4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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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) 2007, 2010, Oracle and/or its affiliates. All rights reserved.
28 * Use is subject to license terms.
30 * Copyright (c) 2011, 2013, Intel Corporation.
33 * This file is part of Lustre, http://www.lustre.org/
34 * Lustre is a trademark of Sun Microsystems, Inc.
36 * lustre/obdclass/lu_object.c
39 * These are the only exported functions, they provide some generic
40 * infrastructure for managing object devices
42 * Author: Nikita Danilov <nikita.danilov@sun.com>
45 #define DEBUG_SUBSYSTEM S_CLASS
47 #include <libcfs/libcfs.h>
50 # include <linux/module.h>
54 #include <libcfs/libcfs_hash.h>
55 #include <obd_class.h>
56 #include <obd_support.h>
57 #include <lustre_disk.h>
58 #include <lustre_fid.h>
59 #include <lu_object.h>
61 #include <libcfs/list.h>
63 extern spinlock_t obd_types_lock;
66 LU_CACHE_PERCENT_MAX = 50,
67 LU_CACHE_PERCENT_DEFAULT = 20
70 #define LU_CACHE_NR_MAX_ADJUST 128
71 #define LU_CACHE_NR_UNLIMITED -1
72 #define LU_CACHE_NR_DEFAULT LU_CACHE_NR_UNLIMITED
73 #define LU_CACHE_NR_LDISKFS_LIMIT LU_CACHE_NR_UNLIMITED
74 #define LU_CACHE_NR_ZFS_LIMIT 256
76 #define LU_SITE_BITS_MIN 12
77 #define LU_SITE_BITS_MAX 24
79 * total 256 buckets, we don't want too many buckets because:
80 * - consume too much memory
81 * - avoid unbalanced LRU list
83 #define LU_SITE_BKT_BITS 8
86 static unsigned int lu_cache_percent = LU_CACHE_PERCENT_DEFAULT;
87 CFS_MODULE_PARM(lu_cache_percent, "i", int, 0644,
88 "Percentage of memory to be used as lu_object cache");
90 static long lu_cache_nr = LU_CACHE_NR_DEFAULT;
91 CFS_MODULE_PARM(lu_cache_nr, "l", long, 0644,
92 "Maximum number of objects in lu_object cache");
94 static void lu_object_free(const struct lu_env *env, struct lu_object *o);
97 * Decrease reference counter on object. If last reference is freed, return
98 * object to the cache, unless lu_object_is_dying(o) holds. In the latter
99 * case, free object immediately.
101 void lu_object_put(const struct lu_env *env, struct lu_object *o)
103 struct lu_site_bkt_data *bkt;
104 struct lu_object_header *top;
105 struct lu_site *site;
106 struct lu_object *orig;
108 const struct lu_fid *fid;
111 site = o->lo_dev->ld_site;
115 * till we have full fids-on-OST implemented anonymous objects
116 * are possible in OSP. such an object isn't listed in the site
117 * so we should not remove it from the site.
119 fid = lu_object_fid(o);
120 if (fid_is_zero(fid)) {
121 LASSERT(top->loh_hash.next == NULL
122 && top->loh_hash.pprev == NULL);
123 LASSERT(cfs_list_empty(&top->loh_lru));
124 if (!atomic_dec_and_test(&top->loh_ref))
126 cfs_list_for_each_entry_reverse(o, &top->loh_layers, lo_linkage) {
127 if (o->lo_ops->loo_object_release != NULL)
128 o->lo_ops->loo_object_release(env, o);
130 lu_object_free(env, orig);
134 cfs_hash_bd_get(site->ls_obj_hash, &top->loh_fid, &bd);
135 bkt = cfs_hash_bd_extra_get(site->ls_obj_hash, &bd);
137 if (!cfs_hash_bd_dec_and_lock(site->ls_obj_hash, &bd, &top->loh_ref)) {
138 if (lu_object_is_dying(top)) {
141 * somebody may be waiting for this, currently only
142 * used for cl_object, see cl_object_put_last().
144 wake_up_all(&bkt->lsb_marche_funebre);
149 LASSERT(bkt->lsb_busy > 0);
152 * When last reference is released, iterate over object
153 * layers, and notify them that object is no longer busy.
155 cfs_list_for_each_entry_reverse(o, &top->loh_layers, lo_linkage) {
156 if (o->lo_ops->loo_object_release != NULL)
157 o->lo_ops->loo_object_release(env, o);
160 if (!lu_object_is_dying(top)) {
161 LASSERT(cfs_list_empty(&top->loh_lru));
162 cfs_list_add_tail(&top->loh_lru, &bkt->lsb_lru);
163 cfs_hash_bd_unlock(site->ls_obj_hash, &bd, 1);
168 * If object is dying (will not be cached), removed it
169 * from hash table and LRU.
171 * This is done with hash table and LRU lists locked. As the only
172 * way to acquire first reference to previously unreferenced
173 * object is through hash-table lookup (lu_object_find()),
174 * or LRU scanning (lu_site_purge()), that are done under hash-table
175 * and LRU lock, no race with concurrent object lookup is possible
176 * and we can safely destroy object below.
178 if (!test_and_set_bit(LU_OBJECT_UNHASHED, &top->loh_flags))
179 cfs_hash_bd_del_locked(site->ls_obj_hash, &bd, &top->loh_hash);
180 cfs_hash_bd_unlock(site->ls_obj_hash, &bd, 1);
182 * Object was already removed from hash and lru above, can
185 lu_object_free(env, orig);
187 EXPORT_SYMBOL(lu_object_put);
190 * Put object and don't keep in cache. This is temporary solution for
191 * multi-site objects when its layering is not constant.
193 void lu_object_put_nocache(const struct lu_env *env, struct lu_object *o)
195 set_bit(LU_OBJECT_HEARD_BANSHEE, &o->lo_header->loh_flags);
196 return lu_object_put(env, o);
198 EXPORT_SYMBOL(lu_object_put_nocache);
201 * Kill the object and take it out of LRU cache.
202 * Currently used by client code for layout change.
204 void lu_object_unhash(const struct lu_env *env, struct lu_object *o)
206 struct lu_object_header *top;
209 set_bit(LU_OBJECT_HEARD_BANSHEE, &top->loh_flags);
210 if (!test_and_set_bit(LU_OBJECT_UNHASHED, &top->loh_flags)) {
211 cfs_hash_t *obj_hash = o->lo_dev->ld_site->ls_obj_hash;
214 cfs_hash_bd_get_and_lock(obj_hash, &top->loh_fid, &bd, 1);
215 cfs_list_del_init(&top->loh_lru);
216 cfs_hash_bd_del_locked(obj_hash, &bd, &top->loh_hash);
217 cfs_hash_bd_unlock(obj_hash, &bd, 1);
220 EXPORT_SYMBOL(lu_object_unhash);
223 * Allocate new object.
225 * This follows object creation protocol, described in the comment within
226 * struct lu_device_operations definition.
228 static struct lu_object *lu_object_alloc(const struct lu_env *env,
229 struct lu_device *dev,
230 const struct lu_fid *f,
231 const struct lu_object_conf *conf)
233 struct lu_object *scan;
234 struct lu_object *top;
236 unsigned int init_mask = 0;
237 unsigned int init_flag;
243 * Create top-level object slice. This will also create
246 top = dev->ld_ops->ldo_object_alloc(env, NULL, dev);
248 RETURN(ERR_PTR(-ENOMEM));
252 * This is the only place where object fid is assigned. It's constant
255 top->lo_header->loh_fid = *f;
256 layers = &top->lo_header->loh_layers;
260 * Call ->loo_object_init() repeatedly, until no more new
261 * object slices are created.
265 cfs_list_for_each_entry(scan, layers, lo_linkage) {
266 if (init_mask & init_flag)
269 scan->lo_header = top->lo_header;
270 result = scan->lo_ops->loo_object_init(env, scan, conf);
272 lu_object_free(env, top);
273 RETURN(ERR_PTR(result));
275 init_mask |= init_flag;
281 cfs_list_for_each_entry_reverse(scan, layers, lo_linkage) {
282 if (scan->lo_ops->loo_object_start != NULL) {
283 result = scan->lo_ops->loo_object_start(env, scan);
285 lu_object_free(env, top);
286 RETURN(ERR_PTR(result));
291 lprocfs_counter_incr(dev->ld_site->ls_stats, LU_SS_CREATED);
298 static void lu_object_free(const struct lu_env *env, struct lu_object *o)
300 struct lu_site_bkt_data *bkt;
301 struct lu_site *site;
302 struct lu_object *scan;
306 site = o->lo_dev->ld_site;
307 layers = &o->lo_header->loh_layers;
308 bkt = lu_site_bkt_from_fid(site, &o->lo_header->loh_fid);
310 * First call ->loo_object_delete() method to release all resources.
312 cfs_list_for_each_entry_reverse(scan, layers, lo_linkage) {
313 if (scan->lo_ops->loo_object_delete != NULL)
314 scan->lo_ops->loo_object_delete(env, scan);
318 * Then, splice object layers into stand-alone list, and call
319 * ->loo_object_free() on all layers to free memory. Splice is
320 * necessary, because lu_object_header is freed together with the
323 CFS_INIT_LIST_HEAD(&splice);
324 cfs_list_splice_init(layers, &splice);
325 while (!cfs_list_empty(&splice)) {
327 * Free layers in bottom-to-top order, so that object header
328 * lives as long as possible and ->loo_object_free() methods
329 * can look at its contents.
331 o = container_of0(splice.prev, struct lu_object, lo_linkage);
332 cfs_list_del_init(&o->lo_linkage);
333 LASSERT(o->lo_ops->loo_object_free != NULL);
334 o->lo_ops->loo_object_free(env, o);
337 if (waitqueue_active(&bkt->lsb_marche_funebre))
338 wake_up_all(&bkt->lsb_marche_funebre);
342 * Free \a nr objects from the cold end of the site LRU list.
344 int lu_site_purge(const struct lu_env *env, struct lu_site *s, int nr)
346 struct lu_object_header *h;
347 struct lu_object_header *temp;
348 struct lu_site_bkt_data *bkt;
358 if (OBD_FAIL_CHECK(OBD_FAIL_OBD_NO_LRU))
361 CFS_INIT_LIST_HEAD(&dispose);
363 * Under LRU list lock, scan LRU list and move unreferenced objects to
364 * the dispose list, removing them from LRU and hash table.
366 start = s->ls_purge_start;
367 bnr = (nr == ~0) ? -1 : nr / CFS_HASH_NBKT(s->ls_obj_hash) + 1;
370 cfs_hash_for_each_bucket(s->ls_obj_hash, &bd, i) {
374 cfs_hash_bd_lock(s->ls_obj_hash, &bd, 1);
375 bkt = cfs_hash_bd_extra_get(s->ls_obj_hash, &bd);
377 cfs_list_for_each_entry_safe(h, temp, &bkt->lsb_lru, loh_lru) {
378 LASSERT(atomic_read(&h->loh_ref) == 0);
380 cfs_hash_bd_get(s->ls_obj_hash, &h->loh_fid, &bd2);
381 LASSERT(bd.bd_bucket == bd2.bd_bucket);
383 cfs_hash_bd_del_locked(s->ls_obj_hash,
385 cfs_list_move(&h->loh_lru, &dispose);
389 if (nr != ~0 && --nr == 0)
392 if (count > 0 && --count == 0)
396 cfs_hash_bd_unlock(s->ls_obj_hash, &bd, 1);
399 * Free everything on the dispose list. This is safe against
400 * races due to the reasons described in lu_object_put().
402 while (!cfs_list_empty(&dispose)) {
403 h = container_of0(dispose.next,
404 struct lu_object_header, loh_lru);
405 cfs_list_del_init(&h->loh_lru);
406 lu_object_free(env, lu_object_top(h));
407 lprocfs_counter_incr(s->ls_stats, LU_SS_LRU_PURGED);
414 if (nr != 0 && did_sth && start != 0) {
415 start = 0; /* restart from the first bucket */
418 /* race on s->ls_purge_start, but nobody cares */
419 s->ls_purge_start = i % CFS_HASH_NBKT(s->ls_obj_hash);
423 EXPORT_SYMBOL(lu_site_purge);
428 * Code below has to jump through certain loops to output object description
429 * into libcfs_debug_msg-based log. The problem is that lu_object_print()
430 * composes object description from strings that are parts of _lines_ of
431 * output (i.e., strings that are not terminated by newline). This doesn't fit
432 * very well into libcfs_debug_msg() interface that assumes that each message
433 * supplied to it is a self-contained output line.
435 * To work around this, strings are collected in a temporary buffer
436 * (implemented as a value of lu_cdebug_key key), until terminating newline
437 * character is detected.
445 * XXX overflow is not handled correctly.
450 struct lu_cdebug_data {
454 char lck_area[LU_CDEBUG_LINE];
457 /* context key constructor/destructor: lu_global_key_init, lu_global_key_fini */
458 LU_KEY_INIT_FINI(lu_global, struct lu_cdebug_data);
461 * Key, holding temporary buffer. This key is registered very early by
464 struct lu_context_key lu_global_key = {
465 .lct_tags = LCT_MD_THREAD | LCT_DT_THREAD |
466 LCT_MG_THREAD | LCT_CL_THREAD | LCT_LOCAL,
467 .lct_init = lu_global_key_init,
468 .lct_fini = lu_global_key_fini
472 * Printer function emitting messages through libcfs_debug_msg().
474 int lu_cdebug_printer(const struct lu_env *env,
475 void *cookie, const char *format, ...)
477 struct libcfs_debug_msg_data *msgdata = cookie;
478 struct lu_cdebug_data *key;
483 va_start(args, format);
485 key = lu_context_key_get(&env->le_ctx, &lu_global_key);
486 LASSERT(key != NULL);
488 used = strlen(key->lck_area);
489 complete = format[strlen(format) - 1] == '\n';
491 * Append new chunk to the buffer.
493 vsnprintf(key->lck_area + used,
494 ARRAY_SIZE(key->lck_area) - used, format, args);
496 if (cfs_cdebug_show(msgdata->msg_mask, msgdata->msg_subsys))
497 libcfs_debug_msg(msgdata, "%s", key->lck_area);
498 key->lck_area[0] = 0;
503 EXPORT_SYMBOL(lu_cdebug_printer);
506 * Print object header.
508 void lu_object_header_print(const struct lu_env *env, void *cookie,
509 lu_printer_t printer,
510 const struct lu_object_header *hdr)
512 (*printer)(env, cookie, "header@%p[%#lx, %d, "DFID"%s%s%s]",
513 hdr, hdr->loh_flags, atomic_read(&hdr->loh_ref),
515 cfs_hlist_unhashed(&hdr->loh_hash) ? "" : " hash",
516 cfs_list_empty((cfs_list_t *)&hdr->loh_lru) ? \
518 hdr->loh_attr & LOHA_EXISTS ? " exist":"");
520 EXPORT_SYMBOL(lu_object_header_print);
523 * Print human readable representation of the \a o to the \a printer.
525 void lu_object_print(const struct lu_env *env, void *cookie,
526 lu_printer_t printer, const struct lu_object *o)
528 static const char ruler[] = "........................................";
529 struct lu_object_header *top;
533 lu_object_header_print(env, cookie, printer, top);
534 (*printer)(env, cookie, "{\n");
536 cfs_list_for_each_entry(o, &top->loh_layers, lo_linkage) {
538 * print `.' \a depth times followed by type name and address
540 (*printer)(env, cookie, "%*.*s%s@%p", depth, depth, ruler,
541 o->lo_dev->ld_type->ldt_name, o);
543 if (o->lo_ops->loo_object_print != NULL)
544 (*o->lo_ops->loo_object_print)(env, cookie, printer, o);
546 (*printer)(env, cookie, "\n");
549 (*printer)(env, cookie, "} header@%p\n", top);
551 EXPORT_SYMBOL(lu_object_print);
554 * Check object consistency.
556 int lu_object_invariant(const struct lu_object *o)
558 struct lu_object_header *top;
561 cfs_list_for_each_entry(o, &top->loh_layers, lo_linkage) {
562 if (o->lo_ops->loo_object_invariant != NULL &&
563 !o->lo_ops->loo_object_invariant(o))
568 EXPORT_SYMBOL(lu_object_invariant);
570 static struct lu_object *htable_lookup(struct lu_site *s,
572 const struct lu_fid *f,
573 wait_queue_t *waiter,
576 struct lu_site_bkt_data *bkt;
577 struct lu_object_header *h;
578 cfs_hlist_node_t *hnode;
579 __u64 ver = cfs_hash_bd_version_get(bd);
582 return ERR_PTR(-ENOENT);
585 bkt = cfs_hash_bd_extra_get(s->ls_obj_hash, bd);
586 /* cfs_hash_bd_peek_locked is a somehow "internal" function
587 * of cfs_hash, it doesn't add refcount on object. */
588 hnode = cfs_hash_bd_peek_locked(s->ls_obj_hash, bd, (void *)f);
590 lprocfs_counter_incr(s->ls_stats, LU_SS_CACHE_MISS);
591 return ERR_PTR(-ENOENT);
594 h = container_of0(hnode, struct lu_object_header, loh_hash);
595 if (likely(!lu_object_is_dying(h))) {
596 cfs_hash_get(s->ls_obj_hash, hnode);
597 lprocfs_counter_incr(s->ls_stats, LU_SS_CACHE_HIT);
598 cfs_list_del_init(&h->loh_lru);
599 return lu_object_top(h);
603 * Lookup found an object being destroyed this object cannot be
604 * returned (to assure that references to dying objects are eventually
605 * drained), and moreover, lookup has to wait until object is freed.
608 init_waitqueue_entry_current(waiter);
609 add_wait_queue(&bkt->lsb_marche_funebre, waiter);
610 set_current_state(TASK_UNINTERRUPTIBLE);
611 lprocfs_counter_incr(s->ls_stats, LU_SS_CACHE_DEATH_RACE);
612 return ERR_PTR(-EAGAIN);
615 static struct lu_object *htable_lookup_nowait(struct lu_site *s,
617 const struct lu_fid *f)
619 cfs_hlist_node_t *hnode;
620 struct lu_object_header *h;
622 /* cfs_hash_bd_peek_locked is a somehow "internal" function
623 * of cfs_hash, it doesn't add refcount on object. */
624 hnode = cfs_hash_bd_peek_locked(s->ls_obj_hash, bd, (void *)f);
626 lprocfs_counter_incr(s->ls_stats, LU_SS_CACHE_MISS);
627 return ERR_PTR(-ENOENT);
630 h = container_of0(hnode, struct lu_object_header, loh_hash);
631 if (unlikely(lu_object_is_dying(h)))
632 return ERR_PTR(-ENOENT);
634 cfs_hash_get(s->ls_obj_hash, hnode);
635 lprocfs_counter_incr(s->ls_stats, LU_SS_CACHE_HIT);
636 cfs_list_del_init(&h->loh_lru);
637 return lu_object_top(h);
641 * Search cache for an object with the fid \a f. If such object is found,
642 * return it. Otherwise, create new object, insert it into cache and return
643 * it. In any case, additional reference is acquired on the returned object.
645 struct lu_object *lu_object_find(const struct lu_env *env,
646 struct lu_device *dev, const struct lu_fid *f,
647 const struct lu_object_conf *conf)
649 return lu_object_find_at(env, dev->ld_site->ls_top_dev, f, conf);
651 EXPORT_SYMBOL(lu_object_find);
654 * Limit the lu_object cache to a maximum of lu_cache_nr objects. Because
655 * the calculation for the number of objects to reclaim is not covered by
656 * a lock the maximum number of objects is capped by LU_CACHE_MAX_ADJUST.
657 * This ensures that many concurrent threads will not accidentally purge
660 static void lu_object_limit(const struct lu_env *env,
661 struct lu_device *dev)
665 if (lu_cache_nr == LU_CACHE_NR_UNLIMITED)
668 size = cfs_hash_size_get(dev->ld_site->ls_obj_hash);
669 nr = (__u64)lu_cache_nr;
671 lu_site_purge(env, dev->ld_site,
672 MIN(size - nr, LU_CACHE_NR_MAX_ADJUST));
677 static struct lu_object *lu_object_new(const struct lu_env *env,
678 struct lu_device *dev,
679 const struct lu_fid *f,
680 const struct lu_object_conf *conf)
685 struct lu_site_bkt_data *bkt;
687 o = lu_object_alloc(env, dev, f, conf);
688 if (unlikely(IS_ERR(o)))
691 hs = dev->ld_site->ls_obj_hash;
692 cfs_hash_bd_get_and_lock(hs, (void *)f, &bd, 1);
693 bkt = cfs_hash_bd_extra_get(hs, &bd);
694 cfs_hash_bd_add_locked(hs, &bd, &o->lo_header->loh_hash);
696 cfs_hash_bd_unlock(hs, &bd, 1);
698 lu_object_limit(env, dev);
704 * Core logic of lu_object_find*() functions.
706 static struct lu_object *lu_object_find_try(const struct lu_env *env,
707 struct lu_device *dev,
708 const struct lu_fid *f,
709 const struct lu_object_conf *conf,
710 wait_queue_t *waiter)
713 struct lu_object *shadow;
720 * This uses standard index maintenance protocol:
722 * - search index under lock, and return object if found;
723 * - otherwise, unlock index, allocate new object;
724 * - lock index and search again;
725 * - if nothing is found (usual case), insert newly created
727 * - otherwise (race: other thread inserted object), free
728 * object just allocated.
732 * For "LOC_F_NEW" case, we are sure the object is new established.
733 * It is unnecessary to perform lookup-alloc-lookup-insert, instead,
734 * just alloc and insert directly.
736 * If dying object is found during index search, add @waiter to the
737 * site wait-queue and return ERR_PTR(-EAGAIN).
739 if (conf != NULL && conf->loc_flags & LOC_F_NEW)
740 return lu_object_new(env, dev, f, conf);
744 cfs_hash_bd_get_and_lock(hs, (void *)f, &bd, 1);
745 o = htable_lookup(s, &bd, f, waiter, &version);
746 cfs_hash_bd_unlock(hs, &bd, 1);
747 if (!IS_ERR(o) || PTR_ERR(o) != -ENOENT)
751 * Allocate new object. This may result in rather complicated
752 * operations, including fld queries, inode loading, etc.
754 o = lu_object_alloc(env, dev, f, conf);
755 if (unlikely(IS_ERR(o)))
758 LASSERT(lu_fid_eq(lu_object_fid(o), f));
760 cfs_hash_bd_lock(hs, &bd, 1);
762 shadow = htable_lookup(s, &bd, f, waiter, &version);
763 if (likely(IS_ERR(shadow) && PTR_ERR(shadow) == -ENOENT)) {
764 struct lu_site_bkt_data *bkt;
766 bkt = cfs_hash_bd_extra_get(hs, &bd);
767 cfs_hash_bd_add_locked(hs, &bd, &o->lo_header->loh_hash);
769 cfs_hash_bd_unlock(hs, &bd, 1);
771 lu_object_limit(env, dev);
776 lprocfs_counter_incr(s->ls_stats, LU_SS_CACHE_RACE);
777 cfs_hash_bd_unlock(hs, &bd, 1);
778 lu_object_free(env, o);
783 * Much like lu_object_find(), but top level device of object is specifically
784 * \a dev rather than top level device of the site. This interface allows
785 * objects of different "stacking" to be created within the same site.
787 struct lu_object *lu_object_find_at(const struct lu_env *env,
788 struct lu_device *dev,
789 const struct lu_fid *f,
790 const struct lu_object_conf *conf)
792 struct lu_site_bkt_data *bkt;
793 struct lu_object *obj;
797 obj = lu_object_find_try(env, dev, f, conf, &wait);
798 if (obj != ERR_PTR(-EAGAIN))
801 * lu_object_find_try() already added waiter into the
804 waitq_wait(&wait, TASK_UNINTERRUPTIBLE);
805 bkt = lu_site_bkt_from_fid(dev->ld_site, (void *)f);
806 remove_wait_queue(&bkt->lsb_marche_funebre, &wait);
809 EXPORT_SYMBOL(lu_object_find_at);
812 * Try to find the object in cache without waiting for the dead object
813 * to be released nor allocating object if no cached one was found.
815 * The found object will be set as LU_OBJECT_HEARD_BANSHEE for purging.
817 void lu_object_purge(const struct lu_env *env, struct lu_device *dev,
818 const struct lu_fid *f)
820 struct lu_site *s = dev->ld_site;
821 cfs_hash_t *hs = s->ls_obj_hash;
825 cfs_hash_bd_get_and_lock(hs, f, &bd, 1);
826 o = htable_lookup_nowait(s, &bd, f);
827 cfs_hash_bd_unlock(hs, &bd, 1);
829 set_bit(LU_OBJECT_HEARD_BANSHEE, &o->lo_header->loh_flags);
830 lu_object_put(env, o);
833 EXPORT_SYMBOL(lu_object_purge);
836 * Find object with given fid, and return its slice belonging to given device.
838 struct lu_object *lu_object_find_slice(const struct lu_env *env,
839 struct lu_device *dev,
840 const struct lu_fid *f,
841 const struct lu_object_conf *conf)
843 struct lu_object *top;
844 struct lu_object *obj;
846 top = lu_object_find(env, dev, f, conf);
848 obj = lu_object_locate(top->lo_header, dev->ld_type);
850 lu_object_put(env, top);
855 EXPORT_SYMBOL(lu_object_find_slice);
858 * Global list of all device types.
860 static CFS_LIST_HEAD(lu_device_types);
862 int lu_device_type_init(struct lu_device_type *ldt)
866 atomic_set(&ldt->ldt_device_nr, 0);
867 INIT_LIST_HEAD(&ldt->ldt_linkage);
868 if (ldt->ldt_ops->ldto_init)
869 result = ldt->ldt_ops->ldto_init(ldt);
872 spin_lock(&obd_types_lock);
873 list_add(&ldt->ldt_linkage, &lu_device_types);
874 spin_unlock(&obd_types_lock);
879 EXPORT_SYMBOL(lu_device_type_init);
881 void lu_device_type_fini(struct lu_device_type *ldt)
883 spin_lock(&obd_types_lock);
884 list_del_init(&ldt->ldt_linkage);
885 spin_unlock(&obd_types_lock);
886 if (ldt->ldt_ops->ldto_fini)
887 ldt->ldt_ops->ldto_fini(ldt);
889 EXPORT_SYMBOL(lu_device_type_fini);
892 * Global list of all sites on this node
894 static CFS_LIST_HEAD(lu_sites);
895 static DEFINE_MUTEX(lu_sites_guard);
898 * Global environment used by site shrinker.
900 static struct lu_env lu_shrink_env;
902 struct lu_site_print_arg {
903 struct lu_env *lsp_env;
905 lu_printer_t lsp_printer;
909 lu_site_obj_print(cfs_hash_t *hs, cfs_hash_bd_t *bd,
910 cfs_hlist_node_t *hnode, void *data)
912 struct lu_site_print_arg *arg = (struct lu_site_print_arg *)data;
913 struct lu_object_header *h;
915 h = cfs_hlist_entry(hnode, struct lu_object_header, loh_hash);
916 if (!cfs_list_empty(&h->loh_layers)) {
917 const struct lu_object *o;
919 o = lu_object_top(h);
920 lu_object_print(arg->lsp_env, arg->lsp_cookie,
921 arg->lsp_printer, o);
923 lu_object_header_print(arg->lsp_env, arg->lsp_cookie,
924 arg->lsp_printer, h);
930 * Print all objects in \a s.
932 void lu_site_print(const struct lu_env *env, struct lu_site *s, void *cookie,
933 lu_printer_t printer)
935 struct lu_site_print_arg arg = {
936 .lsp_env = (struct lu_env *)env,
937 .lsp_cookie = cookie,
938 .lsp_printer = printer,
941 cfs_hash_for_each(s->ls_obj_hash, lu_site_obj_print, &arg);
943 EXPORT_SYMBOL(lu_site_print);
946 * Return desired hash table order.
948 static int lu_htable_order(struct lu_device *top)
950 unsigned long cache_size;
954 * For ZFS based OSDs the cache should be disabled by default. This
955 * allows the ZFS ARC maximum flexibility in determining what buffers
956 * to cache. If Lustre has objects or buffer which it wants to ensure
957 * always stay cached it must maintain a hold on them.
959 if (strcmp(top->ld_type->ldt_name, LUSTRE_OSD_ZFS_NAME) == 0) {
960 lu_cache_percent = 1;
961 lu_cache_nr = LU_CACHE_NR_ZFS_LIMIT;
962 return LU_SITE_BITS_MIN;
966 * Calculate hash table size, assuming that we want reasonable
967 * performance when 20% of total memory is occupied by cache of
970 * Size of lu_object is (arbitrary) taken as 1K (together with inode).
972 cache_size = totalram_pages;
974 #if BITS_PER_LONG == 32
975 /* limit hashtable size for lowmem systems to low RAM */
976 if (cache_size > 1 << (30 - PAGE_CACHE_SHIFT))
977 cache_size = 1 << (30 - PAGE_CACHE_SHIFT) * 3 / 4;
980 /* clear off unreasonable cache setting. */
981 if (lu_cache_percent == 0 || lu_cache_percent > LU_CACHE_PERCENT_MAX) {
982 CWARN("obdclass: invalid lu_cache_percent: %u, it must be in"
983 " the range of (0, %u]. Will use default value: %u.\n",
984 lu_cache_percent, LU_CACHE_PERCENT_MAX,
985 LU_CACHE_PERCENT_DEFAULT);
987 lu_cache_percent = LU_CACHE_PERCENT_DEFAULT;
989 cache_size = cache_size / 100 * lu_cache_percent *
990 (PAGE_CACHE_SIZE / 1024);
992 for (bits = 1; (1 << bits) < cache_size; ++bits) {
998 static unsigned lu_obj_hop_hash(cfs_hash_t *hs,
999 const void *key, unsigned mask)
1001 struct lu_fid *fid = (struct lu_fid *)key;
1004 hash = fid_flatten32(fid);
1005 hash += (hash >> 4) + (hash << 12); /* mixing oid and seq */
1006 hash = hash_long(hash, hs->hs_bkt_bits);
1008 /* give me another random factor */
1009 hash -= hash_long((unsigned long)hs, fid_oid(fid) % 11 + 3);
1011 hash <<= hs->hs_cur_bits - hs->hs_bkt_bits;
1012 hash |= (fid_seq(fid) + fid_oid(fid)) & (CFS_HASH_NBKT(hs) - 1);
1017 static void *lu_obj_hop_object(cfs_hlist_node_t *hnode)
1019 return cfs_hlist_entry(hnode, struct lu_object_header, loh_hash);
1022 static void *lu_obj_hop_key(cfs_hlist_node_t *hnode)
1024 struct lu_object_header *h;
1026 h = cfs_hlist_entry(hnode, struct lu_object_header, loh_hash);
1030 static int lu_obj_hop_keycmp(const void *key, cfs_hlist_node_t *hnode)
1032 struct lu_object_header *h;
1034 h = cfs_hlist_entry(hnode, struct lu_object_header, loh_hash);
1035 return lu_fid_eq(&h->loh_fid, (struct lu_fid *)key);
1038 static void lu_obj_hop_get(cfs_hash_t *hs, cfs_hlist_node_t *hnode)
1040 struct lu_object_header *h;
1042 h = cfs_hlist_entry(hnode, struct lu_object_header, loh_hash);
1043 if (atomic_add_return(1, &h->loh_ref) == 1) {
1044 struct lu_site_bkt_data *bkt;
1047 cfs_hash_bd_get(hs, &h->loh_fid, &bd);
1048 bkt = cfs_hash_bd_extra_get(hs, &bd);
1053 static void lu_obj_hop_put_locked(cfs_hash_t *hs, cfs_hlist_node_t *hnode)
1055 LBUG(); /* we should never called it */
1058 cfs_hash_ops_t lu_site_hash_ops = {
1059 .hs_hash = lu_obj_hop_hash,
1060 .hs_key = lu_obj_hop_key,
1061 .hs_keycmp = lu_obj_hop_keycmp,
1062 .hs_object = lu_obj_hop_object,
1063 .hs_get = lu_obj_hop_get,
1064 .hs_put_locked = lu_obj_hop_put_locked,
1067 void lu_dev_add_linkage(struct lu_site *s, struct lu_device *d)
1069 spin_lock(&s->ls_ld_lock);
1070 if (cfs_list_empty(&d->ld_linkage))
1071 cfs_list_add(&d->ld_linkage, &s->ls_ld_linkage);
1072 spin_unlock(&s->ls_ld_lock);
1074 EXPORT_SYMBOL(lu_dev_add_linkage);
1076 void lu_dev_del_linkage(struct lu_site *s, struct lu_device *d)
1078 spin_lock(&s->ls_ld_lock);
1079 cfs_list_del_init(&d->ld_linkage);
1080 spin_unlock(&s->ls_ld_lock);
1082 EXPORT_SYMBOL(lu_dev_del_linkage);
1085 * Initialize site \a s, with \a d as the top level device.
1087 int lu_site_init(struct lu_site *s, struct lu_device *top)
1089 struct lu_site_bkt_data *bkt;
1096 memset(s, 0, sizeof *s);
1097 bits = lu_htable_order(top);
1098 snprintf(name, 16, "lu_site_%s", top->ld_type->ldt_name);
1099 for (bits = min(max(LU_SITE_BITS_MIN, bits), LU_SITE_BITS_MAX);
1100 bits >= LU_SITE_BITS_MIN; bits--) {
1101 s->ls_obj_hash = cfs_hash_create(name, bits, bits,
1102 bits - LU_SITE_BKT_BITS,
1105 CFS_HASH_SPIN_BKTLOCK |
1106 CFS_HASH_NO_ITEMREF |
1108 CFS_HASH_ASSERT_EMPTY |
1110 if (s->ls_obj_hash != NULL)
1114 if (s->ls_obj_hash == NULL) {
1115 CERROR("failed to create lu_site hash with bits: %d\n", bits);
1119 cfs_hash_for_each_bucket(s->ls_obj_hash, &bd, i) {
1120 bkt = cfs_hash_bd_extra_get(s->ls_obj_hash, &bd);
1121 CFS_INIT_LIST_HEAD(&bkt->lsb_lru);
1122 init_waitqueue_head(&bkt->lsb_marche_funebre);
1125 s->ls_stats = lprocfs_alloc_stats(LU_SS_LAST_STAT, 0);
1126 if (s->ls_stats == NULL) {
1127 cfs_hash_putref(s->ls_obj_hash);
1128 s->ls_obj_hash = NULL;
1132 lprocfs_counter_init(s->ls_stats, LU_SS_CREATED,
1133 0, "created", "created");
1134 lprocfs_counter_init(s->ls_stats, LU_SS_CACHE_HIT,
1135 0, "cache_hit", "cache_hit");
1136 lprocfs_counter_init(s->ls_stats, LU_SS_CACHE_MISS,
1137 0, "cache_miss", "cache_miss");
1138 lprocfs_counter_init(s->ls_stats, LU_SS_CACHE_RACE,
1139 0, "cache_race", "cache_race");
1140 lprocfs_counter_init(s->ls_stats, LU_SS_CACHE_DEATH_RACE,
1141 0, "cache_death_race", "cache_death_race");
1142 lprocfs_counter_init(s->ls_stats, LU_SS_LRU_PURGED,
1143 0, "lru_purged", "lru_purged");
1145 CFS_INIT_LIST_HEAD(&s->ls_linkage);
1146 s->ls_top_dev = top;
1149 lu_ref_add(&top->ld_reference, "site-top", s);
1151 CFS_INIT_LIST_HEAD(&s->ls_ld_linkage);
1152 spin_lock_init(&s->ls_ld_lock);
1154 lu_dev_add_linkage(s, top);
1158 EXPORT_SYMBOL(lu_site_init);
1161 * Finalize \a s and release its resources.
1163 void lu_site_fini(struct lu_site *s)
1165 mutex_lock(&lu_sites_guard);
1166 cfs_list_del_init(&s->ls_linkage);
1167 mutex_unlock(&lu_sites_guard);
1169 if (s->ls_obj_hash != NULL) {
1170 cfs_hash_putref(s->ls_obj_hash);
1171 s->ls_obj_hash = NULL;
1174 if (s->ls_top_dev != NULL) {
1175 s->ls_top_dev->ld_site = NULL;
1176 lu_ref_del(&s->ls_top_dev->ld_reference, "site-top", s);
1177 lu_device_put(s->ls_top_dev);
1178 s->ls_top_dev = NULL;
1181 if (s->ls_stats != NULL)
1182 lprocfs_free_stats(&s->ls_stats);
1184 EXPORT_SYMBOL(lu_site_fini);
1187 * Called when initialization of stack for this site is completed.
1189 int lu_site_init_finish(struct lu_site *s)
1192 mutex_lock(&lu_sites_guard);
1193 result = lu_context_refill(&lu_shrink_env.le_ctx);
1195 cfs_list_add(&s->ls_linkage, &lu_sites);
1196 mutex_unlock(&lu_sites_guard);
1199 EXPORT_SYMBOL(lu_site_init_finish);
1202 * Acquire additional reference on device \a d
1204 void lu_device_get(struct lu_device *d)
1206 atomic_inc(&d->ld_ref);
1208 EXPORT_SYMBOL(lu_device_get);
1211 * Release reference on device \a d.
1213 void lu_device_put(struct lu_device *d)
1215 LASSERT(atomic_read(&d->ld_ref) > 0);
1216 atomic_dec(&d->ld_ref);
1218 EXPORT_SYMBOL(lu_device_put);
1221 * Initialize device \a d of type \a t.
1223 int lu_device_init(struct lu_device *d, struct lu_device_type *t)
1225 if (atomic_inc_return(&t->ldt_device_nr) == 1 &&
1226 t->ldt_ops->ldto_start != NULL)
1227 t->ldt_ops->ldto_start(t);
1229 memset(d, 0, sizeof *d);
1231 lu_ref_init(&d->ld_reference);
1232 INIT_LIST_HEAD(&d->ld_linkage);
1236 EXPORT_SYMBOL(lu_device_init);
1239 * Finalize device \a d.
1241 void lu_device_fini(struct lu_device *d)
1243 struct lu_device_type *t = d->ld_type;
1245 if (d->ld_obd != NULL) {
1246 d->ld_obd->obd_lu_dev = NULL;
1250 lu_ref_fini(&d->ld_reference);
1251 LASSERTF(atomic_read(&d->ld_ref) == 0,
1252 "Refcount is %u\n", atomic_read(&d->ld_ref));
1253 LASSERT(atomic_read(&t->ldt_device_nr) > 0);
1255 if (atomic_dec_and_test(&t->ldt_device_nr) &&
1256 t->ldt_ops->ldto_stop != NULL)
1257 t->ldt_ops->ldto_stop(t);
1259 EXPORT_SYMBOL(lu_device_fini);
1262 * Initialize object \a o that is part of compound object \a h and was created
1265 int lu_object_init(struct lu_object *o, struct lu_object_header *h,
1266 struct lu_device *d)
1268 memset(o, 0, sizeof(*o));
1272 lu_ref_add_at(&d->ld_reference, &o->lo_dev_ref, "lu_object", o);
1273 CFS_INIT_LIST_HEAD(&o->lo_linkage);
1277 EXPORT_SYMBOL(lu_object_init);
1280 * Finalize object and release its resources.
1282 void lu_object_fini(struct lu_object *o)
1284 struct lu_device *dev = o->lo_dev;
1286 LASSERT(cfs_list_empty(&o->lo_linkage));
1289 lu_ref_del_at(&dev->ld_reference, &o->lo_dev_ref,
1295 EXPORT_SYMBOL(lu_object_fini);
1298 * Add object \a o as first layer of compound object \a h
1300 * This is typically called by the ->ldo_object_alloc() method of top-level
1303 void lu_object_add_top(struct lu_object_header *h, struct lu_object *o)
1305 cfs_list_move(&o->lo_linkage, &h->loh_layers);
1307 EXPORT_SYMBOL(lu_object_add_top);
1310 * Add object \a o as a layer of compound object, going after \a before.
1312 * This is typically called by the ->ldo_object_alloc() method of \a
1315 void lu_object_add(struct lu_object *before, struct lu_object *o)
1317 cfs_list_move(&o->lo_linkage, &before->lo_linkage);
1319 EXPORT_SYMBOL(lu_object_add);
1322 * Initialize compound object.
1324 int lu_object_header_init(struct lu_object_header *h)
1326 memset(h, 0, sizeof *h);
1327 atomic_set(&h->loh_ref, 1);
1328 CFS_INIT_HLIST_NODE(&h->loh_hash);
1329 CFS_INIT_LIST_HEAD(&h->loh_lru);
1330 CFS_INIT_LIST_HEAD(&h->loh_layers);
1331 lu_ref_init(&h->loh_reference);
1334 EXPORT_SYMBOL(lu_object_header_init);
1337 * Finalize compound object.
1339 void lu_object_header_fini(struct lu_object_header *h)
1341 LASSERT(cfs_list_empty(&h->loh_layers));
1342 LASSERT(cfs_list_empty(&h->loh_lru));
1343 LASSERT(cfs_hlist_unhashed(&h->loh_hash));
1344 lu_ref_fini(&h->loh_reference);
1346 EXPORT_SYMBOL(lu_object_header_fini);
1349 * Given a compound object, find its slice, corresponding to the device type
1352 struct lu_object *lu_object_locate(struct lu_object_header *h,
1353 const struct lu_device_type *dtype)
1355 struct lu_object *o;
1357 cfs_list_for_each_entry(o, &h->loh_layers, lo_linkage) {
1358 if (o->lo_dev->ld_type == dtype)
1363 EXPORT_SYMBOL(lu_object_locate);
1368 * Finalize and free devices in the device stack.
1370 * Finalize device stack by purging object cache, and calling
1371 * lu_device_type_operations::ldto_device_fini() and
1372 * lu_device_type_operations::ldto_device_free() on all devices in the stack.
1374 void lu_stack_fini(const struct lu_env *env, struct lu_device *top)
1376 struct lu_site *site = top->ld_site;
1377 struct lu_device *scan;
1378 struct lu_device *next;
1380 lu_site_purge(env, site, ~0);
1381 for (scan = top; scan != NULL; scan = next) {
1382 next = scan->ld_type->ldt_ops->ldto_device_fini(env, scan);
1383 lu_ref_del(&scan->ld_reference, "lu-stack", &lu_site_init);
1384 lu_device_put(scan);
1388 lu_site_purge(env, site, ~0);
1390 for (scan = top; scan != NULL; scan = next) {
1391 const struct lu_device_type *ldt = scan->ld_type;
1392 struct obd_type *type;
1394 next = ldt->ldt_ops->ldto_device_free(env, scan);
1395 type = ldt->ldt_obd_type;
1398 class_put_type(type);
1402 EXPORT_SYMBOL(lu_stack_fini);
1406 * Maximal number of tld slots.
1408 LU_CONTEXT_KEY_NR = 40
1411 static struct lu_context_key *lu_keys[LU_CONTEXT_KEY_NR] = { NULL, };
1413 static DEFINE_SPINLOCK(lu_keys_guard);
1416 * Global counter incremented whenever key is registered, unregistered,
1417 * revived or quiesced. This is used to void unnecessary calls to
1418 * lu_context_refill(). No locking is provided, as initialization and shutdown
1419 * are supposed to be externally serialized.
1421 static unsigned key_set_version = 0;
1426 int lu_context_key_register(struct lu_context_key *key)
1431 LASSERT(key->lct_init != NULL);
1432 LASSERT(key->lct_fini != NULL);
1433 LASSERT(key->lct_tags != 0);
1434 LASSERT(key->lct_owner != NULL);
1437 spin_lock(&lu_keys_guard);
1438 for (i = 0; i < ARRAY_SIZE(lu_keys); ++i) {
1439 if (lu_keys[i] == NULL) {
1441 atomic_set(&key->lct_used, 1);
1443 lu_ref_init(&key->lct_reference);
1449 spin_unlock(&lu_keys_guard);
1452 EXPORT_SYMBOL(lu_context_key_register);
1454 static void key_fini(struct lu_context *ctx, int index)
1456 if (ctx->lc_value != NULL && ctx->lc_value[index] != NULL) {
1457 struct lu_context_key *key;
1459 key = lu_keys[index];
1460 LASSERT(key != NULL);
1461 LASSERT(key->lct_fini != NULL);
1462 LASSERT(atomic_read(&key->lct_used) > 1);
1464 key->lct_fini(ctx, key, ctx->lc_value[index]);
1465 lu_ref_del(&key->lct_reference, "ctx", ctx);
1466 atomic_dec(&key->lct_used);
1468 LASSERT(key->lct_owner != NULL);
1469 if ((ctx->lc_tags & LCT_NOREF) == 0) {
1470 LINVRNT(module_refcount(key->lct_owner) > 0);
1471 module_put(key->lct_owner);
1473 ctx->lc_value[index] = NULL;
1480 void lu_context_key_degister(struct lu_context_key *key)
1482 LASSERT(atomic_read(&key->lct_used) >= 1);
1483 LINVRNT(0 <= key->lct_index && key->lct_index < ARRAY_SIZE(lu_keys));
1485 lu_context_key_quiesce(key);
1488 spin_lock(&lu_keys_guard);
1489 key_fini(&lu_shrink_env.le_ctx, key->lct_index);
1490 if (lu_keys[key->lct_index]) {
1491 lu_keys[key->lct_index] = NULL;
1492 lu_ref_fini(&key->lct_reference);
1494 spin_unlock(&lu_keys_guard);
1496 LASSERTF(atomic_read(&key->lct_used) == 1,
1497 "key has instances: %d\n",
1498 atomic_read(&key->lct_used));
1500 EXPORT_SYMBOL(lu_context_key_degister);
1503 * Register a number of keys. This has to be called after all keys have been
1504 * initialized by a call to LU_CONTEXT_KEY_INIT().
1506 int lu_context_key_register_many(struct lu_context_key *k, ...)
1508 struct lu_context_key *key = k;
1514 result = lu_context_key_register(key);
1517 key = va_arg(args, struct lu_context_key *);
1518 } while (key != NULL);
1524 lu_context_key_degister(k);
1525 k = va_arg(args, struct lu_context_key *);
1532 EXPORT_SYMBOL(lu_context_key_register_many);
1535 * De-register a number of keys. This is a dual to
1536 * lu_context_key_register_many().
1538 void lu_context_key_degister_many(struct lu_context_key *k, ...)
1544 lu_context_key_degister(k);
1545 k = va_arg(args, struct lu_context_key*);
1546 } while (k != NULL);
1549 EXPORT_SYMBOL(lu_context_key_degister_many);
1552 * Revive a number of keys.
1554 void lu_context_key_revive_many(struct lu_context_key *k, ...)
1560 lu_context_key_revive(k);
1561 k = va_arg(args, struct lu_context_key*);
1562 } while (k != NULL);
1565 EXPORT_SYMBOL(lu_context_key_revive_many);
1568 * Quiescent a number of keys.
1570 void lu_context_key_quiesce_many(struct lu_context_key *k, ...)
1576 lu_context_key_quiesce(k);
1577 k = va_arg(args, struct lu_context_key*);
1578 } while (k != NULL);
1581 EXPORT_SYMBOL(lu_context_key_quiesce_many);
1584 * Return value associated with key \a key in context \a ctx.
1586 void *lu_context_key_get(const struct lu_context *ctx,
1587 const struct lu_context_key *key)
1589 LINVRNT(ctx->lc_state == LCS_ENTERED);
1590 LINVRNT(0 <= key->lct_index && key->lct_index < ARRAY_SIZE(lu_keys));
1591 LASSERT(lu_keys[key->lct_index] == key);
1592 return ctx->lc_value[key->lct_index];
1594 EXPORT_SYMBOL(lu_context_key_get);
1597 * List of remembered contexts. XXX document me.
1599 static CFS_LIST_HEAD(lu_context_remembered);
1602 * Destroy \a key in all remembered contexts. This is used to destroy key
1603 * values in "shared" contexts (like service threads), when a module owning
1604 * the key is about to be unloaded.
1606 void lu_context_key_quiesce(struct lu_context_key *key)
1608 struct lu_context *ctx;
1609 extern unsigned cl_env_cache_purge(unsigned nr);
1611 if (!(key->lct_tags & LCT_QUIESCENT)) {
1613 * XXX layering violation.
1615 cl_env_cache_purge(~0);
1616 key->lct_tags |= LCT_QUIESCENT;
1618 * XXX memory barrier has to go here.
1620 spin_lock(&lu_keys_guard);
1621 cfs_list_for_each_entry(ctx, &lu_context_remembered,
1623 key_fini(ctx, key->lct_index);
1624 spin_unlock(&lu_keys_guard);
1628 EXPORT_SYMBOL(lu_context_key_quiesce);
1630 void lu_context_key_revive(struct lu_context_key *key)
1632 key->lct_tags &= ~LCT_QUIESCENT;
1635 EXPORT_SYMBOL(lu_context_key_revive);
1637 static void keys_fini(struct lu_context *ctx)
1641 if (ctx->lc_value == NULL)
1644 for (i = 0; i < ARRAY_SIZE(lu_keys); ++i)
1647 OBD_FREE(ctx->lc_value, ARRAY_SIZE(lu_keys) * sizeof ctx->lc_value[0]);
1648 ctx->lc_value = NULL;
1651 static int keys_fill(struct lu_context *ctx)
1655 LINVRNT(ctx->lc_value != NULL);
1656 for (i = 0; i < ARRAY_SIZE(lu_keys); ++i) {
1657 struct lu_context_key *key;
1660 if (ctx->lc_value[i] == NULL && key != NULL &&
1661 (key->lct_tags & ctx->lc_tags) &&
1663 * Don't create values for a LCT_QUIESCENT key, as this
1664 * will pin module owning a key.
1666 !(key->lct_tags & LCT_QUIESCENT)) {
1669 LINVRNT(key->lct_init != NULL);
1670 LINVRNT(key->lct_index == i);
1672 value = key->lct_init(ctx, key);
1673 if (unlikely(IS_ERR(value)))
1674 return PTR_ERR(value);
1676 LASSERT(key->lct_owner != NULL);
1677 if (!(ctx->lc_tags & LCT_NOREF))
1678 try_module_get(key->lct_owner);
1679 lu_ref_add_atomic(&key->lct_reference, "ctx", ctx);
1680 atomic_inc(&key->lct_used);
1682 * This is the only place in the code, where an
1683 * element of ctx->lc_value[] array is set to non-NULL
1686 ctx->lc_value[i] = value;
1687 if (key->lct_exit != NULL)
1688 ctx->lc_tags |= LCT_HAS_EXIT;
1690 ctx->lc_version = key_set_version;
1695 static int keys_init(struct lu_context *ctx)
1697 OBD_ALLOC(ctx->lc_value, ARRAY_SIZE(lu_keys) * sizeof ctx->lc_value[0]);
1698 if (likely(ctx->lc_value != NULL))
1699 return keys_fill(ctx);
1705 * Initialize context data-structure. Create values for all keys.
1707 int lu_context_init(struct lu_context *ctx, __u32 tags)
1711 memset(ctx, 0, sizeof *ctx);
1712 ctx->lc_state = LCS_INITIALIZED;
1713 ctx->lc_tags = tags;
1714 if (tags & LCT_REMEMBER) {
1715 spin_lock(&lu_keys_guard);
1716 cfs_list_add(&ctx->lc_remember, &lu_context_remembered);
1717 spin_unlock(&lu_keys_guard);
1719 CFS_INIT_LIST_HEAD(&ctx->lc_remember);
1722 rc = keys_init(ctx);
1724 lu_context_fini(ctx);
1728 EXPORT_SYMBOL(lu_context_init);
1731 * Finalize context data-structure. Destroy key values.
1733 void lu_context_fini(struct lu_context *ctx)
1735 LINVRNT(ctx->lc_state == LCS_INITIALIZED || ctx->lc_state == LCS_LEFT);
1736 ctx->lc_state = LCS_FINALIZED;
1738 if ((ctx->lc_tags & LCT_REMEMBER) == 0) {
1739 LASSERT(cfs_list_empty(&ctx->lc_remember));
1742 } else { /* could race with key degister */
1743 spin_lock(&lu_keys_guard);
1745 cfs_list_del_init(&ctx->lc_remember);
1746 spin_unlock(&lu_keys_guard);
1749 EXPORT_SYMBOL(lu_context_fini);
1752 * Called before entering context.
1754 void lu_context_enter(struct lu_context *ctx)
1756 LINVRNT(ctx->lc_state == LCS_INITIALIZED || ctx->lc_state == LCS_LEFT);
1757 ctx->lc_state = LCS_ENTERED;
1759 EXPORT_SYMBOL(lu_context_enter);
1762 * Called after exiting from \a ctx
1764 void lu_context_exit(struct lu_context *ctx)
1768 LINVRNT(ctx->lc_state == LCS_ENTERED);
1769 ctx->lc_state = LCS_LEFT;
1770 if (ctx->lc_tags & LCT_HAS_EXIT && ctx->lc_value != NULL) {
1771 for (i = 0; i < ARRAY_SIZE(lu_keys); ++i) {
1772 if (ctx->lc_value[i] != NULL) {
1773 struct lu_context_key *key;
1776 LASSERT(key != NULL);
1777 if (key->lct_exit != NULL)
1779 key, ctx->lc_value[i]);
1784 EXPORT_SYMBOL(lu_context_exit);
1787 * Allocate for context all missing keys that were registered after context
1788 * creation. key_set_version is only changed in rare cases when modules
1789 * are loaded and removed.
1791 int lu_context_refill(struct lu_context *ctx)
1793 return likely(ctx->lc_version == key_set_version) ? 0 : keys_fill(ctx);
1795 EXPORT_SYMBOL(lu_context_refill);
1798 * lu_ctx_tags/lu_ses_tags will be updated if there are new types of
1799 * obd being added. Currently, this is only used on client side, specifically
1800 * for echo device client, for other stack (like ptlrpc threads), context are
1801 * predefined when the lu_device type are registered, during the module probe
1804 __u32 lu_context_tags_default = 0;
1805 __u32 lu_session_tags_default = 0;
1807 void lu_context_tags_update(__u32 tags)
1809 spin_lock(&lu_keys_guard);
1810 lu_context_tags_default |= tags;
1812 spin_unlock(&lu_keys_guard);
1814 EXPORT_SYMBOL(lu_context_tags_update);
1816 void lu_context_tags_clear(__u32 tags)
1818 spin_lock(&lu_keys_guard);
1819 lu_context_tags_default &= ~tags;
1821 spin_unlock(&lu_keys_guard);
1823 EXPORT_SYMBOL(lu_context_tags_clear);
1825 void lu_session_tags_update(__u32 tags)
1827 spin_lock(&lu_keys_guard);
1828 lu_session_tags_default |= tags;
1830 spin_unlock(&lu_keys_guard);
1832 EXPORT_SYMBOL(lu_session_tags_update);
1834 void lu_session_tags_clear(__u32 tags)
1836 spin_lock(&lu_keys_guard);
1837 lu_session_tags_default &= ~tags;
1839 spin_unlock(&lu_keys_guard);
1841 EXPORT_SYMBOL(lu_session_tags_clear);
1843 int lu_env_init(struct lu_env *env, __u32 tags)
1848 result = lu_context_init(&env->le_ctx, tags);
1849 if (likely(result == 0))
1850 lu_context_enter(&env->le_ctx);
1853 EXPORT_SYMBOL(lu_env_init);
1855 void lu_env_fini(struct lu_env *env)
1857 lu_context_exit(&env->le_ctx);
1858 lu_context_fini(&env->le_ctx);
1861 EXPORT_SYMBOL(lu_env_fini);
1863 int lu_env_refill(struct lu_env *env)
1867 result = lu_context_refill(&env->le_ctx);
1868 if (result == 0 && env->le_ses != NULL)
1869 result = lu_context_refill(env->le_ses);
1872 EXPORT_SYMBOL(lu_env_refill);
1875 * Currently, this API will only be used by echo client.
1876 * Because echo client and normal lustre client will share
1877 * same cl_env cache. So echo client needs to refresh
1878 * the env context after it get one from the cache, especially
1879 * when normal client and echo client co-exist in the same client.
1881 int lu_env_refill_by_tags(struct lu_env *env, __u32 ctags,
1886 if ((env->le_ctx.lc_tags & ctags) != ctags) {
1887 env->le_ctx.lc_version = 0;
1888 env->le_ctx.lc_tags |= ctags;
1891 if (env->le_ses && (env->le_ses->lc_tags & stags) != stags) {
1892 env->le_ses->lc_version = 0;
1893 env->le_ses->lc_tags |= stags;
1896 result = lu_env_refill(env);
1900 EXPORT_SYMBOL(lu_env_refill_by_tags);
1902 static struct shrinker *lu_site_shrinker;
1904 typedef struct lu_site_stats{
1905 unsigned lss_populated;
1906 unsigned lss_max_search;
1911 static void lu_site_stats_get(cfs_hash_t *hs,
1912 lu_site_stats_t *stats, int populated)
1917 cfs_hash_for_each_bucket(hs, &bd, i) {
1918 struct lu_site_bkt_data *bkt = cfs_hash_bd_extra_get(hs, &bd);
1919 cfs_hlist_head_t *hhead;
1921 cfs_hash_bd_lock(hs, &bd, 1);
1922 stats->lss_busy += bkt->lsb_busy;
1923 stats->lss_total += cfs_hash_bd_count_get(&bd);
1924 stats->lss_max_search = max((int)stats->lss_max_search,
1925 cfs_hash_bd_depmax_get(&bd));
1927 cfs_hash_bd_unlock(hs, &bd, 1);
1931 cfs_hash_bd_for_each_hlist(hs, &bd, hhead) {
1932 if (!cfs_hlist_empty(hhead))
1933 stats->lss_populated++;
1935 cfs_hash_bd_unlock(hs, &bd, 1);
1941 static unsigned long lu_cache_shrink_count(struct shrinker *sk,
1942 struct shrink_control *sc)
1944 lu_site_stats_t stats;
1946 struct lu_site *tmp;
1947 unsigned long cached = 0;
1949 if (!(sc->gfp_mask & __GFP_FS))
1952 mutex_lock(&lu_sites_guard);
1953 list_for_each_entry_safe(s, tmp, &lu_sites, ls_linkage) {
1954 memset(&stats, 0, sizeof(stats));
1955 lu_site_stats_get(s->ls_obj_hash, &stats, 0);
1956 cached += stats.lss_total - stats.lss_busy;
1958 mutex_unlock(&lu_sites_guard);
1960 cached = (cached / 100) * sysctl_vfs_cache_pressure;
1961 CDEBUG(D_INODE, "%ld objects cached\n", cached);
1965 static unsigned long lu_cache_shrink_scan(struct shrinker *sk,
1966 struct shrink_control *sc)
1969 struct lu_site *tmp;
1970 unsigned long remain = sc->nr_to_scan;
1973 if (!(sc->gfp_mask & __GFP_FS))
1974 /* We must not take the lu_sites_guard lock when
1975 * __GFP_FS is *not* set because of the deadlock
1976 * possibility detailed above. Additionally,
1977 * since we cannot determine the number of
1978 * objects in the cache without taking this
1979 * lock, we're in a particularly tough spot. As
1980 * a result, we'll just lie and say our cache is
1981 * empty. This _should_ be ok, as we can't
1982 * reclaim objects when __GFP_FS is *not* set
1987 mutex_lock(&lu_sites_guard);
1988 list_for_each_entry_safe(s, tmp, &lu_sites, ls_linkage) {
1989 remain = lu_site_purge(&lu_shrink_env, s, remain);
1991 * Move just shrunk site to the tail of site list to
1992 * assure shrinking fairness.
1994 list_move_tail(&s->ls_linkage, &splice);
1996 list_splice(&splice, lu_sites.prev);
1997 mutex_unlock(&lu_sites_guard);
1999 return sc->nr_to_scan - remain;
2002 #ifndef HAVE_SHRINKER_COUNT
2004 * There exists a potential lock inversion deadlock scenario when using
2005 * Lustre on top of ZFS. This occurs between one of ZFS's
2006 * buf_hash_table.ht_lock's, and Lustre's lu_sites_guard lock. Essentially,
2007 * thread A will take the lu_sites_guard lock and sleep on the ht_lock,
2008 * while thread B will take the ht_lock and sleep on the lu_sites_guard
2009 * lock. Obviously neither thread will wake and drop their respective hold
2012 * To prevent this from happening we must ensure the lu_sites_guard lock is
2013 * not taken while down this code path. ZFS reliably does not set the
2014 * __GFP_FS bit in its code paths, so this can be used to determine if it
2015 * is safe to take the lu_sites_guard lock.
2017 * Ideally we should accurately return the remaining number of cached
2018 * objects without taking the lu_sites_guard lock, but this is not
2019 * possible in the current implementation.
2021 static int lu_cache_shrink(SHRINKER_ARGS(sc, nr_to_scan, gfp_mask))
2024 struct shrink_control scv = {
2025 .nr_to_scan = shrink_param(sc, nr_to_scan),
2026 .gfp_mask = shrink_param(sc, gfp_mask)
2028 #if !defined(HAVE_SHRINKER_WANT_SHRINK_PTR) && !defined(HAVE_SHRINK_CONTROL)
2029 struct shrinker* shrinker = NULL;
2033 CDEBUG(D_INODE, "Shrink %lu objects\n", scv.nr_to_scan);
2035 lu_cache_shrink_scan(shrinker, &scv);
2037 cached = lu_cache_shrink_count(shrinker, &scv);
2038 if (scv.nr_to_scan == 0)
2039 CDEBUG(D_INODE, "%d objects cached\n", cached);
2043 #endif /* HAVE_SHRINKER_COUNT */
2051 * Environment to be used in debugger, contains all tags.
2053 struct lu_env lu_debugging_env;
2056 * Debugging printer function using printk().
2058 int lu_printk_printer(const struct lu_env *env,
2059 void *unused, const char *format, ...)
2063 va_start(args, format);
2064 vprintk(format, args);
2069 int lu_debugging_setup(void)
2071 return lu_env_init(&lu_debugging_env, ~0);
2074 void lu_context_keys_dump(void)
2078 for (i = 0; i < ARRAY_SIZE(lu_keys); ++i) {
2079 struct lu_context_key *key;
2083 CERROR("[%d]: %p %x (%p,%p,%p) %d %d \"%s\"@%p\n",
2084 i, key, key->lct_tags,
2085 key->lct_init, key->lct_fini, key->lct_exit,
2086 key->lct_index, atomic_read(&key->lct_used),
2087 key->lct_owner ? key->lct_owner->name : "",
2089 lu_ref_print(&key->lct_reference);
2093 EXPORT_SYMBOL(lu_context_keys_dump);
2094 #endif /* __KERNEL__ */
2097 * Initialization of global lu_* data.
2099 int lu_global_init(void)
2102 DEF_SHRINKER_VAR(shvar, lu_cache_shrink,
2103 lu_cache_shrink_count, lu_cache_shrink_scan);
2105 CDEBUG(D_INFO, "Lustre LU module (%p).\n", &lu_keys);
2107 result = lu_ref_global_init();
2111 LU_CONTEXT_KEY_INIT(&lu_global_key);
2112 result = lu_context_key_register(&lu_global_key);
2117 * At this level, we don't know what tags are needed, so allocate them
2118 * conservatively. This should not be too bad, because this
2119 * environment is global.
2121 mutex_lock(&lu_sites_guard);
2122 result = lu_env_init(&lu_shrink_env, LCT_SHRINKER);
2123 mutex_unlock(&lu_sites_guard);
2128 * seeks estimation: 3 seeks to read a record from oi, one to read
2129 * inode, one for ea. Unfortunately setting this high value results in
2130 * lu_object/inode cache consuming all the memory.
2132 lu_site_shrinker = set_shrinker(DEFAULT_SEEKS, &shvar);
2133 if (lu_site_shrinker == NULL)
2140 * Dual to lu_global_init().
2142 void lu_global_fini(void)
2144 if (lu_site_shrinker != NULL) {
2145 remove_shrinker(lu_site_shrinker);
2146 lu_site_shrinker = NULL;
2149 lu_context_key_degister(&lu_global_key);
2152 * Tear shrinker environment down _after_ de-registering
2153 * lu_global_key, because the latter has a value in the former.
2155 mutex_lock(&lu_sites_guard);
2156 lu_env_fini(&lu_shrink_env);
2157 mutex_unlock(&lu_sites_guard);
2159 lu_ref_global_fini();
2162 static __u32 ls_stats_read(struct lprocfs_stats *stats, int idx)
2165 struct lprocfs_counter ret;
2167 lprocfs_stats_collect(stats, idx, &ret);
2168 return (__u32)ret.lc_count;
2175 * Output site statistical counters into a buffer. Suitable for
2176 * lprocfs_rd_*()-style functions.
2178 int lu_site_stats_seq_print(const struct lu_site *s, struct seq_file *m)
2180 lu_site_stats_t stats;
2182 memset(&stats, 0, sizeof(stats));
2183 lu_site_stats_get(s->ls_obj_hash, &stats, 1);
2185 return seq_printf(m, "%d/%d %d/%d %d %d %d %d %d %d %d\n",
2188 stats.lss_populated,
2189 CFS_HASH_NHLIST(s->ls_obj_hash),
2190 stats.lss_max_search,
2191 ls_stats_read(s->ls_stats, LU_SS_CREATED),
2192 ls_stats_read(s->ls_stats, LU_SS_CACHE_HIT),
2193 ls_stats_read(s->ls_stats, LU_SS_CACHE_MISS),
2194 ls_stats_read(s->ls_stats, LU_SS_CACHE_RACE),
2195 ls_stats_read(s->ls_stats, LU_SS_CACHE_DEATH_RACE),
2196 ls_stats_read(s->ls_stats, LU_SS_LRU_PURGED));
2198 EXPORT_SYMBOL(lu_site_stats_seq_print);
2200 int lu_site_stats_print(const struct lu_site *s, char *page, int count)
2202 lu_site_stats_t stats;
2204 memset(&stats, 0, sizeof(stats));
2205 lu_site_stats_get(s->ls_obj_hash, &stats, 1);
2207 return snprintf(page, count, "%d/%d %d/%d %d %d %d %d %d %d %d\n",
2210 stats.lss_populated,
2211 CFS_HASH_NHLIST(s->ls_obj_hash),
2212 stats.lss_max_search,
2213 ls_stats_read(s->ls_stats, LU_SS_CREATED),
2214 ls_stats_read(s->ls_stats, LU_SS_CACHE_HIT),
2215 ls_stats_read(s->ls_stats, LU_SS_CACHE_MISS),
2216 ls_stats_read(s->ls_stats, LU_SS_CACHE_RACE),
2217 ls_stats_read(s->ls_stats, LU_SS_CACHE_DEATH_RACE),
2218 ls_stats_read(s->ls_stats, LU_SS_LRU_PURGED));
2220 EXPORT_SYMBOL(lu_site_stats_print);
2223 * Helper function to initialize a number of kmem slab caches at once.
2225 int lu_kmem_init(struct lu_kmem_descr *caches)
2228 struct lu_kmem_descr *iter = caches;
2230 for (result = 0; iter->ckd_cache != NULL; ++iter) {
2231 *iter->ckd_cache = kmem_cache_create(iter->ckd_name,
2234 if (*iter->ckd_cache == NULL) {
2236 /* free all previously allocated caches */
2237 lu_kmem_fini(caches);
2243 EXPORT_SYMBOL(lu_kmem_init);
2246 * Helper function to finalize a number of kmem slab cached at once. Dual to
2249 void lu_kmem_fini(struct lu_kmem_descr *caches)
2251 for (; caches->ckd_cache != NULL; ++caches) {
2252 if (*caches->ckd_cache != NULL) {
2253 kmem_cache_destroy(*caches->ckd_cache);
2254 *caches->ckd_cache = NULL;
2258 EXPORT_SYMBOL(lu_kmem_fini);
2261 * Temporary solution to be able to assign fid in ->do_create()
2262 * till we have fully-functional OST fids
2264 void lu_object_assign_fid(const struct lu_env *env, struct lu_object *o,
2265 const struct lu_fid *fid)
2267 struct lu_site *s = o->lo_dev->ld_site;
2268 struct lu_fid *old = &o->lo_header->loh_fid;
2269 struct lu_site_bkt_data *bkt;
2270 struct lu_object *shadow;
2271 wait_queue_t waiter;
2276 LASSERT(fid_is_zero(old));
2278 hs = s->ls_obj_hash;
2279 cfs_hash_bd_get_and_lock(hs, (void *)fid, &bd, 1);
2280 shadow = htable_lookup(s, &bd, fid, &waiter, &version);
2281 /* supposed to be unique */
2282 LASSERT(IS_ERR(shadow) && PTR_ERR(shadow) == -ENOENT);
2284 bkt = cfs_hash_bd_extra_get(hs, &bd);
2285 cfs_hash_bd_add_locked(hs, &bd, &o->lo_header->loh_hash);
2287 cfs_hash_bd_unlock(hs, &bd, 1);
2289 EXPORT_SYMBOL(lu_object_assign_fid);
2292 * allocates object with 0 (non-assiged) fid
2293 * XXX: temporary solution to be able to assign fid in ->do_create()
2294 * till we have fully-functional OST fids
2296 struct lu_object *lu_object_anon(const struct lu_env *env,
2297 struct lu_device *dev,
2298 const struct lu_object_conf *conf)
2301 struct lu_object *o;
2304 o = lu_object_alloc(env, dev, &fid, conf);
2308 EXPORT_SYMBOL(lu_object_anon);
2310 struct lu_buf LU_BUF_NULL = {
2314 EXPORT_SYMBOL(LU_BUF_NULL);
2316 void lu_buf_free(struct lu_buf *buf)
2320 LASSERT(buf->lb_len > 0);
2321 OBD_FREE_LARGE(buf->lb_buf, buf->lb_len);
2326 EXPORT_SYMBOL(lu_buf_free);
2328 void lu_buf_alloc(struct lu_buf *buf, int size)
2331 LASSERT(buf->lb_buf == NULL);
2332 LASSERT(buf->lb_len == 0);
2333 OBD_ALLOC_LARGE(buf->lb_buf, size);
2334 if (likely(buf->lb_buf))
2337 EXPORT_SYMBOL(lu_buf_alloc);
2339 void lu_buf_realloc(struct lu_buf *buf, int size)
2342 lu_buf_alloc(buf, size);
2344 EXPORT_SYMBOL(lu_buf_realloc);
2346 struct lu_buf *lu_buf_check_and_alloc(struct lu_buf *buf, int len)
2348 if (buf->lb_buf == NULL && buf->lb_len == 0)
2349 lu_buf_alloc(buf, len);
2351 if ((len > buf->lb_len) && (buf->lb_buf != NULL))
2352 lu_buf_realloc(buf, len);
2356 EXPORT_SYMBOL(lu_buf_check_and_alloc);
2359 * Increase the size of the \a buf.
2360 * preserves old data in buffer
2361 * old buffer remains unchanged on error
2362 * \retval 0 or -ENOMEM
2364 int lu_buf_check_and_grow(struct lu_buf *buf, int len)
2368 if (len <= buf->lb_len)
2371 OBD_ALLOC_LARGE(ptr, len);
2375 /* Free the old buf */
2376 if (buf->lb_buf != NULL) {
2377 memcpy(ptr, buf->lb_buf, buf->lb_len);
2378 OBD_FREE_LARGE(buf->lb_buf, buf->lb_len);
2385 EXPORT_SYMBOL(lu_buf_check_and_grow);