lock_trace(level, env, prefix, lock) \
140 cl_lock_trace0(level, env, prefix, lock, __FUNCTION__, __LINE__)
142 #define RETIP ((unsigned long)__builtin_return_address(0))
144 #ifdef CONFIG_LOCKDEP
145 static cfs_lock_class_key_t cl_lock_key;
147 static void cl_lock_lockdep_init(struct cl_lock *lock)
149 lockdep_set_class_and_name(lock, &cl_lock_key, "EXT");
152 static void cl_lock_lockdep_acquire(const struct lu_env *env,
153 struct cl_lock *lock, __u32 enqflags)
155 cl_lock_counters(env, lock)->ctc_nr_locks_acquired++;
156 #ifdef HAVE_LOCK_MAP_ACQUIRE
157 lock_map_acquire(&lock->dep_map);
158 #else /* HAVE_LOCK_MAP_ACQUIRE */
159 lock_acquire(&lock->dep_map, !!(enqflags & CEF_ASYNC),
160 /* try: */ 0, lock->cll_descr.cld_mode <= CLM_READ,
161 /* check: */ 2, RETIP);
162 #endif /* HAVE_LOCK_MAP_ACQUIRE */
165 static void cl_lock_lockdep_release(const struct lu_env *env,
166 struct cl_lock *lock)
168 cl_lock_counters(env, lock)->ctc_nr_locks_acquired--;
169 lock_release(&lock->dep_map, 0, RETIP);
172 #else /* !CONFIG_LOCKDEP */
174 static void cl_lock_lockdep_init(struct cl_lock *lock)
176 static void cl_lock_lockdep_acquire(const struct lu_env *env,
177 struct cl_lock *lock, __u32 enqflags)
179 static void cl_lock_lockdep_release(const struct lu_env *env,
180 struct cl_lock *lock)
183 #endif /* !CONFIG_LOCKDEP */
186 * Adds lock slice to the compound lock.
188 * This is called by cl_object_operations::coo_lock_init() methods to add a
189 * per-layer state to the lock. New state is added at the end of
190 * cl_lock::cll_layers list, that is, it is at the bottom of the stack.
192 * \see cl_req_slice_add(), cl_page_slice_add(), cl_io_slice_add()
194 void cl_lock_slice_add(struct cl_lock *lock, struct cl_lock_slice *slice,
195 struct cl_object *obj,
196 const struct cl_lock_operations *ops)
199 slice->cls_lock = lock;
200 cfs_list_add_tail(&slice->cls_linkage, &lock->cll_layers);
201 slice->cls_obj = obj;
202 slice->cls_ops = ops;
205 EXPORT_SYMBOL(cl_lock_slice_add);
208 * Returns true iff a lock with the mode \a has provides at least the same
209 * guarantees as a lock with the mode \a need.
211 int cl_lock_mode_match(enum cl_lock_mode has, enum cl_lock_mode need)
213 LINVRNT(need == CLM_READ || need == CLM_WRITE ||
214 need == CLM_PHANTOM || need == CLM_GROUP);
215 LINVRNT(has == CLM_READ || has == CLM_WRITE ||
216 has == CLM_PHANTOM || has == CLM_GROUP);
217 CLASSERT(CLM_PHANTOM < CLM_READ);
218 CLASSERT(CLM_READ < CLM_WRITE);
219 CLASSERT(CLM_WRITE < CLM_GROUP);
221 if (has != CLM_GROUP)
226 EXPORT_SYMBOL(cl_lock_mode_match);
229 * Returns true iff extent portions of lock descriptions match.
231 int cl_lock_ext_match(const struct cl_lock_descr *has,
232 const struct cl_lock_descr *need)
235 has->cld_start <= need->cld_start &&
236 has->cld_end >= need->cld_end &&
237 cl_lock_mode_match(has->cld_mode, need->cld_mode) &&
238 (has->cld_mode != CLM_GROUP || has->cld_gid == need->cld_gid);
240 EXPORT_SYMBOL(cl_lock_ext_match);
243 * Returns true iff a lock with the description \a has provides at least the
244 * same guarantees as a lock with the description \a need.
246 int cl_lock_descr_match(const struct cl_lock_descr *has,
247 const struct cl_lock_descr *need)
250 cl_object_same(has->cld_obj, need->cld_obj) &&
251 cl_lock_ext_match(has, need);
253 EXPORT_SYMBOL(cl_lock_descr_match);
255 static void cl_lock_free(const struct lu_env *env, struct cl_lock *lock)
257 struct cl_object *obj = lock->cll_descr.cld_obj;
259 LINVRNT(!cl_lock_is_mutexed(lock));
262 cl_lock_trace(D_DLMTRACE, env, "free lock", lock);
264 while (!cfs_list_empty(&lock->cll_layers)) {
265 struct cl_lock_slice *slice;
267 slice = cfs_list_entry(lock->cll_layers.next,
268 struct cl_lock_slice, cls_linkage);
269 cfs_list_del_init(lock->cll_layers.next);
270 slice->cls_ops->clo_fini(env, slice);
272 cfs_atomic_dec(&cl_object_site(obj)->cs_locks.cs_total);
273 cfs_atomic_dec(&cl_object_site(obj)->cs_locks_state[lock->cll_state]);
274 lu_object_ref_del_at(&obj->co_lu, lock->cll_obj_ref, "cl_lock", lock);
275 cl_object_put(env, obj);
276 lu_ref_fini(&lock->cll_reference);
277 lu_ref_fini(&lock->cll_holders);
278 cfs_mutex_destroy(&lock->cll_guard);
279 OBD_SLAB_FREE_PTR(lock, cl_lock_kmem);
284 * Releases a reference on a lock.
286 * When last reference is released, lock is returned to the cache, unless it
287 * is in cl_lock_state::CLS_FREEING state, in which case it is destroyed
290 * \see cl_object_put(), cl_page_put()
292 void cl_lock_put(const struct lu_env *env, struct cl_lock *lock)
294 struct cl_object *obj;
295 struct cl_site *site;
297 LINVRNT(cl_lock_invariant(env, lock));
299 obj = lock->cll_descr.cld_obj;
300 LINVRNT(obj != NULL);
301 site = cl_object_site(obj);
303 CDEBUG(D_TRACE, "releasing reference: %d %p %lu\n",
304 cfs_atomic_read(&lock->cll_ref), lock, RETIP);
306 if (cfs_atomic_dec_and_test(&lock->cll_ref)) {
307 if (lock->cll_state == CLS_FREEING) {
308 LASSERT(cfs_list_empty(&lock->cll_linkage));
309 cl_lock_free(env, lock);
311 cfs_atomic_dec(&site->cs_locks.cs_busy);
315 EXPORT_SYMBOL(cl_lock_put);
318 * Acquires an additional reference to a lock.
320 * This can be called only by caller already possessing a reference to \a
323 * \see cl_object_get(), cl_page_get()
325 void cl_lock_get(struct cl_lock *lock)
327 LINVRNT(cl_lock_invariant(NULL, lock));
328 CDEBUG(D_TRACE, "acquiring reference: %d %p %lu\n",
329 cfs_atomic_read(&lock->cll_ref), lock, RETIP);
330 cfs_atomic_inc(&lock->cll_ref);
332 EXPORT_SYMBOL(cl_lock_get);
335 * Acquires a reference to a lock.
337 * This is much like cl_lock_get(), except that this function can be used to
338 * acquire initial reference to the cached lock. Caller has to deal with all
339 * possible races. Use with care!
341 * \see cl_page_get_trust()
343 void cl_lock_get_trust(struct cl_lock *lock)
345 struct cl_site *site = cl_object_site(lock->cll_descr.cld_obj);
347 CDEBUG(D_TRACE, "acquiring trusted reference: %d %p %lu\n",
348 cfs_atomic_read(&lock->cll_ref), lock, RETIP);
349 if (cfs_atomic_inc_return(&lock->cll_ref) == 1)
350 cfs_atomic_inc(&site->cs_locks.cs_busy);
352 EXPORT_SYMBOL(cl_lock_get_trust);
355 * Helper function destroying the lock that wasn't completely initialized.
357 * Other threads can acquire references to the top-lock through its
358 * sub-locks. Hence, it cannot be cl_lock_free()-ed immediately.
360 static void cl_lock_finish(const struct lu_env *env, struct cl_lock *lock)
362 cl_lock_mutex_get(env, lock);
363 cl_lock_cancel(env, lock);
364 cl_lock_delete(env, lock);
365 cl_lock_mutex_put(env, lock);
366 cl_lock_put(env, lock);
369 static struct cl_lock *cl_lock_alloc(const struct lu_env *env,
370 struct cl_object *obj,
371 const struct cl_io *io,
372 const struct cl_lock_descr *descr)
374 struct cl_lock *lock;
375 struct lu_object_header *head;
376 struct cl_site *site = cl_object_site(obj);
379 OBD_SLAB_ALLOC_PTR_GFP(lock, cl_lock_kmem, CFS_ALLOC_IO);
381 cfs_atomic_set(&lock->cll_ref, 1);
382 lock->cll_descr = *descr;
383 lock->cll_state = CLS_NEW;
385 lock->cll_obj_ref = lu_object_ref_add(&obj->co_lu,
387 CFS_INIT_LIST_HEAD(&lock->cll_layers);
388 CFS_INIT_LIST_HEAD(&lock->cll_linkage);
389 CFS_INIT_LIST_HEAD(&lock->cll_inclosure);
390 lu_ref_init(&lock->cll_reference);
391 lu_ref_init(&lock->cll_holders);
392 cfs_mutex_init(&lock->cll_guard);
393 cfs_lockdep_set_class(&lock->cll_guard, &cl_lock_guard_class);
394 cfs_waitq_init(&lock->cll_wq);
395 head = obj->co_lu.lo_header;
396 cfs_atomic_inc(&site->cs_locks_state[CLS_NEW]);
397 cfs_atomic_inc(&site->cs_locks.cs_total);
398 cfs_atomic_inc(&site->cs_locks.cs_created);
399 cl_lock_lockdep_init(lock);
400 cfs_list_for_each_entry(obj, &head->loh_layers,
404 err = obj->co_ops->coo_lock_init(env, obj, lock, io);
406 cl_lock_finish(env, lock);
412 lock = ERR_PTR(-ENOMEM);
417 * Transfer the lock into INTRANSIT state and return the original state.
419 * \pre state: CLS_CACHED, CLS_HELD or CLS_ENQUEUED
420 * \post state: CLS_INTRANSIT
423 enum cl_lock_state cl_lock_intransit(const struct lu_env *env,
424 struct cl_lock *lock)
426 enum cl_lock_state state = lock->cll_state;
428 LASSERT(cl_lock_is_mutexed(lock));
429 LASSERT(state != CLS_INTRANSIT);
430 LASSERTF(state >= CLS_ENQUEUED && state <= CLS_CACHED,
431 "Malformed lock state %d.\n", state);
433 cl_lock_state_set(env, lock, CLS_INTRANSIT);
434 lock->cll_intransit_owner = cfs_current();
435 cl_lock_hold_add(env, lock, "intransit", cfs_current());
438 EXPORT_SYMBOL(cl_lock_intransit);
441 * Exit the intransit state and restore the lock state to the original state
443 void cl_lock_extransit(const struct lu_env *env, struct cl_lock *lock,
444 enum cl_lock_state state)
446 LASSERT(cl_lock_is_mutexed(lock));
447 LASSERT(lock->cll_state == CLS_INTRANSIT);
448 LASSERT(state != CLS_INTRANSIT);
449 LASSERT(lock->cll_intransit_owner == cfs_current());
451 lock->cll_intransit_owner = NULL;
452 cl_lock_state_set(env, lock, state);
453 cl_lock_unhold(env, lock, "intransit", cfs_current());
455 EXPORT_SYMBOL(cl_lock_extransit);
458 * Checking whether the lock is intransit state
460 int cl_lock_is_intransit(struct cl_lock *lock)
462 LASSERT(cl_lock_is_mutexed(lock));
463 return lock->cll_state == CLS_INTRANSIT &&
464 lock->cll_intransit_owner != cfs_current();
466 EXPORT_SYMBOL(cl_lock_is_intransit);
468 * Returns true iff lock is "suitable" for given io. E.g., locks acquired by
469 * truncate and O_APPEND cannot be reused for read/non-append-write, as they
470 * cover multiple stripes and can trigger cascading timeouts.
472 static int cl_lock_fits_into(const struct lu_env *env,
473 const struct cl_lock *lock,
474 const struct cl_lock_descr *need,
475 const struct cl_io *io)
477 const struct cl_lock_slice *slice;
479 LINVRNT(cl_lock_invariant_trusted(env, lock));
481 cfs_list_for_each_entry(slice, &lock->cll_layers, cls_linkage) {
482 if (slice->cls_ops->clo_fits_into != NULL &&
483 !slice->cls_ops->clo_fits_into(env, slice, need, io))
489 static struct cl_lock *cl_lock_lookup(const struct lu_env *env,
490 struct cl_object *obj,
491 const struct cl_io *io,
492 const struct cl_lock_descr *need)
494 struct cl_lock *lock;
495 struct cl_object_header *head;
496 struct cl_site *site;
500 head = cl_object_header(obj);
501 site = cl_object_site(obj);
502 LINVRNT_SPIN_LOCKED(&head->coh_lock_guard);
503 cfs_atomic_inc(&site->cs_locks.cs_lookup);
504 cfs_list_for_each_entry(lock, &head->coh_locks, cll_linkage) {
507 matched = cl_lock_ext_match(&lock->cll_descr, need) &&
508 lock->cll_state < CLS_FREEING &&
509 lock->cll_error == 0 &&
510 !(lock->cll_flags & CLF_CANCELLED) &&
511 cl_lock_fits_into(env, lock, need, io);
512 CDEBUG(D_DLMTRACE, "has: "DDESCR"(%d) need: "DDESCR": %d\n",
513 PDESCR(&lock->cll_descr), lock->cll_state, PDESCR(need),
516 cl_lock_get_trust(lock);
517 cfs_atomic_inc(&cl_object_site(obj)->cs_locks.cs_hit);
525 * Returns a lock matching description \a need.
527 * This is the main entry point into the cl_lock caching interface. First, a
528 * cache (implemented as a per-object linked list) is consulted. If lock is
529 * found there, it is returned immediately. Otherwise new lock is allocated
530 * and returned. In any case, additional reference to lock is acquired.
532 * \see cl_object_find(), cl_page_find()
534 static struct cl_lock *cl_lock_find(const struct lu_env *env,
535 const struct cl_io *io,
536 const struct cl_lock_descr *need)
538 struct cl_object_header *head;
539 struct cl_object *obj;
540 struct cl_lock *lock;
541 struct cl_site *site;
546 head = cl_object_header(obj);
547 site = cl_object_site(obj);
549 cfs_spin_lock(&head->coh_lock_guard);
550 lock = cl_lock_lookup(env, obj, io, need);
551 cfs_spin_unlock(&head->coh_lock_guard);
554 lock = cl_lock_alloc(env, obj, io, need);
556 struct cl_lock *ghost;
558 cfs_spin_lock(&head->coh_lock_guard);
559 ghost = cl_lock_lookup(env, obj, io, need);
561 cfs_list_add_tail(&lock->cll_linkage,
563 cfs_spin_unlock(&head->coh_lock_guard);
564 cfs_atomic_inc(&site->cs_locks.cs_busy);
566 cfs_spin_unlock(&head->coh_lock_guard);
568 * Other threads can acquire references to the
569 * top-lock through its sub-locks. Hence, it
570 * cannot be cl_lock_free()-ed immediately.
572 cl_lock_finish(env, lock);
581 * Returns existing lock matching given description. This is similar to
582 * cl_lock_find() except that no new lock is created, and returned lock is
583 * guaranteed to be in enum cl_lock_state::CLS_HELD state.
585 struct cl_lock *cl_lock_peek(const struct lu_env *env, const struct cl_io *io,
586 const struct cl_lock_descr *need,
587 const char *scope, const void *source)
589 struct cl_object_header *head;
590 struct cl_object *obj;
591 struct cl_lock *lock;
594 head = cl_object_header(obj);
596 cfs_spin_lock(&head->coh_lock_guard);
597 lock = cl_lock_lookup(env, obj, io, need);
598 cfs_spin_unlock(&head->coh_lock_guard);
603 cl_lock_mutex_get(env, lock);
604 if (lock->cll_state == CLS_INTRANSIT)
605 cl_lock_state_wait(env, lock); /* Don't care return value. */
606 cl_lock_hold_add(env, lock, scope, source);
607 cl_lock_user_add(env, lock);
608 if (lock->cll_state == CLS_CACHED)
609 cl_use_try(env, lock, 1);
610 if (lock->cll_state == CLS_HELD) {
611 cl_lock_mutex_put(env, lock);
612 cl_lock_lockdep_acquire(env, lock, 0);
613 cl_lock_put(env, lock);
615 cl_unuse_try(env, lock);
616 cl_lock_unhold(env, lock, scope, source);
617 cl_lock_mutex_put(env, lock);
618 cl_lock_put(env, lock);
624 EXPORT_SYMBOL(cl_lock_peek);
627 * Returns a slice within a lock, corresponding to the given layer in the
632 const struct cl_lock_slice *cl_lock_at(const struct cl_lock *lock,
633 const struct lu_device_type *dtype)
635 const struct cl_lock_slice *slice;
637 LINVRNT(cl_lock_invariant_trusted(NULL, lock));
640 cfs_list_for_each_entry(slice, &lock->cll_layers, cls_linkage) {
641 if (slice->cls_obj->co_lu.lo_dev->ld_type == dtype)
646 EXPORT_SYMBOL(cl_lock_at);
648 static void cl_lock_mutex_tail(const struct lu_env *env, struct cl_lock *lock)
650 struct cl_thread_counters *counters;
652 counters = cl_lock_counters(env, lock);
654 counters->ctc_nr_locks_locked++;
655 lu_ref_add(&counters->ctc_locks_locked, "cll_guard", lock);
656 cl_lock_trace(D_TRACE, env, "got mutex", lock);
660 * Locks cl_lock object.
662 * This is used to manipulate cl_lock fields, and to serialize state
663 * transitions in the lock state machine.
665 * \post cl_lock_is_mutexed(lock)
667 * \see cl_lock_mutex_put()
669 void cl_lock_mutex_get(const struct lu_env *env, struct cl_lock *lock)
671 LINVRNT(cl_lock_invariant(env, lock));
673 if (lock->cll_guarder == cfs_current()) {
674 LINVRNT(cl_lock_is_mutexed(lock));
675 LINVRNT(lock->cll_depth > 0);
677 struct cl_object_header *hdr;
678 struct cl_thread_info *info;
681 LINVRNT(lock->cll_guarder != cfs_current());
682 hdr = cl_object_header(lock->cll_descr.cld_obj);
684 * Check that mutices are taken in the bottom-to-top order.
686 info = cl_env_info(env);
687 for (i = 0; i < hdr->coh_nesting; ++i)
688 LASSERT(info->clt_counters[i].ctc_nr_locks_locked == 0);
689 cfs_mutex_lock_nested(&lock->cll_guard, hdr->coh_nesting);
690 lock->cll_guarder = cfs_current();
691 LINVRNT(lock->cll_depth == 0);
693 cl_lock_mutex_tail(env, lock);
695 EXPORT_SYMBOL(cl_lock_mutex_get);
698 * Try-locks cl_lock object.
700 * \retval 0 \a lock was successfully locked
702 * \retval -EBUSY \a lock cannot be locked right now
704 * \post ergo(result == 0, cl_lock_is_mutexed(lock))
706 * \see cl_lock_mutex_get()
708 int cl_lock_mutex_try(const struct lu_env *env, struct cl_lock *lock)
712 LINVRNT(cl_lock_invariant_trusted(env, lock));
716 if (lock->cll_guarder == cfs_current()) {
717 LINVRNT(lock->cll_depth > 0);
718 cl_lock_mutex_tail(env, lock);
719 } else if (cfs_mutex_trylock(&lock->cll_guard)) {
720 LINVRNT(lock->cll_depth == 0);
721 lock->cll_guarder = cfs_current();
722 cl_lock_mutex_tail(env, lock);
727 EXPORT_SYMBOL(cl_lock_mutex_try);
730 {* Unlocks cl_lock object.
732 * \pre cl_lock_is_mutexed(lock)
734 * \see cl_lock_mutex_get()
736 void cl_lock_mutex_put(const struct lu_env *env, struct cl_lock *lock)
738 struct cl_thread_counters *counters;
740 LINVRNT(cl_lock_invariant(env, lock));
741 LINVRNT(cl_lock_is_mutexed(lock));
742 LINVRNT(lock->cll_guarder == cfs_current());
743 LINVRNT(lock->cll_depth > 0);
745 counters = cl_lock_counters(env, lock);
746 LINVRNT(counters->ctc_nr_locks_locked > 0);
748 cl_lock_trace(D_TRACE, env, "put mutex", lock);
749 lu_ref_del(&counters->ctc_locks_locked, "cll_guard", lock);
750 counters->ctc_nr_locks_locked--;
751 if (--lock->cll_depth == 0) {
752 lock->cll_guarder = NULL;
753 cfs_mutex_unlock(&lock->cll_guard);
756 EXPORT_SYMBOL(cl_lock_mutex_put);
759 * Returns true iff lock's mutex is owned by the current thread.
761 int cl_lock_is_mutexed(struct cl_lock *lock)
763 return lock->cll_guarder == cfs_current();
765 EXPORT_SYMBOL(cl_lock_is_mutexed);
768 * Returns number of cl_lock mutices held by the current thread (environment).
770 int cl_lock_nr_mutexed(const struct lu_env *env)
772 struct cl_thread_info *info;
777 * NOTE: if summation across all nesting levels (currently 2) proves
778 * too expensive, a summary counter can be added to
779 * struct cl_thread_info.
781 info = cl_env_info(env);
782 for (i = 0, locked = 0; i < ARRAY_SIZE(info->clt_counters); ++i)
783 locked += info->clt_counters[i].ctc_nr_locks_locked;
786 EXPORT_SYMBOL(cl_lock_nr_mutexed);
788 static void cl_lock_cancel0(const struct lu_env *env, struct cl_lock *lock)
790 LINVRNT(cl_lock_is_mutexed(lock));
791 LINVRNT(cl_lock_invariant(env, lock));
793 if (!(lock->cll_flags & CLF_CANCELLED)) {
794 const struct cl_lock_slice *slice;
796 lock->cll_flags |= CLF_CANCELLED;
797 cfs_list_for_each_entry_reverse(slice, &lock->cll_layers,
799 if (slice->cls_ops->clo_cancel != NULL)
800 slice->cls_ops->clo_cancel(env, slice);
806 static void cl_lock_delete0(const struct lu_env *env, struct cl_lock *lock)
808 struct cl_object_header *head;
809 const struct cl_lock_slice *slice;
811 LINVRNT(cl_lock_is_mutexed(lock));
812 LINVRNT(cl_lock_invariant(env, lock));
815 if (lock->cll_state < CLS_FREEING) {
816 LASSERT(lock->cll_state != CLS_INTRANSIT);
817 cl_lock_state_set(env, lock, CLS_FREEING);
819 head = cl_object_header(lock->cll_descr.cld_obj);
821 cfs_spin_lock(&head->coh_lock_guard);
822 cfs_list_del_init(&lock->cll_linkage);
824 cfs_spin_unlock(&head->coh_lock_guard);
826 * From now on, no new references to this lock can be acquired
827 * by cl_lock_lookup().
829 cfs_list_for_each_entry_reverse(slice, &lock->cll_layers,
831 if (slice->cls_ops->clo_delete != NULL)
832 slice->cls_ops->clo_delete(env, slice);
835 * From now on, no new references to this lock can be acquired
836 * by layer-specific means (like a pointer from struct
837 * ldlm_lock in osc, or a pointer from top-lock to sub-lock in
840 * Lock will be finally freed in cl_lock_put() when last of
841 * existing references goes away.
848 * Mod(ifie)s cl_lock::cll_holds counter for a given lock. Also, for a
849 * top-lock (nesting == 0) accounts for this modification in the per-thread
850 * debugging counters. Sub-lock holds can be released by a thread different
851 * from one that acquired it.
853 static void cl_lock_hold_mod(const struct lu_env *env, struct cl_lock *lock,
856 struct cl_thread_counters *counters;
857 enum clt_nesting_level nesting;
859 lock->cll_holds += delta;
860 nesting = cl_lock_nesting(lock);
861 if (nesting == CNL_TOP) {
862 counters = &cl_env_info(env)->clt_counters[CNL_TOP];
863 counters->ctc_nr_held += delta;
864 LASSERT(counters->ctc_nr_held >= 0);
869 * Mod(ifie)s cl_lock::cll_users counter for a given lock. See
870 * cl_lock_hold_mod() for the explanation of the debugging code.
872 static void cl_lock_used_mod(const struct lu_env *env, struct cl_lock *lock,
875 struct cl_thread_counters *counters;
876 enum clt_nesting_level nesting;
878 lock->cll_users += delta;
879 nesting = cl_lock_nesting(lock);
880 if (nesting == CNL_TOP) {
881 counters = &cl_env_info(env)->clt_counters[CNL_TOP];
882 counters->ctc_nr_used += delta;
883 LASSERT(counters->ctc_nr_used >= 0);
887 static void cl_lock_hold_release(const struct lu_env *env, struct cl_lock *lock,
888 const char *scope, const void *source)
890 LINVRNT(cl_lock_is_mutexed(lock));
891 LINVRNT(cl_lock_invariant(env, lock));
892 LASSERT(lock->cll_holds > 0);
895 cl_lock_trace(D_DLMTRACE, env, "hold release lock", lock);
896 lu_ref_del(&lock->cll_holders, scope, source);
897 cl_lock_hold_mod(env, lock, -1);
898 if (lock->cll_holds == 0) {
899 CL_LOCK_ASSERT(lock->cll_state != CLS_HELD, env, lock);
900 if (lock->cll_descr.cld_mode == CLM_PHANTOM ||
901 lock->cll_descr.cld_mode == CLM_GROUP ||
902 lock->cll_state != CLS_CACHED)
904 * If lock is still phantom or grouplock when user is
905 * done with it---destroy the lock.
907 lock->cll_flags |= CLF_CANCELPEND|CLF_DOOMED;
908 if (lock->cll_flags & CLF_CANCELPEND) {
909 lock->cll_flags &= ~CLF_CANCELPEND;
910 cl_lock_cancel0(env, lock);
912 if (lock->cll_flags & CLF_DOOMED) {
913 /* no longer doomed: it's dead... Jim. */
914 lock->cll_flags &= ~CLF_DOOMED;
915 cl_lock_delete0(env, lock);
922 * Waits until lock state is changed.
924 * This function is called with cl_lock mutex locked, atomically releases
925 * mutex and goes to sleep, waiting for a lock state change (signaled by
926 * cl_lock_signal()), and re-acquires the mutex before return.
928 * This function is used to wait until lock state machine makes some progress
929 * and to emulate synchronous operations on top of asynchronous lock
932 * \retval -EINTR wait was interrupted
934 * \retval 0 wait wasn't interrupted
936 * \pre cl_lock_is_mutexed(lock)
938 * \see cl_lock_signal()
940 int cl_lock_state_wait(const struct lu_env *env, struct cl_lock *lock)
942 cfs_waitlink_t waiter;
943 cfs_sigset_t blocked;
947 LINVRNT(cl_lock_is_mutexed(lock));
948 LINVRNT(cl_lock_invariant(env, lock));
949 LASSERT(lock->cll_depth == 1);
950 LASSERT(lock->cll_state != CLS_FREEING); /* too late to wait */
952 cl_lock_trace(D_DLMTRACE, env, "state wait lock", lock);
953 result = lock->cll_error;
955 /* To avoid being interrupted by the 'non-fatal' signals
956 * (SIGCHLD, for instance), we'd block them temporarily.
958 blocked = cfs_block_sigsinv(LUSTRE_FATAL_SIGS);
960 cfs_waitlink_init(&waiter);
961 cfs_waitq_add(&lock->cll_wq, &waiter);
962 cfs_set_current_state(CFS_TASK_INTERRUPTIBLE);
963 cl_lock_mutex_put(env, lock);
965 LASSERT(cl_lock_nr_mutexed(env) == 0);
968 if (likely(!OBD_FAIL_CHECK(OBD_FAIL_LOCK_STATE_WAIT_INTR))) {
969 cfs_waitq_wait(&waiter, CFS_TASK_INTERRUPTIBLE);
970 if (!cfs_signal_pending())
974 cl_lock_mutex_get(env, lock);
975 cfs_set_current_state(CFS_TASK_RUNNING);
976 cfs_waitq_del(&lock->cll_wq, &waiter);
978 /* Restore old blocked signals */
979 cfs_restore_sigs(blocked);
983 EXPORT_SYMBOL(cl_lock_state_wait);
985 static void cl_lock_state_signal(const struct lu_env *env, struct cl_lock *lock,
986 enum cl_lock_state state)
988 const struct cl_lock_slice *slice;
991 LINVRNT(cl_lock_is_mutexed(lock));
992 LINVRNT(cl_lock_invariant(env, lock));
994 cfs_list_for_each_entry(slice, &lock->cll_layers, cls_linkage)
995 if (slice->cls_ops->clo_state != NULL)
996 slice->cls_ops->clo_state(env, slice, state);
997 cfs_waitq_broadcast(&lock->cll_wq);
1002 * Notifies waiters that lock state changed.
1004 * Wakes up all waiters sleeping in cl_lock_state_wait(), also notifies all
1005 * layers about state change by calling cl_lock_operations::clo_state()
1008 void cl_lock_signal(const struct lu_env *env, struct cl_lock *lock)
1011 cl_lock_trace(D_DLMTRACE, env, "state signal lock", lock);
1012 cl_lock_state_signal(env, lock, lock->cll_state);
1015 EXPORT_SYMBOL(cl_lock_signal);
1018 * Changes lock state.
1020 * This function is invoked to notify layers that lock state changed, possible
1021 * as a result of an asynchronous event such as call-back reception.
1023 * \post lock->cll_state == state
1025 * \see cl_lock_operations::clo_state()
1027 void cl_lock_state_set(const struct lu_env *env, struct cl_lock *lock,
1028 enum cl_lock_state state)
1030 struct cl_site *site = cl_object_site(lock->cll_descr.cld_obj);
1033 LASSERT(lock->cll_state <= state ||
1034 (lock->cll_state == CLS_CACHED &&
1035 (state == CLS_HELD || /* lock found in cache */
1036 state == CLS_NEW || /* sub-lock canceled */
1037 state == CLS_INTRANSIT)) ||
1038 /* lock is in transit state */
1039 lock->cll_state == CLS_INTRANSIT);
1041 if (lock->cll_state != state) {
1042 cfs_atomic_dec(&site->cs_locks_state[lock->cll_state]);
1043 cfs_atomic_inc(&site->cs_locks_state[state]);
1045 cl_lock_state_signal(env, lock, state);
1046 lock->cll_state = state;
1050 EXPORT_SYMBOL(cl_lock_state_set);
1052 static int cl_unuse_try_internal(const struct lu_env *env, struct cl_lock *lock)
1054 const struct cl_lock_slice *slice;
1060 LINVRNT(cl_lock_is_mutexed(lock));
1061 LINVRNT(cl_lock_invariant(env, lock));
1062 LASSERT(lock->cll_state == CLS_INTRANSIT);
1065 cfs_list_for_each_entry_reverse(slice, &lock->cll_layers,
1067 if (slice->cls_ops->clo_unuse != NULL) {
1068 result = slice->cls_ops->clo_unuse(env, slice);
1073 LASSERT(result != -ENOSYS);
1074 } while (result == CLO_REPEAT);
1080 * Yanks lock from the cache (cl_lock_state::CLS_CACHED state) by calling
1081 * cl_lock_operations::clo_use() top-to-bottom to notify layers.
1082 * @atomic = 1, it must unuse the lock to recovery the lock to keep the
1083 * use process atomic
1085 int cl_use_try(const struct lu_env *env, struct cl_lock *lock, int atomic)
1087 const struct cl_lock_slice *slice;
1089 enum cl_lock_state state;
1092 cl_lock_trace(D_DLMTRACE, env, "use lock", lock);
1094 LASSERT(lock->cll_state == CLS_CACHED);
1095 if (lock->cll_error)
1096 RETURN(lock->cll_error);
1099 state = cl_lock_intransit(env, lock);
1100 cfs_list_for_each_entry(slice, &lock->cll_layers, cls_linkage) {
1101 if (slice->cls_ops->clo_use != NULL) {
1102 result = slice->cls_ops->clo_use(env, slice);
1107 LASSERT(result != -ENOSYS);
1109 LASSERTF(lock->cll_state == CLS_INTRANSIT, "Wrong state %d.\n",
1115 if (result == -ESTALE) {
1117 * ESTALE means sublock being cancelled
1118 * at this time, and set lock state to
1119 * be NEW here and ask the caller to repeat.
1122 result = CLO_REPEAT;
1125 /* @atomic means back-off-on-failure. */
1128 rc = cl_unuse_try_internal(env, lock);
1129 /* Vet the results. */
1130 if (rc < 0 && result > 0)
1135 cl_lock_extransit(env, lock, state);
1138 EXPORT_SYMBOL(cl_use_try);
1141 * Helper for cl_enqueue_try() that calls ->clo_enqueue() across all layers
1144 static int cl_enqueue_kick(const struct lu_env *env,
1145 struct cl_lock *lock,
1146 struct cl_io *io, __u32 flags)
1149 const struct cl_lock_slice *slice;
1153 cfs_list_for_each_entry(slice, &lock->cll_layers, cls_linkage) {
1154 if (slice->cls_ops->clo_enqueue != NULL) {
1155 result = slice->cls_ops->clo_enqueue(env,
1161 LASSERT(result != -ENOSYS);
1166 * Tries to enqueue a lock.
1168 * This function is called repeatedly by cl_enqueue() until either lock is
1169 * enqueued, or error occurs. This function does not block waiting for
1170 * networking communication to complete.
1172 * \post ergo(result == 0, lock->cll_state == CLS_ENQUEUED ||
1173 * lock->cll_state == CLS_HELD)
1175 * \see cl_enqueue() cl_lock_operations::clo_enqueue()
1176 * \see cl_lock_state::CLS_ENQUEUED
1178 int cl_enqueue_try(const struct lu_env *env, struct cl_lock *lock,
1179 struct cl_io *io, __u32 flags)
1184 cl_lock_trace(D_DLMTRACE, env, "enqueue lock", lock);
1186 LINVRNT(cl_lock_is_mutexed(lock));
1188 result = lock->cll_error;
1192 switch (lock->cll_state) {
1194 cl_lock_state_set(env, lock, CLS_QUEUING);
1198 result = cl_enqueue_kick(env, lock, io, flags);
1200 cl_lock_state_set(env, lock, CLS_ENQUEUED);
1203 LASSERT(cl_lock_is_intransit(lock));
1207 /* yank lock from the cache. */
1208 result = cl_use_try(env, lock, 0);
1217 * impossible, only held locks with increased
1218 * ->cll_holds can be enqueued, and they cannot be
1223 } while (result == CLO_REPEAT);
1226 EXPORT_SYMBOL(cl_enqueue_try);
1229 * Cancel the conflicting lock found during previous enqueue.
1231 * \retval 0 conflicting lock has been canceled.
1232 * \retval -ve error code.
1234 int cl_lock_enqueue_wait(const struct lu_env *env,
1235 struct cl_lock *lock,
1238 struct cl_lock *conflict;
1242 LASSERT(cl_lock_is_mutexed(lock));
1243 LASSERT(lock->cll_state == CLS_QUEUING);
1244 LASSERT(lock->cll_conflict != NULL);
1246 conflict = lock->cll_conflict;
1247 lock->cll_conflict = NULL;
1249 cl_lock_mutex_put(env, lock);
1250 LASSERT(cl_lock_nr_mutexed(env) == 0);
1252 cl_lock_mutex_get(env, conflict);
1253 cl_lock_trace(D_DLMTRACE, env, "enqueue wait", conflict);
1254 cl_lock_cancel(env, conflict);
1255 cl_lock_delete(env, conflict);
1257 while (conflict->cll_state != CLS_FREEING) {
1258 rc = cl_lock_state_wait(env, conflict);
1262 cl_lock_mutex_put(env, conflict);
1263 lu_ref_del(&conflict->cll_reference, "cancel-wait", lock);
1264 cl_lock_put(env, conflict);
1267 cl_lock_mutex_get(env, lock);
1272 EXPORT_SYMBOL(cl_lock_enqueue_wait);
1274 static int cl_enqueue_locked(const struct lu_env *env, struct cl_lock *lock,
1275 struct cl_io *io, __u32 enqflags)
1281 LINVRNT(cl_lock_is_mutexed(lock));
1282 LINVRNT(cl_lock_invariant(env, lock));
1283 LASSERT(lock->cll_holds > 0);
1285 cl_lock_user_add(env, lock);
1287 result = cl_enqueue_try(env, lock, io, enqflags);
1288 if (result == CLO_WAIT) {
1289 if (lock->cll_conflict != NULL)
1290 result = cl_lock_enqueue_wait(env, lock, 1);
1292 result = cl_lock_state_wait(env, lock);
1299 cl_unuse_try(env, lock);
1300 LASSERT(ergo(result == 0 && !(enqflags & CEF_AGL),
1301 lock->cll_state == CLS_ENQUEUED ||
1302 lock->cll_state == CLS_HELD));
1309 * \pre current thread or io owns a hold on lock.
1311 * \post ergo(result == 0, lock->users increased)
1312 * \post ergo(result == 0, lock->cll_state == CLS_ENQUEUED ||
1313 * lock->cll_state == CLS_HELD)
1315 int cl_enqueue(const struct lu_env *env, struct cl_lock *lock,
1316 struct cl_io *io, __u32 enqflags)
1322 cl_lock_lockdep_acquire(env, lock, enqflags);
1323 cl_lock_mutex_get(env, lock);
1324 result = cl_enqueue_locked(env, lock, io, enqflags);
1325 cl_lock_mutex_put(env, lock);
1327 cl_lock_lockdep_release(env, lock);
1328 LASSERT(ergo(result == 0, lock->cll_state == CLS_ENQUEUED ||
1329 lock->cll_state == CLS_HELD));
1332 EXPORT_SYMBOL(cl_enqueue);
1335 * Tries to unlock a lock.
1337 * This function is called to release underlying resource:
1338 * 1. for top lock, the resource is sublocks it held;
1339 * 2. for sublock, the resource is the reference to dlmlock.
1341 * cl_unuse_try is a one-shot operation, so it must NOT return CLO_WAIT.
1343 * \see cl_unuse() cl_lock_operations::clo_unuse()
1344 * \see cl_lock_state::CLS_CACHED
1346 int cl_unuse_try(const struct lu_env *env, struct cl_lock *lock)
1349 enum cl_lock_state state = CLS_NEW;
1352 cl_lock_trace(D_DLMTRACE, env, "unuse lock", lock);
1354 if (lock->cll_users > 1) {
1355 cl_lock_user_del(env, lock);
1359 /* Only if the lock is in CLS_HELD or CLS_ENQUEUED state, it can hold
1360 * underlying resources. */
1361 if (!(lock->cll_state == CLS_HELD || lock->cll_state == CLS_ENQUEUED)) {
1362 cl_lock_user_del(env, lock);
1367 * New lock users (->cll_users) are not protecting unlocking
1368 * from proceeding. From this point, lock eventually reaches
1369 * CLS_CACHED, is reinitialized to CLS_NEW or fails into
1372 state = cl_lock_intransit(env, lock);
1374 result = cl_unuse_try_internal(env, lock);
1375 LASSERT(lock->cll_state == CLS_INTRANSIT);
1376 LASSERT(result != CLO_WAIT);
1377 cl_lock_user_del(env, lock);
1378 if (result == 0 || result == -ESTALE) {
1380 * Return lock back to the cache. This is the only
1381 * place where lock is moved into CLS_CACHED state.
1383 * If one of ->clo_unuse() methods returned -ESTALE, lock
1384 * cannot be placed into cache and has to be
1385 * re-initialized. This happens e.g., when a sub-lock was
1386 * canceled while unlocking was in progress.
1388 if (state == CLS_HELD && result == 0)
1392 cl_lock_extransit(env, lock, state);
1395 * Hide -ESTALE error.
1396 * If the lock is a glimpse lock, and it has multiple
1397 * stripes. Assuming that one of its sublock returned -ENAVAIL,
1398 * and other sublocks are matched write locks. In this case,
1399 * we can't set this lock to error because otherwise some of
1400 * its sublocks may not be canceled. This causes some dirty
1401 * pages won't be written to OSTs. -jay
1405 CERROR("result = %d, this is unlikely!\n", result);
1407 cl_lock_extransit(env, lock, state);
1409 RETURN(result ?: lock->cll_error);
1411 EXPORT_SYMBOL(cl_unuse_try);
1413 static void cl_unuse_locked(const struct lu_env *env, struct cl_lock *lock)
1418 result = cl_unuse_try(env, lock);
1420 CL_LOCK_DEBUG(D_ERROR, env, lock, "unuse return %d\n", result);
1428 void cl_unuse(const struct lu_env *env, struct cl_lock *lock)
1431 cl_lock_mutex_get(env, lock);
1432 cl_unuse_locked(env, lock);
1433 cl_lock_mutex_put(env, lock);
1434 cl_lock_lockdep_release(env, lock);
1437 EXPORT_SYMBOL(cl_unuse);
1440 * Tries to wait for a lock.
1442 * This function is called repeatedly by cl_wait() until either lock is
1443 * granted, or error occurs. This function does not block waiting for network
1444 * communication to complete.
1446 * \see cl_wait() cl_lock_operations::clo_wait()
1447 * \see cl_lock_state::CLS_HELD
1449 int cl_wait_try(const struct lu_env *env, struct cl_lock *lock)
1451 const struct cl_lock_slice *slice;
1455 cl_lock_trace(D_DLMTRACE, env, "wait lock try", lock);
1457 LINVRNT(cl_lock_is_mutexed(lock));
1458 LINVRNT(cl_lock_invariant(env, lock));
1459 LASSERT(lock->cll_state == CLS_ENQUEUED ||
1460 lock->cll_state == CLS_HELD ||
1461 lock->cll_state == CLS_INTRANSIT);
1462 LASSERT(lock->cll_users > 0);
1463 LASSERT(lock->cll_holds > 0);
1465 result = lock->cll_error;
1469 if (cl_lock_is_intransit(lock)) {
1474 if (lock->cll_state == CLS_HELD)
1479 cfs_list_for_each_entry(slice, &lock->cll_layers, cls_linkage) {
1480 if (slice->cls_ops->clo_wait != NULL) {
1481 result = slice->cls_ops->clo_wait(env, slice);
1486 LASSERT(result != -ENOSYS);
1488 LASSERT(lock->cll_state != CLS_INTRANSIT);
1489 cl_lock_state_set(env, lock, CLS_HELD);
1491 } while (result == CLO_REPEAT);
1494 EXPORT_SYMBOL(cl_wait_try);
1497 * Waits until enqueued lock is granted.
1499 * \pre current thread or io owns a hold on the lock
1500 * \pre ergo(result == 0, lock->cll_state == CLS_ENQUEUED ||
1501 * lock->cll_state == CLS_HELD)
1503 * \post ergo(result == 0, lock->cll_state == CLS_HELD)
1505 int cl_wait(const struct lu_env *env, struct cl_lock *lock)
1510 cl_lock_mutex_get(env, lock);
1512 LINVRNT(cl_lock_invariant(env, lock));
1513 LASSERTF(lock->cll_state == CLS_ENQUEUED || lock->cll_state == CLS_HELD,
1514 "Wrong state %d \n", lock->cll_state);
1515 LASSERT(lock->cll_holds > 0);
1518 result = cl_wait_try(env, lock);
1519 if (result == CLO_WAIT) {
1520 result = cl_lock_state_wait(env, lock);
1527 cl_unuse_try(env, lock);
1528 cl_lock_lockdep_release(env, lock);
1530 cl_lock_trace(D_DLMTRACE, env, "wait lock", lock);
1531 cl_lock_mutex_put(env, lock);
1532 LASSERT(ergo(result == 0, lock->cll_state == CLS_HELD));
1535 EXPORT_SYMBOL(cl_wait);
1538 * Executes cl_lock_operations::clo_weigh(), and sums results to estimate lock
1541 unsigned long cl_lock_weigh(const struct lu_env *env, struct cl_lock *lock)
1543 const struct cl_lock_slice *slice;
1544 unsigned long pound;
1545 unsigned long ounce;
1548 LINVRNT(cl_lock_is_mutexed(lock));
1549 LINVRNT(cl_lock_invariant(env, lock));
1552 cfs_list_for_each_entry_reverse(slice, &lock->cll_layers, cls_linkage) {
1553 if (slice->cls_ops->clo_weigh != NULL) {
1554 ounce = slice->cls_ops->clo_weigh(env, slice);
1556 if (pound < ounce) /* over-weight^Wflow */
1562 EXPORT_SYMBOL(cl_lock_weigh);
1565 * Notifies layers that lock description changed.
1567 * The server can grant client a lock different from one that was requested
1568 * (e.g., larger in extent). This method is called when actually granted lock
1569 * description becomes known to let layers to accommodate for changed lock
1572 * \see cl_lock_operations::clo_modify()
1574 int cl_lock_modify(const struct lu_env *env, struct cl_lock *lock,
1575 const struct cl_lock_descr *desc)
1577 const struct cl_lock_slice *slice;
1578 struct cl_object *obj = lock->cll_descr.cld_obj;
1579 struct cl_object_header *hdr = cl_object_header(obj);
1583 cl_lock_trace(D_DLMTRACE, env, "modify lock", lock);
1584 /* don't allow object to change */
1585 LASSERT(obj == desc->cld_obj);
1586 LINVRNT(cl_lock_is_mutexed(lock));
1587 LINVRNT(cl_lock_invariant(env, lock));
1589 cfs_list_for_each_entry_reverse(slice, &lock->cll_layers, cls_linkage) {
1590 if (slice->cls_ops->clo_modify != NULL) {
1591 result = slice->cls_ops->clo_modify(env, slice, desc);
1596 CL_LOCK_DEBUG(D_DLMTRACE, env, lock, " -> "DDESCR"@"DFID"\n",
1597 PDESCR(desc), PFID(lu_object_fid(&desc->cld_obj->co_lu)));
1599 * Just replace description in place. Nothing more is needed for
1600 * now. If locks were indexed according to their extent and/or mode,
1601 * that index would have to be updated here.
1603 cfs_spin_lock(&hdr->coh_lock_guard);
1604 lock->cll_descr = *desc;
1605 cfs_spin_unlock(&hdr->coh_lock_guard);
1608 EXPORT_SYMBOL(cl_lock_modify);
1611 * Initializes lock closure with a given origin.
1613 * \see cl_lock_closure
1615 void cl_lock_closure_init(const struct lu_env *env,
1616 struct cl_lock_closure *closure,
1617 struct cl_lock *origin, int wait)
1619 LINVRNT(cl_lock_is_mutexed(origin));
1620 LINVRNT(cl_lock_invariant(env, origin));
1622 CFS_INIT_LIST_HEAD(&closure->clc_list);
1623 closure->clc_origin = origin;
1624 closure->clc_wait = wait;
1625 closure->clc_nr = 0;
1627 EXPORT_SYMBOL(cl_lock_closure_init);
1630 * Builds a closure of \a lock.
1632 * Building of a closure consists of adding initial lock (\a lock) into it,
1633 * and calling cl_lock_operations::clo_closure() methods of \a lock. These
1634 * methods might call cl_lock_closure_build() recursively again, adding more
1635 * locks to the closure, etc.
1637 * \see cl_lock_closure
1639 int cl_lock_closure_build(const struct lu_env *env, struct cl_lock *lock,
1640 struct cl_lock_closure *closure)
1642 const struct cl_lock_slice *slice;
1646 LINVRNT(cl_lock_is_mutexed(closure->clc_origin));
1647 LINVRNT(cl_lock_invariant(env, closure->clc_origin));
1649 result = cl_lock_enclosure(env, lock, closure);
1651 cfs_list_for_each_entry(slice, &lock->cll_layers, cls_linkage) {
1652 if (slice->cls_ops->clo_closure != NULL) {
1653 result = slice->cls_ops->clo_closure(env, slice,
1661 cl_lock_disclosure(env, closure);
1664 EXPORT_SYMBOL(cl_lock_closure_build);
1667 * Adds new lock to a closure.
1669 * Try-locks \a lock and if succeeded, adds it to the closure (never more than
1670 * once). If try-lock failed, returns CLO_REPEAT, after optionally waiting
1671 * until next try-lock is likely to succeed.
1673 int cl_lock_enclosure(const struct lu_env *env, struct cl_lock *lock,
1674 struct cl_lock_closure *closure)
1678 cl_lock_trace(D_DLMTRACE, env, "enclosure lock", lock);
1679 if (!cl_lock_mutex_try(env, lock)) {
1681 * If lock->cll_inclosure is not empty, lock is already in
1684 if (cfs_list_empty(&lock->cll_inclosure)) {
1685 cl_lock_get_trust(lock);
1686 lu_ref_add(&lock->cll_reference, "closure", closure);
1687 cfs_list_add(&lock->cll_inclosure, &closure->clc_list);
1690 cl_lock_mutex_put(env, lock);
1693 cl_lock_disclosure(env, closure);
1694 if (closure->clc_wait) {
1695 cl_lock_get_trust(lock);
1696 lu_ref_add(&lock->cll_reference, "closure-w", closure);
1697 cl_lock_mutex_put(env, closure->clc_origin);
1699 LASSERT(cl_lock_nr_mutexed(env) == 0);
1700 cl_lock_mutex_get(env, lock);
1701 cl_lock_mutex_put(env, lock);
1703 cl_lock_mutex_get(env, closure->clc_origin);
1704 lu_ref_del(&lock->cll_reference, "closure-w", closure);
1705 cl_lock_put(env, lock);
1707 result = CLO_REPEAT;
1711 EXPORT_SYMBOL(cl_lock_enclosure);
1713 /** Releases mutices of enclosed locks. */
1714 void cl_lock_disclosure(const struct lu_env *env,
1715 struct cl_lock_closure *closure)
1717 struct cl_lock *scan;
1718 struct cl_lock *temp;
1720 cl_lock_trace(D_DLMTRACE, env, "disclosure lock", closure->clc_origin);
1721 cfs_list_for_each_entry_safe(scan, temp, &closure->clc_list,
1723 cfs_list_del_init(&scan->cll_inclosure);
1724 cl_lock_mutex_put(env, scan);
1725 lu_ref_del(&scan->cll_reference, "closure", closure);
1726 cl_lock_put(env, scan);
1729 LASSERT(closure->clc_nr == 0);
1731 EXPORT_SYMBOL(cl_lock_disclosure);
1733 /** Finalizes a closure. */
1734 void cl_lock_closure_fini(struct cl_lock_closure *closure)
1736 LASSERT(closure->clc_nr == 0);
1737 LASSERT(cfs_list_empty(&closure->clc_list));
1739 EXPORT_SYMBOL(cl_lock_closure_fini);
1742 * Destroys this lock. Notifies layers (bottom-to-top) that lock is being
1743 * destroyed, then destroy the lock. If there are holds on the lock, postpone
1744 * destruction until all holds are released. This is called when a decision is
1745 * made to destroy the lock in the future. E.g., when a blocking AST is
1746 * received on it, or fatal communication error happens.
1748 * Caller must have a reference on this lock to prevent a situation, when
1749 * deleted lock lingers in memory for indefinite time, because nobody calls
1750 * cl_lock_put() to finish it.
1752 * \pre atomic_read(&lock->cll_ref) > 0
1753 * \pre ergo(cl_lock_nesting(lock) == CNL_TOP,
1754 * cl_lock_nr_mutexed(env) == 1)
1755 * [i.e., if a top-lock is deleted, mutices of no other locks can be
1756 * held, as deletion of sub-locks might require releasing a top-lock
1759 * \see cl_lock_operations::clo_delete()
1760 * \see cl_lock::cll_holds
1762 void cl_lock_delete(const struct lu_env *env, struct cl_lock *lock)
1764 LINVRNT(cl_lock_is_mutexed(lock));
1765 LINVRNT(cl_lock_invariant(env, lock));
1766 LASSERT(ergo(cl_lock_nesting(lock) == CNL_TOP,
1767 cl_lock_nr_mutexed(env) == 1));
1770 cl_lock_trace(D_DLMTRACE, env, "delete lock", lock);
1771 if (lock->cll_holds == 0)
1772 cl_lock_delete0(env, lock);
1774 lock->cll_flags |= CLF_DOOMED;
1777 EXPORT_SYMBOL(cl_lock_delete);
1780 * Mark lock as irrecoverably failed, and mark it for destruction. This
1781 * happens when, e.g., server fails to grant a lock to us, or networking
1784 * \pre atomic_read(&lock->cll_ref) > 0
1786 * \see clo_lock_delete()
1787 * \see cl_lock::cll_holds
1789 void cl_lock_error(const struct lu_env *env, struct cl_lock *lock, int error)
1791 LINVRNT(cl_lock_is_mutexed(lock));
1792 LINVRNT(cl_lock_invariant(env, lock));
1795 if (lock->cll_error == 0 && error != 0) {
1796 cl_lock_trace(D_DLMTRACE, env, "set lock error", lock);
1797 lock->cll_error = error;
1798 cl_lock_signal(env, lock);
1799 cl_lock_cancel(env, lock);
1800 cl_lock_delete(env, lock);
1804 EXPORT_SYMBOL(cl_lock_error);
1807 * Cancels this lock. Notifies layers
1808 * (bottom-to-top) that lock is being cancelled, then destroy the lock. If
1809 * there are holds on the lock, postpone cancellation until
1810 * all holds are released.
1812 * Cancellation notification is delivered to layers at most once.
1814 * \see cl_lock_operations::clo_cancel()
1815 * \see cl_lock::cll_holds
1817 void cl_lock_cancel(const struct lu_env *env, struct cl_lock *lock)
1819 LINVRNT(cl_lock_is_mutexed(lock));
1820 LINVRNT(cl_lock_invariant(env, lock));
1823 cl_lock_trace(D_DLMTRACE, env, "cancel lock", lock);
1824 if (lock->cll_holds == 0)
1825 cl_lock_cancel0(env, lock);
1827 lock->cll_flags |= CLF_CANCELPEND;
1830 EXPORT_SYMBOL(cl_lock_cancel);
1833 * Finds an existing lock covering given index and optionally different from a
1834 * given \a except lock.
1836 struct cl_lock *cl_lock_at_pgoff(const struct lu_env *env,
1837 struct cl_object *obj, pgoff_t index,
1838 struct cl_lock *except,
1839 int pending, int canceld)
1841 struct cl_object_header *head;
1842 struct cl_lock *scan;
1843 struct cl_lock *lock;
1844 struct cl_lock_descr *need;
1848 head = cl_object_header(obj);
1849 need = &cl_env_info(env)->clt_descr;
1852 need->cld_mode = CLM_READ; /* CLM_READ matches both READ & WRITE, but
1854 need->cld_start = need->cld_end = index;
1855 need->cld_enq_flags = 0;
1857 cfs_spin_lock(&head->coh_lock_guard);
1858 /* It is fine to match any group lock since there could be only one
1859 * with a uniq gid and it conflicts with all other lock modes too */
1860 cfs_list_for_each_entry(scan, &head->coh_locks, cll_linkage) {
1861 if (scan != except &&
1862 (scan->cll_descr.cld_mode == CLM_GROUP ||
1863 cl_lock_ext_match(&scan->cll_descr, need)) &&
1864 scan->cll_state >= CLS_HELD &&
1865 scan->cll_state < CLS_FREEING &&
1867 * This check is racy as the lock can be canceled right
1868 * after it is done, but this is fine, because page exists
1871 (canceld || !(scan->cll_flags & CLF_CANCELLED)) &&
1872 (pending || !(scan->cll_flags & CLF_CANCELPEND))) {
1873 /* Don't increase cs_hit here since this
1874 * is just a helper function. */
1875 cl_lock_get_trust(scan);
1880 cfs_spin_unlock(&head->coh_lock_guard);
1883 EXPORT_SYMBOL(cl_lock_at_pgoff);
1886 * Calculate the page offset at the layer of @lock.
1887 * At the time of this writing, @page is top page and @lock is sub lock.
1889 static pgoff_t pgoff_at_lock(struct cl_page *page, struct cl_lock *lock)
1891 struct lu_device_type *dtype;
1892 const struct cl_page_slice *slice;
1894 dtype = lock->cll_descr.cld_obj->co_lu.lo_dev->ld_type;
1895 slice = cl_page_at(page, dtype);
1896 LASSERT(slice != NULL);
1897 return slice->cpl_page->cp_index;
1901 * Check if page @page is covered by an extra lock or discard it.
1903 static int check_and_discard_cb(const struct lu_env *env, struct cl_io *io,
1904 struct cl_page *page, void *cbdata)
1906 struct cl_thread_info *info = cl_env_info(env);
1907 struct cl_lock *lock = cbdata;
1908 pgoff_t index = pgoff_at_lock(page, lock);
1910 if (index >= info->clt_fn_index) {
1911 struct cl_lock *tmp;
1913 /* refresh non-overlapped index */
1914 tmp = cl_lock_at_page(env, lock->cll_descr.cld_obj, page, lock,
1917 /* Cache the first-non-overlapped index so as to skip
1918 * all pages within [index, clt_fn_index). This
1919 * is safe because if tmp lock is canceled, it will
1920 * discard these pages. */
1921 info->clt_fn_index = tmp->cll_descr.cld_end + 1;
1922 if (tmp->cll_descr.cld_end == CL_PAGE_EOF)
1923 info->clt_fn_index = CL_PAGE_EOF;
1924 cl_lock_put(env, tmp);
1925 } else if (cl_page_own(env, io, page) == 0) {
1926 /* discard the page */
1927 cl_page_unmap(env, io, page);
1928 cl_page_discard(env, io, page);
1929 cl_page_disown(env, io, page);
1931 LASSERT(page->cp_state == CPS_FREEING);
1935 info->clt_next_index = index + 1;
1936 return CLP_GANG_OKAY;
1939 static int discard_cb(const struct lu_env *env, struct cl_io *io,
1940 struct cl_page *page, void *cbdata)
1942 struct cl_thread_info *info = cl_env_info(env);
1943 struct cl_lock *lock = cbdata;
1945 LASSERT(lock->cll_descr.cld_mode >= CLM_WRITE);
1946 KLASSERT(ergo(page->cp_type == CPT_CACHEABLE,
1947 !PageWriteback(cl_page_vmpage(env, page))));
1948 KLASSERT(ergo(page->cp_type == CPT_CACHEABLE,
1949 !PageDirty(cl_page_vmpage(env, page))));
1951 info->clt_next_index = pgoff_at_lock(page, lock) + 1;
1952 if (cl_page_own(env, io, page) == 0) {
1953 /* discard the page */
1954 cl_page_unmap(env, io, page);
1955 cl_page_discard(env, io, page);
1956 cl_page_disown(env, io, page);
1958 LASSERT(page->cp_state == CPS_FREEING);
1961 return CLP_GANG_OKAY;
1965 * Discard pages protected by the given lock. This function traverses radix
1966 * tree to find all covering pages and discard them. If a page is being covered
1967 * by other locks, it should remain in cache.
1969 * If error happens on any step, the process continues anyway (the reasoning
1970 * behind this being that lock cancellation cannot be delayed indefinitely).
1972 int cl_lock_discard_pages(const struct lu_env *env, struct cl_lock *lock)
1974 struct cl_thread_info *info = cl_env_info(env);
1975 struct cl_io *io = &info->clt_io;
1976 struct cl_lock_descr *descr = &lock->cll_descr;
1977 cl_page_gang_cb_t cb;
1981 LINVRNT(cl_lock_invariant(env, lock));
1984 io->ci_obj = cl_object_top(descr->cld_obj);
1985 result = cl_io_init(env, io, CIT_MISC, io->ci_obj);
1989 cb = descr->cld_mode == CLM_READ ? check_and_discard_cb : discard_cb;
1990 info->clt_fn_index = info->clt_next_index = descr->cld_start;
1992 res = cl_page_gang_lookup(env, descr->cld_obj, io,
1993 info->clt_next_index, descr->cld_end,
1995 if (info->clt_next_index > descr->cld_end)
1998 if (res == CLP_GANG_RESCHED)
2000 } while (res != CLP_GANG_OKAY);
2002 cl_io_fini(env, io);
2005 EXPORT_SYMBOL(cl_lock_discard_pages);
2008 * Eliminate all locks for a given object.
2010 * Caller has to guarantee that no lock is in active use.
2012 * \param cancel when this is set, cl_locks_prune() cancels locks before
2015 void cl_locks_prune(const struct lu_env *env, struct cl_object *obj, int cancel)
2017 struct cl_object_header *head;
2018 struct cl_lock *lock;
2021 head = cl_object_header(obj);
2023 * If locks are destroyed without cancellation, all pages must be
2024 * already destroyed (as otherwise they will be left unprotected).
2026 LASSERT(ergo(!cancel,
2027 head->coh_tree.rnode == NULL && head->coh_pages == 0));
2029 cfs_spin_lock(&head->coh_lock_guard);
2030 while (!cfs_list_empty(&head->coh_locks)) {
2031 lock = container_of(head->coh_locks.next,
2032 struct cl_lock, cll_linkage);
2033 cl_lock_get_trust(lock);
2034 cfs_spin_unlock(&head->coh_lock_guard);
2035 lu_ref_add(&lock->cll_reference, "prune", cfs_current());
2038 cl_lock_mutex_get(env, lock);
2039 if (lock->cll_state < CLS_FREEING) {
2040 LASSERT(lock->cll_holds == 0);
2041 LASSERT(lock->cll_users <= 1);
2042 if (unlikely(lock->cll_users == 1)) {
2043 struct l_wait_info lwi = { 0 };
2045 cl_lock_mutex_put(env, lock);
2046 l_wait_event(lock->cll_wq,
2047 lock->cll_users == 0,
2053 cl_lock_cancel(env, lock);
2054 cl_lock_delete(env, lock);
2056 cl_lock_mutex_put(env, lock);
2057 lu_ref_del(&lock->cll_reference, "prune", cfs_current());
2058 cl_lock_put(env, lock);
2059 cfs_spin_lock(&head->coh_lock_guard);
2061 cfs_spin_unlock(&head->coh_lock_guard);
2064 EXPORT_SYMBOL(cl_locks_prune);
2066 static struct cl_lock *cl_lock_hold_mutex(const struct lu_env *env,
2067 const struct cl_io *io,
2068 const struct cl_lock_descr *need,
2069 const char *scope, const void *source)
2071 struct cl_lock *lock;
2076 lock = cl_lock_find(env, io, need);
2079 cl_lock_mutex_get(env, lock);
2080 if (lock->cll_state < CLS_FREEING &&
2081 !(lock->cll_flags & CLF_CANCELLED)) {
2082 cl_lock_hold_mod(env, lock, +1);
2083 lu_ref_add(&lock->cll_holders, scope, source);
2084 lu_ref_add(&lock->cll_reference, scope, source);
2087 cl_lock_mutex_put(env, lock);
2088 cl_lock_put(env, lock);
2094 * Returns a lock matching \a need description with a reference and a hold on
2097 * This is much like cl_lock_find(), except that cl_lock_hold() additionally
2098 * guarantees that lock is not in the CLS_FREEING state on return.
2100 struct cl_lock *cl_lock_hold(const struct lu_env *env, const struct cl_io *io,
2101 const struct cl_lock_descr *need,
2102 const char *scope, const void *source)
2104 struct cl_lock *lock;
2108 lock = cl_lock_hold_mutex(env, io, need, scope, source);
2110 cl_lock_mutex_put(env, lock);
2113 EXPORT_SYMBOL(cl_lock_hold);
2116 * Main high-level entry point of cl_lock interface that finds existing or
2117 * enqueues new lock matching given description.
2119 struct cl_lock *cl_lock_request(const struct lu_env *env, struct cl_io *io,
2120 const struct cl_lock_descr *need,
2121 const char *scope, const void *source)
2123 struct cl_lock *lock;
2125 __u32 enqflags = need->cld_enq_flags;
2129 lock = cl_lock_hold_mutex(env, io, need, scope, source);
2133 rc = cl_enqueue_locked(env, lock, io, enqflags);
2135 if (cl_lock_fits_into(env, lock, need, io)) {
2136 if (!(enqflags & CEF_AGL)) {
2137 cl_lock_mutex_put(env, lock);
2138 cl_lock_lockdep_acquire(env, lock,
2144 cl_unuse_locked(env, lock);
2146 cl_lock_trace(D_DLMTRACE, env,
2147 rc <= 0 ? "enqueue failed" : "agl succeed", lock);
2148 cl_lock_hold_release(env, lock, scope, source);
2149 cl_lock_mutex_put(env, lock);
2150 lu_ref_del(&lock->cll_reference, scope, source);
2151 cl_lock_put(env, lock);
2153 LASSERT(enqflags & CEF_AGL);
2155 } else if (rc != 0) {
2161 EXPORT_SYMBOL(cl_lock_request);
2164 * Adds a hold to a known lock.
2166 void cl_lock_hold_add(const struct lu_env *env, struct cl_lock *lock,
2167 const char *scope, const void *source)
2169 LINVRNT(cl_lock_is_mutexed(lock));
2170 LINVRNT(cl_lock_invariant(env, lock));
2171 LASSERT(lock->cll_state != CLS_FREEING);
2174 cl_lock_hold_mod(env, lock, +1);
2176 lu_ref_add(&lock->cll_holders, scope, source);
2177 lu_ref_add(&lock->cll_reference, scope, source);
2180 EXPORT_SYMBOL(cl_lock_hold_add);
2183 * Releases a hold and a reference on a lock, on which caller acquired a
2186 void cl_lock_unhold(const struct lu_env *env, struct cl_lock *lock,
2187 const char *scope, const void *source)
2189 LINVRNT(cl_lock_invariant(env, lock));
2191 cl_lock_hold_release(env, lock, scope, source);
2192 lu_ref_del(&lock->cll_reference, scope, source);
2193 cl_lock_put(env, lock);
2196 EXPORT_SYMBOL(cl_lock_unhold);
2199 * Releases a hold and a reference on a lock, obtained by cl_lock_hold().
2201 void cl_lock_release(const struct lu_env *env, struct cl_lock *lock,
2202 const char *scope, const void *source)
2204 LINVRNT(cl_lock_invariant(env, lock));
2206 cl_lock_trace(D_DLMTRACE, env, "release lock", lock);
2207 cl_lock_mutex_get(env, lock);
2208 cl_lock_hold_release(env, lock, scope, source);
2209 cl_lock_mutex_put(env, lock);
2210 lu_ref_del(&lock->cll_reference, scope, source);
2211 cl_lock_put(env, lock);
2214 EXPORT_SYMBOL(cl_lock_release);
2216 void cl_lock_user_add(const struct lu_env *env, struct cl_lock *lock)
2218 LINVRNT(cl_lock_is_mutexed(lock));
2219 LINVRNT(cl_lock_invariant(env, lock));
2222 cl_lock_used_mod(env, lock, +1);
2225 EXPORT_SYMBOL(cl_lock_user_add);
2227 void cl_lock_user_del(const struct lu_env *env, struct cl_lock *lock)
2229 LINVRNT(cl_lock_is_mutexed(lock));
2230 LINVRNT(cl_lock_invariant(env, lock));
2231 LASSERT(lock->cll_users > 0);
2234 cl_lock_used_mod(env, lock, -1);
2235 if (lock->cll_users == 0)
2236 cfs_waitq_broadcast(&lock->cll_wq);
2239 EXPORT_SYMBOL(cl_lock_user_del);
2241 const char *cl_lock_mode_name(const enum cl_lock_mode mode)
2243 static const char *names[] = {
2244 [CLM_PHANTOM] = "P",
2249 if (0 <= mode && mode < ARRAY_SIZE(names))
2254 EXPORT_SYMBOL(cl_lock_mode_name);
2257 * Prints human readable representation of a lock description.
2259 void cl_lock_descr_print(const struct lu_env *env, void *cookie,
2260 lu_printer_t printer,
2261 const struct cl_lock_descr *descr)
2263 const struct lu_fid *fid;
2265 fid = lu_object_fid(&descr->cld_obj->co_lu);
2266 (*printer)(env, cookie, DDESCR"@"DFID, PDESCR(descr), PFID(fid));
2268 EXPORT_SYMBOL(cl_lock_descr_print);
2271 * Prints human readable representation of \a lock to the \a f.
2273 void cl_lock_print(const struct lu_env *env, void *cookie,
2274 lu_printer_t printer, const struct cl_lock *lock)
2276 const struct cl_lock_slice *slice;
2277 (*printer)(env, cookie, "lock@%p[%d %d %d %d %d %08lx] ",
2278 lock, cfs_atomic_read(&lock->cll_ref),
2279 lock->cll_state, lock->cll_error, lock->cll_holds,
2280 lock->cll_users, lock->cll_flags);
2281 cl_lock_descr_print(env, cookie, printer, &lock->cll_descr);
2282 (*printer)(env, cookie, " {\n");
2284 cfs_list_for_each_entry(slice, &lock->cll_layers, cls_linkage) {
2285 (*printer)(env, cookie, " %s@%p: ",
2286 slice->cls_obj->co_lu.lo_dev->ld_type->ldt_name,
2288 if (slice->cls_ops->clo_print != NULL)
2289 slice->cls_ops->clo_print(env, cookie, printer, slice);
2290 (*printer)(env, cookie, "\n");
2292 (*printer)(env, cookie, "} lock@%p\n", lock);
2294 EXPORT_SYMBOL(cl_lock_print);
2296 int cl_lock_init(void)
2298 return lu_kmem_init(cl_lock_caches);
2301 void cl_lock_fini(void)
2303 lu_kmem_fini(cl_lock_caches);