From 3a8d4642861fb69b62401949e490c0bcb19ceb40 Mon Sep 17 00:00:00 2001 From: Artem Bityutskiy Date: Sun, 16 Dec 2007 12:32:51 +0200 Subject: [PATCH] UBI: create ltree_entry slab on initialization Since the ltree_entry slab cache is a global entity, which is used by all UBI devices, it is more logical to create it on module initialization time and destro on module exit time. Signed-off-by: Artem Bityutskiy --- drivers/mtd/ubi/build.c | 26 +++++++++++++++ drivers/mtd/ubi/eba.c | 85 +++++++++++-------------------------------------- drivers/mtd/ubi/ubi.h | 23 +++++++++++++ 3 files changed, 67 insertions(+), 67 deletions(-) diff --git a/drivers/mtd/ubi/build.c b/drivers/mtd/ubi/build.c index 5490a73..44c8521 100644 --- a/drivers/mtd/ubi/build.c +++ b/drivers/mtd/ubi/build.c @@ -67,6 +67,9 @@ struct ubi_device *ubi_devices[UBI_MAX_DEVICES]; /* Root UBI "class" object (corresponds to '//class/ubi/') */ struct class *ubi_class; +/* Slab cache for lock-tree entries */ +struct kmem_cache *ubi_ltree_slab; + /* "Show" method for files in '//class/ubi/' */ static ssize_t ubi_version_show(struct class *class, char *buf) { @@ -687,6 +690,20 @@ static void detach_mtd_dev(struct ubi_device *ubi) ubi_msg("mtd%d is detached from ubi%d", mtd_num, ubi_num); } +/** + * ltree_entry_ctor - lock tree entries slab cache constructor. + * @obj: the lock-tree entry to construct + * @cache: the lock tree entry slab cache + * @flags: constructor flags + */ +static void ltree_entry_ctor(struct kmem_cache *cache, void *obj) +{ + struct ubi_ltree_entry *le = obj; + + le->users = 0; + init_rwsem(&le->mutex); +} + static int __init ubi_init(void) { int err, i, k; @@ -709,6 +726,12 @@ static int __init ubi_init(void) if (err) goto out_class; + ubi_ltree_slab = kmem_cache_create("ubi_ltree_slab", + sizeof(struct ubi_ltree_entry), 0, + 0, <ree_entry_ctor); + if (!ubi_ltree_slab) + goto out_version; + /* Attach MTD devices */ for (i = 0; i < mtd_devs; i++) { struct mtd_dev_param *p = &mtd_dev_param[i]; @@ -724,6 +747,8 @@ static int __init ubi_init(void) out_detach: for (k = 0; k < i; k++) detach_mtd_dev(ubi_devices[k]); + kmem_cache_destroy(ubi_ltree_slab); +out_version: class_remove_file(ubi_class, &ubi_version); out_class: class_destroy(ubi_class); @@ -737,6 +762,7 @@ static void __exit ubi_exit(void) for (i = 0; i < n; i++) detach_mtd_dev(ubi_devices[i]); + kmem_cache_destroy(ubi_ltree_slab); class_remove_file(ubi_class, &ubi_version); class_destroy(ubi_class); } diff --git a/drivers/mtd/ubi/eba.c b/drivers/mtd/ubi/eba.c index c87db07..5fdb31b 100644 --- a/drivers/mtd/ubi/eba.c +++ b/drivers/mtd/ubi/eba.c @@ -31,7 +31,7 @@ * logical eraseblock it is locked for reading or writing. The per-logical * eraseblock locking is implemented by means of the lock tree. The lock tree * is an RB-tree which refers all the currently locked logical eraseblocks. The - * lock tree elements are &struct ltree_entry objects. They are indexed by + * lock tree elements are &struct ubi_ltree_entry objects. They are indexed by * (@vol_id, @lnum) pairs. * * EBA also maintains the global sequence counter which is incremented each @@ -50,29 +50,6 @@ #define EBA_RESERVED_PEBS 1 /** - * struct ltree_entry - an entry in the lock tree. - * @rb: links RB-tree nodes - * @vol_id: volume ID of the locked logical eraseblock - * @lnum: locked logical eraseblock number - * @users: how many tasks are using this logical eraseblock or wait for it - * @mutex: read/write mutex to implement read/write access serialization to - * the (@vol_id, @lnum) logical eraseblock - * - * When a logical eraseblock is being locked - corresponding &struct ltree_entry - * object is inserted to the lock tree (@ubi->ltree). - */ -struct ltree_entry { - struct rb_node rb; - int vol_id; - int lnum; - int users; - struct rw_semaphore mutex; -}; - -/* Slab cache for lock-tree entries */ -static struct kmem_cache *ltree_slab; - -/** * next_sqnum - get next sequence number. * @ubi: UBI device description object * @@ -112,20 +89,20 @@ static int ubi_get_compat(const struct ubi_device *ubi, int vol_id) * @vol_id: volume ID * @lnum: logical eraseblock number * - * This function returns a pointer to the corresponding &struct ltree_entry + * This function returns a pointer to the corresponding &struct ubi_ltree_entry * object if the logical eraseblock is locked and %NULL if it is not. * @ubi->ltree_lock has to be locked. */ -static struct ltree_entry *ltree_lookup(struct ubi_device *ubi, int vol_id, - int lnum) +static struct ubi_ltree_entry *ltree_lookup(struct ubi_device *ubi, int vol_id, + int lnum) { struct rb_node *p; p = ubi->ltree.rb_node; while (p) { - struct ltree_entry *le; + struct ubi_ltree_entry *le; - le = rb_entry(p, struct ltree_entry, rb); + le = rb_entry(p, struct ubi_ltree_entry, rb); if (vol_id < le->vol_id) p = p->rb_left; @@ -155,12 +132,12 @@ static struct ltree_entry *ltree_lookup(struct ubi_device *ubi, int vol_id, * Returns pointer to the lock tree entry or %-ENOMEM if memory allocation * failed. */ -static struct ltree_entry *ltree_add_entry(struct ubi_device *ubi, int vol_id, - int lnum) +static struct ubi_ltree_entry *ltree_add_entry(struct ubi_device *ubi, + int vol_id, int lnum) { - struct ltree_entry *le, *le1, *le_free; + struct ubi_ltree_entry *le, *le1, *le_free; - le = kmem_cache_alloc(ltree_slab, GFP_NOFS); + le = kmem_cache_alloc(ubi_ltree_slab, GFP_NOFS); if (!le) return ERR_PTR(-ENOMEM); @@ -189,7 +166,7 @@ static struct ltree_entry *ltree_add_entry(struct ubi_device *ubi, int vol_id, p = &ubi->ltree.rb_node; while (*p) { parent = *p; - le1 = rb_entry(parent, struct ltree_entry, rb); + le1 = rb_entry(parent, struct ubi_ltree_entry, rb); if (vol_id < le1->vol_id) p = &(*p)->rb_left; @@ -211,7 +188,7 @@ static struct ltree_entry *ltree_add_entry(struct ubi_device *ubi, int vol_id, spin_unlock(&ubi->ltree_lock); if (le_free) - kmem_cache_free(ltree_slab, le_free); + kmem_cache_free(ubi_ltree_slab, le_free); return le; } @@ -227,7 +204,7 @@ static struct ltree_entry *ltree_add_entry(struct ubi_device *ubi, int vol_id, */ static int leb_read_lock(struct ubi_device *ubi, int vol_id, int lnum) { - struct ltree_entry *le; + struct ubi_ltree_entry *le; le = ltree_add_entry(ubi, vol_id, lnum); if (IS_ERR(le)) @@ -245,7 +222,7 @@ static int leb_read_lock(struct ubi_device *ubi, int vol_id, int lnum) static void leb_read_unlock(struct ubi_device *ubi, int vol_id, int lnum) { int free = 0; - struct ltree_entry *le; + struct ubi_ltree_entry *le; spin_lock(&ubi->ltree_lock); le = ltree_lookup(ubi, vol_id, lnum); @@ -259,7 +236,7 @@ static void leb_read_unlock(struct ubi_device *ubi, int vol_id, int lnum) up_read(&le->mutex); if (free) - kmem_cache_free(ltree_slab, le); + kmem_cache_free(ubi_ltree_slab, le); } /** @@ -273,7 +250,7 @@ static void leb_read_unlock(struct ubi_device *ubi, int vol_id, int lnum) */ static int leb_write_lock(struct ubi_device *ubi, int vol_id, int lnum) { - struct ltree_entry *le; + struct ubi_ltree_entry *le; le = ltree_add_entry(ubi, vol_id, lnum); if (IS_ERR(le)) @@ -291,7 +268,7 @@ static int leb_write_lock(struct ubi_device *ubi, int vol_id, int lnum) static void leb_write_unlock(struct ubi_device *ubi, int vol_id, int lnum) { int free; - struct ltree_entry *le; + struct ubi_ltree_entry *le; spin_lock(&ubi->ltree_lock); le = ltree_lookup(ubi, vol_id, lnum); @@ -306,7 +283,7 @@ static void leb_write_unlock(struct ubi_device *ubi, int vol_id, int lnum) up_write(&le->mutex); if (free) - kmem_cache_free(ltree_slab, le); + kmem_cache_free(ubi_ltree_slab, le); } /** @@ -931,20 +908,6 @@ write_error: } /** - * ltree_entry_ctor - lock tree entries slab cache constructor. - * @obj: the lock-tree entry to construct - * @cache: the lock tree entry slab cache - * @flags: constructor flags - */ -static void ltree_entry_ctor(struct kmem_cache *cache, void *obj) -{ - struct ltree_entry *le = obj; - - le->users = 0; - init_rwsem(&le->mutex); -} - -/** * ubi_eba_copy_leb - copy logical eraseblock. * @ubi: UBI device description object * @from: physical eraseblock number from where to copy @@ -1128,14 +1091,6 @@ int ubi_eba_init_scan(struct ubi_device *ubi, struct ubi_scan_info *si) mutex_init(&ubi->alc_mutex); ubi->ltree = RB_ROOT; - if (ubi_devices_cnt == 0) { - ltree_slab = kmem_cache_create("ubi_ltree_slab", - sizeof(struct ltree_entry), 0, - 0, <ree_entry_ctor); - if (!ltree_slab) - return -ENOMEM; - } - ubi->global_sqnum = si->max_sqnum + 1; num_volumes = ubi->vtbl_slots + UBI_INT_VOL_COUNT; @@ -1205,8 +1160,6 @@ out_free: continue; kfree(ubi->volumes[i]->eba_tbl); } - if (ubi_devices_cnt == 0) - kmem_cache_destroy(ltree_slab); return err; } @@ -1225,6 +1178,4 @@ void ubi_eba_close(const struct ubi_device *ubi) continue; kfree(ubi->volumes[i]->eba_tbl); } - if (ubi_devices_cnt == 1) - kmem_cache_destroy(ltree_slab); } diff --git a/drivers/mtd/ubi/ubi.h b/drivers/mtd/ubi/ubi.h index 318ce25..0f2ea81 100644 --- a/drivers/mtd/ubi/ubi.h +++ b/drivers/mtd/ubi/ubi.h @@ -97,6 +97,28 @@ enum { extern int ubi_devices_cnt; extern struct ubi_device *ubi_devices[]; +/** + * struct ubi_ltree_entry - an entry in the lock tree. + * @rb: links RB-tree nodes + * @vol_id: volume ID of the locked logical eraseblock + * @lnum: locked logical eraseblock number + * @users: how many tasks are using this logical eraseblock or wait for it + * @mutex: read/write mutex to implement read/write access serialization to + * the (@vol_id, @lnum) logical eraseblock + * + * This data structure is used in the EBA unit to implement per-LEB locking. + * When a logical eraseblock is being locked - corresponding + * &struct ubi_ltree_entry object is inserted to the lock tree (@ubi->ltree). + * See EBA unit for details. + */ +struct ubi_ltree_entry { + struct rb_node rb; + int vol_id; + int lnum; + int users; + struct rw_semaphore mutex; +}; + struct ubi_volume_desc; /** @@ -359,6 +381,7 @@ struct ubi_device { #endif }; +extern struct kmem_cache *ubi_ltree_slab; extern struct file_operations ubi_cdev_operations; extern struct file_operations ubi_vol_cdev_operations; extern struct class *ubi_class; -- 2.7.4