X-Git-Url: https://git.whamcloud.com/?p=fs%2Flustre-release.git;a=blobdiff_plain;f=lustre%2Fobdclass%2Flu_object.c;h=fbe034a898dc2008e3a2bc935d6ea2cb82abc115;hp=f577dca735d8eb4976e84b8ae5a25f96f47d77a4;hb=bf86b80e4eacd0734665aa818d9cdebf0c157ee1;hpb=6f34d6b85466bc8cddb8de1816734528af9da09b diff --git a/lustre/obdclass/lu_object.c b/lustre/obdclass/lu_object.c index f577dca..fbe034a 100644 --- a/lustre/obdclass/lu_object.c +++ b/lustre/obdclass/lu_object.c @@ -15,11 +15,7 @@ * * You should have received a copy of the GNU General Public License * version 2 along with this program; If not, see - * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf - * - * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, - * CA 95054 USA or visit www.sun.com if you need additional information or - * have any questions. + * http://www.gnu.org/licenses/gpl-2.0.html * * GPL HEADER END */ @@ -27,7 +23,7 @@ * Copyright (c) 2007, 2010, Oracle and/or its affiliates. All rights reserved. * Use is subject to license terms. * - * Copyright (c) 2011, 2012, Whamcloud, Inc. + * Copyright (c) 2011, 2017, Intel Corporation. */ /* * This file is part of Lustre, http://www.lustre.org/ @@ -44,24 +40,90 @@ #define DEBUG_SUBSYSTEM S_CLASS -#include - -#ifdef __KERNEL__ -# include +#include +#include +#ifdef HAVE_PROCESSOR_H +#include +#else +#include #endif -/* hash_long() */ -#include +#include +#include /* hash_long() */ +#include #include #include #include #include #include -#include -/* lu_time_global_{init,fini}() */ -#include +#include + +struct lu_site_bkt_data { + /** + * LRU list, updated on each access to object. Protected by + * bucket lock of lu_site::ls_obj_hash. + * + * "Cold" end of LRU is lu_site::ls_lru.next. Accessed object are + * moved to the lu_site::ls_lru.prev (this is due to the non-existence + * of list_for_each_entry_safe_reverse()). + */ + struct list_head lsb_lru; + /** + * Wait-queue signaled when an object in this site is ultimately + * destroyed (lu_object_free()). It is used by lu_object_find() to + * wait before re-trying when object in the process of destruction is + * found in the hash table. + * + * \see htable_lookup(). + */ + wait_queue_head_t lsb_marche_funebre; +}; + +enum { + LU_CACHE_PERCENT_MAX = 50, + LU_CACHE_PERCENT_DEFAULT = 20 +}; + +#define LU_CACHE_NR_MAX_ADJUST 512 +#define LU_CACHE_NR_UNLIMITED -1 +#define LU_CACHE_NR_DEFAULT LU_CACHE_NR_UNLIMITED +#define LU_CACHE_NR_LDISKFS_LIMIT LU_CACHE_NR_UNLIMITED +/** This is set to roughly (20 * OSS_NTHRS_MAX) to prevent thrashing */ +#define LU_CACHE_NR_ZFS_LIMIT 10240 + +#define LU_SITE_BITS_MIN 12 +#define LU_SITE_BITS_MAX 24 +#define LU_SITE_BITS_MAX_CL 19 +/** + * total 256 buckets, we don't want too many buckets because: + * - consume too much memory + * - avoid unbalanced LRU list + */ +#define LU_SITE_BKT_BITS 8 + + +static unsigned int lu_cache_percent = LU_CACHE_PERCENT_DEFAULT; +module_param(lu_cache_percent, int, 0644); +MODULE_PARM_DESC(lu_cache_percent, "Percentage of memory to be used as lu_object cache"); + +static long lu_cache_nr = LU_CACHE_NR_DEFAULT; +module_param(lu_cache_nr, long, 0644); +MODULE_PARM_DESC(lu_cache_nr, "Maximum number of objects in lu_object cache"); static void lu_object_free(const struct lu_env *env, struct lu_object *o); +static __u32 ls_stats_read(struct lprocfs_stats *stats, int idx); + +wait_queue_head_t * +lu_site_wq_from_fid(struct lu_site *site, struct lu_fid *fid) +{ + struct cfs_hash_bd bd; + struct lu_site_bkt_data *bkt; + + cfs_hash_bd_get(site->ls_obj_hash, fid, &bd); + bkt = cfs_hash_bd_extra_get(site->ls_obj_hash, &bd); + return &bkt->lsb_marche_funebre; +} +EXPORT_SYMBOL(lu_site_wq_from_fid); /** * Decrease reference counter on object. If last reference is freed, return @@ -70,30 +132,26 @@ static void lu_object_free(const struct lu_env *env, struct lu_object *o); */ void lu_object_put(const struct lu_env *env, struct lu_object *o) { - struct lu_site_bkt_data *bkt; - struct lu_object_header *top; - struct lu_site *site; - struct lu_object *orig; - cfs_hash_bd_t bd; - const struct lu_fid *fid; - - top = o->lo_header; - site = o->lo_dev->ld_site; - orig = o; + struct lu_site_bkt_data *bkt; + struct lu_object_header *top = o->lo_header; + struct lu_site *site = o->lo_dev->ld_site; + struct lu_object *orig = o; + struct cfs_hash_bd bd; + const struct lu_fid *fid = lu_object_fid(o); + bool is_dying; /* * till we have full fids-on-OST implemented anonymous objects * are possible in OSP. such an object isn't listed in the site * so we should not remove it from the site. */ - fid = lu_object_fid(o); if (fid_is_zero(fid)) { LASSERT(top->loh_hash.next == NULL && top->loh_hash.pprev == NULL); - LASSERT(cfs_list_empty(&top->loh_lru)); - if (!cfs_atomic_dec_and_test(&top->loh_ref)) + LASSERT(list_empty(&top->loh_lru)); + if (!atomic_dec_and_test(&top->loh_ref)) return; - cfs_list_for_each_entry_reverse(o, &top->loh_layers, lo_linkage) { + list_for_each_entry_reverse(o, &top->loh_layers, lo_linkage) { if (o->lo_ops->loo_object_release != NULL) o->lo_ops->loo_object_release(env, o); } @@ -101,57 +159,69 @@ void lu_object_put(const struct lu_env *env, struct lu_object *o) return; } - cfs_hash_bd_get(site->ls_obj_hash, &top->loh_fid, &bd); - bkt = cfs_hash_bd_extra_get(site->ls_obj_hash, &bd); - - if (!cfs_hash_bd_dec_and_lock(site->ls_obj_hash, &bd, &top->loh_ref)) { - if (lu_object_is_dying(top)) { - - /* - * somebody may be waiting for this, currently only - * used for cl_object, see cl_object_put_last(). - */ - cfs_waitq_broadcast(&bkt->lsb_marche_funebre); - } - return; - } + cfs_hash_bd_get(site->ls_obj_hash, &top->loh_fid, &bd); + bkt = cfs_hash_bd_extra_get(site->ls_obj_hash, &bd); + + is_dying = lu_object_is_dying(top); + if (!cfs_hash_bd_dec_and_lock(site->ls_obj_hash, &bd, &top->loh_ref)) { + /* at this point the object reference is dropped and lock is + * not taken, so lu_object should not be touched because it + * can be freed by concurrent thread. Use local variable for + * check. + */ + if (is_dying) { + /* + * somebody may be waiting for this, currently only + * used for cl_object, see cl_object_put_last(). + */ + wake_up_all(&bkt->lsb_marche_funebre); + } + return; + } - LASSERT(bkt->lsb_busy > 0); - bkt->lsb_busy--; - /* - * When last reference is released, iterate over object - * layers, and notify them that object is no longer busy. - */ - cfs_list_for_each_entry_reverse(o, &top->loh_layers, lo_linkage) { - if (o->lo_ops->loo_object_release != NULL) - o->lo_ops->loo_object_release(env, o); - } + /* + * When last reference is released, iterate over object + * layers, and notify them that object is no longer busy. + */ + list_for_each_entry_reverse(o, &top->loh_layers, lo_linkage) { + if (o->lo_ops->loo_object_release != NULL) + o->lo_ops->loo_object_release(env, o); + } - if (!lu_object_is_dying(top)) { - LASSERT(cfs_list_empty(&top->loh_lru)); - cfs_list_add_tail(&top->loh_lru, &bkt->lsb_lru); - cfs_hash_bd_unlock(site->ls_obj_hash, &bd, 1); - return; - } + /* don't use local 'is_dying' here because if was taken without lock + * but here we need the latest actual value of it so check lu_object + * directly here. + */ + if (!lu_object_is_dying(top) && + (lu_object_exists(orig) || lu_object_is_cl(orig))) { + LASSERT(list_empty(&top->loh_lru)); + list_add_tail(&top->loh_lru, &bkt->lsb_lru); + percpu_counter_inc(&site->ls_lru_len_counter); + CDEBUG(D_INODE, "Add %p/%p to site lru. hash: %p, bkt: %p\n", + orig, top, site->ls_obj_hash, bkt); + cfs_hash_bd_unlock(site->ls_obj_hash, &bd, 1); + return; + } - /* - * If object is dying (will not be cached), removed it - * from hash table and LRU. - * - * This is done with hash table and LRU lists locked. As the only - * way to acquire first reference to previously unreferenced - * object is through hash-table lookup (lu_object_find()), - * or LRU scanning (lu_site_purge()), that are done under hash-table - * and LRU lock, no race with concurrent object lookup is possible - * and we can safely destroy object below. - */ - cfs_hash_bd_del_locked(site->ls_obj_hash, &bd, &top->loh_hash); - cfs_hash_bd_unlock(site->ls_obj_hash, &bd, 1); - /* - * Object was already removed from hash and lru above, can - * kill it. - */ - lu_object_free(env, orig); + /* + * If object is dying (will not be cached) then remove it + * from hash table and LRU. + * + * This is done with hash table and LRU lists locked. As the only + * way to acquire first reference to previously unreferenced + * object is through hash-table lookup (lu_object_find()), + * or LRU scanning (lu_site_purge()), that are done under hash-table + * and LRU lock, no race with concurrent object lookup is possible + * and we can safely destroy object below. + */ + if (!test_and_set_bit(LU_OBJECT_UNHASHED, &top->loh_flags)) + cfs_hash_bd_del_locked(site->ls_obj_hash, &bd, &top->loh_hash); + cfs_hash_bd_unlock(site->ls_obj_hash, &bd, 1); + /* + * Object was already removed from hash and lru above, can + * kill it. + */ + lu_object_free(env, orig); } EXPORT_SYMBOL(lu_object_put); @@ -161,65 +231,100 @@ EXPORT_SYMBOL(lu_object_put); */ void lu_object_put_nocache(const struct lu_env *env, struct lu_object *o) { - set_bit(LU_OBJECT_HEARD_BANSHEE, - &o->lo_header->loh_flags); + set_bit(LU_OBJECT_HEARD_BANSHEE, &o->lo_header->loh_flags); return lu_object_put(env, o); } EXPORT_SYMBOL(lu_object_put_nocache); /** + * Kill the object and take it out of LRU cache. + * Currently used by client code for layout change. + */ +void lu_object_unhash(const struct lu_env *env, struct lu_object *o) +{ + struct lu_object_header *top; + + top = o->lo_header; + set_bit(LU_OBJECT_HEARD_BANSHEE, &top->loh_flags); + if (!test_and_set_bit(LU_OBJECT_UNHASHED, &top->loh_flags)) { + struct lu_site *site = o->lo_dev->ld_site; + struct cfs_hash *obj_hash = site->ls_obj_hash; + struct cfs_hash_bd bd; + + cfs_hash_bd_get_and_lock(obj_hash, &top->loh_fid, &bd, 1); + if (!list_empty(&top->loh_lru)) { + struct lu_site_bkt_data *bkt; + + list_del_init(&top->loh_lru); + bkt = cfs_hash_bd_extra_get(obj_hash, &bd); + percpu_counter_dec(&site->ls_lru_len_counter); + } + cfs_hash_bd_del_locked(obj_hash, &bd, &top->loh_hash); + cfs_hash_bd_unlock(obj_hash, &bd, 1); + } +} +EXPORT_SYMBOL(lu_object_unhash); + +/** * Allocate new object. * * This follows object creation protocol, described in the comment within * struct lu_device_operations definition. */ static struct lu_object *lu_object_alloc(const struct lu_env *env, - struct lu_device *dev, - const struct lu_fid *f, - const struct lu_object_conf *conf) -{ - struct lu_object *scan; - struct lu_object *top; - cfs_list_t *layers; - int clean; - int result; - ENTRY; + struct lu_device *dev, + const struct lu_fid *f, + const struct lu_object_conf *conf) +{ + struct lu_object *scan; + struct lu_object *top; + struct list_head *layers; + unsigned int init_mask = 0; + unsigned int init_flag; + int clean; + int result; + ENTRY; - /* - * Create top-level object slice. This will also create - * lu_object_header. - */ - top = dev->ld_ops->ldo_object_alloc(env, NULL, dev); - if (top == NULL) - RETURN(ERR_PTR(-ENOMEM)); + /* + * Create top-level object slice. This will also create + * lu_object_header. + */ + top = dev->ld_ops->ldo_object_alloc(env, NULL, dev); + if (top == NULL) + RETURN(ERR_PTR(-ENOMEM)); + if (IS_ERR(top)) + RETURN(top); /* * This is the only place where object fid is assigned. It's constant * after this point. */ - LASSERT(fid_is_igif(f) || fid_ver(f) == 0); top->lo_header->loh_fid = *f; layers = &top->lo_header->loh_layers; - do { - /* - * Call ->loo_object_init() repeatedly, until no more new - * object slices are created. - */ - clean = 1; - cfs_list_for_each_entry(scan, layers, lo_linkage) { - if (scan->lo_flags & LU_OBJECT_ALLOCATED) - continue; - clean = 0; - scan->lo_header = top->lo_header; - result = scan->lo_ops->loo_object_init(env, scan, conf); - if (result != 0) { - lu_object_free(env, top); - RETURN(ERR_PTR(result)); - } - scan->lo_flags |= LU_OBJECT_ALLOCATED; - } - } while (!clean); - cfs_list_for_each_entry_reverse(scan, layers, lo_linkage) { + do { + /* + * Call ->loo_object_init() repeatedly, until no more new + * object slices are created. + */ + clean = 1; + init_flag = 1; + list_for_each_entry(scan, layers, lo_linkage) { + if (init_mask & init_flag) + goto next; + clean = 0; + scan->lo_header = top->lo_header; + result = scan->lo_ops->loo_object_init(env, scan, conf); + if (result != 0) { + lu_object_free(env, top); + RETURN(ERR_PTR(result)); + } + init_mask |= init_flag; +next: + init_flag <<= 1; + } + } while (!clean); + + list_for_each_entry_reverse(scan, layers, lo_linkage) { if (scan->lo_ops->loo_object_start != NULL) { result = scan->lo_ops->loo_object_start(env, scan); if (result != 0) { @@ -238,19 +343,19 @@ static struct lu_object *lu_object_alloc(const struct lu_env *env, */ static void lu_object_free(const struct lu_env *env, struct lu_object *o) { - struct lu_site_bkt_data *bkt; - struct lu_site *site; - struct lu_object *scan; - cfs_list_t *layers; - cfs_list_t splice; - - site = o->lo_dev->ld_site; - layers = &o->lo_header->loh_layers; - bkt = lu_site_bkt_from_fid(site, &o->lo_header->loh_fid); + wait_queue_head_t *wq; + struct lu_site *site; + struct lu_object *scan; + struct list_head *layers; + struct list_head splice; + + site = o->lo_dev->ld_site; + layers = &o->lo_header->loh_layers; + wq = lu_site_wq_from_fid(site, &o->lo_header->loh_fid); /* * First call ->loo_object_delete() method to release all resources. */ - cfs_list_for_each_entry_reverse(scan, layers, lo_linkage) { + list_for_each_entry_reverse(scan, layers, lo_linkage) { if (scan->lo_ops->loo_object_delete != NULL) scan->lo_ops->loo_object_delete(env, scan); } @@ -261,49 +366,65 @@ static void lu_object_free(const struct lu_env *env, struct lu_object *o) * necessary, because lu_object_header is freed together with the * top-level slice. */ - CFS_INIT_LIST_HEAD(&splice); - cfs_list_splice_init(layers, &splice); - while (!cfs_list_empty(&splice)) { - /* - * Free layers in bottom-to-top order, so that object header - * lives as long as possible and ->loo_object_free() methods - * can look at its contents. - */ - o = container_of0(splice.prev, struct lu_object, lo_linkage); - cfs_list_del_init(&o->lo_linkage); - LASSERT(o->lo_ops->loo_object_free != NULL); - o->lo_ops->loo_object_free(env, o); - } + INIT_LIST_HEAD(&splice); + list_splice_init(layers, &splice); + while (!list_empty(&splice)) { + /* + * Free layers in bottom-to-top order, so that object header + * lives as long as possible and ->loo_object_free() methods + * can look at its contents. + */ + o = container_of0(splice.prev, struct lu_object, lo_linkage); + list_del_init(&o->lo_linkage); + LASSERT(o->lo_ops->loo_object_free != NULL); + o->lo_ops->loo_object_free(env, o); + } - if (cfs_waitq_active(&bkt->lsb_marche_funebre)) - cfs_waitq_broadcast(&bkt->lsb_marche_funebre); + if (waitqueue_active(wq)) + wake_up_all(wq); } /** * Free \a nr objects from the cold end of the site LRU list. + * if canblock is 0, then don't block awaiting for another + * instance of lu_site_purge() to complete */ -int lu_site_purge(const struct lu_env *env, struct lu_site *s, int nr) +int lu_site_purge_objects(const struct lu_env *env, struct lu_site *s, + int nr, int canblock) { struct lu_object_header *h; struct lu_object_header *temp; struct lu_site_bkt_data *bkt; - cfs_hash_bd_t bd; - cfs_hash_bd_t bd2; - cfs_list_t dispose; - int did_sth; - int start; + struct cfs_hash_bd bd; + struct cfs_hash_bd bd2; + struct list_head dispose; + int did_sth; + unsigned int start = 0; int count; int bnr; - int i; + unsigned int i; - CFS_INIT_LIST_HEAD(&dispose); + if (OBD_FAIL_CHECK(OBD_FAIL_OBD_NO_LRU)) + RETURN(0); + + INIT_LIST_HEAD(&dispose); /* * Under LRU list lock, scan LRU list and move unreferenced objects to * the dispose list, removing them from LRU and hash table. */ - start = s->ls_purge_start; - bnr = (nr == ~0) ? -1 : nr / CFS_HASH_NBKT(s->ls_obj_hash) + 1; + if (nr != ~0) + start = s->ls_purge_start; + bnr = (nr == ~0) ? -1 : nr / (int)CFS_HASH_NBKT(s->ls_obj_hash) + 1; again: + /* + * It doesn't make any sense to make purge threads parallel, that can + * only bring troubles to us. See LU-5331. + */ + if (canblock != 0) + mutex_lock(&s->ls_purge_mutex); + else if (mutex_trylock(&s->ls_purge_mutex) == 0) + goto out; + did_sth = 0; cfs_hash_for_each_bucket(s->ls_obj_hash, &bd, i) { if (i < start) @@ -312,15 +433,16 @@ int lu_site_purge(const struct lu_env *env, struct lu_site *s, int nr) cfs_hash_bd_lock(s->ls_obj_hash, &bd, 1); bkt = cfs_hash_bd_extra_get(s->ls_obj_hash, &bd); - cfs_list_for_each_entry_safe(h, temp, &bkt->lsb_lru, loh_lru) { - LASSERT(cfs_atomic_read(&h->loh_ref) == 0); + list_for_each_entry_safe(h, temp, &bkt->lsb_lru, loh_lru) { + LASSERT(atomic_read(&h->loh_ref) == 0); cfs_hash_bd_get(s->ls_obj_hash, &h->loh_fid, &bd2); LASSERT(bd.bd_bucket == bd2.bd_bucket); cfs_hash_bd_del_locked(s->ls_obj_hash, &bd2, &h->loh_hash); - cfs_list_move(&h->loh_lru, &dispose); + list_move(&h->loh_lru, &dispose); + percpu_counter_dec(&s->ls_lru_len_counter); if (did_sth == 0) did_sth = 1; @@ -330,24 +452,25 @@ int lu_site_purge(const struct lu_env *env, struct lu_site *s, int nr) if (count > 0 && --count == 0) break; - } - cfs_hash_bd_unlock(s->ls_obj_hash, &bd, 1); - cfs_cond_resched(); - /* - * Free everything on the dispose list. This is safe against - * races due to the reasons described in lu_object_put(). - */ - while (!cfs_list_empty(&dispose)) { - h = container_of0(dispose.next, - struct lu_object_header, loh_lru); - cfs_list_del_init(&h->loh_lru); - lu_object_free(env, lu_object_top(h)); - lprocfs_counter_incr(s->ls_stats, LU_SS_LRU_PURGED); - } + } + cfs_hash_bd_unlock(s->ls_obj_hash, &bd, 1); + cond_resched(); + /* + * Free everything on the dispose list. This is safe against + * races due to the reasons described in lu_object_put(). + */ + while (!list_empty(&dispose)) { + h = container_of0(dispose.next, + struct lu_object_header, loh_lru); + list_del_init(&h->loh_lru); + lu_object_free(env, lu_object_top(h)); + lprocfs_counter_incr(s->ls_stats, LU_SS_LRU_PURGED); + } if (nr == 0) break; } + mutex_unlock(&s->ls_purge_mutex); if (nr != 0 && did_sth && start != 0) { start = 0; /* restart from the first bucket */ @@ -356,9 +479,10 @@ int lu_site_purge(const struct lu_env *env, struct lu_site *s, int nr) /* race on s->ls_purge_start, but nobody cares */ s->ls_purge_start = i % CFS_HASH_NBKT(s->ls_obj_hash); +out: return nr; } -EXPORT_SYMBOL(lu_site_purge); +EXPORT_SYMBOL(lu_site_purge_objects); /* * Object printing. @@ -399,11 +523,11 @@ LU_KEY_INIT_FINI(lu_global, struct lu_cdebug_data); * Key, holding temporary buffer. This key is registered very early by * lu_global_init(). */ -struct lu_context_key lu_global_key = { - .lct_tags = LCT_MD_THREAD | LCT_DT_THREAD | - LCT_MG_THREAD | LCT_CL_THREAD, - .lct_init = lu_global_key_init, - .lct_fini = lu_global_key_fini +static struct lu_context_key lu_global_key = { + .lct_tags = LCT_MD_THREAD | LCT_DT_THREAD | + LCT_MG_THREAD | LCT_CL_THREAD | LCT_LOCAL, + .lct_init = lu_global_key_init, + .lct_fini = lu_global_key_fini }; /** @@ -431,8 +555,8 @@ int lu_cdebug_printer(const struct lu_env *env, vsnprintf(key->lck_area + used, ARRAY_SIZE(key->lck_area) - used, format, args); if (complete) { - if (cfs_cdebug_show(msgdata->msg_mask, msgdata->msg_subsys)) - libcfs_debug_msg(msgdata, "%s", key->lck_area); + if (cfs_cdebug_show(msgdata->msg_mask, msgdata->msg_subsys)) + libcfs_debug_msg(msgdata, "%s\n", key->lck_area); key->lck_area[0] = 0; } va_end(args); @@ -447,13 +571,13 @@ void lu_object_header_print(const struct lu_env *env, void *cookie, lu_printer_t printer, const struct lu_object_header *hdr) { - (*printer)(env, cookie, "header@%p[%#lx, %d, "DFID"%s%s%s]", - hdr, hdr->loh_flags, cfs_atomic_read(&hdr->loh_ref), - PFID(&hdr->loh_fid), - cfs_hlist_unhashed(&hdr->loh_hash) ? "" : " hash", - cfs_list_empty((cfs_list_t *)&hdr->loh_lru) ? \ - "" : " lru", - hdr->loh_attr & LOHA_EXISTS ? " exist":""); + (*printer)(env, cookie, "header@%p[%#lx, %d, "DFID"%s%s%s]", + hdr, hdr->loh_flags, atomic_read(&hdr->loh_ref), + PFID(&hdr->loh_fid), + hlist_unhashed(&hdr->loh_hash) ? "" : " hash", + list_empty((struct list_head *)&hdr->loh_lru) ? \ + "" : " lru", + hdr->loh_attr & LOHA_EXISTS ? " exist" : ""); } EXPORT_SYMBOL(lu_object_header_print); @@ -461,28 +585,30 @@ EXPORT_SYMBOL(lu_object_header_print); * Print human readable representation of the \a o to the \a printer. */ void lu_object_print(const struct lu_env *env, void *cookie, - lu_printer_t printer, const struct lu_object *o) + lu_printer_t printer, const struct lu_object *o) { - static const char ruler[] = "........................................"; - struct lu_object_header *top; - int depth; + static const char ruler[] = "........................................"; + struct lu_object_header *top; + int depth = 4; - top = o->lo_header; - lu_object_header_print(env, cookie, printer, top); - (*printer)(env, cookie, "{ \n"); - cfs_list_for_each_entry(o, &top->loh_layers, lo_linkage) { - depth = o->lo_depth + 4; + top = o->lo_header; + lu_object_header_print(env, cookie, printer, top); + (*printer)(env, cookie, "{\n"); - /* - * print `.' \a depth times followed by type name and address - */ - (*printer)(env, cookie, "%*.*s%s@%p", depth, depth, ruler, - o->lo_dev->ld_type->ldt_name, o); - if (o->lo_ops->loo_object_print != NULL) - o->lo_ops->loo_object_print(env, cookie, printer, o); - (*printer)(env, cookie, "\n"); - } - (*printer)(env, cookie, "} header@%p\n", top); + list_for_each_entry(o, &top->loh_layers, lo_linkage) { + /* + * print `.' \a depth times followed by type name and address + */ + (*printer)(env, cookie, "%*.*s%s@%p", depth, depth, ruler, + o->lo_dev->ld_type->ldt_name, o); + + if (o->lo_ops->loo_object_print != NULL) + (*o->lo_ops->loo_object_print)(env, cookie, printer, o); + + (*printer)(env, cookie, "\n"); + } + + (*printer)(env, cookie, "} header@%p\n", top); } EXPORT_SYMBOL(lu_object_print); @@ -494,58 +620,45 @@ int lu_object_invariant(const struct lu_object *o) struct lu_object_header *top; top = o->lo_header; - cfs_list_for_each_entry(o, &top->loh_layers, lo_linkage) { + list_for_each_entry(o, &top->loh_layers, lo_linkage) { if (o->lo_ops->loo_object_invariant != NULL && !o->lo_ops->loo_object_invariant(o)) return 0; } return 1; } -EXPORT_SYMBOL(lu_object_invariant); static struct lu_object *htable_lookup(struct lu_site *s, - cfs_hash_bd_t *bd, - const struct lu_fid *f, - cfs_waitlink_t *waiter, - __u64 *version) + struct cfs_hash_bd *bd, + const struct lu_fid *f, + __u64 *version) { - struct lu_site_bkt_data *bkt; - struct lu_object_header *h; - cfs_hlist_node_t *hnode; - __u64 ver = cfs_hash_bd_version_get(bd); + struct lu_site_bkt_data *bkt; + struct lu_object_header *h; + struct hlist_node *hnode; + __u64 ver = cfs_hash_bd_version_get(bd); - if (*version == ver) - return NULL; + if (*version == ver) + return ERR_PTR(-ENOENT); - *version = ver; - bkt = cfs_hash_bd_extra_get(s->ls_obj_hash, bd); + *version = ver; + bkt = cfs_hash_bd_extra_get(s->ls_obj_hash, bd); /* cfs_hash_bd_peek_locked is a somehow "internal" function * of cfs_hash, it doesn't add refcount on object. */ hnode = cfs_hash_bd_peek_locked(s->ls_obj_hash, bd, (void *)f); - if (hnode == NULL) { - lprocfs_counter_incr(s->ls_stats, LU_SS_CACHE_MISS); - return NULL; - } - - h = container_of0(hnode, struct lu_object_header, loh_hash); - if (likely(!lu_object_is_dying(h))) { - cfs_hash_get(s->ls_obj_hash, hnode); - lprocfs_counter_incr(s->ls_stats, LU_SS_CACHE_HIT); - cfs_list_del_init(&h->loh_lru); - return lu_object_top(h); - } - - /* - * Lookup found an object being destroyed this object cannot be - * returned (to assure that references to dying objects are eventually - * drained), and moreover, lookup has to wait until object is freed. - */ + if (!hnode) { + lprocfs_counter_incr(s->ls_stats, LU_SS_CACHE_MISS); + return ERR_PTR(-ENOENT); + } - cfs_waitlink_init(waiter); - cfs_waitq_add(&bkt->lsb_marche_funebre, waiter); - cfs_set_current_state(CFS_TASK_UNINT); - lprocfs_counter_incr(s->ls_stats, LU_SS_CACHE_DEATH_RACE); - return ERR_PTR(-EAGAIN); + h = container_of0(hnode, struct lu_object_header, loh_hash); + cfs_hash_get(s->ls_obj_hash, hnode); + lprocfs_counter_incr(s->ls_stats, LU_SS_CACHE_HIT); + if (!list_empty(&h->loh_lru)) { + list_del_init(&h->loh_lru); + percpu_counter_dec(&s->ls_lru_len_counter); + } + return lu_object_top(h); } /** @@ -561,131 +674,107 @@ struct lu_object *lu_object_find(const struct lu_env *env, } EXPORT_SYMBOL(lu_object_find); -static struct lu_object *lu_object_new(const struct lu_env *env, - struct lu_device *dev, - const struct lu_fid *f, - const struct lu_object_conf *conf) +/* + * Limit the lu_object cache to a maximum of lu_cache_nr objects. Because + * the calculation for the number of objects to reclaim is not covered by + * a lock the maximum number of objects is capped by LU_CACHE_MAX_ADJUST. + * This ensures that many concurrent threads will not accidentally purge + * the entire cache. + */ +static void lu_object_limit(const struct lu_env *env, + struct lu_device *dev) { - struct lu_object *o; - cfs_hash_t *hs; - cfs_hash_bd_t bd; - struct lu_site_bkt_data *bkt; + __u64 size, nr; - o = lu_object_alloc(env, dev, f, conf); - if (unlikely(IS_ERR(o))) - return o; + if (lu_cache_nr == LU_CACHE_NR_UNLIMITED) + return; + + size = cfs_hash_size_get(dev->ld_site->ls_obj_hash); + nr = (__u64)lu_cache_nr; + if (size <= nr) + return; - hs = dev->ld_site->ls_obj_hash; - cfs_hash_bd_get_and_lock(hs, (void *)f, &bd, 1); - bkt = cfs_hash_bd_extra_get(hs, &bd); - cfs_hash_bd_add_locked(hs, &bd, &o->lo_header->loh_hash); - bkt->lsb_busy++; - cfs_hash_bd_unlock(hs, &bd, 1); - return o; + lu_site_purge_objects(env, dev->ld_site, + MIN(size - nr, LU_CACHE_NR_MAX_ADJUST), 0); } /** * Core logic of lu_object_find*() functions. + * + * Much like lu_object_find(), but top level device of object is specifically + * \a dev rather than top level device of the site. This interface allows + * objects of different "stacking" to be created within the same site. */ -static struct lu_object *lu_object_find_try(const struct lu_env *env, - struct lu_device *dev, - const struct lu_fid *f, - const struct lu_object_conf *conf, - cfs_waitlink_t *waiter) +struct lu_object *lu_object_find_at(const struct lu_env *env, + struct lu_device *dev, + const struct lu_fid *f, + const struct lu_object_conf *conf) { - struct lu_object *o; - struct lu_object *shadow; - struct lu_site *s; - cfs_hash_t *hs; - cfs_hash_bd_t bd; - __u64 version = 0; - - /* - * This uses standard index maintenance protocol: - * - * - search index under lock, and return object if found; - * - otherwise, unlock index, allocate new object; - * - lock index and search again; - * - if nothing is found (usual case), insert newly created - * object into index; - * - otherwise (race: other thread inserted object), free - * object just allocated. - * - unlock index; - * - return object. - * - * For "LOC_F_NEW" case, we are sure the object is new established. - * It is unnecessary to perform lookup-alloc-lookup-insert, instead, - * just alloc and insert directly. - * - * If dying object is found during index search, add @waiter to the - * site wait-queue and return ERR_PTR(-EAGAIN). - */ - if (conf != NULL && conf->loc_flags & LOC_F_NEW) - return lu_object_new(env, dev, f, conf); + struct lu_object *o; + struct lu_object *shadow; + struct lu_site *s; + struct cfs_hash *hs; + struct cfs_hash_bd bd; + __u64 version = 0; - s = dev->ld_site; - hs = s->ls_obj_hash; - cfs_hash_bd_get_and_lock(hs, (void *)f, &bd, 1); - o = htable_lookup(s, &bd, f, waiter, &version); - cfs_hash_bd_unlock(hs, &bd, 1); - if (o != NULL) - return o; + /* + * This uses standard index maintenance protocol: + * + * - search index under lock, and return object if found; + * - otherwise, unlock index, allocate new object; + * - lock index and search again; + * - if nothing is found (usual case), insert newly created + * object into index; + * - otherwise (race: other thread inserted object), free + * object just allocated. + * - unlock index; + * - return object. + * + * For "LOC_F_NEW" case, we are sure the object is new established. + * It is unnecessary to perform lookup-alloc-lookup-insert, instead, + * just alloc and insert directly. + * + */ + s = dev->ld_site; + hs = s->ls_obj_hash; + cfs_hash_bd_get(hs, f, &bd); + if (!(conf && conf->loc_flags & LOC_F_NEW)) { + cfs_hash_bd_lock(hs, &bd, 1); + o = htable_lookup(s, &bd, f, &version); + cfs_hash_bd_unlock(hs, &bd, 1); + + if (!IS_ERR(o) || PTR_ERR(o) != -ENOENT) + return o; + } + /* + * Allocate new object. This may result in rather complicated + * operations, including fld queries, inode loading, etc. + */ + o = lu_object_alloc(env, dev, f, conf); + if (IS_ERR(o)) + return o; - /* - * Allocate new object. This may result in rather complicated - * operations, including fld queries, inode loading, etc. - */ - o = lu_object_alloc(env, dev, f, conf); - if (unlikely(IS_ERR(o))) - return o; + LASSERT(lu_fid_eq(lu_object_fid(o), f)); - LASSERT(lu_fid_eq(lu_object_fid(o), f)); + cfs_hash_bd_lock(hs, &bd, 1); - cfs_hash_bd_lock(hs, &bd, 1); + if (conf && conf->loc_flags & LOC_F_NEW) + shadow = ERR_PTR(-ENOENT); + else + shadow = htable_lookup(s, &bd, f, &version); + if (likely(PTR_ERR(shadow) == -ENOENT)) { + cfs_hash_bd_add_locked(hs, &bd, &o->lo_header->loh_hash); + cfs_hash_bd_unlock(hs, &bd, 1); - shadow = htable_lookup(s, &bd, f, waiter, &version); - if (likely(shadow == NULL)) { - struct lu_site_bkt_data *bkt; + lu_object_limit(env, dev); - bkt = cfs_hash_bd_extra_get(hs, &bd); - cfs_hash_bd_add_locked(hs, &bd, &o->lo_header->loh_hash); - bkt->lsb_busy++; - cfs_hash_bd_unlock(hs, &bd, 1); - return o; - } - - lprocfs_counter_incr(s->ls_stats, LU_SS_CACHE_RACE); - cfs_hash_bd_unlock(hs, &bd, 1); - lu_object_free(env, o); - return shadow; -} - -/** - * Much like lu_object_find(), but top level device of object is specifically - * \a dev rather than top level device of the site. This interface allows - * objects of different "stacking" to be created within the same site. - */ -struct lu_object *lu_object_find_at(const struct lu_env *env, - struct lu_device *dev, - const struct lu_fid *f, - const struct lu_object_conf *conf) -{ - struct lu_site_bkt_data *bkt; - struct lu_object *obj; - cfs_waitlink_t wait; + return o; + } - while (1) { - obj = lu_object_find_try(env, dev, f, conf, &wait); - if (obj != ERR_PTR(-EAGAIN)) - return obj; - /* - * lu_object_find_try() already added waiter into the - * wait queue. - */ - cfs_waitq_wait(&wait, CFS_TASK_UNINT); - bkt = lu_site_bkt_from_fid(dev->ld_site, (void *)f); - cfs_waitq_del(&bkt->lsb_marche_funebre, &wait); - } + lprocfs_counter_incr(s->ls_stats, LU_SS_CACHE_RACE); + cfs_hash_bd_unlock(hs, &bd, 1); + lu_object_free(env, o); + return shadow; } EXPORT_SYMBOL(lu_object_find_at); @@ -697,62 +786,47 @@ struct lu_object *lu_object_find_slice(const struct lu_env *env, const struct lu_fid *f, const struct lu_object_conf *conf) { - struct lu_object *top; - struct lu_object *obj; + struct lu_object *top; + struct lu_object *obj; + + top = lu_object_find(env, dev, f, conf); + if (IS_ERR(top)) + return top; + + obj = lu_object_locate(top->lo_header, dev->ld_type); + if (unlikely(obj == NULL)) { + lu_object_put(env, top); + obj = ERR_PTR(-ENOENT); + } - top = lu_object_find(env, dev, f, conf); - if (!IS_ERR(top)) { - obj = lu_object_locate(top->lo_header, dev->ld_type); - if (obj == NULL) - lu_object_put(env, top); - } else - obj = top; - return obj; + return obj; } EXPORT_SYMBOL(lu_object_find_slice); -/** - * Global list of all device types. - */ -static CFS_LIST_HEAD(lu_device_types); - int lu_device_type_init(struct lu_device_type *ldt) { int result = 0; - CFS_INIT_LIST_HEAD(&ldt->ldt_linkage); + atomic_set(&ldt->ldt_device_nr, 0); if (ldt->ldt_ops->ldto_init) result = ldt->ldt_ops->ldto_init(ldt); - if (result == 0) - cfs_list_add(&ldt->ldt_linkage, &lu_device_types); + return result; } EXPORT_SYMBOL(lu_device_type_init); void lu_device_type_fini(struct lu_device_type *ldt) { - cfs_list_del_init(&ldt->ldt_linkage); if (ldt->ldt_ops->ldto_fini) ldt->ldt_ops->ldto_fini(ldt); } EXPORT_SYMBOL(lu_device_type_fini); -void lu_types_stop(void) -{ - struct lu_device_type *ldt; - - cfs_list_for_each_entry(ldt, &lu_device_types, ldt_linkage) { - if (ldt->ldt_device_nr == 0 && ldt->ldt_ops->ldto_stop) - ldt->ldt_ops->ldto_stop(ldt); - } -} -EXPORT_SYMBOL(lu_types_stop); - /** * Global list of all sites on this node */ -static CFS_LIST_HEAD(lu_sites); -static DEFINE_MUTEX(lu_sites_guard); +static LIST_HEAD(lu_sites); +static DECLARE_RWSEM(lu_sites_guard); /** * Global environment used by site shrinker. @@ -766,24 +840,24 @@ struct lu_site_print_arg { }; static int -lu_site_obj_print(cfs_hash_t *hs, cfs_hash_bd_t *bd, - cfs_hlist_node_t *hnode, void *data) -{ - struct lu_site_print_arg *arg = (struct lu_site_print_arg *)data; - struct lu_object_header *h; - - h = cfs_hlist_entry(hnode, struct lu_object_header, loh_hash); - if (!cfs_list_empty(&h->loh_layers)) { - const struct lu_object *o; - - o = lu_object_top(h); - lu_object_print(arg->lsp_env, arg->lsp_cookie, - arg->lsp_printer, o); - } else { - lu_object_header_print(arg->lsp_env, arg->lsp_cookie, - arg->lsp_printer, h); - } - return 0; +lu_site_obj_print(struct cfs_hash *hs, struct cfs_hash_bd *bd, + struct hlist_node *hnode, void *data) +{ + struct lu_site_print_arg *arg = (struct lu_site_print_arg *)data; + struct lu_object_header *h; + + h = hlist_entry(hnode, struct lu_object_header, loh_hash); + if (!list_empty(&h->loh_layers)) { + const struct lu_object *o; + + o = lu_object_top(h); + lu_object_print(arg->lsp_env, arg->lsp_cookie, + arg->lsp_printer, o); + } else { + lu_object_header_print(arg->lsp_env, arg->lsp_cookie, + arg->lsp_printer, h); + } + return 0; } /** @@ -802,22 +876,29 @@ void lu_site_print(const struct lu_env *env, struct lu_site *s, void *cookie, } EXPORT_SYMBOL(lu_site_print); -enum { - LU_CACHE_PERCENT_MAX = 50, - LU_CACHE_PERCENT_DEFAULT = 20 -}; - -static unsigned int lu_cache_percent = LU_CACHE_PERCENT_DEFAULT; -CFS_MODULE_PARM(lu_cache_percent, "i", int, 0644, - "Percentage of memory to be used as lu_object cache"); - /** * Return desired hash table order. */ -static int lu_htable_order(void) +static unsigned long lu_htable_order(struct lu_device *top) { - unsigned long cache_size; - int bits; + unsigned long cache_size; + unsigned long bits; + unsigned long bits_max = LU_SITE_BITS_MAX; + + /* + * For ZFS based OSDs the cache should be disabled by default. This + * allows the ZFS ARC maximum flexibility in determining what buffers + * to cache. If Lustre has objects or buffer which it wants to ensure + * always stay cached it must maintain a hold on them. + */ + if (strcmp(top->ld_type->ldt_name, LUSTRE_OSD_ZFS_NAME) == 0) { + lu_cache_percent = 1; + lu_cache_nr = LU_CACHE_NR_ZFS_LIMIT; + return LU_SITE_BITS_MIN; + } + + if (strcmp(top->ld_type->ldt_name, LUSTRE_VVP_NAME) == 0) + bits_max = LU_SITE_BITS_MAX_CL; /* * Calculate hash table size, assuming that we want reasonable @@ -826,12 +907,12 @@ static int lu_htable_order(void) * * Size of lu_object is (arbitrary) taken as 1K (together with inode). */ - cache_size = cfs_num_physpages; + cache_size = totalram_pages; #if BITS_PER_LONG == 32 /* limit hashtable size for lowmem systems to low RAM */ - if (cache_size > 1 << (30 - CFS_PAGE_SHIFT)) - cache_size = 1 << (30 - CFS_PAGE_SHIFT) * 3 / 4; + if (cache_size > 1 << (30 - PAGE_SHIFT)) + cache_size = 1 << (30 - PAGE_SHIFT) * 3 / 4; #endif /* clear off unreasonable cache setting. */ @@ -844,75 +925,69 @@ static int lu_htable_order(void) lu_cache_percent = LU_CACHE_PERCENT_DEFAULT; } cache_size = cache_size / 100 * lu_cache_percent * - (CFS_PAGE_SIZE / 1024); + (PAGE_SIZE / 1024); for (bits = 1; (1 << bits) < cache_size; ++bits) { ; } - return bits; + + return clamp_t(typeof(bits), bits, LU_SITE_BITS_MIN, bits_max); } -static unsigned lu_obj_hop_hash(cfs_hash_t *hs, - const void *key, unsigned mask) +static unsigned lu_obj_hop_hash(struct cfs_hash *hs, + const void *key, unsigned mask) { - struct lu_fid *fid = (struct lu_fid *)key; - __u32 hash; + struct lu_fid *fid = (struct lu_fid *)key; + __u32 hash; - hash = fid_flatten32(fid); - hash += (hash >> 4) + (hash << 12); /* mixing oid and seq */ - hash = cfs_hash_long(hash, hs->hs_bkt_bits); + hash = fid_flatten32(fid); + hash += (hash >> 4) + (hash << 12); /* mixing oid and seq */ + hash = hash_long(hash, hs->hs_bkt_bits); - /* give me another random factor */ - hash -= cfs_hash_long((unsigned long)hs, fid_oid(fid) % 11 + 3); + /* give me another random factor */ + hash -= hash_long((unsigned long)hs, fid_oid(fid) % 11 + 3); - hash <<= hs->hs_cur_bits - hs->hs_bkt_bits; - hash |= (fid_seq(fid) + fid_oid(fid)) & (CFS_HASH_NBKT(hs) - 1); + hash <<= hs->hs_cur_bits - hs->hs_bkt_bits; + hash |= (fid_seq(fid) + fid_oid(fid)) & (CFS_HASH_NBKT(hs) - 1); - return hash & mask; + return hash & mask; } -static void *lu_obj_hop_object(cfs_hlist_node_t *hnode) +static void *lu_obj_hop_object(struct hlist_node *hnode) { - return cfs_hlist_entry(hnode, struct lu_object_header, loh_hash); + return hlist_entry(hnode, struct lu_object_header, loh_hash); } -static void *lu_obj_hop_key(cfs_hlist_node_t *hnode) +static void *lu_obj_hop_key(struct hlist_node *hnode) { - struct lu_object_header *h; + struct lu_object_header *h; - h = cfs_hlist_entry(hnode, struct lu_object_header, loh_hash); - return &h->loh_fid; + h = hlist_entry(hnode, struct lu_object_header, loh_hash); + return &h->loh_fid; } -static int lu_obj_hop_keycmp(const void *key, cfs_hlist_node_t *hnode) +static int lu_obj_hop_keycmp(const void *key, struct hlist_node *hnode) { - struct lu_object_header *h; + struct lu_object_header *h; - h = cfs_hlist_entry(hnode, struct lu_object_header, loh_hash); - return lu_fid_eq(&h->loh_fid, (struct lu_fid *)key); + h = hlist_entry(hnode, struct lu_object_header, loh_hash); + return lu_fid_eq(&h->loh_fid, (struct lu_fid *)key); } -static void lu_obj_hop_get(cfs_hash_t *hs, cfs_hlist_node_t *hnode) +static void lu_obj_hop_get(struct cfs_hash *hs, struct hlist_node *hnode) { - struct lu_object_header *h; - - h = cfs_hlist_entry(hnode, struct lu_object_header, loh_hash); - if (cfs_atomic_add_return(1, &h->loh_ref) == 1) { - struct lu_site_bkt_data *bkt; - cfs_hash_bd_t bd; + struct lu_object_header *h; - cfs_hash_bd_get(hs, &h->loh_fid, &bd); - bkt = cfs_hash_bd_extra_get(hs, &bd); - bkt->lsb_busy++; - } + h = hlist_entry(hnode, struct lu_object_header, loh_hash); + atomic_inc(&h->loh_ref); } -static void lu_obj_hop_put_locked(cfs_hash_t *hs, cfs_hlist_node_t *hnode) +static void lu_obj_hop_put_locked(struct cfs_hash *hs, struct hlist_node *hnode) { LBUG(); /* we should never called it */ } -cfs_hash_ops_t lu_site_hash_ops = { +static struct cfs_hash_ops lu_site_hash_ops = { .hs_hash = lu_obj_hop_hash, .hs_key = lu_obj_hop_key, .hs_keycmp = lu_obj_hop_keycmp, @@ -924,8 +999,8 @@ cfs_hash_ops_t lu_site_hash_ops = { void lu_dev_add_linkage(struct lu_site *s, struct lu_device *d) { spin_lock(&s->ls_ld_lock); - if (cfs_list_empty(&d->ld_linkage)) - cfs_list_add(&d->ld_linkage, &s->ls_ld_linkage); + if (list_empty(&d->ld_linkage)) + list_add(&d->ld_linkage, &s->ls_ld_linkage); spin_unlock(&s->ls_ld_lock); } EXPORT_SYMBOL(lu_dev_add_linkage); @@ -933,59 +1008,61 @@ EXPORT_SYMBOL(lu_dev_add_linkage); void lu_dev_del_linkage(struct lu_site *s, struct lu_device *d) { spin_lock(&s->ls_ld_lock); - cfs_list_del_init(&d->ld_linkage); + list_del_init(&d->ld_linkage); spin_unlock(&s->ls_ld_lock); } EXPORT_SYMBOL(lu_dev_del_linkage); /** - * Initialize site \a s, with \a d as the top level device. - */ -#define LU_SITE_BITS_MIN 12 -#define LU_SITE_BITS_MAX 24 -/** - * total 256 buckets, we don't want too many buckets because: - * - consume too much memory - * - avoid unbalanced LRU list - */ -#define LU_SITE_BKT_BITS 8 - + * Initialize site \a s, with \a d as the top level device. + */ int lu_site_init(struct lu_site *s, struct lu_device *top) { - struct lu_site_bkt_data *bkt; - cfs_hash_bd_t bd; - char name[16]; - int bits; - int i; - ENTRY; - - memset(s, 0, sizeof *s); - bits = lu_htable_order(); - snprintf(name, 16, "lu_site_%s", top->ld_type->ldt_name); - for (bits = min(max(LU_SITE_BITS_MIN, bits), LU_SITE_BITS_MAX); - bits >= LU_SITE_BITS_MIN; bits--) { - s->ls_obj_hash = cfs_hash_create(name, bits, bits, - bits - LU_SITE_BKT_BITS, - sizeof(*bkt), 0, 0, - &lu_site_hash_ops, - CFS_HASH_SPIN_BKTLOCK | - CFS_HASH_NO_ITEMREF | - CFS_HASH_DEPTH | - CFS_HASH_ASSERT_EMPTY); - if (s->ls_obj_hash != NULL) - break; - } + struct lu_site_bkt_data *bkt; + struct cfs_hash_bd bd; + char name[16]; + unsigned long bits; + unsigned int i; + int rc; + ENTRY; - if (s->ls_obj_hash == NULL) { - CERROR("failed to create lu_site hash with bits: %d\n", bits); - return -ENOMEM; - } + memset(s, 0, sizeof *s); + mutex_init(&s->ls_purge_mutex); - cfs_hash_for_each_bucket(s->ls_obj_hash, &bd, i) { - bkt = cfs_hash_bd_extra_get(s->ls_obj_hash, &bd); - CFS_INIT_LIST_HEAD(&bkt->lsb_lru); - cfs_waitq_init(&bkt->lsb_marche_funebre); - } +#ifdef HAVE_PERCPU_COUNTER_INIT_GFP_FLAG + rc = percpu_counter_init(&s->ls_lru_len_counter, 0, GFP_NOFS); +#else + rc = percpu_counter_init(&s->ls_lru_len_counter, 0); +#endif + if (rc) + return -ENOMEM; + + snprintf(name, sizeof(name), "lu_site_%s", top->ld_type->ldt_name); + for (bits = lu_htable_order(top); + bits >= LU_SITE_BITS_MIN; bits--) { + s->ls_obj_hash = cfs_hash_create(name, bits, bits, + bits - LU_SITE_BKT_BITS, + sizeof(*bkt), 0, 0, + &lu_site_hash_ops, + CFS_HASH_SPIN_BKTLOCK | + CFS_HASH_NO_ITEMREF | + CFS_HASH_DEPTH | + CFS_HASH_ASSERT_EMPTY | + CFS_HASH_COUNTER); + if (s->ls_obj_hash != NULL) + break; + } + + if (s->ls_obj_hash == NULL) { + CERROR("failed to create lu_site hash with bits: %lu\n", bits); + return -ENOMEM; + } + + cfs_hash_for_each_bucket(s->ls_obj_hash, &bd, i) { + bkt = cfs_hash_bd_extra_get(s->ls_obj_hash, &bd); + INIT_LIST_HEAD(&bkt->lsb_lru); + init_waitqueue_head(&bkt->lsb_marche_funebre); + } s->ls_stats = lprocfs_alloc_stats(LU_SS_LAST_STAT, 0); if (s->ls_stats == NULL) { @@ -1007,13 +1084,13 @@ int lu_site_init(struct lu_site *s, struct lu_device *top) lprocfs_counter_init(s->ls_stats, LU_SS_LRU_PURGED, 0, "lru_purged", "lru_purged"); - CFS_INIT_LIST_HEAD(&s->ls_linkage); + INIT_LIST_HEAD(&s->ls_linkage); s->ls_top_dev = top; top->ld_site = s; lu_device_get(top); lu_ref_add(&top->ld_reference, "site-top", s); - CFS_INIT_LIST_HEAD(&s->ls_ld_linkage); + INIT_LIST_HEAD(&s->ls_ld_linkage); spin_lock_init(&s->ls_ld_lock); lu_dev_add_linkage(s, top); @@ -1027,9 +1104,11 @@ EXPORT_SYMBOL(lu_site_init); */ void lu_site_fini(struct lu_site *s) { - mutex_lock(&lu_sites_guard); - cfs_list_del_init(&s->ls_linkage); - mutex_unlock(&lu_sites_guard); + down_write(&lu_sites_guard); + list_del_init(&s->ls_linkage); + up_write(&lu_sites_guard); + + percpu_counter_destroy(&s->ls_lru_len_counter); if (s->ls_obj_hash != NULL) { cfs_hash_putref(s->ls_obj_hash); @@ -1054,11 +1133,11 @@ EXPORT_SYMBOL(lu_site_fini); int lu_site_init_finish(struct lu_site *s) { int result; - mutex_lock(&lu_sites_guard); + down_write(&lu_sites_guard); result = lu_context_refill(&lu_shrink_env.le_ctx); if (result == 0) - cfs_list_add(&s->ls_linkage, &lu_sites); - mutex_unlock(&lu_sites_guard); + list_add(&s->ls_linkage, &lu_sites); + up_write(&lu_sites_guard); return result; } EXPORT_SYMBOL(lu_site_init_finish); @@ -1068,7 +1147,7 @@ EXPORT_SYMBOL(lu_site_init_finish); */ void lu_device_get(struct lu_device *d) { - cfs_atomic_inc(&d->ld_ref); + atomic_inc(&d->ld_ref); } EXPORT_SYMBOL(lu_device_get); @@ -1077,8 +1156,8 @@ EXPORT_SYMBOL(lu_device_get); */ void lu_device_put(struct lu_device *d) { - LASSERT(cfs_atomic_read(&d->ld_ref) > 0); - cfs_atomic_dec(&d->ld_ref); + LASSERT(atomic_read(&d->ld_ref) > 0); + atomic_dec(&d->ld_ref); } EXPORT_SYMBOL(lu_device_put); @@ -1087,14 +1166,16 @@ EXPORT_SYMBOL(lu_device_put); */ int lu_device_init(struct lu_device *d, struct lu_device_type *t) { - if (t->ldt_device_nr++ == 0 && t->ldt_ops->ldto_start != NULL) - t->ldt_ops->ldto_start(t); - memset(d, 0, sizeof *d); - cfs_atomic_set(&d->ld_ref, 0); - d->ld_type = t; - lu_ref_init(&d->ld_reference); - CFS_INIT_LIST_HEAD(&d->ld_linkage); - return 0; + if (atomic_inc_return(&t->ldt_device_nr) == 1 && + t->ldt_ops->ldto_start != NULL) + t->ldt_ops->ldto_start(t); + + memset(d, 0, sizeof *d); + d->ld_type = t; + lu_ref_init(&d->ld_reference); + INIT_LIST_HEAD(&d->ld_linkage); + + return 0; } EXPORT_SYMBOL(lu_device_init); @@ -1103,20 +1184,21 @@ EXPORT_SYMBOL(lu_device_init); */ void lu_device_fini(struct lu_device *d) { - struct lu_device_type *t; + struct lu_device_type *t = d->ld_type; - t = d->ld_type; - if (d->ld_obd != NULL) { - d->ld_obd->obd_lu_dev = NULL; - d->ld_obd = NULL; - } + if (d->ld_obd != NULL) { + d->ld_obd->obd_lu_dev = NULL; + d->ld_obd = NULL; + } + + lu_ref_fini(&d->ld_reference); + LASSERTF(atomic_read(&d->ld_ref) == 0, + "Refcount is %u\n", atomic_read(&d->ld_ref)); + LASSERT(atomic_read(&t->ldt_device_nr) > 0); - lu_ref_fini(&d->ld_reference); - LASSERTF(cfs_atomic_read(&d->ld_ref) == 0, - "Refcount is %u\n", cfs_atomic_read(&d->ld_ref)); - LASSERT(t->ldt_device_nr > 0); - if (--t->ldt_device_nr == 0 && t->ldt_ops->ldto_stop != NULL) - t->ldt_ops->ldto_stop(t); + if (atomic_dec_and_test(&t->ldt_device_nr) && + t->ldt_ops->ldto_stop != NULL) + t->ldt_ops->ldto_stop(t); } EXPORT_SYMBOL(lu_device_fini); @@ -1124,16 +1206,17 @@ EXPORT_SYMBOL(lu_device_fini); * Initialize object \a o that is part of compound object \a h and was created * by device \a d. */ -int lu_object_init(struct lu_object *o, - struct lu_object_header *h, struct lu_device *d) +int lu_object_init(struct lu_object *o, struct lu_object_header *h, + struct lu_device *d) { - memset(o, 0, sizeof *o); - o->lo_header = h; - o->lo_dev = d; - lu_device_get(d); - o->lo_dev_ref = lu_ref_add(&d->ld_reference, "lu_object", o); - CFS_INIT_LIST_HEAD(&o->lo_linkage); - return 0; + memset(o, 0, sizeof(*o)); + o->lo_header = h; + o->lo_dev = d; + lu_device_get(d); + lu_ref_add_at(&d->ld_reference, &o->lo_dev_ref, "lu_object", o); + INIT_LIST_HEAD(&o->lo_linkage); + + return 0; } EXPORT_SYMBOL(lu_object_init); @@ -1142,16 +1225,16 @@ EXPORT_SYMBOL(lu_object_init); */ void lu_object_fini(struct lu_object *o) { - struct lu_device *dev = o->lo_dev; + struct lu_device *dev = o->lo_dev; - LASSERT(cfs_list_empty(&o->lo_linkage)); + LASSERT(list_empty(&o->lo_linkage)); - if (dev != NULL) { - lu_ref_del_at(&dev->ld_reference, - o->lo_dev_ref , "lu_object", o); - lu_device_put(dev); - o->lo_dev = NULL; - } + if (dev != NULL) { + lu_ref_del_at(&dev->ld_reference, &o->lo_dev_ref, + "lu_object", o); + lu_device_put(dev); + o->lo_dev = NULL; + } } EXPORT_SYMBOL(lu_object_fini); @@ -1163,7 +1246,7 @@ EXPORT_SYMBOL(lu_object_fini); */ void lu_object_add_top(struct lu_object_header *h, struct lu_object *o) { - cfs_list_move(&o->lo_linkage, &h->loh_layers); + list_move(&o->lo_linkage, &h->loh_layers); } EXPORT_SYMBOL(lu_object_add_top); @@ -1175,7 +1258,7 @@ EXPORT_SYMBOL(lu_object_add_top); */ void lu_object_add(struct lu_object *before, struct lu_object *o) { - cfs_list_move(&o->lo_linkage, &before->lo_linkage); + list_move(&o->lo_linkage, &before->lo_linkage); } EXPORT_SYMBOL(lu_object_add); @@ -1185,10 +1268,10 @@ EXPORT_SYMBOL(lu_object_add); int lu_object_header_init(struct lu_object_header *h) { memset(h, 0, sizeof *h); - cfs_atomic_set(&h->loh_ref, 1); - CFS_INIT_HLIST_NODE(&h->loh_hash); - CFS_INIT_LIST_HEAD(&h->loh_lru); - CFS_INIT_LIST_HEAD(&h->loh_layers); + atomic_set(&h->loh_ref, 1); + INIT_HLIST_NODE(&h->loh_hash); + INIT_LIST_HEAD(&h->loh_lru); + INIT_LIST_HEAD(&h->loh_layers); lu_ref_init(&h->loh_reference); return 0; } @@ -1199,9 +1282,9 @@ EXPORT_SYMBOL(lu_object_header_init); */ void lu_object_header_fini(struct lu_object_header *h) { - LASSERT(cfs_list_empty(&h->loh_layers)); - LASSERT(cfs_list_empty(&h->loh_lru)); - LASSERT(cfs_hlist_unhashed(&h->loh_hash)); + LASSERT(list_empty(&h->loh_layers)); + LASSERT(list_empty(&h->loh_lru)); + LASSERT(hlist_unhashed(&h->loh_hash)); lu_ref_fini(&h->loh_reference); } EXPORT_SYMBOL(lu_object_header_fini); @@ -1213,18 +1296,16 @@ EXPORT_SYMBOL(lu_object_header_fini); struct lu_object *lu_object_locate(struct lu_object_header *h, const struct lu_device_type *dtype) { - struct lu_object *o; + struct lu_object *o; - cfs_list_for_each_entry(o, &h->loh_layers, lo_linkage) { - if (o->lo_dev->ld_type == dtype) - return o; - } - return NULL; + list_for_each_entry(o, &h->loh_layers, lo_linkage) { + if (o->lo_dev->ld_type == dtype) + return o; + } + return NULL; } EXPORT_SYMBOL(lu_object_locate); - - /** * Finalize and free devices in the device stack. * @@ -1260,7 +1341,6 @@ void lu_stack_fini(const struct lu_env *env, struct lu_device *top) } } } -EXPORT_SYMBOL(lu_stack_fini); enum { /** @@ -1271,7 +1351,7 @@ enum { static struct lu_context_key *lu_keys[LU_CONTEXT_KEY_NR] = { NULL, }; -static DEFINE_SPINLOCK(lu_keys_guard); +static DECLARE_RWSEM(lu_key_initing); /** * Global counter incremented whenever key is registered, unregistered, @@ -1279,15 +1359,15 @@ static DEFINE_SPINLOCK(lu_keys_guard); * lu_context_refill(). No locking is provided, as initialization and shutdown * are supposed to be externally serialized. */ -static unsigned key_set_version = 0; +static atomic_t key_set_version = ATOMIC_INIT(0); /** * Register new key. */ int lu_context_key_register(struct lu_context_key *key) { - int result; - int i; + int result; + unsigned int i; LASSERT(key->lct_init != NULL); LASSERT(key->lct_fini != NULL); @@ -1295,19 +1375,23 @@ int lu_context_key_register(struct lu_context_key *key) LASSERT(key->lct_owner != NULL); result = -ENFILE; - spin_lock(&lu_keys_guard); + atomic_set(&key->lct_used, 1); + lu_ref_init(&key->lct_reference); for (i = 0; i < ARRAY_SIZE(lu_keys); ++i) { - if (lu_keys[i] == NULL) { - key->lct_index = i; - cfs_atomic_set(&key->lct_used, 1); - lu_keys[i] = key; - lu_ref_init(&key->lct_reference); - result = 0; - ++key_set_version; - break; - } + if (lu_keys[i]) + continue; + key->lct_index = i; + if (cmpxchg(&lu_keys[i], NULL, key) != NULL) + continue; + + result = 0; + atomic_inc(&key_set_version); + break; } - spin_unlock(&lu_keys_guard); + if (result) { + lu_ref_fini(&key->lct_reference); + atomic_set(&key->lct_used, 0); + } return result; } EXPORT_SYMBOL(lu_context_key_register); @@ -1320,16 +1404,17 @@ static void key_fini(struct lu_context *ctx, int index) key = lu_keys[index]; LASSERT(key != NULL); LASSERT(key->lct_fini != NULL); - LASSERT(cfs_atomic_read(&key->lct_used) > 1); + LASSERT(atomic_read(&key->lct_used) > 0); key->lct_fini(ctx, key, ctx->lc_value[index]); lu_ref_del(&key->lct_reference, "ctx", ctx); - cfs_atomic_dec(&key->lct_used); + if (atomic_dec_and_test(&key->lct_used)) + wake_up_var(&key->lct_used); LASSERT(key->lct_owner != NULL); if ((ctx->lc_tags & LCT_NOREF) == 0) { - LINVRNT(cfs_module_refcount(key->lct_owner) > 0); - cfs_module_put(key->lct_owner); + LINVRNT(module_refcount(key->lct_owner) > 0); + module_put(key->lct_owner); } ctx->lc_value[index] = NULL; } @@ -1340,23 +1425,24 @@ static void key_fini(struct lu_context *ctx, int index) */ void lu_context_key_degister(struct lu_context_key *key) { - LASSERT(cfs_atomic_read(&key->lct_used) >= 1); + LASSERT(atomic_read(&key->lct_used) >= 1); LINVRNT(0 <= key->lct_index && key->lct_index < ARRAY_SIZE(lu_keys)); lu_context_key_quiesce(key); - ++key_set_version; - spin_lock(&lu_keys_guard); key_fini(&lu_shrink_env.le_ctx, key->lct_index); - if (lu_keys[key->lct_index]) { - lu_keys[key->lct_index] = NULL; + + /** + * Wait until all transient contexts referencing this key have + * run lu_context_key::lct_fini() method. + */ + atomic_dec(&key->lct_used); + wait_var_event(&key->lct_used, atomic_read(&key->lct_used) == 0); + + if (!WARN_ON(lu_keys[key->lct_index] == NULL)) lu_ref_fini(&key->lct_reference); - } - spin_unlock(&lu_keys_guard); - LASSERTF(cfs_atomic_read(&key->lct_used) == 1, - "key has instances: %d\n", - cfs_atomic_read(&key->lct_used)); + smp_store_release(&lu_keys[key->lct_index], NULL); } EXPORT_SYMBOL(lu_context_key_degister); @@ -1457,7 +1543,8 @@ EXPORT_SYMBOL(lu_context_key_get); /** * List of remembered contexts. XXX document me. */ -static CFS_LIST_HEAD(lu_context_remembered); +static LIST_HEAD(lu_context_remembered); +static DEFINE_SPINLOCK(lu_context_remembered_guard); /** * Destroy \a key in all remembered contexts. This is used to destroy key @@ -1466,38 +1553,37 @@ static CFS_LIST_HEAD(lu_context_remembered); */ void lu_context_key_quiesce(struct lu_context_key *key) { - struct lu_context *ctx; - extern unsigned cl_env_cache_purge(unsigned nr); + struct lu_context *ctx; - if (!(key->lct_tags & LCT_QUIESCENT)) { + if (!(key->lct_tags & LCT_QUIESCENT)) { /* - * XXX layering violation. + * The write-lock on lu_key_initing will ensure that any + * keys_fill() which didn't see LCT_QUIESCENT will have + * finished before we call key_fini(). */ - cl_env_cache_purge(~0); - key->lct_tags |= LCT_QUIESCENT; - /* - * XXX memory barrier has to go here. - */ - spin_lock(&lu_keys_guard); - cfs_list_for_each_entry(ctx, &lu_context_remembered, - lc_remember) + down_write(&lu_key_initing); + key->lct_tags |= LCT_QUIESCENT; + up_write(&lu_key_initing); + + spin_lock(&lu_context_remembered_guard); + list_for_each_entry(ctx, &lu_context_remembered, lc_remember) { + spin_until_cond(READ_ONCE(ctx->lc_state) != LCS_LEAVING); key_fini(ctx, key->lct_index); - spin_unlock(&lu_keys_guard); - ++key_set_version; + } + + spin_unlock(&lu_context_remembered_guard); } } -EXPORT_SYMBOL(lu_context_key_quiesce); void lu_context_key_revive(struct lu_context_key *key) { - key->lct_tags &= ~LCT_QUIESCENT; - ++key_set_version; + key->lct_tags &= ~LCT_QUIESCENT; + atomic_inc(&key_set_version); } -EXPORT_SYMBOL(lu_context_key_revive); static void keys_fini(struct lu_context *ctx) { - int i; + unsigned int i; if (ctx->lc_value == NULL) return; @@ -1511,46 +1597,64 @@ static void keys_fini(struct lu_context *ctx) static int keys_fill(struct lu_context *ctx) { - int i; + unsigned int i; + int rc = 0; - LINVRNT(ctx->lc_value != NULL); - for (i = 0; i < ARRAY_SIZE(lu_keys); ++i) { - struct lu_context_key *key; + /* + * A serialisation with lu_context_key_quiesce() is needed, to + * ensure we see LCT_QUIESCENT and don't allocate a new value + * after it freed one. The rwsem provides this. As down_read() + * does optimistic spinning while the writer is active, this is + * unlikely to ever sleep. + */ + down_read(&lu_key_initing); + ctx->lc_version = atomic_read(&key_set_version); + + LINVRNT(ctx->lc_value); + for (i = 0; i < ARRAY_SIZE(lu_keys); ++i) { + struct lu_context_key *key; + + key = lu_keys[i]; + if (!ctx->lc_value[i] && key && + (key->lct_tags & ctx->lc_tags) && + /* + * Don't create values for a LCT_QUIESCENT key, as this + * will pin module owning a key. + */ + !(key->lct_tags & LCT_QUIESCENT)) { + void *value; + + LINVRNT(key->lct_init != NULL); + LINVRNT(key->lct_index == i); + + LASSERT(key->lct_owner != NULL); + if (!(ctx->lc_tags & LCT_NOREF) && + try_module_get(key->lct_owner) == 0) { + /* module is unloading, skip this key */ + continue; + } + + value = key->lct_init(ctx, key); + if (unlikely(IS_ERR(value))) { + rc = PTR_ERR(value); + break; + } + + lu_ref_add_atomic(&key->lct_reference, "ctx", ctx); + atomic_inc(&key->lct_used); + /* + * This is the only place in the code, where an + * element of ctx->lc_value[] array is set to non-NULL + * value. + */ + ctx->lc_value[i] = value; + if (key->lct_exit != NULL) + ctx->lc_tags |= LCT_HAS_EXIT; + } + } - key = lu_keys[i]; - if (ctx->lc_value[i] == NULL && key != NULL && - (key->lct_tags & ctx->lc_tags) && - /* - * Don't create values for a LCT_QUIESCENT key, as this - * will pin module owning a key. - */ - !(key->lct_tags & LCT_QUIESCENT)) { - void *value; - - LINVRNT(key->lct_init != NULL); - LINVRNT(key->lct_index == i); - - value = key->lct_init(ctx, key); - if (unlikely(IS_ERR(value))) - return PTR_ERR(value); - - LASSERT(key->lct_owner != NULL); - if (!(ctx->lc_tags & LCT_NOREF)) - cfs_try_module_get(key->lct_owner); - lu_ref_add_atomic(&key->lct_reference, "ctx", ctx); - cfs_atomic_inc(&key->lct_used); - /* - * This is the only place in the code, where an - * element of ctx->lc_value[] array is set to non-NULL - * value. - */ - ctx->lc_value[i] = value; - if (key->lct_exit != NULL) - ctx->lc_tags |= LCT_HAS_EXIT; - } - ctx->lc_version = key_set_version; - } - return 0; + up_read(&lu_key_initing); + return rc; } static int keys_init(struct lu_context *ctx) @@ -1573,11 +1677,11 @@ int lu_context_init(struct lu_context *ctx, __u32 tags) ctx->lc_state = LCS_INITIALIZED; ctx->lc_tags = tags; if (tags & LCT_REMEMBER) { - spin_lock(&lu_keys_guard); - cfs_list_add(&ctx->lc_remember, &lu_context_remembered); - spin_unlock(&lu_keys_guard); + spin_lock(&lu_context_remembered_guard); + list_add(&ctx->lc_remember, &lu_context_remembered); + spin_unlock(&lu_context_remembered_guard); } else { - CFS_INIT_LIST_HEAD(&ctx->lc_remember); + INIT_LIST_HEAD(&ctx->lc_remember); } rc = keys_init(ctx); @@ -1597,15 +1701,14 @@ void lu_context_fini(struct lu_context *ctx) ctx->lc_state = LCS_FINALIZED; if ((ctx->lc_tags & LCT_REMEMBER) == 0) { - LASSERT(cfs_list_empty(&ctx->lc_remember)); - keys_fini(ctx); - - } else { /* could race with key degister */ - spin_lock(&lu_keys_guard); - keys_fini(ctx); - cfs_list_del_init(&ctx->lc_remember); - spin_unlock(&lu_keys_guard); + LASSERT(list_empty(&ctx->lc_remember)); + } else { + /* could race with key degister */ + spin_lock(&lu_context_remembered_guard); + list_del_init(&ctx->lc_remember); + spin_unlock(&lu_context_remembered_guard); } + keys_fini(ctx); } EXPORT_SYMBOL(lu_context_fini); @@ -1624,23 +1727,37 @@ EXPORT_SYMBOL(lu_context_enter); */ void lu_context_exit(struct lu_context *ctx) { - int i; + unsigned int i; - LINVRNT(ctx->lc_state == LCS_ENTERED); - ctx->lc_state = LCS_LEFT; - if (ctx->lc_tags & LCT_HAS_EXIT && ctx->lc_value != NULL) { + LINVRNT(ctx->lc_state == LCS_ENTERED); + /* + * Disable preempt to ensure we get a warning if + * any lct_exit ever tries to sleep. That would hurt + * lu_context_key_quiesce() which spins waiting for us. + * This also ensure we aren't preempted while the state + * is LCS_LEAVING, as that too would cause problems for + * lu_context_key_quiesce(). + */ + preempt_disable(); + /* + * Ensure lu_context_key_quiesce() sees LCS_LEAVING + * or we see LCT_QUIESCENT + */ + smp_store_mb(ctx->lc_state, LCS_LEAVING); + if (ctx->lc_tags & LCT_HAS_EXIT && ctx->lc_value) { for (i = 0; i < ARRAY_SIZE(lu_keys); ++i) { - if (ctx->lc_value[i] != NULL) { - struct lu_context_key *key; - - key = lu_keys[i]; - LASSERT(key != NULL); - if (key->lct_exit != NULL) - key->lct_exit(ctx, - key, ctx->lc_value[i]); - } - } + struct lu_context_key *key; + + key = lu_keys[i]; + if (ctx->lc_value[i] && + !(key->lct_tags & LCT_QUIESCENT) && + key->lct_exit) + key->lct_exit(ctx, key, ctx->lc_value[i]); + } } + + smp_store_release(&ctx->lc_state, LCS_LEFT); + preempt_enable(); } EXPORT_SYMBOL(lu_context_exit); @@ -1651,9 +1768,11 @@ EXPORT_SYMBOL(lu_context_exit); */ int lu_context_refill(struct lu_context *ctx) { - return likely(ctx->lc_version == key_set_version) ? 0 : keys_fill(ctx); + if (likely(ctx->lc_version == atomic_read(&key_set_version))) + return 0; + + return keys_fill(ctx); } -EXPORT_SYMBOL(lu_context_refill); /** * lu_ctx_tags/lu_ses_tags will be updated if there are new types of @@ -1662,44 +1781,46 @@ EXPORT_SYMBOL(lu_context_refill); * predefined when the lu_device type are registered, during the module probe * phase. */ -__u32 lu_context_tags_default = 0; -__u32 lu_session_tags_default = 0; +u32 lu_context_tags_default; +u32 lu_session_tags_default; +#ifdef HAVE_SERVER_SUPPORT void lu_context_tags_update(__u32 tags) { - spin_lock(&lu_keys_guard); + spin_lock(&lu_context_remembered_guard); lu_context_tags_default |= tags; - key_set_version++; - spin_unlock(&lu_keys_guard); + atomic_inc(&key_set_version); + spin_unlock(&lu_context_remembered_guard); } EXPORT_SYMBOL(lu_context_tags_update); void lu_context_tags_clear(__u32 tags) { - spin_lock(&lu_keys_guard); + spin_lock(&lu_context_remembered_guard); lu_context_tags_default &= ~tags; - key_set_version++; - spin_unlock(&lu_keys_guard); + atomic_inc(&key_set_version); + spin_unlock(&lu_context_remembered_guard); } EXPORT_SYMBOL(lu_context_tags_clear); void lu_session_tags_update(__u32 tags) { - spin_lock(&lu_keys_guard); + spin_lock(&lu_context_remembered_guard); lu_session_tags_default |= tags; - key_set_version++; - spin_unlock(&lu_keys_guard); + atomic_inc(&key_set_version); + spin_unlock(&lu_context_remembered_guard); } EXPORT_SYMBOL(lu_session_tags_update); void lu_session_tags_clear(__u32 tags) { - spin_lock(&lu_keys_guard); + spin_lock(&lu_context_remembered_guard); lu_session_tags_default &= ~tags; - key_set_version++; - spin_unlock(&lu_keys_guard); + atomic_inc(&key_set_version); + spin_unlock(&lu_context_remembered_guard); } EXPORT_SYMBOL(lu_session_tags_clear); +#endif /* HAVE_SERVER_SUPPORT */ int lu_env_init(struct lu_env *env, __u32 tags) { @@ -1760,7 +1881,102 @@ int lu_env_refill_by_tags(struct lu_env *env, __u32 ctags, } EXPORT_SYMBOL(lu_env_refill_by_tags); -static struct cfs_shrinker *lu_site_shrinker = NULL; + +struct lu_env_item { + struct task_struct *lei_task; /* rhashtable key */ + struct rhash_head lei_linkage; + struct lu_env *lei_env; +}; + +static const struct rhashtable_params lu_env_rhash_params = { + .key_len = sizeof(struct task_struct *), + .key_offset = offsetof(struct lu_env_item, lei_task), + .head_offset = offsetof(struct lu_env_item, lei_linkage), + }; + +struct rhashtable lu_env_rhash; + +struct lu_env_percpu { + struct task_struct *lep_task; + struct lu_env *lep_env ____cacheline_aligned_in_smp; +}; + +static struct lu_env_percpu lu_env_percpu[NR_CPUS]; + +int lu_env_add(struct lu_env *env) +{ + struct lu_env_item *lei, *old; + + LASSERT(env); + + OBD_ALLOC_PTR(lei); + if (!lei) + return -ENOMEM; + + lei->lei_task = current; + lei->lei_env = env; + + old = rhashtable_lookup_get_insert_fast(&lu_env_rhash, + &lei->lei_linkage, + lu_env_rhash_params); + LASSERT(!old); + + return 0; +} +EXPORT_SYMBOL(lu_env_add); + +void lu_env_remove(struct lu_env *env) +{ + struct lu_env_item *lei; + const void *task = current; + int i; + + for_each_possible_cpu(i) { + if (lu_env_percpu[i].lep_env == env) { + LASSERT(lu_env_percpu[i].lep_task == task); + lu_env_percpu[i].lep_task = NULL; + lu_env_percpu[i].lep_env = NULL; + } + } + + rcu_read_lock(); + lei = rhashtable_lookup_fast(&lu_env_rhash, &task, + lu_env_rhash_params); + if (lei && rhashtable_remove_fast(&lu_env_rhash, &lei->lei_linkage, + lu_env_rhash_params) == 0) + OBD_FREE_PTR(lei); + rcu_read_unlock(); +} +EXPORT_SYMBOL(lu_env_remove); + +struct lu_env *lu_env_find(void) +{ + struct lu_env *env = NULL; + struct lu_env_item *lei; + const void *task = current; + int i = get_cpu(); + + if (lu_env_percpu[i].lep_task == current) { + env = lu_env_percpu[i].lep_env; + put_cpu(); + LASSERT(env); + return env; + } + + lei = rhashtable_lookup_fast(&lu_env_rhash, &task, + lu_env_rhash_params); + if (lei) { + env = lei->lei_env; + lu_env_percpu[i].lep_task = current; + lu_env_percpu[i].lep_env = env; + } + put_cpu(); + + return env; +} +EXPORT_SYMBOL(lu_env_find); + +static struct shrinker *lu_site_shrinker; typedef struct lu_site_stats{ unsigned lss_populated; @@ -1769,18 +1985,24 @@ typedef struct lu_site_stats{ unsigned lss_busy; } lu_site_stats_t; -static void lu_site_stats_get(cfs_hash_t *hs, +static void lu_site_stats_get(const struct lu_site *s, lu_site_stats_t *stats, int populated) { - cfs_hash_bd_t bd; - int i; + struct cfs_hash *hs = s->ls_obj_hash; + struct cfs_hash_bd bd; + unsigned int i; + /* + * percpu_counter_sum_positive() won't accept a const pointer + * as it does modify the struct by taking a spinlock + */ + struct lu_site *s2 = (struct lu_site *)s; + stats->lss_busy += cfs_hash_size_get(hs) - + percpu_counter_sum_positive(&s2->ls_lru_len_counter); cfs_hash_for_each_bucket(hs, &bd, i) { - struct lu_site_bkt_data *bkt = cfs_hash_bd_extra_get(hs, &bd); - cfs_hlist_head_t *hhead; + struct hlist_head *hhead; cfs_hash_bd_lock(hs, &bd, 1); - stats->lss_busy += bkt->lsb_busy; stats->lss_total += cfs_hash_bd_count_get(&bd); stats->lss_max_search = max((int)stats->lss_max_search, cfs_hash_bd_depmax_get(&bd)); @@ -1790,16 +2012,91 @@ static void lu_site_stats_get(cfs_hash_t *hs, } cfs_hash_bd_for_each_hlist(hs, &bd, hhead) { - if (!cfs_hlist_empty(hhead)) + if (!hlist_empty(hhead)) stats->lss_populated++; } cfs_hash_bd_unlock(hs, &bd, 1); } } -#ifdef __KERNEL__ /* + * lu_cache_shrink_count() returns an approximate number of cached objects + * that can be freed by shrink_slab(). A counter, which tracks the + * number of items in the site's lru, is maintained in a percpu_counter + * for each site. The percpu values are incremented and decremented as + * objects are added or removed from the lru. The percpu values are summed + * and saved whenever a percpu value exceeds a threshold. Thus the saved, + * summed value at any given time may not accurately reflect the current + * lru length. But this value is sufficiently accurate for the needs of + * a shrinker. + * + * Using a per cpu counter is a compromise solution to concurrent access: + * lu_object_put() can update the counter without locking the site and + * lu_cache_shrink_count can sum the counters without locking each + * ls_obj_hash bucket. + */ +static unsigned long lu_cache_shrink_count(struct shrinker *sk, + struct shrink_control *sc) +{ + struct lu_site *s; + struct lu_site *tmp; + unsigned long cached = 0; + + if (!(sc->gfp_mask & __GFP_FS)) + return 0; + + down_read(&lu_sites_guard); + list_for_each_entry_safe(s, tmp, &lu_sites, ls_linkage) + cached += percpu_counter_read_positive(&s->ls_lru_len_counter); + up_read(&lu_sites_guard); + + cached = (cached / 100) * sysctl_vfs_cache_pressure; + CDEBUG(D_INODE, "%ld objects cached, cache pressure %d\n", + cached, sysctl_vfs_cache_pressure); + + return cached; +} + +static unsigned long lu_cache_shrink_scan(struct shrinker *sk, + struct shrink_control *sc) +{ + struct lu_site *s; + struct lu_site *tmp; + unsigned long remain = sc->nr_to_scan; + LIST_HEAD(splice); + + if (!(sc->gfp_mask & __GFP_FS)) + /* We must not take the lu_sites_guard lock when + * __GFP_FS is *not* set because of the deadlock + * possibility detailed above. Additionally, + * since we cannot determine the number of + * objects in the cache without taking this + * lock, we're in a particularly tough spot. As + * a result, we'll just lie and say our cache is + * empty. This _should_ be ok, as we can't + * reclaim objects when __GFP_FS is *not* set + * anyways. + */ + return SHRINK_STOP; + + down_write(&lu_sites_guard); + list_for_each_entry_safe(s, tmp, &lu_sites, ls_linkage) { + remain = lu_site_purge(&lu_shrink_env, s, remain); + /* + * Move just shrunk site to the tail of site list to + * assure shrinking fairness. + */ + list_move_tail(&s->ls_linkage, &splice); + } + list_splice(&splice, lu_sites.prev); + up_write(&lu_sites_guard); + + return sc->nr_to_scan - remain; +} + +#ifndef HAVE_SHRINKER_COUNT +/* * There exists a potential lock inversion deadlock scenario when using * Lustre on top of ZFS. This occurs between one of ZFS's * buf_hash_table.ht_lock's, and Lustre's lu_sites_guard lock. Essentially, @@ -1814,64 +2111,33 @@ static void lu_site_stats_get(cfs_hash_t *hs, * is safe to take the lu_sites_guard lock. * * Ideally we should accurately return the remaining number of cached - * objects without taking the lu_sites_guard lock, but this is not + * objects without taking the lu_sites_guard lock, but this is not * possible in the current implementation. */ static int lu_cache_shrink(SHRINKER_ARGS(sc, nr_to_scan, gfp_mask)) { - lu_site_stats_t stats; - struct lu_site *s; - struct lu_site *tmp; int cached = 0; - int remain = shrink_param(sc, nr_to_scan); - CFS_LIST_HEAD(splice); - - if (!(shrink_param(sc, gfp_mask) & __GFP_FS)) { - if (remain != 0) - return -1; - else - /* We must not take the lu_sites_guard lock when - * __GFP_FS is *not* set because of the deadlock - * possibility detailed above. Additionally, - * since we cannot determine the number of - * objects in the cache without taking this - * lock, we're in a particularly tough spot. As - * a result, we'll just lie and say our cache is - * empty. This _should_ be ok, as we can't - * reclaim objects when __GFP_FS is *not* set - * anyways. - */ - return 0; - } + struct shrink_control scv = { + .nr_to_scan = shrink_param(sc, nr_to_scan), + .gfp_mask = shrink_param(sc, gfp_mask) + }; +#if !defined(HAVE_SHRINKER_WANT_SHRINK_PTR) && !defined(HAVE_SHRINK_CONTROL) + struct shrinker* shrinker = NULL; +#endif - CDEBUG(D_INODE, "Shrink %d objects\n", remain); - - mutex_lock(&lu_sites_guard); - cfs_list_for_each_entry_safe(s, tmp, &lu_sites, ls_linkage) { - if (shrink_param(sc, nr_to_scan) != 0) { - remain = lu_site_purge(&lu_shrink_env, s, remain); - /* - * Move just shrunk site to the tail of site list to - * assure shrinking fairness. - */ - cfs_list_move_tail(&s->ls_linkage, &splice); - } - memset(&stats, 0, sizeof(stats)); - lu_site_stats_get(s->ls_obj_hash, &stats, 0); - cached += stats.lss_total - stats.lss_busy; - if (shrink_param(sc, nr_to_scan) && remain <= 0) - break; - } - cfs_list_splice(&splice, lu_sites.prev); - mutex_unlock(&lu_sites_guard); + CDEBUG(D_INODE, "Shrink %lu objects\n", scv.nr_to_scan); + + if (scv.nr_to_scan != 0) + lu_cache_shrink_scan(shrinker, &scv); - cached = (cached / 100) * sysctl_vfs_cache_pressure; - if (shrink_param(sc, nr_to_scan) == 0) - CDEBUG(D_INODE, "%d objects cached\n", cached); - return cached; + cached = lu_cache_shrink_count(shrinker, &scv); + return cached; } +#endif /* HAVE_SHRINKER_COUNT */ + + /* * Debugging stuff. */ @@ -1879,13 +2145,13 @@ static int lu_cache_shrink(SHRINKER_ARGS(sc, nr_to_scan, gfp_mask)) /** * Environment to be used in debugger, contains all tags. */ -struct lu_env lu_debugging_env; +static struct lu_env lu_debugging_env; /** * Debugging printer function using printk(). */ int lu_printk_printer(const struct lu_env *env, - void *unused, const char *format, ...) + void *unused, const char *format, ...) { va_list args; @@ -1895,14 +2161,14 @@ int lu_printk_printer(const struct lu_env *env, return 0; } -void lu_debugging_setup(void) +int lu_debugging_setup(void) { - lu_env_init(&lu_debugging_env, ~0); + return lu_env_init(&lu_debugging_env, ~0); } void lu_context_keys_dump(void) { - int i; + unsigned int i; for (i = 0; i < ARRAY_SIZE(lu_keys); ++i) { struct lu_context_key *key; @@ -1912,84 +2178,22 @@ void lu_context_keys_dump(void) CERROR("[%d]: %p %x (%p,%p,%p) %d %d \"%s\"@%p\n", i, key, key->lct_tags, key->lct_init, key->lct_fini, key->lct_exit, - key->lct_index, cfs_atomic_read(&key->lct_used), + key->lct_index, atomic_read(&key->lct_used), key->lct_owner ? key->lct_owner->name : "", key->lct_owner); lu_ref_print(&key->lct_reference); } } } -EXPORT_SYMBOL(lu_context_keys_dump); -#else /* !__KERNEL__ */ -static int lu_cache_shrink(int nr, unsigned int gfp_mask) -{ - return 0; -} -#endif /* __KERNEL__ */ - -int cl_global_init(void); -void cl_global_fini(void); -int lu_ref_global_init(void); -void lu_ref_global_fini(void); - -int dt_global_init(void); -void dt_global_fini(void); - -int llo_global_init(void); -void llo_global_fini(void); - -/* context key constructor/destructor: lu_ucred_key_init, lu_ucred_key_fini */ -LU_KEY_INIT_FINI(lu_ucred, struct lu_ucred); - -static struct lu_context_key lu_ucred_key = { - .lct_tags = LCT_SESSION, - .lct_init = lu_ucred_key_init, - .lct_fini = lu_ucred_key_fini -}; - -/** - * Get ucred key if session exists and ucred key is allocated on it. - * Return NULL otherwise. - */ -struct lu_ucred *lu_ucred(const struct lu_env *env) -{ - if (!env->le_ses) - return NULL; - return lu_context_key_get(env->le_ses, &lu_ucred_key); -} -EXPORT_SYMBOL(lu_ucred); - -/** - * Get ucred key and check if it is properly initialized. - * Return NULL otherwise. - */ -struct lu_ucred *lu_ucred_check(const struct lu_env *env) -{ - struct lu_ucred *uc = lu_ucred(env); - if (uc && uc->uc_valid != UCRED_OLD && uc->uc_valid != UCRED_NEW) - return NULL; - return uc; -} -EXPORT_SYMBOL(lu_ucred_check); - -/** - * Get ucred key, which must exist and must be properly initialized. - * Assert otherwise. - */ -struct lu_ucred *lu_ucred_assert(const struct lu_env *env) -{ - struct lu_ucred *uc = lu_ucred_check(env); - LASSERT(uc != NULL); - return uc; -} -EXPORT_SYMBOL(lu_ucred_assert); /** * Initialization of global lu_* data. */ int lu_global_init(void) { - int result; + int result; + DEF_SHRINKER_VAR(shvar, lu_cache_shrink, + lu_cache_shrink_count, lu_cache_shrink_scan); CDEBUG(D_INFO, "Lustre LU module (%p).\n", &lu_keys); @@ -2002,19 +2206,14 @@ int lu_global_init(void) if (result != 0) return result; - LU_CONTEXT_KEY_INIT(&lu_ucred_key); - result = lu_context_key_register(&lu_ucred_key); - if (result != 0) - return result; - /* * At this level, we don't know what tags are needed, so allocate them * conservatively. This should not be too bad, because this * environment is global. */ - mutex_lock(&lu_sites_guard); + down_write(&lu_sites_guard); result = lu_env_init(&lu_shrink_env, LCT_SHRINKER); - mutex_unlock(&lu_sites_guard); + up_write(&lu_sites_guard); if (result != 0) return result; @@ -2023,25 +2222,11 @@ int lu_global_init(void) * inode, one for ea. Unfortunately setting this high value results in * lu_object/inode cache consuming all the memory. */ - lu_site_shrinker = cfs_set_shrinker(CFS_DEFAULT_SEEKS, lu_cache_shrink); + lu_site_shrinker = set_shrinker(DEFAULT_SEEKS, &shvar); if (lu_site_shrinker == NULL) return -ENOMEM; - result = lu_time_global_init(); - if (result) - GOTO(out, result); - -#ifdef __KERNEL__ - result = dt_global_init(); - if (result) - GOTO(out, result); - - result = llo_global_init(); - if (result) - GOTO(out, result); -#endif - result = cl_global_init(); -out: + result = rhashtable_init(&lu_env_rhash, &lu_env_rhash_params); return result; } @@ -2051,46 +2236,35 @@ out: */ void lu_global_fini(void) { - cl_global_fini(); -#ifdef __KERNEL__ - llo_global_fini(); - dt_global_fini(); -#endif - lu_time_global_fini(); if (lu_site_shrinker != NULL) { - cfs_remove_shrinker(lu_site_shrinker); + remove_shrinker(lu_site_shrinker); lu_site_shrinker = NULL; } - lu_context_key_degister(&lu_global_key); - lu_context_key_degister(&lu_ucred_key); + lu_context_key_degister(&lu_global_key); /* * Tear shrinker environment down _after_ de-registering * lu_global_key, because the latter has a value in the former. */ - mutex_lock(&lu_sites_guard); + down_write(&lu_sites_guard); lu_env_fini(&lu_shrink_env); - mutex_unlock(&lu_sites_guard); + up_write(&lu_sites_guard); + + rhashtable_destroy(&lu_env_rhash); lu_ref_global_fini(); } -struct lu_buf LU_BUF_NULL = { - .lb_buf = NULL, - .lb_len = 0 -}; -EXPORT_SYMBOL(LU_BUF_NULL); - static __u32 ls_stats_read(struct lprocfs_stats *stats, int idx) { -#ifdef LPROCFS - struct lprocfs_counter ret; +#ifdef CONFIG_PROC_FS + struct lprocfs_counter ret; - lprocfs_stats_collect(stats, idx, &ret); - return (__u32)ret.lc_count; + lprocfs_stats_collect(stats, idx, &ret); + return (__u32)ret.lc_count; #else - return 0; + return 0; #endif } @@ -2098,34 +2272,28 @@ static __u32 ls_stats_read(struct lprocfs_stats *stats, int idx) * Output site statistical counters into a buffer. Suitable for * lprocfs_rd_*()-style functions. */ -int lu_site_stats_print(const struct lu_site *s, char *page, int count) +int lu_site_stats_seq_print(const struct lu_site *s, struct seq_file *m) { - lu_site_stats_t stats; + lu_site_stats_t stats; - memset(&stats, 0, sizeof(stats)); - lu_site_stats_get(s->ls_obj_hash, &stats, 1); + memset(&stats, 0, sizeof(stats)); + lu_site_stats_get(s, &stats, 1); - return snprintf(page, count, "%d/%d %d/%d %d %d %d %d %d %d %d\n", - stats.lss_busy, - stats.lss_total, - stats.lss_populated, - CFS_HASH_NHLIST(s->ls_obj_hash), - stats.lss_max_search, - ls_stats_read(s->ls_stats, LU_SS_CREATED), - ls_stats_read(s->ls_stats, LU_SS_CACHE_HIT), - ls_stats_read(s->ls_stats, LU_SS_CACHE_MISS), - ls_stats_read(s->ls_stats, LU_SS_CACHE_RACE), - ls_stats_read(s->ls_stats, LU_SS_CACHE_DEATH_RACE), - ls_stats_read(s->ls_stats, LU_SS_LRU_PURGED)); + seq_printf(m, "%d/%d %d/%d %d %d %d %d %d %d %d\n", + stats.lss_busy, + stats.lss_total, + stats.lss_populated, + CFS_HASH_NHLIST(s->ls_obj_hash), + stats.lss_max_search, + ls_stats_read(s->ls_stats, LU_SS_CREATED), + ls_stats_read(s->ls_stats, LU_SS_CACHE_HIT), + ls_stats_read(s->ls_stats, LU_SS_CACHE_MISS), + ls_stats_read(s->ls_stats, LU_SS_CACHE_RACE), + ls_stats_read(s->ls_stats, LU_SS_CACHE_DEATH_RACE), + ls_stats_read(s->ls_stats, LU_SS_LRU_PURGED)); + return 0; } -EXPORT_SYMBOL(lu_site_stats_print); - -const char *lu_time_names[LU_TIME_NR] = { - [LU_TIME_FIND_LOOKUP] = "find_lookup", - [LU_TIME_FIND_ALLOC] = "find_alloc", - [LU_TIME_FIND_INSERT] = "find_insert" -}; -EXPORT_SYMBOL(lu_time_names); +EXPORT_SYMBOL(lu_site_stats_seq_print); /** * Helper function to initialize a number of kmem slab caches at once. @@ -2136,9 +2304,9 @@ int lu_kmem_init(struct lu_kmem_descr *caches) struct lu_kmem_descr *iter = caches; for (result = 0; iter->ckd_cache != NULL; ++iter) { - *iter->ckd_cache = cfs_mem_cache_create(iter->ckd_name, - iter->ckd_size, - 0, 0); + *iter->ckd_cache = kmem_cache_create(iter->ckd_name, + iter->ckd_size, + 0, 0, NULL); if (*iter->ckd_cache == NULL) { result = -ENOMEM; /* free all previously allocated caches */ @@ -2156,13 +2324,9 @@ EXPORT_SYMBOL(lu_kmem_init); */ void lu_kmem_fini(struct lu_kmem_descr *caches) { - int rc; - for (; caches->ckd_cache != NULL; ++caches) { if (*caches->ckd_cache != NULL) { - rc = cfs_mem_cache_destroy(*caches->ckd_cache); - LASSERTF(rc == 0, "couldn't destroy %s slab\n", - caches->ckd_name); + kmem_cache_destroy(*caches->ckd_cache); *caches->ckd_cache = NULL; } } @@ -2178,24 +2342,26 @@ void lu_object_assign_fid(const struct lu_env *env, struct lu_object *o, { struct lu_site *s = o->lo_dev->ld_site; struct lu_fid *old = &o->lo_header->loh_fid; - struct lu_site_bkt_data *bkt; - struct lu_object *shadow; - cfs_waitlink_t waiter; - cfs_hash_t *hs; - cfs_hash_bd_t bd; - __u64 version = 0; + struct cfs_hash *hs; + struct cfs_hash_bd bd; LASSERT(fid_is_zero(old)); + /* supposed to be unique */ hs = s->ls_obj_hash; cfs_hash_bd_get_and_lock(hs, (void *)fid, &bd, 1); - shadow = htable_lookup(s, &bd, fid, &waiter, &version); - /* supposed to be unique */ - LASSERT(shadow == NULL); +#ifdef CONFIG_LUSTRE_DEBUG_EXPENSIVE_CHECK + { + __u64 version = 0; + struct lu_object *shadow; + + shadow = htable_lookup(s, &bd, fid, &version); + /* supposed to be unique */ + LASSERT(IS_ERR(shadow) && PTR_ERR(shadow) == -ENOENT); + } +#endif *old = *fid; - bkt = cfs_hash_bd_extra_get(hs, &bd); cfs_hash_bd_add_locked(hs, &bd, &o->lo_header->loh_hash); - bkt->lsb_busy++; cfs_hash_bd_unlock(hs, &bd, 1); } EXPORT_SYMBOL(lu_object_assign_fid); @@ -2218,3 +2384,80 @@ struct lu_object *lu_object_anon(const struct lu_env *env, return o; } EXPORT_SYMBOL(lu_object_anon); + +struct lu_buf LU_BUF_NULL = { + .lb_buf = NULL, + .lb_len = 0 +}; +EXPORT_SYMBOL(LU_BUF_NULL); + +void lu_buf_free(struct lu_buf *buf) +{ + LASSERT(buf); + if (buf->lb_buf) { + LASSERT(buf->lb_len > 0); + OBD_FREE_LARGE(buf->lb_buf, buf->lb_len); + buf->lb_buf = NULL; + buf->lb_len = 0; + } +} +EXPORT_SYMBOL(lu_buf_free); + +void lu_buf_alloc(struct lu_buf *buf, size_t size) +{ + LASSERT(buf); + LASSERT(buf->lb_buf == NULL); + LASSERT(buf->lb_len == 0); + OBD_ALLOC_LARGE(buf->lb_buf, size); + if (likely(buf->lb_buf)) + buf->lb_len = size; +} +EXPORT_SYMBOL(lu_buf_alloc); + +void lu_buf_realloc(struct lu_buf *buf, size_t size) +{ + lu_buf_free(buf); + lu_buf_alloc(buf, size); +} +EXPORT_SYMBOL(lu_buf_realloc); + +struct lu_buf *lu_buf_check_and_alloc(struct lu_buf *buf, size_t len) +{ + if (buf->lb_buf == NULL && buf->lb_len == 0) + lu_buf_alloc(buf, len); + + if ((len > buf->lb_len) && (buf->lb_buf != NULL)) + lu_buf_realloc(buf, len); + + return buf; +} +EXPORT_SYMBOL(lu_buf_check_and_alloc); + +/** + * Increase the size of the \a buf. + * preserves old data in buffer + * old buffer remains unchanged on error + * \retval 0 or -ENOMEM + */ +int lu_buf_check_and_grow(struct lu_buf *buf, size_t len) +{ + char *ptr; + + if (len <= buf->lb_len) + return 0; + + OBD_ALLOC_LARGE(ptr, len); + if (ptr == NULL) + return -ENOMEM; + + /* Free the old buf */ + if (buf->lb_buf != NULL) { + memcpy(ptr, buf->lb_buf, buf->lb_len); + OBD_FREE_LARGE(buf->lb_buf, buf->lb_len); + } + + buf->lb_buf = ptr; + buf->lb_len = len; + return 0; +} +EXPORT_SYMBOL(lu_buf_check_and_grow);